Ecological Adaptability And Cultivation Of Different Japonica Rice Varieties

Indica rice plays the most important role in rice plantation of Hubei Province for a long time. To meet market needs, a so called’replacing Indica by Japonica’ project was initiated and carried out. The primary task of this project is to introduce adapted species of Japonica rice and investigate their adaptability in different ecological areas as well as corresponding high-yield cultivation technology, eventually providing theoretical basis for the establishment of a high-yield cultivation technology system of Japonica rice. With41species of Japonica rice as experimental materials and Indica rice yangliangyou6as control, choosing3different ecological area including northern Hubei (Xiangyang), central Hubei (Jingmen) and Jianghan Plain (Gongan) as experimental sites, the species were carefully selected in this study. With Japonica rice yongyou1512, huhan3and indica rice yangliangyou6as materials, I studied the effect of N fertilizer, sowing time and density on rice yield as well as corresponding high-yield cultivation technology. The mathematical model of japonica rice high-yield plantation in Hubei was established to select the most suitable species. The purpose of this study was to confirm the optimal sowing time, N fertilizer level and transplanting density of these adapted species of Japonica rice with high yield, thus providing technical support for the scientific selection of japonica rice species and reasonable area layout, as well as industrial development of japonica rice in Hubei Province. The results were as following:(1) The experiment on species selection showed that: the growth duration of16species including Yongyou1538, Yongyou4138, et al., was not significantly different from ck’s. Five species including Wuyun Japonica rice21, WDR60, Huhan3and Changyou10-7were sensitive to temperature and light variations. In terms of rice appearance and processing quality, the brown rice rate of5species including Yongyou4901, Wuyun Japonica rice24, et al., was higher than ck’s. The milled rice rate of5species including mid-rice1, Huaidao5, et al., were significantly higher than ck’s. The chalky rate of7species including Yongyou4949, Wuyun Japonica rice24, et al., was not significantly different from ck’s. Yongyou1538and Yongyou4138in3ecological areas including Xiangyang, Jingmen and Gong’an were basically similar with their controls, while the yields of Huaidao5, Ningjing5, Lianjing7and Mid-rice1were10%lower than ck’s. The yields of different species in various ecological areas showed that Indica hybrid rice’s yields were higher than Japonica hybrid rice’s, and hybrid Japonica rice’s yields were higher than regular Japonica rice’s. The species including Yongyou1538, Yongyou4149, Mid-rice1and South Jing45showed great rice quality, which are apt to be widely cultivated in Hubei.(2) The experiment on secondary regression orthogonal rotary combination designed with three factors and five levels of each factor indicated that:in comparison with indica rice yangliangyou6as control, high yield of the optimized cultivation pattern in practice was that seeding, N, transplanting density should be applied between late April and early May, at the rate of19kg/667m2and2.3x104-2.641×104hills/667m2respectively in moderately fertilized soil.(3) The species that are apt to be promoted all across Hubei Province include yongyou1538, ningjing5et. al.. The species that are apt to central Hubei rice area include yongyou1538, yongyou4901, huai-rice9, et. al.. The species that are apt to central Hubei rice area include huai-rice5, yongyou1538, et al.. The species that are apt to Jianghan plain rice area include huai-rice9,yongyou1538, yongyou4138, et al.