水、旱栽培条件下稻米主要品质性状的比较研究

以旱稻品种IRAT109与水稻品种越富杂交构建的DH群体的116个株系及其亲本,在水、旱2种栽培条件下种植,研究了稻米加工、外观、蒸煮和营养等品质性状的变化规律及其各品质性状间的相关性。结果表明,在11个稻米品质性状中,蛋白质含量、整精米率、胶稠度和碱消值等4个性状,水、旱2种不同栽培条件下差异较大,说明这些性状受水分条件影响较大;粒长、粒宽、直链淀粉含量和垩白率也有一定的差异,一定程度受土壤水分环境影响。旱栽条件下稻米蛋白质含量、整精米率、胶稠度、碱消值等均有不同程度的升高,其中蛋白质含量平均提高37.9%,平均增加3.02个含量百分点,而垩白率下降,稻米米粒变小,总体上旱栽稻米品质有变优趋势。糙米率、精米率和长宽比在2种栽培条件下没有差异,基本上不受土壤水分环境影响。此外,对同一品质性状在水、旱2种不同栽培条件下相关性分析,表明加工品质性状的基因与环境互作较大,外观、蒸煮和营养等品质性状比较稳定。因此,通过水稻和旱稻相互杂交,可将旱稻的抗旱基因导入外观品质、蒸煮、食用品质以及营养品质优良的目标水稻亲本中,选育出抗旱、优质的水稻或旱稻品种。

水、旱栽培条件下稻米品质性状比较研究

选用旱稻品种IRAT109和水稻品种越富重组自交系(RILs)群体(110个株系)及其亲本,在水、旱2种条件下种植,对各品种稻米的食味品质(直链淀粉含量和RVA谱特征值)和外观品质(粒长、粒宽、垩白率、百粒重)进行比较研究,并进行显著性分析,为抗旱育种和水稻育种提供理论依据。结果表明,粒宽和百粒重受水分胁迫影响较大,土壤水分对粒长、垩白率、直链淀粉含量影响较小。在旱地种植亲本和各品系的粒长、粒宽和百粒重的均值均小于水田种植,而直链淀粉含量和垩白率均大于水田种植;稻米淀粉黏滞性(RVA谱)特征谱中冷胶黏度(CPV)、消碱值(SBV)、回复值(CSV)受土壤水分胁迫影响较大,土壤水分对糊化温度(PAT)、峰值时间(PET)、最高黏度(PKV)、热浆黏度(HPV)、崩解值(BDV)影响较小。对不同品质性状间进行相关性分析,结果表明,水田种植条件下有21对品质性状呈显著相关,在旱地种植条件下14对品质性状呈显著相关,其中在2种栽培条件下均表现为显著相关的品质性状有12对。

浅谈如何加大旱春玉米种植助力乡村振兴

玉米作为我国的一个主要的粮食作物,它的产量与质量能够直接关系到我国的粮食安全,为了更好地保障我国的粮食安全,为农民提高收益,增加在玉米种植方面的生产效益,需要加大对于汉玉米的种植,使旱春玉米的整体种植水平以及玉米的效益能够显著提升,实现为农民增收,帮助农民实现脱贫致富,使农民能够过上美好的生活。本篇文章基于乡村振兴背景之下的旱春玉米种植展开研究,希望能够解决在当前旱春玉米种植上仍然存在的一些问题,为农民扩大收益。

冷凉山区旱半夏人工种植技术探析

旱半夏为天南星科多年生草本植物的块茎,又名:三叶半夏;半月莲;三步跳等,是一味传统常用中药材,有两千多年的药用历史,为国内外市场所青睐,近年来对旱半夏的需求呈逐年增长之势,但由于野生资源缺口大,导致市场价格逐年上涨,需求逐年增长,增幅很大。兴义市旱半夏人工种植主要在高海拨冷凉山区,种植面积近千亩,旱半夏种植初具规模,为了提高旱半夏人工种植产量和品质,结合生产实际,提出适宜兴义市冷凉山区的人工种植技术。

抗旱粳稻品种(组合)筛选及评价

为筛选适宜云南省稻区种植的耐旱粳稻新品种（组合）,通过对水作和旱作栽培模式下与作物生产密切相关的产量性状和农艺性状指标进行比较研究,探讨了24个粳稻品种（组合）的抗旱性.结果表明,粳稻旱作较水作苗高、分蘖数和株高降低,地上部生物量明显减少;根变长,根茎比明显增大,地下部生物量明显增加;穗长缩短,产量降低,影响旱作水稻产量的主要因子是单株有效穗和每穗实粒数.通过抗旱力指数法和农艺性状的综合评价,从中筛选出粳型抗旱常规稻品种11个、粳型抗旱杂交稻品种（组合）7个,分别为云粳30号、滇杂46、保粳杂2号、滇杂31、H149、H150、昌优13号、糯谷、云粳恢7号和云光109,在水、旱作条件下产量均稳定,抗旱系数为0.70～0.85,综合性状优,是适宜旱作的品系.

抗旱高产小麦新品种菏麦17选育及其栽培技术

菏麦17(原代号菏麦97-28)是菏泽市农业科学院与山东省科源种业有限公司培育的抗旱高产小麦新品种,2011年9月通过山东省农作物品种审定委员会审定。该品种适宜在山东全省旱肥地块种植利用。

旱塬地冬小麦播种密度试验研究

通过试验认定决定产量的主因是有效穗;播种密度30万粒产量最高为3155.7kg/hm^2,较45万粒增产20.99%;其次是35万粒,25万粒与40万粒产量相近居第3;旱塬地冬小麦合理播种密度可确定为25~35万粒。

Quantifying Responses of Winter Wheat Physiological Processes to Soil Water Stress for Use in Growth Simulation Modeling

A deep understanding of crop-water eco-physiological relations is the basis for quantifying plant physiological responses to soil water stress. Pot experiments were conducted to investigate the winter wheat crop-water relations under both drought and waterlogging conditions in two sequential growing seasons from 2000 to 2002, and then the data were used to develop and validate models simulating the responses of winter wheat growth to drought and waterlogging stress. The experiment consisted of four treatments, waterlogging (keep 1 to 2 cm water layer depth above soil surface), control (70%-80% field capacity), light drought (40%-50% field capacity) and severe drought (30%-40% field capacity) with six replicates at five stages in the 2000-2001 growth season. Three soil water content treatments (waterlogging, control and drought) with two replicates were designed in the 2001-2002 growth season. Waterlogging and control treatments are the same as in the 2000-2001 growth season. For the drought treatment, no water was supplied and the soil moisture decreased from field capacity to wilting point. Leaf net photosynthetic rate, transpiration rate, predawn leaf water potential, soil water potential, soil water content and dry matter weight of individual organs were measured. Based on crop-water eco-physiological relations, drought and waterlogging stress factors for winter wheat growth simulation model were put forward. Drought stress factors integrated soil water availability, the sensitivity of different development stages and the difference between physiological processes (such as photosynthesis, transpiration and partitioning). The quantification of waterlogging stress factor considered different crop species, soil water status, waterlogging days and sensitivity at different growth stages. Data sets from the pot experiments revealed favorable performance reliability for the simulation sub-models with the drought and waterlogging stress factors.

Developing Wheat for Improved Yield and Adaptation Under a Changing Climate： Optimization of a Few Key Genes

Wheat grown under rain-fed conditions is often affected by drought worldwide. Future projections from a climate simulation model predict that the combined effects of increasing temperature and changing rainfall patterns will aggravate this drought scenario and may significantly reduce wheat yields unless appropriate varieties are adopted. Wheat is adapted to a wide range of environments due to the diversity in its phenology genes. Wheat phenology offers the opportunity to fight against drought by modifying crop developmental phases according to water availability in target environments. This review summa- rizes recent advances in wheat phenology research, including vernalization （Vrn）, photoperiod （Ppd）, and also dwarfing （Rht） genes. The alleles, haplotypes, and copy number variation identified for Vrn and Ppd genes respond differently in different climatic conditions, and thus could alter not only the development phases but also the yield. Compared with the model plant Arabidopsis, more phenology genes have not yet been identified in wheat; quantifying their effects in target environments would benefit the breeding of wheat for improved drought tolerance. Hence, there is scope to maximize yields in water-limited envi-ronments by deploying appropriate phenology gene combinations along with Rht genes and other important physiological traits that are associated with drought resistance.

Symbiotic and Phenotypic Characteristics of Rhizobia Nodulaing Cowpea （Vigna Unguiculata L. Walp） Grown in Arid Region of Libya （Fezzan）

Symbiotic and phenotypic characteristics of thirty rhiobial isolates obtained from root nodules of two cowpea （Vigna unguiculata L. Walp） cultivars that grown in different sites of Fezzan （Southern part of Libya） were studied. Cultural characteristics and cross-nodulation with Arachis hypogega and Faidherbia albida showed that they were slow-growing rhizobia. Each isolate was found to coexist with non-symbiotic bacteria similar in their cultural characteristics to fast-growing rhizobia. All isolates formed symbiosis with the test plants, but different in their nitrogen-fixation efficiency. Numerical analysis of phenotypic characteristics showed that at boundary level of 70% average similarity, the isolates formed four distinguished groups and two isolates remained separate. Most isolates exhibited wide tolerance to acidity, alkalinity and extreme temperatures. They also resistant to some heavy metals such as mercury, copper, zinc, lead, cadmium and aluminum at low concentrations and antibiotics like polymyxin, colistin, bacitracin and nalidixic acid. Isolates displayed different response to salinity ranging from sensitive, which unable to grow in 1% NaCI to resistant and grow at 2% NaCl or above. Urea was hydrolyzed by most of them and carbohydrates utilizations were different. Sucrose and maltose were metabolized by most of the test isolates, whereas, monosaccharide and sugar alcohols were poorly utilized.

Status Analysis of Tobacco Production in Chifeng City

With the slowdown of China economy during 2011-2015, tobacco growing areas were compressing year by year.At the same time, because of the decrease of potassium to chlorine ratio, Chifeng tobacco leaves were no longer as high quality supplying materials in cigarettes of Shanghai Tobacco （Group）. And thus, the allocation amount of Chifeng tobacco leaves were reduced. It is necessary to highlight local tobacco characteristics and improve tobacco quality for sustainable development. This research, therefore, reviewed tobacco planting, natural characters, potassium/chlorine rate and proposed suggestions.

Contribution of Promiscuous Soybean （Glycine max L.） to Upland Rice-based Cropping Systems in West Africa

A two-year on-farm study was carried out at Eglime in the moist savanna （MS） and Ouake in the dry savanna （DS） of Benin to evaluate the contribution of inoculation of dual-purpose soybean varieties to grain yield of upland NERICA rice fertilized with low N level. In 2005, four dual-purpose, promiscuous soybean varieties （cv. TGx1440-IE; TG×1448-2E; TG×1019-2EB; and TG×1844-18E）, and a popular improved variety （cv. Jupiter） were sown in 12 farmer fields with and without Bradyrhizobium japonicum inoculation. There was also land which was left fallow that acted as the control. In 2006, upland interspecific rice （NERICA 1） was sown in all the plots and supplied with 15 kg N haL. Dry matter yield, N accumulation, and net N-balance were significantly enhanced by over 40% with inoculation of cv. TG× 1844-18E than non-inoculation in the DS in comparison to other cultivars. There were no significant effects of inoculation of previous soybean cultivars on soybean grain yield and on the succeeding NERICA rice yield. Averaged over inoculation, previous cv. TG× 1019-2EB plots supplied with only 15 kg N hal gave the highest grain yield, more than twice the yield of control plots in the DS, possibly because of significant production of higher tillers, panicles and harvest index than the other cultivars; and it could be recommended for upland rice-based system for NERICA production.

Influence of Cropping Systems on Soil Properties in Semi-arid Conditions of Setif, Algeria

The effects of two culture systems, conventional and no-till combined the previous crop （lentil and wheat） on soil properties were studied in the experimental site of the station Technical Institute for Field Crops （ITGC） Setif （Algeria） during the crop year 2011/2012. The results indicate that the no-till system affects positively the variables of soil properties and the organic matter has a rate of 2.89% compared to 2.44% in conventional tillage. If the conventional system has an infiltration of moisture relatively higher than that observed for no-till throughout the cycle, the no-tillage is distinguished by a higher storage of moisture at the end of cycle wheat cultivation. The results also indicate that the density （1.44 g/cm）, permeability （22.79 cm/h） and soil compaction （12.51 kg/cm） in no-till were significantly higher compared to conventional tillage 1.35 g/cm, 14.13 cm/h, 7.40 kg/cm, respectively.

Above-ground Biomass Allocation in a Planted Forest in a Semi-arid Region of Northern Mongolia

Investigation of the above-ground biomass allocation patterns on Scots pine plantations is critical for quantifying the productivity and carbon cycle of forest ecosystems. We estimated above-ground biomass and net primary production of a 25-year-old Pinus sylvestris L. （Scots pine） plantation, in a semi-arid region of Mongolia. The above-ground biomass of sample trees was divided into stem wood, stem bark, live branches, dead branches and needles. Total biomass for the stand was only 18.03 Mg ha1, of which 47.6% was found in stem wood, 25.8% in live branches and 14.8% in needles. The growth rate of the Scots pine plantation in the study region was relatively low compared with other regions. In the study area, it was observed that the rate of biomass accumulation in the plantation was very slow; this can be explained by very limited growing conditions and intensive crown closure. The results from this study indicate that it may be necessary to carry out thinning to increase biomass production by reducing competition between trees in the Scotch pine plantation.

The Effects of Cropping Methods on Growth, Crop Index and Yield Response to Water of Rice （Oryza sativa L.） in Rainfed Agriculture

In this study, four combinations of crops： rice （C）, rice-maize （MCSI）, rice-cassava （MCS2） and rice-maize-cassava （MCS3） with 3 m × 3 m each plots at two field areas--Saptosari and Tanjungsari were observed. Both field areas are located in Gunungkidul district, South-Central of Java Island, with that 93% at those areas are 185 m to 500 m above sea level and high proportion of multiple cropping systems （MCS）. The aim of this study was to investigate the effect of different cropping method on growth, crop index and yield response to water of rice in rainfed agriculture. Mathematical models were developed to describe rice growth. The rice height was followed monomolecular function and the number of tillers followed exponential polynomial function. Crop index was calculated from climate data during plant growth phase. And yield response to water was calculated from actual evapotranspiration （ETa） and the maximum evapotranspiration （ETm）. The results showed that the height of rice was not significantly different between each combination （P 〉 0.05）. Number of tillers was also not significant （P 〉 0.05）. However, monoculture treatment had more number of tillers than rice in MCS. Crop index of rice at Saptosari was higher than at Tanjungsari. Based on the calculation of evapotranspiration （ET）, water deficit at initial was less than at mid-season （ETa 〈 ETm） and affected water stress. Statistical analysis showed that cropping methods did not significantly affect rice growth and yield （P 〉 0.05）.

Contribution of Study Bioecology of the Fauna Chamaerops humilis in the Region of Tlemcen （Algeria）

The region of Tlemcen is situated in the north-west of Algeria. The aridity of the climate had lead to the development of the matorral, a state of degradation of the Mediterranean, and the composed xerophytes plants such as doum and diss, had been found. Chamaerops humilis, xerophyte plant, with special morphologic and botanic character presents a resistance of these climatic. The authors have proposed study of fauna closly linked to this plant. A faunistic inventory was realized in the Mansourah area （region of Tlemcen）. Four stations have been described. Collecting sample was performed during June 2003-Mar. 2004, replying on sixteen （16） prelevements. The number of species were estimated of about 136, in which 111 are Arthropoda, the Entomofauna represented by 97 species and the other inventory are Arachnida by 8 species and Myriapoda by 6 species. 18 species are related to Gastropoda. The vertebrates are few. The importance of different groups＇ recolted on the Chamaerops humilis in the four stations is done particular to the insects. Analysis factorial correspondence （A.F.C） show different grouping of animal species.

Relationships between Agronomic Practices, Soil Chemical Characteristics and Striga Reproduction in Dryland Areas of Tanzania

The parasitic weed Striga poses a serious threat to cereal production in sub-Saharan Africa. For many years, technological packages for the control of this weed were proposed and implemented on farmers＇ fields. A survey was carried out in farmers＇ fields in 2010/201l cropping season in selected dryland areas of Tanzania to： （a） determine the Striga plant counts, number of capsules/Striga plant and agronomic practices used by farmers to control Striga; and （b） evaluate the relationship between Striga reproduction, soil chemical characteristics and agronomic practices. Soil samples at 0-20 cm depth were collected from 20 different farmers＇ fields. The soil samples were analyzed for pH, organic carbon, N, P and K. Results showed that there was low adoption of recommended Striga control methods. Regression analysis of agronomic practices and soil chemical characteristics revealed a positive improvement of soil N and organic carbon and reduction of soil P and K content as one shifted from sole planting to intercropping. The results showed that potassium was highly positively related to number of capsules/Striga plant. There was a reduction in the number of capsules/plant as one moved from sole planting to intercropping. Based on these findings, K in the Striga infested in soils positively influenced Striga reproduction and seed bank replenishment, hence high soil K levels may lead to high Striga incidence.

Dynamics in the emergence of dormant and non-dormant herbaceous species from the soil seed bank from a Brazilian dry forest

Aims In dry tropical forests,herbaceous species may have dormancy mechanisms and form persistent and transient seed banks in the soil.Evolutionarily acquired,these mechanisms are efficient for the establishment and survival of these herbs,especially in forests with unpredictable climates,such as the Caatinga.Thus,our objective was to verify whether the studied herbaceous species adopt the physical dormancy mechanism and how these natural barriers are overcome,to understand the temporal dynamics existing in the soil seed bank from a Brazilian dry tropical forest.Methods Seeds of five native herbaceous species from the Caatinga forests were selected and submitted to pre-germinative treatments for verifying the presence of physical dormancy.We collected soil samples in the rainy and dry seasons for four consecutive years and monitored the emergence of the selected herbaceous in the greenhouse.We verified the differences in germination and seed bank emergence in the soil by generalized linear models.Important Findings The presence and absence of physical dormancy were observed in seeds from Caatinga herbaceous species.We found intraspecific and interspecific differences in the herbaceous emergence from soil seed banks between years and climatic seasons.In perennial herbs,consecutive lack of emergence between seasons and years was frequent,which suggests a direct relationship with the mechanism of physical dormancy and the environmental conditions necessary to overcome integument barriers.In these species,seed dimorphism and dormancy may confer additional advantages to their survival.Moreover,presenting intermediate levels of physical dormancy in an annual species may be an evolutionary adjustment to rainfall unpredictability.In contrast,we found that the annual herb without dormancy is more sensitive to seasonal and interannual climate changes,as evidenced by the increase and significant reduction of its emergence in the soil seed bank.These differences acquired evolutionarily are advantageous for the establishment of herbaceous populations,mainly in semiarid regions with an unpredictable climate.