Study On The Metabolism Of Carbohydrate And Endogenous Polyamines During Flower Bud Differentiation Of Macadamia Integrifolia

. This paper studies the flower bud differentiation of two main Macadamia integrifolia: Own Choice (O.C) and Beaumont (695). In the following parts, the two aspects of the flower bud differentiation will be illustrated: I. Observe and record cases of the climate during the period of flower bud differentiation from 2005/2006 and 2006/2007 in macadamia orchard in South Subtropical Crops Research Institute at Zhanjiang. II. Test the amount of carbohydrate and endogenous polyamines in the branches and leaves during the period of flower bud differentiation.The result were as follows:1. The flower-bud expansion and the appearing flower in 2006/2007 early than 2005/2006 (O.C: 4 days and 7 days ; 695:18 days and 12 days).The temperature during the period of flower bud differentiation (from October to first half of December) in 2005/2006 and 2006/2007 the accumulate hours (AH) from 18℃~20℃were 115.7h and 166.3h respectively, which held a comparatively difference. An initial conclusion that low temperature from 18℃to 20℃is good for flower bud differentiation of Macadamia integrifolia can be made.2. The contents of starch in branches and leaves of different treatments during their flower bud differentiation appeared to be descending and the contents of soluble sugar appeared to be ascending, This indicates that starch maybe shift soluble sugar high content of carbohydrate can promote the flower bud differentiation of Macadamia integrifolia. The contents of glucose and sucrose in branches and leaves of different treatments during their flower bud differentiation appeared to be ascending but the contents of fructose appeared to be descending, This result indicates that high content of glucose and sucrose can promote the flower bud differentiation of Macadamia integrifolia.3. The content of endogenous polyamines in branches and leaves of O.C and 695 during the period of their flower-bud induction was in a low level, but reached the highest point before the expansion of flower bud, and descended gradually after the taking-out of flower spike. This result indicates that high content of endogenous polyamines can promote the flower bud differentiation of Macadamia integrifolia.