| Pruning was important in walnut cultivation and management and could balance nutritional between the various parts of the tree as well as promote the growth of the tree.’Chuanxiang’ walnut was taken as test materials on heilongtan walnut base of Sichuan Meishan in this study. In this study, took the ’Chuanxiang’ walnut as test materials on Heilongtan of Sichuan Meishan. In May 2013 and February 2014,dealed with different pruning intensity respectively, by measuring the changes of growth of its branches, the chlorophyll content of leaves, antioxidant enzyme activity, endogenous hormones and the metabolism of carbon and nitrogen, explored different pruning time and pruning intensity on physiological characteristics of ’Chuanxiang’ walnut. The results showed that:1. Under different pruning intensity, the results showed that:except the extreme intensity pruning, the length and diameter of the’Chuanxiang’walnut was positive correlation with pruning intensity increase. There was a longer length and a greater roughness of walnut branches while the pruning intensity increased. The length and diameter of the ’Chuanxiang’ walnut in heavy pruning intensity were 76.19% and 42.86% higher than contrast respectively in growing season, and 86.49%,55.10% in dormant season.2. Under different pruning intensity, except the extreme intensity pruning, the chlorophyll content of ’Chuanxiang’ walnut increased with the pruning intensity increasing in both growing season and dormant season, and the chlorophyll content of heavy intensity were 35.37% and 47.02% higher than contrast. At the same time, the chlorophyll content of extreme intensity pruning was the lowest in growing season, while after the heavy intensity pruning in dormant season.3. After pruning in growing and dormant period, the activity of SOD,POD and CAT showed different trends at different times. After pruning in growing season, the activity of walnut POD increased at first and then decreased, and reached the highest value at the beginning of July, while the value of heavy pruning was 98.0% higher than the contrast. The activity of SOD showed the "N", reached maximum value in early August. The activity of CAT also showed increased first and then decreased. Comparing the deals from pruning intensity, the activity of three kinds of antioxidant enzyme were expressed as heavy pruning> moderate pruning> light pruning> contrast> extreme heavy pruning. Different with growing season, the activity of POD and CAT decreased slightly while the SOD increased first and then decreased in dormant season. On the whole, the activity of three kinds of antioxidant enzyme showed heavy pruning> extreme heavy pruning> moderate pruning> Light pruning> contrast.4. Under different pruning intensity in growing season, the content of IAA, GA and ZT of heavy pruning were expressed as the highest, and were a significant positive correlation with time shift. On August 5, the content of IAA, GA and ZT under heavy pruning treatment were 122.50%,64.72% and 43.24% higher than the contrast respectively. But the content of ABA has been declining over time, until August, the content of ABA under heavy pruning was 17.39% lower than the contrast. At the same time, the value of (IAA+GA+ZT)/ABA also increased gradually, the heavy pruning is the highest. In dormant season, the content of IAA, GA and ZT rose over time, except the extreme heavy pruning, the heavier the pruning intensity, the higher the content. But the content of ABA was on the contrary. Besides, the value of (IAA+GA+ZT)/ABA got the same performance with growing pruning.5. Under different pruning intensity in growing and dormant season, except the extreme intensity pruning, the content of soluble sugar and starch showed an upward trend, the heavier the intensity of the pruning, the higher content of the soluble sugar and starch, while the content of nitrogen showed a downward trend in general over time, the heavier the pruning strength, the higher the content of nitrogen. The C/N ratio was rising over time, the C/N value is the highest in heavy pruning, followed by extreme intensity pruning.6. From the growth of branches, chlorophyll content, antioxidant enzyme activity, endogenous hormone content and the content of carbon and nitrogen metabolism, Pruning in dormant season performance better than pruning in growing season. At the same time, the content of IAA, GA and ZT, shoot length and diameter, chlorophyll, soluble sugar and starch were higher than pruning in growing season while the content of ABA was on the contrary. So that, pruning in dormant season is the better for ’Chuanxiang’ walnut. |
