Nutrient budgeting and nutrient balance under high density planting system in cashew (Anacardium occidentale)

Abstract

 The study on nutrient budgeting and nutrient balance was conducted to determine the optimal fertilizer requirement
for cashew (Anacardium occidentale L.) under high-density planting system in relation to yield and net profit. The sixyear
old plantation of cashew Bhaskara variety under high-density planting system (625 trees/ha) was used. A negative N,
P and K balance of 113, 22 and 45 kg/ha/year was found in the control plot where no fertilizers were applied. A strong
positive N balance ranged from 137 to 251, P balance from 34 to 75 and K balance from 89 to 164 kg/ha/year were found
in trees with two-thirds and full doses of fertilizer treatments. In treatments with one-third dose of fertilizers, a positive N,
P and K balance of 40, 19 and 40 kg/ha/year were found. This indicates that in high-density planting system, existing
fertilizer schedule, viz. recommended dose of fertilizers (RDF) is on higher side and optimal dose of fertilizer required is
only one-third of the RDF. The yield and net profit in full dose and one-third dose of fertilizer treatments were on par. The
higher yield of 1.47 and 1.41 tonnes/ha/year and a net profit of Rs.40 030 and `Rs 41 274/ha/year were obtained in these two
treatments. The application of one-third dose of fertilizer to soil instead of recommended dose of fertilizer not only helps
to reduce the input required and cost of cultivation but also the ecological hazards arising from excess inorganic fertilizer
application. Hence, one-third dose of fertilizer is optimal for cashew plantation under high-density planting system.