Biodiversity and pathogenicity of entomopathogenic fungi associated with the lesser spruce sawfly, Pristiphora abietina

Abstract

Outbreaks of lesser spruce sawfly, Pristiphora abietina (Christ) (Hymenoptera: Tenthredinidae), on conifers regularly occur in Turkey and other European countries. Chemical pesticides have been used to contain outbreaks, but those may damage the forest and disturb natural enemies. To minimize the use of chemical pesticides in the management of this forest pest, we identified the entomopathogenic fungi (EPF) that naturally occur on P. abietina and tested their efficacy against the pest under laboratory and semi‐field conditions. Using morphological and molecular techniques, 13 EPF isolates were obtained from the pest and identified as Beauveria bassiana (Bals.‐Criv.) Vuill., Beauveria pseudobassiana S.A. Rehner & Humber, and Lecanicillium muscarium (Petch.) Zare & W. Gams. A laboratory screening test at 106 conidia ml−1 showed that all isolates caused 59‐100% mortality after 14 days. Further experiments were performed with the three most effective isolates, all belonging to B. bassiana. For these isolates, an increase in conidia dose increased pest mortality. Also, the ability of horizontal transmission in the pest population was shown. All three isolates were effective in killing P. abietina on spruce under semi‐field conditions. These data will contribute to the development of an integrated pest management program for P. abietina based on microbial biological control.

A New Strain of Lecanicillium uredinophilum Isolated from Tibetan Plateau and Its Insecticidal Activity

“…muscarium works with A. nigripes to enhance virulence against Potato Aphid [51], and strains of L. muscarium are also used for the control of B. tabaci, T. vaporariorum, A. craccivora, and Pristiphora abietina. Moreover, the activity of L. muscarium to Aphis craccivora is higher than that of M. pingshaense and B. Bassiana [6,52,53]. The V-3 strain of L. lecanii has a high control effect on whitefly (B. tabaci), with a maximum mortality rate of 90.6%.…”

Biocontrol of the western conifer seed bug, Leptoglossus occidentalis Heidemann (Heteroptera: Coreidae) using indigenous entomopathogenic fungi

“…A loopful of spore suspension from glycerol stock culture was inoculated onto Potato Dextrose Agar (PDA) plates and incubated for 3 days at 28 ± 2 °C in the dark. Then, a single colony was transferred to a fresh PDA plate and incubated for 2 weeks until the plates were fully grown (Biryol et al 2021a).…”

“…Filtrates containing conidia were examined under a light microscope, using a hemocytometer, and conidia in the suspensions were quantified by direct counting. The concentration was adjusted to 10 7 conidia/ml for use in the bioassay (Biryol et al 2021a).…”

“…Conidial transmission of As18 isolate among L. occidentalis was performed on overwintering adults under laboratory conditions. The experiment was performed as previously described by Biryol et al (2021a) with a concentration of 1 × 10 7 conidia/ml. Horizontal transmission was studied with fungus-treated and untreated adults at four vector ratios of 0, 25, 50, 75, and 100% in groups of 40 insects with three replicates.…”

Growth Enhancement and Resistance of Banana Plants to Fusarium Wilt Disease as Affected by Silicate Compounds and Application Frequency

“…Most plant diseases are aided by rains, high air humidity and soil moisture for the establishment and spread of disease-causing pathogens. However, moisture is a commonly recognized environmental factor that controls the transmission of fungal entomopathogens [ 11 ]. Before inducing the blockage of water uptake by roots, the pathogen of FOC will infect the xylem vessels and vascular bundles of the banana [ 12 , 13 ].…”