This paper studied the effects of nitrogen,phosphorus and potassium fertilization on mid-season rice by the "3414" fertilizer experiment,which was conducted in Chibi city,Hubei province.

In order to know well the hazard of abnormal temperature change to agriculture impact of low-temperature process in midsummer on seeding of mid-season rice from spike differentiation to grouting in Jianghan Plain in recent 10 years,parallel observation was used to analyze crop and meteorological factors in this study.

The grain qualities including milling, appearence, cooking and nutrition qualities of 20 middle season rice varieties (hybrid crosses) were compared between their main cropping rice and ratooning cropping rice.

With orthogonal polynomial the relationship between middle season rice yield and meteorological factors (air temperature,precipitation,sunshine time)during ear differentiation, heading and seeding stage of middle season rice over the years in Jingzhou City was analysed.

Effect of the amount of N application for bud development on the ratooning ability and in association with ratio of source to sink in mid-season hybrid rice;

Relationship between the efficient amount of nitrogen application for bud development and the source-sink structure at full heading stage of main crop in different amount of nitrogen application of main crop and ratooning rice was investigated using II-you 602 ,a mid-season hybrid rice combination.

Mid-season hybrid rice was regard as reserving ratooning rice at present in China,it is suitable local effective cultivation pattern which was used fully light hot resources of idle period in autumn and increased output,and it was the bigger application area in south rice area.