Allelopathic Effect Of Leaves Extracts In Different Age's Of Zaosu Pear On Some Intercropping Crops

The research was conducted to study the allelopathic effect of different extract concentrations from different age's leaves of zaosu pear on seedling growth of intercropping vegetables. In order to made a reasonable intercropping of farming systems, and better arrangements for fruit production to provide scientific information. The main results of the experiments are as followed:1. Radicle length of vegetables was promoted by the extract at its lower concentrations but it was inhibited at the higher concentrations. It was found that the higher the concentration, the more severe the allelopathic effect is.2. The results of correlation analysis showed that there existed a positive correlation between intercropping crops and different age of zaosu pear by the extraction from distilled water. It was found that the older the tree, the more severe the allelopathic effect is. But by the extraction from methanol, there existed a negative correlation between intercropping crops and different age of zaosu pear. It was found that the younger the tree, the more severe the allelopathic effect is.3. Radicle length of oats was promoted by the extract at its lower concentrations, but it was inhibited at its higher concentrations. It was found that the higher the concentration, the more severe the allelopathic effect is.4. Coleoptile length of oats was promoted by the extract at its lower concentrations, but it was inhibited at its higher concentrations. It was found that the higher the concentration, the more severe the allelopathic effect is.5. The effect from extracting of zaosu pear on radicle length of oats was as the same with vegetables. The quantity of radicle of oats was the most when extracting was diluted 100 fold.6. The influence of extracting by undiluted extract on different variety of wild oats as follows: the extracting from the leaf of Zaosu pear in 1996 has the weakest inhibition to Kanyou 3, which was suitable for growing in Zaosu pear field of 1996. The extracting from the leaf of Zaosu pear in 2004 has the weakest inhibition to Baiyan 5, which was optimum to grow in Zaosu pear field of 2004. The extracting from the leaf of Zaosu pear in 2001 has the weakest inhibition to Baiyan 5 which was optimum to grow in Zaosu pear field of 2001. The extracting from the leaf of Zaosu pear in 2002 has the weakest inhibition to Baiyan 5 which was optimum to grow in Zaosu pear field of 2002.