小麦早熟高产品种光合生理特性分析

对陕西关中地区当前推广的早、中、晚三种熟性8个高产小麦品种的光合生理特性进行了研究，以探明参试的早熟小麦品种高产的光合生理机能和进一步提高早熟小麦品种产量潜力的性状改良途径，结果表明，参试早熟高产小麦品种的光合生理物性是：1．灌浆高峰期蒸腾速率高；2．花期至灌浆高峰期有持续稳定的高净光合速率；3．花前同化产物对子粒干物质累积贡献潜势大；4．花后单株生物增长量远高于中、晚熟品种；5．花前同化产物转流系数高，花后干特质增长系数高，光合产物分配性能好，收获指数高。同时也进一步明确早熟高产小麦品种的生物学产量低于中、晚熟品种，其原因主要在于拔节期至开花期的生物学增长量少。进一步提高早熟小麦品种产量潜力的途径是保持或提高收获指数的同时，较大幅度地提高花期的生物学产量。     

冬小麦粒充实度及灌浆模式的研究

通过对小麦子粒灌浆及发育的研究分析，提出了子粒充实度的概念及计算公式，并据此对河南省小麦子粒灌浆模式进行了研究，结果表明，品种间的子粒充实度存在着显著差异，它可以较好地反映子粒生长潜力的发挥程度。河南省的高产小麦品种可以划分为中种灌浆模式：－①高灌浆速度与短灌浆持续期相结合类型；②长灌浆持续期与早开花相结合类型；③长灌浆持续期与晚开花相结合类型；④低灌浆速度与长灌浆持续期相结合类型。其中，①②模式     

不同熟期类型玉米品种籽粒灌浆和脱水特性

根据自然生态条件及玉米品种的熟期、籽粒灌浆与脱水特性和产量潜力等进行科学品种布局,是实现玉米高产优质和资源高效利用的重要途径。本试验选用中早熟、中熟和中晚熟3个熟期类型,共13个玉米生产主栽品种,通过测定籽粒干物质积累和含水率的动态变化,研究并明确了不同熟期类型玉米品种的籽粒灌浆和脱水特性,旨在为生产品种布局提供参考和指导。试验结果表明:产量、籽粒灌浆和脱水特性在不同熟期类型和品种间均存在显著差异。产量表现为中晚熟(13,813.0 kg hm^–2)>中熟(12,970.4 kg hm^–2)>中早熟品种(10,729.0 kg hm^–2),中晚熟分别较中早熟和中熟品种增产28.7%和6.5%。平均灌浆速率表现为中早熟(0.034 g 100-grain^–1℃^–1)>中熟(0.031g 100-grain^–1℃^–1)>中晚熟品种(0.027 g 100-grain^–1℃^–1),生理成熟后的平均物理脱水速率表现为中熟(0.027%℃^–1 d–1)>中早熟(0.025%℃^–1 d–1)>中晚熟品种(0.018%℃^–1 d–1)。中早熟代表性品种京农科728的平均灌浆速率和生理成熟后的物理脱水速率。分别较3个熟期代表性品种郑单958、先玉335、农华101高38.5%和112.5%、28.6%和54.5%、28.6%和13.3%;中晚熟代表性品种京科968产量潜力最大(14,813.0 kg hm^–2),且平均灌浆速率和物理脱水速率分别较同熟期品种郑单958高7.7%和18.8%。产量与灌浆期天数、积温、平均灌浆速率和百粒重呈显著或极显著正相关,收获期籽粒含水率与灌浆期天数和积温显著正相关、与生理降水速率和物理脱水速率极显著负相关,生理降水速率和物理脱水速率与平均灌浆速率相关性不显著。综上,中早熟、中熟和中晚熟3个不同熟期类型及不同玉米品种的籽粒灌浆和脱水特性差异显著,生产中品种布局除考虑熟期外还需兼顾该特性,以更利于实现玉米高产优质和资源高效利用。     

冬小麦子粒充实度及灌浆模式的研究

通过对小麦子粒灌浆及发育的研究分析,提出了子粒充实度的概念及计算公式,并据此对河南省小麦子粒灌浆模式进行了研究,结果表明,品种间的子粒充实度存在着显著差异,它可以较好地反映子粒生长潜力的发挥程度。河南省的高产小麦品种可以划分为四种灌浆模式：①高灌浆速度与短灌浆持续期相结合类型;②长灌浆持续期与早开花相结合类型;③长灌浆持续期与晚开花相结合类型;④低灌浆速度与长灌浆持续期相结合类型。其中,①②模式类型比较适合河南省的生态条件,子粒充实度较高。子粒充实度与子粒灌浆持续期、子粒灌浆完成期、开花期、起始生长势等密切相关     

辽东南地区玉米品种灌浆与脱水特性研究

选用不同熟期玉米品种分析其产量、灌浆特性与籽粒含水量变化,结果表明:中晚熟品种产量(8 840.2kg/hm2)显著高于中早熟品种(7 656.9kg/hm2),中晚熟品种百粒重显著提高(38.0g);早熟品种丹8439、利民33灌浆启动快,后期灌浆速率下降迅速;中晚熟品种丹8662、丹8420、桥玉8生育后期灌浆速率下降缓慢,百粒重显著高于中早熟品种;灌浆持续期早熟品种丹8439、利民33为52,53d,丹8662、丹8420、桥玉8分别为64,63,63d;不同熟期品种最大灌浆速率(Rmax)在1.2~1.3g/d范围内,品种之间差异不显著。在生理成熟前,丹8439籽粒脱水速率最快,中晚熟品种较慢,生理成熟后各品种籽粒含水量下降程度相似,至10月26日观测结束时,中早熟品种丹8439、利民33籽粒含水量分别为20.4%、21.1%,中晚熟品种为20.4%~26.3%。由此得出,在辽东南地区中早熟品种后期籽粒脱水速率快,但花后灌浆持续期短,产量降低严重,不利于实现高产;中晚熟品种灌浆持续期长,但成熟时籽粒含水量高,不利于机收。选择立秆性能好的中晚熟品种并延迟收获,能够实现高产与机械粒收。     

早熟高产玉米单交种生育特性与产量构成的关系

早熟玉米单交种子粒产量低的主要原因是营养生长期短，形成的叶片少且面积小，光合产物供应不足，从而导致穗部性状的劣化和子粒产量的不稳定性。以早熟为前提子粒高产的育种途径，除配合力选育外，还可以通过提高叶片生长率来实现。通过试验研究提出，在高配合力前提下把具有潜在高灌浆速率的早熟自交系同一定的中晚熟自交系组配单交，不仅可使营养生长期显著延长，同化物供应改善，而且也可使灌浆期显著缩短，从而达到早熟高产的目的。     

wangwenpo@126.com

 通过对不同密度处理的小麦子粒生长过程的分析表明：小麦开花后子粒鲜重、体积均呈“低—高—低”的变化，鲜重的变化略滞后，开花后含水量则不断下降，下降速率最快时期与灌浆速率最高时基本吻合。用logistic方程拟合了不同密度小麦子粒灌浆过程，快增期的天数和灌浆速率比较稳定；缓增期天数和灌浆速率的变异系数较大。因此，在提高缓增期灌浆速率的基础上，延长灌浆缓增期是目前增加粒重的关键。     

小麦大粒品种源库特点及其与穗粒重关系的研究

以大粒小麦兰考86（79）、中粒小麦豫麦41号为材料，在河南生态条件下，研究了小麦大粒品种源库特点及其与穗粒重的关系。结果表明：小麦大粒品种灌浆期叶片叶绿素、总糖、全氮含量高，光合强度大，茎鞘中总糖、全氮含量高，但下降快，碳水化合物运输受阻，后期氮素相对缺乏；粒重增长快，子粒中蛋白质含量高，变化平衡，不受子粒积累碳水化合物的影响；后期灌浆不充分，子粒饱满度差，子粒中GA3/ABA与灌浆速度呈显著的正相关，而旗叶与子粒中GA3／ABA的相关性不显著。     

不同熟期夏玉米品种籽粒灌浆脱水特性和激素含量变化

本文旨在研究不同熟期夏玉米品种籽粒灌浆与脱水特性和内源激素含量与平衡的变化,以期为黄淮海夏玉米机械化收获籽粒和高产高效品种筛选提供理论依据。以早熟玉米品种登海518(DH518)、衡早8号(HZ8)和晚熟玉米品种郑单958(ZD958)、登海605(DH605)为试验材料,研究玉米籽粒形成过程中干物质积累、水分含量及内源激素含量变化。结果表明,早熟品种较晚熟品种灌浆期短,籽粒开始脱水早,脱水速率高,生理成熟期粒重低,产量低,但早熟品种中DH518的产量显著高于HZ8。不同熟期玉米品种籽粒内源激素含量及其变化模式不同,但同一激素含量随籽粒发育的变化趋势一致。两早熟品种籽粒的ABA含量高于两晚熟品种,尤其表现在灌浆中后期。各品种籽粒灌浆、脱水速率均与内源激素含量有关,两早熟品种的籽粒脱水速率与玉米素核苷(ZR)含量呈显著正相关。     

不同杂交稻品种(组合)灌浆特性研究

应用Richards模型研究了12个杂交稻品种（组合）的子粒灌浆过程。结果表明：B优827、宜香优2292和内香2550强、弱势粒灌浆高峰时间间隔较短，为明显的同步灌浆类型；其余组合强、弱势粒灌浆高峰时间间隔较长，为明显的异步灌浆型。     

Simultaneous selection for early maturity, increased grain yield and elevated grain protein content in spring wheat

High grain yield and grain protein content, and early maturity are important traits in global bread wheat ( Triticum aestivum L.)-breeding programmes. Improving these three traits simultaneously is difficult due to the negative association between grain yield and grain protein content and the positive association between maturity and grain yield. We investigated the genetic relationship between maturity, grain yield and grain protein content in a population of 130 early maturing spring wheat lines in a high latitude (52–53°N) wheat-growing region of Canada. Grain protein content exhibited negative genetic correlation with maturity (−0.87), grain fill duration (−0.78), grain fill rate (−0.49), grain yield (−0.93) and harvest index (−0.71). Grain yield exhibited positive genetic correlation with maturity (0.69), rate (0.78) and duration (0.49) of grain fill, and harvest index (0.55). Despite the positive association between maturity and grain yield, and negative association between grain yield and grain protein content, higher yielding lines with medium maturity and higher grain protein content were identified. Broad-sense heritabilities were low (<0.40) for rate and duration of grain fill, grain protein content, spike per m², grains per spike, harvest index and grain yield, and medium to high (>0.40) for grain weight, days to anthesis and maturity, and plant height. Selection for longer preanthesis and shorter grain fill periods may help circumvent the negative association between grain yield and grain protein content. Selection for shorter grain fill periods and higher grain fill rate may be a useful strategy for developing early maturing cultivars with acceptable grain yields in northern wheat-growing regions.     

Genetic analysis of flowering and maturity time in high latitude spring wheat

Due to the short growing season in the high northern latitudes, the development of early maturing spring wheat (Triticum aestivum L.) cultivars is important to avoid frost damage which can lower production and quality. We investigated earliness of flowering and maturity, and some associated agronomic traits, using a set of randomly selected high northern latitude adapted spring wheat cultivars (differing in maturity) and their F₁ and F₂ crosses made in a one-way diallel mating design. The parents, and their F₁ and F₂ crosses were evaluated under field conditions over 2 years. Anthesis and maturity times were controlled by both vernalization response and earliness per se genes, mainly acting additively. Non-additive genetic effects were more important in controlling grain fill duration, grain yield and plant height. Additive × additive epistatic effects were detected for all traits studied except time to anthesis. Segregation analyses of the F₂ populations for time to anthesis indicated the presence of different vernalization response genes. Molecular genetic analyses revealed the presence of Vrn-A1 and Vrn-B1 genes in the parental cultivars. Narrow-sense heritability was medium to high (60–86%) for anthesis and maturity times but low to medium (13–55%) for grain fill duration, plant height and grain yield. Selection for early flowering/maturity in early segregating generations would be expected to result in genetic improvement towards earliness in high latitude spring wheats. Incorporation of the vernalization responsive gene Vrn-B1 in combination with vernalization non-responsive gene Vrn-A1 into spring wheats would aid in the development of early maturing cultivars with high grain yield potential for the high latitude wheat growing regions of the northern hemisphere.     

肥密水平对‘宁冬11号’灌浆特性及籽粒产量的影响

为明确施氮量和种植密度对冬小麦灌浆期生理特性的影响,采用二因素裂区试验设计,对‘宁冬11号’冬小麦籽粒灌浆特性、粒重及产量进行了研究。结果表明：施氮量对灌浆持续期有明显影响,尤其N4处理(360 kg/hm²)灌浆持续期明显增加,但同时造成小麦晚熟;施氮量对产量影响显著,以N3 (270 kg/hm²)处理产量最高;对灌浆速率和粒重影响不明显。种植密度对灌浆持续期没有明显影响,但对灌浆速率、粒重和产量影响较大：低密度处理（450×104粒/hm²）,粒重最大,灌浆速率也较高,但产量较低;中密度处理（600×104粒/hm²）灌浆速度快,产量最高。综合来看,在宁夏引黄灌区,当播种密度为600×104粒/hm²、施氮量270 kg/hm²时对冬小麦灌浆最为有利,并且产量最高,可达到12178.36 kg/hm²。     

优良种质‘宁春48号’早熟特性分析

研究春小麦‘宁春48号’早熟特点,旨在为宁夏引黄灌区早熟高产春小麦新品种选育和‘宁春48号’优良种质的利用提供理论依据。选取当地主推中晚熟品种‘宁春4号’作为对照,对‘宁春48号’的生育进程、幼穗分化及籽粒灌浆特性进行研究。结果表明,‘宁春48号’较对照‘宁春4号’提前7天成熟,主要体现在分蘖—拔节期、孕穗—抽穗期阶段持续天数较短,抽穗开花后灌浆持续天数没有缩短;幼穗分化在单棱期、二棱期、小花原基形成期持续时间缩短,造成‘宁春48号’穗长较短、小穗数和穗粒数较少;与‘宁春4号’相比,‘宁春48号’起始灌浆较早,灌浆持续时间较长,但灌浆速率整体上低于对照‘宁春4号’。试验认为,‘宁春48号’作为亲本使用时,应选择早熟、大穗、穗粒数多、高灌浆速率的种质材料进行组配;选择过程中,在保证后代材料早熟性及灌浆持续时间长的前提下,选择大穗、穗粒数多、高灌浆速率的后代材料。     

不同类型超级小麦产量构成因素及籽粒产量的通径分析

以8个不同类型的超级小麦新品种（系）为材料,研究了不同土壤肥力条件下3种类型超级小麦的产量构成因素变化及其对籽粒产量的相关分析和通径分析。结果表明,在高肥地力下,大穗型品种和中间型品种的产量高于多穗型品种;而中、低肥力下,多穗型品种的产量又显著高于大穗型品种。在本试验条件下,大穗型和多穗型品种的穗数、     

宁夏不同基因型春小麦磷营养的差异

在不同施磷土壤条件下,研究了宁夏春小麦100个基因型的磷营养性状的差异。结果表明,在低磷条件下,小麦籽粒产量和生物学产量在基因型间存在极显著差异（P＜0.01),而在高磷条件下存在显著差异（P＜0.05)。不论施磷与否,茎叶和籽粒中含磷量以及磷吸收累积量、磷利用效率、磷肥利用率和施磷增产率等在基因型间均存在极显著     

Analysis of Wheat Cultivar Differences in Grain Yield, Grain Nitrogen Yield and Nitrogen Utilization Efficiency.

More detailed information on the causes of yield variability among wheat cultivars is needed to further increase wheat yield. Field studies were conducted in Northern Greece over the two cropping seasons of 1985—1986 and 1986—1987 to assess the effects of nitrogen fertilizer and application timing of the various component traits that determine grain yield, grain nitrogen yield and nitrogen utilization efficiency of two bread ( Triticum aestivum L.) and two durum ( Triticum durum Desf.) wheat cultivars, using yield and yield component analysis. Nitrogen at a rate of 150 kg ha^-1 was applied before planting or 100 N kg ha^-1 before planting and then 50 N kg ha^-1 top dressed at early boot stage. Nitrogen and cultivars affected all traits examined, while split nitrogen application affected only some of the traits. Grain yields in the most cases were correlated with number of grains per unit area and grain weight and grain nitrogen yields in all cases with grain number per unit area. The contribution of the number of grains per spike to total variation in grain yield among cultivars was almost consistent (37 to 55 %), while the contribution of grain weight was more significant (up to 55 %) in high yields (>6.500kg ha^-1) and number of spikes per unit area (>500). The number of grains per spike contributed from 60 to 83 % to the total variation in grain nitrogen per spike. Increased grain nitrogen concentration resulted in a reduction of its contribution in grain nitrogen yield variation. Nitrogen utilization efficiency was higher during grain filling than during vegetative biomass accumulation. The contribution of nitrogen harvest index to the variation of utilization efficiency for grain yield was higher in plants receiving nitrogen application.     

Genetic improvement trends in agronomic performances and end-use quality characteristics among hard red winter wheat cultivars in Nebraska

Evaluation of wheat cultivars from different eras allows breeders to determine changes in agronomic and end-use quality characteristics associated with grain yield and end-use quality improvement over time. The objective of this research was to examine the trends in agronomic and end-use quality characteristics of hard red winter wheat cultivars grown in Nebraska. Thirty historically important and popular hard red winter wheat cultivars introduced or released between 1874 and 2000 were evaluated at Lincoln, Mead and North Platte, Nebraska in 2002 and 2003. An alpha lattice design with 15 incomplete blocks of two plots and three replications was used at all locations. Agronomic (days to flowering, plant height, spike length, culm length, grain yield and yield components, and grain volume weight) and end-use quality (flour yield, SDS-sedimentation value, flour protein content, and mixograph time and tolerance) traits were measured in each environment. Highly significant differences were observed among environments, genotypes and their interactions for most agronomic and end-use quality characteristics. Unlike modern cultivars, older cultivars were low yielding, and less responsive to favorable environments for grain yield and yield components. Semidwarf cultivars were more stable for plant height than traditional medium to tall cultivars. All cultivars had high grain volume weight since it is part of the grading system and highly selected for in cultivar release. Modern cultivars were less stable than older cultivars for SDS-sedimentation and mixing tolerance. However, the stability of older cultivars was attributed to their having weak mixing tolerance and reduced SDS-sedimentation values. The reduced protein content of modern cultivars was offset by increased functionality, as measured by mixograph and SDS sedimentation. In conclusion, breeders have tailored agronomic and end-use quality traits essential for hard red winter wheat production and marketing in Nebraska.     

施氮量对小麦花后氮素分配及氮素利用的影响

为研究黄淮海麦区化肥投入不断增加,而产量却徘徊不前的问题,以当地主栽品种矮抗58和周麦22为材料,采用4个施氮水平（0、120、240、360kg/hm ²）和品种的二因素分析方法研究了施氮量对小麦植株地上部各器官氮素分配及氮素利用的影响。结果表明：开花期至成熟期小麦植株地上部各营养器官氮含量和氮素积累量均下降。施氮量对开花期和成熟期小麦植株地上部各器官氮含量的影响均达显著水平,增加氮肥能显著促进小麦营养器官氮素向子粒转运和花后氮同化。开花期周麦22叶片氮素转运量优于矮抗58。矮抗58和周麦22花后氮同化量均以施氮量360kg/hm ²最高,花前氮素积累转运量对子粒贡献率达60.25%~97.55%,子粒氮收获指数为59.82%~79.48%,随施氮量的增加而呈下降趋势。施氮量120kg/hm ²处理的氮素养分利用效率、农学利用效率及生产效率均最高。增施氮肥对小麦子粒产量有显著促进影响,矮抗58在施氮量为360kg/hm ²时有最大子粒产量,周麦22在施氮量为240kg/hm ²时有最大子粒产量。推荐矮抗58和周麦22在黄淮海麦区的施氮量为240~360kg/hm ²。     

氮肥运筹对弱筋小麦群体指标与产量和品质形成的影响

以弱筋小麦品种扬麦9号和宁麦9号为材，研究了不同施氮水平及基追比对群体指标、产量和品质的影响。结果表明，孕穗期叶面积指数（LAI）随施氮量的增加而提高；小麦籽粒产量及成熟期生物产量、花后干物质积累量与施氮量均呈二次曲线关系；籽粒蛋白质含量、湿面筋含量与施氮量呈极显著正相关。增加后期追氮比例及同比例2次追氮均提高了成熟期生物产量、花后干物质积累量、茎蘖成穗率、孕穗期LAI、籽粒产量、蛋白质含量和湿面筋含量。花后干物质积累量、成熟期生物产量、成穗数、茎蘖成穗率与产量呈显著或极显著正相关，拔节期、孕穗期、开花期和灌浆期LAI与产量呈显著或极显著二次曲线关系。弱筋小麦实现优质和产量7 000 kg hm^-2的氮肥运筹技术以施氮量200 kg hm^-2和基肥∶拔节肥∶孕穗肥为7∶2∶1，其高产优质协调的关键群体调控指标，最适LAI为6.9，花后干物质积累量和成熟期生物产量分别为5 300和16 500 kg hm^-2，成穗数为466×104 hm^-2，茎蘖成穗率为50%。