Coal exploitation inevitably damages the natural ecological environment through large scale underground exploitation which exhausts the surrounding areas and is the cause of surface subsidence and cracks. These types ...Coal exploitation inevitably damages the natural ecological environment through large scale underground exploitation which exhausts the surrounding areas and is the cause of surface subsidence and cracks. These types of damage seriously lower the underground water table. Deterioration of the environment has certainly an impact on and limits growth of vegetation,which is a very important indicator of a healthy ecological system. Dynamically monitoring vegetation growth under coal exploitation stress by remote sensing technology provides advantages such as large scale coverage,high accuracy and abundant information. A scatter plot was built by a TM (Thematic Mapper) infrared and red bands. A detailed analysis of the distributional characteristics of vegetation pixels has been carried out. Results show that vegetation pixels are affected by soil background pixels,while the distribution of soil pixels presents a linear pattern. Soil line equations were obtained mainly by linear regression. A new band,reflecting vegetation growth,has been obtained based on the elimination of the soil background. A grading of vegetation images was extracted by means of a density slice method. Our analysis indicates that before the exploitation of the Bulianta coal mining area,vegetation growth had gradually reduced; especially intermediate growth vegetation had been transformed into low vegetation. It may have been caused by the deterioration of the brittle environment in the western part of the mining area. All the same,after the start of coal production,vegetation growth has gradually improved,probably due to large scale aerial seeding. Remote sensing interpretation results proved to be consistent with the actual situation on the ground. From our research results we can not conclude that coal exploitation stress has no impact on the growth of vegetation. More de-tailed research on vegetation growth needs to be analyzed.展开更多
Launched in 2002, the Beiing–Tianjin Sand Source Control Project (BTSSCP) is an ecological restoration project intended to prevent desertification in China. Evidence from multiple sources has confirmed increases in v...Launched in 2002, the Beiing–Tianjin Sand Source Control Project (BTSSCP) is an ecological restoration project intended to prevent desertification in China. Evidence from multiple sources has confirmed increases in vegetation growth in the BTSSCP region since the initiation of this project. Precipitation and essential climate variable-soil moisture (ECV-SM) conditions are typically considered to be the main drivers of vegetation growth in this region. Although many studies have investigated the inter-annual variations of vegetation growth, few concerns have been focused on the annual and seasonal variations of vegetation growth and their climatic drivers, which are crucial for understanding the relationships among the climate, vegetation, and human activities at the regional scale. Based on the normalized difference vegetation index (NDVI) derived from MODIS and the corresponding climatic data, we explored the responses of vegetation growth to climatic factors at annual and seasonal scales in the BTSSCP region during the period 2000–2014. Over the study region as a whole, NDVI generally increased from 2000 to 2014, at a rate of 0.002/a. Vegetation growth is stimulated mainly by the elevated temperature in spring, whereas precipitation is the leading driver of summer greening. In autumn, positive effects of both temperature and precipitation on vegetation growth were observed. The warming in spring promotes vegetation growth but reduces ECV-SM. Summer greening has a strong cooling effect on land surface temperature. These results indicate that the ecological and environmental consequences of ecological restoration projects should be comprehensively evaluated.展开更多
Though many studies have focused on the causes of shifts in trend of temperature, whether the response of vegetation growth to temperature has changed is still not very clear. In this study, we analyzed the spatial fe...Though many studies have focused on the causes of shifts in trend of temperature, whether the response of vegetation growth to temperature has changed is still not very clear. In this study, we analyzed the spatial features of the trend changes of temperature during the growing season and the response of vegetation growth in China based on observed climatic data and the normalized difference vegetation index (NDVI) from 1984 to 2011. An obvious warming to cooling shift during growing season from the period 1984-1997 to the period 1998-2011 was identified in the northern and northeastern regions of China, whereas a totally converse shift was observed in the southern and western regions, suggesting large spatial heterogeneity of changes of the trend of growing season temperature throughout China. China as a whole, a significant positive relationship between vegetation growth and tem- perature during 1984 to 1997 has been greatly weakened during 1998-2011. This change of response of vegetation growth to temperature has also been confirmed by Granger causality test. On regional scales, obvious shifts in relationship between vegetation growth and tem- perature were identified in temperate desert region and rainforest region. Furthermore, by comprehensively analyzing of the relationship between NDVI and climate variables, an over- all reduction of impacts of climate factors on vegetation growth was identified over China during recent years, indicating enhanced influences from human associated activities.展开更多
Climate warming has been projected to enhance vegetation growth more strongly in higher latitudes than in lower latitudes,but different projections show distinct regional differences.By employing big data analysis(dee...Climate warming has been projected to enhance vegetation growth more strongly in higher latitudes than in lower latitudes,but different projections show distinct regional differences.By employing big data analysis(deep learning),we established gridded,global-scale,climate-driven vegetation growth models to project future changes in vegetation growth under SSP scenarios.We projected no substantial trends of vegetation growth change under the sustainable development scenario(SSP1-1.9)by the end of the 21st century.However,the increase of vegetation growth driven by climate warming shows distinct regional variability under the scenario representing high carbon emissions and severe warming(SSP5-8.5),especially in Northeast Asia where growth could increase by(6.00%±4.21%).This may be attributed to the high temperature sensitivities of the deciduous needleleaf forests and permanent wetlands in these regions.When the temperature sensitivity that is defined as permutation importance in deep learning is greater than 0.05,the increase in vegetation growth will be more prominent.In addition,an extreme temperature increase across grasslands,as well as changing land-use management in northern China may also influence the vegetation growth in the future.The results suggest that the sustainable development scenario can maintain stable vegetation growth,and it may be a reliable way to mitigate global warming due to potential climate feedbacks driven by vegetation changes in boreal regions.Deciduous needleleaf forests will be a centre of greening in the future,and it should become the focus of future vegetation dynamics modelling studies and projections.展开更多
The vegetation growth status largely represents the ecosystem function and environmental quality.Hyperspectral remote sensing data can effectively eliminate the effects of surface spectral reflectance and atmospheric ...The vegetation growth status largely represents the ecosystem function and environmental quality.Hyperspectral remote sensing data can effectively eliminate the effects of surface spectral reflectance and atmospheric scattering and directly reflect the vegetation parameter information.In this study,the abandoned mining area in the Helan Mountains,China was taken as the study area.Based on hyperspectral remote sensing images of Zhuhai No.1 hyperspectral satellite,we used the pixel dichotomy model,which was constructed using the normalized difference vegetation index(NDVI),to estimate the vegetation coverage of the study area,and evaluated the vegetation growth status by five vegetation indices(NDVI,ratio vegetation index(RVI),photochemical vegetation index(PVI),red-green ratio index(RGI),and anthocyanin reflectance index 1(ARI1)).According to the results,the reclaimed vegetation growth status in the study area can be divided into four levels(unhealthy,low healthy,healthy,and very healthy).The overall vegetation growth status in the study area was generally at low healthy level,indicating that the vegetation growth status in the study area was not good due to short-time period restoration and harsh damaged environment such as high and steep rock slopes.Furthermore,the unhealthy areas were mainly located in Dawukougou where abandoned mines were concentrated,indicating that the original mining activities have had a large effect on vegetation ecology.After ecological restoration of abandoned mines,the vegetation coverage in the study area has increased to a certain extent,but the amplitude was not large.The situation of vegetation coverage in the northern part of the study area was worse than that in the southern part,due to abandoned mines mainly concentrating in the northern part of the Helan Mountains.The combination of hyperspectral remote sensing data and vegetation indices can comprehensively extract the characteristics of vegetation,accurately analyze the plant growth status,and provide technical support for vegetation health evaluation.展开更多
Leaves are the main organ for photosynthesis and organic synthesis in cotton.Leaf shape has important effects on photosynthetic efficiency and canopy formation,thereby affecting cotton yield.Previous studies have show...Leaves are the main organ for photosynthesis and organic synthesis in cotton.Leaf shape has important effects on photosynthetic efficiency and canopy formation,thereby affecting cotton yield.Previous studies have shown that LMI1(LATE MERISTEM IDENTITY1)is the main gene regulating leaf shape.In this study,the LMI1 gene was inserted into the 35S promoter expression vector,and cotton plants overexpressing LMI1(OE)were obtained through genetic transformation.Statistical analysis of the biological traits of the T_(1) and T_(2) populations showed that compared to the wild type(WT),OE plants had significantly larger leaves,thicker stems and significantly greater dry weight.Furthermore,plant sections of the main vein and petiole showed that the numbers of cells in those tissues of OE plants were significantly greater.In addition,RNA-seq analysis revealed the differential expression of genes related to gibberellin synthesis and NAC gene family(genes containing the NAC domain)between the OE and WT plants,suggesting that LMI1 is involved in secondary wall formation and cell proliferation,which promotes stem thickening.Moreover,Gene Ontology(GO)analysis revealed enrichment in the terms of calcium ion binding,and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis showed enrichment in the terms of fatty acid degradation,phosphatidylinositol signal transduction system,and c AMP(cyclic adenosine monophosphate)signal pathway.These results suggested that LMI1 OE plants are responsive to gibberellin hormone signals,and have altered messenger signals(c AMP,Ca^(2+))which amplify this function,to promote stronger aboveground vegetative growth.This study found the LMI1 greatly increased the vegetative growth in cotton,which is the basic requirement for higher yield.展开更多
ObjectiveThis study aimed to investigate the effect of the interactions among potassium (K), calcium (Ca) and sodium (Na) on cabbage growth and nutrient absorption. MethodA total of 11 treatments with different ...ObjectiveThis study aimed to investigate the effect of the interactions among potassium (K), calcium (Ca) and sodium (Na) on cabbage growth and nutrient absorption. MethodA total of 11 treatments with different levels of K, Ca and Na were set in the pot experiment to measure the nutrient content and uptake in cabbage plants. ResultThe use of K or the combined use of K and Ca improved the cabbage absorption on K and Ca. In addition, K and Ca presented an interaction as that appropriate amount of Ca promoted K uptake while excessive Ca inhibited the uptake. The treatment of Ca 2 K 3 with 0.33 g/pot of Ca and 0.67 g/pot of K could significantly increase the quantity of dry matter accumulation and absorption of Ca and K in cabbage, was the best among all treatments. ConclusionApplication of suitable amount of Ca could release the Na stress on cabbage growth at the low level of Na in soil.展开更多
Climate change and human activity have resulted in increasing change of vegetation growth globally. Numerous studies have been conducted on extreme climate events and analyses of ecological environment evolution. Howe...Climate change and human activity have resulted in increasing change of vegetation growth globally. Numerous studies have been conducted on extreme climate events and analyses of ecological environment evolution. However, such studies have placed little emphasis on vegetation change and spatial variation in this type of ecotone. Accordingly, this study analyzed the changes in vegetation type and growth using the 16-d composite MOD13A1 product with 1-km resolution and MOD12Q1 product with 1-km resolution. We used the mean, maximum, standard deviation normalized-difference vegetation index(NDVI) values, and the rate of change(ROC) of NDVI value to explain vegetation changes within the studied ecotone. Our results showed that significant vegetation type and growth changes have occurred in the study area. From 2001 to 2013, for example, with the exception of 2001, 2004 and 2009, a certain extent of grassland area was converted to cropland. Drought severity index(DSI) results indicate that there exists drought in 2001, 2004 and 2009. Such temporal changes in cropland and grassland area confirmed the ecological vulnerability of the ecotone. At the same time, vegetation varied spatially from west to east and from south to north. The mean, maximum and standard deviation NDVI values were all sorted in descending order based on differences in latitude and longitude, as follows: NDVI_(2013)〉NDVI_(2009)〉NDVI_(2004)〉NDVI_(2001)展开更多
Tiffs paper reports the effects of moso bamboo (Phyllostachys pubescense) vinegar, with different diluents, on the growth of lettuce, cole and cucumber based on field tests. The results show that moso bamboo vinegar...Tiffs paper reports the effects of moso bamboo (Phyllostachys pubescense) vinegar, with different diluents, on the growth of lettuce, cole and cucumber based on field tests. The results show that moso bamboo vinegar with 500-800 times dilution had good effect on the growth of tested vegetables. The harvest of vegetables increased from 18.8%-20.2% compared with a control. The height and the weight of the average single vegetable tested also increased. The main components of moso bamboo vinegar were analyzed by GC-MS and the positive effect on the growth was, in the first instance, attributed to a synergistic effect of trace amounts of the main components of bamboo vinegar.展开更多
Vegetative growth of young apple trees trained in vertical axis were studied with ' Red Fuji', 'Jonagold', 'Orin' and ' Starkrimson' on M7, MM106, M26 interstocks in northern China. Abo...Vegetative growth of young apple trees trained in vertical axis were studied with ' Red Fuji', 'Jonagold', 'Orin' and ' Starkrimson' on M7, MM106, M26 interstocks in northern China. About 30 branches sprouted from the central leader of the trees during the 4 years after planting for ' Red Fuji' and 'Jonagold', and 26.7 and 20 branches respectively for 'Orin' and 'Starkrimson'. Moreover the 2-year-old section of the central leader had the strongest capacity to sprout new branches (and sometimes the 1-year-old section too), and sprouted more new shoots than the other section. The total new shoots including spurs on the 4-year-old trees reached 631 per tree for 'Jonagold', about 480 for 'Red Fuji' and 'Orin', and 312 for 'Starkrimson'. Percentage of spurs was about 61% for 'Red Fuji', 73% for 'Jonagold' and 'Orin', and 81% for 'Starkrimson'. Growth vigor of the central leader and limbs of the young apple trees could quickly decline: the growth of the central leader decreased markedly in the fourth year after planting, and branches from the central leader grew vigorously only in the current growth season or in the first two years after branching.展开更多
The leafing rates of fourteen rice varieties were measured in a sowing-time experiment, and a rapid leafing genotype at the vegetative growth stage was discovered in an indica variety Yanhui 559. The leaf number on th...The leafing rates of fourteen rice varieties were measured in a sowing-time experiment, and a rapid leafing genotype at the vegetative growth stage was discovered in an indica variety Yanhui 559. The leaf number on the main culm of Yanhui 559 was always 4-5 leaves more than that of Lemont, and the leafing rate of Yanhui 559 was significantly higher than that of Lemont based on similar growth durations from sowing to heading. Furthermore, the difference of the leafing rate was significant at the vegetative growth stage, but not distinctive at the panicle initiation stage. Genetic analysis of the leafing rates in the two backcross populations of Yanhui 559 and Lemont showed that major and quantitative genes controlled the expression of rapid leafing character. Based on results of investigation for some plants with similar growth durations in the backcrossing populations, the rapid leafing genotypes exhibited earlier tillering and more tiller numbers per plant, and its yield components including the number of panicles per plant and number of grains per panicle were superior to those of the slow leafing genotypes. Further research and application feasibility of the rapid leafing genotype in breeding were discussed.展开更多
[Objectives]This study was conducted to investigate the physiological mechanism of the response of Dahlia pinnata to exogenous uniconazole during vegetative growth.[Methods]The effects of different concentrations(20,3...[Objectives]This study was conducted to investigate the physiological mechanism of the response of Dahlia pinnata to exogenous uniconazole during vegetative growth.[Methods]The effects of different concentrations(20,30,60 and 80 mg/L)of foliar fertilization on stem and leaf growth,chlorophyll and endogenous hormone contents were investigated using dahlia seedlings(cultivar‘Shiwucaiqiu’)cultivated in the open field.[Results]Different concentrations of uniconazole could make dahlia plants dwarf,shorten internodes,increase stem diameter,and deepen leaf color,and the higher the application concentration,the more significant the effects.Compared with the control group,the relative contents of chlorophyll(SPAD value)in various treatment groups increased,the contents of endogenous GA_(3) and IAA decreased,and the contents of ABA increased.Among them,the contents of IAA and ABA also showed a trend of increasing first and then decreasing.[Conclusions]The results indicated that uniconazole could affect the growth of stems and leaves and plant type by regulating photosynthetic pigments and the levels of endogenous hormones in dahlia,and good dwarfing effect and ornamental value could be obtained under the condition of foliar application concentration of 30 mg/L.This study provides a new experimental basis for the cultivation and application of dahlia.展开更多
Two field trials were clone to evaluate the effects of plant density on the growth, development and yield of safflower. The results showed that plant density and season of growth had significant (P ≤ 0.01) effects ...Two field trials were clone to evaluate the effects of plant density on the growth, development and yield of safflower. The results showed that plant density and season of growth had significant (P ≤ 0.01) effects on growth, development, yield components, yield and oil content of safflower. Increasing safflower plant density from 100,000 to 250,000 plants ha^- significantly reduced plant height (13.2%-21.3%), branch number plant^-1 (37%-54.7%), leaf number plant^-1 (39%-39.2%), leaf area (19.5%-53%), plant spread (39.6%-54.4%), root length (28.1%-54.4%), plant biomass (17%-50%), capitula size (12%-12.7%), capitula number plant^-1 (39.5%-50.5%), seed number capitula~ (39%-45%), capitula weight (3.3%-3.6%), seed yield (67.9%-69.8%) and seed oil content (14.7%-20.8%). The reduction in vegetative growth, yield components, yield and oil content of safflower due to increased plant density was attributed to inter and intra-plant competition for light, nutrients and water necessary for growth and development. The differences between winter and summer grown safflower were attributed to difference in day and night temperature (DIF) and the average daily temperature which were optimum for safflower growth in winter. It was concluded that under Botswana conditions or in semi-arid areas, safflower should be planted at 50 cm × 20 cm or wider in order to maximize yield and oil content and allow the plants to express their maximum genetic potential.展开更多
Centella asiatica (L.) is commonly known as Thankuni plant and has ethnobotanical importance in Bangladesh. Present experiment was conceded to investigate the wilt disease of C. asiatica, vegetative growth and molecul...Centella asiatica (L.) is commonly known as Thankuni plant and has ethnobotanical importance in Bangladesh. Present experiment was conceded to investigate the wilt disease of C. asiatica, vegetative growth and molecular characterization of pathogenic fungi. Pathogenic fungus, Fusarium equiseti was identified as a causal agent of wilt disease in C. asiatica. The effect of culture media on the mycelial growth of F. equiseti showed the highest (89.25 mm) on potato dextrose agar (PDA) medium followed by carrot agar (CA) medium and the lowest growth (40.25 mm) was measured in HA medium. The optimal temperature and pH for mycelial growth of F. equiseti were 30°C and 7, respectively. The genetic variation of the selected species of fungi, the internal transcribed spacer (ITS) region was amplified using ITS4 and ITS5 primers and sequenced. The PCR product of the ITS region of F. equiseti was 535 bp. Phylogenetic tree of thirty-seven strains of Fusarium sp. based on the nucleotide sequences of the ITS region using the neighbor-joining method with 1000 bootstrapping indicated that 98% - 100% identity with MN886590.1 JUF0046 (F. equiseti). ITS sequences are generally constant, or show little variation within species, but vary between species in a genus. The ITS region is relatively short and can be easily amplified by PCR using universal single primer pairs. Genetic distance exhibited high level of similarity with identical ITS sequences. To date, no published research articles are found on the molecular identification of F. equiseti, the causal agent of fusarium wilt disease of C. asiatica in Bangladesh.展开更多
The response of grain yield, biomass yield and harvest index of maize to the application of commercial organic ameliorants was inconsistent and poor. Hence it was hypothesized that the supply of N and P to maize plant...The response of grain yield, biomass yield and harvest index of maize to the application of commercial organic ameliorants was inconsistent and poor. Hence it was hypothesized that the supply of N and P to maize plants was inadequate during vegetative growth, resulting in low concentrations of the two nutrients in maize biomass. The effects of nine ameliorants on the N and P concentrations of maize plants at ninth leaf (V9) and silking (R1) stages of maize were studied over three years at Bothaville (8% clay), Ottosdal (12% clay) and Potchefstroom (34% clay). All ameliorants were applied as prescribed by manufacturers. The N and P concentrations in maize biomass of the ameliorants at V9 and R1 were lower, comparable or higher, showing that the inconsistent and poor response of yield parameters can not be ascribed to inadequate uptake of N and P. A matter of concern that justifies thorough investigation, is the prescribed use of Crop care and Growmor with partial and of Montys and Promis with no NPK fertilization, an unsustainable practice over the long term. Characterization of the active ingredient(s) of the ameliorants is deemed also of importance for better insight.展开更多
In order to find out a new way for environment-friendly and resourcelized utilization of cassava starch processing wastewater, the cassava starch anaerobic fermentation liquid was applied in watermelon production, and...In order to find out a new way for environment-friendly and resourcelized utilization of cassava starch processing wastewater, the cassava starch anaerobic fermentation liquid was applied in watermelon production, and its effects on the growth and development, yield and fruit quality of watermelon were investigated. The results showed that the cassava starch anaerobic fermentation liquid significant- ly promoted the vegetative and reproductive growth and improved the yield and fruit quality of watermelon. Compared with conventional fertilization, the application of cassava starch anaerobic fermentation both with COD concentration of 1 200 mg/L according to the amount of 150 t/hm2 promoted the growth of vines and leaves of watermelon plants, brought forward the flowering, fruiting and harvest of watermelon and significantly increased the fruit number, fruit weight, yield, fruit size, fruit shape index, soluble solid content, soluble sugar content, soluble protein content and Vita- min C content of watermelon. At the same time of improving the yield and quality of watermelon, cassava starch anaerobic fermentation liquid was turned into treasure as a liquid fertilizer. This study provides a new ideal for the yield and quality im- provement of watermelon and the wastewater treating of starch factories.展开更多
According to scientific evidence in general, the disappearance of the Tatras tarns as a result of external geomorphological processes has been accepted since the long term analyses of lake sediments and peat bogs, geo...According to scientific evidence in general, the disappearance of the Tatras tarns as a result of external geomorphological processes has been accepted since the long term analyses of lake sediments and peat bogs, geomorphological mapping, geophysical measurements(– all indirect methods). It is paradoxical that the direct cartographic evidence of such changes has not existed until now. In this paper, we evaluate shore line changes of the small mountain glacial lake in the High Tatras-Litworowy Staw lake using a multitemporal analysis of a series of historical orthophotomaps and a historical map. Over the last 100 years, the tarn has lost 46.4% of open water level area. Significant visual changes were caused by vegetation growth of Carex species(sedges) on the water's surface. The accumulation of fine sediments and dead plant residues in the tarn basin create suitable conditions for this process, all together causing the tarn to become more shallow.展开更多
Straw strip mulching(SM)is a new mulching technology.From 2012 to 2018,SM’s effects on soil moisture and temperature and production performances were compared with other mulching practices,using three treatments:full...Straw strip mulching(SM)is a new mulching technology.From 2012 to 2018,SM’s effects on soil moisture and temperature and production performances were compared with other mulching practices,using three treatments:full-cover plastic mulch(PM),no mulch with wheat sown in rows as the control(CK),and SM with 50%to 59%of the field area mulched.Compared with CK,on average over six growing seasons,SM and PM increased grain yield by 27.0%and 21.7%,straw yield by 21.6%and 22.6%,kernels ha;by 26.6%and 19.0%,net income by 29.8%and-25.0%,soil temperature at 5 cm by-1.5°C and 0.2°C from overwintering to maturity,and soil water storage at 0–200 cm by 25 and 22 mm,respectively.The increase in soil moisture in SM and PM was greater in the early period(overwintering to jointing)than in the later period(booting to maturity)and at 0 to 120 cm than at 120–200 cm in the early period.Although the mean evapotranspiration of whole growth period across six seasons was similar among treatments,SM and PM increased water consumption during the key formation period of yield components after overwintering by 16 and 32 mm,respectively,while reducing it before overwintering.Compared with CK,SM and PM had the effects of warming during overwintering and cooling after jointing.By increasing water consumption after overwintering and ratio of transpiration to evapotranspiration and providing favorable soil temperature for multiple growth stages and more sufficient soil moisture,SM and PM promoted vegetative growth and increased kernels ha^(-1),the main mechanisms by which SM and PM increased grain yield relative to CK.Relative to PM,SM is a more economically beneficial and environment-friendly technology for dryland wheat production.展开更多
There are documentary records referring to paclobutrazol(PBZ)as a growth bioregulator that inhibits the gibberellin synthesis and its application increases yields in fruit and vegetable crop productions.Its agronomic ...There are documentary records referring to paclobutrazol(PBZ)as a growth bioregulator that inhibits the gibberellin synthesis and its application increases yields in fruit and vegetable crop productions.Its agronomic management includes it as an emerging technology to reduce vigour,promote flower induction and flower development in fruit trees with increased economic returns.Its use is banned in some countries because of concerns about residues that can cause harmful effects on the environment.Therefore,the aim of this article was to collect,analyse and summarise relevant information on the use of PBZ in fruit tree production and its possible risks to the environment.The results obtained indicated that the application of PBZ can be effective in solving some problems related to flowering if it is applied in the right amount and at the right time.However,it is necessary to elucidate the physiological processes with which it is associated and its response to be taken into account to increase yield.PBZ is currently used in fruit trees such as mango,lime,apple and guava,increasing their productivity.However,some studies have shown its residual effect on the environment.Therefore,PBZ is a viable strategy,because it presents a series of advantages in the production of fruit trees.However,it is vital to generate protocols that seek its regulation with a rational and sustainable approach.展开更多
Heading date of 26 native japonica rice cultivars in southwest China was investigated,and their basic vegetative growth(BVG),photoperiod-sensitivity(PS) and temperature-sensitivity(TS) were analyzed under artificial s...Heading date of 26 native japonica rice cultivars in southwest China was investigated,and their basic vegetative growth(BVG),photoperiod-sensitivity(PS) and temperature-sensitivity(TS) were analyzed under artificial short-day and natural long-day conditions in Nanjing,as well as artificial high-temperature and natural low-temperature conditions in winter in Hainan.The results showed that the PS and TS varied among different cultivars.The BVG of all the japonica cultivars was well situated,but differed within cultivars.Regression analysis showed a significant correlation between heading date and PS,indicating that PS was the main factor affecting heading date of japonica cultivars in southwest China.Genetic analysis was conducted on these 26 cultivars using a set of heading date near isogenic lines as test lines.All the japonica cultivars carried the dominant early-heading gene Ef-1 or Ef-1t,and most of these cultivars carried the dominant photoperiod sensitivity allele E1 or E1t,the PS of which was slightly weaker than E1.For the Se-1 locus,these cultivars mainly carried recessive photoperiod insensitivity gene Se-1e.In addition,the PS of 22 japonica cultivars could be repressed or weakened by the recessive allele hd2,inhibiting the expression of E1 and Se-1.These results indicated that the genotypes of heading date determined different PS and well situated BVG in japonica rice cultivars in southwest China.展开更多
基金Project 2003AA322040 supported by the National High Technology Research and Development Program of China
文摘Coal exploitation inevitably damages the natural ecological environment through large scale underground exploitation which exhausts the surrounding areas and is the cause of surface subsidence and cracks. These types of damage seriously lower the underground water table. Deterioration of the environment has certainly an impact on and limits growth of vegetation,which is a very important indicator of a healthy ecological system. Dynamically monitoring vegetation growth under coal exploitation stress by remote sensing technology provides advantages such as large scale coverage,high accuracy and abundant information. A scatter plot was built by a TM (Thematic Mapper) infrared and red bands. A detailed analysis of the distributional characteristics of vegetation pixels has been carried out. Results show that vegetation pixels are affected by soil background pixels,while the distribution of soil pixels presents a linear pattern. Soil line equations were obtained mainly by linear regression. A new band,reflecting vegetation growth,has been obtained based on the elimination of the soil background. A grading of vegetation images was extracted by means of a density slice method. Our analysis indicates that before the exploitation of the Bulianta coal mining area,vegetation growth had gradually reduced; especially intermediate growth vegetation had been transformed into low vegetation. It may have been caused by the deterioration of the brittle environment in the western part of the mining area. All the same,after the start of coal production,vegetation growth has gradually improved,probably due to large scale aerial seeding. Remote sensing interpretation results proved to be consistent with the actual situation on the ground. From our research results we can not conclude that coal exploitation stress has no impact on the growth of vegetation. More de-tailed research on vegetation growth needs to be analyzed.
基金financially supported by the National Natural Science Foundation of China (31560135, 41361100)the Discipline Construction Fund Project of Gansu Agricultural University (GAU-XKJS-2018-104, GAU-XKJS-2018-108)the Gansu Science and Technology Support Program (1604FKCA088)
文摘Launched in 2002, the Beiing–Tianjin Sand Source Control Project (BTSSCP) is an ecological restoration project intended to prevent desertification in China. Evidence from multiple sources has confirmed increases in vegetation growth in the BTSSCP region since the initiation of this project. Precipitation and essential climate variable-soil moisture (ECV-SM) conditions are typically considered to be the main drivers of vegetation growth in this region. Although many studies have investigated the inter-annual variations of vegetation growth, few concerns have been focused on the annual and seasonal variations of vegetation growth and their climatic drivers, which are crucial for understanding the relationships among the climate, vegetation, and human activities at the regional scale. Based on the normalized difference vegetation index (NDVI) derived from MODIS and the corresponding climatic data, we explored the responses of vegetation growth to climatic factors at annual and seasonal scales in the BTSSCP region during the period 2000–2014. Over the study region as a whole, NDVI generally increased from 2000 to 2014, at a rate of 0.002/a. Vegetation growth is stimulated mainly by the elevated temperature in spring, whereas precipitation is the leading driver of summer greening. In autumn, positive effects of both temperature and precipitation on vegetation growth were observed. The warming in spring promotes vegetation growth but reduces ECV-SM. Summer greening has a strong cooling effect on land surface temperature. These results indicate that the ecological and environmental consequences of ecological restoration projects should be comprehensively evaluated.
基金Foundation: National Natural Science Foundation of China, No.41671083, No.41301076
文摘Though many studies have focused on the causes of shifts in trend of temperature, whether the response of vegetation growth to temperature has changed is still not very clear. In this study, we analyzed the spatial features of the trend changes of temperature during the growing season and the response of vegetation growth in China based on observed climatic data and the normalized difference vegetation index (NDVI) from 1984 to 2011. An obvious warming to cooling shift during growing season from the period 1984-1997 to the period 1998-2011 was identified in the northern and northeastern regions of China, whereas a totally converse shift was observed in the southern and western regions, suggesting large spatial heterogeneity of changes of the trend of growing season temperature throughout China. China as a whole, a significant positive relationship between vegetation growth and tem- perature during 1984 to 1997 has been greatly weakened during 1998-2011. This change of response of vegetation growth to temperature has also been confirmed by Granger causality test. On regional scales, obvious shifts in relationship between vegetation growth and tem- perature were identified in temperate desert region and rainforest region. Furthermore, by comprehensively analyzing of the relationship between NDVI and climate variables, an over- all reduction of impacts of climate factors on vegetation growth was identified over China during recent years, indicating enhanced influences from human associated activities.
基金supported by the National Natural Science Foundation of China(41790422,42161144008)。
文摘Climate warming has been projected to enhance vegetation growth more strongly in higher latitudes than in lower latitudes,but different projections show distinct regional differences.By employing big data analysis(deep learning),we established gridded,global-scale,climate-driven vegetation growth models to project future changes in vegetation growth under SSP scenarios.We projected no substantial trends of vegetation growth change under the sustainable development scenario(SSP1-1.9)by the end of the 21st century.However,the increase of vegetation growth driven by climate warming shows distinct regional variability under the scenario representing high carbon emissions and severe warming(SSP5-8.5),especially in Northeast Asia where growth could increase by(6.00%±4.21%).This may be attributed to the high temperature sensitivities of the deciduous needleleaf forests and permanent wetlands in these regions.When the temperature sensitivity that is defined as permutation importance in deep learning is greater than 0.05,the increase in vegetation growth will be more prominent.In addition,an extreme temperature increase across grasslands,as well as changing land-use management in northern China may also influence the vegetation growth in the future.The results suggest that the sustainable development scenario can maintain stable vegetation growth,and it may be a reliable way to mitigate global warming due to potential climate feedbacks driven by vegetation changes in boreal regions.Deciduous needleleaf forests will be a centre of greening in the future,and it should become the focus of future vegetation dynamics modelling studies and projections.
基金This research was supported by the Ningxia Hui Autonomous Region Key Research and Development Plan(2022BEG03052).
文摘The vegetation growth status largely represents the ecosystem function and environmental quality.Hyperspectral remote sensing data can effectively eliminate the effects of surface spectral reflectance and atmospheric scattering and directly reflect the vegetation parameter information.In this study,the abandoned mining area in the Helan Mountains,China was taken as the study area.Based on hyperspectral remote sensing images of Zhuhai No.1 hyperspectral satellite,we used the pixel dichotomy model,which was constructed using the normalized difference vegetation index(NDVI),to estimate the vegetation coverage of the study area,and evaluated the vegetation growth status by five vegetation indices(NDVI,ratio vegetation index(RVI),photochemical vegetation index(PVI),red-green ratio index(RGI),and anthocyanin reflectance index 1(ARI1)).According to the results,the reclaimed vegetation growth status in the study area can be divided into four levels(unhealthy,low healthy,healthy,and very healthy).The overall vegetation growth status in the study area was generally at low healthy level,indicating that the vegetation growth status in the study area was not good due to short-time period restoration and harsh damaged environment such as high and steep rock slopes.Furthermore,the unhealthy areas were mainly located in Dawukougou where abandoned mines were concentrated,indicating that the original mining activities have had a large effect on vegetation ecology.After ecological restoration of abandoned mines,the vegetation coverage in the study area has increased to a certain extent,but the amplitude was not large.The situation of vegetation coverage in the northern part of the study area was worse than that in the southern part,due to abandoned mines mainly concentrating in the northern part of the Helan Mountains.The combination of hyperspectral remote sensing data and vegetation indices can comprehensively extract the characteristics of vegetation,accurately analyze the plant growth status,and provide technical support for vegetation health evaluation.
基金supported by the National Natural Science Foundation of China(5201101621)。
文摘Leaves are the main organ for photosynthesis and organic synthesis in cotton.Leaf shape has important effects on photosynthetic efficiency and canopy formation,thereby affecting cotton yield.Previous studies have shown that LMI1(LATE MERISTEM IDENTITY1)is the main gene regulating leaf shape.In this study,the LMI1 gene was inserted into the 35S promoter expression vector,and cotton plants overexpressing LMI1(OE)were obtained through genetic transformation.Statistical analysis of the biological traits of the T_(1) and T_(2) populations showed that compared to the wild type(WT),OE plants had significantly larger leaves,thicker stems and significantly greater dry weight.Furthermore,plant sections of the main vein and petiole showed that the numbers of cells in those tissues of OE plants were significantly greater.In addition,RNA-seq analysis revealed the differential expression of genes related to gibberellin synthesis and NAC gene family(genes containing the NAC domain)between the OE and WT plants,suggesting that LMI1 is involved in secondary wall formation and cell proliferation,which promotes stem thickening.Moreover,Gene Ontology(GO)analysis revealed enrichment in the terms of calcium ion binding,and Kyoto Encyclopedia of Genes and Genomes(KEGG)analysis showed enrichment in the terms of fatty acid degradation,phosphatidylinositol signal transduction system,and c AMP(cyclic adenosine monophosphate)signal pathway.These results suggested that LMI1 OE plants are responsive to gibberellin hormone signals,and have altered messenger signals(c AMP,Ca^(2+))which amplify this function,to promote stronger aboveground vegetative growth.This study found the LMI1 greatly increased the vegetative growth in cotton,which is the basic requirement for higher yield.
基金Supported by Agricultural Environment and Ecosystem Protection Program of Ministry of Agriculture of the People's Republic of China(2110402-201258)Agricultural Science and Technology Achievement Transformation and Promotion Program of Tianjin City(201203030)Cooperation Project of China and Canada(IPNI,Tianjin-2011)~~
文摘ObjectiveThis study aimed to investigate the effect of the interactions among potassium (K), calcium (Ca) and sodium (Na) on cabbage growth and nutrient absorption. MethodA total of 11 treatments with different levels of K, Ca and Na were set in the pot experiment to measure the nutrient content and uptake in cabbage plants. ResultThe use of K or the combined use of K and Ca improved the cabbage absorption on K and Ca. In addition, K and Ca presented an interaction as that appropriate amount of Ca promoted K uptake while excessive Ca inhibited the uptake. The treatment of Ca 2 K 3 with 0.33 g/pot of Ca and 0.67 g/pot of K could significantly increase the quantity of dry matter accumulation and absorption of Ca and K in cabbage, was the best among all treatments. ConclusionApplication of suitable amount of Ca could release the Na stress on cabbage growth at the low level of Na in soil.
基金funded by the National Basic Research Program of China (973 Program, 2014CB954301)the Project of the State Key Laboratory of Earth Surface Processes and Resources Ecology, Beijing Normal University, China (2013-KF-11)the Project of Ministry of Environmental Protection of China (257228006)
文摘Climate change and human activity have resulted in increasing change of vegetation growth globally. Numerous studies have been conducted on extreme climate events and analyses of ecological environment evolution. However, such studies have placed little emphasis on vegetation change and spatial variation in this type of ecotone. Accordingly, this study analyzed the changes in vegetation type and growth using the 16-d composite MOD13A1 product with 1-km resolution and MOD12Q1 product with 1-km resolution. We used the mean, maximum, standard deviation normalized-difference vegetation index(NDVI) values, and the rate of change(ROC) of NDVI value to explain vegetation changes within the studied ecotone. Our results showed that significant vegetation type and growth changes have occurred in the study area. From 2001 to 2013, for example, with the exception of 2001, 2004 and 2009, a certain extent of grassland area was converted to cropland. Drought severity index(DSI) results indicate that there exists drought in 2001, 2004 and 2009. Such temporal changes in cropland and grassland area confirmed the ecological vulnerability of the ecotone. At the same time, vegetation varied spatially from west to east and from south to north. The mean, maximum and standard deviation NDVI values were all sorted in descending order based on differences in latitude and longitude, as follows: NDVI_(2013)〉NDVI_(2009)〉NDVI_(2004)〉NDVI_(2001)
文摘Tiffs paper reports the effects of moso bamboo (Phyllostachys pubescense) vinegar, with different diluents, on the growth of lettuce, cole and cucumber based on field tests. The results show that moso bamboo vinegar with 500-800 times dilution had good effect on the growth of tested vegetables. The harvest of vegetables increased from 18.8%-20.2% compared with a control. The height and the weight of the average single vegetable tested also increased. The main components of moso bamboo vinegar were analyzed by GC-MS and the positive effect on the growth was, in the first instance, attributed to a synergistic effect of trace amounts of the main components of bamboo vinegar.
文摘Vegetative growth of young apple trees trained in vertical axis were studied with ' Red Fuji', 'Jonagold', 'Orin' and ' Starkrimson' on M7, MM106, M26 interstocks in northern China. About 30 branches sprouted from the central leader of the trees during the 4 years after planting for ' Red Fuji' and 'Jonagold', and 26.7 and 20 branches respectively for 'Orin' and 'Starkrimson'. Moreover the 2-year-old section of the central leader had the strongest capacity to sprout new branches (and sometimes the 1-year-old section too), and sprouted more new shoots than the other section. The total new shoots including spurs on the 4-year-old trees reached 631 per tree for 'Jonagold', about 480 for 'Red Fuji' and 'Orin', and 312 for 'Starkrimson'. Percentage of spurs was about 61% for 'Red Fuji', 73% for 'Jonagold' and 'Orin', and 81% for 'Starkrimson'. Growth vigor of the central leader and limbs of the young apple trees could quickly decline: the growth of the central leader decreased markedly in the fourth year after planting, and branches from the central leader grew vigorously only in the current growth season or in the first two years after branching.
文摘The leafing rates of fourteen rice varieties were measured in a sowing-time experiment, and a rapid leafing genotype at the vegetative growth stage was discovered in an indica variety Yanhui 559. The leaf number on the main culm of Yanhui 559 was always 4-5 leaves more than that of Lemont, and the leafing rate of Yanhui 559 was significantly higher than that of Lemont based on similar growth durations from sowing to heading. Furthermore, the difference of the leafing rate was significant at the vegetative growth stage, but not distinctive at the panicle initiation stage. Genetic analysis of the leafing rates in the two backcross populations of Yanhui 559 and Lemont showed that major and quantitative genes controlled the expression of rapid leafing character. Based on results of investigation for some plants with similar growth durations in the backcrossing populations, the rapid leafing genotypes exhibited earlier tillering and more tiller numbers per plant, and its yield components including the number of panicles per plant and number of grains per panicle were superior to those of the slow leafing genotypes. Further research and application feasibility of the rapid leafing genotype in breeding were discussed.
基金Supported by Suzhou Agricultural Science and Technology Project(SNG2018093).
文摘[Objectives]This study was conducted to investigate the physiological mechanism of the response of Dahlia pinnata to exogenous uniconazole during vegetative growth.[Methods]The effects of different concentrations(20,30,60 and 80 mg/L)of foliar fertilization on stem and leaf growth,chlorophyll and endogenous hormone contents were investigated using dahlia seedlings(cultivar‘Shiwucaiqiu’)cultivated in the open field.[Results]Different concentrations of uniconazole could make dahlia plants dwarf,shorten internodes,increase stem diameter,and deepen leaf color,and the higher the application concentration,the more significant the effects.Compared with the control group,the relative contents of chlorophyll(SPAD value)in various treatment groups increased,the contents of endogenous GA_(3) and IAA decreased,and the contents of ABA increased.Among them,the contents of IAA and ABA also showed a trend of increasing first and then decreasing.[Conclusions]The results indicated that uniconazole could affect the growth of stems and leaves and plant type by regulating photosynthetic pigments and the levels of endogenous hormones in dahlia,and good dwarfing effect and ornamental value could be obtained under the condition of foliar application concentration of 30 mg/L.This study provides a new experimental basis for the cultivation and application of dahlia.
文摘Two field trials were clone to evaluate the effects of plant density on the growth, development and yield of safflower. The results showed that plant density and season of growth had significant (P ≤ 0.01) effects on growth, development, yield components, yield and oil content of safflower. Increasing safflower plant density from 100,000 to 250,000 plants ha^- significantly reduced plant height (13.2%-21.3%), branch number plant^-1 (37%-54.7%), leaf number plant^-1 (39%-39.2%), leaf area (19.5%-53%), plant spread (39.6%-54.4%), root length (28.1%-54.4%), plant biomass (17%-50%), capitula size (12%-12.7%), capitula number plant^-1 (39.5%-50.5%), seed number capitula~ (39%-45%), capitula weight (3.3%-3.6%), seed yield (67.9%-69.8%) and seed oil content (14.7%-20.8%). The reduction in vegetative growth, yield components, yield and oil content of safflower due to increased plant density was attributed to inter and intra-plant competition for light, nutrients and water necessary for growth and development. The differences between winter and summer grown safflower were attributed to difference in day and night temperature (DIF) and the average daily temperature which were optimum for safflower growth in winter. It was concluded that under Botswana conditions or in semi-arid areas, safflower should be planted at 50 cm × 20 cm or wider in order to maximize yield and oil content and allow the plants to express their maximum genetic potential.
文摘Centella asiatica (L.) is commonly known as Thankuni plant and has ethnobotanical importance in Bangladesh. Present experiment was conceded to investigate the wilt disease of C. asiatica, vegetative growth and molecular characterization of pathogenic fungi. Pathogenic fungus, Fusarium equiseti was identified as a causal agent of wilt disease in C. asiatica. The effect of culture media on the mycelial growth of F. equiseti showed the highest (89.25 mm) on potato dextrose agar (PDA) medium followed by carrot agar (CA) medium and the lowest growth (40.25 mm) was measured in HA medium. The optimal temperature and pH for mycelial growth of F. equiseti were 30°C and 7, respectively. The genetic variation of the selected species of fungi, the internal transcribed spacer (ITS) region was amplified using ITS4 and ITS5 primers and sequenced. The PCR product of the ITS region of F. equiseti was 535 bp. Phylogenetic tree of thirty-seven strains of Fusarium sp. based on the nucleotide sequences of the ITS region using the neighbor-joining method with 1000 bootstrapping indicated that 98% - 100% identity with MN886590.1 JUF0046 (F. equiseti). ITS sequences are generally constant, or show little variation within species, but vary between species in a genus. The ITS region is relatively short and can be easily amplified by PCR using universal single primer pairs. Genetic distance exhibited high level of similarity with identical ITS sequences. To date, no published research articles are found on the molecular identification of F. equiseti, the causal agent of fusarium wilt disease of C. asiatica in Bangladesh.
文摘The response of grain yield, biomass yield and harvest index of maize to the application of commercial organic ameliorants was inconsistent and poor. Hence it was hypothesized that the supply of N and P to maize plants was inadequate during vegetative growth, resulting in low concentrations of the two nutrients in maize biomass. The effects of nine ameliorants on the N and P concentrations of maize plants at ninth leaf (V9) and silking (R1) stages of maize were studied over three years at Bothaville (8% clay), Ottosdal (12% clay) and Potchefstroom (34% clay). All ameliorants were applied as prescribed by manufacturers. The N and P concentrations in maize biomass of the ameliorants at V9 and R1 were lower, comparable or higher, showing that the inconsistent and poor response of yield parameters can not be ascribed to inadequate uptake of N and P. A matter of concern that justifies thorough investigation, is the prescribed use of Crop care and Growmor with partial and of Montys and Promis with no NPK fertilization, an unsustainable practice over the long term. Characterization of the active ingredient(s) of the ameliorants is deemed also of importance for better insight.
文摘In order to find out a new way for environment-friendly and resourcelized utilization of cassava starch processing wastewater, the cassava starch anaerobic fermentation liquid was applied in watermelon production, and its effects on the growth and development, yield and fruit quality of watermelon were investigated. The results showed that the cassava starch anaerobic fermentation liquid significant- ly promoted the vegetative and reproductive growth and improved the yield and fruit quality of watermelon. Compared with conventional fertilization, the application of cassava starch anaerobic fermentation both with COD concentration of 1 200 mg/L according to the amount of 150 t/hm2 promoted the growth of vines and leaves of watermelon plants, brought forward the flowering, fruiting and harvest of watermelon and significantly increased the fruit number, fruit weight, yield, fruit size, fruit shape index, soluble solid content, soluble sugar content, soluble protein content and Vita- min C content of watermelon. At the same time of improving the yield and quality of watermelon, cassava starch anaerobic fermentation liquid was turned into treasure as a liquid fertilizer. This study provides a new ideal for the yield and quality im- provement of watermelon and the wastewater treating of starch factories.
基金produced under the scientific project VEGA 1/0207/17–Development and changes of mountain landscape of the Tatrasthe tarn,and to what extent the anthropogenic factors and climate change make them conditional
文摘According to scientific evidence in general, the disappearance of the Tatras tarns as a result of external geomorphological processes has been accepted since the long term analyses of lake sediments and peat bogs, geomorphological mapping, geophysical measurements(– all indirect methods). It is paradoxical that the direct cartographic evidence of such changes has not existed until now. In this paper, we evaluate shore line changes of the small mountain glacial lake in the High Tatras-Litworowy Staw lake using a multitemporal analysis of a series of historical orthophotomaps and a historical map. Over the last 100 years, the tarn has lost 46.4% of open water level area. Significant visual changes were caused by vegetation growth of Carex species(sedges) on the water's surface. The accumulation of fine sediments and dead plant residues in the tarn basin create suitable conditions for this process, all together causing the tarn to become more shallow.
基金State Key Laboratory of Aridland Crop Science,Gansu Agricultural University(GSCS-2019-Z05)China Agricultural Research System of the Ministry of Finance(MOF)and Ministry of Agriculture and Rural Affairs(MARA)(CARS-3-2-47)。
文摘Straw strip mulching(SM)is a new mulching technology.From 2012 to 2018,SM’s effects on soil moisture and temperature and production performances were compared with other mulching practices,using three treatments:full-cover plastic mulch(PM),no mulch with wheat sown in rows as the control(CK),and SM with 50%to 59%of the field area mulched.Compared with CK,on average over six growing seasons,SM and PM increased grain yield by 27.0%and 21.7%,straw yield by 21.6%and 22.6%,kernels ha;by 26.6%and 19.0%,net income by 29.8%and-25.0%,soil temperature at 5 cm by-1.5°C and 0.2°C from overwintering to maturity,and soil water storage at 0–200 cm by 25 and 22 mm,respectively.The increase in soil moisture in SM and PM was greater in the early period(overwintering to jointing)than in the later period(booting to maturity)and at 0 to 120 cm than at 120–200 cm in the early period.Although the mean evapotranspiration of whole growth period across six seasons was similar among treatments,SM and PM increased water consumption during the key formation period of yield components after overwintering by 16 and 32 mm,respectively,while reducing it before overwintering.Compared with CK,SM and PM had the effects of warming during overwintering and cooling after jointing.By increasing water consumption after overwintering and ratio of transpiration to evapotranspiration and providing favorable soil temperature for multiple growth stages and more sufficient soil moisture,SM and PM promoted vegetative growth and increased kernels ha^(-1),the main mechanisms by which SM and PM increased grain yield relative to CK.Relative to PM,SM is a more economically beneficial and environment-friendly technology for dryland wheat production.
文摘There are documentary records referring to paclobutrazol(PBZ)as a growth bioregulator that inhibits the gibberellin synthesis and its application increases yields in fruit and vegetable crop productions.Its agronomic management includes it as an emerging technology to reduce vigour,promote flower induction and flower development in fruit trees with increased economic returns.Its use is banned in some countries because of concerns about residues that can cause harmful effects on the environment.Therefore,the aim of this article was to collect,analyse and summarise relevant information on the use of PBZ in fruit tree production and its possible risks to the environment.The results obtained indicated that the application of PBZ can be effective in solving some problems related to flowering if it is applied in the right amount and at the right time.However,it is necessary to elucidate the physiological processes with which it is associated and its response to be taken into account to increase yield.PBZ is currently used in fruit trees such as mango,lime,apple and guava,increasing their productivity.However,some studies have shown its residual effect on the environment.Therefore,PBZ is a viable strategy,because it presents a series of advantages in the production of fruit trees.However,it is vital to generate protocols that seek its regulation with a rational and sustainable approach.
基金supported by the National Natural Science Foundation of China(Grant No.30871497)the National High Technology Research and Development Program of China(Grant No.2009AA101101)the Program of Introducing Talents of Discipline to University(Grant No.B08025)
文摘Heading date of 26 native japonica rice cultivars in southwest China was investigated,and their basic vegetative growth(BVG),photoperiod-sensitivity(PS) and temperature-sensitivity(TS) were analyzed under artificial short-day and natural long-day conditions in Nanjing,as well as artificial high-temperature and natural low-temperature conditions in winter in Hainan.The results showed that the PS and TS varied among different cultivars.The BVG of all the japonica cultivars was well situated,but differed within cultivars.Regression analysis showed a significant correlation between heading date and PS,indicating that PS was the main factor affecting heading date of japonica cultivars in southwest China.Genetic analysis was conducted on these 26 cultivars using a set of heading date near isogenic lines as test lines.All the japonica cultivars carried the dominant early-heading gene Ef-1 or Ef-1t,and most of these cultivars carried the dominant photoperiod sensitivity allele E1 or E1t,the PS of which was slightly weaker than E1.For the Se-1 locus,these cultivars mainly carried recessive photoperiod insensitivity gene Se-1e.In addition,the PS of 22 japonica cultivars could be repressed or weakened by the recessive allele hd2,inhibiting the expression of E1 and Se-1.These results indicated that the genotypes of heading date determined different PS and well situated BVG in japonica rice cultivars in southwest China.