EARLY DIAGNOSIS OF BORON DEFICIENCY IN CHESTNUT

Abstract

This study aims to identify an alternative plant tissue to be used in the early diagnosis of boron (B) deficiency in chestnut (Castanea sativa Mill.). A B-deficient orchard was selected, and 16 trees were submitted to two levels of B fertilization. When flowers were in bloom, the following tissues were sampled: leaves, androgynous catkins and flowers. There was a significant increase in B content in plant tissues due to B application. In July, the highest B content was observed in flowers in B0, but leaves had the greatest content in B1. Boron content in the tissues collected in July was positively correlated with B contents in leaves sampled in September. Foliar B concentrations, irrespective of the sampling period, were correlated with chestnut productivity, while the other tissues did not. These results suggest that the leaves, sampled in bloom, were the most efficient tissue for the early diagnosis of B deficiency.

Keywords:

• boron
• chestnut
• foliar analysis

ACKNOWLEDGMENTS

Field assistance was provided by José Rego. Chemical analyze was carried out in the Soil and Plant Laboratory of University of Trás-os-Montes and Alto Douro. This study was supported by grants from CITAB.