Meloidogyne incognita is an intra-plant parasite that lives in the soil and is a widely affected group of plant parasitic nematodes. In heavily infected fields, root-knot nematodes can reduce crop yields by up to 75%. Nematodes invade the roots of plants with the help of stigma and are able to migrate from cell to cell, looking for suitable foraging sites to develop, where they form giant cells known as galls or knots. Highly toxic pesticides and soil fumigation are commonly used in production to solve such problems. In recent years, biological control methods and biotechnology methods have been widely studied and applied in the management of plant parasitic nematode diseases. Purpureocillium lilacinum has biological control effects on a variety of plant pathogens, especially plant nematodes. This fungus occurs naturally in the soil and rhizomes of many crops and can grow over a wide range of temperatures (8-38) and pH tolerance. The researchers systematically evaluated the protective effect of Lavender lavender on root-knot nematode disease.
The researchers directly exposed root-knot nematodes to Lavender lavender to observe its inhibitory effect on egg hatching and larval survival of root-knot nematodes. It was found that Lavender had high inhibitory activity against root-knot nematodes, and the inhibitory effect was more obvious with the increase of exposure time and concentration. Under the standard concentration (10 g hyphae and 100ml of water), the inhibition of egg hatching was the highest, which was 628%。After 48 h, the hatchability of nematode eggs decreased compared with the control treatment at 5-fold, 10-fold, 20-fold and 50-fold dilutions of the standard concentration. 7% and 179%。However, the effect of Lavispora lavender on nematode viability was found to have the highest mortality rate of 61% in the standard concentration suspension, and only 31% in the 50-fold dilution, indicating that the larval mortality rate was greatly affected by the fungal inoculation concentration.
To further observe how Lavender lavender infiltrates and infects nematode eggs and larvae. The parasitism of the eggs was recorded after 10 days of fungal treatment, and the presence of hyphae or spores inside or outside the eggs was the criterion. It was observed that Lavender lavender could successfully penetrate the eggs that had not yet hatched, and the probability of parasitism of nematode eggs was close to 100% after 10 days of treatment. In addition, fungal hyphae interact directly with larvae, significantly reducing the survival rate of larvae.
It was proved that inoculation with nematodes significantly inhibited the normal growth of eggplant, such as a decrease in plant height197%, fresh weight reduced by 238%。Compared with the uninoculated plants, the plant biomass was significantly reduced after inoculation with nematodes, and the stem dry weight and root dry weight were reduced by 12., respectively2% and 91%。In contrast, the application of Lavender lavender reduced the adverse effects of nematode infection, and further increased the growth height and biomass of plants, and the contents of chlorophyll and carotenoids in the leaves of eggplant inoculated with Lavender lavender were also significantly increased. These results suggest that Lavender can be used for the control of nematode disease and the function of promoting plant growth. Finally, it was found that the application of Lavender lavender could reduce the number of galls and nematodes in the field by 62% and 52%, respectively. Cross-section of eggplant roots shows that fewer female root-knot nematodes are observed when lavender viophora is pre-inoculated onto eggplant roots. In summary, Lavender can act as an effective nematicide to protect eggplants from root-knot nematodes.
Fig.1 Directly effect of Lavender lavender on root-knot nematode eggs and larvae.
Fig.2 Lavender liva alleviates the damage of root-knot nematodes to root tissue.
This study evaluated the control effect of Lavenobacter lavenurum on root-knot nematodes infected with eggplant, and proved that Lavendera lavender has a dose-dependent effect in the control of root-knot nematodes. At the same time, the experimental results also proved that in the case of **worm infection, Lavender can still significantly increase plant biomass and change the photosynthetic conditions of plants. In addition, a large number of studies have proved that Lavender viophyllum has a good biological control effect on pests such as cotton aphid, thrips, greenhouse red spider, greenhouse white fly, and leafcutter ant. With the deepening of research, the fungus has been evaluated as a biological control agent for plant fungi such as Sclerotinia sclerotinia, R. dahlia, Phytophthora capsicum, pathogenic fungi, etc., and these studies have shown that Lavender is a kind of biological control microorganism for plant diseases and insect pests with great application prospects.