| چکیده انگلیسی مقاله |
Introduction: Biocontrol of nematode agents in order to decrease the hazardous impacts of chemical pesticide application including problems of public health and environmental pollution is apriority. In this study, solid (Vermicompost) and liquid products (Liquid Vermicompost, Vermiwash and Coelomic fluid)of the earthworm species Eisenia fetida were tested against root-knot nematode, Meloidogyne javanica in greenhouse conditions. Materials and Methods: In this study, Solid (Vermicompost) and Liquid products(Wormtea, Vermiwash, Coelomic fluid) erthworms (Eisenia foetida) were tested against Meloidogyne javanica and also the effect of Vermicompost was evaluated on Pathogenicity of various nematode initial inoculum in two stage greenhouse conditions. Earthworm-based products (Vermicompost, Wormtea, Vermiwash and Coelomic fluid) were added to tomato pots. Various treatments of liquid as well as solid products and their combination were used in the greenhouse trial. The first Stage greenhouse experiment- Tomato seeds grown in 2 kg sterilized soil. In the treatments having Vermicompost, pots incorporated with 200 gr of this compost homogeneously mixed with soil. After plants reached at two leaf stage, to study the effects of liquid products (Wormtea, Vermiwash, and Coelomic fluid) they added to the pots (500cc) along with the irrigation water every week and after of 4 leaf stage, 5000 nematode eggs and larva inoculated to the tomato host plants. 90 days after nematode inoculation, plant and nematode growth indices separately measured and compared. The experiment conducted based on completely randomized design having four replicates. The second stage greenhouse experiment- Tomato seeds grown in 2 kg sterilized soil. In the treatments, pots incorporated with 200 gr of this compost homogeneously mixed with soil. After of 4 leaf stage, 0,1000,2000,4000 and 10000 nematode eggs and larva inoculated to the tomato host plants. 90 days after nematode inoculation, plant and nematode growth indices separately measured and compared. Results and Discussion: The aim of the present investigation is to explore the impact of earthworm’s (Eisenia fetida) solid (Vermicompost) and liquid (liquid Vermicompost, Vermiwash, and Coelomic fluid) products on the root-knot nematode, Meloidogyne javanica under greenhouse conditions infecting tomato. The first Stage greenhouse experiment -The root-knot nematode indices as well as plant growth parameters recorded. Results showed that all products could reduce the root-knot index, number of juveniles and gall index in greenhouse conditions. The best combination for controlling disease was Wormtea100% and the highest rates of growth is related to plants were treated with Vermicompost + Vermiwash10%. Effects of Vermicompost on the Pathogenicity of various nematode initial inoculum showed, Vermicompost treatment caused increase in plant growth and also reduce nematode reproduction. In other words, Vermicompost could reduce the damage of nematodes. It is concluded that earthworm products have a remarkable potential as biocontrol agents against root-knot nematode. The second stage greenhouse experiment- the treatments , that have Vermicompost + nematod, grew more than control (without Vermicompost). That tomatoes Incubated with 10000 nematode Vermicompost grew until end experiment but those treatment without Vermicompost (They had nematode) died at first of this experiment. Conclusions: Treatments with Wormtea while controlling the nematodes in the soil, reduced root infected indices to nematodes like gall and egg no. and gall index in the root and at the same time, tomato growth indices in treatments having Vermiwash get increased which indicated nematode damage on the host plant has been compensated. Its worthy to say that the aim of nematode control is bring the nematode no below the economic threshold and in this context we can conclude that all these products could achieve reducing economic losses in the greenhouse conditions.These products have essential plant growth nutrients as well. Our finding support the effect of earthworm derived products on the plant growth indices by other researchers. According to our results, Vermicompost and Vermiwash resulted remarkable effects on host plant growth indices and on the other hand, integration of Vermicompost with Wormtea reduced nematode population indices in a great extent. About the effects of various earthworm-derived products on the nematodes not sufficient research has been carried out and most of the work is on the effects of VC against the nematodes.It is concluded that earthworm products have a remarkable potential as control agents against root-knot nematode and improving host plant health. In case we integrate these earthworm products, it’s possible to achieve the nutrient supply for the host plant as well as toxin for the nematode and approach for the organic food production. |