Study On Cotton Seed Vigor And The Biological Characteristics Over Different Harvest Time

Cotton is one of the main pillar industries of China's agricultural production, cotton seed and cotton production level of quality is closely related to the production of high-quality seed is one of the main tasks of cotton breeding. Seed quality effect on cotton production performance is the seed quality and variety quality. Seed vigor is a new field of seed physiology, based on plant physiology, biochemistry and genetics-based frontier. Currently, seed vigor is one of the most reliable indicators of the test seed quality. In this study, cotton seed vigor, cotton seed development through different harvest storage substance content, conduct research on cotton seed lipase activity in different collection period, cotton seed dormancy characteristics, in order to facilitate and improve the promotion of quality cotton seeds seedlings, cotton seed for the future to provide a theoretical basis for the production of seed. The results are as follows:1. Cotton Xinluzao material No.48, respectively, in boll opening day (Day 0), the first 10 days after the opening of a boll, seed boll opening the first 20 days after the harvest, field production by seed harvesting is controlled by the indoor standard germination test, analyze the different harvest seed germination and seed vigor index germination rate related, vigor index determination, the results showed that:Xinluzao No.48 boll opening 10 and 20 days seeds have significant differences between contrast in germination index, vigor index, there were no significant differences between boll opening day seed, seed germination index and vigor index of after 20 days were the highest, boll opening day seed's lowest.2. Xinluzao No.48 boll opening day, the boll opening 10 days,20 days of boll seed production field is harvested materials, different changes during maturation and Content of the moisture on seed germination of study. The results showed that:with the increase of boll opening time, the water drop, the germination rate is on the rise, free amino acid content changed little, there was a significant difference between the control and the boll opening 10 days,20 days of boll opening free amino acid content, and control boll opening day there is no difference between; boll opening day of a minimum fat content, control and boll boll 20 days 10 days and there was a significant difference; it can be said seed boll opening day of the highest water content; boll opening 20 days minimum protein content; fat up to 10 days of boll opening;3. Cotton Xinluzao No.48 different harvest boll opening day, the first 10 days after boll opening,20 days after the opening of a boll, seed production harvested field as experimental material, cotton seed extract lipase through different methods to study the different Seed harvest of lipase activity. The results showed that:10 days after harvest of seed boll highest lipase activity, followed by; boll opening day, the first 20 days boll opening control. This shows the maturity extension of seed cotton bowl opening time is different, it has a certain relationship with the seed lipase activity, boll opening day of the harvest of the seeds are not fully mature, lipase activity is low, although the first 20 days of boll seed is ripe but the fat activity decreased to aging. Therefore, appropriate and timely harvest maturity, to improve the quality of seeds and cotton seed production to provide a theoretical basis.4. In order to improve cotton seed vigor, using potassium nitrate aqueous solution GA, high and low temperature processing methods for cotton seeds caused, by measuring the cotton seed germination rate, seedling length, root length, fresh weight and the dry weight of seed vigor study results showed that:potassium nitrate at 0.2% concentration, GA at concentrations of 0.05%,4 ? during 24 h treatment, cotton seed germination rate is improved. GA3 at concentrations of 0.1%, the seedling length of the longest; KNO3 seedling root longest at concentrations under 0.3%, KNO3 concentrations under 0.2 percent in seedling fresh weight and dry weight of the highest. So it can explain 0.05%GA3,0.2% KNO3, low temperature (4? 24 h) has cotton seeds to break dormancy and improve the effectiveness of seed vigor.5. The selection of the northern region planted more than two dozen varieties of cotton material, through the indoor germination and field germination vigor comparison method, the main research of different varieties of indoor seed germination and field emergence of differences, mainly measured at different cotton varieties seed germination rate, germination index, vigor index, simple vigor index. The results show that:the difference between the varieties of germination and field emergence rate significantly, CCRI 17 highest germination rate of 98%, but lower field emergence; Xinluzao No.l, Giza 81, YCJ-5, Jin cotton 10, off GuanNong No.1, CQJ-2 and other species germination index and vigor index higher germination rate was also higher in the field. Use vigor index, germination index to further analyze the differences between the southern and northern varieties vigor, while a single seed germination rate cannot evaluate the quality. It can be combined according to field and indoor vitality indicators to filter out high vigor seed cotton germplasm material.