不同熟相小麦品种生育后期的群体光合强度及同化物的运转分配

用CXH-305型红外CO_2分析仪和同位素示踪技术研究了4个不同熟相小麦品种生育后期的群体光合强度和同化物在不同器官中的运转分配。结果表明,落黄较好的小麦品种,其籽粒灌浆初期的群体光合强度与落黄较差品种无显著差异;但到籽粒灌浆中后期,前者的群体光合强度则极显著地高于后者;到籽粒灌浆末期,落黄较好的品种仍维持相对较高的群体光合强度。~(14)CO_2示踪研究表明,在小麦生育后期,落黄较好品种植株各器官的放射性比活度高于落黄较差的品种。就同化物的运转分配而言,在籽粒灌浆期,落黄较好品种光合产物运输到茎秆和根系的比例较大,而落黄较差的品种运输到穗部的比例较大。文中讨论了不同熟相小麦品种产量差异的生理原因,并就小麦生产中的有关问题提出了建议。

MASS PHOTOSYNTHESIS AND DISTRIBUTION OF PHOTOASSIMILATES OF WINTER WHEAT VARIETIES WITH DIFFERENT MATURITY FEATURE

The mass photosynthesis rate and distribution of photoassimilates of winter wheat varieties with different maturity feature were studied using GXH - 305 portable CO2 infred ray analyzer. The mass photosynthesis rate of winter wheat varieties with better maturity feature showed little difference from the varieties with general maturity feature during the early stage of grain filling phase. However, the mass photosynthesis rate of the former was significantly higher than that of the later during the middle and late stage of grain filling. The study with 14CO2-tracing method showed that the relative activity in different organs of varieties with better maturity feature was singnificantly higher than that of varieties with worse maturity feature during the late growth stage of winter wheat. The rate of photoassimilates distribution in stalk and root system of winter wheat varieties with better maturity was higher than that in the others organs. The physiological mechanism of difference of grain yield and plant decay in varieties with different maturity feature were also discussed.