关键词: 生物制剂, 生物制剂, 不同施药方法, 中后期条螟白螟, 防效评价

Abstract: For exploring cold tolerant gene source in rice, especially in indica rice, to promote the cold tolerant rice breeding , 18 germplasms, which were selected from 150 accessions collected from "rice germplasm repository of guangdong province" and introduced from the rice region in southern China, were used in the cold resistant rice germplasm screening test at the seelding stage. ‘Lijiangxintuanheigu’ was employed as cold-tolerant control and ‘Gui 99’ was employed as cold-sensitive control in the test. The test for the screening of cold tolerant germplasms was carried out in the phytotron by the method of the low temperature stress （PGV-36, the mean daily temperature 8.5 ℃）. The experimental results showed that: ① The growth and development of the tested materials slowed significantly under the low temperature stress, even stopped as the treatment went on; ② Under low temperature stress for 3 d or 6 d, the death rate of the tested materials was different significantly but the cold tolerance of japonica rice on the whole is better than the indica rice; ③ The death rate of the tested materials, which continued to grow 10 days under the natural environment after 3d or 6d low temperature stress, was employed as the evaluation index of cold tolerance. The cold tolerance of ‘Jing 44’ was the strongest, as its death rate was less than 25% after 8.5℃ low temperature stress for 6 days. The secondary were ‘Miao 110’, ‘2-319’ and ‘Huazhan’. The cold tolerance of ‘Yuanbaozhan’ and ‘Miao 108’ was medium, but that of the other 12 germplasms such as ‘318’, ‘R2168’ and ‘Chuangfeng 1’, etc was weak. In the cold tolerant germplasms, ‘Huazhan’ and ‘2-319’ are indica rice, ‘Miao 110’ is derived from the cross of indica and japonica, they all can be applied to cold tolerance breeding in indica rice.