Background: Common bean (Phaseolus vulgaris L.) is a source of antioxidant-containing vegetable protein that is beneficial to human health. The intense cultivation of common bean may result in environmental degradation. Thus, environmentally friendly cultivation methods that use an endophyte to improve productivity are needed. An entomopathogenic fungus, Beauveria bassiana, can serve as an endophyte that stimulates the growth of Gossypium. Therefore, we isolated and identified B. bassiana and also examined its function as a beneficial endophyte that promotes the growth of common bean. Results: An entomopathogenic fungus, B. bassiana, was collected and identified based on macroscopic and microscopic characteristics that were observed during morphological examination. B. bassiana was propagated and inoculated into common bean via seed soaking, soil wetting, and leaf spraying. The soil-wetting and leaf-spraying methods used to inoculate B. bassiana effectively enhanced the growth of common bean, which was observed at day 10 postinoculation. However, no significant growth enhancement of common bean was observed when the seed-soaking inoculation method was used. Conclusions: These results suggest a positive correlation between the B. bassiana inoculation method and growth enhancement of common bean. This study showed the endophytic potency of the fungus that may be used in the development of environmentally friendly cultivation methods of common bean.

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Abundance of rhizospheric bacteria on the IPM-Biointensive system and their antagonistic activities toward Sclerotium rolfsii on soybean.  Abundance of beneficial microorganisms in the soil is one of the active soil indicators the success of integrated pests management (IPM) system.  Some beneficial groups of microorganisms can be used as biocontrol agents.  This experiment was conducted to evaluate the effects of IPM-Biointensive by integrated application of resistant varieties, rice-straw mulch, and biocontrol agents on the abundance of rizospheric bacteria of soybean, also to evaluate the suppressiveness of the bacteria to the mycelial growth of S. rolfsii in vitro.  Abundance of the bacteria was determined by isolation using serial dilution and plate-count techniques.  Suppression to the fungus was evaluated using dual culture technique.  Heat tolerant bacteria had the highest abundance (ranged 1011-1012 cfu/g soil), followed by non-fluorescence bacteria (1011 cfu/g soil), chitinolytic bacteria (106-109 cfu/g soil), and fluorescence bacteria with population range was 103-108 cfu/g soil.  Gepak kuning variety grown with application of rice-straw mulch and PGPR (V2M1P1) caused the highest abundance of rizosphere bacteria.  One of the heat tolerant bacteria, i.e. TP32, caused the highest suppression to the mycelial growth of S. rolfsii in vitro.  Based on the morphology, physiology, and biochemical properties, the isolate was identified as Bacillus sp.

Background The fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), is an invasive alien species in Indonesia. This study aimed to assess the impact of its invasion in Indonesia by measuring the damaged area caused by the pest in maize fields located across East Java and simultaneously determine whether S. frugiperda outcompetes the native Asian armyworm Spodoptera litura (Fabricius). Secondly, the virulence of 14 entomopathogenic fungus (EPF) isolates against S. frugiperda larvae was evaluated in an effort to find effective biocontrol agent candidates. Results The damaged area caused by S. frugiperda was generally higher than that caused by S. litura during the survey period from August 2019 to December 2021. It indicated that S. frugiperda may have dominated the native armyworm and become the primary key pest of maize in Indonesia. Based on a single-concentration assay (106 conidia ml−1), the tested EPF isolates displayed varying degrees of virulence against S. frugiperda larvae, causing larval mortality of 3.5 to 71% at 10-day post-treatment, with the highest mortality rates provided by Beauveria bassiana sensu lato and Trichoderma asperellum sensu lato. At a concentration of 108 conidia ml−1, B. bassiana s.l. and T. asperellum s.l. elicited high larval mortality of 76 and 81%, respectively, at 10-day post-treatment. Nevertheless, the probit analysis based on a concentration–response assay revealed that T. asperellum s.l. had lower LC50 and LC90 values than B. bassiana s.l. Conclusions The attack and invasion of S. frugiperda seem to be a continual threat to the maize agro-ecosystem in Indonesia. As a consequence, Indonesia should mitigate and be well-prepared for future outbreaks of S. frugiperda. Indigenous EPF isolates used in this study may act as promising biocontrol agents of S. frugiperda, especially T. asperellum s.l. This study also serves as the first report documenting the direct lethality of Trichoderma fungus on S. frugiperda larvae.