Study On The Effect Of ABA Application And Heat Shock On Cotton

In the cotton production areas of Hubei province, the growth and development of cotton are challenged by high temperature and drought which flowering stage and boll-bearing stage have to encounter during July and August of every year. So high temperature and drought is a crucial stress factor which block the cotton production. In this test, five treatments were given as follows: ABA cotton-leaf-spraying, ABA cotton-root-irrigated, ABA cotton-seed-soaked, seed-germinating heat-shock treatments and control. The design aims at exploring cultivation theory for effective cultivation measures.The test result showed that more proteins were expressed in the ABA cotton-root-irrigated, ABA cotton-seed-soaked and seed-germinating heat-shock treatments -than those in control. The chamber-raised seedlings produced three extra proteins with molecular weights 120kDa, 75kDa and40kDa and cotton plants in field gave two extra proteins with molecular weights 60kDa and 19kDa in the ABA cotton-root- irrigated, ABA cotton-seed-soaked and seed-germinating heat-shock treatments. Moreover, more proteins were expressed in the ABA cotton-root-irrigated and ABA cotton-seed-soaked treatments than those of seed-germinating heat-shock treatment, three extra proteins with molecular weights 61kDa, 54kDa and 44kDa in the ABA cotton-root-irrigated seedlings, four extra proteins with molecular weights 150kDa, 67kDa, 61kDa and 22kDa in the ABA cotton-seed-soaked seedlings, and two extra proteins with molecular weights 55kDa and 40kDa in the ABA cotton-root-irrigated cotton plants in field.Under the condition of high temperature and drought, the enzyme activities of SOD could be improved significantly in ABA cotton-leaf-spraying, ABA cotton-root- irrigated, ABA cotton-seed-soaked, seed-germinating heat-shock treatments. The enzyme activities of POD could be improved significantly in ABA cotton-seed-soaked treatment. The enzyme activities of CAT could be improved significantly in ABA cotton-root-irrigated, and ABA cotton-seed-soaked treatments in field, and in ABA cotton-leaf-spraying and seed-germinating heat-shock treatments in raising-chamber.The content of MDA was raised in chamber-raised seedlings in seed-germinating heat-shock treatment, and declined in ABA cotton-leaf-spraying and ABA cotton-root-irrigated treatments. The content of MDA was raised in the ABA cotton-root- irrigated, ABA cotton-seed-soaked, seed-germinating heat-shock treatments, and the content of MDA in ABA cotton-leaf-spraying treatment changed insignificantly.Vegetable growth and fruit shoots development could also be improved significantly from June 15 to August 15 and fruit shoots development could also be improved significantly from August 15 to September 15 under the condition of high temperature and droughtThe numbers of cotton bolls increased in ABA cotton-seed-soaked and ABA cotton-root-irrigated treatments from June 15th to July 15th, and the numbers of cotton squares increased in ABA cotton-seed-soaked and ABA cotton-root-irrigated treatments from July 15th to Augustl5th. The mature of cotton bolls could be prompted in ABA cotton-root-irrigated and ABA cotton-seed-soaked treatments. The fall ratio of cotton bolls and squares could be prevented in all treatments.The cotton yield of late stage and early stage could be improved in the cotton-seed-soaked abscisic acid test and the falling ratio of bolls and squares could not be prevented in all treatmentsThe qualities of cotton fibre were not influenced and the lint percent, boll weight and cotton-seed weight changed little in every treatment tests...