花生节水补充灌溉试验研究

通过在不同供水水平的节水补充灌溉条件下,对春播花生全生育期耗水量、产量、品质及土壤水分变化进行试验研究．结果表明：春播花生在开花期每亩补灌15m^3比对照增产明显,单株生长稳健,百果重、百仁率、饱果率最大。开花期、结荚期各补灌30m^3,表现出单株生长旺盛,总分枝和结实枝明显增加,但饱果率、出仁率最低,比对照显著减产。     

连续干旱复水对不同基因型玉米苗期根冠补偿能力的影响

为了探究调亏灌溉诱导作物补偿效应的机制,采用桶栽试验,以玉米杂交1代(F1)及其父母本为试验材料,分别设置充分供水和连续3次干旱复水2个处理,研究连续干旱复水对夏玉米苗期根冠关系及根冠补偿能力的影响。结果表明:连续干旱复水显著抑制了父本总生物量的积累,与正常供水(对照)相比降低19. 9%,但对F1和母本总生物量积累无显著影响;初次与第2次干旱复水后母本地上部干物质积累大于地下部,第3次干旱复水后干物质向地下部分配的比例增加; 3次干旱复水父本均表现为地下部干物质积累大于地上部; 3次干旱复水后父、母本根冠比较对照分别提高33. 2%,5. 8%,F1在3次干旱复水过程中根冠比均低于对照,第3次干旱复水后根冠比较对照降低7. 3%。3次干旱复水后,F1冠层生长补偿能力显著增加,根系生长补偿无显著变化,两亲本冠层与根系生长补偿能力同步显著降低。可见,对玉米杂交种而言,苗期进行连续多次干旱复水锻炼能促进其地上生长补偿,大田栽培中可利用此原理提高苗期夏玉米干物质积累,增强抗旱能力并提高水分利用效率。     

水分胁迫及复水条件下外源Ca2+对玉米幼苗根系水力导度及生长的影响

利用10%PEG-6000模拟–0.2 MPa的水分胁迫,研究了外源Ca²⁺(在1/2 Hoagland营养液中添加10 mmol L^-1 CaCl₂)对水分胁迫7 d后及复水2 d,玉米幼苗整株根系水力导度(Lp_r)、根系生长及叶水势(ψ_w)的影响。结果表明,正常水分条件下,外源Ca²⁺处理降低了Lp_r,但对叶水势无影响;水分胁迫条件下,外源Ca²⁺显著提高了Lp_r、叶水势,减缓了水分胁迫对植物的伤害;复水1 d,两种钙水平下Lp均无明显恢复,但Ca²⁺处理的Lp_r显著高于对照,而叶水势无显著差异且均能恢复至正常供水时的水平;复水2 d,Ca²⁺处理的Lp_r即能恢复至正常供水时的水平,对照仅恢复为正常供水时的59.06%。进一步用HgCl₂检测表明,正常水分条件下外源Ca²⁺对水通道蛋白(AQP)活性没有影响;而水分胁迫下,外源Ca²⁺提高了AQP活性,对照AQP活性下降,说明水分胁迫时外源Ca²⁺促进了水分跨膜途径运输;复水2 d,外源Ca²⁺处理AQP活性恢复至正常供水时的水平,对照AQP活性未能恢复。另外,外源Ca²⁺处理减缓了水分胁迫对植物生长发育的抑制作用,促进了复水时侧根发育,增加根系吸水面积,为植株迅速恢复供水提供了形态学基础,增加了复水后的补偿效应。     

植物生长促进剂对赣北移栽棉生长发育及产量的影响

【目的】明确叶面喷施6种植物生长促进剂对赣北移栽棉生长发育的影响,筛选出对棉花增产效果好的类型在赣北植棉区棉花生产上推广应用。【方法】在赣北育苗移栽植棉模式下,利用萘乙酸、赤霉素、细胞分裂素、芸苔素、复硝酚钠和胺鲜酯于棉花苗期(三叶期)、现蕾期、开花期和盛花期喷施,研究其对棉花生长发育的影响。【结果】细胞分裂素和复硝酚钠在棉花前中期对生长的促进作用明显,且复硝酚钠表现盛花结铃期成铃速度快;胺鲜酯对棉花生长的促进作用前后期保持较好的态势,单株叶面积系数、单株鲜物质质量和干物质质量均最大;芸苔素在棉花受到不良环境的伤害后可增强棉株的抗逆能力,明显提高铃重和产量;萘乙酸虽然对棉花前中期生长发育影响小,但最终增产效果还较好;赤霉素对棉花后期生长不利,棉花表现个体小、铃重略降低;芸苔素+胺鲜酯不及各自单用效果好。【结论】6种植物生长促进剂在赣北育苗移栽植棉模式下,于棉花苗期、现蕾期、开花期和盛花期叶面喷施,对棉花生长发育均有促进作用,可提高籽棉产量2.43%～10.04%,建议棉花苗期和蕾期叶面喷施细胞分裂素或复硝酚钠,花铃期叶面喷施芸苔素或胺鲜酯。     

成熟期控水对烤烟生长及产量的影响

成熟期是烤烟需水次临界期。为明确烤烟成熟期土壤水分对烟株生长及烟叶产量的影响,试验在烤烟成熟期进行土壤控水,研究烟株物质积累及烟叶产量的变化。结果表明：成熟期土壤长期干旱不利于烟叶生长,干旱后复水对烟叶生长无明显影响,且土壤水分对烤烟茎围和根系体积的影响均不显著;长期干旱不利于烤烟根、茎和叶等器官生物量提高,旱后增加复水量有利于根系生长;长期干旱显著降低烟株干物质积累,复水提高干物质积累量,但仍低于充分灌溉处理;长期干旱烟叶产量降低9.70%,旱后复水2次烟叶产量仅降低1.80%,且上中等烟叶比例比对照处理（相对土壤含水率70%~75%）提高2.88%,而单位面积产值仅减少1.09%。烤烟成熟期干旱胁迫后复水一定程度限制了烟株生长,但烟叶产量下降较少,上中等烟叶比重提高,单位面积产值略微降低。     

干旱胁迫对春大豆超氧化物歧化酶活性和丙二醛含量的影响

大豆是一种对水分最敏感的豆类作物,明确干旱对大豆叶片主要生理特性的影响,对于进行更好的水分管理具有重要的理论和实践意义。本试验选用耐旱型品种黑农44和敏感型品种黑农65为材料,测定了不同生育时期干旱及复水后大豆叶片SOD活性和MDA含量。结果表明：在干旱条件下,SOD活性随干旱程度增加呈先增加后降低的趋势,活性增加幅度花期>苗期>鼓粒期,且黑农44的SOD活性明显大于黑农65;MDA含量随干旱程度增加呈逐渐上升趋势,苗期>开花期>鼓粒期,且黑农44明显小于黑农65。复水后,SOD活性和MDA含量均逐渐降低;苗期干旱复水后MDA含量恢复较快,开花期干旱复水后恢复时间较长,鼓粒期干旱复水后不能恢复。     

等渗NaCl和PEG胁迫及复水处理对藜麦种子萌发及幼苗生长的影响

利用Na Cl和PEG溶液模拟盐胁迫和水分胁迫,比较等渗Na Cl和PEG胁迫下藜麦种子萌发、幼苗生长以及胁迫解除后幼苗生长状况的差异,探明渗透胁迫对藜麦种子萌发及幼苗生长的影响。研究结果表明:(1)在水势<-0.6MPa时,PEG对种子萌发的抑制作用大于Na Cl,而在-2.3MPa Na Cl与-1.0MPa PEG条件下种子均不能萌发;随着水势的降低,两种胁迫处理的种子初始萌发时间均逐渐推迟,并且在同一水势条件下,PEG胁迫的种子初始萌发时间较Na Cl处理时间延长。(2)Na Cl和PEG胁迫下幼苗根茎生长总体呈低浓度促进、高浓度抑制的趋势,但对不同生长指标影响存在差异。在≤-0.6MPa Na Cl和≤-0.8MPa PEG条件下根长较对照显著降低,而在不高于-1.4MPa Na Cl和-0.6MPa PEG时茎长显著降低;在不高于-1.4MPa Na Cl和-0.6MPa PEG时根、茎、苗鲜重均显著低于对照;在低于-1.8MPa Na Cl或-0.8MPa PEG时,藜麦幼苗不能存活。(3)Na Cl处理,根、茎、苗长分别在不低于-1.0、-1.4和-1.0MPa时复水后可恢复至对照水平,甚至高于对照;根、茎、苗重分别在不低于-1.0、-1.8和-1.4MPa时复水后可恢复对照水平,甚至高于对照。前期不同浓度的PEG处理,复水后根茎长度与鲜重均能恢复至对照水平,甚至高于对照。(4)高盐环境降低幼苗根长分配,提高茎长分配,复水后根长与根重分配比例都有所提高,表现出一定的补偿性;干旱胁迫的加剧增加幼苗根长和根生物量的分配,但对幼苗自身根茎生物量分配比例影响不显著。说明藜麦具有很强的耐盐、耐旱及抗环境变化能力,适合在黄土高原引种。     

开花期干旱胁迫对鲜食糯玉米产量和品质的影响

为探明开花期(抽雄吐丝期)干旱胁迫对鲜食糯玉米(吐丝后23 d采收)产量和品质的影响, 以苏玉糯5号和渝糯7号为试材, 采用负水头供水控水盆栽装置控制土壤含水量, 设置开花期正常供水(土壤相对含水量80%)和干旱胁迫(土壤相对含水量60%) 2个处理, 研究干旱胁迫对鲜食糯玉米产量(鲜果穗和鲜籽粒)、籽粒组分、糊化和热力学特性的影响。结果表明, 开花期干旱胁迫减少籽粒数量、降低籽粒重量、缩小籽粒体积, 导致鲜果穗和鲜籽粒产量损失。开花期干旱胁迫下鲜食期籽粒淀粉含量升高, 但对于蛋白质含量渝糯7号降低, 苏玉糯5号变化不显著。蛋白质组分中, 对球蛋白含量影响不显著, 清蛋白、谷蛋白和醇溶蛋白均显著降低。开花期干旱胁迫显著降低淀粉粒平均粒径。碘结合力2015年度显著下降, 2014年度受干旱影响不显著。开花期干旱胁迫下籽粒峰值黏度、谷值黏度和终值黏度在苏玉糯5号中降低, 在渝糯7号中升高。开花期干旱胁迫下两品种峰值温度降低, 回生热焓值和回生值升高, 而热焓值仅渝糯7号在2014年度升高。总之, 开花期干旱降低糯玉米鲜果穗和鲜籽粒产量, 增加籽粒淀粉含量, 降低籽粒蛋白质含量、淀粉粒径和支链淀粉中长链比例, 进而使籽粒回生增加, 但糊化黏度两品种表现不同(渝糯7号升高, 苏玉糯5号下降)。     

新疆滴灌棉花花铃期干旱复水对叶片光合特性及产量的影响

在新疆气候生态条件下, 采用膜下滴灌植棉技术, 控制花铃期0~60 cm土壤滴水下限分别为田间持水量的45%(中度干旱)、60%(轻度干旱)和75%(正常供水, 对照), 滴水上限均为田间持水量, 研究不同程度干旱复水对棉花叶片光合特性及产量形成的影响。结果表明, 干旱降低了叶片净光合速率(P_n)和气孔导度(G_s), 中度干旱下叶片光化学猝灭系数(qP)、PSⅡ电子传递量子产量(Ф_PSⅡ)降低, 非光化学猝灭系数(NPQ)升高。复水后3 d内P_n和G_s恢复, 以轻度干旱恢复最快; Ф_PSⅡ和qP与Pn的变化相似; NPQ复水后1~2 d显著降低。从初花期至盛铃前期, 轻度干旱复水后光合物质累积量与对照无明显差异, 盛铃后期至吐絮期低于对照, 籽棉产量较低; 中度干旱复水后光合物质累积量及籽棉产量均最低。     

水分胁迫效应对冬小麦生长发育的影响研究

利用温室管栽试验，研究水分胁迫效应对冬小麦生长发育的影响。结果表明：苗期水分胁迫，拔节期与开花期复水能激发冬小麦根、茎、叶、冠生物量显著增长，三叶至分蘖期控水的处理绿叶面积日增量最大；前期一直干旱灌浆期复水能明显减缓植株的衰老速率。冬小麦前期经受中度或重度水分胁迫，拔节期复水后增产效果最大，前期经受中度水分胁迫，开花期复水后水分利用效率最高。确定土壤含水量占田间持水量55％为冬小麦分蘖期水分胁迫效应增产节水的水分临界指标。     

玉米花期干旱及复水对植株补偿生长及产量的影响

研究了花期干旱对盆栽玉米生长发育、生理特性和产量的影响及复水后植株的补偿生长。花期干旱使雌穗生长发育不良，产量下降，复水后被干旱所延迟的雌穗发育可以部分恢复，存在关明显的补偿生长。复水后产量的补偿表现为百粒重的增加，但这种补偿不足以弥补由于穗粒数的减少而导致的产量下降。随胁迫时间延长及胁迫强度的增加，叶片气孔阻力迅速增加，复水后气孔阻力迅速减少，胁迫强度愈大，恢复速率愈快、蒸腾速率与气孔阻力基本上     

土壤水分胁迫对冬小麦生长的后效影响

为揭示土壤水分胁迫对冬小麦生长的后效影响及其规律,利用盆栽试验对供试冬小麦设置13种供水处理,测定作物株高、叶面积、冠干重及产量,研究水分胁迫对上述生理指标的后效影响。结果表明,中度水分胁迫对株高的后效影响大于重度水分胁迫,在重度水分胁迫下,除C5-A外,当前影响均大于后效影响;前期中度水分胁迫对叶面积的后效影响大于当前影响,后期则相反,重度水分胁迫对叶面积的当前影响大于后效影响;水分胁迫对冠重的后效影响大于当前影响;水分胁迫对冬小麦穗数的后效影响基本上表现为正效应,而对每穗粒数、千粒重、产量及WUE的后效影响则全部为负效应,拔节至孕穗阶段中度水分胁迫抽穗期复水的处理产量最高,达到对照的62%。不同程度、不同历时、不同生育阶段的水分胁迫,对作物生长均有后效应,并导致小麦减产。     

Photosynthesis and Remobilization of Dry Matter in Wheat as Affected by Progressive Drought Stress at Stem Elongation Stage

With increasingly erratic rainfall patterns particularly in drought‐prone production systems, the capacity of plants to recover productively from drought spells becomes an important feature for yield stability in rainfed agriculture. Consequently, effects of water management at the stem elongation stage on partitioning and remobilization of dry matter, alteration in photosynthesis and water‐use efficiency (WUE), and yield components of wheat plants were studied in a glasshouse pot experiment. The plants were subjected to three soil moisture regimes: well watered during all phenological stages (WW), drought affected during stem elongation and post‐anthesis stages (DD) and drought affected during stem elongation and rewatered at post‐anthesis stage (DW). Total dry weight substantially decreased by both drought treatments. However, DD plants allocated relatively higher assimilates to roots whereas DW plants remobilized them to the grains. Drought applications resulted in a decrease of grain yield and thousand grain weight while reduction was more pronounced in DD treatment. Relative contribution of post‐anthesis photosynthesis to dry matter formation in grain was higher in WW treatment (72.6 %) than DD (68.5 %) and DW (68.2 %) treatments. Photosynthetic rate, gas exchange and transpiration decreased whereas leaf (photosynthetic) and plant level WUE increased with drought applications. However, all these parameters were rapidly and completely reversed by rewatering. Our findings showed that partitioning of dry weight to grain increases with rewatering of wheat plants subjected to drought during stem elongation phase, but the relative contributions of remobilization of stem reserves and post‐anthesis photosynthesis to grain did not change. Moreover, rewatering of plants at booting stage after a drought period lead to full recovery in photosynthesis and WUE, and a significant although partial recovery of yield components, such as grain yield, TGW and harvest index.     

水分胁迫对玉米生长发育及产量形成的影响研究

采用人工控制水分的方法,研究玉米生长发育和产量形成对水分胁迫的响应。研究结果表明：干旱胁迫导致玉米生长发育缓慢和减产程度的大小,因胁迫时期、胁迫程度及持续时间而不同。干旱胁迫对株高的抑制作用：拔节孕穗期>抽雄吐丝期>苗期,其中苗期株高在复水后得到了超补偿。受水分胁迫影响穗重、穗粒重和穗粒数都呈减少的趋势,变化幅度为穗粒数>穗重>穗粒重,不同生育期干旱胁迫处理的减产幅度为抽雄吐丝期>拔节孕穗期>苗期。苗期、拔节孕穗期和抽穗开花期减产程度分别达到30%、70%和90%以上。     

华北冬小麦开花期补灌的增产效应及其影响因素

为阐明华北地区冬小麦开花期补灌增产效应及其影响因素,制定稳产节灌制度,于2007—2016连续10年进行了大田定位试验,研究在冬小麦拔节期灌水基础上,播前底墒、长期不同施氮及生育期降水等对开花期补灌增产效应及水分利用的影响。裂区设计,灌水量为主区,设春灌1次水(拔节期75mm,W1)和2次水(拔节期和开花期各75mm, W2) 2个处理;施氮量为副区,设6个水平,分别为0 (N0)、60 (N60)、120 (N120)、180 (N180)、240 (N240)、300 kg hm-2 (N300)。冬小麦开花期补灌增产效应受播前底墒影响显著,播前2 m土体贮水量越大开花期补灌增产率越小。施氮水平也显著影响开花期补灌增产效应,随着定位试验年限的增加,N0和N60处理土壤有机质和全氮含量逐年下降,从第6年开始开花期补灌的增产效应基本丧失。在足墒播种和正常供氮(施氮量不低于120kghm-2)条件下,开花期补灌的增产效应还受冬小麦生育期有效降水量的影响,尤其是拔节–开花期的有效降水量。开花期补灌增产率随生育期以及开花后的有效降水量的增加而降低。拔节–开花期有效降水量大于25.3 mm时,开花期补灌没有显著优化穗数、穗粒数、千粒重、生物量、收获指数等产量性状,最终增产不显著;此情景下,拔节期灌1次水(75 mm左右),即可在维持较高产量的前提下,降低耗水、提高水分利用效率,实现稳产与节水协同。本研究表明,华北平原冬小麦在足墒播种、施氮量不低于120 kg hm-2、拔节期灌水前提下,拔节–开花期有效降水量可作为开花期灌水与否的重要决策依据。     

Traits in Spring Wheat Cultivars Associated with Yield Loss Caused by a Heat Stress Episode after Anthesis

Heat stress resulting from climate change and more frequent weather extremes is expected to negatively affect wheat yield. We evaluated the response of different spring wheat cultivars to a post‐anthesis high temperature episode and studied the relationship between different traits associated with heat tolerance. Fifteen spring wheat (Triticum aestivum L.) cultivars were grown in pots under semifield conditions, and heat stress (35/26 °C) and control treatments (20/12 °C) were applied in growth chambers for 5 days starting 14 days after flowering. The heat stress treatment reduced final yield in all cultivars. Significant variation was observed among cultivars in the reduction in average grain weight and grain dry matter yield under heat stress (up to 36 % and 45 %, respectively). The duration of the grain‐filling period was reduced by 3–12 days by the heat treatment. The reduction in the grain‐filling period was negatively correlated with grain nitrogen yield (r = ?0.60). A positive correlation (r = 0.73) was found between the treatment effect on green leaf area (GLA) and the reduction in yield resulting from heat stress. The amount of stem water‐soluble carbohydrates (WSC) was not related to treatment effects on grain yield or grain weight. However, the treatment effect on stem WSC remobilization was negatively correlated with reduction in grain‐filling duration due to heat stress (r = ?0.74) and positively with treatment effect on grain N yield (r = 0.52). The results suggest that the effect of the heat treatment on GLA was the trait most associated with yield reduction in all cultivars. These findings suggest the importance of ‘stay green’‐associated traits in plant breeding as well as the need for better modelling of GLA in crop models, especially with respect to brief heat episodes during grain filling. There is in particular a need to model how heat and other stresses, including interacting effects of heat and drought, affect duration of GLA after flowering and how this affects source–sink relations during grain filling.     

播种前土壤喷施赛土丰对冬小麦农艺性状及产量的影响

研究旨在探讨小麦播种前土壤喷施微生物复合营养剂‘赛土丰’对小麦植株生长和产量提高的调控效应，以期为促进植株生长发育、提高产量调控技术的研究提供参考。试验于2016—2017 年进行田间试验，试验品种‘郑麦379’，设置空白不施肥（处理1）、清水（处理2，常规施肥）、‘赛土丰’复合营养剂（处理3，常规施肥），于生长期调查株高、次生根、叶色、病虫害等农艺性状指标，于成熟期考察其产量及产量构成因素各指标。结果表明：在小麦播种前土壤喷施‘赛土丰’微生物复合营养剂对小麦植株茎高、病虫害防御起一定的积极作用，尤其对小麦植株根的发育作用效果甚大。通过对产量及产量构成因素进一步分析发现，与处理2 叶面喷施清水相比，两试验地的喷施‘赛土丰’处理3 在成穗数、穗粒数上有所提高，但幅度不明显，然而在千粒重和产量上分别提高了13.09%、12.44%和4.67%、4.64%，提高幅度较为明显。综上说明，在冬小麦播种前土壤喷施‘赛土丰’微生物复合营养剂主要是通过提高小麦粒重来提高产量，且效果显著。     

Canopy Development and Light Absorption of Grain Legume Species in a Short Season Mediterranean-type Environment

Leaf area index (LAI), fractional canopy light interception (F) and plant mortality at maturity, were determined for nine short-duration pigeonpea ( Cajanus cajan [L.] Millsp.) genotypes in response to drought during the late-vegetative and flowering (stress 1), the flowering and early podfill (stress 2), or podfill (stress 3) stages. LAI and F were reduced, but plant mortality did not increase under drought. Stress 2 reduced LAI to the greatest extent, consistent with the effects on seed yield. At the end of stress 1, seed yield was closely related to LAI for the different genotypes in stressed but not in unstressed (control) plots. Reductions in LAI due to reproductive growth were as great or greater than those due to water stress. Indeterminate genotypes had smaller but more leaves per plant compared to the determinate genotypes. The importance of these differences to drought resistance was not apparent. Production of leaves with decreasing specific leaf area throughout plant growth may be advantageous, especially when drought is likely to occur during reproductive growth. Values of F during and following water stress gave an indication of genotypic drought resistance, with the most drought-sensitive genotype showing the largest reduction in F under water stress and the slowest rate of recovery following rewatering. For short-duration pigeonpea, where plant mortality is not a factor under water stress, the maintenance of both LAI and F appears to indicate genotypic drought resistance.     

小麦开花后根系衰退及分布规律的初步研究

在根系地下观测室的根系生长观测箱中,对小麦根系的立体分布和开花后的衰退规律进行了观察研究。结果表明,在开花期根系生长量达到高峰后,呈直线下降趋势;开花后根系在不同层次土壤同分布主要在６０－１２０ｃｍ;根系的衰退区主要在３０－６０ｃｍ,５月１１日－２１日衰退速度最快。