Mohammad Reza Moosavi

Root‐knot nematodes ( Meloidogyne ), with their broad host range and ability to challenge plant resistance, represent a significant obstacle to the development of crop production, including eggplant cultivation. In this greenhouse study, the resistance of 26 eggplant varieties to M. javanica was evaluated. The plant seeds were sown in two‐kilogram plastic pots and kept under greenhouse conditions at a temperature of 27°C ± 2°C. The seedlings were inoculated at the four‐leaf stage with 6000 nematode eggs. After 60 days, the plants were harvested, and the indices of plant growth and nematode populations were evaluated. In addition, catalase, peroxidase, and superoxide dismutase activity were measured. For this purpose, the varieties Noorabad and Black Beauty, which are highly sensitive and less sensitive varieties, respectively, were planted in one‐kilogram pots and kept in the greenhouse. The seedlings were inoculated with 3000 nematode eggs at the four‐leaf stage. Root tissue extraction was performed at six time points (0, 5, 9, 13, 17 and 21 days) after inoculation. The results showed that the growth indices of the varieties Faselis and Black Beauty were better compared to the other varieties. The significant changes in enzyme activity observed in the Black Beauty variety in response to infection were considered to be the reason for the lower nematode damage. However, according to the Canto‐Saenz classification, all varieties analyzed were classified as susceptible, as they had a gall index > 2 and a reproduction factor > 1.

Summary: The chlamydospore production of three Pochonia chlamydosporia isolates from two different varieties was evaluated on flaxseed and rice husk, testing their survival on talc, kaolin and maize cob powder. The effect of each formulation in suppressing Meloidogyne javanica on tomato was also investigated in glasshouse trials. For all isolates, the number of chlamydospores produced on flaxseed was about twice that observed on rice husk (i.e., 8 weeks after inoculation, isolate IRAN 1119 C produced 98 × 10⁶ and 50 × 10⁶ chlamydospores on flaxseed and rice husk, respectively). Isolate IRAN 1212 C produced more chlamydospores with longer lifespan compared with the other fungi. IRAN 1212 C on maize cob powder could reduce M. javanica by 95% at a level similar to fluopyram. This prototype formulation had a superior effect in establishing the fungus in the rhizosphere and on roots, suppressing the nematode and increasing plant growth. The three P. chlamydosporia isolates reproduced well on flaxseed and could last longer if formulated on maize cob powder, which appears suitable to produce an effective powdered formulation.

Developing a bionematicide formulation was the aim of this experiment. We evaluated chlamydospore production of three Pochonia chlamydosporia strains on flaxseed and rice-husk, and their survival on talc, kaolin and maize-cobs-powder. The effect of each formulations in suppressing Meloidogyne javanica on tomato was investigated in greenhouse. The number of chlamydospores on flaxseed was about twice more than on rice husk for all strains. IRAN 1212C produced more chlamydospores with longer lifespan compared with the other strains. IRAN 1212C on maize-cobs-powder could control M. javanica by 95% that was similar to fluopyram. This formulation had a superior effect in establishing the fungus in the rizhosphere and on roots, suppressing the nematode and increasing plant growth. Three strains of the fungus reproduced well on flaxseed and could last longer if formulated on maize cobs powder. Therefore, maize cobs powder can be suitable base to produce on effective powdered bionematicide.

Imani S, Moosavi SMR, Zare R, Basirnia T (2021) Optimum substrate and carrier for Purpureocillium lilacinum and its effectiveness against Meloidogyne javanica on tomato. Plant Pathology Science 10(2):50-64. Doi: 10.2982/PPS.10.2.50. Introduction: The soil-borne root-knot nematode (Meloidogyne javanica) causes heavy losses in tomato plants every year. Their management by chemical nematicides is ...

Management of root-knot nematodes (Meloidogyne spp.) is too difficult and is mainly based on chemicals. Synthetic nematicides contaminate the environment and endanger the human health, so scientists have been tried to find a new alternative safe method for nematode control. Activating plant immunity system in integration with biological control seems promising. Here, we tried to control Meloidogyne javanica on tomato plants by simultaneous application of jasmonic acid (JA), as a defence inducer, and Purpureocillium lilacinum (Pl) as a biocontrol agent. A factorial experiment was devised with two main factors each in four levels. The concentration of JA and Pl was 0, 0.5, 1, and 1.5 mM and 0, 10³, 10⁶, and 10⁹ spore ml⁻¹ suspension, respectively. Cadusafos was used as positive control. Tomato growth characteristic as well as nematode reproduction traits were evaluated 8 weeks after being grown in a greenhouse. The data were analysed by a custom response surface regression model. Increase in concentration of main factors led to increase in plant growth and decrease in nematode reproduction. JA at 1.5 mM concentration could control nematode the same as cadusafos regardless to fungus concentration. Simultaneous application of JA and Pl reciprocally increase the effect of each factor. The lowest concentration of P. lilacinum and JA for achieving the compromise best plant growth and lowest nematode reproduction were 1.5 mM JA and 40.51 × 10⁶ conidia of P. lilacinum ml⁻¹ suspension.