The susceptibility of six milled rice varieties Ciherang, Membramo, Cibogo, Sembada, to the Lesser Grain Borer (Rhyzopertha dominica, F) was studied by No Choice Test Method under laboratory condition (27 ± 2℃and 65 ± 5% RH). The Susceptibility was assessed on the basis of eggs number laid by female insects, the number of F 1 progeny emerged, the weight loss of infested samples and also the Dobie's Index of susceptibility. The results revealed that the number of eggs laid by female insects, the number of F 1 progeny emerged and weight loss of infested samples were significantly low in Membramo variety followed by Ciherang, IR-64, Cibogo, Sembada and Intani-2. Based on the index of susceptibility, the milled rice variety of Membramo had the lowest susceptibility index and was regarded as resistant. While the milled rice varieties of Ciherang, IR-64, Cibogo and Sembada were considered as moderately resistant, Intani-2 seen as the most highly susceptible. These results imply that the milled rice variety with high phenolic content and hardness potentialy revealed resistant to the R. dominica infestation.

The Research was aimed to identify the diversity of arthropods in Cocoa plantation in three strata of shade tree. Research was conducted in Rahmat village, the sub-district of Palolo, District of Sigi, the Province of Central Sulawesi, Indonesia from December 2012 to June 2013.Berlese funnel, Pitfall, Malaise and Light trap were used to collect arthropod samples. There were five indices such as species richness (R), species evenness (E), species diversity (H`and D), and species similarity (Iss) to analyze the diversity of arthropods in cocoa plantations. The result showed that species richness (R) of arthropods under the two strata of shade tree, species evenness (E) and both of species diversity indices, Shannon (H`) and Simpson (D) was the highest, with value of 18.216, 0.839, 4.383, and 0.833 respectively. In addition, percentage of species similarity (Iss) was the highest under two strata of shade tree with value 72.297%.

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Abstract. Thei RSP, Abadi AL, Mudjiono G, Suprayogo D. 2020. The dynamics of Arthropod diversity and abundance in rice field ecosystem in Central Lombok, Indonesia. Biodiversitas 21: 5850-5857. Arthropods have roles as pests, decomposers, pollinators, and natural enemies of pests. Natural enemies play a vital role in pest population control by predation or parasitism. A study of the arthropod community in the rice field ecosystem was conducted in Central Lombok, Indonesia from December 2009 to March 2010 in order to elucidate the composition, structure, and dynamic diversity of arthropods present. Arthropod sampling was done by pitfall traps, yellow pan traps, and insect net. Arthropod dynamic diversity, especially of natural enemies, was determined by diversity index, dominance index, evenness analysis, and pictorial analysis. Based on taxonomical perspective, as many as 98 arthropod species were found, including 85 insect species from 59 families and 9 orders; and 13 spider species in 6 families. Based on the ecological functions, predator arthropods were the most common (33 species, dominated by spiders), but the phytophage arthropods had the most species richness (49.34%). A high Shannon index (3.18) and Pilou index (0.7) indicated dominant arthropods in the ecosystem. Arthropod species richness and diversity increased alongside rice development and decreased after harvest.

Asian citrus psyllid (ACP) Diaphorina citri Kuwayama is a serious problem in citrus because it transmits huanglongbing (HLB) disease. Agricultural practices without paying attention to the agroecosystem complexity often cause the agroecosystem more suitable for insect pests proliferation and less friendly to natural enemies. The research aims to study the effectiveness of agroecosystem management compared to conventional farming in the ACP control. The effects of both treatments on the diversity and abundance of ACP’s natural enemies as well as the incidence and severity of HLB were also studied. Agroecosystem management consists of preventive and responsive actions. Preventive action was carried out through a polyculture system, planting refugia and legume cover crop, providing beetle banks, applying lime, applying organic and inorganic fertilizers, citrus pruning intensively, maintaining drainage ditches, and mechanical weed control. Responsive action is short-term control when the abundance of ACP reaches the action threshold. Responsive action was carried out through biological or chemical control. Meanwhile, conventional farming is a series of conventional farming and pest control techniques commonly applied by farmers. Each treatment was applied in three orchards of Siam Orange cv. Pontianak Citrus nobilis Lour var. microcarpa Hassk. The results showed that agroecosystem management was more effective in controlling the ACP population so that its abundance was lower and less fluctuated than conventional farming. ACP’s natural enemies in agroecosystem management were also more diverse than conventional farming. The abundance of ACP’s natural enemies and the incidence and severity of HLB in the two treatments were not significantly different.

Abstract. Prabowo H, Rahardjo BT, Mudjiono G, Rizali A. 2021. Impact of habitat manipulation on the diversity and abundance of beneficial and pest arthropods in sugarcane ratoon. Biodiversitas 22: 4002-4010. Sugar production in Indonesia faces several challenges such as infestation of pests and diseases that lead to decline in sugarcane production and productivity. In order to overcome the loss of yields from the presence of pests, alternative new approaches are sought by solving of the problem that can have a sustainable impact by applying habitat manipulation. Habitat manipulation changes the diversity and density of arthropods populations in agro-ecosystem. In the concept of managing agroecosystems with habitat manipulation, it is hoped that the development of agro-ecosystem resilience against pest management will be expected to be suistainable. The results showed that there was an increase in the number of arthropods in the research area for 20 weeks after the management of agro-ecosystems through habitat manipulation. The arthropods in all the traps were dominated by Collembola, Diptera, Coleoptera, Aranea, and Hymenoptera. There were 44 genera that belong to predators and 8 species are belonging to parasitoids. The diversity index of Shannon-Wiener (H '), Simpson Dominance (C) and Species Evenness (E) was not significantly different between treatment and control, but habitat manipulation treatment was able to increase the number of detritivores, predators, parasitoids, and pollinators by 38.81; 43.88; 58.4; and 75.35%. The full role of arthropods in the food chain of the sugarcane ecosystem has been identified and efforts are needed to optimize the role of natural enemies in the agroecosystem to maintain ecosystem stability. Habitat manipulation can increase the number of beneficial insect populations in short run, but it might take time to increase their diversity in agroecosystem.

As an important pest, Helopeltis Antonii reduces cocoa yields ca. 32-44 %. Related to H. antonii, this research aimed to identify the arthropods diversity, population and attack intensity of H. antonii in three different managements of cocoa plantations i.e. Kedaton, Banjarsari and Nogosari, Jember district, East Java, Indonesia from February 2014 to February 2015. The arthropod collection was done by visually, sweep net, yellow pan, malaise and pitfall traps. Arthropods diversity and similarity were analyzed by Margalef species richness index (R), Shannon-Wiener diversity index (H'), Evenness index (E), Simpson dominance index (C) and Sorensen Similarity index (SS). The different number of arthropod, population and attack intensity of H. antonii between plantations were examined by Wilcoxon test. The research showed that the highest species richness, diversity and evenness index values was in Nogosari and it was in a stable condition. About 10 orders, 35 families and 41 species of arthropods in Nogosari, it was higher than two other cocoa plantations. Nogosari was different from Kedaton and Banjarsari based on Sorensen Similarity Index with 78.26 and 77.78 % respectively. In addition, population dynamic and attack intensity of H. antonii in the three cocoa plantations were different in a year.

Rhyzopertha dominica reduces the weight of rice production at approximately 40 %. This study aimed to investigate the physical and biochemical characteristics of resistance in different rice varieties at different initial moisture content to their susceptibility against R. dominica. The study consisted of 2 experiments: (i) free-choice, and (ii) no-choice tests. These experiments were conducted by combining 6 rice varieties (Vi): IR-64, Ciherang, Membramo, Cibogo, Sembada, and, Intani-2, and 4 levels of initial moisture content (Ki): 10, 12, 14, and 16 %. The observed variables for the free-choice test were the number of adult insects (male and female) present, the number of females present, and the percentage of weight loss. The observed variables for the no-choice test were the number of eggs, larvae, F1 progeny emerged, and the median developmental time of R. dominica. Results of the free-choice test revealed that the highest total number of adult insects present, the female insects present, and the percentage of weight loss appeared in the Intani-2 variety at 16 % initial moisture content, while the lowest of these 3 variables appeared in the Membramo variety at 10 % initial moisture content. The no-choice test revealed that the rice varieties became more susceptible with the increase of the initial moisture content. The susceptibility of rice was affected by hardness, ash content, and phenol content. Rice hardness level were caused by the level of initial moisture content. However, the chemical characteristics of the rice were not affected by the level of initial moisture content.