Micronutrients in caribean pine. II. Boron and cooper corresponding sufficiency and deficiency internal levels

Abstract

A pot experiment has been conducted in a green house, in Piracicaba, Brazil, in order to determine the effects of B and Cu omission in growth, the corresponding internal levels and the efficiency of that nutrients use for young plants of P. caribaea var. hondurensis, P. caribaea var. bahamensis and P. caribaea var. caribaea. Treatments complete, without boron and without cooper had been employed. Washed sand had been used as substrate, being the plants watered twice a day with the corresponding nutrient solution. After the deficiency symptoms stablishment, the plants had been cut and separated in upper needles, lower needles, branches and roots, dried at 75°C, weighed, ground and analysed for B and Cu concentrations. Upper needles, lower needles, branches and roots mean internal levels of these micronutrients had been obtained in either, complete and deficient treatments. Under deficiency, P. caribaea var. bahamensis was the most efficient variety in boron use and P. caribaea var. caribaea the most efficient variety in cooper use.