Effect of inoculum levels of Rhizoctonia solani and Meloidogyne incognita on chile pepper in soil simultaneously infested withboth pathogens

摘要

Meloidogyne incognita and Rhizoctonia solani have been isolated from chile fields in New Mexico. Our hypothesis investigated whether inoculum level of R. solani and M. incognita had a synergistic effect on chile injury in greenhouse experiments. Nematodes were inoculated at rates of 200 and 2,000 second juveniles (J2) per plant and fungi was inoculated at rates of five and 10 R. solani agar pellets (each 1-cm in diameter) for low and high level of inocula, respectively. Plant growth measurements wererecorded three months after inoculation. The frequency of recovery of R. solani from tap roots and stem segments, M. incognita egg counts and reproduction factor were measured at the termination of each experiment. Generally, there were slight evidencesfor the effects of inoculum level on the interaction of R. solani and M. incognita. Changes in reproduction factor for M. incognita were detected in the presence of R. solani at different inoculum levels. Frequencies of R. solani were slightly affectedby M. incognita inoculum levels. Chile growth parameters were not affected by the interaction between the two pathogens regardless of inoculum levels. Thus, sporadic influence of inocula level on the inoculation of R. solani and M. incognita was detectedoccasionally.