Effect of Mulching Manures and Use of Heterorhabditis Bacteriophora on Strawberry Fruit Yield Temnorhynchus baal and Meloidogyne javanica Under Field Conditions

Abd-Elgawad, M.M.M., L.W. Duncan, M.M.A. Hammam, F. El-Borai and I.E. Shehata. 2024. Effect of Mulching Manures and Use of Heterorhabditis Bacteriophora on Strawberry Fruit Yield Temnorhynchus baal and Meloidogyne javanica Under Field Conditions. Arab Journal of Plant Protection, 42(3): 306-317. https://doi.org/10.22268/AJPP-001262 The importance of safe methods to manage strawberry pests has become more evident with increasing strawberry production and export in Egypt. Root damage by white grubs (Temnorhynchus baal larvae) and root-knot nematode (RKN), Meloidogyne javanica cause severe losses to strawberry fruit yield. Growers often rely on a few selective chemical pesticides to control these pests and to minimize pesticide residues in order to comply with maximum residue limits allowed for fruit export. Entomopathogenic nematodes (EPNs) that invade and kill grubs and reduce RKN population levels in the soil may be as effective as these insecticides in some cases. We evaluated the profitability of mulching strawberry with commonly used cow and/or chicken manure, with and without application of commercial Heterorhabditis bacteriophora in two farms for four consecutive years. All plots received chemical fertilizers. The designed drip irrigation system for EPN delivery in the farms insured efficient and even (P < 0.05) application of EPN in all treatments. Timing of EPN application varied due to import regulatory guidelines. All manure mulch treatments increased strawberry yield each year at a farm in Al-Qalyubia governorate, whereas yield remarkably increased in the fourth season at the farm in El-Beheira governorate. Compared to EPN-treated plots, 70% more (P = 0.06) insects were recovered in soil beneath dead plants in plots that did not receive EPNs. Heterorhabditis bacteriophora boosted fruit yield (P < 0.05) in the second and fourth years at El-Beheira and in all years at Al-Qalyubia. It reduced (P < 0.05) numbers of Meloidogyne javanica galls/egg masses on strawberry roots and juveniles in the soil in both farms. Mulches had no measurable effect on EPN performance, but suppressed pests and boosted plant productivity. The greatest yield enhancement by EPN occurred in the second year at El-Beheira farm when EPNs were applied shortly after planting (October), enabling early season control of the pests, but in the third year at Al-Qalyubia farm where the weather was generally warmer than that at El-Beheira, and therefore more suitable for EPN activity. Keywords: Strawberry yield, entomopathogenic nematodes, Meloidogyne, mulching, Egypt.