Ali1*, M. Matar1 and K. Al-Asass2
(1) Plant Protection Department, Faculty of Agricultural Engineering, Lattakia University, Lattakia, Syria; (2) Plant Protection Department, Faculty of Agricultural Engineering, University of Damascus, Damascus, Syria.
*Email address of the corresponding author: [email protected]
The root-knot nematode, Meloidogyne spp., is one of the most prevalent agricultural pests worldwide. It can infect a wide range of plants from different families and cause significant damage to protected crops. This greenhouse study aimed to evaluate the efficiency of Trichoderma harzianum, Trichoderma koningii, and Funneliformis mosseae in combating root-knot nematodes in greenhouses as compared with the chemical nematicide Oxamyl. On March 27, 2021, cucumber seeds were planted in pots at a rate of two seeds per pot, at 3 cm depth. Ten days after germination, they were thinned into one seedling/pot. The isolated fungi Trichoderma harzianum and Trichoderma koningii were grown on PDA medium in 9 cm Petri dishes, incubated at 25°C, and then loaded onto sterilized barley grains. Barley grains inoculated with the fungus were added to the soil mixture at a rate of 6 g per pot, with the number of biological units for each of them calculated for every 1g of barley grains at the following concentrations: Trichoderma harzianum 215×107 CFU/g and Trichoderma koningii 250×107 CFU/g. In addition, mycorrhizal fungus Funneliformis mosseae was used at the rate of 5 g per pot. Oxamyl treatment was applied at the concentration of 2 g/pot. Artificial inoculation was carried out on seedlings grown in pots at the four true leaves stage, at a rate of 3000 nematode eggs and 2nd stage juveniles/pot. Readings were taken 60 days after planting, which included the number of galls/1 g of roots, the number of egg masses/1 g, and the number of eggs/3 egg masses. The readings also included the number of larvae/100 ml of soil and the % hatching rate. The results obtained indicated that the highest larval mortality rate occurred in the nematicide Oxamyl treatment, with an efficiency of 97.1%, which was superior to all other treatments. The other treatments reduced the number of larvae by 47.9, 46.1, and 39.6% for T. harzianum, T. koningii, and Funneliformis mosseae, respectively. Oxamyl nematicide was also the most effective in reducing the average number of root galls or root-galling severity, with an efficiency of 96.1%, followed by T. harzianum with 22.7%, T. koningii with 18.8%, and Funneliformis mosseae with 12.4%. Moreover, Oxamyl demonstrated excellent performance in reducing the number of egg masses, with an efficiency of 95.7%, while the efficiency of T. harzianum, T. koningii, and Funneliformis mosseae reached 67.4, 63.6 and 51%, respectively. Oxamyl also outperformed all other treatments in reducing the number of eggs, with an efficiency of 97.2%, while it was 82.9, 83.5 and 67.6% for each of the T. harzianum, T. koningii, and Funneliformis mosseae, respectively. Finally, Oxamyl also outperformed all other treatments in reducing the hatching rate to 2.57%, whereas T. harzianum, T. koningii, and Funneliformis mosseae, reduced hatching rate to 23.4%, 24.97%, and 55.6%, respectively.
Meloidogyne spp., Trichoderma harzianum, Trichoderma koningii, Funneliformis mosseae, Oxamyl.
https://doi.org/10.22268/AJPP-001534