Study On Grafting Seedling Technology Of Muskmelon

With the continuous expansion of the protected facility cultivation of melon(Cucumis melo L.),the problem of continuous cropping obstacles is becoming more and more obvious.The malignant disease caused by Fusariumwilt(Fusarium oxysporum f.sp.melonis)is one of the most serious soil-borne diseases in melon production,which has caused great losses.Nowadays,the grafting cultivation has become the most effective way for solving this problem.Melon grafting mainly involves two aspects:the rootstocks and the grafting methods.The excellent rootstock should have the same grafting affinity with the melon scion,stable resistance to the Fusarium wilt,normal growth of the grafted seedlings,and no significant effect on the quality of the melon fruit(especially no strange taste).However,from the existing literature reports,it seems that the melon grafting technology has not been completely solved yet.The affinity between different rootstocks and scions,growth of melon plants are not identical.The effects of different grafting methods on survival rate,grafting efficiency and the growth of grafted seedlings is not clarified yet,moreover,the research on melon grafting in Zhejiang Province is still in its infancy.Under these backgrounds,this paper carried out the selection of rootstocks for melon grafting and the research on some grafting techniquesin order to provide technical support for melon grafting in Zhejiang Province,and provide references for overcoming the obstacles of continuous cropping of melon.The main results of this study are as follows:1.Four main melon cultivations in Zhejiang Province were used as scions,seven pumpkin cultivations and two melon cultivations were used as rootstocks for grafting.Comparing the traits after grafting,such as the grafting affinity(survival rate and growth of grafted seedlings),the disease resistance of rootstock,the flowering and fruit quality after grafting and so on.The results showed that there were significant differences in the resistance to Fusarium in several rootstocks,among which pumpkin rootstock'Sizhuang No.10' showed high resistance,melon rootstock'Yongzhen No.9'and pumpkin rootstock'cold-resistant melon rootstock 606'showed resistance,'Japanese XueSong','102103'and'heat-resistant melon rootstock 60^7'showed medium resistance,the other rootstocks showed susceptible.The average survival rate of all grafted combination was above 75%,among them,the survival rate of melon rootstock'Yongzhen No.9'and'Tengmi No.6',pumpkin'Sizhuang No.8'and'Sizhuang No.10'grafting with four types of scion were all above 91%.There were significant differences in flowering time between different grafting combinations,and grafting tended to delay flowering,especially when pumpkins were used as rootstocks.In addition,the grafting had a significant effect on the quality of melon fruit.The average fruit weight of most grafting combinations was lower than that of self-rooted seedlings;the centersoluble solid of most grafted combinations were higher than those of self-rooted seedlings,but the difference was not significant.After tasting the fruit,it was found that the fruit of the pumpkin rootstocks had strange taste,especially when'Yugu'grafted with four pumpkin rootstocks.Synthesize the performance of all above traits,'Yongzhen No.9'and'Sizhuang No.10'may be selected as rootstocks of'Dongfangmi No.l'and'Xizhoumi No.25';'Yongzhen No.9'may be selected as rootstock of'Yugu','Mijiangnan 401'may choose'Sizhuang 10' as rootstock.2.There were significant differences in grafting efficiency among different grafting methods.The pumpkin rootstock'Sizhuang No.10' was grafted with'Dongfangmi No.1'to study the effects of different grafting methods on grafting efficiency,seedling growth and fruit quality.It was found that the grafting rate(275.42 plants/h)of cut-grafting was the highest,but had a poor survival rate(93.29%).The survival rate(97.28%)of both-root-cut grafting was higher,but its grafting rate was low(182.69 plants/h).The grafting rate(259.68 plants/h)and survival rate(98.00%)of insert-grafting were both higher.Moreover,different grafting methods had no significant effect on field traits and fruit quality.Therefore,when using pumpkin as rootstocks to graft the melon,insert-grafting is a more ideal method.3.Due to the long hypocotyl of rootstocks is not conducive to the grafting operation,we treated with melon rootstock('Yongzhen No.9')and pumpkin rootstock('Sizhuang No.8')with paclobutrazol.It was found that different concentrations of paclobutrazol significantly inhibited the elongation of hypocotyl of rootstocks,and the stem diameter and cotyledon growth of seedlings were also inhibited to some extent.However,there were no significant differences in growth of seedlings,flowering,yield and fruit quality of different concentrations of paclobutrazol.Therefore,paclobutrazol treatment can be used in the production of melon grafted seedlings to improve the grafting efficiency and seedling quality.Among them,the suitable concentration of paclobutrazol in melon rootstocks is 1.5?2.5 ppm,and the suitable treatment concentration of pumpkin rootstocks is 4?8 ppm.