Abstract:

【Objective】 Correlation between plant type indexes and yield components of rice as well as precise and quantitative cultivation on its mechanism of increase production were studied in special ecology area under high-altitude and cold. 【Method】 By using japonica rice landraces Dabaigu and new varieties Lijing 10 as test materials to analyze the correlation between plant type indexes and yield components at heading stage and research on growth and development as well as ecological and physiological characteristics of rice. The target of main attack on increasing production was studied to compare the precise and quantitative cultivation and conventional cultivation and the effects of precise and quantitative cultivation on plant type and yield of rice in high altitude and cold ecological area were analyzed. 【Result】 The results showed that there were differences in characteristics of plant type and grain yield components such as effective panicles, total number of spikelets among different populations. The notable characteristics of high-yield group were that the length of top three leaves were longer. The angles of top three leaves were smaller, the specific leaf weight was high at heading stage and closely related to the traits of leaves, stems and panicles. The length of internode on stem distributed reasonably, bottom internode was shorter while top internode was longer. A significantly positive correlation was observed between first branch numbers, second branch numbers and grain yield. 【Conclusion】 Enlarged sink (increased total number of spikelets) and the promoted sources (increased the leaf area index after heading stage and the specific leaf weight) were the main reasons of increased rice yield. It is concluded that synchronizing nitrogen and water application in precise and quantitative cultivation and organ formation in high-yield rice, increasing the leaf area index and simultaneously promoting total number of spikelets, rice yield could significantly increase rice yield in high-altitude eco-areas.

Key words: rice')">rice, precise and quantitative cultivation, high altitude, plant type characteristics, yield