Studies on the Wind or Storm-Damages to Paddy Rice Plant in the Stages before and after Heading

[摘要] With the object of throwing more light on the mechanism of deterioration of fertility of wind-damaged rice plant, a series of experiments were conducted in which potted rice plants of various stages (during 20∼30 days before and after heading) were treated with wind (15.5m/sec. hr.), and their nutritional status after treatment were examined. The following conclusions are drawn from this study. 1) Water absorption of wind-damaged rice plant increased with the rapid increase of transpiration rate ; however, as a whole, water economy of the plant was in unbalance, and leaf-withering occured, moreover, differentiation and development of growing region and panicle came to be retar ded. 2) The occurrence of leaf-withering not only cheked the transpiration rate, but also decreased water absorption by and through root, as a result, the physiological function of root degraded the absorption of solutes, their translocation, accumulation and metabolic activity were retarded. 3) The increased leaf-withering and the reduction of capillary and constitutional water hindered carbon assimilation ability, while increased respiration rate resulted the accelerated consumption of assimilated products; this, in turn, caused further nutritional deficiency. To sum up, it is concluded that the traditional views "that the deterioration of fertility of wind-damaged rice plant is to be attributed to a direct injury by wind or storm", lacks experimental bases. On the other hand, it now seems a reality that the deterioration of fertility of wind-damaged rice plant is caused by subsequent nutritional disturbance. This is especially accountable for the fact that damages of rice plant after the Earforming stage are markedly severe.

[学科分类] 农业科学（综合）