Selection And Utilization Drought Resistance Indexes Of Buckwheat

Buckwheat is one kind of important especially plant resources, there is rich nutrition and bioflavonoids; it is one of the most deveiopment potential crops in 21st century. The buckwheat mainly distributes in the arid and semi-arid areas in Midwest China, it is the staple food crops and the industrial crop in there. But the production conditions are bad in Midwest China, while drought is a big limitation factor to yield. How to quickly and accurately identify species for promotes the production and the industrial development in buckwheat production area has a very important significance.The experiment through the field test and laboratory analysis, use the way of drought stress simulated by PEG and selection of arid ecological condition, studied morphological indexes and physi-biochemical indicators of buckwheat seed germination, seedling of different genotype varieties, as well as studied the antioxidant protection mechanism, agronomic characteristics, and correlation analysis of physi-biochemical, agronomic characteristics and the drought resistance index of buckwheat leaves under different ecology area and water control in rain shelter conditions, for screening identification indicators. Identification index of drought resistance during bud, seedling and late growth stage had been established preliminary. The effeets of water stress on morphological, physiological, biochemical and grain yield had been carried out deep research. This paper adequately expounded and proved the relationship between physiological and biochemical characteristics and drought resistance in buckwheat. The main conclusions are as follows:(1) Osmotic stress in the seed germination test, through various characters relative value make drought grade to various varieties, afterward various targets and drought resisting rank make correlation analysis and grey relational grade analysis. The results showed that root length stress index, related germination energy, related germination rate, index of relative water content, was significant instructions on different drought resistances, and had positively correlated with drought resisting rank. Through grey relational grade analysis, they had a higt correlation degree. They can be used as an effective index for drought resistance identification in the seed germination of buckwheat.(2) Osmotic stress in the seedling test, the determinated result of survival rate and various targets content were the same conclusion with the reault of drought resistance identification in seed germination test, through various targets and survival rate make correlation analysis and grey relational grade analysis. The results showed that chlorophyll in leaf, MDA in leaf, SOD in root, soluble protein in leaf, was significant instructions on different drought resistances, and had positively correlated with survival rate, they had a higt correlation degree. They can be used as an effective index for drought resistance identification in the late growth stage of buckwheat.(3) In water stress research of buckwheat, the determinated result of SOD, POD, MDA, O2-, chlorophyll and soluble protein content were the same conclusion with the osmotic stress in seedling stage, and had significantly related with drought–resistance of wheat varieties, further more, SOD, POD, chlorophyll was a positive correlation with drought resistance index and reached extremely significant level, MDA was a negative correlation with drought resistance index and reached extremely significant level. Through grey relational grade analysis, POD, soluble protein, SOD had a higt correlation degree. All agronomic characters of buckwheat have reduced under water stress. The agronomic traits of drought resistance buckwheat varieties were affected less under water stress, the drought index of the species reached significant level. 1000-seedweight, yield was a positive correlation with drought resistance index and reached extremely significant level, nodes of main stem, seed weight by plant was a positive correlation with drought resistance index and reached significant level. Through grey relational grade analysis, seed weight by plan and nodes of main stem had a higt correlation degree. They can be used as an effective index for drought resistance identification in the seedling of buckwheat.(4) In different ecology area research of buckwheat, through common buckwheat and tartary buckwheat's agronomic characters and yield make correlation analysis and grey relational grade analysis. The results showed that nodes of main stem, growing period, 1000-seedweight is closely related to yield of common buckwheat, they are main factors effecting on yield of common buckwheat. Seed weight by plant, plant height, 1000- seedweight is closely related to yield of tartary buckwheat, they are main factors effecting on yield of tartary buckwheat.