Applications in sustainable production

Abstract

Capsicum plants grown under controlled conditions underwent crossed fertilization with N (four levels) and K (three levels) totalling 12 combination of NK dosages. The plants were sampled throughout their growth cycle and the leaves were analyzed to measure total and soluble Ca and Mg, and their fractions. Soluble Mg showed its lowest leaf level in the treatment N4K3, whereas the highest value was obtained at N1K3. Total Mg has the maximum leaf levels at N1K2, whereas the lowest levels occurred in the treatment N2K1. The various fractions of Mg showed different degrees of importance and in the present study the order of importance was: Pectate‐Mg<Residual‐Mg<Organic acid anion‐Mg<Organic anion‐Mg<Chlorophyll‐Mg. Soluble Ca showed its lowest leaf level in the treatment N3K3, whereas the highest value was obtained at N4K1. Total Ca has the maximum leaf levels at N4K3, whereas the lowest levels occurred in the treatment N1K2. The increasing NK supply directly or indirectly affects the integration of the ionic forms of Ca in plant tissues as Ca was integrated in proportions which indicated the growing conditions of the crop, with the following order: Oxalate‐Ca > Inorganic‐Ca > Pectate‐Ca ≈ Residual‐Ca > Phosphate‐Ca