Study On Compatibility Of Micrografting Of Kiwifruit Drought-resistant Rootstock

At present,the planting area and yield of Kiwifruit in China rank first in the world.It is an urgent task to develop kiwifruit industry with high quality.The results showed that the rootstock of fruit trees played an important role in early fruit,high yield,quality improvement and resistance improvement of scion varieties.The evaluation of grafting compatibility and vegetative growth of grafted varieties is the premise of further evaluation of drought resistance and other horticultural characters of grafted varieties.The traditional evaluation method of grafting affinity is time-consuming and laborious.Micrografting technology provides an alternative strategy,which is efficient,time-saving and low cost.Therefore,it is of great significance to evaluate the grafting compatibility and nutritional growth of MX-1 rootstock and main scion varieties in production.In this experiment,four varieties(Nongda Yuxiang,Nongda Jinmi,Qihong and Hayward)were used as scion materials,MX-1 and Qinmei as rootstock materials.In order to evaluate the nutritional growth and grafting compatibility of rootstock and scion combination,the survival rate was counted after 4 weeks and the nutritional growth was observed.The results are as follows:(1)The survival rate of micrografting was 83%-99%.Among them,the survival rate of grafting on MX-1 rootstock was the highest(98.9%)and that of grafting on Qinmei rootstock was the lowest(83.3%).But the survival rate of MX-1 as Rootstock in the same scion combination of different rootstocks was significantly higher than that of Qinmei.There was no significant difference in survival rate of different scions of Nongda Yuxiang,Nongda Jinshi,Huihong and Heyward grafted to the rootstock MX-1 in different scion combinations of the same rootstock.(2)The earlier the sprouting time of early scion bud and the formation time of primary root,the higher the survival rate of micrografting.(3)The rootstock and scion varieties have influence on the growth of the above ground part,the formation and growth of the root system of the grafted plant.However,the effect of rootstock on the growth and development of grafted plants was significantly higher than that of scion.(4)The formation of early callus and new cambium cells directly affects the germination of scion bud and the formation of primary root of rootstock,and then promotes the growth of plants after micrografting.(5)The formation time of callus and new cambium cells and the formation time of vascular bundle in 6 rootstock-scion combinations were different.The results of histological observation showed that the grafting compatibility of the six combinations was good.But in the same scion combination of different rootstocks,the compatibility of MX-1 with Nongda Yuxiang and Qihong was better than that of Qinmei with Nongda Yuxiang and Qihong.The compatibility of MX-1 with Nongda Yuxiang,Nongda Jinmi and Qihong in different scion combinations of the same rootstock is better than that of MX-1 with Hayward.