EVALUATION OF SOME CUCURBITACEOUS ROOTSTOCKS 2-EFFECT OF CUCUMBER GRAFTING USING SOME ROOTSTOCKS ON GROWTH, YIELD AND ITS RELATION WITH ROOT-KNOT NEMATODE MELOIDOGYNE INCOGNITA AND FUSARIUM WILT, INFECTION

Abstract

Grafting onto specific rootstocks provides resistance to soil borne disease and nematodes. Fusarium wilt disease caused by Fusarium oxysporum (FO) as well as root-knot nematode caused by Meloidogyne incognita (RKN) are the most serious soil pathogens in cucumber soil in open fields and under plastic houses. The present study aimed at selecting four cucurbit rootstocks for their resistance and or susceptibility to fusarium wilt fungus (FO) and root-knot nematode (RKN) in two successive years (2010 and 2011) in 10 cm-diam. pots under screen house and in naturally infested soil under plastic house conditions. These selective cucurbit rootstocks were Bottle gourd (Lagenaria sicenaria ) and Winter squash ( Cucurbita maxima)in autumn season and Wax melon ( Benincasa hispida) and Ercola,(C.maxima C.moshata) as hybrid 6001 in spring season. Cucumber scion was Hesham F1 hybrid and Sinai were grafted onto rootstocks in autumn and spring seasons respectively Results indicate that in autumn and spring seasons, the cucumber plants grafted onto Bottle gourd, Lagenaria sicenaria, Winter squash, Cucurbita maxima, Wax melon, Benincasa hispida and C.maxima × C.moshata Ercole hybrid F1 No. 6001 rootstocks grown in pots had highly significantly less root galling, number of females and egg-masses than non-grafted cucumber. Data generally indicated that, Cucurbita maxima were highly resistant and resistant to M. incognita in soil infested with nematode only and or fungus, respectively. Lagenaria sicenaria was moderately resistant to root-knot nematode in both cases. On the other hand, cucumber seedlings grafted onto rootstocks, Lagenaria sicenaria or Cucurbita maxima grown in pots were highly resistant to (RKN) in soil infested with nematode only and or fungus (FO). Non-grafted cucumber seedlings var. Hesham and Sinai were rated as susceptible and highly susceptible to nematode infection in autumn and spring seasons respectively. In spring season, Benincasa hispida and C.maxima × C.moshata Ercole hybrid F1 No. 6001 were moderately resistant (MR) to infection by M. incognita when soil inoculated by nematode only and or Fusarium oxysporum in pot experiment. In autumn season, grafted and non-grafted plants were rated as resistant (R) and highly resistant (HR) to wilt fungus, Fusarium oxysporum (FO) in soihighly susceptible (HS) in pots inoculated by wilt fungus (FO) only and or RKN, respectively. Also, in spring, all grafted and non-grafted plants were rated as highly resistant (HR) to wilt fungus, Fusarium oxysporum (FO) compared to cucumber scion, Cucumis sativus var. Sinai hybrid which rated as highly susceptible (HS) in pots in both cases inoculated by wilt fungus (FO) only and or nematode (RKN). Data indicated also that both pathogens significantly decreased the plant criteria (Shoot and root weight, and shoot and root length), when they were inoculated by RKN or and fusarium fungus (FO) compared to un-inoculated control. Also, the inoculation with root-knot nematode (RKN) alone decreased the plant criteria than inoculation with Fusarium and nematodes. In natural infested soil experiments in both seasons, data was completely similar the data recorded in pots. Plant shoot growth characteristics; cucumber yields (no of fruits per plant and total fruits per plant and yield in one meter square), Cucumber fruit characteristics, and chlorophyll contents were significantly improved in plant leaves compared with scion cucumber. Consequently, the shoot macro-elements were increased compared with scion cucumber.l infested with fusarium wilt (FO) only and or nematode (RKN). Cucumber scion, Cucumis sativus var. Hesham F1 hybrid which rated as susceptible (S) and