MALABSORPTION OF MINERAL NUTRIENTS AND EFFECTS OF FOLIAR FERTILIZATION ON CONTINUOUSLY CROPPED CAPSICUM ANNUUM L. VAR. ANNUUM

Abstract

Cayenne pepper (C. annuum var. annuum) cultivar known as line No. 5 was used to establish a reference baseline for fertilization experiments under conditions of continuous cropping versus crop rotation. The effects of continuous cropping on absorption of 11 essential nutrient elements and fruit yield were studied. Concurrently, we also examined the effects of foliar application of urea + KH2PO4 and Fe + B + Zn + Mn on nutrient absorption due to continuous cropping. The results showed that, compared with peppers grown in rotation soil, continuous cropping affected the uptake of eight elements (P, K, Mg, Fe, B, Zn, Mn, Cu) and transport of these elements to the aerial parts of the plant, although the element concentrations in continuous cropping soil were not lower than those in rotation soil. Continuous cropping caused a decline in fruit yield. The impact of continuous cropping on the uptake of trace elements was greater than it was for macro elements. Foliar application of urea + KH2PO4 significantly improved the P, Mg, Fe, and Mo content of continuously-cropped pepper plants, but did not significantly improve the content of N and K, and there was an antagonistic effect on Zn uptake. Foliar application of Fe + B + Zn + Mn, significantly increased the Fe, B, Zn, Mn, and P content in the plants; Ca uptake in the leaves and fruits was promoted to a certain degree, but there was obvious antagonism toward Mo and Cu uptake in the stems, leaves and fruits. Pepper fruit yields were significantly increased by foliar application of urea + KH2PO4 or foliar application of Fe + B + Zn + Mn. However the effects of foliar application of Fe + B + Zn + Mn on increased production were significantly better than the effects of foliar application of urea + KH2 PO4.