Rootstock/scion in dwarf cashew improves aluminum tolerance

Abstract

The use of cashew (Anacardium occidentale L.) genotypes tolerant to aluminum may be a strategy to increase crop production in regions with predominance of acid-reactive soils, low nutrient availability and high concentrations of exchangeable aluminum. The objective of this study was to verify the effect of interaction rootstock and scion of dwarf cashew genotypes and aluminum tolerance. An experiment was performed with dwarf cashew grafted seedlings, three genotypes were evaluated as rootstock ('CCP 06', 'CCP 09' and 'CCP 76') and three as scion ('CCP 76', 'Embrapa 51' and 'BRS 226'). Plants were grown in the absence and presence of aluminum (30 mg L−1 Al) in a nutrient solution with six replications. One hundred and ten days after the beginning of aluminum exposure, plants were evaluated for biometric parameters and aluminum accumulation in the stem, leaves and roots. The largest accumulation of aluminum in dwarf cashew plants occurred in the roots, but a lower accumulation in stems and leaves. The use of the dwarf cashew genotype 'CCP 09' as rootstock and the 'CCP 76' and 'Embrapa 51' as scion, resulted in grafted seedlings with greater tolerance to aluminum.