ChileanJAR

A. boron fertilization trial was conducted in a non-irrigated vineyard located in Cauquenes, province of Maule, Chile, from 1966 to 1968.
Six levels of borax (0 - 50 - 100 - 150 - 200 and 250 Kg/ha) were broadcasted yearly (two years consecutively) to Semillon vines 25 years old. Vines were established 180X 1.60 m and conducted in a two wire trellis.
There was not significant effect of fertilizer levels on berry weight and soluble solids.
Yield increase was higher with application of 150 Kg/ha than with 0 and 250 Kg/ha. This was observed only for the second growing season.
Soluble boron concentration in the soil was, in general, increased by applications of borax, this increase was greater after the second application of borax.
The aboye also applies to the boron concentration of petioles and was only noticed in the third foliar sampling period (enveraison) of the 1966-67 growing season.
Bloomtime boron concentration of petioles were over 30 ppm during the two growing seasons. Concentrations were higher in thesecond growing season than in the first. Levels of 200 and 250 Kg/ha borax induced toxicity symptoms on the vines. When borax was over-imposed at the following season toxicity symptoms appeared on plants receiving from 100 to 2,50 Kg/ha borax. Petiole boron concentrations at bloomtime of plants showing toxicity symptoms at the early stages of growth were over 41 ppm of boron during the first growing season and over 69 ppm of boron during the second one.
A significant correlation was found between the boron concentration of the petioles as affected by treatments and sarnpIíng time.