The Main Disease And Preventing And Controlling Measure Research Of Qu Zhou Pankan In Storage Period Under Unusual Climatic Conditions

On the foundation that Qu Zhou Pankan (Citrus poonensis Hort.ex Tanaka) and the technology of maintains freshness have been systematically summarized, this article emphatically conducted the investigation and research to the main disease of Qu Zhou Pankan in storage period under unusual climatic conditions, and studied the reason why Pankan was rotten under unusual weather and discussed the preventing and controlling measure, and carried on a experiment to the effect of the commonly used antistaling agent in market and new medicament, which is used to preventing and controlling the main disease of Qu Zhou Pankan in storage period and maintaining it freshness. The following results were obtained:1. During the earlier period, the intermediate stage and the later period which Pankan stores, the total incidence rate of disease of the fruit, which was picked 2 days after rain obviously was higher than picked 14 days after rain. Without any antisepsis measure to maintain freshness, the blue mold and the green mold were the main diseases of Qu Zhou Pankan in storage period, accounted for 27.01-86.36% of the total outbreak fruit. But when the fruit was picked in or after rain, the tan rot became the main disease in storage period. In each storage period, the incidence rate of the tan rot of the fruit, which was picked 2 days after the rain was higher than the blue mold and the green mold in the same time, also all could be taken bad in the entire storage period. The black rot and the anthracnose were taken bad rarely in the earlier storage period, and was taken bad heavily in later period compared to the earlier period.2. The year in which the picking period of Pankan was under unusual climates, in which the commonly used antistaling agent is less effctive than in normal years , the primary cause was the secondary disease that the tan rot became the main disease. When the picking period in autumn is under dry clear weather, the incidence rate of the tan rot is extremely low, so the tan rot has not been included the main preventing and controlling objects in storage period of Pankan. But in unusual years which snow and rain frequently, this disease occurs actually high, it can appear massively rotten in the preparing storage period.3. At present, imazali, prochloraz and guazatine, these three kinds of antisepsis disinfectant which are promoted to be widely used is still excellent medicament to prevent and control the blue mold and the green mold, might be single to use, mix to go together with or alternative usage, of which the preventing and controling efficieny even reach above 98%, but these three disinfectants have no effect to prevent and control the tan rot of Pankan. A new fungicide "shi yun" (dimethomorph) has a obvious effect to prevent and control the tan rot of Pankan in storage period. After handling 20 days, the result which was handled by three kind of different dilutions (500×, 1000×and 2000×) of "shi yun" to the tan rot of Pankan was obviously higher than handled by the clear water. but to 60%, 20 days after the drought happened. The Pankan which was handled with three kind of different dilutions of "shi yun" had not been taken bad even till 80 days. The disease fruit number was zero. The preventing and controlling effect on the tan rot reached 100%.4. On the foundation of the results of predecessor's research, according to my related research and practical experience for many years, We have systematically summarized a set of applied implementatary technology to store Pankan and maintain it freshness.