INFLUENCE OF IRRIGATION REGIME ON THE LEAF AREA AND LEAF AREA INDEX OF FRENCH BEAN (PHASEOLUS VULGARIS L.)

Abstract

In field experiments the influence of irrigation regime on leaf area and leaf area index in bean plants are investigated. Cultivar “Strike" was used, which is a highly yield, with cylindrical pods and is intended mainly for the canning industry. Experiments were conducted according to the block method, in four replications and size of experimental plots 17.5 m2, and crop plots - 10 m2 and planting pattern of 50 x 5 cm. The variants are the following: 1. Without irrigation; 2. Optimum irrigation by the maintenance of “pre-irrigation soil moisture” over 80% of the Field Capacity (FC); 3. Irrigation with variant 2, but with 30% reduction of irrigation norm; 4. Irrigation with variant 2, but with 70% reduction of irrigation norm. A close relationship between the irrigation norms and leaf area index (LAI) for the conditions of the experiment is established. This relationship is subject to the equation Y=1-0.609(1-x)1,5, where R2 = 0.981. Relationship has been found between LAI and yield, which is expressed best by the quadratic equation: Y=547.8 x-31.9x2-746.6, at R2 = 0.91. The relationship between the mass of leaves (x) and LA is linear, as in terms of dry mass, it is expressed by the equation LA= 81.95x, with R2 =0.843. In terms of fresh leaf mass equation is: LA=35.073x at R2=0.912.