Tetranychus urticae is an important pest of tomato crops globally, affecting plant yield and growth. Beauveria bassiana and Metarhizium robertsii have the potential to control T. urticae. We investigated the influence of two B. bassiana (i.e., WG-12 and WG-19) isolates and one M. robertsii (WG-02) isolate when colonizing different plant organs (leaves, stems, and roots) and their influence on the growth of tomato plants, through foliar, root-dipping, and seed-soaking application techniques. We also examined the acaricidal activity of the three isolates against T. urticae (female adults), spraying tomato leaf discs with each isolate separately. After 28 days, WG-12 and WG-19 colonized 97 and 91% of the leaves after foliar inoculation, whereas WG-02 exhibited the lowest leaf colonization (76%). The height of the tomato plants, the root length, the number of leaves, and the weight of the biomass above and below the ground were enhanced significantly after inoculation with WG-02 vs. B. bassiana isolates and control. The complete mortality of T. urticae was caused by WG-12 and WG-02 after 10 days, whereas WG-19 killed 94% of the adults. For the effective management of T. urticae, we propose the application of the WG-02 isolate since it provides complete protection and promotes the growth of tomato plants.

Tetranychus urticae (Acari: Tetranychidae) is a widespread and serious mite pest that infests tomato plants and causes economic losses worldwide. We investigated the acaricidal efficacy of two isolates of entomopathogenic fungi (EPF) Metarhizium robertsii (WG-7) and Beauveria bassiana (WG-12) alone and in combination with abamectin when applied topically to tomato leaf discs in the laboratory against T. urticae. We also evaluated the establishment and proliferation of T. urticae mite life stages on tomato plants in the greenhouse after application of each of the above treatments. The combination of abamectin with each EPF caused 100% mortality in T. urticae immatures after 2 days while each EPF or abamectin alone caused moderate mortality, not exceeding 74.2% 3 days post-exposure. Complete (100%) mortality of adults was observed after 5 days in leaf discs treated with M. robertsii plus abamectin whereas B. bassiana plus abamectin caused 100% mortality after 7 days. The mean number of eggs, emerged immatures, and adults were significantly reduced on both sides of the leaves (i.e., abaxial and adaxial sides) after using the combined application of M. robertsii or B. bassiana plus abamectin, compared to abamectin alone and controls. Our results reveal that the acaricidal efficacy of abamectin combined with either EPF was significantly better in managing the T. urticae life stages than either treatment alone under greenhouse conditions.

Rhizoctonia solani is one of the destructive pathogens of the potato crop responsible for stem canker characteristics, root rot, and black sclerotia on tubers, which reduced the market quality of potato. Several management strategies have been adopted to overcome losses inflicted by this pathogen, such as chemical control, organic amendments, cultural practices and the development of resistant varieties. However, none of these management strategies work well to overcome this pathogen. Chemicals are causing severe environmental and health issues. Organic amendments and cultural practices are eco-friendly, however; the pathogen produces resistant sclerotia and can survive for a long time. The development of resistant varieties is laborious and the novel strains of the pathogen rapidly break the resistance of varieties. The present work was carried to evaluate compost extracts as an alternative to chemicals against R. solani. Two commercial composts, sugarcane waste compost and poultry waste were used at three concentrations 30%, 40%, and 50% respectively under laboratory conditions through food poisoning technique. Results revealed that poultry waste compost extract with 50% concentration was found best to manage R. solani as compared with other treatments. Based on our findings it is concluded that compost extract can be augmented for the sustainable management of R. solani for organic production of potato.

Charcoal rot (Macrophomina phaseolina (Tassi) Goid.) can cause significant yield losses in sunflower (Helianthus annuus L.) throughout the world. Fungicide treatments are often used to manage this pathogen, but due to costs and environmental impacts, alternative methods need to be explored. Priming is an adaptive strategy which enables plant defense systems to react more effectively to pathogen attack. The priming phase in plants can be achieved by stimuli from chemicals, beneficial microbes, arthropods, and abiotic stress which can induce defense systems in plants. The present study was conducted to evaluate the effect of different priming agents such as salicylic acid (SA), abscisic acid (AA), gibberellic acid (GA), and jasmonic acid (JA), as either seed or foliar treatments, on charcoal rot on the sunflower. The experiments were conducted under field conditions in two consecutive years (2017-2018). Ten seed of one susceptible (17577) and two moderately resistant (HA-259 and B-224) sunflower cultivars were treated with 2, 4 and 6 mM concentrations of the individual priming agents.. The plants were artificially inoculated with M. phaseolina before sowing by infesting soil, and sixty days after sowing. A number of yield parameters were quantified [head diameter (cm), 100-seed weight (g), achene per head (number), plant height (cm), stem girth (cm), shoot weight (g), root wet and dry weight (g) and chlorophyll content (mg/g)]. Among the priming agents evaluated, AA exhibited a significant impact on all yield parameters at a higher concentration (6 mM) in both susceptible and moderately resistant cultivars, followed by SA, GA, and JA. The results also revealed that seed treatment priming was more effective than foliar priming. There were statistical differences in yield parameters between both years of the study. The AA seed priming treatment showed the most promise for managing charcoal rot of sunflower. The outcome of this study will help to explore an environmentally sound and economically feasible approach for the management of charcoal rot to get sustainability in edible oil production.