Abstract: The factor given rise to keng was not greatly developed in the South Henan is low product,serious disease and pest and poor quality.The basic reasons of above mentioned were that keng was cultivated in the ecosystem of high temperature and high moisture.The only method to resolve the above problems is to delay the filling and mature period.The mature period is delayed from the present 9.1 9.10 to 10.10 10.20.The main metecrologic factor in Xinyang for 48 years shown that delaying keng mature period will f...