四川盆地单产9000 kg hm~(-2)以上超高产小麦品种产量结构与干物质积累特点

选择3个典型超高产品种和7个一般高产品种(对照)在4个环境(年份×地点)下考察其产量、产量构成因素和干物质积累、转运特点,以揭示四川盆地高温、高湿、弱光照生态条件下超高产小麦品种的产量形成特性,为超高产育种和生产提供依据。超高产品种在4个环境下的平均产量达9338 kg hm 2,比对照品种高24.2%;其穗数(449×104hm–2)、穗粒数(42.3)、粒数(18 825 m–2)、千粒重(47.8 g)分别比对照高8.2%、10.7%、18.3%和0.6%。超高产品种在各个生育阶段的干物质积累速率、干物质积累量都高于对照品种,尤其是生育前期,如在分蘖盛期和拔节期干物质积累量分别高11.1%和18.2%;同时,其干物质转运量、转运效率和对籽粒的贡献率也高于对照品种,成熟时非籽粒器官干物质所占比重较对照品种低1.2~3.5个百分点。小麦籽粒产量与各个生育阶段的群体干重和分蘖、拔节期的个体干重呈极显著正相关,超高产品种具有分蘖力强,前期生长旺盛、干物质积累多,后期分配到籽粒的干物质比例较高等特点,这是高产的生理基础。

Yield Component and Dry Matter Accumulation in Wheat Varieties with 9000 kg ha−1 Yield Potential in Sichuan Basin

The objective of this study was to explore yield-forming characteristics of super-high-yield (SHY) wheat varieties that grow under high temperature, high humidity, and weak sunshine condition in Sichuan Basin, China. In four year ´ location environments, we tested the grain yield and its components of three SHY varieties and seven common high-yield varieties (control), as well as the characteristics of dry matter accumulation and translocation. The average yield of SHY varieties over environments reached 9338 kg ha^-1, which was 24.2% higher than that of the control. SHY varieties had average spike number of 449×10⁴ ha^-1, grain number per spike of 42.3, grain number of 18 825 m^-2, and thousand-grain weight of 47.8 g, which were 8.2%, 10.7%, 18.3%, and 0.6% higher than those of the control. At various growth stages, SHY varieties had significantly higher rates and larger amounts of dry matter accumulation, especially in the early growing period. For example, the amount of dry matter accumulation in the SHY varieties was 11.1% and 18.2% higher than that of the control at tillering and jointing stages, respectively. Moreover, compared with the control, SHY varieties had significantly higher amount of dry matter translocation, translocation efficiency, and contribution of remobilization to grain. At maturity, the proportion of dry matter in vegetative organs was 1.2%–3.5% lower in SHY variety than in the control. There were significant correlations between grain yield and colony dry matter at various growth stages and individual dry matter at tillering and jointing stages. SHY varieties tested in this study possess strong tillering ability, early vigorous growth, and high levels of dry matter accumulation and translocation into grains, which ultimately result in the high grain yield.