Selection of Prunus clonal rootstocks based on nutritional efficiency state

Resumo

Rootstock contributes to increase the absorption and nutrients translocation efficiency. We aimed to select rootstocks according to the nutritional physiological state of the scion cultivar. The experiment was carried out during three periods of leaf collect on the 4-year old peach cv. BRS Libra budded onto 21 rootstocks cultivated in a high density orchard. The following traits were evaluated: xylem water potential, dry leaf mass and chemical leaf nutritional analysis. The collected data were submitted to analysis of variance by the F test and some genetic parameters were estimated. When significant, the means were compared using the Scott-Knott test, at 5% significance. The principal component analysis was performed to verify the interrelationships between the rootstocks and the evaluated traits. The deviation from optimum percentage index was used to select the most nutritional stable rootstock. We observed that rootstock affects the dynamic absorption nutrient parameters in interactions with the scion. The highest foliar levels of P were found in the BRS Libra cultivar when budded onto the rootstocks ʹSanta Rosaʹ, ʹBarrierʹ, ʹTsukuba-1ʹ and ʹRosaflorʹ. The leaf analysis revealed a high variation in the mineral nutritional status among the studied Prunus rootstocks. Most of the mineral macro-elements varied between medium and optimal levels. The rootstocks ʹRigitanoʹ and ʹNemaredʹ showed less nutritional limitation and is recommended for cultivations in high density orchards.