Agronomic Performance of Different Japonica Rice Varieties in Different Eco-regions in Jiangxi Province

Compared with two indica hybrid rice varieties(II-you 838 and Tianyouhuazhan),a three-site experiment(Xinjian,Fuzhou and Ji'an) was conducted to investigate the agronomic performance of different japonica rice varieties in Jiangxi Province.The results showed that,overall,the yield of hybrid japonica varieties was higher than that of conventional japonica varieties,and late japonica rice performed better than semilate japonica rice.At Xinjian site,the late hybrid japonica rice obtained the highest yield with the semilate conventional japonica rice the lowest,the sowing dates were 30 May and 19 June(30-day-old seedlings at all the sites).The yield of the late hybrid japonica rice averaged 10.95 t/hm2 whose sowing date was 30 May,significantly greater than that of the control indica hybrid rice.At Fuzhou site,the yield of the control indica hybrid rice was the highest with the semilate conventional japonica inbred rice the lowest,whose sowing dates were both 30 May and 29 June,while there were no significant differences among the late conventional japonica rice,semilate hybrid japonica rice,and late hybrid japonica rice.At Ji'an site,the indica hybrid rice obtained the highest yield with the semilate hybrid japonica rice the lowest,the sowing dates were 30 May and 9 June.The late hybrid japonica rice and semilate hybrid japonica rice yielded the highest,the sowing dates were 19 June and 29 June,respectively,but did not significantly differ from the control hybrid indica rice.The optimum sowing date for high yield was 30 May at both Xinjian and Fuzhou,while that was 9 June at Ji'an.At Xinjian site,the yield of japonica rice varieties derived from Zhejiang Province was the highest with the both sowing dates,but did not significantly differ from those derived from Hubei Province and the control hybrid indica rice.At both Fuzhou and Ji'an sites,the yield of japonica rice varieties derived from different native areas did not show a consistent trend,depending largely on the sowing date.Therefore,it can be concluded that the suitable region for japonica rice planting in Jiangxi Province may be the Poyang Lake plain and the area north of it,and that the optimum variety type is the late hybrid japonica rice introduced from Zhejiang Province due to the similar latitude.