冬小麦品种籽粒平均灌浆速率的遗传机制研究

研究采用Griffing方法Ⅰ,利用6×6完全双列杂交,对6个冬小麦品种的籽粒平均灌浆速率的遗传机制进行了初步探讨.结果表明平均灌浆速率的一般配合力(GCA)效应、特殊配合力(SCA)效应和反交(R)效应均不同程度的达到显著和极显著水平,其均方比1.4268∶1.6839∶1;平均灌浆速率遗传以非加性基因效应占优势,加性基因效应次之;其广义遗传力为60.67%,狭义遗传力为78.69%.以综合性状评价河农2552品种为好.     

水氮耦合对冬小麦叶片叶绿素含量和光合速率的影响

于2006-2007年在大田条件下对灌水、施氮量和水氮互作对2个不同类型的冬小麦品种石新733和石麦15叶片叶绿素含量和光合速率的影响进行了研究.结果表明,适量施氮对提高小麦叶片叶绿素含量及光合速率效果明显.水氮耦合对叶绿素含量和光合速率具有类似的效应:灌拔节1水条件下,叶绿素含量及光合速率随施氮量的增高而增高;灌拔节、开花2水条件下;两品种旗叶叶绿素合成对施氮量需求呈现显著下降趋势,施氮量过高反而不利于叶绿素合成和光合速率的提高,石麦15表现更为明显;灌开花水可以延缓花后20 d后旗叶叶绿素的降解,但这一效应随着施氮量的增高而降低,石麦15表现尤其明显.叶绿素含量较低的品种石麦15在灌1水条件下叶绿素含量和光合速率在花后6～15 d呈显著正相关.石新733以春灌2水施纯氮240 kg/hm2,石麦15以春灌2水施纯氮120 kg/hm2叶绿素含量和光合速率最高.     

冬小麦-夏玉米复种连作中定位水氮组合对籽粒灌浆特性及产量的影响

为提高水氮高效利用,在2～3年定位水氮处理基础上于2008-2009年对玉米-小麦灌浆过程及产量形成进行了研究。结果表明,籽粒灌浆过程可较好的用Logistic函数描述。玉米粒重随施氮量增加呈抛物线变化,灌开花水高施氮量处理条件下粒重下降。小麦粒重随施氮量增加呈下降趋势,灌开花水显著提高粒重。灌浆持续时间和平均灌浆速率与粒重呈正相关,但灌浆持续时间和平均灌浆速率呈极显著负相关(R=-0.966 7)。玉米产量以1水条件下施氮480 kg/hm2最高,小麦产量以3水条件下施氮480 kg/hm2最高。     

水氮耦合对滴灌冬小麦光合特性、产量及水氮利用效率的影响

旨在明确水氮耦合对滴灌下超高产冬小麦光合特性和产量的影响。本研究采用裂区试验,研究了3种灌水量2775 m3/hm2(W1)、3900 m3/hm2(W2)、4350 m3/hm2(W3)水平与3 种施氮量0 kg/hm2(N0)、180 kg/hm2(N1)、270 kg/hm2(N2)水平对‘新冬41 号’旗叶叶绿素和可溶性蛋白质含量、光合速率、水分利用效率以及产量的影响。结果表明,水氮同时增加对花后旗叶叶绿素和可溶性蛋白含量、旗叶光合速率,水分利用效率和产量的提高比仅增加水或氮的作用更大,均以W2N2、W3N2处理花后旗叶叶绿素（分别较W1N0增加44.5%、41.2%）和可溶性蛋白含量（分别较W1N0增加20.8%、16.85%）、光合速率（分别较W1N0增加46.4%、54.5%）、水分利用效率（分别较W1N0 增加31.9%、34.7%）和产量（分别较W1N0 增加19.05%、20.86%）较高,W2N2、W3N2处理的旗叶光合性能大幅度提高是其产量较高的重要原因。综合水氮利用效率,W2N2(3900 m3/hm2、270 kg/hm2)是本试验条件下冬小麦产量近9000.0 kg/hm2的水氮高效运筹模式。     

不同栽培措施下冬小麦灌浆模拟研究

1994年在河北省衡水市邓庄中加合作试验站 ,结合田间试验对不同管理措施下冬小麦的灌浆过程进行了研究。结果表明 :粒重的大小主要取决于灌浆时间和灌浆强度 ,小麦子粒的灌浆过程可用Logistic函数描述。小麦生长前期的水分胁迫有利于加快其发育过程 ,促使早抽穗灌浆。灌浆期较好的水分状况可延缓小麦的灌浆进程 ,但较大灌浆速率持续的时间较长 ,千粒重的潜力值较大。小麦的群体密度是影响收获千粒重的主要因素之一 ,随着穗密度的增大 ,灌浆速率和千粒重逐渐降低。随着施N量的增加 ,小麦的千粒重降低 ,这主要与施N的增穗作用有关。     

灌浆斯冬小麦对干旱胁迫的某些生理生化响应

灌浆期冬小麦在干旱胁迫下,叶片中Ｐｒｏ含量增加,抗旱性弱的品种升市幅度大于抗旱性强的品种;可溶性蛋白质和可溶性糖下降,抗旱性强的品种下降幅度小于抗旱弱的品种。     

干旱胁迫对不同抗旱性冬小麦灌浆期下午旗叶光合特性和籽粒产量的影响

为了明确干旱胁迫对不同抗旱性冬小麦灌浆期下午旗叶光合荧光特性和产量的影响,2018—2019年度和2019—2020年度,在防雨棚池栽条件下,以强抗旱性冬小麦品种晋麦47（JM47）和弱抗旱性冬小麦品种偃展4110（YZ4110）为材料,采取测墒补灌的方法,设置重度干旱(W1:播前65%MFC（最大田间持水量）+拔节后45%～55%MFC)、中度干旱（W2:播前75%MFC+拔节后55%～65%MFC）、轻度干旱（W3:播前75%MFC+拔节后65%～75%MFC）、适宜供水（W4:播前75%MFC+拔节后75%～85%MFC）4个处理,测定了灌浆前期、中期和中后期14:00—16:00的旗叶净光合速率（Pn）、气孔导度（Gs）、胞间CO₂浓度（Ci）、蒸腾速率（Tr）、瞬时水分利用效率（IWUE）、PSⅡ最大光化学效率（Fv/Fm）、PSⅡ实际光化学效率（ΦPSⅡ）以及成熟期的产量及其构成因素。结果表明,水分和品种对小麦灌浆期下午的旗叶光合、荧光特性和成熟期的产量均有显著影响。从2 a均值来看,与W4相比,干旱胁迫处理（W1、W2和W3）灌浆期下午的旗叶Pn、G...     

华北平原冬小麦生长对水分胁迫的响应

通过对叶面积指数、生物量、水分利用效率、灌浆速率等数据的分析发现：拔节期胁迫对冬小麦的产量和水分利用效率有一定的影响；充分灌水处理生物产量较高但是水分利用效率低；不同生育期水分胁迫的处理对土壤储水量的消耗有明显的不同最大相差143．3mm；以棵间蒸发形式消耗的无效耗水也有明显的差异，最多相差20mm。     

春季追肥对冬小麦群体构建和籽粒灌浆进程的影响

为明确冬小麦春季合理追肥技术,以追肥时间（返青后10、25和40d）为主区,追肥量（90、120和150kg/hm²）为副区,研究春季追肥对冬小麦群体分蘖动态变化、籽粒灌浆进程、产量及氮效率的影响。结果表明,返青后25d较其他追肥时间显著提高了开花期分蘖数,追氮量为120kg/hm²时最高。返青后25d较其他追肥时间显著提高了籽粒灌浆起始势,籽粒达最大灌浆速率时间提高了1%~20%,提高灌浆过程中快增期和缓增期的灌浆速率,追氮量以120kg/hm²表现最好。返青后25d较其他追肥时间显著提高了成熟期植株干物质量及穗部结实性状,穗数、穗粒数、千粒重和产量分别提高8%~11%、7%~12%、3%~5%和8%~30%,且显著提高了氮肥偏生产力,以追氮量120kg/hm²最高。总之,返青后25d追肥可有效调控冬小麦春季分蘖消长,增加有效穗数,促进籽粒灌浆,提高粒重,且追施氮120kg/hm²实现了产量和氮效率同步提高。     

氮用量对大穗型小麦品种同化物供应及籽粒灌浆的影响

在大田条件下,研究了不同氮肥用量对豫麦66同化物供应及籽粒灌浆的影响。结果表明：增施氮素提高旗叶光合速率,尤其在灌浆中后期,同时增加籽粒WSC含量。随着施氮量增加,旗叶WSC含量在花后0~28d相对较低,旗叶淀粉含量降低,表明施氮能使营养物质及时外运,促进糖分向籽粒运输,为淀粉合成提供底物供应。在花后25d之后籽粒淀粉积累速率随施氮量增加而提高,尤其在接近成熟时籽粒淀粉含量及其淀粉积累速率均增加,显示施氮使库端利用和转化同化物的能力较强。籽粒淀粉积累速率与灌浆速率的变化均呈单峰曲线,两者呈显著正相关（r=0.844**）,增加施氮量两者积累高峰期推迟,且前期慢,后期快。     

Remobilization of Nitrogen and Carbohydrate from Stems of Bread Wheat in Response to Heat Stress during Grain Filling

When wheat (Triticum aestivum L.) is grown under heat-stress conditions during grain filling, preanthesis stored total non-structural carbohydrates (TNC) and nitrogen (N) could serve as alternative source of assimilates. This study was performed to evaluate wheat genotypes for their ability to accumulate and remobilize TNC and N stored in their stem to support grain filling under heat stress. Eighteen genotypes were used for N remobilization study while nine of them were used for TNC remobilization study. They were grown in pots and placed in a vinyl house with the maximum temperature kept below 30 °C. Five days after anthesis (5DAA), half of the pots were taken to phytotrons where temperature was gradually increased and the maximum was set at 38 °C. Grain yield and grain weight decreased by about 35 % under heat stress. Significant differences were found among genotypes in percentage reduction in grain yield, grain weight, grain filling duration and harvest index because of heat stress. The N and TNC concentrations of the stem at 5DAA were significantly different among genotypes. Heat stress significantly reduced the N remobilization efficiency of most of genotypes. However, heat stress significantly increased TNC remobilization efficiency and significant variation were observed among genotypes. N remobilization efficiency across treatments significantly correlated with grain yield, grain weight, harvest index and grain filling duration. TNC at 5DAA negatively correlated with N at 5DAA and harvest index, but the TNC remobilization efficiency under heat stress positively correlated with mainstem grain yield, grain weight and harvest index. The rate of chlorophyll loss from flag leaf positively correlated with N and TNC remobilization efficiencies under heat stress suggesting a link between leaf senescence and remobilization efficiency. The results indicate that heat stress negatively affected grain yield, its components and N remobilization while it increased TNC remobilization because of the increasing demand for resources.     

北方粳稻灌浆期水分胁迫条件下叶片内源激素变化的研究

为了阐明北方超级粳稻‘沈农265’的抗旱性生理机制,采用盆栽人工控制水分的方法,以北方超级粳稻‘沈农265’和米质优良的常规粳稻品种‘丰锦’为材料,在灌浆期进行不同程度的水分处理,比较两者生理反应上的差异。结果表明,与‘丰锦’相比,中度胁迫使‘沈农265’剑叶中叶绿素含量比‘丰锦’高5.03%,可溶性蛋白、可溶性糖含量及内源激素(IAA+GA3+ZR)/ABA比值分别比‘丰锦’低32.4%、11.41%和33.33%;重度胁迫下,‘沈农265’剑叶中叶绿素含量和可溶性蛋白分别比‘丰锦’高6.38%和20.2%,可溶性糖含量及(IAA+GA3+ZR)/ABA比值分别比‘丰锦’低51.5%和25%。上述结果说明,‘沈农265’具有较强的渗透调节能力,重度胁迫下,可溶性蛋白可能起主要作用;同时,‘沈农265’在相对高的(IAA+GA3+ZR)水平基础上增加ABA含量,不仅提高了干旱适应能力,也延缓了衰老,使其具有比丰锦更强的抗旱能力。     

氮素分期优化管理对冬小麦产量和籽粒品质的影响

采用田间试验,对氮素分期优化管理方法对小麦籽粒品质的影响进行了研究,以期为高产、优质、资源高效、环境保护等多重目标并重的养分资源优化管理提供理论依据.结果表明:氮素供应量最优的处理(冬小麦返青期氮素供应量即0～60 cm土壤Nmin+肥料氮为90 kg/hm2,拔节期追氮量即施用肥料氮30 kg/hm2)的冬小麦籽粒产量和其他氮素供应量处理没有显著差异;氮素供应量最优的处理冬小麦籽粒的粗蛋白和面筋含量显著低于在返青期和拔节期供氮量都高的处理(冬小麦返青期氮素供应量即0～60 cm土壤Nmin+肥料氮为150kg/hm2、拔节期追氮量即施用肥料氮90kg/hm2),但与其他处理相比差异不显著;以高产、资源高效和环境保护为前提的冬小麦氮肥分期优化施用量获得了最高产量的同时兼具较好的小麦籽粒品质.     

IAA和ABA对小麦籽粒灌浆过程的影响

采用3个粒重有较大差异但生育期基本相同的基因型,对它们籽粒发育过程中IAA和ABA水平的变化及其与充实速率的关系进行了研究。结果表明,IAA的含量和浓度与小麦籽粒的充实速率有显著的正相关;这种相关性不仅表现在籽粒的发育进程中,而且表现在基因型间充实速率的差异上。IAA含量较高的基因型,其充实速率也较高。ABA与小麦籽粒的充实速率也呈显著正相关,但在灌浆高峰期,当充实速率大幅度变化对,ABA却保持在一定的水平上。IAA和ABA在基因型间的差异主要表现在灌浆中后期。     

不同播期配合播量对冬小麦水氮利用及品质的影响

为了探寻协调产量和品质以及水氮利用的适宜播期及播量,在足墒播种+拔节期灌水75 mm的基础上,通过设置不同播期配合相应播量,研究不同处理对冬小麦产量、品质及水氮利用的影响。结果表明：10月10日播种(D-10)和15日(D-15)播种的小麦穗数、籽粒产量及地上部吸氮量都显著高于20日(D-20)和25日(D-25)播种;D-20、D-25处理的水分利用效率、氮素吸收效率和生产效率显著低于D-10、D-15处理。但是以适期晚播D-20处理的籽粒品质综合指标最优,过晚播种,尤其是早播不利于优良籽粒品质的形成。综合而言,以10月15日至20日作为当地常规年份节水小麦的适宜播期为宜,参考播量为225~262.5 kg/hm2。     

Winter Wheat Cultivar Responses to Fungicide Application are Affected by Nitrogen Fertilization Rate

Foliar fungicides are important management inputs for winter wheat (Triticum aestivum L.) in high-yielding areas of Europe, but their effectiveness may interact with cultivar selection and nitrogen (N) fertilization. No information is available on the potential use of fungicides in reducing yield losses from foliar diseases in Croatia, where wheat crop is extensively grown under low N inputs. Field experiments were conducted during 2000–02 to evaluate the agronomic responses of six winter wheat cultivars to fungicide application (tebuconazol around heading) compared with untreated plots at low (67 kg N ha⁻¹) and high (194 kg N ha⁻¹) N fertilization rates. Grain yields tended to increase in all years following fungicide treatment at high N rate by an average of 10.1 % (773 kg ha⁻¹), but improved significantly in one year only at low N rate. When these occurred, yield increases were associated with larger grain weight per ear primarily due to heavier 1000-kernel weight. Cultivars differed in their responses to fungicide application across growing seasons and N fertilization rates. Under low disease pressure in 2000 and 2001, improved yields with fungicide use occurred for few susceptible cultivars only, whereas all cultivars significantly increased yields under higher disease severity in 2002 by an average of 383 kg ha⁻¹ (5.0 %) at low N rate and 1443 kg ha⁻¹ (19.0 %) at high N rate. Following fungicide application at high N rate, some susceptible cultivars outyielded resistant cultivars, whereas opposite responses occurred in untreated plots. High N fertilization rate consistently produced larger grain yields except under high disease severity and no fungicide sprayed in 2002, when it had no benefits at all over low N rate. Fungicide application showed limited importance for wheat performance at low N rate; however, cultivars significantly differed in yield responses as well as in rankings after fungicide use at high N fertilization rate.     

不同播期对冬小麦粒重形成及产量的影响

以4个冬小麦品种为材料,研究了不同播期条件下籽粒灌浆特征参数、粒重和产量的差异。结果表明:播期对千粒重的影响存在差异,洛旱6号、洛麦21号和豫麦49不同播期之间的籽粒千粒重存在显著差异,但播期对偃展4110的千粒重影响不大。在不同播期下,灌浆过程中平均灌浆速率、快增期灌浆速率对粒重的影响较大。播期对不同品种灌浆高峰出现的日期影响基本一致,早播期>晚播期>中播期.但较早播种时,洛旱6号、洛麦21号和豫麦49灌浆高峰出现较早,灌浆速率大,晚播时偃展4110灌浆高峰出现较早,灌浆速率大。播期对4个品种产量的影响均以中播最高,在河南旱区生态条件下,似偃展4110的春性品种适宜播期为10月中下旬,洛旱6号、洛麦21号等似豫麦49的半冬性品种适宜播期为10月中旬。     

Evaluation of Grain Filling Rate and Duration in Bread and Durum Wheat, under Heat Stress after Anthesis

Bread and durum wheat genotypes were submitted to heat stress during the grain filling period, and relationships between grain weight and accumulated time from anthesis until maturity, using days after anthesis and growing degree days, were described by cubic polynomials. Maximum grain weight and the duration and rate of grain filling were estimated from the fitted curves. It was found that bread and durum wheat exposure to high temperatures significantly decreased grain weight and hastens physiological maturity (shortening the grain filling period). High temperatures significantly affected the rate (on a growing degree day basis) and duration (on Julian day units) of grain filling. The grain filling rate, on a thermal time basis, was positively associated with the final grain weight and the estimated maximum grain weight. The duration of grain filling does not appear to be a limiting factor for genotype grain weight stability, being mainly fixed by temperature. Grain weight of the controlled plants was positively correlated with the final and maximum grain weight of heat stressed plants. It was concluded that a high grain filling rate and a high potential grain weight are major traits that can be useful to improve heat tolerance of Triticum under Mediterranean environments.