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Yard-long bean is one of the most popular vegetables, and is extensively grown in Southeast Asian countries including Cambodia. However, yard-long bean production is severely affected by a plethora of insect pests and diseases, and application of chemical pesticides is the main mode of pest control. In order to reduce the over-reliance on chemical insecticides, we evaluated the effectiveness of microbial pesticides (Bacillus thuringiensis and Metarhizium anisopliae formulations), and neem leaf extract alone and in combination (as an IPM package) against aphids, thrips and pod borer on yard-long bean in three different provinces of Cambodia from 2015 to early 2018. The bio-pesticides reduced the incidences of thrips (Megalurothrips usitatus), and the infestation by the aphid (Aphis craccivora) and the pod-borer (Maruca vitrata) to the levels equivalent to chemical pesticide (abamectin) during trials in 2015 and 2016. Although the yield was significantly higher in bio-pesticide treated plots than untreated plots in 2015, the yield did not differ significantly among the treatments in 2016 trials. Multi-location trials during 2016–2018 confirmed that the performance of the IPM package was on par with Farmers’ practice (calendar-based application of chemical pesticides) in reducing the infestations by target pests, without compromising yield. Hence, the IPM package can be a better alternative to chemical pesticides in managing the key insect pests on yard-long bean in Cambodia.

Resumen El objetivo de la presente investigación fue evaluar el efecto de la tierra de diatomeas (td) y la cal sobre Arion distinctus en condiciones de laboratorio, y sobre ariónidos y agriolimácidos en campo. Se realizaron tratamientos por espolvoreo y aspersión para evaluar su efecto por ingestión y contacto en el laboratorio, y se registró la movilidad y la mortalidad de los ejemplares. En laboratorio se emplearon tres dosis de tierra de diatomeas: 1, 2 y 4 kg/ha, una de cal agrícola a 2 kg/ha, y un testigo; en campo solo se evaluó el método por aspersión con la misma cantidad de variantes, pero en todos los casos se duplicaron las dosis. Se utilizó un diseño de bloque azar en arreglo 5 × 4 y la evaluación se llevó a cabo a través del método de trampas; para ello, se colocaron 20 trampas de refugio por tratamientos. Se determinaron las poblaciones de babosas y la eficacia a los tres y siete días después las aplicaciones. Se aplicó una prueba de comparación de medias de Tukey para las poblaciones en las parcelas tratadas y el testigo. Se obtuvo mayor efecto por contacto que de ingestión. Tanto en las aplicaciones en campo como en laboratorio, las mayores mortalidades se observaron a los siete días, sin diferencias significativas entre la td y la cal. Los resultados obtenidos muestran que la td es útil en el control de estas especies de moluscos y su resultado es mejor con dos aplicaciones. Abstract The aim of this research is to evaluate the effect of d iatomaceous earth (de) and lime on Arion distinctus under laboratory conditions and on arionids and agriolimacids in the field. Dusting and spraying treatments were carried out to evaluate in the laboratory the effect by ingestion and by contact on the mobility and mortality of the specimens. In the laboratory, three doses of diatomaceous earth (1, 2 and 4 kg/ha), one of agricultural lime (2 kg/ha), and one control were used; and in the field, only the spraying method was evaluated with the same number of variants, but in all cases, doses were doubled. A random block design was used in a 5 x 4 arrangement, and the evaluation was carried out through the trap method, and 20 refuge traps per treatments were placed. Slug populations and the efficiency were established three and seven days after the applications. Tukey’s mean comparison test was used for the populations in the treated plots and in the control. A higher effect was obtained by contact compared to ingestion. In both field and laboratory applications, the highest mortalities were observed after seven days, without significant differences between diatomaceous earth and lime. The results obtained show that de is useful in the control of these mollusk species, and better results are obtained with two applications.

This work aimed to study the biology and population parameters of Diaphorina citri in Rangpur and Citrumelo ‘Swingle’ rootstocks and in their combinations with orange scions in Araraquara, Sao Pablo. For the maintenance of a D. citri breeding stock, plants of Murraya exotica L. were used. In each treatment the duration of the biological stages of the pest, viability of the eggs, survival of egg to adult and sexual ratio were evaluated. Egg to adult development time ranged from 15.08 days in Pera / Rangpur to 16.5 days in Hamilim / Citrumelo ‘Swingle’. The highest viability of eggs (82.02 %) of D. citri was observed in the Valencia / Rangpur combination and the lowest in Hamilim / Citrumelo ‘Swingle’ (73.66 %). The egg-adult survival values ranged from 56.16 to 71.07 %, obtaining the lowest survival values in the Hamilim / Citrumelo ‘Swingle’ combination. The lowest mean oviposition (eggs for female) was observed in Citrumelo ‘Swingle’ (185.10). Based on the fertility chart, Rangpur had the highest net reproductive rate (Ro = 160.57) and the shortest generation time (31.54 days). The intrinsic growth rate was higher in the Valencia/Rangpur combination (0.1517). A positive and significant correlation was found between total oviposition and female longevity (R = 0.23440; P = 0.03649) and between the former variable and duration of oviposition period (0.39011, P = 0.0003). Citrumelo ‘Swingle’ and Hamilim / Citrumelo ‘Swingle’ were the treatments that most negatively affected the biological parameters studied mainly oviposition and survival

In this study, the morphological characteristics of each stage of development, duration, survival, ecological parameters, reproductive capacity, longevity of adults, and stage-specific mortality of Diaphorina citri (Hemiptera: Liviidae) were determined. It was conducted in a greenhouse (maximum temperature: 37.1 ± 5.1 °C, minimum temperature: 25.0 ± 2.0 °C; maximum relative humidity: 67.0 ± 6.2%, minimum relative humidity: 39.5 ± 10.9%; 12: 12 h Light: Dark, natural light conditions) in the municipality of Palmira, Valle del Cauca. Mean time from egg to adult was 15.41 ± 0.49 days. The median survival time for females was 48.25 days and 50 days for males. The survival rate to adult stage of D. citri was 6.86% with the highest mortality rate recorded for first-instar nymphs (81%). Females oviposited an average of 237 eggs during their reproductive cycle. A dichotomous key, an essential tool for conducting biological studies, is provided to separate the different growth stages of the Asian citrus psillid. Studies on the biology of D. citri will serve as a baseline for the mass rearing of its parasitoid, T. radiata.

Yard-long bean is one of the most popular vegetables, and is extensively grown in Southeast Asian countries including Cambodia. However, yard-long bean production is severely affected by a plethora of insect pests and diseases, and application of chemical pesticides is the main mode of pest control. In order to reduce the over-reliance on chemical insecticides, we evaluated the effectiveness of microbial pesticides (Bacillus thuringiensis and Metarhizium anisopliae formulations), and neem leaf extract alone and in combination (as an IPM package) against aphids, thrips and pod borer on yard-long bean in three different provinces of Cambodia from 2015 to early 2018. The bio-pesticides reduced the incidences of thrips (Megalurothrips usitatus), and the infestation by the aphid (Aphis craccivora) and the pod-borer (Maruca vitrata) to the levels equivalent to chemical pesticide (abamectin) during trials in 2015 and 2016. Although the yield was significantly higher in bio-pesticide treated plots than untreated plots in 2015, the yield did not differ significantly among the treatments in 2016 trials. Multi-location trials during 2016–2018 confirmed that the performance of the IPM package was on par with Farmers’ practice (calendar-based application of chemical pesticides) in reducing the infestations by target pests, without compromising yield. Hence, the IPM package can be a better alternative to chemical pesticides in managing the key insect pests on yard-long bean in Cambodia.