Nutrient mixture (<em>Calda Viçosa</em>) and the nutrient content and yield of the common bean

Abstract

The objective of the present work was to study the effect of a nutrient mixture (calda Viçosa) on the nutrient content of common bean plants, under field conditions. The treatments evaluated were: 1- calda Viçosa (2g.l^-1 ZnSO₄- 7H₂O + 6g.l^-1 MgSO₄-7H₂O + 5g.l^-1 CuSO₄-5H₂O + 1g.l^-1 H₃BO₃ + 4g.l^-1 KCl + 3,5.l^-1Ca(OH) ₂); 2- calda Viçosa + 0.29g.l^-1 of ammonium molybdate; 3- calda Viçosa without magnesium sulphate; 4- calda Viçosa without zinc sulphate; 5- calda Viçosa without borom; 6- ammonium molybdate 0.29g.l^-1; 7- methylthiophanate + chlorothalonil, and 8- check treatment. The eight treatments, in four replications, were studied in a complete block design experiment. The nutrient mixture was sprayed 28 and 35 days after seed emergency, except for the ammonium molybdate (treatment 6) that was sprayded 28 days after seeds emergency, using a knapsack mistblower, 500 l of nutrient mixture per ha. The treatments with at least 55% increase in yield were: calda Viçosa + Mo, calda Viçosa wthout borum and ammonium molybdate alone. These treatments also had the higher number of pods/plant and the number of seeds per pod. Yield increase between 38% and 48% was obtained with calda Viçosa, calda Viçosa without magnesium sulphate, and calda Viçosa without zinc sulphate. Methylthyphanate + chlorothalonil increased bean yield only 13% and, with the check treatment, had borom and coopper levels below the minimum required for bean plants. Other treatments had borom, coopper, zinc and nitrogen levels within the bean plants requirements.The treatments Calda Viçosa + ammonium molybdate and ammonium molybdade alone had significant levels of nitrogen in leaves