Respostas morfofisiológicas de combinações copa/porta-enxertos de citros sob estresse hídrico.

Abstract

The water stress a#ects the growth, the development and the production of fruitful species, among which citrus. The use of combinations scion/rootstock tolerant can guarantee the agribusiness of citrus under such conditions. With the intention of assisting that need, this work had as objective evaluates the growth of four combinations citrus scion/rootstock under water stress vegetation home, constituted of improved materiais obtained by PMG of citrus of CNPMF, in a randomized blocks experimental, with three repetitions, consisting from four leveis of water to the plants, being 50, 75, 100 (testifies) and 125% of Real Evapotranspiration (ETr) and four combinations citrus scion/rootstock. Growth variables, physiologic measures and biomass fomlation were evaluated, being the data submitted to the variance analysis by the test 'F' with studies of regression polynomial. The reduction in the applied sheet committed the growth in number of leaves, rootstocks diameter, grafting and cup; The use of the irrigation affected the fitomassa total drought of the plants, and the largest value (266,02 g for plant) it was obtained with 115% of replacement of Evapotranspiração Reall The application of smaller sheets than 75% of ETr commit, in more than 10%, the gaseous changes and the photosynthesis of the combinations scion/rootstock of studied citrus; The combination between he lemon tree 'l Cravo Santa Cruz' and the grapefruit 'Star Ruby' has growth potential in the semiarid, for there being better physiologic behavior and larger water use efficiency; The water levei of 100% of ETr, better growth of shoots, which can be used as referente for studies of appropriate slides in citrus irrigation in the semiarid. Keywords: genotypes.