论文部分内容阅读
青藏高原小麦高产原因的传统解释认为：高原地区太阳辐射强、温差大、光温配合好，小麦光合作用强度高，呼吸消耗小，有利于更多地积累同化产物。而研究表明：在高产条件下，高原小麦日平均干物质累积速率略低于平原地区。传统观点不能对此作出很好解释。事实上，青藏高原ＣＯ２密度低会严重制约小麦的光合作用；但高原太阳辐射强、群体结构有利，这在一定程度上补偿了ＣＯ２的不足，使得其日平均干物质累积速率仅略低于平原地区。高原年均温低导致小麦的生育期远长于平原地区，因此，单季小麦能够更长时间地利用各种生态条件。略低的干物质累积速率和长得多的生长期决定了青藏高原的干物质单产高于平原地区；收获指数高的小麦在高原获得了创记录的高产。
The traditional explanation for the high yield of wheat in the Qinghai-Tibet Plateau is that the solar radiation in the plateau is high, the temperature difference is large, the light and temperature are well matched, the wheat photosynthesis intensity is high and the respiratory consumption is small, which is beneficial to accumulate more assimilation products. The research shows that: under high yield conditions, the average daily dry matter accumulation rate of plateau wheat is slightly lower than that of the plain. The traditional view can not be a good explanation for this. In fact, the low CO2 density of the Tibetan Plateau will seriously restrict the photosynthesis of wheat. However, the plateau has strong solar radiation and favorable population structure, which compensates for the shortage of CO2 to a certain extent, so that the average daily dry matter accumulation rate is only slightly lower than that of the plain area. The annual average temperature in the plateau causes the growth period of wheat to be much longer than that in the plain area. Therefore, single season wheat can utilize various ecological conditions for a longer time. Slightly lower dry matter accumulation rates and much longer growing seasons led to higher dry matter yields in the Tibetan Plateau than in the plains; wheat with high harvest index achieved record high yields in the plateau.