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模拟犁底层条件下春玉米叶片形态发育及衰老表征 总被引：2，自引：0，他引：2
通过模拟犁底层和模拟打破犁底层处理进行试验,研究犁底层对春玉米叶片形态发育及衰老表征,明确犁地层对东北春玉米生产易引发早衰的机理。结果表明,模拟犁底层处理的第8片到第11片叶玉米叶片长度以及第13片叶到第20片叶叶片宽度均小于模拟打破犁底层处理,达到极显著水平;从5片叶全展开到小喇叭口期,模拟犁底层处理比模拟打破犁底层处理晚发育9 d;模拟犁底层处理缩短了中部叶片的持绿时间6 d;模拟犁底层处理相对模拟打破犁底层处理降低了开花期绿叶面积及开花后相对绿叶面积,生产上采用农业机械深松打破犁底层可延缓后期叶片衰老进程。 相似文献
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选用生育期相近的宏硕899、粒收1号、郑单958共3个品种,在3个种植密度下进行生理成熟期、收获期子粒含水率与植株叶片、茎秆、穗部、子粒脱水特性分析。结果表明,植株各部位含水率生理成熟期前后变化差异较大,生理成熟前2周,穗位茎、茎秆、穗柄、穗轴含水率几乎不变,穗位叶、苞叶、子粒含水率呈降低趋势,子粒含水率在30%～35%时苞叶与叶片进入迅速脱水期;生理成熟后穗位节茎秆含水率下降快于其他茎秆,茎秆与穗柄含水率下降速率相近,穗轴与子粒含水率下降幅度相近。品种间生理成熟时子粒含水率无显著差异,郑单958生理成熟后子粒脱水速率低于宏硕899和粒收1号。随密度增加,生理成熟期植株叶片、茎秆含水率呈降低趋势。密度对穗轴、穗柄及子粒含水率影响较小,不同密度处理间含水率无显著差异。辽东地区增加密度能够提高植株生理成熟后叶片、茎秆脱水速率,但对子粒含水率及脱水速率无显著影响,品种持绿性与子粒后期脱水相关性不大。受降雨影响辽东地区玉米生理成熟后空气相对湿度大,子粒脱水速率慢,降低收获时子粒含水量应从立秆延迟收获入手。 相似文献
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采用基因型×环境互作效应的加性-显性-母体遗传模型(ADM模型)分析方法,研究玉米叶片、子粒、茎秆、叶鞘、苞叶、穗轴等含水量遗传主效应及其与环境互作遗传效应。结果表明,子粒含水量同时受加性效应、显性效应、母体效应控制;叶片含水量同时受加性效应、显性效应遗传主效应控制;茎秆受显性效应遗传主效应控制。子粒、叶片、茎秆含水量等性状不同遗传控制体系受基因型×环境互作效应显著影响,对这些性状的选择效果受环境影响较大,宜在较晚世代进行选择。 相似文献
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玉米拔节后不同水分处理对植株性状和水分利用效率的影响 总被引：2，自引：2，他引：0
采用田间试验的方法,在不同灌水条件下,研究吉林省西部半干旱区春玉米植株性状、水分利用特性、茎秆强度与植株性状的关系。结果表明:随着灌水量的增加,玉米株高增加,穗位高和茎秆强度有所增加,对茎粗的影响相对较小。干旱胁迫下适度灌水,玉米的茎秆强度和株高、茎粗及穗位高呈正相关关系;在灌水量达田间持水量100%的处理下,玉米的茎秆强度和株高、茎粗及穗位高呈负相关,即玉米的茎秆强度随株高和穗位高的增加而呈降低趋势,从而增加了倒伏的风险。随着灌水量的增多,玉米产量提高不明显,水分利用效率显著降低。 相似文献
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干旱是作物生产的一个主要限制因子。研究作物对干旱胁迫反应的遗传因素,可以为改良作物的抗旱性提供可靠的理论依据。高粱对干旱有广泛的适应性，是禾本科作物中研究抗旱性的优良模式作物。高粱对干旱抗性分为开花前抗旱性和开花后抗旱性。花前干旱影响穗子大小、稳粒数及籽粒产量；花后干旱会造成叶片、植株的死亡，导致炭腐病和倒伏发生并影响籽粒的饱满度，二者均能造成严重的产量损失。持绿是高粱的一种抗旱机制，具持绿性状的基因型，在开花后遇水分胁迫时抗旱抗植株过早衰老，籽粒正常灌浆。采用不同遗传背景的重组近交系(RIL)群体和近等基因系(NIL)，并结合分子遗传学手段研究持绿数量性状位点(QTL)，发现了多个基因组区段控制对开花前和开花后水分胁迫的抗性，找到了多个在不同环境中持续表达的持绿QTL。持绿QTL的分子遗传分析为进一步理解高粱及其它禾本科作物抗旱性的生理机制奠定了基础。 相似文献
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干旱条件下我国不同年代玉米品种保绿性比较 总被引：1，自引：0，他引：1
选用35个玉米品种(农家种4个, 双交种4个, 单交种27个), 在海南三亚设置正常浇水和花期干旱两个处理, 鉴定每个品种在干旱环境下的保绿性, 比较不同年代品种的持绿性。结果发现, 干旱导致玉米叶片叶绿素含量下降, 衰老启动时间提前, 干旱条件下品种的衰老启动时间、最大衰老速度出现时间均随年代更替而延后, 最大衰老速度均随着年代更替而下降, 即玉米的保绿性均随着年代更替而提高, 与正常浇水条件下的趋势相似。玉米保绿性与叶绿素含量均与产量呈显著相关;在干旱处理条件下, 品种保绿性均随年代更替而提高, 我国的玉米育种中已经对持绿性进行了改良, 耐旱性也得到提高。 相似文献
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以免耕平作为对照,研究不同垄作覆盖模式对夏玉米耕层土壤含水量、干物质积累与分配以及产量的影响效应。结果表明,垄作和覆盖栽培的保水效果在玉米生育后期尤其是干旱时更为显著。相同条件下宽窄行垄作栽培处理的增产效果明显优于等行距垄作处理,无覆盖条件下等行距垄作处理的实际产量较平作处理提高0.5%,宽窄行垄作处理提高8.91%;覆盖条件下等行距垄作处理与宽窄行垄作处理的实际产量较平作处理分别提高3.62%和11.59%。相关及通径分析表明,子粒实际产量与开花至成熟期耕层土壤平均含水量、大喇叭口期叶片干重以及成熟期叶片干重呈显著正相关。提高开花至成熟期耕层土壤平均含水量、降低开花期茎鞘干重、促进叶片的干物质积累是垄作覆盖模式下玉米获得高子粒产量的主要原因。 相似文献
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E.J. van Oosterom S.C. Chapman A.K. Borrell I.J. Broad G.L. Hammer 《Field Crops Research》2010,115(1):29-38
Maintenance of green leaf area during grain filling can increase grain yield of sorghum grown under terminal water limitation. This ‘stay-green’ trait has been related to the nitrogen (N) supply–demand balance during grain filling. This study quantifies the N demand of grain and N translocation rates from leaves and stem and explores effects of genotype and N stress on onset and rate of leaf senescence during the grain filling period. Three hybrids differing in potential height were grown at three levels of N supply under well-watered conditions. Vertical profiles of biomass, leaf area, and N% of leaves, stem and grain were measured at regular intervals. Weekly SPAD chlorophyll readings on main shoot leaves were correlated with observed specific leaf nitrogen (SLN) to derive seasonal patterns of leaf N content. For all hybrids, individual grain N demand was sink determined and was initially met through N translocation from the stem and rachis. Only if this was insufficient did leaf N translocation occur. Maximum N translocation rates from leaves and stem were dependent on their N status. However, the supply of N at canopy scale was also related to the amount of leaf area senescing at any one time. This supply–demand framework for N dynamics explained effects of N stress and genotype on the onset and rate of leaf senescence. 相似文献
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大豆主要农艺性状的遗传解析 总被引：2，自引：0，他引：2
利用亲本冀豆12(高蛋白)和冀nf58(高油)及其175份F_(9∶11)重组自交系(RIL)材料,对大豆12个主要农艺性状进行了相关性和遗传分析,以期初步解析影响产量的主要因素。结果显示:亲本在株高、主茎节数、分枝数、百粒重、油分含量、蛋白含量和单株粒重7个性状上具有显著差异。在RIL群体中,12个农艺性状均表现为典型的数量性状特征,且具有相对较高的遗传率。其中,株高的遗传率最高(0.98),茎干重最低(0.63)。除3个性状(油分、蛋白含量和百粒重)外,其它9个性状之间呈现极显著的正相关,相关系数为0.30~0.90;蛋白含量与6个性状显著负相关,但与百粒重显著正相关。各性状与单株粒重相关性依次为:单株粒数单株荚数叶干重株高分枝数叶片数茎干重、主茎节数百粒重蛋白含量油分含量。选取19个单产最高的家系材料进一步分析表明,所测试的9个农艺性状主要遗传于母本冀豆12,而株高和主茎节数受到父本冀nf58的改良,说明通过聚合不同品种优异性状仍有提高品种产量的潜力。本研究结果可为培育高产优质大豆品种提供理论基础。 相似文献
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为给不同用途大麦高产、优质栽培适宜播期的确定提供参考,在大田条件下,以港啤1号、扬农啤2号、苏引麦3号、单2等4个大麦品种为材料,分析了播期对冬大麦开花期形态指标、产量和品质的影响以及形态指标与产量和品质的相关性。结果表明,随着播期的推迟,大麦产量、千粒重、开花期叶面积指数和干物重呈减少趋势,开花期单茎茎鞘重、籽粒蛋白质和淀粉含量呈增加趋势。产量在早播时与开花期单茎茎鞘重和叶面积指数正相关;适播时与开花期干物重和单茎茎鞘重正相关;迟播时与开花期单茎茎鞘重负相关,与叶面积指数正相关。千粒重早播时与开花期干物重和叶面积指数负相关,适播和迟播时与开花期单茎茎鞘重和叶面积指数负相关。籽粒蛋白质含量在早播和晚播时与开花期干物重和叶面积指数正相关;适播时与开花期单茎茎鞘重和叶面积指数正相关。各个播期下籽粒淀粉含量与开花期单茎茎鞘重和叶面积指数负相关。 相似文献
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播期和播量对滴灌冬小麦群体性状及产量的影响 总被引：4，自引：0，他引：4
为了给滴灌冬小麦种植选择适宜的播期和播量组合, 以两个冬小麦品种新冬22号和新冬27号为材料,设置2个播期（9月27日和10月7日）和3个播量（150、225和300 kg·hm-2）,通过大田裂区试验研究了播期和播量对滴灌冬小麦的群体性状、产量以及产量构成的影响。结果表明,冬前总茎数、返青后总茎数、成熟期收获穗数和主茎穗比重均随播量的增大而增加,且不同播量间差异显著;播期推迟,出苗数、冬前总茎数和返青后总茎数均降低。各处理均在孕穗期叶面积指数达到最大,且孕穗后10月7日播种的冬小麦叶面积指数下降比较慢。适当晚播有利于花后同化物和花前贮藏同化物在花后向籽粒的转运。播期和播量对滴灌冬小麦产量及其构成影响显著性,在10月7日播种、播种量为225 kg·hm-2处理下产量达到最高。 相似文献
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Improvements in dry matter digestibility of crop residues contribute to greater productivity of livestock consuming dual-purpose sorghums (Sorghum bicolor L. Moench). Delayed leaf senescence (stay-green), brown-midrib (bmr), leaf disease resistance, and high yield are among sorghum phenotypic traits that could enhance nutritive value of crop residues. The objective was to evaluate nutritive value and hydrocyanic acid potential (HCN-p) of leaf or stem components of crop residues of sorghum lines and hybrids representing differences in phenotypic traits. Four replications of eight or more lines and hybrids made up a randomized complete block design during 2 years in central Texas. Dry matter yield, dry weight loss after extraction in water and incubation in rumen, and fiber concentrations of leaves and stems were measured after grain harvest under field conditions. In addition, HCN-p of axillary branches and mature leaves was quantified. Sample weight loss in water extractions without incubation in rumen was negatively correlated with fiber concentrations, which were measured as the sample weights remaining after extraction in neutral (NDF) and acidic (ADF) detergent solutions. Greater concentrations of water-extractable dry matter and lower concentrations of NDF and ADF were observed for stay-green than for bmr or lines that senesced under drought. Yet, the sum of water-extractable dry matter plus ensuing weight loss during 7 days in rumen, expressed as yield ha−1 of leaf and stem digestible dry matter, was not consistently greater for stay-green than drought-susceptible lines. In addition, the yield of the sum of water-extractable and 7-day rumen losses of stay-green lines was comparable to or less than the bmr line. Under conditions in which leaf senescence varied little, analyses of nutritive value indicated water-extractable dry matter was enhanced and fiber concentrations were reduced in crop residues of stay-green compared to senescent lines. 相似文献
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保绿型玉米的营养生理研究进展 总被引：19，自引：2，他引：17
本文综述了近年来发展较快的保绿型玉米营养生理的研究进展,包括玉米保绿性的标准、玉米保绿性与植株含水量的关系、玉米保绿性与叶面积功能期的关系、保绿型玉米的营养生理基础及影响叶片保绿性的基因与环境因子等。 相似文献
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采用ADM遗传模型对不同玉米自交系开花后叶片保绿度衰减特性遗传效应进行研究。结果表明,不同自交系叶片保绿度衰减起始时间(Ts)、最大衰减速率出现时间(TVmax)、最大衰减速率(Vmax)均存在显著的遗传与环境互作效应,自交系叶片保绿度衰减特性在不同环境条件下的表现具有明显差异。利用包括基因型与环境互作效应在内的遗传分析方法,可以更清楚地发现不同亲本叶片保绿度衰减特性的遗传效应差异,有利于筛选出具有较大遗传效应的自交系,用于玉米叶片保绿度性状的改良。 相似文献
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ABSTRACTThis study identified timing (1st, 3rd, or 5th leaf stage) and duration (1, 3, 6, or 10 days) of waterlogging treatment during the vegetative stage that had the most severe effect on yield and elucidated yield determining process. Yield was reduced the most by the waterlogging treatments at the 3rd leaf stage. Among stages, yield was significantly depressed, when the treatment duration was longer than 6 days. Seed weight of the 1st branches declined more under waterlogging treatments than did that of main stem and 2nd branches, accounting for approximately 55% of total seed weight in all treatments. On the other hand, the decline in node and branch numbers was more pronounced for 2nd branches than 1st branches at the ripening stage. The development of the 2nd branches during ripening did not contribute much to increase sink capacity. Development of the main stem and the 1st branches was almost complete until the full flowering stage and shoot dry weight did not increase from the full flowering stage to the ripening stage. Shoot dry weight at the full flowering stage was determined by both leaf number and net assimilation rate (NAR). Flower cluster number at that stage was significantly correlated with total seed weight. These results showed that the critical timing was at the 3rd leaf stage and the critical duration was longer than 6 days and indicated that maintenance of leaf number and NAR and development of flowers on the 1st branches until the full flowering stage would ensure the yield.Abbreviations: NAR - net assimilation rate, SLA - specific leaf area, gs - stomatal conductance. 相似文献
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选用我国常用的82个不同基因型自交系为研究材料, 在两种氮肥处理下对其子粒产量、耐低氮指数、保绿性相关性状进行测定, 探究不同玉米自交系保绿性及其与氮效率的关系。结果表明, 以高氮下保绿度为指标筛选出了23个保绿型自交系, 27个早衰型自交系, 其余32个为中间型自交系。两种氮水平间保绿度及其相关性状差异均达极显著水平(P<0.01), 子粒产量与保绿度及其相关性状间的相关性均达极显著水平。研究表明, 保绿性不仅与子粒产量密切相关, 同时还显著影响氮效率。因此, 保绿性可作为筛选氮高效玉米自交系的一个重要农艺性状。 相似文献