Screening Of Rootstock With High Yield And Quality For Grafting Cultivation Of Pepper ’chunqiujiaoba’(Capsicum Annuum L.)

In order to select the rootstock with high yield and quality in pepper grafting cultivation, the effects of different rootstocks on the growth and development, physiological characteristics, the yield and formation of fruit quality were studied and evaluated systematically by using’Chunqiujiaoba’ as the scion, and’Bianjiao No.l’, ’Xinnuojianjiao’,’Hongla No.7’and’Fengziyun No.1’as the rootstock. The main results were summarized as follows:1. Each survival rate of grafted combinations was higher than 90%, and the difference of survival rate between four treatments was not significant. The plant height and stem diameter of grafted pepper were higher than self-rooted plants, and the effects of different rootstocks on the growth potential of pepper plant had no significant difference apart from’Fengziyun No.1’. The results indicated that four different types rootstock have good graft compatibility with’Chunqiujiaoba’.2. The content of chlorophyll a in leaves of grafted plants was significantly higher than that of self-rooted plants during the whole stage of fructification. The contents of chlorophyll b in leaves of grafted plants with ’Xinnuojianjiao’as stock and contents of leaves of grafted plants of the remaining stocks except’Fengziyun No.1’were significantly higher than those of self-rooted plants. The SPAD value of grafted plant leaves with’Bianjiao No.1’and’Xinnuojianjiao’as stock was significantly increased compared with the self-rooted plants. Grafting with ’Xinnuojianjiao’as rootstock can be significantly enhanced photosynthetic rate, but no obvious change when ’Fengziyun No.1’as rootstock, and photosynthetic rate of grafted plants with the rest two kinds of rootstock as stock were significantly higher than that of self-rooted plants only in the middle and later stage of fructification.3. The relative indexes of root growth of grafted plants had different degrees of improvement compared with the self-rooted plants during the same fruit-bearing stage. With ’Bianjiao No.1’and ’Xinnuojianjiao’as stock, the root growth, total absorption area and active absorption area of pepper were significantly increased. In addition to the ’Fengziyun No.1’, the root activity of grafted plants was significantly increased compared with the self-rooted plants.4. During the same period of development, the antioxidant enzyme activity of grafted pepper leaves had various degrees of improvement compared with the self-rooted plants. The SOD activity in the leaves of the grafted plants was significantly higher than that of the control except plant with ’Fengziyun No.1’ as stock. The POD activity in the leaves of grafted plants with’Bianjiao No.1’and’Hongla No.7’as stock was significantly higher than self-rooted plants, and their CAT activity were significantly enhanced in the middle and later stage of fructification. Grafting can reduce the content of MDA in pepper leaves significantly.’Bianjiao No.l’and ’Xinnuojianjiao’as stock can reduce the relative permeability of plasma membrane of leaves significantly in the later stage of fructification. Grafting can improve the accumulation of osmotic adjustment substances in leaves, and the content of osmotic adjustment substances and osmotic adjustment ability in the leaves of grafted plants with ’Xinnuojianjiao’ as stock was significantly higher self-rooted plants.5. There were no obvious differences on fruit morphogical characters between grafted and self-rooted pepper, such as fruit diameter, fruit shape index and single fruit mass. Compared with the nutritional quality of self-rooted fruits, with’Xinnuojianjiao’ and’Hongla No.7’as the rootstock, the content of capsaicin was significantly increased, the soluble sugar content of fruit was significantly improved by using’Xinnuojianjiao’ and’Fengziyun No.1’as stock, but the contents of vitamin C, soluble protein and free amino acid were significantly decreased in grafted fruits with’Bianjiao No.1’and ’Hongla No.7’as stock. In addition to the above, the differences in the same nutritional quality index between grafted and the self-rooted fruit were not significantly different.6. In comparison with self-root plants, the number of fruit per plant, yield per plant and yield were increased remarkably by using’Bianjiao No.1’ and ’Xinnuojianjiao’as rootstock. And yield of seedlings grafted with’Xinnuojianjiao’ enhanced most significantly, total yields was the highest, which was 3544.39 kg·667m-2. The differences of the yield traits of the remaining two grafted pepper plants were not significant.7. The growth and physiological characters of pepper were evaluated by DTOPSIS method based on grey relational degree, and the combined analysis of the survival rate and yield of grafting was also analyzed. The results indicated that plant growth and physiological characteristics of pepper grafted plants with’Xinnuojianjiao’ as stock increased significantly than control. The findings suggested that’Xinnuojianjiao’ was an ideal type of rootstock for the scion, and had a good prospect of application and extension.