| 1. Establishment of high-efficient production system for hybrid cotton Lumianyan-15From parents reproduce to breeding base building, the high-efficient product system for hybrid cotton Lumianyan-15 was established and perfected. Including organization and management system and technique system , and detailed standard and experiment test was made on every concrete part. It became the first system for scale breeding of Bt-transgenic hybrid cotton, and realized scale breeding field product 1500kg per hm2 and made the highest record for seed cotton 4974 kg per hm2 and seed 2985 kg per hm2 in nation. It improved our country 's hybrid crossing seed production into a new level.2. Limited cultivation technique of transgenic hybrid cotton- lumianyan-15There was little difference in average lint percentage and pests occurrence between hybrid cotton plant with and without vegetative branches. Vegetative branches caused such negative effects as reduction in economic index, boll numbers, and average weight of total bolls on the whole plant or on the fruit branches, where as resulted in such positive effects as increase in total boll numbers and biological yield, contribution of partial economic yield, and saving some labor power for removal of vegetative branches. In this fieldexperiment, lint yield of cotton plant with vegetative branches was 3%-20% more than those without vegetative branches. Retaining two and total vegetative branches contributed over 40% and 50% of the total economic yield, respectively.Based on this experiment, suitable densities of lumianyan-15 in different environmental conditions were found out. It would be suitable 36000-42000 plants per hm2 in north cotton area of Shandong and 33000-39000 plants per hm2 in west-south cotton area of Shandong and 18000-24000 plants per hm2 in Huaihe River valley. The good condition field can have upper density limitation and bad condition field in the verse. Remove the redundant bud with vegetative branches can save labor force. The field condition and cotton plant density determine number of branches per plant. All vegetative branches can be retained in good conditions and low densities while only two vegetative braches can be saved in bad cultivation conditions and high dentisites.3. Less seeding-rate cultivation technique of transgenic hybrid cotton-lumianyan- 15The result showed that less seeding-rate cultivation did not affect cotton plant developmental period, but enhanced individual plant growth and development, and resulted in earlier closure between two rows. The compact cultivate technique was an effective way for hybrid cotton planting, which could reduce labor force and greatly save cost, while yield remained stable. The main points of this technique were to lessen the seeding rate (less than 15kg per hm2), reduce the plant density (22500~37500 plants per hm2), and keep two vegetative branches near the 1 st fruit branch.This technique was suitable for double-harvesting system of west-south cotton area of Shandong and single-harvesting system of west-north cotton area and east cotton area of Shandong. It can be used in middle fertility andhigh fertility field. Specific techniques, especially plant density, should change with the fertility level and water condition of the field. Compared with traditional cultivation, this technique made great use of individual plant's growth superiority and yield superiority. Therefore, use of the BT-transgenic hybrid cotton Fl seed with higher growth power and higher yield potential was the important guarantee of high yield.The building of high-efficiency hybrid cotton production system and suitable cultivation technique for lumianyan-15 improved cotton farmers' science idea and scientific level in planting cotton, promoted the industrial structure regulation and made the hybrid seed production into a high labor density industry which suitable our national condition. The application and dissemination of BT-transgenic hybrid cotton in huanghuai-river valley was improved into a new level. |
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