不同产量水平麦田小麦光合特性和^(13)C同化物分配的差异

Differences in Photosynthetic Characteristics and Distribution of ^(13)C Assimilates of Wheat in Fields with Different Yield Levels

为明确不同产量水平麦田产量形成特征,以高产小麦品种烟农1212为材料,基于^(13)C稳定同位素标记法,选择10 500 kg·hm^(-2)(S)、9 000 kg·hm^(-2)(H)和7 500 kg·hm^(-2)(M)3个产量水平麦田,比较分析不同产量水平麦田小麦光合特性、^(13)C同化物分配、籽粒灌浆速率和产量的差异。结果表明,S麦田开花后21 d,旗叶SPAD值达52.6,比H、M麦田分别高12.15%和27.98%;旗叶净光合速率达18.8μmol·m^(-2)·s^(-1),比H、M麦田分别高14.63%和37.23%;旗叶功能期延长,有利于成熟期^(13)C同化物在籽粒中的分配和转运,在籽粒中的分配量达338.97 g·hm^(-2),比H、M麦田分别高7.22%和23.67%。S麦田在籽粒灌浆中后期保持较高的灌浆速率,成熟期千粒重达48.83 g,比H、M麦田分别高6.73%和10.68%,获得11 280.54 kg·hm^(-2)的产量。

In order to clarify the yield formation characteristics of wheat fields at different yield levels, Yannong 1212, a high-yielding wheat variety, was used as material. Based on^(13)C stable isotope labeling method, three wheat fields with yield level as 10 500 kg· hm^(-2)(S), 9 000 kg· hm^(-2)(H) and 7 500 kg· hm^(-2)(M) were selected to compare and analyze the differences of photosynthetic characteristics, assimilate distribution, grain filling rate and yield of wheat. The results showed that the SPAD value of flag leaves in S wheat field was 52.6 at 21 days after anthesis, which was 12.15% and 27.98% higher than that in H and M wheat fields, respectively;the net photosynthetic rate of flag leaf was 18.8 μmol·m^(-2)·s^(-1), which was 14.63% and 37.23% higher than that of H and M wheat fields, respectively. The extension of flag leaf functional period was conducive to the distribution and transport of^(13)C assimilates into grain at maturity stage. The distribution amount of^(13)C assimilates into grains reached 338.97 g· hm^(-2)in S field, which was 7.22% and 23.67% higher than that in H and M wheat fields. S wheat field maintained a high grain filling rate at the middle and late stage of grain filling, and the 1 000-grain weight reached 48.83 g at maturity, which was 6.73% and 10.68% higher than that of H and M wheat fields, respectively, so a yield of 11 280.54 kg· hm^(-2)could be obtained.