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Background Under laboratory and greenhouse conditions, the virulence of 2 isolates of Thai indigenous entomopathogenic nematodes (EPNs) in controlling the fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith) (Lepidoptera; Noctuidae), was demonstrated. Six EPNs dosages were tested against 2 larval instars of FAW under the laboratory conditions, while 2 different concentrations were tested under the greenhouse conditions. Results The results of a laboratory experiment revealed that 2 Thai indigenous EPNs isolates (Heterorhabditis indica isolate AUT 13.2 and Steinernema siamkayai isolate APL 12.3) were efficient against the FAW, 2nd and 5th larval instars. Six different nematode concentrations (50,100, 150, 200, 250 and 300 infectious juveniles (IJs) ml−1) were evaluated, and all were proven to be effective, with the mortality rate associated with concentration. Inoculated larvae in the 2nd instar was more vulnerable than that in the 5th instar. H. indica isolate AUT 13.2 was more destructive than S. siamkayai isolate APL 12.3. The greatest mortality rate of 2nd instar larvae was 83% when H. indica AUT 13.2 was applied at the concentration of 250 IJs ml−1, and 68% when the nematode S. siamkayai APL 12.3 was used at the concentration of 300 IJs ml−1. At 250 IJsml−1, the highest mortality rate of the 5th instar larvae was 45% for H. indica AUT 13.2 and 33% for S. siamkayai APL 12.3, respectively. To customize the concentration and volume of nematodes suspension evaluated in the greenhouse settings, the most sensitive stage of FAW and the optimum concentration that caused the highest mortality were used. The concentrations of both indigenous nematodes’ isolates were 20,000 and 50,000 IJsml−1 per pot, respectively, and the results showed that the mortality rates were lower than that in the laboratory. FAW mortality rate was the highest (58%) in case of the nematode H. indica isolate AUT 13.2, against (45%) in case of S. siamkayai isolate APL 12.3, at the 50,000 IJs ml−1 concentrations. Conclusions The study revealed the 2 Thai indigenous EPNs isolates (H. indica isolate AUT 13.2 and S. siamkayai isolate APL 12.3) were capable of controlling the FAW in both laboratory and greenhouse environments. The 2 Thai EPNs showed the potential to be considered as a biological control agent.

The environmental and health impacts on the case study 'Khok Saat community' of the toxic substances and gases produced in this e-waste processing, are obvious and measurable. Two scenarios were developed. A life cycle assessment approach was carried out focusing on the end-of life phase. The ReCiPe Endpoint (H) v.

A field experiment was conducted to evaluate cropping and management techniques for chilli plants under rain-fed conditions. Cropping included a standard farmers style bed (designated as CL1.1), a specially modified bed (CL1.2) and a standard farmers bed (no flower removal) as the control (CL1.3). Management included 1st bottom three flower removal in CL1.1 (designated as ML1.1) and CL1.2 (ML1.2). The result showed that chilli cultivated in CL1.2 outperformed both CL1.1 and CL1.3 in all tested aspects including growth, yield, soil moisture content and soil properties. CL2.3 performed the lowest in all parameters. ML2.2 exhibited ML1.1 in plant-height, leaf-length, leaf-breadth, fruit-girth, fruit number per plant, OC%, pH and NPK. ML2.1 performed the maximum in stem diameter, leaf number, fruit weight, girth-apex, fruit-length with pedicel and fruit-length. Considering the combination effect of cropping and management levels, CL1.2*ML2.2 outperformed CL1.3*ML0 in all traits. These results indicated the characteristics of the specially modified plot and 1st bottom three flower removal in a modified plot was the recommended combination under rain fed farming.