EVALUATION OF HEVEA BRASILIENSIS CLONES AGAINST ABNORMAL LEAF FALL DISEASE CAUSED BYPHYTOPHTHORA SPR

摘要

Twenty five modern clones of rubber (Hevea brasiliensis) were evaluated for tolerance to abnormal leaf fall disease caused by Phytophthora spp.,consecutively for seven years under standard prophylactic spray.Two trials each consisting of 13 clones were included in the evaluation.High leaf retention was noticed in the clone RRII 105 closely followed by RRII 5 while it was poor in RRIM 703,RRIM 600,Haiken 1,PB 280,PB 260 and PB 314.Rainfall was found to be a major predisposing factor influencing the disease development.