BAKTERI ENTOMOPATOGEN SEBAGAI AGEN BIOKONTROL TERHADAP LARVA Spodoptera litura (F.)

Abstract

Spodoptera litura (F.) (Lepidoptera: Noctuidae) is one of the agricultural pests that attacking almost all kinds of herbaceous plants, especiallyvegetables. Insect control using entomopathogenic bacteria is an alternative strategy that is effective and has a lower environmental impact than the use of synthetic insecticides. The purpose of this research was to explore entomopathogenic bacteria that have insecticidal activity against S. litura larvae at various stages of instars. The result showed that 25% of total number of isolated bacteria have potency as entomopathogenic bacteria. Isolate Staphylococcus sciuri strain BLSP-3 and isolate Serratia sp. strain BLSP-4 showed the highest larvicidal activity against the first and second instar larvae of S. litura 83% and 86%, respectively. The activity against on the third instar larvae however was only by 40%. However, the mortality caused by both isolates was lower than that of Bacillus thuringiensis (more than 90% mortality to the first and second instars and 80 % of the third instar larvae). It is suggested that both of isolates are potential to be developed further as a biocontrol agent to control S. litura population.

Field trial of new Bt-base bioinsecticide formula, Bashield®, for controlling Spodoptera frugiperda J.E. Smith on maize

“…1). The symptoms same with previous study that S. frugiperda which died after two days had a blackish body color, then a few days later the body of S. frugiperda became smaller, dried out, and became destroyed [25], [26]. The death of S. frugiperda is thought to be due to the presence of protein crystals produced by B. thuringiensis which are toxins for lepidopteran.…”

Effectiveness of Bacillus thuringiensis (Bt) application in controlling mortality of Spodoptera litura on rice plants (Oryza sativa L.)

“…This is indicated by LC50 values of 97.74 g and 70.32 g, respectively, while LC90, 147.60 g and 122.21 g, respectively, are suspected of causing test insects' death (Table 1). According to Zulfiana et al and Devi et al [6,24], B. thuringiensis given to S. litura larvae can cause mortality and increase mortality by 100% at 10 HSA doses of 30 g.mL -1. The mechanism of action of B. thuringiensis when entering the body of pests is to produce proteins that will interfere with/neutralize the digestive system of insects so that they cannot process food in the stomach.…”

“…So, the increase in pests will be linear with the development of natural enemies of the organism. The lack of larval mortality at the concentrations is likely due to the bacteria used, whose pathogenicity has been reduced [6], thus affecting mortality from test insects [8,9].…”

“…Insect pests that attack rice plants are identified based on family abundance [5]. In addition, the insect S. litura Fabricius (Lepidoptera: Noctuidae) [6], or armyworm, is an important pest in rice plants [7]. This armyworm attacks rice at night and hides at the base of the plant, in the soil, and hidden places during the day.…”

Eksplorasi Potensi Bakteri Entomopatogen di Areal Tanaman Perkebunan Provinsi Kalimantan Utara

“…Jasad renik dapat dimanfaatkan sebagai agen hayati, misalnya bakteri entomopatogen. Pemanfaatan jasad renik (mikroba) sebagai agen pengendali hayati mengalami kendala, yakni masih terbatasnya strain/jenis bakteri entomopatogen, strain bakteri yang diaplikasi ke daerah yang bukan asal eksplorasi sering mengalami kegagalan karena tidak adaptif (Zulfiana et al, 2017). Menurut Salaki & Tarore (2018), pemanfaatan mikroba lokasi sebagai agen hayati memiliki kelebihan berupa lebih adaptif di lingkungan dibandingkan dengan mikroba dari daerah lainnya.…”