Study on Difference in Cold Tolerance Between Weedy Rice and Cultivated Rice in Heilongjiang Province of China

摘要

A long-red awn weedy rice and rice cultivars named Ken99004(ZCl), Crossing-503(ZC2), Ken Sticky Rice(ZC3), Shashani(ZC4), Long-Grain Aromatic Rice(ZC5) were used to study typical wild traits of weedy rice and to identify the cold resistance of all genotypes. The results showed that the stem of long-red awn weedy rice was the weakest. No difference was found in the early stage of rice growth, e.g. the vegetable growth stage, between long-red awn weedy rice and other rice cultivars in the stem rigidity, but in the later stage, or reproductive growth stage, their leaves and stems were senescent rapidly because of the speedy supply of nutrients for panicle growth, meanwhile the rigidity of stem was reduced sharply just as withered weeds. The germinationrate of long-red awn weedy rice was the highest in cold condition, and in turn were ZC1, ZC2, ZC3, ZC4, ZC5, respectively. The performances of genotypes in cold tolerance were identical, those with a high ability of germination in low temperature also showed a strong cold tolerance in main traits in whole growth period, the order from strong to weak in the extent of cold tolerance were long-red awn weedy rice, ZC1, ZC2, ZC3, ZC4, ZC5, respectively.