Manejo integrado del nematodo del nudo radical [Meloidogyne incognita (kofoid & white) chitwood y Meloidogyne mayagiiensis rammh & hirschmann] en almacigos de guayabo (Psidiumguajava linneo), variedad Palmira ICA-1

Abstract

Purpureocillium lilacinum strain PL-11 and Pochonia chlamydosporia strain JL-1 fungi are opponent to plant parasitic nematodes. The objective of this research was to know the effect of P. lilacinum, strain Pl-11 and P. chlamydosporia var. catenulata, strain Jl-1, on Meloidogyne incognita and Meloidogyne mayaguensis in guava roots from the Palmira ICA-1 variety and their relationship with plant growth. In a seedling nursery, located in the Montelindo farm of Universidad de Caldas, 12 groups of 18 thirty (30) days old seedlings of guava, Pamira ICA-1 variety, were stablished under a completely randomized design. Roots of 18 seedlings were inoculated with 5,000 eggs and second (J2) stage juveniles of M. incognita and M. mayaguensis/seedling. Eight days before and after inoculation of both Meloidogyne species and 30 and 60 days later, 111 mL of P. lilacinum (1 × 109 espores/mL)/seedling was added. The same process was made with P. chlamydosporia (1 × 109 esporas/mL), the mixture of P. lilacinum and P. chlamydosporia (1 × 108 espores/mL), the mixture of P. lilacinum and P. chlamydosporia (1 × 106 espores/mL) in combination with Carbofuran (125 ppm and 500 ppm). There was both nematode and water control. It was demostrated that seedlings treated with the mixture of P. lilacinum and P. chlamydosporia (1 × 106 esporas/L) in combination with Carbofuran (125 ppm), and the mixture of P. lilacinum and P. chlamydosporia (1 × 108 esporas/mL), 8 days before and after inoculation of M. incognita and M. mayaguensis and newly treated 30 and 60 days after inoculation of nematodes, obtained a better growth with a height of 62.8 and 59.8 cm, a dry weight of leaves of 24.6 and 21.1 g, and a dry weight of roots of 12 and 11 g, respectively, in comparison to the controls that had lower values with 41.27, 9.93 and 4.58 g, respectively. With the same mixtures, seedlings decreased root knot index in 6 and 4 degrees, respectively, in relation to the nematode controls, which obtained an index of 9. P. lilacinum strain PL-11 and Pochonia chlamydosporia strain JL-1 fungal strains, alone or in mixture, confirmed their excellent infective potential in the control of M. incognita and M. mayaguensis, being possible to use them in nursery conditions as a part of an integrated pest management program of Melodogyne spp.