EFFECT OF SHELTER TREES ON GROWTH AND YIELD OF PECHAI (BRASSICA CHINENSIS L.), MUNGBEAN (VIGNA-RADIATA L.) AND MAIZE (ZEA-MAYS L.)

Field experiments were conducted to determine how shading by shelter t rees would influence shoot growth and yield of pechai (Brassica chinen sis L.), mungbean (Vigna radiata L., cv. Fag asa 7) and maize (Zea may s L., cv. IPB var.1). Before sowing of crops, 3 treatments consisting of different relative light intensities (RLI; 100, 88.7 and 24.9%) wer e prepared without and with the use of shelter trees differing in dens ity in a field at Bayog in Los Banos, the Philippines. Values of leaf number, leaf area, chlorophyll content, shoot dry matter and yield of the 3 crops at 24.9% RLI were significantly lower than those at 100 an d 88.7% RLI. Values of specific leaf area (SLA) of the crops, on the o ther hand, increased significantly at 24.9% RLI. It was observed that there was a difference in yield components between mungbean and maize at 24.9% RLI. Yield of mungbean decreased due to the decrease in the p od number but not in the grain number per pod and grain weight, while that of maize decreased due to the decrease in both kernel number and kernel weight, suggesting that fertilization in maize was more affecte d by shading than in mungbean. In conclusion, solar radiation is neces sary for proper growth and higher yield of crops intercropped with tre es. It was suggested that mungbean became better adapted to shading th an maize in terms of yield.