Development And Component Analysis On Fruits Of Energy Plants Quercus Variabilis And Quercus Wutaishanica

Quercus variabilis and Q. wutaishanica, two species of Fagaceae, both have a wild geographic distribution. These two species are dominant species in community of deciduous broad-leaved forests. In addition, starch is the main components of their fruit and the content is high. As woody energy plants, Q. variabilis and Q. wutaishanica have a great prospect of development and utilization. This study sampled the female flowers and fruits of Q. variabilis and Q. wutaishanica, to study the course of fruit development in the growing season. We explored a method for extracting tannins of fruit, and used the spectrophotometer determination and weighing method to measure the content changes of starch and tannic in the process of their development. The results are as follows:1. In the first year, the female flowers of Q. variabilis went through a short development after the pollination in May and then entered the dormancy in early June. In the rest of growing season, the flowers remained stationary. In addition, the ovary at the base of the style continued growing over time. The female flowers broke the dormancy and recovered growth in the early May of the second year. The internal structure of fruit formed in the middle of July and the ripe fruit formed at the end of August.2. The morphology and structure change in the development process of both species were the same according to the present investigation. However, the periods of development were different. The female flowers of Q. wutaishanica did not have dormant period, and the time of development late about half a mouth compared with the Q. variabilis.3. In our study, we took water as the extracting agent and got that the temperature of extraction was detected to be the biggest impact factor on the acorn tannin extraction results. The second factor was found to be solid-liquid ratio. Finally, we reached the conclusion that:the best extraction conditions for the tannin in fruit of both species was solid-liquid ratio1:50, leaching time10h, leaching temperature at60℃。 4. During the development of their fruits, we acquired tannin content of Q. variabilis and Q. wutaishanica at seven periods. The highest content was detected to be mature period, and the tannin content was9.5%and8.9%in the two species, respectively. The percentage gap of tannin was not obvious and the increasing trend was also consistent, in the different periods of fruit ripening.5. The most important period in fruit maturing were found to be at July and August. During this stage, the percentage of starch content was growing fastest. The content of starch of Q. variabilis and Q. wutaishanica reached the maximum of82.3%and71.12%, at the early Steptember. The late ripening, acorn weevil blooms reduced the starch content of the fruit of Q. variabilis and Q. wutaishanica.