EFFICACY OF PAECILOMYCES-LILACINUS IN SUPPRESSING ROTYLENCHULUS-RENIFORMIS ON TOMATO

Effects of rice-cultured Paecilomyces lilacinus on Rotylenchulus renif ormis were studied in both greenhouse and field microplot tests with ' Rutgers' tomato. Numbers of R. reniformis were reduced (P less than or equal to 0.05) by P. lilacinus, with suppression in the initial green house test ranging from 46 to 48% for two rice + P. lilacinus treatmen ts; the rice-only treatment caused a nonsignificant reduction of 25%. In the second greenhouse test, total R. reniformis numbers were restri cted (P less than or equal to 0.05) by 41% by the rice + P. lilacinus treatment, whereas the rice-only treatment had a slight negative effec t (16% inhibition, NS). Total numbers of R. reniformis were suppressed 59 and 36% at midseason and harvest, respectively, in microplots infe sted with P. lilacinus. The fungus was recovered from egg masses via i solations in the second greenhouse test. Shoot and fruit growth of Rut gers tomato were restricted by R. reniformis in the initial greenhouse test irrespective of P. lilacinus treatment, but this nematode did no t affect fresh shoot weights in the second greenhouse test. The nemato de also limited shoot growth of Rutgers tomato in microplots, and P. l ilacinus suppressed R. reniformis numbers sufficiently to prevent rela ted impairment of shoot and fruit growth. This study indicated that P. lilacinus has detrimental effects on R. reniformis population develop ment under both greenhouse and field microplot conditions.