Regulation Of Grape Growth By Light Environment And Study On Physiological Characteristics Of Micrografting Healing Process

Micrografting technology is one of the emerging methods of grape breeding,the success of grafting is regulated by a variety of factors such as light,grafting technology,and rootstock relationships.Therefore,clarifying the relationship between the light environment regulation and the rootstock healing during the micrografting process has important theoretical reference significance and promotion role for the establishment of grape tube micrografting system and accelerating grape industry upgrading.In this test,’Zaoheibao’,’Qiuhongbao’,’Jinghongbao’,’Lihongbao’,and ’Wuhecuibao’ grapes are used as test materials,comprehensive comparison of photosynthetic response of grapes under LED supplementary light treatment inside and outside the facility and changes in physiological and biochemical indexes of grape plantlets under seven different light qualities,then select the optimal light quality suitable for micrografting of grape plantlets;Then,use ’Qiuhongbao’,’Jinghongbao’,’Lihongbao’,and ’Wuhecuibao’as test materials,analyze and study the survival,healing and compatibility physiological mechanism of grape micrografted seedlings with different rootstock combinations.In this way,the micrografted tissue culture and rapid propagation system of grapes was optimized and the physiological mechanism of rootstock healing was explored.Investigate the application of micrografting technology to improve the transformation of embryo rescued deformed seedlings,and provide a theoretical basis for the development of grape breeding.The main results are as follows:(1)The content of carotenoids in grape leaves cultivated by LED supplementary light cultivation in the facility is the highest,and the net photosynthetic rate is significantly higher than that of treatment outside the facility.LED supplement light in the facility is more conducive to the photosynthesis of grapes and is a more suitable cultivation mode for grape growth.(2)Compared with monochromatic light,red and blue composite light quality is more conducive to the growth of grape plantlets.Using correlation analysis and principal component analysis,it was concluded that total chlorophyll,leaf length,leaf width,plant height,and antioxidant enzyme activities were the main indicators of light quality affecting the growth of test-tube plantlets in grapes.Then use gray correlation analysis to screen out the ideal light quality of each treatment : Red and blue 5:1 light quality is the ideal light quality for the growth of ’Qiuhongbao’ test tube seedlings;Red,blue and white 3:1:1 light quality is the ideal light quality for the growth of test tube seedlings ’Jinghongbao’ and ’Lihongbao’;Red and blue 4:1 light quality is the ideal light quality for the growth of ’Wuhecuibao’ test tube seedlings.(3)According to the morphological study of the micrografting rootstock healing process,it was found that the healing site of the micrografted seedlings in the early stage of grafting has undergone histomorphological changes from the appearance of callus to close connection,at 7 d,the healing connection was basically started.(4)1/2MS+0.2 mg·L-1 NAA+0.2 mg·L-1 IBA+30.0 g·L-1 sugar+7.0 g·L-1 agar medium(p H 5.8~6.0)as a subculture for grape micrografted seedlings,it can significantly increase the true leaf extraction rate.(5)By studying the physiological mechanism of grafting compatibility of different rootstock combinations,it was found that when using different scion varieties,the survival rate of the grafted seedlings of the ’Wuhecuibao + Qiuhongbao’ combination was the highest,the difference between’Jinghongbao + Qiuhongbao’ was not significant,which was significantly higher than other combinations.When using different scion varieties,the POD and CAT activities of ’Jinghongbao +Qiuhongbao’ combination were higher than those of other combinations;when using different rootstock varieties,the SOD and POD activities of ’Wuhecuibao + Qiuhongbao’ combination were higher than those of other combinations.By analyzing the effect of different scions and rootstocks on the compatibility of grape micrografting seedlings,it is concluded that the two combinations of ’Jinghongbao + Qiuhongbao’and ’Wuhecuibao + Qiuhongbao’ have the highest survival rate and the best compatibility.