Effect of Phosphorus Fertilization to P Uptake and Dry Matter Accumulation in Soybean with Different P Efficiencies

Phosphorus （P） is an essential element for plant growth and yield. Improving phosphorus use efficiency of crops could potentially reduce the application of chemical fertilizer and alleviate environmental damage. Soybean （Glycine max （L.） Merr.） is sensitive to phosphorus （P） in the whole life history. Soybean cultivars with different P efficiencies were used to study P uptake and dry matter accumulation under different P levels. Under low P conditions, the P contents of leaf in high P efficiency cultivars were greater than those in low P efficiency cultivars at the branching stage. The P accumulation in stems of high P efficiency cultivars and in leaves of low P efficiency cultivars increased with increasing P concentration at the branching stage. At the late podding stage, the P accumulation of seeds in high and low P efficiency cultivars were 22.5 and 26.0%, respectively; and at the mature stage were 69.8 and 74.2%, respectively. In average, the P accumulation in whole plants and each organ was improved by 24.4% in high P efficiency cultivars compared to low P efficiency cultivars. The biomass between high and low P efficiency cultivars were the same under extended P condition, while a significant difference was observed at late pod filling stage. At the pod setting stage, the biomass of high P efficiency cultivars were significant greater （17.4%） than those of low P efficiency cultivars under high P condition. Meanwhile, under optimum growth conditions, there was little difference ofbiomass between the two types of cultivars, however, the P agronomic efficiency and P harvest index were significant higher in high P efficiency cultivars than those in low P efficiency cultivars.

Impact of Sino-US Trade Friction on Import and Export Trade Pattern of Soybean in Heilongjiang

Under the background of Sino-US trade friction,soybean,as an important variety in the important and export trade of agricultural products,has become a key bargaining chip. After the Ministry of Commerce of China announced the counter list of agricultural products including soybean,the price fluctuations of domestic soybean and related agricultural products are rapidly expanding. Under the background of SinoUS trade friction,taking the soybean-producing areas in Heilongjiang as an example,the impact of Sino-US trade friction on the important and export pattern of soybean in Heilongjiang was explored to provide a certain theoretical basis for the development of soybean industry in Heilongjiang.

Effect of pulse drip irrigation and mulching systems on yield, quality traits and irrigation water use efficiency of soybean under sandy soil conditions

Two field experiments were carried out during growing seasons 2010 and 2011, it executed in research farm of national research center in Nubaryia region, Egypt to study the effect of pulse drip irrigation and mulching systems for saving water, increasing and improving yield of soybean. The study factors were, pulse drip irrigation technology (adding of daily water requirements on 4 times, 8 times, 12 times compared with adding of daily water requirements on 1 time) and mulching systems (covering the soil with black plastic mulch “BPM”, rice straw mulch “RSM” and the control treatment was soil surface without mulch “WM”). The following parameters were studied to evaluate the effect of pulse drip irrigation and mulching systems: 1) Soil moisture distribution in root zone, 2) Growth characters of soybean plant, 3) Yield of soybean, 4) Irrigation water use efficiency of soybean “IWUE soybean”, and 5) Oil content and oil yield, 6) Protein content and protein yield, 7) Economical parameter. According to the economical view and the results of statistical analysis for effect of pulse drip irrigation and mulching systems on yield, quality traits and IWUE soybean indicated that, applying the irrigation requirements on 8 pulses/day with using BPM is the best conditions because under these conditions was occurred the highest value of yield, quality traits and IWUE soybean and there was significant deference between this case and other treatments. Where, pulse irrigation technique increase from water movement in horizontal direction than vertical direction hence improve from soil moisture distribution and wetted soil volume in root zone and using BPM decrease from evaporation process rate from soil surface hence decreasing of salts accumulation in addition to decreasing of weed growth in the root zone. All traits at AIR on 12 pulses/ day are decreased by increasing of pulses, this may be due to irrigation water was very small with every pulse at AIR on 12 pulses/day in addition increasing the total time of time-off, this mean, un-sufficient application for irrigation water to remove water stress in the root zone.

Interaction of Carbon Dioxide Enrichment and Soil Moisture on Photosynthesis, Transpiration, and Water Use Efficiency of Soybean

Soybean (Glycine max (L.) Merrill) is one of the most important oil and protein sources in the world. Interactive effect of elevated carbon dioxide (CO2) and soil water availability potentially impact future food security of the world under climate change. A rhizotron growth chamber experiment was conducted to study soil moisture interactions with elevated CO2 on gaseous exchange parameters of soybean under two CO2 concentrations (380 and 800 μmol·mol-1) with three soil moisture levels. Elevated CO2 decreased photosynthetic rate (11.1% and 10.8%), stomatal conductance (40.5% and 36.0%), intercellular CO2 concentration (16.68% and 12.28%), relative intercellular CO2 concentration (17.4% and 11.2%), and transpiration rate (43.6% and 39%) at 42 and 47 DAP. This down-regulation of photosynthesis was probably caused by low leaf nitrogen content and decrease in uptake of nutrients due to decrease in stomatal conductance and transpiration rate. Water use efficiency (WUE) increased under elevated CO2 because increase in total dry weight of plant was greater than that of water use under high CO2 conditions. Plants under normal and high soil moisture levels had significantly higher photosynthetic rate (7% to 16%) favored by optimum soil moisture content and high specific water content of soybean plants. Total dry matter production was significantly high when plants grown under elevated CO2 with normal (74.3% to 137.3%) soil moisture level. Photosynthetic rate was significantly and positively correlated with leaf conductance and intercellular CO2 concentration but WUE was significantly negatively correlated with leaf conductance, intercellular CO2 concentration and transpiration rate. However, the effect of high CO2 on plants depends on availability of nutrients and soil moisture for positive feedback from CO2 enrichment.

玉米大豆间作干物质积累和氮磷吸收利用的边际效应

【目的】研究间作对玉米大豆干物质积累及氮磷吸收利用特性的影响机制,对实现玉米、大豆间作高产高效具有重要指导意义。【方法】试验设玉米单作、大豆单作、玉米大豆间作3种种植方式,分别测定玉米大口期、吐丝期和成熟期的植株氮磷积累量和大豆开花期、结荚期和成熟期的植株氮磷积累量,研究间作对玉米、大豆不同器官干物质积累及氮磷吸收积累特性,明确氮磷吸收利用的边际效应。【结果】与单作相比,间作降低了玉米干物质和氮磷的积累,促进了根系吸收氮向籽粒的分配;降低了大豆干物质积累,尤其对中行的影响大于边行,边行干物质、氮磷积累体现边际效应优势;与单作体系相比,间作使玉米大豆植株茎叶营养器官氮转移量均减少,分别降低22.13%、29.85%,转运氮对玉米籽粒氮的贡献率分别下降5.11%、17.45%,且根系吸收氮对籽粒氮的贡献率均高于转运氮对籽粒氮的贡献率。间作能够有效提高系统氮利用效率,较玉米、大豆单作分别提高2.34%、4.62倍,使系统氮效率较单作大豆提高26.82%,较单作玉米降低10.16%,玉米在系统产量中占主导地位,占系统产量的82.27%,土地当量比(LER)达到1.47,系统产量为13110 kg/hm^(2),较单作玉米下降3.96%。【结论】间作优势主要在于促进根系吸收氮向籽粒的分配,提高氮的利用效率。

Optimizing Nutrient Use Efficiency and Returns from Soybean Production under Smallholders in Three Agro-Ecologies of Malawi

Field trials were conducted to determine the economically optimum fertilizer rates for soybean production and for optimizing net profits in Dedza, Lilongwe and Salima Districts of Malawi. The effects of PK fertilizer rates on rain use efficiency (RUE), harvest index, agronomic use efficiency of phosphorous (AEP) and potassium (AEK), and value cost ratio (VCR) were evaluated. The applied diagnostic PK fertilizer rates significantly improved soybean grain yields, harvest index, rainwater use efficiency, AEP, AEK and returns to fertilizer use expressed as value cost ratio (VCR). However, the results differed significantly

减施氮肥和接种根瘤菌对大豆生理生长与氮素利用效率及产量的影响

在干旱、半干旱地区农业生产中,广泛采用接种根瘤菌、施用氮素等措施来促进大豆生长以提高产量,然而少有研究讨论接种根瘤菌与施用氮素的交互作用对大豆生长和产量的影响规律。本研究通过为期2年的田间试验,设置4个施氮水平(N0:0 kg/hm^(2);N1:60 kg/hm^(2);N2:120 kg/hm^(2);N3:180 kg/hm^(2))和2种接种水平,即接种根瘤菌(R)和清水拌种。在大豆各生育期测量根瘤数、根瘤干质量、叶面积指数、干物质积累及根系特性等大豆生长指标和叶绿素含量、光合参数、荧光参数等生理指标,同时还测定氮素吸收量等指标并计算氮素利用效率。结果表明,RN2处理下的大豆生长状况最佳,2年平均最大根瘤数为241.47、最大根瘤干质量为1.30 g、最大根长密度为15.00 cm/cm^(3)、最大叶面积指数为5.44 cm^(2)/cm^(2)、最大干物质积累量为17 530.51 kg/hm^(2)、最大叶绿素含量为53.55、最大净光合速率为32.75μmol/(m^(2)·s)、最大种子产量为4 659.4 kg/hm^(2)。由此可见减少氮肥施用量(N2)的同时接种根瘤菌(R)对于促进关中平原大豆的生理生长、提升对氮素的利用效率、提高大豆产量具有重要意义。本研究可为提高干旱半干旱地区大豆生产水平提供理论支持和实践经验。

加入WTO以来中美经贸关系演变下的大豆贸易研究

中美大豆贸易是中美经贸的重要组成部分。自中国加入WTO以来,中美大豆贸易深受中美经贸关系变动影响。中美经贸关系常态化下,中美大豆贸易依存度较高,中国市场对美国大豆出口的重要性和稳定性不断加强。中美经贸摩擦期间,双边大豆贸易对中美经贸摩擦紧张程度作出即时反应,一定程度上重塑了世界大豆贸易格局,但中美经贸摩擦并没有改变中美大豆贸易紧密关系。中美经贸关系止跌企稳后,新兴大豆生产国短期内仍无法撼动美国对中国进口大豆贸易的重要地位。长期来看,巴西、阿根廷与美国出口大豆将互补式满足中国大豆需求。据此,中国应维护好与美国、新兴大豆生产国的关系,减少地缘政治风险与基建落户对大豆贸易的影响;积极拓展与“一带一路”沿线国和自贸区国家的伙伴关系,鼓励具有国际经验的大中型企业“走出去”;完善大豆产业政策,引导和调动国内农民大豆种植积极性,增强国内大豆生产能力。

玉米大豆兼用腔盘组合孔式排种盘设计与充种性能试验

针对玉米大豆带状复合种植条件下传统机械式排种器不易实现二者兼用精量排种要求、现有气力式排种器排种速度提高因型孔漏充存在漏播断条等问题,设计了一种具有腔盘组合孔结构的排种盘,分析确定了排种盘关键结构参数,构建了吸附过程和吸运过程力学模型。应用EDEM离散元仿真与台架试验相结合的方法进行了排种盘型式优选试验,结果得出:腔盘组合孔式排种盘具有提高充种室种群定向运移平均速度和增大拖拽充种角的作用,有效抑制了型孔漏充率。以安装优选种盘的玉豆兼用排种器为对象,以机组前进速度和工作负压为试验因素,以漏充率和充种合格率为试验指标,采用二因素全因子试验设计开展了充种性能试验,结果表明:当机组前进速度为4.0~7.0 km/h、工作负压在3.0~4.0 kPa时,玉米和大豆种子漏充率均小于3.6%、充种合格率均不小于96%。田间验证试验表明,在机组前进速度为4.0~7.0 km/h、工作负压为3.0~4.0 kPa条件下,腔盘组合孔式排种盘的排种器播种玉米和大豆漏充率分别不大于3.8%、4.2%;当工作负压为3.0 kPa、机组前进速度为7.0 km/h时,自扰动腔盘组合孔式排种盘相比无扰动平面排种盘,播种玉米和大豆漏充率分别下降14.8、12.6个百分点。

Telecoupled land-use changes in distant countries

International food trade has become a key driving force of agricultural land-use changes in trading countries, which has influenced food production and the global environment. Researchers have studied agricultural land-use changes and related environmental issues across multi-trading countries together, but most studies rely on statistic data without spatial attributes. However, agricultural land-use changes are spatially heterogeneous. Uncovering spatial attributes can reveal more critical information that is of scientific significance and has policy implications for enhancing food security and protecting the environment. Based on an integrated framework of telecoupling （socioeconomic and environmental interactions over distances）, we studied spatial attributes of soybean land changes within and among trading countries at the same time. Three distant countries -- Brazil, China, and the United States -- constitute an excellent example of telecoupled systems through the process of soybean trade. Our results presented the spatial distribution of soybean land changes-- highlighting the hotspots of soybean gain and soybean loss, and indicated these changes were spatially clustered, different across multi-spatial scales, and varied among the trading countries. Assisted by the results, global challenges like food security and biodiversity loss within and among trading countries can be targeted and managed efficiently. Our work provides simul- taneously spatial information for understanding agricultural land-use changes caused by international food trade globally, highlights the needs of coordination among trading countries, and promotes global sustainability.

Effect of Ambient UV-B on Stomatal Density, Conductance and Isotope Discrimination in Four Field Grown Soybean [<i>Glycine max</i>(L.) Merr.] Isolines

An experiment was designed to test whether ambient levels of UV-B radiation affect stomatal development, decrease stomatal density, and lead to increased water-use efficiency (WUE). Soybean [Glycine max (L.) Merr.] isolines with different stomatal distribution and flavonol expression patterns were field grown under shelters that either transmitted or blocked solar UV-B. All isolines exposed to solar UV-B accumulated higher concentrations of UV-screening phenolic pigments but other responses were isoline dependent. Solar UV-B decreased stomatal density and conductance in isolines expressing a unique branched kaempferol triglycoside. Decreased stomatal density was associated with increased season-long WUE and decreased internal CO2 concentration of leaf (estimated by δ13C discrimination). We concluded that photomorphogenic responses to UV-B affected stomatal density and WUE in field grown soybean;but that the magnitude and direction of these response were associated with isogenic pleiotropic differences in stomatal distribution and pigment expression. UV-B radiation had no effect on biomass accumulation or yield in a cultivar expressing only trace levels of kaempferol suggesting that flavonol expression is not prerequisite to UV-B tolerance.

不同灌溉方式对大豆耗水和水分利用效率的影响

【目的】研究不同灌溉方式对大豆全生育期耗水量及水分利用效率的影响,为大豆节水栽培提供科学依据。【方法】于2021年在甘肃武威绿洲农业高效用水国家野外科学观测研究站开展试验,设置了膜下滴灌、无膜滴灌、覆膜畦灌和无膜畦灌4种灌溉方式,每块试验田中心布设一台波文比-能量平衡系统对大豆全生育期的水热通量进行连续定位观测,研究了不同灌溉方式对大豆的农田小气候,生长发育,耗水量(ET),产量以及水分利用效率(WUE)的影响。【结果】①覆膜对比无膜提高大豆净辐射(Rn)6.58 W/m2,同时滴灌对比畦灌提高土壤温度1.30℃。②覆膜和滴灌2种措施在不同程度上对大豆的生理指标产生影响。与无膜相比,覆膜显著提高叶面积指数(LAI)18.29%;但畦灌比滴灌LAI高5.45%。③覆膜和滴灌均可显著降低大豆全生育期ET,膜下滴灌对比其他3种处理全生育期ET最小,仅为378.92 mm。④4种灌溉方式下,环境因子和生物因子中与ET正相关性最显著的分别为Rn和LAI。⑤膜下滴灌比无膜滴灌、覆膜畦灌、无膜畦灌各增产18.07%、5.27%、11.17%。同种灌溉方式下覆膜使WUE平均显著提高25.93%;同种覆膜条件下滴灌使WUE平均显著提高34.62%,膜下滴灌的WUE比无膜滴灌、覆膜畦灌、无膜畦灌分别显著提高31.15%、42.86%、70.21%。【结论】膜下滴灌比无膜滴灌、覆膜畦灌、无膜畦灌的产量平均提高了11.51%,ET平均减少了24.13%,同时WUE平均提高了48.07%,灌溉水利用效率平均提高了46.57%;综合考虑作物的耗水、产量、WUE,膜下滴灌对大豆生长提供了更适宜的生长环境并具有明显的节水增产作用。

粮饲兼用大豆新品种东农饲豆1的培育及栽培技术

为适应畜牧企业需求,提高牛奶蛋白质含量,亟需选育饲用型或粮饲兼用型大豆新品种。东农饲豆1是东北农业大学2013年以黑龙江省主栽高产优质大豆品种合丰50为母本,以胰蛋白酶抑制剂缺失高世代品系HZ6009为父本进行有性杂交,经系谱法及胰蛋白酶抑制剂缺失检测分子辅助方法选育而成的产量及品质性状优异且Kunitz型胰蛋白酶抑制剂缺失的大豆新品种。该品种高油、高产,中抗灰斑病,适宜黑龙江省第二积温带≥10℃活动积温2400℃以上区域种植。该品种的育成满足了粮油、青贮、优质饲料等多种用途,应用前景广阔。2023年通过黑龙江省品种审定委员会审定,审编号为黑审豆2023Z0006。

灌溉模式对河西灌区禾-豆间作系统饲草产量、品质和水分利用的影响

2019-2020年,在甘肃河西地区设置玉米单作(C)、玉米-秣食豆间作(CM)和玉米-拉巴豆间作(CL)3个种植方式,每个种植方式设置重度亏水(T_(1))、后期亏水(T_(2))、交替亏水(T_(3))、后期轻度亏水(T_(4))、前期轻度亏水(T_(5))和充分灌溉(T6)6种灌溉模式,研究灌溉模式对禾-豆间作系统饲草产量、品质和水分利用的影响。结果表明,两年CM和CL处理的群体干草产量显著高于C,2019年较C分别增加6.48%和9.47%,2020年分别增加9.09%和13.11%。两年CM和CL处理的群体酸性洗涤纤维(ADF)和中性洗涤纤维(NDF)含量显著低于C,而群体粗蛋白含量、粗灰分含量及相对饲用价值(RFV)显著高于C,2019年CM和CL处理的RFV较C分别增加10.73%和13.06%,2020年分别增加7.39%和10.59%。两年CL处理的水分利用效率(WUE)和灌水相对生产效率(IPE)显著高于C,2019年较C分别增加7.77%和11.41%,2020年分别增加8.76%和15.11%。两年T_(5)、T6的群体干草产量无明显差异,而T_(5)处理的群体粗蛋白和粗脂肪含量较高,ADF和NDF含量较低,且T_(5)处理的WUE和IPE显著高于T6,2019年较T6分别提高22.14%和48.34%,2020年分别提高25.18%和45.51%。因此,玉米-拉巴豆间作(CL)在前期轻度亏水(T_(5))条件下能够提高群体饲草产量、品质和水分利用效率,是一种适宜河西灌区饲草作物高产优质栽培和水分高效利用的管理模式。

基于产量和水氮利用效率的玉米/大豆间作系统炭氮配施方案优选

【目的】实现间作系统低耗高效增产,获得适宜的炭氮配施方案。【方法】以间作玉米、大豆为试材进行田间小区试验,设置3个施炭水平:C0(0 t/hm^(2))、C1(15 t/hm^(2))、C2(30 t/hm^(2))和3个施氮水平:N1(135 kg/hm^(2))、N2(180 kg/hm^(2))、N3(225 kg/hm^(2)),并设置对照(CK,不施炭和氮),研究不同炭氮水平对玉米/大豆间作系统产量和水氮利用效率的影响,选用博弈论赋权的TOPSIS法进行综合评定,确定基于产量和水氮利用效率的最优配施方案。【结果】炭、氮及其交互作用对玉米和大豆的产量及水氮利用效率均有影响。其中C1N2处理的玉米产量和水分利用效率最高,C1N1处理的大豆产量、氮肥利用率、氮肥偏生产力和氮肥农学效率最高。通过解析炭氮调控模型得出,施炭和施氮协同影响综合评定值,随着施炭量和施氮量的增加,综合评定值先增加后降低,适宜生物炭减施氮肥对玉米/大豆间作系统产量及水氮利用效率具有正向耦合作用。【结论】推荐水肥相对充足的东北地区采用施炭量17.1~24.0 t/hm^(2)、施氮量154.8~173.7 kg/hm^(2)的配施方案。研究可为玉米/大豆间作系统“减氮增效”提供科学依据。

施肥方式对大豆不同生育期生长发育及产量的影响

为了探究氮、磷、钾肥、有机肥、生物菌肥的施肥策略对大豆生长发育及产量的影响,并为黄土旱区种植大豆选择适宜的肥料配比提供科学依据。试验以汾豆‘78’为研究对象,共设置CK(裸地;N,30 kg/hm~2)、A(膜际;N,30 kg/hm~2)、B(膜际;N,60 kg/hm~2;P_(2)O_(5),30 kg/hm~2;K_(2)O,30 kg/hm~2)、C(膜际;N,90 kg/hm~2;P_(2)O_(5),45 kg/hm~2;K_(2)O,30 kg/hm~2)、D(膜际;N,90 kg/hm~2;P_(2)O_(5),45 kg/hm~2;K_(2)O,30 kg/hm~2;优质营养土2.5 t/hm~2)、E(膜际;N,60 kg/hm~2;P_(2)O_(5),30 kg/hm~2;K_(2)O,30 kg/hm~2;微生物菌肥10 kg/hm~2)六个处理模式,采用随机区组设计,重复3次实验组,解析不同施肥策略对大豆的生长发育、产量及水分利用效率的影响。结果表明:(1)化肥配施有机肥能显著增加大豆的株高、茎粗,比对照CK分别增加了24.23%、21.20%;(2)增施N、P、K肥有利用大豆初期生物量的积累,后期有机肥的肥效开始呈现,成熟期增施有机肥效果最佳;(3)化肥配施有机肥、化肥配施生物菌肥有效促进大豆的光合速率和水分利用效率,光合速率比对照分别增加20.81%、19.91%,叶片水分利用效率比对照分别增加了20.18%、10.80%;(4)化肥合理配施有机肥显著提高大豆的产量,其产量达到了3 690.55 kg/hm~2,比对照增产53.29%。综上所述,化肥、有机肥和生物菌肥配施有利于促进大豆的生长发育和提高产量,而化肥配施有机肥为最佳的肥料配比方案。

不同肥水供给模式对高蛋白大豆干物质累积、氮素代谢、产量及品质的影响

为探索高蛋白大豆高产优质生产适宜肥水协同供给模式,以高蛋白驻豆19为试验材料,采用不同施氮量与灌水量进行田间裂区试验,设置3个施氮量水平,N0(不施氮肥)、N1(60 kg·hm^(-2))、N2(120 kg·hm^(-2));3个灌水水平,W0(不灌水,自然降雨)、W1灌水量(1500 m3·hm^(-2))、W2灌水量(3000 m3·hm^(-2)),研究了高蛋白大豆干物质和氮素累积与分配、氮素利用及品质对肥水协同供给的响应。结果表明:同一灌水量条件下,干物质积累分配量呈现豆荚>茎>叶,2020年豆荚分配占比53.65%~69.00%,2021年豆荚分配占比36.25%~52.15%;同一施氮条件下,随着灌水量的增加,鼓粒期干物质累积量呈逐渐升高趋势,在施氮N1条件下,灌水量为W2时,干物质累积量较自然降水W0、灌水量处理W1分别提高了56.55%和11.67%;不同灌水量条件下,提高施氮量反而降低了氮素吸收效率、氮素利用效率、氮肥农学效率、氮肥偏生产力,不同施氮量条件下,随灌水量的增加,氮素吸收效率、氮素利用效率、氮肥农学效率、氮肥偏生产力多呈增加趋势;同一灌水条件下,蛋白质含量不施氮最低,脂肪含量在施氮120 kg·hm^(-2)最低,不同灌水处理中W2N1产量最高达2319.86 kg·hm^(-2),显著高于其他两个灌水处理产量,处理间差异达显著水平。本研究为大豆高效节水节肥生产提供理论依据和技术支撑。

扁茎大豆材料的利用与新品种创新

为了改造与利用扁茎大豆材料,挖掘与转化有益基因,改良与创新品种,此研究以当地主要推广品种为核心亲本,扁茎大豆及其后代材料为改良亲本,连续进行杂交改良,充分利用杂交育种后代基因重组、累加与互补及突变等遗传效应,通过正确识别与确定扁茎大豆后代选择个体目标与连续定向选择,创新出合丰51、53号两个新品种和一批优良品系。概述了扁茎大豆材料改造与利用及创新品种的过程与试验结果,并就相关育种技术问题进行了讨论。结果表明,梯级杂交、定向选择与连续改良是改造扁茎大豆及其后代材料的有效方法。

大豆和小麦不同基因型的碳同位素分馏作用及水分利用效率

26个大豆基因型和 18个小麦基因型的叶片和种子的稳定碳同位素分馏值 (△ 13C)在正常供水和缺水的田间条件下皆有明显的基因型差别。土壤干旱降低△ 13C值 ,提高水分利用效率 ( WUE)并增大了不同基因型间的差值。抗旱性不同的基因型的叶片和种子的△ 13C平均值及相应的 WUE与抗旱性大小之间表现一定的规律性变化 ,抗旱性强的基因型的△ 13C比抗旱性中等和差者较低而相应的 WUE较高。叶片的△ 13C的基因型差异大于种子。结果表明 ,△ 13C受作物基因型控制和环境条件互作的影响 ,利用△ 13C评估和选育高 WUE种质应作干旱试验并计算△ 13C和 WUE的干

辽西半干旱地区深松中耕对作物产量的影响及其作用机理研究

对辽宁西部半干旱地区深松中耕对作物产量影响及作用机理的研究表明，深松打破了犁底层，减小了土壤容重及穿透阻力，增加了表层及亚表层土壤的孔隙度．深松土壤水分人渗可达８０ｃｍ，大豆根系深度增加３．６～４．０ｃｍ，大豆产量和水分利用效率分别增加２７．７～３４．５％和１６．１％，在干旱年份玉米增产７．９％．