Efecto de sustratos con compost y fertilización nitrogenada sobre la fotosíntesis, precocidad y rendimiento de pimiento (Capsicum annuurn)

Abstract

AbstractJ. De Grazia, P.A. Tittonell, and A. Chiesa. 2007. The effect of substrates with compost and nitro genous fertilization on photosynthesis, precocity and pepper ( Capsicum annuu m ) yield. Cien. Inv. Agr. 34(3): 195-204. Fast-growing seedlings have larger immediate nutrient demands as compared with adult plants. A tray experiment was conducted to evaluate the fertilization of sweet pepper trans plants growing on different substrates [Control (60% Sphagnum peat + 40% perlite), Mix I (45% Sphagnum peat + 30% perlite + 25% farm yard com post), Mix II (30% Sphagnum peat + 20% perlite + 50% farm yard com post), and Commercial (40% com post + Sphagnum peat + perlite + vermiculite)] with weekly applications of nitrogen N at rates of 150 and 300 mg·L -1 , compared to a control without fertilization. Seedlings were transplanted in a randomized, complete block design with four replications. Leaf area and fresh and dry weights of leaves, stems and roots were measured for the transplants; the leaf weight ratio, specifi c leaf area, absolute and relative growth rates, leaf expansion rates, leaf area duration, and net assimilation rate were calculated. Precocity, early yield, and total yield were measured for the fi eld crop. The a pplication of nitro gen had positive effects on most growth parameters of seedlings growing on substrates with compost, promoting increased precocity and yield in the transplanted cro p. Few bene fi ts from nitro gen fertilization were observed for seedlin gs growing on substrates without compost. The main effect of the latter is to improve the effi ciency of capture of the applied nitrogen, due to better water retention and ion-exchange capacity.