Journal of Applied Entomologist

Insect pests, snails and spider mite associated with cultivated field peas, and Liriomyza spp parasitoids

Aneesa Saber Sadek — Fri, 05 Jul 2024 00:00:00 +0000

Field pea (Pisum sativum L.) is one of the most popular foods having a high nutritional value for human consumption. This important vegetable crop is liable to infestations of several insect pests that negatively affect the yield quantitatively and qualitatively. The current investigation was carried out at the experimental farm of Sakha Agricultural Research Station, during 2019/2020 and 2021 seasons. The objectives were to monitor the population dynamics of some insect pests, as well as two-spotted spider mite and snail. Also, the parasitoids attacking Liriomyza spp were recorded and monitored. In the first plantation (sown on October 10^th), Liriomyza spp, Bemisia tabaci, Empoasca spp, as well as Tetranychus urticae and the snail, Monacha cantiana were found in considerable higher population densities; compared to Lampides boeticus, Thrips tabaci or Pieris rapae. In the second plantation (sown on January 15^th), the infestations of field peas by Lampides boeticus and Thrips tabaci were higher than these of the first plantation. Four hymenopterous parasitoids were recorded, as emerging from Liriomyza spp pupae: Opius dissitus Muesebeck (Braconidae), Diglyphus isaea Waker (Eulophidae), D. crassinervis Erdos (Eulophidae) and Pediobius spp (Eulophidae). The total parasitism of the four species, during both seasons of study, ranged between 22.18 and 49.76% Liriomyza spp parasitism by Opius dissitus ranged between 3.60 and 5.31%, Diglyphus isaea between 12.99 and 33.33%, D. crassinervis between 2.04 and 8.85%, while that of Pediobius sp. ranged between 2.77 and 4.56%. The obtained results, from the current study, show that parasitoids of Liriomyza spp may contribute effectively in managing the leafminers attacking field peas. Accordingly, application of insecticides to control the dominant insects should be seriously minimized, particularly that P. sativum is mostly consumed as fresh vegetable, as well as the infestations by monitored pests were low in both seasons of study.

Growth of Spodoptera frugiperda on four host plants and its sensitivity to some insecticides using various exposure methods

Abdel Salam A. Farag, Heba S. Abd El-Aty — Fri, 12 Jul 2024 00:00:00 +0000

In the maize fields, fall armyworm, Spodoptera frugiperda (FAW) Smith (Lepidoptera: Noctuidae) is a polyphagous lepidopteran pest, destroying maize crop, causes serious economic damage to corn plants worldwide in recent years especially Egypt. Three different insecticides were application with four exposure methods and four host plants in this research under laboratory conditions against S. frugiperda. Emamectin benzoate was the high efficacy insecticide (LC₅₀ 1.90 mg _{a. i.} / L and Toxicity index 100 %). Therefore, emamectin benzoate was observed the average highest larvae mortality in the larva-dip, leaf-dip, film and spray methods of 83.57, 81.87, 81.25 and 77.27 %, respectively. While, the other insecticides were least toxic with average mortality percentage 75.62 and 48.75 % with, indoxacarb and pyradelil, respectively when the film method was used. The moderate activity of indoxacab and pyradelil spray and leaf-dip methods comparing to that larva-dip method. Also, limited research has been conducted on biological aspects of FAW reared on different plants. Our findings demonstrated that there were various in larvae development period reared on maize had the shortest development duration 16.75 days and pupa period 9.25 days, the fecundity (1650.50 egg) and fertility (95.23 %) were highest, while the larvae (20.00 days) and pupa (14.25 days) duration were the longer fed on cotton, the fecundity (1110.25 egg) and Fertility (66.87%) were least. There were also moderate in the development survival, fecundity and Fertility to FAW reared on cowpea and potato plants. The preferred host of FAW in vitro was maize and other host plants were intermediate host.

Application method of local plant material for effective management of Nematode (Nematoda) infestation in tomato (Lycopersicum esculentus) production

Fri, 02 Aug 2024 00:00:00 +0000

Tomato (Lycopersicum esculentus) is an important global vegetable crop that contributes to nutrient security. Production of this crop is constrained by many factors of which nematode infestation is observed to be quite threatening. The study aimed to determine appropriate method of application of identified local plant materials for effective management of nematode infestation. This was achieved by conducting field trials at Lower Nursery, Njala campus through establishment of experimental plots of tomato host plant in a factorially Randomized Complete Block Design (RCBD) with three replicates in each treatment, repeated twice in the year. The plot size was 18.8 m ×12m with 12 experimental units. The size of each treatment unit was 3m x 4m with 0.6m path between plots and 1 m between replicates. Each plot consisted of 4 rows with 6 plants stands per row. The experimental design consisted of one level of tomato variety (Mongal) and one local plant material which is Siam weed (Chromolaena odorata). Three methods (Pocketing, Ring, and Broadcasting) of identified local plant material were used to determine the appropriate method of application. Data were collected on percentage survival rate, morphological parameters, phenology and yield parameters of tomato host plant respectively. The Data collected were analyzed using Statistical Analysis System (SAS). Differences between mean values of the various parameters were determined by one-way ANOVA analysis while significantly different means were separated using the Student-Newman-Keuls (SNK) test at p≤0.05 level of significance. The Ring method of Chromolaena odorata application yielded the most favorable results. These values were the highest among all methods, indicating superior growth and effective management of nematodes.

Spatial diversity of Lepidoptera and Odonata species of Village Verna

Dafilgo Fernandes, Neville Socorro Cruz Gama, Fulganco Cardozo — Mon, 05 Aug 2024 00:00:00 +0000

Goa is an extension of the Western Ghat biodiversity hotspot, a tropical, bio-diverse region in India. However, basic literature on insect species in Goa on their abundance, distribution and ecology is still lacking. Documenting biodiversity in Goa is important to provide valuable biological information in order to set up the biodiversity conservation and protection strategies to combat rapid regional habitat loss and climate change. This study provides information on the biodiversity of Lepidoptera and Odonata species in one of the small village areas of Verna in South Goa. Verna, with its undulating terrain, is rich in bio-resources but is facing habitat loss due to land use changes in recent years. A total of 181 Lepidoptera species, including 142 butterfly species from 5 families and 39 species of moth from 11 families, as well as 33 species of Odonata, including 20 species of dragonflies from 3 families and 13 species of damselflies from 4 families, were observed in this village. The study also includes the first finding of Protosticta gravelyi in this village. This study data of Lepidoptera and Odonata species collected through photo documentation contribute to the insect population for biodiversity monitoring in Goa.