Rice Ratooning Property And Its Relation To Content Of Nutriment In The Main Crop

The experiment was conducted with 32 rice varieties (hybrid crosses) including 12 two-line hybrid rice combinations, 10 three-line hybrid rice combinations and lOconbentional rice vaieties as materials. Yield and ite relations to yiekd components , and its relation to ratooning ability were studied. The relations of the content of nutriment and soluble carbohydrate in the rice culm before harvest of the main crop to yield and ratooning ability were studied as well. The main results are as follows:1. It is significant positive correlation of the seed setting percent of the main crop and the yields. It is the main factor of it' s yield. The ratoon crop' s panicle number is significant positive correlation to the yield. So it insure high yield of a year to increase the number per panicle of the main crop and the panicle number of the ratooning crop.2. The correlation between the main crop' s and the ratooning crop' s between the number per panicle, between seed setting percent and between 1000-grain weight are distinct plus correlation, while the panicle number is indistinct plus correlation. Those could offer reference for the planting pattern of the rice and its ratoon rice to choose ideal varieties or crosses. The varieties or crosses are middle number per panicle, high seed setting percent and high 1000-grain weight of the main crop.3. The yield of the Shan you 63 is highest in the main crop and the peinanyou 500 is second by comparison of the yield on six crosses. The yield of the peinanyou 500 is highest in the ratoon crop, while the yield of the Shan you 63 is fifth. The peinanyou 500 is highest in the total yield and its final ratoon ratio is the highest. So it is a ideal cross that suits the planting pattern of the rice and its ratoon rice.4. The seed setting percent to the ratoon rate is best plus correlation in the inscapes of the main crop, while the panicle number and number per panicle to the ratoon rate are indistinct negative correlation, the 1000-grain weight to the ratoon rate is not correlative. So the seed setting percent of the main crop could be the index of choosing the ratoon rice.5. The correlative coefficient of the yield of the ratooning rice to the ratoon rate is the most. The most ratooning ratio is the twenty-five after the heading of the main crop. So the end ratoon rate or the ratoon rate of the twenty-fifth is best to weigh the ratooning ability6. The nutritious elements content of the main rice at the eighth days before the harvesting to the ratoon ability and the yield of the ratoon rice is not correlative. P and N content at the harvest of the main rice to the ratoon rate is distinct plus correlation, and K content is distinct negative correlation. Ca content to the ratoon rate is not correlative. Mg is similar to the K. The four trace elements (Fe> M^ Cu, Zn) contents to the ratoon rate and the yield are not correlative. The Cu-. Fe> Mn> B contents at the harvest of the main crop to the ratoon ability are not correlative. So it is no meaning to fertilize those trace elements for increasing the yield of the ratoon rice.7. The soluble carbohycrase content at the harvest content of the main crop to the ratoon rate during the prophase of the ratoon rice is distinct plus correlative. The soluble carbohycrase content at the eighteenth day of the main rice heading to the ratoon rate is indistinct plus correlative. So the soluble carbohycrase content at the harvest content of the main crop could be the choosing index of the varieties of the rice and its ratoon rice.