Endophytic Isaria javanica pf185 Persists after Spraying and Controls Myzus persicae (Hemiptera: Aphididae) and Colletotrichum acutatum (Glomerellales: Glomerellaceae) in Pepper

Abstract

This study endeavored to sustainably control aphids and anthracnose after spraying endophytic Isaria javanica pf185 under field conditions. Under two different tents; one batch of seedlings was sprayed with a 107 conidia/mL I. javanica pf185 suspension; while another was sprayed with 0.05% Tween 80® in distilled water. Six leaf discs from the top; middle; and bottom part of the plant canopy were weekly collected and placed on moistened filter paper in a Petri dish for insecticidal and antifungal bioassays against Myzus persicae and Colletotrichum acutatum. Differences were noticed from the 18th day after spraying with mortality (86.67 ± 0.57% versus 36.67 ± 0.64%) and leaf damage (13.45 ± 0.03% versus 41.18 ± 0.06%) on fungus-treated and controlled, respectively. The corrected insecticidal efficacy was 20.43, 39.82, 72.32, 66.43 and 70.04%, while the corrected fungicidal efficacy was 26.07, 38.01, 53.35, 29.08 and 41.81% during five successive weeks. A positive correlation was evident between insecticidal efficacy and relative humidity (r2 = 0.620) and temperature (r2 = 0.424), respectively. No correlation was found between antifungal activity and relative humidity (r2 = 0.061) and temperature (r2 = 0), respectively. The entomopathogenic fungus survived on leaf surface area and in tissues after spraying.

Pecan plantation age influences the structures, ecological networks, and functions of soil microbial communities

“…Furthermore, the TN content showed a remarkable positive correlation with the relative abundance of Chaetothyriales (Figure 6b). Members of these orders have mostly been characterized as pathogens (Bocco et al, 2021; Nai et al, 2013; Rossman, 1996; Teixeira et al, 2017), which indicates that the increase in soil nutrition with stand age also provides beneficial resources for many pathogens, suggesting that soil health may be threatened when pecans reach a certain age. Hence, plantation management measures such as fertilization and disease control require attention.…”

Inoculation and colonization of the entomopathogenic fungi, Isaria javanica and Purpureocillium lilacinum, in tomato plants, and their effect on seedling growth, mortality and adult emergence of Bemisia tabaci (Gennadius)

“…Seed treatment by Isaria spp. has been successfully shown to be effective for endophytic colonization of pepper [25], eggplant [26], sorghum [27], and English oak [13]. Likewise, inoculation of P. lilacinum via seed treatment has been shown to colonize cotton [12,28].…”