日喀则青稞品种(系)栽培试验研究

在日喀则市独特的生态环境下开展藏青13、藏青2000、13-6927春青稞新品(种)系栽培试验,全面系统分析了各品(种)系的千粒质量、穗粒数、成穗数等关键产量影响因子对青稞增产潜力的影响,以期为加快良种推广步伐和新品种区域试验和展示、示范工作,引导农民种植优质、高产、高效新品种提供科学依据。

An Efficient Method of Nuclei Extraction in Cotton

[Objective] The experiment aimed to study an efficient method of Nuclei extraction of cotton and provided technical support for constructing large-insert genomic library and sequencing complete genome. [Method] The cotton cotyledons germinated in dark moisture chamber for one week were chopped with a sharp sterile scalpel in a Petri dish which contained ice-cold nucleus isolation buffer (10 mmol/L MgSO4, 5 mmol/L KCl, 0.5 mmol/L HEPES, 1 mg/ml DTT, 0.25% Triton X-100 and 2% PVP40), then the nuclei were collected after selected through 100, 50 and 30 μm nylon meshes and centrifugation. Meanwhile, the tender leaves and cotyledons with different germination time in dark were treated by grinding method and sharp scalpel method. [Result] The chopping with a sharp scalpel method was very simple and rapid, which did not need grind and mercaptoethanol treatment and the successful extraction rate was 100%.[Conclusion] An efficient method of nuclei extraction of cotton with simple, high efficiency, rapid reaction and poison free were established.

Analysis and Evaluation Indicator Selection of Chilling Tolerance of Different Cotton Genotypes

[Objectivc] This study aimed to investigate the chilling tolerance of seedlings of different cotton genotypes and screen appropriate indicators for assess- ing chilling tolerance, to establish reliable mathematical evaluation model for chilling tolerance of cotton, thus providing theoretical basis for breeding and promoting new chilling-tolerant cotton germplasms and large-scale evaluation of chilling tolerance of cotton varieties. [Method] Fifteen cotton varieties （lines） were used as experimental materials. The photosynthetic gas exchange parameters, chlorophyll fluorescence ki- netic parameters, chlorophyll content, relative soluble sugar content, malonaldehyde content, relative proiine content, relative conductivity and other 12 physiological indi- cators of seedling leaves under low temperature treatment （5 ℃, 12 h） and recovery treatment （25 ℃. 24 h） were determined; based on the chilling tolerance coefficient （CTC） of various individual indicators, the comprehensive evaluation of chilling toler- ance was conducled by using principal component analysis, hierarchical cluster anal- ysis and stepwise regression analysis. [Result] The results showed that the 12 indi- vidual physiological indicators could be classified into 7 independent comprehensive components by principal component analysis; 15 cotton varieties （lines） were clus- tered into three categories by using membership function method and hierarchical cluster analysis; the mathematical model for evaluating chilling tolerance of cotton seedlings was established： D =0.275 -0.244Fo1 ＋0.206Fv/Fm1＋0.326g,%-0.056SS ＋ 0.225MDA＋O.O38REC （FF=0.995）, and the evaluation accuracy of the equation was higher than 94.25%,0. Six identification indicators closely related to chilling tolerance were screened, including Fo,, Fv/Fm1, Seedling leaves of cotton varieties （lines） gs2, SS, MDA, and REC. [Conclusion] with high chilling tolerance are less dam- aged under low temperature stress, and are able to maintain relatively high photo- synthetic electron transport capacity and high stomatal conductance after recovery treatment, which is contributed to gas exchange and recovery of photosynthetic ca- pacity. Determination of the six indicators under the same stress condition can be adopted for rapid identification and prediction of the chilling tolerance of other cotton varieties, which provides basis for the breeding, promotion, identification and screen- ing of chilling tolerant germplasms.

Identification of the Parentage of Corn Variety Using SSR Markers

[Objective] The study was to explore the molecular interpretation standards on parentage in the seeds of corn variety. [Method] With 16 hybrids and their parents and 202 inbred elites as materials for screening primers, the artificial groups of two standard diad and two standard triad were respectively established as the verification materials. Genomic DNA of seedlings was extracted by using CTAB method. 137 pairs of SSR primers were selected for SSR amplification and product detection, which was used for the parentage identification of maize varieties. [ Result] Twenty pairs of corn primers with high polymorphism information content （ PIC value）, clearly amplified bands and good reproducibility were screened from 137 pairs of corn SSR primers tested. The identification results of using SSR molecular were consistent with the actual situation. [ Conclusion] It is feasible to identify the parentage of maize variety using SSR markers.

Principal Component Analysis and Cluster Analysis of Fagopyrum tataricum Varieties(Lines)

In order to reveal the genetic differences and agronomic traits of Fagopy-rum tataricum_ varieties （lines） intuitively, explore good resources and avoid the blindness of parent selection during the breeding process, six primary agronomic traits of 45 F. tataricum_ varieties （lines） that came from the eleven buckwheat breeding departments across the country were analyzed with principal component analysis and cluster analysis. The results of principal component analysis showed that the six agronomic traits could be simplified into three principal components, and the cumulative contribution rate reached 83%. The results of cluster analysis showed that the 45 F. tataricum varieties （lines） were classified into four groups：high stalk, medium yield and smal grain type, medium stalk, high yield and large grain type, medium stalk, low yield and smal grain type and high stalk, medium yield and medium grain type. Among them, performance of comprehensive trait of the second type was better than that of the other types. Thus, the F. tataricum_va-rieties （lines） that were classified into the second type could be considered as good varieties （lines） or breeding materials. The genetic differences among F. tataricum_varieties （lines） had no necessary correlations with origin and geographical distance. ln addition to complementary traits and geographical distance, genetic distances （dif-ferent populations） should be taken into consideration during parent selection in cross breeding.

The Construction of Heat-resistant Near Isogenic Line (NIL) of Bombyx mori and the Development of Molecular Marker Breeding Technique

[Objective] The study aimed to provide theoretical basis for development and application of molecular marker breeding technique to obtain Bombyx mori near-isogenic lines （NILs）. [Method] Thermotolerance gene was introduced into sensitive variety Ou17 by developing NILs and recurrent backcross,then through six generations of backcross,thermotolerance-assisted selection,and two generations of self-cross. [Result] Bombyx mori NILs carrying thermotolerance gene （new germplasm） were produced. Meanwhile,thermotolerance level of progenies of each backcross and molecular markers of NILs were determined,and then attempts were made to produce practical thermotolerance hybrids by using thermotolerance varieties whose thermotolerance gene is linked to SSR markers. [Conclusion] The study successfully construct thermotolerance NILs,monitor thermotolerance level and breeding results of progenies of each backcross,and determine molecular marker of NILs.

Breeding of a Natural Colored-Cocoon Bombyx mori Variety Shuhuang No.1

[Objective] This study aimed to develop a new Bombyx mori variety Shuhuang No.1 and investigate its characteristics.[Method] The new variety was developed through cross breeding and pedigree separation.Its characteristics were identified by laboratory tests and rural promotion practices in Sichuan Province.[Result]The cocoon produced by the new variety Shuhuang No.1 was golden-yellow and radiantly beautiful.Shuhuang No.1 was strong and easy to rear,uniform in development.The male and female ones could be distinguished by their larval color and markings.The cocoon yield per 10 000 the 4th instar larvae reached 20.30 kg; the length of a cocoon filament was about 1 115.0 m,and a non-broken filament was 882.95 mm long,accounting for 79.15％ of the total length.The raw silk ratio of fresh cocoon was 18.39％,and the neatness was 91.25 point.The main economic features of Shuhuang No.1 were better than those of the control.[Conclusion] The new variety had been approved by Sichuan Silkworm Evaluation Commission.It can be promoted in parent silkworm rearing areas Sichuan,Chongqing,Yangtze River basin.

Comparison of Absorption Capacity of Different Flue-cured Tobacco Cultivars for Six Kinds of Heavy Metals

[Objective] This study aimed to analyze the differences in absorption capacity of different flue-cured tobacco cultivars for chromium （Cr）, arsenic （As）, cadmium （Cd）, lead （Pb）, mercury （Hg） and copper （Cu）. [Method] With 4 flue-cured tobacco cultivars as the experimental materials, their absorption capacity for 6 kinds of heavy metals was compared by pot experiment. [Result] There were great differences in absorption capacity of different flue-cured tobacco cultivars for the six kinds of heavy metals. According to the absorption capacity of different flue-cured tobacco cultivars for the heavy metals, the six heavy metals could be classified into three categories. The first category included only Cd with average enrichment coefficient of 8.564; the second category included Hg with average enrichment coefficient of 0.753; and the third category included Cr, As, Pb and Cu with average enrichment coefficients below or equivalent to 0.114. [Conclusion] The absorption capacity of different flue-cured tobacco cultivars for heavy metals was grasped by this study, thereby providing reference data for screening of high-yielding and high-quality flue-cured tobacco cultivars.

Root Physiological and Morphological Characteristics of Two Rice Cultivars with Different Nitrogen-Use Efficiency

The variation in nitrogen （N） uptake by rice has been widely studied but differences in rice root morphology that may contribute to this variation are not completely understood. Field and greenhouse experiments were carried out to study N accumulation, root dry weights, total root lengths, root surface areas, and root bleeding rates of two rice cultivars, Elio with low N-use efficiency and Nanguang with high N-use efficiency. Low （1 mmol N L^-1） and high （5 mmol N L^-1） N applications were established in the greenhouse experiment, and the N rates were 0, 120, and 240 kg ha^-1 in the field experiments at Jiangning and Jiangpu farms, Nanjing, China. The results showed that the N accumulation, root dry weight, total root length, and root surface area increased with an increase in N application. At the heading stage, N accumulation in the shoots and roots of Nanguang was greater than that of Elio in the field experiments and that of Elio at 5 mmol N L^-1 in the greenhouse experiment. After the heading stage, N accumulation was higher for Nanguang at both 1 and 5 mmol N L^-1 in the greenhouse experiment. The total root length and root surface area were significantly different between the two cultivars. Over the range of the fertilizer application rates, the root lengths of Nanguang at Jiangning Farm were 49%-6170 greater at booting and 26%-39% greater at heading than those of Elio, and at Jiangpu Farm they were 22%-42% and 26%-38% greater, respectively. Nanguang had a greater root bleeding rate than Elio. It was concluded that the N-use efficiency of the two rice cultivars studied depended to a great extent on the root morphological parameters and root physiological characteristics at different growth stages.

Effect of an Alien Species Spartina alterniflora Loisel on Biogeochemical Processes of Intertidal Ecosystem in the Jiangsu Coastal Region,China

Spartina alterniflora Loisel, a species vegetating in intertidal flats along the eastern coast of the United States, was introduced in China almost 30 years ago and has become an urgent topic due to its invasiveness in the coastal zone of China. The impacts of this alien species S. alterniflora on intertidal ecosystem processes in the Jiangsu coastland were investigated by comparing the sediment nutrient availability and trace element concentration characteristics in a mud flat and those of a four-year old Spartina salt marsh that had earlier been a mudflat. At each study site, fifteen plots were sampled in different seasons to determine the sediment characteristics along the tidal flats. The results suggested that Spartina salt marsh sediments had significantly higher total N, available P, and water content, but lower pH and bulk density than mudflat sediments. Sediment salinity, water content, total N, organic C, and available P decreased along a seaward gradient in the Spartina salt marsh and increased with vegetation biomass. Furthermore, the concentrations of trace elements and some metal elements in the sediment were higher under Spartina although these increases were not significant. Also, in the Spartina marsh, some heavy metals were concentrated in the surface layer of the sediment. The Spartina salt marsh in this study was only four years old; therefore, it is suggested that further study of this allen species on a longer time frame in the Jiangsu coastland should be carried out.

Progress of safflower (Carthamus tinctorius L.) regeneration through tissue culture

Background: Safflower regeneration through tissue culture has long been limited to low frequency and lack of an efficient protocol that suitable for most safflower cultivars. In past decades, researches had been carried out to investigate safflower regeneration through tissue culture and great progress had been made. Objective: To investigate factors that affect safflower regeneration through tissue culture principally. Methods: This article summarized available literatures about advancements in safflower regeneration, especially discussed factors affecting safflower tissue culture in detail. Results: Safflower regeneration was fairly hard than other congeneric plants, such as chrysanthemum. The genotype, seedling age, type of explants, medium components, plant growth regulators and other additives all had specific influences on safflower tissue culture. More deepgoing researches need to be undertaken to establish an effective safflower regeneration system.

Are the fish of the upper and lower Mekong interconnected?

The Mekong supports one of the richest inland fisheries in the world, with many of the fish migrating long distance to spawn. Little is known about the fisheries and migration strategies of the Upper Mekong whilst it is supposed that many fish species move between the Lower and Upper Mekong. Most likely, natural fish migration in the river has been altered by dam construction across the mainstream of the Upper Mekong. In this paper, the interconnectivity of fish species between different sections of the Mekong and negative impacts of dams on migratory fish are studied. Of the 162 fish species in the Upper Mekong and the 869 species in the Lower Mekong, 61 species are common. Results show that there is no significant difference at order level between the UM and LM. Similarity coefficients are used to evaluate interconnectivity at species, genus and family levels among four different sections of the Upper Mekong with each other and with the Lower Mekong as a whole. The highest similarity is found between the middle and lower reach of the Upper Mekong at species and genus levels and the middle and upper reach at family level. Of the eight cascade dams, Mengsong Dam in planning is considered as the biggest threat to migratory fish from the Lower Mekong and should be particularly concerned.

A New Hot Pepper Cultivar Hangjiao Hongfeng

Hangjiao Hongfeng is a new hot pepper F1 hybrid cultivar which is bred with the cytoplasmic male sterile line 11066 AH as the female parent and the restoringline 11044 CH as the male parent. Its fruit is early-mid maturing and in the shape of a long finger.The immature fruit is in dark-green and mature fruit is in dark-red.The average length, width and flesh thickness are 15.7, 1.9 and 0.17 cm, respectively. The yield of dry pepper is 6 750 kg/hm^2. The average contents of Vc, soluble solid and dry matter are 1.30 mg/g, 10%, and 14% respectively. The cultivar has good resistance to pepper blight, viral disease and anthracnose. It shows strong tolerance to heat, water logging and drought. It is suitable for spring field cultivation in Gansu, Xinjiang and Inner Mongolia.

Evaluation and Performance of the APSIM Crop Growth Model for German Winter Wheat, Maize and Fieldpea Varieties in Monocropping and Intercropping Systems

Competition for solar radiation between plants grown in multi-species cropping systems can severely limit crop production of individual species within that system. There are various approaches for modeling light interception within mixed-cropping and row or strip intercropping systems. To extend the knowledge about model behavior and different model approaches under interspecific competition conditions, the Agricultural Production Systems Simulator （APSIM） was evaluated and calibrated for field experiments previously described and simulated by the Decision Support System for Agrotechnology Transfer （DSSAT）. Initially the APSIM plant model was successfully modified to simulate wheat, maize and fieldpea monocultures in the European agro-ecological zone. Once calibrated, the APSIM model was then used to simulate a strip relay intercropping maize/wheat and maize/fieldpea system. In DSSAT, a shading algorithm was introduced to modify the daily weather input in order to take competition for solar radiation into account. In contrast, APSIM simulates interspecific competition using a modified Beer＇s law for multi-component canopy conditions. After a re-evaluation of the model regarding a minimum change of crop coefficients and variables, APSIM was able to simulate dry matter and grain yield of German maize, wheat and fieldpea varieties adequately. However, APSIM is a point-based model, and many of the processes that influence strip cropping cannot be accommodated by adjusting Beer＇s Law alone. So far none of the tested frameworks successfully modeled strip or relay intercropping. The processes governing growth in the numerous and very diversifying intercropping systems are complex and at this point in time have not been captured in sufficient detail.

Analysis of Genetic Relationship of 64 Local Varieties of Morus atropurpurea Roxb.in Guangdong Based on ISSR Marker

[Objective] The study aimed at analyzing the genetic relationship of 64 local varieties of Morus atropurpurea Roxb.from the Pearl River Basin in Guangdong and Guangxi Provinces.[Method] Genetic diversity of 64 local varieties of Morus atropurpurea Roxb.was analyzed by ISSR molecular marker technique.The genetic relationship among these local varieties was researched by UPGMA method based on the genetic similarity coefficient.[Result] 128 bands were amplified from the total DNA of 64 local varieties using 13 ISSR primers,of which 109 bands accounting for 85.15% were polymorphic.It meant that there was rich genetic diversity among the local varieties tested.The genetic similarity coefficients among 64 local varieties were relatively high with a range of 0.500 0-0.929 7.In addition,64 local varieties were divided into two categories and the second could be further divided into 10 subcategories.It was suggested that the genetic relationship of 64 local varieties of Morus atropurpurea Roxb.based on ISSR marker analysis has a certain correlation with geographical distribution.[Conclusion] ISSR marker technology was suitable for evaluating genetic relationship and genetic diversity of local varieties of Morus atropurpurea Roxb.in Pearl River Basin,and could provide scientific basis for DNA fingerprinting and identification of varieties of Morus atropurpurea Roxb.

The Study of Using Near-infrared Diffuse Reflectance Spectroscopy Rapid Identify Wheat Drought Resistance-Ⅱ

[Objective] The aim was to build an evaluation method rapidly identifying wheat drought tolerance with near infrared diffuse reflectance spectroscopy. [Method] In the research, 36 wheat varieties in 2007-2009 were chosen and drought-tolerance degrees of wheat were graded and identified according to Winter-wheat Drought Tol- erance Evaluation Technical Standards （GB/T 21127-2007）, and harvest wheat grains underwent spectrum collection, with a full-spectrum analyzer, to establish a database. [Result] Based on qualitative analysis and full-spectrum correlation research, the coef- ficient of determination （RSQ） and cross-validation coefficient of determination （1-VR） were concluded at 0.697 5 and 0.600 2, showing near-infrared diffuse reflectance spectroscopy is of significant differences among wheat varieties and of significant or extremely significant correlation with drought-tolerance indices. [Conclusion] The re- search indicates that to evaluate drought-tolerance of wheat with near-infrared diffuse reflectance spectroscopy is a rapid and feasible way, which is simple, convenient without damages on grains, and of practical values for construction wheat drought-tol- erance evaluation index system and identification of breeding materials.

Research on the Adaptability of New Flue-cured Tobacco Varieties(Lines) in Ankang Tobacco Growing Area

In order to screen new flue-cured tobacco varieties （lines） with mountain characteristics of Ankang tobacco growing area, the adaptable selection experiments of 6 newly introduced flue-cured tobacco varieties （lines） were carried out at the 2 set test sites in Ankang producing areas with K326, ＇Yunyan 87＇ and ＇Qinyan 96＇ as controls. The results showed that YN105 had more leaves per plant and coordi- nate chemical composition, and the yield per unit area was 2 221.05 kg/hm2 with the single output of 33 960.00 yuan/hm^2. Its rate of high and medium class leaves was 80.17%, presenting good performances in testing varieties （lines）. The flowering of YN99 was late but showed coordinate chemical composition, and the yield per unit area was 2 128.50 kg/hm^2 with the single output of 33 454.05 yuan/hm^2. Its rate of high and medium class leaves was 83.17%, which also had good perfor- mances in testing varieties （lines）. It was recommended that YN105 and YN99 be moderate planted in Ankang tobacco growing area, but further experiment is needed to confirm.

Analysis on Some Agronomic Characters and Pedigree in Hezihao Series Peanut Varieties

The genealogical relationship and agronomic characters of 13 peanut varieties,breeded by Hezhou Academy of Agricultural Sciences,which had been authorized were analyzed.The results showed that 20 direct parents were involved in 13 varieties,80%of which came from Guangxi and Guangdong Province.Shanyou 523 and Yueyou 193 were used for more times;The genealogical analysis of these certified varieties can be traced back to 30 ancestral parents,the proportion of which contained consanguinity of Fu Peanut and Shitouqi were 84.62%.This demonstrated that genetic basis was rather narrow and it was quite difficult to make a great breakthrough in breeding.Plant height,total number of branches and oil content changed very little,100-pod weight and pod yield increased,whereas there was a downward trend in shelling percentage.Therefore,it is quite necessary to further broaden the germplasm basis of parents,enrich breeding methods,and continue to strengthen disease-resistant breeding and specific peanut breeding.

Effect of Transgenic Corn Cultivation and Sampling Location on Feeding Habits of Collembola

Transgenic corn was modified to combat lepidopteran pests, herbicide and other deteriorate environmental factors. However, fewer studies concerned the effects of transgenic corn cultivation on the soil Collembola in black soil region in China. In Jilin black soil region, a six treatments study including three corn varieties （transgenic corn, control and local variety） and two sampling locations （in rizhosphere and in between plants） were deployed to study the effect of transgenic corn cultivation and sampling location on densities, species richness and community structure of Collembola. We found that root biomass was marginally decreased in transgenic corn and control variety when compared to local variety. Collembola significantly affected by sampling location treatments. Densities and species richness of collembolans significantly decreased in ＂between plants＂ than in ＂rizhosphere＂. Densities of Collembola were impacted by corn varieties. In the whole growing season, densities of Collembola significantly decreased in control than in local variety. Collembolans in transgenic variety only slightly decreased in ＂jointing stage＂ than local variety. Collembolans adversely affected in ＂between plants＂ when compared to ＂in rhizosphere＂ in ＂seeding stage＂ but not other stages. These variations of collembolans were in lines with the trend of corn root biomass. It is indicated that Collembola variations could be caused by food resources （root biomass） but not corn varieties （transgenic, control and local）.

Yield and Quality Performance of Japonica Rice Varieties Grown in the Late Season in a Double Rice Cropping System of China

Meeting the demand for high-quality japonica rice is a major challenge facing China's grain security. In the present study, a two-year field experiment was conducted to investigate the yield, quality, and profitability of japonica rice varieties(including hybrids and inbreds) grown in the late season as compared with local elite indica hybrids in a double rice cropping system of China where indicas are traditionally planted. Indica hybrids had significantly longer vegetative(from sowing to heading) and total(from sowing to maturity) growth durations than japonicas in both2011 and 2012, while reproductive growth duration(from heading to maturity) was longer for indica hybrids than for japonicas in 2011 but not in 2012. Indica hybrids produced higher grain yield than japonicas in 2011, but with no significant differences in 2012. Japonicas had higher brown rice, milled rice, and head rice percentages than indicas, but had lower gelatinization temperature and amylose content,while with no significant differences in gel consistency and protein content. Indica hybrids tended to have lower chalky grain percentage and chalkiness degree than japonicas, though the differences were not statistically significant due to large genotypic variations. The net returns were 16.1% and 9.9% greater for indica hybrids than for japonica hybrids and japonica inbreds in 2011, with only 3.8% and 1.3% in2012, respectively. Thus, our results suggest that replacing indicas with japonica varieties as late rice may not be feasible at the present site unless locally adapted japonica varieties are developed.