The Study On Epidemic Factors And Integrated Control Technique Of Jujube Black Spot Disease In Southern Xinjiang

With the dramatically growing of Xinjiang jujube industry,Jujube black rot gradually become one of the main factors affecting the yield,quality and safety of jujube.The daytime diffusion law,space distribution law and dynamic of spore during growth period were studied by the spore capturing technology combined with field investigation method.Meanwhile,the effects of different cultivation patterns,cropping patterns and irrigation mode,different soil properties,different varieties resistance and climate factors such as rainfall,mean temperature by the meteorological data in four year on red jujube black rot were studied.Further,the prevention and control of environmentally friendly pesticides on red jujube black rot were studied by toxin determination in dish and field efficacy and control test.At the same time,the field control test of 0.5% chitosanthe was done.These results will provide the basis for the prevention and control of Jujube black spot disease in southern Xinjiang.The findings are as follows:(1)The spores of Alternaria alternata could be captured throughout the day,and the proliferation peaks were between 12:00 and 13:00.The distribution of spores was concentrated in the crown of the jujube tree and below.During the growth of date trees,spores popular had certain regularity that there were very little in leaf stage,they were gradually increasing in the flowering period and reached the maximum in the flowering period.And then as the flowers decreased,the spores decreased,the number of spores started to rise again in fruitlet period,reaching the maximum in the late stage of the fruit growing.(2)The occurrences of black spot disease were affected by plant pattern and climatic conditions.The survey found that diseased fruit rate of the plant spacing include 1 * 1.5 m and 1 * 0.75 m was higher than1 * 1.5 m and 3 * 2m,and the lowest was3 * 2 spacing pattern.Summer pruning determined the time of flowering,in late May,the diseased fruit rate was the highest,in late June and early July,the diseased fruit rate was lower.The large water irrigation pattern was higher than that of drip irrigation pattern.The diseased fruit rate was higher in the clayey soil than in the sandy soil.There are three varieties in the southern xinjiang.Junzao was the poorest on disease resistance,then Jinchang,and then Huizao.The effects of climate factors such as rainfall and temperature in October were the most important to date black spot.(3)The result of the determination of the toxin in a dish showed that different medicaments had different inhibitory effects on black spots.The Difenoconazole 10% WG had strong inhibiting activity of mycelial growth,and Carbendazim 80% WP had the poorest inhibitory effects.In the field efficacy trial showed that Difenoconazole 10% WG was better than other medicament.(4)The field effect test of 0.5% chitosan showed that the control effect on the black spot was significantly higher than that of medicament.The fruiting was also superior to conventional control and it was safe to jujube trees and was harmless to flowing and fruiting.(5)Based on the previous research,the comprehensive control technologic system of jujube black spot disease was integrated.The comprehensive prevention and control strategy was put forward to select disease-resistant varieties,clean jujube orchard,cultivation control,biological control and chemical control.