Study Of Heat Tolerance In Line Pepper Varieties

The pepper (Capsicum annuum L.) is a solanaceae panicum miliaceum,which is thermophilic but cannot tolerate high temperature.The line pepper is a important type in China.At present the line pepper has become the main economical crop in many areas of our country.It is necessary to study on the heat tolerance of peppers as the heat damage in summer.In this study,6 pepper varieties, which are common in market,were treated under 30℃,35℃ and 40℃ to identify the heat tolerance at germination and seedling stages and study the influence on physiological-biochemical characteristic.This study still investigated the campestral agronomic characters of the 6 pepper varieties in midsummer.The main results were as follows:(1) The results of germination test show that’Xinxiang No.24’ and ’Hangjiao No.1’ are germination heat resistant varieties;’Xinxiang No.2’ and ’Xinxiang No.8’ showed moderate heat resistance;’Lafeng No.3’ and ’Nongda 8819’are heat sensitive varieties in germination stage.(2) The results of seedling heat damage index show that:’Xinxiang No.8’ and ’Xinxiang No.24’are heat resistant varieties;’Xinxiang No.2’,’Hangjiao No.1’ and ’Lafeng No.3’ are moderate heat resistant varieties;’Nongda 8819’ showed low heat resistance.(3) The results of field trail show that:’Xinxiang No.8’ and ’Xinxiang No.24’ showed high heat resistance;’Xinxiang No.2’,’Hangjiao No.1’ and ’Lafeng No.3’are moderate heat resistant varieties;’Nongda 8819’failed to resist high temperature in the field.(4) As the increasing of temperature,the SOD activity rose first and then fell; the content of Pro and MDA continue to rise; there is not significant correlation between the POD activity and heat resistant ability.(5) The comprehensive analyzing results show that:the results between germination identification method and field identification method were consistent in general.The seedling identification method has high consistency with field result, and it is always accurate and stable.