Preliminary Study On Biology Mechanism Of Grafting Early In Cucumber

Using black seed pumpkin as root stock,and cucumber cultivar Jinyou 4 as scions, grafting was made to compare the differences anatomical form and structure,activities of membrane protective enzymes,stem IAA,GA and ABA contents and stem soluble protein components between grafted and self-root cucumber,and physiological mechanism of grafting superiority was discussed.The result showed as following:1 The cucumber grafted processes included the emergence of septum,the formation and docking of calli,the formation of vascular bridges,and the differentiation and connection of conduction tissues.After grafted,the septum appeared on cross-section at the 1st-3rd day;the calli set up and both the sides of calli began to contact each other and the septum was disappeared gradually at the 5^th-6^thday;the calli began to set up and vascular bridges set up at the 7^th-8^thday;vascular tissues began to set up and contact each other at the 11^thday,then the whole reunion process was over.2 The activity of SOD,POD,CAT in the grafting the cucumber have always been higher than that of self-root cucumber.It illustrated that it has strong activity of membrane protective enzymes and stronger ability of resistance membrane lipid peroxidation to maintain its strong growth.3 The soluable protein contents of self-root cucumber and self-root were basically higher than those of healing grafting,and decreased with the growing days.The content of soluble protein was decreased firstly and then increased in early days of grafting.4 The content of IAA,ABA and GA at various measuring stages of grafted cucumber were significantly different from those of self-root cucumber.The content of IAA,ABA was increased firstly and then decreased,and its contents reached to maximum at the 4th day and 5th day,and the content of GA was decreased firstly and then increased,it reached to minimum at the 6^thday.Since the IAA self-root Cucumber was always higher than in the healing of the graft,while the ABA is in the opposition,it reached to minimum at the 4^thday.5.Through three hormone NAA,6-BA,KT deal with the grafted seedlings,the grafted cucumber were in the best treatment at 1.5 mg / L concentration of grafting,while 6-BA is the best in three hormones.It can improve the grafting survival rate by the appropriate combination of hormone and grafting extracts treatment cucumber scion.