Screening Indexes For Heat-tolerance Seedling Stage And Evaluation Of Heat-tolerance On Different Germplasm In Eggplant

Eggplant(Solanum melongena L.)is a genus of Solanaceae,which has a long history of cultivation in China.It is one of the main vegetables in china.It is found that the continuous high temperature over 35 degree is not conducive to the growth and development of eggplant.Even result in a significiant reduction in production,thus causing huge economic losses to growers.At present,the most fundamental and most effective way to solve the problem of high temperature heat damage is to select heat resistance Eggplant germplasm materials.Therefore,the selection ofheat resistant identification index is very important for this.This experiment selects long eggplan?line eggplant?egg eggpant ?round eggplant this 4 different cultivars as materials,determinated heat injury index?relative electric conductivity?relative chlorophyll content ?MDA content ?Soluble solids content and proline content under high temperature,studied the relationship between changes in this 6 kinds of physiological and biochemical indexes and morphological indexes of eggplant seedlings,drawn three kinds of simple,rapid and effective index.Then the three indexes were used to evaluate the heat tolerance of Eggplant Germplasm from 20 samples.The main results are as follows:1.The index of heat resistance of eggplant varieties was obtained by the index of heat damage from the index of heat damage under the artificial simulated climate condition,and the difference between varieties was obvious.The method is simple and easy to operate,so the method can be used to identify the heat tolerance of eggplant seedlings;2.The results of this study showed that the relative conductivity of cell membrane was significantly correlated with the heat injury index under high temperature stress;3.Soluble sugar as the main osmotic adjustment substances,which has a important role in improving the resistance of plants to high temperature.In this study,there was a significant correlation between heat damage index and relative conductivity.Thus,Soluble sugar content could be used as a reference index to evaluate the heat tolerance of eggplant;4.The data shown that the correlation between relative chlorophyll content,content of MDA,content of proline between heat injury is very samll,which means that this indexes can not reflect the heat resistance among the varieties very well.Therefore the three indexes cannot suitable as a measure of heat resistance index of eggplant;5.By measuring 20 Eggplant Germplasm heat injury index,relative conductivity,soluble sugar content change under high temperature conditions,through comprehensive analysis,found that: E-4,E-7,E-11,E-21 of the four materials in thermal damage under the condition of heat injury symptoms is not obvious,the heat damage index is low;under high temperature stress the conductivity remains low;soluble sugar content decreased slightly after heat injury.Combined with the above statistics,E-4,E-7,E-11,E-21 these 4 heat-resistant material were selectd.