Abstract:

The paper aims to study the root activity and grain filling characteristics of rice varieties with different growth types at the late filling stage, and to provide a reference for the cultivation of quality root system for high yield rice. In this study, field and hydroponics experiments were carried out on the representative varieties of middle early maturity, middle maturity, middle late maturity and late maturity in Xing’an League in 2018-2019. By adjusting the sowing date and the number of elongation internode, the varieties with different growth periods could heading in the same period, and the number of elongation internode of the same variety was different but the heading period was the same, so as to compare the root activity and grain filling characteristics of different varieties in the later period, and the characteristics of root activity and grain filling at the later stage of different elongation internode types in the same variety and spot. The results showed that the root activity of different rice varieties decreased after heading, and the upper root activity of all tested varieties was higher than that of the lower one in the whole grouting and filling stage. The root activity of different elongation internode varieties was significantly different in the later stage, which was mainly determined by the rooting rule and the upper root rate; the main filling duration and filling intensity of different elongation internode varieties were different. The varieties with the same number of elongated internodes had a short duration of grouting and a large grouting intensity; the varieties with the same number of elongated internodes had a long duration of grouting and a small grouting intensity. The varieties with the same number of elongated internodes had a small difference, while the varieties with different number of elongated internodes had a large difference. To achieve high yield of rice, it is necessary to use the promoting and controlling technology flexibly according to the characteristics of root and root activity of different growth types of rice, cultivate the developed and functional root system, so as to achieve the purpose of promoting high yield of rice.

Key words: growth and development type, rice, root system vitality, grain filling, characteristic research