SANDY (Citrullus lanatus (Thunb.) Matsum. & Nakai) INJECTED ABOUT DIFFERENT PUMPKIN PORTAINJERTS (Cucurbita maxima x Cucurbita moschata)

The production of vegetables is an important activity in the agricultural sector in Mexico, being watermelon one of the main vegetables. The state of Sonora is the second place in surface. The present study was carried out in order to evaluate the response of watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai) cv. Tri-X 313 grafted onto different squash rootstocks, during the months of December 2005 to May 2006. Four commercial squash (Cucurbita maxima x Cucurbita moschata) rootstocks interspecific hybrids RS1330, RS841, RS888 and RS1313 were evaluated and the respective control without grafting. The results showed that the grafting technique reduces seedling survival, and delays the plant growth in nursery conditions. The rootstocks commercialized for their use in cucurbits did not present significant differences in commercial production and quality of watermelon, proving to be an alternative in soils where the plant has problems to grow in their own root. A lower concentration of nitrates in grafted plants was observed, apparently due to a greater efficiency in the activity of nitrate reductase enzyme which promotes the use of nitrates, being able to reduce nitrogen application. RS1330 rootstock showed a higher concentration of zinc and copper.