Occurrence Of Grey Mould Disease In Greenhouse-grown Strawberry And Tomato Of Hubei Province And Correlations With Epidemic Factors

Grey mould of strawberry and tomato in greenhouse caused by Botrytis cinerea is a worldwide disease.The objectives of this study are to explore the occurrence and influence factors of strawberry and tomato grey mould in Hubei province.Each three representative tomato and strawberry greenhouses were selected in strawberry planting base of Hubei Province of Agricultural Sciences,Wuhan and Wuguying Village tomato planting base,Wuxue,respectively.Combined with moisturizing culture method and specific PCR to detect the rate of colonization on healthy plant tissues,systematic investigation of the dynamics of different plant tissues at different growth periods.The relationship between different epidemic factors and the occurrence of grey mold in strawberry and tomato were analyzed,and choose a factor that has a significant correlation with the disease incidence of fruit to establish a linear regression equation.The results could make us understand the relationship between different epidemic factors and the occurrence of grey mold in strawberry and tomato.The results were shown as follows:(1)The results of the dynamic and influencing factors of strawberry Botrytis cinerea in the greenhouse showed that the strawberry tissue with grey mould in the greenhouse can be detected in late December.The peak of infection rate of fruit is the mid to late March and early May.infection rate peak of flowers appeared in early January,late February and in the mid to early April,there is no obvious peak period of infection rate of leaf.The occurrence of grey mold in strawberries was observed in the late December in the field,and peak incidence of fruit is in early March,late April and early May.The peak incidence of flowers is in early March and early May,and there is no obvious peak period of leaf disease.The correlation analysis was conducted on the incidence of two strawberry fruits in the two greenhouses.The incidence of flowers,the incidence of the leaves,the infection rate of the fruits,the infection rate of flowers,the infection rate of leaves,temperature,and relative humidity were analyzed.The incidence of flowers,the infection rate of fruit,the infection rate of flowers,the infection rate of leaves,and temperature have a significant correlationwith the incidence of strawberry fruit.The results showed that the rate of fruit infection,the incidence of flowers,and the temperature have a good fit between predicted and actual values.Effects of different maturity stage on the occurrence of Botrytis cinerea in strawberry fruit were evaluated.The results showed that the incidence of red maturation period was stronger than the green ripening stage,white mature stage and pink ripening stage.(2)The results of dynamic and influencing factors of tomato Botrytis cinerea in the greenhouse showed that Botrytis cinerea in greenhouse tomato leaves can be detected in early to the mid March.The infection rate of flowers can be detected in early to the mid April.The peak period of leaf infection rate were in late March,late April,late to the mid May and early June.The peak period of the infection rate of flower is in late mid April,late to the mid May and early June.As a whole,the infection rate of flowers was higher than the infection rate of leaves.Dynamic disease investigation in the field revealed that tomato leaf grey mold disease began to appear in the middle and early of March.Diseased flowers were found in the middle and early of April.Dieased stems start to be observed in the middle to late April.Diseased fruit begins to be observed at the end of Apri.Eearly April,late April and early June is the peak period of leaves incidence.The first half of June is the peak period of flowers incidence,and the peak incidence of stems is in late May and early middle of June as well as the peak period of fruit incidence is mid-late May and mid-June.The Pearson correlation analysis was conducted on the incidence of tomato fruit in two greenhouses,and the incidence rate of flowers,leaf incidence,stem incidence,the infection rate of flowers,the infection rate of leafves,temperature,and relative humidity.The incidence of flowers,the incidence of leaves,the infection rate of flowering,the infection rate of leaves,relative humidity are significantly correlated with the incidence of tomato fruit.The results showed that the incidence rate of flowers,the infection rate of flower,and the infection rate of leaves were well fitted.The results of inoculation of tomato fruit of different maturity stage with Botrytis cinerea showed that the incidence of white maturation period and color change periodwas relatively severe than the green ripening period and red maturation period.Effects of Botrytis cinerea on fruit incidence under different temperature and humidity and moisturizing time based on fruit inoculation were evaluated.Grey moldwill occur in different moisturizing time under the temperatures 10-25?.After moisturizing 12 hours,the lesions spread significantly.It is necessary to moisturize12 h that have disease at 30?.At the best temperature of 20?,at least moisturization of 36 h were needed for disease.At 10? and 30?,it takes more than 4 days for the disease to develop.The lesion diameter of tomato grey mold increases with increasing relative humidity at 20?.The relative humidity of the fruit needs to reach 66% under the condition of injury and relative humidity need to reach 92% before injury without injury.No matter whether the fruit is inoculated or not,maximum lesion diameter were found at 100% relative humidity while no lesions are produced at a relative humidity of 20%.The survival time of tomato diseased body from different soil moisture: dry soil>semi-humid soil> wet soil.The survival time of tomato diseased body from different soil depth : soil surface> 10 cm below soil> 20 cm below soil.