Andalasian International Journal of Entomology

Insects Induced Mango Fruit Rot: Unraveling the Culprits

Sivagami Subramaniam — 2024-04-18

Plant diseases and pests are important factors determining plant yield production, including mango. Mango is an economically important fruit crop in tropical and subtropical areas. Mango fruit rot caused by insects and microbes has become a significant threat to mango production in Southeast Asia and worldwide. Insect plant pathogens affect crop yields' profitability, quality, and quantity. Some infections could occur before harvest and remain dormant until the favourable condition is achieved, and the disease will break out after harvest, reducing mango production. They act as a threat to the crops through various mechanisms of pathogenesis that compromise the immune system of the plants, such as developing any ways to attack the plants, seeking entry via open pores or exposed surface or wound, and sourcing nutrients forcefully for their growth and development. Depending on the environmental factors, the insect contracts the host through primary or secondary infection. This paper summarizes mango fruit rot disease caused by insects groups such as fruit borers (Autocharis albizonalis and Citripestis eutraphera), fruit flies (Bactrocera dorsalis), and mango seed weevils (Sternochetus mangiferae). This review will provide information about fruit rot diseases on mangoes caused by insects, the mechanism of infection, the interaction between insect damage and fungal infections, effective control methods, and related integrated pest management approaches.

Color Variability of Cosmopolitan Beetles in Mindanao, Philippines

Ernel Bagbag — 2024-04-10

Beetles (Insecta: Coleoptera) stands out as one of the most diverse insect groups, showcasing various color variations. These evolved color patterns present a fascinating trait crucial for understanding their evolution. However, studying these patterns poses challenges, given the intricate nature of colors in the natural world. While past researchers have explored beetle color patterns, quantifying colors requires costly equipment and sophisticated software. This paper introduces an alternative approach, utilizing digital images to examine color variability among Coleopterans. Forty-eight specimens from Mindanao, Philippines, were collected and photographed under consistent conditions. Subsequently, the images were calibrated and processed in R software to calculate image distances through cluster analysis. The results reveal that beetle color patterns fall into two categories: a dark color with deeper shades of gray and a moderately bright tone featuring a slight reddish hue with noticeable yellow highlights. Chrysochroa fulminans is the most distinct beetle across Coleopteran species due to its vibrant green coloration. Family-specific examination of color patterns revealed species with distinct color, Anomala flavipennis and A. smaragdina (Scarabaeidae), Otiorhynchus pauxillus (Curculionidae), Uloma culinaris (Tenebrionidae), and Nupserha fricator (Cerambycidae). The study's findings offer valuable insights into the evolution of Coleopterans, mainly their color patterns, serving as a valuable tool for classification.

Diversity and Host Ranges of Whiteflies in Mekarsari Fruit Park, Bogor: a Comprehensive Study of 20 Whitefly Species Across 56 Fruit Plant Species

Purnama Hidayat — 2024-04-11

Mekarsari Fruit Park, situated in Bogor, boasts an extensive collection of 226 fruit species. Apart from vegetables and ornamentals, fruit plants play a significant role as hosts for whiteflies. Whitefly infestations can disrupt photosynthesis and respiration, affect the aesthetics of ornamental plants, and transmit plant diseases caused by viruses. The primary objective of this study was to assess the species diversity of whiteflies and their host ranges within Mekarsari Fruit Park. Purposive sampling was employed, followed by preparing collected samples for microscope slides and identification. A total of 20 whitefly species were collected from 56 fruit plant species spanning 20 different families. Of the 20 collected species, 16 were successfully identified, while four remained morphospecies. These whiteflies were categorized into two subfamilies: 17 species belonging to the Aleyrodinae subfamily and three species belonging to the Aleurodicinae subfamily. Paraleyrodes minei emerged as the most prevalent whitefly species, infesting 14 host plants across 11 families. Furthermore, the study revealed that 14 whitefly species were found exclusively on one fruit plant species, one whitefly species on two fruit plant species within the same family, and seven whitefly species on multiple fruit plant families. The Euphorbiaceae and Rubiaceae families were the most susceptible to whitefly infestation among the fruit plants.

Induction of Resistance to Larvae Crocidolomia pavonana F. (Lepidoptera: Crambidae) using Rhizobacteria to the Cabbage

Indri Yanil Vajri — 2024-04-11

Crocidolomia pavonana is a significant pest on cabbage that reduces the quality and quantity of cabbage. Utilizing microorganisms such as rhizobacteria is an alternative environmentally friendly control that can potentially suppress the development of this pest. The study aimed to obtain rhizobacteria isolates capable of colonizing cabbage tissue and inducing plant resistance to C. pavonana larvae. The research was conducted at the Biological Control Laboratory and Greenhouse, Faculty of Agriculture, Universitas Andalas, Padang. The study used a Completely Randomized Design (CRD) with ten treatments and five replications. The treatment consisted of rhizobacteria isolates, including Bacillus thuringiensis, Bacillus subtilis, Serratia marcescens, Stenotrophomonas maltophilia, as well as a negative control (aquadest sterile) and a positive control (Cypermethrin insecticide). The test was carried out by soaking the seeds in a suspension containing rhizobacteria with a population density of 10⁸ cells/ml. The variables observed were larval mortality, pupa and imago formation percentage, and increased salicylic acid production. The data were analyzed using variance and continued with the LSD further test at the 5% level. The results showed that all rhizobacteria isolates colonized into cabbage plant tissue could kill C. pavonana larvae and inhibit these insects' biological development. B. thuringiensis KJKB7.3 showed better results with the highest mortality value (62.67%). Soaking cabbage seeds with rhizobacteria can increase the content of salicylic acid. Based on this research, the rhizobacteria used in the research have the potential to be developed as biological agents to control C. pavonana.

Climate and plant phenology (plant age and growth stage) influence Rhopalosiphum padi L. abundance on wheat plants in Luxor Governorate, Egypt.

Moustafa Mohamed Sabry Bakry — 2024-04-14

Field experiments were conducted at El-Mattana Agricultural Research Station, Luxor Governorate, during two successive wheat growing seasons (2017/18 and 2018/19). This was to study the seasonal abundance of Rhopalosiphum padi (Hemiptera: Aphididae) on wheat plants (Giza 171 cultivar). We also investigated the effects of climate and plant phenology on the R. padi population density. Results indicated that R. padi infested wheat plants from December 17, 2017, until April 8, 2018, within the first growing season (2017/18), and from Jan. 27^th, 2019, up to April 13^th, 2019, within the second growing season (2018/19). The cumulative counts of R. padi in growing season one was 9486.17, and in growing season two, 3444.00 individuals. The mean population of R. padi per 10 tillers over the whole first season was 80.12 ± 7.90, and for the second season, 42.36 ± 2.96. The first season, December, January, and February, had the most favorable climate for R. padi population growth (measured during weekly inspections). In contrast, February and March were more favorable in the second season. R. padi was not detected on the wheat during the wheat maturation period within both growing seasons. The combined effects of climate and plant phenology strongly correlate with R. padi population density, with explained variance (EV) of 93.86% in the first season and 99.11% in the second season. Daily mean maximum temperature was the most influential variable explaining changes in total R. padi population, with EV 28.37%in the first season and 28.62% in the second season. The data provided here can assist in the design of Integrated Pest Management (IPM) programs for aphid control on wheat plants.

Level of Pest Infestation on Cocoa (Theobroma cacao L.) Variety BL-50 in Tanah Datar Regency, West Sumatera Province, Indonesia

Muhammad Al-Ikhlas — 2024-04-15

West Sumatra Province is one of the cocoa production centers in Indonesia. Cocoa farmers in the Lima Puluh Kota District in West Sumatera Province had successfully developed a superior clone of cocoa plants resulting from participatory selection, which was later coded BL-50. The main pests that attack cocoa plants are the urgent problem in cocoa cultivation, resulting in decreased productivity. This study aims to determine the level of significant pest attacks on cocoa varieties BL-50 in Tanah Datar Regency. This research is in the form of a survey with a purposive sampling method. Sampling is carried out systematically diagonally in the field. The highest attack rate of Cocoa Fruit Borer in Tanah Datar Regency is in Rambatan District, with the percentage of affected plants, the percentage of infested fruits, and the highest attack intensity, respectively 51,.25%; 31.58% and 21.10%, the lowest were in Lintau Buo Utara District with 30.93%; 20.70% and 13.96%. The highest attack rate of cocoa fruit-sucking ladybugs in the BL-50 variety is in Rambatan District, 66.09%, 45.07%, and 30.45%. At the same time, the lowest is in the Lintau Buo Utara District, with a percentage value of 41.56%, 27.66%, and 18.30%. Excellent and regular land sanitation activities have played a role in minimizing the level of pest attacks in Lintau Buo Utara.