Research On Screening Methods And Indexes Of Drought Resistance Of Transgenic Maize And Comprehensive Evaluation

This experiment adopts 111 pieces of transgenic maize materials, including 48 transferring BC genes; 42 transferring PK genes; 12 transferring RT genes; 9 transferring H, q genes. The experiment is conducted in pots. In seedling stage and flower stage respectively, all indexes are measured in heavy stress when the water content of soil is 7.8%, wither coefficient is 6.83% and recovery water . Through measuring indexes, including of the length of root, number of root, the extent to leaf curling, relative electrical conductivity rate, relative water contents of leaves, photosynthesis rate ,transpiration rate, water potential of leaf, water conservation ability of leaf, the yield, the effect of indexes to drought resistance of transgenic maize is analyzed and probed into. At the same time , the relativity of the relative electrical conductivity rate, relative water contents of leaves, photosynthesis rate and transpiration rate are examined mutually. As a result, subordination degree is introduced and regarded as a comprehensive evaluation way .The result show:1 .When screening drought resistance of transgenic maize, the length of root, number of root, fresh weight, dry weight, and root-cap ratio can be regarded as effective morphology indexes, at the same time, relative electrical conductivity rate, relative water contents of leaves, photosynthesis rate, transpiration rate, water potential and water conservation ability of leaf after 24 hours are regarded as physiology indexes. And the curling extent of leaf can be thought of as a reference index.2.Recovery water can be regarded as a way of screening drought resistance index.3.When screening drought resistance of transgenic maize, seedling stage is primary and flower stage may be subsidiary.4.Subordinative degree can be regarded as an effective comprehensive appraise of screening drought resistance.5.The means of transferring gene can improve drought resistance. The different transgenic maize materials have different drought resistance. That is RT>BC>PK>H.6.Subordinative degree is an efficient method of cultivating drought resistance maize in dry land and semi-dry land.