Effect of soil boron application on flower bud and leaf boron concentrations of olives.

摘要

Field studies were conducted in Portugal to determine the effect of soil boron (B) application on flower bud and leaf mineral composition of olives. For the first experiment, 10 pairs of olive trees were chosen from 10 different olive orchards, half being the cultivar Santulhana and the other was the cultivar Madural. On each pair, one tree was B-fertilized (+B) on 29 March 2003 with 8.3 g of B (as Borax, 11% B) and the other pair kept as control (-B). On the second experiment, 3 trees per treatment of cv. Cobrancosa were subjected to soil application of 0, 2.8, 5.5, 11.0 and 22.0 g B/tree. Flower bud samples were taken on 24 May 2003 and leaf samples on 12 July 2003 and 31 January 2004. In experiment 1, soil B applications increased B content on flower buds. However, the differences were statistically significant only when the 10 pairs of trees (both cultivars) were jointly analysed. Mean flower bud B contents rose from 22.3 to 24.5 mg/kg. Soil B application also increased leaf B content in July 2003 and January 2004. In experiment 2, soil B application significantly increased flower bud and leaf B contents. Tissue B contents ranged from 11.4 to 20.2, 15.5 to 21.0 and 14.0 to 16.5 mg/kg in flower buds and leaves on Jul. 03 and Jan. 04, respectively. Soil B applications did neither influence the N, P, K, Ca and Mg content of tissues in experiments one nor 2. Flower buds seemed to have had access to the recently soil applied B. Leaves and flower buds developing simultaneously seemed to be concurrent sinks for recently uptaken B. Early spring soil B application was effective to supply the B requirements of flower buds and leaves during anthesis.