| Banana is one of the most famous tropical fruit, and also one of the four widely grown crops in world, which has the higher economic value. However, banana is apt to suffer low-temperature injury for its physiologic characteristics and climate characteristics of southern China, resulting in huge economic losses. Thus it is an urgent need to study the mechanism of banana chilling injury, and provided a reference to understand the climatic characteristics of the banana-producing areas, and explore the cold protection cultivating techniques, and reduce the loss of cold damage, and expand the cultivating area. Therefore, this experiment, it expect to achieve the aim to understanding of the physiological changes of banana cold damage, the meteorological factors on banana cold damage as well as explore the cold cultivating mode, through the study of the symptoms of banana seedlings chilling injury under series of low tempreture, the cold protection cultivating techniques and the meteorological data of main years in Guangxi. The results are as follows:1. Under the influence of low temperature stress in banana seedlings, as the temperature decreases, the main physiologicol indices showed different variations, including the relative conductivity rising continuously, soluble protein, SOD and H2O2showing increased decreased trend, MDA, and GSH and proline showing low-high-low trend. The maximum value of all the physiological indexes showing temperature is SOD (6℃)> H2O2(5℃)> MDA and GSH (4℃)> proline (3℃)>soluble protein (2℃). Therefore, SOD and H2O2can be used as a reference standard for evaluation the chilling injury due to their sensitivity of low temperature than other physiological indicators. But the physiological indicators of MDA, soluble protein, relative conductivity and GSH etc. can be used as a reference standard for evaluation the cold-tolerance strength of banana seedlings. 2. The weather’s variation of below5.0℃is high frequency, multi-days, large extend of temperature drop down and long persisting days in banana growing areas in Guangxi; the frequency of chilling damage during1961～1995is higher than1999～2008and it mostly occur in October and January of the next year; A decade with lower frequency of chilling damage would appear following a decade with higher frequency of chilling damage, a heavy chilling damage would appear per2to4years.3. The main meteorological factors for the X1(maximum temperature drop range), X2(extreme minimum temperature), X3(≤5℃the total day number), X4(≤5℃number of times) to affect the cold frost damage occurrence of banana, the correlation coefficient between them is significant, and affect banana production ranking:X1> X3> X2>X4. The relationship between all factors and banana yield can use the formula:y=4.38-1.128X1+0.19X2-0.356X3+0.757X4.4. To filter the climatic factor for the division index, the average of the four divisions indicators of cold frost damage level for the grading standards, the main banana-producing areas in Guangxi, the cold frost damage at higher risk is Pubei county, suburban of Nanning city and Longan county, and a lower risk is Beihai city.5. The cold protection cultivating techniques of cut banana caulis and cover plastic film can significantly improve the survival rate, the speed of growth and development and the yield of winter banana sucker, enhanced the ability of cold resistance of banana sucker and adjust fruit maturation; The technology used in plant with height1.5～1.7meter and number of big leaf below15, the optimal cut proportion is1/3. |
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