Boron tolerance in rootstock and varieties of Vitis genus

Abstract

In the province of San Juan (Argentina), the area of the Jáchal river presents a high potential for the production of grapes used for high quality wines. However, the presence of high Boron (B) content in the irrigation water may limit the expansion of sensitive crops such as vine. In this work, 8 genotypes (rootstocks and varieties) of the genus Vitis were evaluated in order to select the most tolerant types to toxic levels of B. Trials were conducted using plants of one year of age, which were placed in nursery pots under semi-controlled conditions. Plants were irrigated for 60 days with two treatments: Control (nutrient solution) and Boron (nutrient solution + 2ppm B). Boron content in the pots was monitored twice a week and growth parameters (shoot length, growth rate, internode length) and leaf damage (number of total leaves and number of leaves damaged) were evaluated in the plants. Cell damage indicators as Malondialdehyde (MDA) and relative electrical conductivity (CER) were also determined. At the end of the evaluation period, B levels were quantified in root, stem and leaf tissue. The excess of B affected the growth of all the genotypes, reducing significantly the growth rate, the length of bud and the length of the internodes. There was also a progressive increase in the percentage of leaf damage. MDA leaf content was different among genotypes. The content of B in leaf tissue was ten times greater than in root and stem tissues, with differences among genotypes. A positive relation between the contents of B in the different tissues and the percentage of leaf damage was observed.