Title: Grafting Cucumber onto Interspecific Cucurbita Hybrid Rootstocks to Improve Productivity and Control wilt Disease Caused by Fusarium oxysporum f. sp. cucumerinum
Abstract: Commercial cucurbits such as cucumber, melon and watermelon are commonly grafted onto interspecific Cucurbita hybrid rootstocks to increase yield and mange soil-borne diseases.This study conducted in private farm in Qallien district in Kafr El-Sheikh Governorate northern Egypt during the period from 2018 to 2020 to identify local Fusarium wilt-resistant interspecific Cucurbita hybrid rootstocks which provide high grafting compatibility with hybrid cucumber scions.Results revealed that disease severity percentage in all interspecific hybrids (0 to 45%) was significantly lower than susceptible commercial cucumber Junco F1 (73.4%).Seven out of the 20 individual hybrids (A02, B02, D02, F01, G02, H01 and I02) were resistant or highly resistant to Fusarium wilt with a mean disease severity ≤ 25%.Results from the greenhouse trials confirmed high levels of resistance in three interspecific hybrids (G02, H01 and I02) which were used as rootstocks for cucumber Junco F1.Fruit yield parameters were increased significantly in grafted cucumber Junco F1 onto wilt-resistant interspecific hybrids compared to un-grafted cucumber.Highly significant differences in anatomical structure were observed between wilt-resistant interspecific hybrid rootstock H01 and susceptible check Junco F1.Fruit yield parameters of grafted cucumber Junco F1 were negatively correlated with disease severity.The interspecific hybrids evaluated in the present study could be promising rootstocks to increase productivity and manage soil-borne diseases for commercial production of major cucurbits in Egypt.