四川盆地小麦籽粒的灌浆特性

四川盆地小麦灌浆期长，粒重优势明显，但易受环境影响。2010-2011和2011-2012年连续2个小麦生长季，选用10个品种在3个地点进行灌浆特性研究，以揭示该区域小麦灌浆参数的基因型差异及环境效应。2年平均粒重48.25 g，灌浆分为渐增期(T₁)、快增期(T₂)和缓增期(T₃) 3个阶段，各阶段持续时间为T₃ (16.30 d)>T₁ (13.41 d)>T₂ (12.98 d)，其灌浆速率分别为0.618、0.772和2.205 mg grain^-1 d^-1。3个阶段的干物质积累贡献率依次为21.21% (T₁)、58.27% (T₂)和20.53% (T₃)，可见快增期结束时可以积累80%左右的干物质量。基因型、地点和年份对除粒重以外的所有灌浆参数均有显著影响，以年份的效应最大。同一年中，粒重、最大灌浆速率、平均灌浆速率、缓增期灌浆速率、渐增期灌浆速率和快增期灌浆速率主要受基因型的影响，而其他参数则以地点效应大于基因型效应。粒重与平均灌浆速率、最大灌浆速率、快增期灌浆速率和缓增期灌浆速率呈极显著正相关。10个参试品种中，川麦42、川育23和川麦56具开花期早、灌浆速率高、灌浆时间长、粒重大等特征。

Characteristics of Grain Filling in Wheat Growing in Sichuan Basin

The growing condition for winter wheat is relatively unfavourable in Sichuan Basin due to less radiation in wheat growing season, drought stress at mid growing stage, and high temperature at late growing stage. Wheat cultivars in this area are commonly characterized with large grain weight and long filling period. Therefore, quality of grain filling is critical to final yield. The objective of this study was to understand the effects of genotype and environment on characteristics of grain filling of wheat in Sichuan Basin. Ten representative cultivars were grown in three locations in 2010–2011 and 2011–2012 wheat growing seasons, and the dynamics of grain filling were observed. The average grain weight was 48.25 g over two years. There were three phases during grain filling, namely grain-filling pyramid period (T₁), grain-filling fast increase period (T₂), and grain-filling slowly increase period (T₃). The durations were sequenced as T₃ (16.30 d) > T₁ (13.41 d) > T₂ (12.98 d), and the grain-filling rates were 0.618, 0.772, and 2.205 mg grain^-1 d^-1, respectively. The contributions of biomass to grain were 21.21% in T₁, 58.27% in T₂, and 20.53% in T₃. Clearly, about 80% of dry matter has been accumulated before T₃ phase. In the same growing season, grain weight and grain-filling rates including maximum, (R_max),mean (R_mean), and phase (R₁, R₂, and R₃) rates of grain filling were mainly influenced by genotype, whereas other parameters for grain filling were mainly influenced by location. Grain weight was significantly correlated with R_mean, R_max, R₂, and R₃. Chuanmai 42, Chuanyu 23, and Chuanmai 56 were characterized with early anthesis, high grain filling speed, long time of grain filling, and large grain weight.