Conservation Of Natural Enemies Research Articles

Conservation of natural enemies of Diaphorina citri and their impact on Huanglongbing: Analysis and perspectives

Diaphorina citri is the main vector of Candidatus Liberibacter asiaticus (CLas), the causative agent of HLB, the most devastating citrus disease. Although the importance of biological control is recognized, insecticides are the main control tool used. Its use in citrus should be cautious, as it could interfere with the biocontrol of exotic pests already present. Diaphorina citri has a wide range of natural enemies; however, only the parasitoid Tamarixia radiata and some species of entomopathogenic fungi are used inundatively. Although the main predators of the vector occur naturally, few studies address their conservation in situ. This review supports the idea that the conservation of natural enemies should be the basis of the integrated management of D. citri and CLas. The conservation of alternate hosts, the inclusion of nectar plants, in situ conservation of parasitoids, and the autodissemination of entomopathogenic fungi are proposed. Studies carried out on conservation of natural enemies of D. citri and related pests, their probable impact on the disease, and prospects for implementation in Mexico are analyzed and discussed. The proposed strategies could enhance not only the biological control of D. citri-CLas, but also the autoregulation of citrus pests in general.

Entomopathogens and their role in insect pest management

Agricultural production faces significant challenges due to the loss of crop yields, highlighting the need for improvements in pest management methods to enhance productivity. Crop growers are increasingly pressured to minimize the use of chemical pesticides without compromising yields. However, managing pests has become more challenging due to pesticide resistance and limited product availability. Consequently, there is an urgent requirement for alternative approaches. Entomopathogens such as fungi, bacteria, viruses, and nematodes emerge as promising alternatives to broad-spectrum chemical insecticides. They have been widely employed to control insect pests in cultivated crops, employing successful strategies such as augmentation and classical biological control. These methods involve applying or introducing bacteria, baculoviruses, fungi, and nematodes. Utilizing entomopathogens offers numerous benefits beyond their effectiveness. These advantages encompass the capacity to treat expansive areas with a sole application, ensuring safety for both humans and non-target organisms. Additionally, their use leads to decreased pesticide residues in food, the conservation of natural enemies, and a boost in biodiversity within managed ecosystems. Entomopathogens present a viable solution by offering effective pest control while addressing environmental, human health, and ecosystem sustainability concerns. The primary emphasis of this review is on the present condition of bio-formulations, the pathogenicity associated with entomopathogens, their mode of action, and the possible implementation of diverse microbial formulations aimed at achieving sustainable pest management.

Effects of thiamethoxam on physiological and molecular responses to potato plant (Solanum tuberosum), green peach aphid (Myzus persicae), and parasitoid (Aphidius gifuensis).

To improve integrated pest management (IPM) performance it is essential to assess pesticide side effects on host plants, insect pests, and natural enemies. The green peach aphid (Myzus persicae Sulzer) is a major insect pest that attacks various crops. Aphidius gifuensis is an essential natural enemy of M. persicae that has been applied effectively in controlling M. persicae. Thiamethoxam is a neonicotinoid pesticide widely used against insect pests. The current study showed the effect of thiamethoxam against Solanum tuberosum, M. persicae, and A. gefiuensis and the physiological and molecular response of the plants, aphids, and parasitoids after thiamethoxam application. Thiamethoxam affected the physical parameters of S. tuberosum and generated a variety of sublethal effects on M. persicae and A. gefiuensis, including nymph development time, adult longevity, and fertility. Our results showed that different thiamethoxam concentrations [0.1, 0.5, and 0.9 μm active ingredient (a.i.)/L] on different time durations (2, 6, and 10 days) increased the antioxidant enzyme activities SOD, POD, and CAT of S. tuberosum, M. persicae, and A. gefiuensis significantly compared with the control. Our results also showed that different thiamethoxam concentrations (0.1, 0.5, and 0.9 μm a.i./L) on different time durations (2, 6, and 10 days) increased the expression of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), acetylcholinesterase (AChE), carboxylesterase (CarE) and glutathione-S-transferase (GST) genes of S. tuberosum, M. persicae, and A. gefiuensis compared with the control. Our findings reveal that using thiamethoxam at suitable concentrations and time durations for host plants and natural enemies may enhance natural control through the conservation of natural enemies by overcoming any fitness disadvantages. © 2024 Society of Chemical Industry.

Keanekaragaman dan komposisi spesies laba-laba predator dan parasitoid Hymenoptera pada tanaman jagung dengan dan tanpa refugia pada musim yang berbeda

Refugia are plants that play an important role in the conservation of natural enemies in agroecosystem. Refugia plants are useful for providing shelter and host/prey for natural enemies, especially parasitoids and predators. This study was aimed to investigate the effect of refugia and different planting seasons on the diversity and species composition of natural enemies (especially predatory spiders and Hymenoptera parasitoids) in maize fields. Field research was conducted in two different seasons i.e., dry season (April to July 2022) and rainy season (September to December 2022) in Tumpang Village, Malang District. The maize fields for the study were grouped into four different areas, with two observation plots (size 40 m × 50 m) in each area, consisting of a monoculture maize field (control plot) and a maize field with refugia plants (treatment plot). Sampling was conducted using pitfall traps (for predatory spiders) and yellow traps (for Hymenoptera parasitoids). Traps were set for 1 × 24 hours and conducted at 2, 4, 6, 8, 10 and 12 weeks after planting (WAP). The results from two planting seasons were obtained predatory spider diversity amounted to 626 individuals consisting of 7 families, and 40 morphospecies, while Hymenoptera parasitoids amounted to 787 individuals consisting of 5 families, and 63 morphospecies. Based on generalized linear models (GLM) analysis, it was found that refugia planting did not affect the diversity of natural enemies, but affected the species composition of predatory spiders. Different planting seasons affect the diversity and species composition of predatory spiders as well as Hymenoptera parasitoids.

Flowering margins support natural enemies between cropping seasons

IntroductionPopulations of natural enemies of insect pests are declining owing to agricultural intensification and indiscriminate use of pesticides, and this may be exacerbated in agricultural systems that clear all margin plants after the cropping season for other uses such as fodder. Retaining a diversity of non-crop flowering vegetation outside the cropping season may support more resilient and effective natural pest regulation.MethodsWe tested the potential for non-crop vegetation to support natural enemies in fields across two locations after harvesting the primary crops of lablab and maize.ResultsA total of 54 plant species were recorded across the sites in Kenya with 59% of them being annuals and 41% perennials. There was a significant seasonal variation in plant species richness (ANOVA: F1, 16 = 33. 45; P< 0.0001) and diversity (ANOVA: F1, 16 = 7.20; P = 0.0511). While time since harvesting was a significant factor influencing the overall abundance of natural enemies (ANOVA: F2, 1,133 = 8.11; P< 0.0001), they were generally higher in abundance in locations with margin plants or where a diversity of margin plants was observed.DiscussionThese findings demonstrate that flowering plants in agricultural systems offer refuge and alternative food for natural enemies and potentially other beneficial insects between cropping seasons. The conservation of natural enemies between crops may lead to more effective natural pest regulation early in the following crop, thus reducing reliance on insecticides application.

Constraints in Adopting Biological Based Pest Management Strategies

Biological control of insect pests is a “viable alternative” to insecticides with an aim to suppress the pest populations below economic injury levels and is the need of the hour. The key biological based management strategies include erection of pheromone traps for mass trapping/monitoring the incidence of moths (adults) of insect pests; conservation of natural enemies like predators/parasitoids in crop ecosystem; augmentation and inundative release of bio-agents like parasitoids and predators against the targeted pests; and application of bio-rational or “reduced risk” insecticides that effectively controls the insect pests and non toxic to other organisms with meager environment risk. Many research findings had strongly witnessed the biological pest management as superior method in suppressing the pest infestation levels in almost all crops, but the success rate is not substantial at farmer’s level. In order to assess the constraints in adopting biological methods and restraints in low success rate of these methods in suppressing the insect pests an explorative research study was conducted for a period of two successive years i.e., 2020-2021 and 2021-22. A total of ten mandals in Krishna district of Andhra Pradesh was selected for the study wherein biological based management strategies are being practiced by the farmers. From each mandal three villages were randomly selected and from each mandal ten farmers were chosen for personal interview to document the constrains in adopting bio-control methods. The methodologies being practiced by farmers were also recorded. The results inferred that among the various restraints, non availability of bio-control agents/materials at market level (63%), adopting the methods at improper time (59%) and lack of knowledge on pest behavior/ecology (55%) are the major influencing factors for low success rate of biological control at farmer’s level. It can be accomplished from the present study that adoption levels of biological pest management strategies at farmers are to be strengthened by conducting regular training programmes, result demonstrations, front line demonstrations and also by encouraging farmers through some incentives and certifications of the harvested organic produce.

Keanekaragaman Coccinellidae Predator pada Ekosistem Pertanian Organik dan Anorganik di Provinsi Sumatera Barat

The main principle of pest control in organic farming is to reduce the use of synthetic chemicals, especially pesticides. On the other hand, pest control in agricultural systems prioritizes the conservation of natural enemies in these ecosystems. Coccinellidae predators are one of the potential natural enemies available in organic farming ecosystems. To optimize the potential of these natural enemies, it is necessary to study the diversity of these predators in organic farming. By knowing the species and abundance of Coccinellidae predators in organic farming ecosystems, a suitable conservation model can be designed for these natural enemies so that these predators can carry out their functions to control pests, especially aphids. This study aims to study the diversity of predatory Coccinellidae in organic and inorganic agriculture in West Sumatra Province. Coccinellidae predators are collected directly and use insect nets. The diversity of Coccinellidae predators was analyzed with the Shannon Winner and Simpson abundance indexes. Based on the exploration carried out on several organic farms in West Sumatra, 18 species of Coccinellidae Predators have been collected, and six species have not been identified. Next, it is proven that organic farming has a high diversity of 1.90 compared to inorganic farming, which is 1.65. The presence of predatory Coccinellidae in organic farming is more evenly distributed, namely 0.67. Menochilus sexmaculatus is one species that has the potential to be optimized as a biological control agent for aphids.

Survival, Development, and Fecundity of Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) on Various Host Plant Species and Their Implication for Pest Management.

Spodoptera frugiperda is Indonesia's relatively new invasive polyphagous insect pest. So far, S. frugiperda infestation has only been reported in corn and rice in Indonesia. However, S. frugiperda is known to feed on many commercial crops in other countries. To date, information on the biological parameters of S. frugiperda is limited in Indonesian ecologies. Since host plants are a critical factor for insect life history and have the potential to be used for pest control strategies, it is essential to study the biology and survival of S. frugiperda on different host plants. This research aimed to investigate the survival, development time, and fecundity of S. frugiperda on other host plant species to predict possible infestation rates for use in pest management. The study was conducted by rearing S. frugiperda on 14 common cultivated host plant species in Indonesia. The survival rate, development time, fecundity, and potential attack rate of S. frugiperda on various tested host plants were analyzed in this study. The findings revealed that corn was the primary host for S. frugiperda. The ability of S. frugiperda to survive on papaya, water spinach, banana, spinach, cucumber, and coco grass indicates that these plants are potential alternate hosts for S. frugiperda. Long beans, bok choy, choy sum, and beans might be indicated as a shelter for S. frugiperda. Meanwhile, inappropriate hosts for S. frugiperda include cabbage, broccoli, and cauliflower due to their low survival rate on these plants. This research indicates that these plants have the potential to be used as a hedge, trap, or bunker plant in S. frugiperda management strategies. However, to prevent detrimental damage, control methods are needed in an integrated manner, including monitoring pest populations, habitat manipulation, and conservation of natural enemies.

Herbicides Harm Key Orchard Predatory Mites.

The phytoseiid mites Galendromus occidentalis and Amblydromella caudiglans are critical for conservation biological control of pest mites in Washington State, U.S.A. apples. While the non-target effects of insecticides on phytoseiids are well described, research on herbicide effects is limited. Using laboratory bioassays, we examined lethal (female mortality) and sublethal (fecundity, egg hatch, larval survival) effects of seven herbicides and five adjuvants on A. caudiglans and G. occidentalis. The effects of mixing herbicides with recommended adjuvants were also tested to determine if the addition of an adjuvant increased herbicide toxicity. Glufosinate was the least selective herbicide tested, causing 100% mortality in both species. Paraquat caused 100% mortality in A. caudiglans and 56% mortality in G. occidentalis. Sublethal effects were significant for both species when exposed to oxyfluorfen. Adjuvants did not cause non-target effects in A. caudiglans. The non-ionic surfactant and methylated seed oil increased mortality and decreased reproduction in G. occidentalis. The high toxicity of glufosinate and paraquat for both predators is concerning; these are the primary "burn down" herbicide alternatives to glyphosate, which is decreasing in use due to consumer toxicity concerns. Field studies are needed to determine the extent to which herbicides disrupt orchard biological control, focusing on glufosinate, paraquat, and oxyfluorfen. Consumer preferences will need to be balanced with natural enemy conservation.

Management strategy for pink bollworm (Pectinophora gossypiella) in cotton (Gossypium hirsutum) in farmers-participatory mode

Cotton (Gossypium hirsutum L.) in central India is witnessing increasing infestation of bollworm and sucking pests since 2016. In recent years, pink bollworm, Pectinophora gossypeilla (Saunders) has emerged as a serious problem causing severe damage to cotton in several parts of our country. Farmers rely on chemical pesticides to control pest incidence that adversely affects naturally occurring predators and parasitoids in the crop ecosystems. The study was conducted by ICAR-National Research Centre for Integrated Pest Management, New Delhi during rainy (kharif) season 2018–21 to implement IPM validation trials at Wakhari village of Jalna district, Maharashtra with a view to study the economic viability and feasibility of adaptable IPM technology in farmer participatory mode. IPM implementation significantly reduced the number of insecticidal sprays (49.74%) and increased the cotton yield (28.49%) againstthe farmer’s practice (FP). Benefit to cost ratio was also higher in IPM fields (1.7, 2.4, 2.3 and 3.96) as compared to FP (1.3, 1.5, 1.74 and 2.97) during 2018, 2019, 2020 and 2021, respectively. It was evident that by adopting IPM strategy, pink bollworm in cotton can be successfully managed with minimum application of insecticides along with conservation of natural enemies and higher net return (42.6%) over farmer’s practice. The technology will be helpful in increasing the seed cotton yield and improve quality especially in terms of reduced pesticides contents, thereby improving the socio-economic status of cotton growers of the country.

PRESENCIA DE HONGOS ENTOMOPATÓGENOS ASOCIADOS A SUELOS CULTIVADOS CON AGUACATE (Persea americana Mill.) EN COLIMA, MÉXICO

<p><strong>Background: </strong>Entomopathogenic fungi (EF) play a key role in the regulation of arthropod populations and biotransformation in natural systems, as well as biological pest control agents in different agroecosystems, including avocado cultivation (<em>Persea americana</em> Mill.), where Mexico is a leader in production and export worldwide.<strong> Objective</strong>: Determine the presence of EF in soil in commercial avocado orchards in the state of Colima, Mexico. <strong>Methodology</strong>: Sampling was carried out in three avocado orchards (Piedra rajada, El Guardián, and Montitlán) located in Comala and Cuauhtémoc in the state of Colima, Mexico, from July 2016 to June 2017. Soil samples were collected around avocado trees. Isolation of entomopathogenic fungi was performed using the <em>Galleria mellonella</em> Linnaeus insect trap technique. The isolates were identified considering their micro- and macroscopic characteristics with the taxonomic keys of Humber (2012). <strong>Results</strong>: A total of 108 samples were collected, of those, 120 isolates were obtained, of which 112 belong to the genus <em>Metarhizium</em> and eight to <em>Beauveria</em>. <strong>Implications</strong>: The recovered fungi have a great value for the avocado-growing areas of the state of Colima, either for the conservation of natural enemies of soil pests or for their potential use as an alternative to synthetic insecticides. <strong>Conclusion</strong>: Knowing the native micro-biota of the soil should be considered within biological pest control strategies, since it allows selecting the best adapted species, and including sustainable alternatives for the environment. </p>

Penyuluhan Pengendalian Organisme Pengganggu Tanaman Manggis (Garcinia Mongostana L) Secara Terpadu Pada Kelompok Tani Mukti di Desa Cibuntu Kecamatan Wanayasa Kabupaten Purwakarta

Cibuntu is a mangosteen-producing village. Fluctuations and low mangosteen production are caused by pests. Most farmers have not implemented IPC to the fullest. This extension aims to change and improve the understanding, willingness of farmers and the application of IPM. The target of the extension is the members of the Mukti Farmers Group. The The executors are the POPT field staff of the West Java BPTPH agency. Held since 2020. The extension materials include types of organisms that disturb mangosteen plants, the concept of integrated pest control. Anjangsono counseling methods, lectures, discussions, demonstrations of how to, demonstration of results and installation of banners. As a result of counseling, there is an increase in the number of farmers who know the concept of controlling pests, know how to control opto mangosteen in an integrated manner, about natural enemies and integrated opt control is an efficient way. Farmers who have doubts about the concept of opt and how to control integrated opt and about natural enemies are decreasing in number. There are 13.3% of farmers who still don't know how to do IPM. There is an increasing number of farmers who agree to the conservation of natural enemies, weeding tools is better than with pesticides, destroying diseased crop residues, and not eating and drinking when applying pesticides. There was a decrease in the number of farmers who used inorganic pesticides and left the plants alone and did not wash the remaining pesticide mixture. There was an increase in the number of farmers who washed the remaining pesticide mixture first. There was no change in the number of farmers who washed their body parts affected by pesticides with running water or detergent.

Large-scale IPM validation in whitefly (Bemisia tabaci)-prone cotton (Gossypium spp.) fields adjoining kinnow orchards

Whitefly [Bemisia tabaci (Gen)] is a serious sucking pest of cotton in the north zone of India. Cotton (Gossypiumspp.) fields adjoining kinnow orchards used to have a quite higher incidence of whiteflies compared to the fieldsaway from orchards. Therefore, the study was carried out at ICAR-National Centre for Integrated Pest Management,New Delhi during 2017–19 to implement integrated pest management (IPM) validation trial in cotton fields locatedadjoining the kinnow orchards in the village Nihalkhera of district Fazilka, Punjab in farmers’ participatory (FP). TheIPM strategy consists of weed removal from orchards, timely sowing of recommended cotton hybrid, 4 foliar spraysof 2% potassium nitrate, use of azadirachtin 1500 ppm @5 ml/litre, conservation of natural enemies by avoidance ofinsecticides that are harmful (IOBC Class-4) to natural enemies and judicious use of safer pesticides (IOBC class1and 2). The IPM adoption resulted in the successful management of whitefly and other sucking pests along with atwo to three-fold increase in predator population compared to FP. IPM recorded a substantial reduction in the use of pesticide active ingredients (86%) and the number of sprays (58%) along with high parasitization (35.32–45.98%) of whitefly nymphs by Encarsia sp. IPM provided a significant increase in yield (23%), net return (57.5%) along witha high benefit cost (B:C) ratio of 2.65.

Plants for Fitness Enhancement of a Coffee Leaf Miner Parasitoid

The enhancement of pest control through the conservation of natural enemies in agricultural fields is called conservation biological control. One of the strategies used on this system is to introduce or manage plants that can provide food for natural enemies. We assessed the effect of feeding resources on the fitness of a coffee leaf miner parasitoid, Proacrias coffeae Ihering (Hymenoptera: Eulophidae), by evaluating the effect of different nectar resources on the survival of P. coffeae. To do so we used three flowering plants: Bidens pilosa, Galinsoga parviflora, and Varronia curassavica, and the leguminous shrub, Senna cernua Balb. H.S. Irwin & Barneby which produces extrafloral nectar. When feeding on the floral nectar of V. curassavica and on the extrafloral nectar of S. cernua the parasitoids increased their survival, however, no significant differences were found when feeding on B. pilosa and G. parviflora. We evaluated the effect of extrafloral nectar of S. cernua on the egg load of P. coffeae and found an increase in their egg load when exposed to the extrafloral nectar and with increasing age. Our results show the potential of V. curassavica and S. cernua as nutritional resources to enhance the fitness of the parasitoid P. coffeae, by increasing their survival. Based on the research study, it is evident that the introduction of feeding resources for P. coffeae in the coffee agroecosystem will increase their fitness as a potential biocontrol agent by enhancing their survival and reproductive potential.

Hedgerows have contrasting effects on pollinators and natural enemies and limited spillover effects on apple production

Agricultural intensification has resulted in a decline in insect biodiversity and threatens the provision of valuable ecosystem services. Agri-environment schemes (AESs) have been implemented in an effort to conserve biodiversity on farmland and increase agricultural sustainability, but their effectiveness can vary widely. To better determine which factors influence AES effectiveness, the relative roles of local habitat features, habitat quality, and landscape context need to be further explored. The aim of this study was to determine the most important factors influencing field margin AES effectiveness in commercial apple orchards, in terms of arthropod biodiversity conservation and ecosystem service provision. We surveyed wild bees and aphid natural enemies in field margins and apple trees in 20 orchards, ten bordered by hedgerow field margins (an AES) and ten with herbaceous field margins (no hedgerows present, not an AES). We considered field margin floral resources and the cover of semi-natural habitat in the surrounding landscape as indicators of local habitat quality and landscape context, respectively. We furthermore quantified pollination and pest control as measures of ecosystem service delivery and the relationship between arthropod communities and apple yield (initial and final fruit set) and quality. We found that hedgerow presence strongly predicted both pollinator and natural enemy communities and that these relationships were more pronounced than those with local habitat quality and landscape context. Hedgerows were negatively related to wild bee richness and abundance within the orchard, and positively related to natural enemy richness and abundance at the field margin but not within the orchard. We found no relationships between local and landscape factors and ecosystem service delivery, and no relationship between wild bee communities and apple yield, suggesting that apple is not pollen limited in our study system. There was, however, a negative relationship between natural enemy richness and initial fruit set. We conclude that annually cut hedgerows can benefit the conservation of natural enemies, but have limited arthropod-mediated private benefits for apple production, and likely need to be supplemented with additional local habitat resources for the conservation of wild bees. Our findings indicate that local habitat factors can strongly influence biodiversity regardless of landscape context, but that AESs likely need to be designed with separate biodiversity and ecosystem service targets, and specific taxonomic groups, in mind.

SYNTHESIS AND EVALUATION OF DIFFERENT PEST MANAGEMENT MODULES AGAINST VECTOR AND SUCKING PESTS OF BITTER GOURD

<p class="abstrakinggris">Bitter gourd, <em>Momordica charantia </em>Linn., is one of the most important traditional vegetable in India. Infestations of sucking pests especially jassid, and whitefly occurred thorough out the crop growth period in the region. For ecofriendly management, different pest management modules <em>viz</em>., bio-intensive, chemical, and integrated modules were evaluated against these sucking pests and compared under field conditions during 2019–2021. Among the three tested modules, the integrated pest management (IPM) comprised seed treatment with imidacloprid @ 5–10 g kg<sup>-1 </sup>of seed, installation of yellow sticky traps @ 25–30 ha<sup>-1</sup>, border crop with maize, spraying of azadirachtin 1500 ppm @ 10 ml L<sup>-1</sup>, thiamethoxam @ 1 g 3<sup>-1</sup> L, imidacloprid @ 1 g 12<sup>-1</sup> L, cyantraniliprole @ 1.8 ml L<sup>-1</sup>, neem oil (0.5%) + <em>Lecanicillium lecanii</em> @ 2.5 g L<sup>-1</sup>, and neem oil (0.5%) + <em>Beauveria bassiana</em> @ 2.5 g L<sup>-1</sup> from 20 to 70 days after sowing at 10 days intervals each harboured lowest whiteflies population (0.63 per leaf) with maximum per cent reduction over control of 70.14. The number of predatory lady bird beetles and polyphagous spiders were also higher. The highest healthy fruit yields (171, 179, and 153 q ha<sup>-1</sup>) were recorded from the IPM module for three consecutive years (2019, 2020, and 2021, respectively). In terms of return, maximum net profit of ₹71,211 was obtained from the IPM module with the highest incremental cost-benefit ratio of 1:5.18. Therefore, the IPM module could be a viable ecofriendly option in the management of the sucking pests of bitter gourd, along with the conservation of natural enemies.</p>

Knowledge and Practices of Vegetables Insect Pest Managements in Banganga Municipality of Kapilvastu District

A study was carried out in Banganga Municipality of Kapilvastu district to know the farmer's knowledge, practices, and management method used in insect pests of vegetables. The survey involved 160 randomly selected farmers who were interviewed using semi-structured questionnaires and also evaluated based on direct field observation. The data were analyzed using SPSS and Microsoft-Excel. Tomato, potato, chili, cauliflower, cabbage, garlic, and onion were major vegetables grown by the farmers during the winter season and cucumber, bottle gourd, bitter gourd, sponge gourd, tomato, chili, brinjal during the summer season. Aphids, cabbage butterfly, pumpkin beetle, tomato leaf miner, cutworm, and tomato fruit borer were the major pests in vegetable field. Knowledge of vegetable farmers regarding insect pest identification was also observed i.e., 86% of respondents identified insect pest by the help of Junior Technical Assistance and agro-vets, and 10% of respondents identified insects by their own knowledge. About 60% of respondents were found using chemical pesticides such as; chlorpyrifos, cypermethrin, imidacloprid, alphamethrin etc. to control pests, 4% of respondents were using botanical plant extract i.e., jholmal, neem extract, cow urine and 24% were using cultural methods such as crop rotation, mulching, tillage operation. Only a few farmers' groups were found to know about IPM, biological pest management practices, and conservation of natural enemies.

The abundance of arthropods and natural enemies on two growth phases of hybrid corn, Solok District, Indonesia

Abstract. Hervani D, Sari SP. 2022. The abundance of arthropods and natural enemies on two growth phases of hybrid corn, Solok District, Indonesia. Biodiversitas 23: 2966-2972. Solok District, West Sumatra, Indonesia is one of Indonesia's hybrid corn production regions. As yet, the study of arthropods is still limited. This study aimed to study the abundance and diversity of arthropods in the hybrid maize agroecosystem in Solok District, West Sumatra. The research was conducted from May to November 2020 in Tanah Garam Sub-district, Solok District. The sampling was carried out four times in two growth phases of hybrid corn: vegetative (the age of 20 and 40 days after planting/DAP) and the generative phase (the age of 60 and 80 DAP). The arthropod collection was conducted using a yellow trap and a modified vacuum technique. The identification process was carried out at the Insect Bioecology Laboratory, Andalas University. The study found two classes of arthropods in a hybrid cornfield in Solok District, namely Arachnida and Insecta. The Shannon-Weiner diversity index value (H') was 1.383, and the evenness index of species (J') was 0.997. A total of 2,927 individual arthropods, 80 families, 8 orders, and 3 classes, were recorded in the hybrid corn ecosystem in Solok District. Insect class (2,866 individuals) dominated the diversity of arthropods, where the majority of the arthropods found belong to groups of natural enemies such as predators and parasitoids. Conservation of natural enemies (predators and parasitoids) is one of the main factors in supporting the success of pests biologically, so the act of identifying natural enemies in an area is very important.

Biotechnological Approaches for Host Plant Resistance to Insect Pests.

Annually, the cost of insect pest control in agriculture crosses billions of dollars around the world. Until recently, broad-spectrum synthetic pesticides were considered as the most effective means of pest control in agriculture. However, over the years, the overreliance on pesticides has caused adverse effects on beneficial insects, human health and the environment, and has led to the development of pesticide resistant insects. There is a critical need for the development of alternative pest management strategies aiming for minimum use of pesticides and conservation of natural enemies for maintaining the ecological balance of the environment. Host plant resistance plays a vital role in integrated pest management but the development of insect-resistant varieties through conventional ways of host plant resistance takes time, and is challenging as it involves many quantitative traits positioned at various loci. Biotechnological approaches such as gene editing, gene transformation, marker-assisted selection etc. in this direction have recently opened up a new era of insect control options. These could contribute towards about exploring a much wider array of novel insecticidal genes that would otherwise be beyond the scope of conventional breeding. Biotechnological interventions can alter the gene expression level and pattern as well as the development of transgenic varieties with insecticidal genes and can improve pest management by providing access to novel molecules. This review will discuss the emerging biotechnological tools available to develop insect-resistant engineered crop genotypes with a better ability to resist the attack of insect pests.

The impact of reduced tillage and distance to field margin on predator functional diversity

IntroductionAgricultural intensification results in biodiversity loss through land conversion and management practices which negatively impact arthropods. The abundance and diversity of ground-dwelling predators, e.g. ground beetles (Coleoptera: Carabidae) and spiders (Araneae), are negatively affected by soil disturbances such as tillage. Reducing soil disturbances can potentially conserve arthropod populations in the field and reduce the use of chemical pest controls. The present study investigated the ground-dwelling predatory community using pitfall traps in cereal fields with three different levels of soil disturbance: conventional tillage, reduced tillage and no tillage under Conservation Agriculture management, in 2018 and 2019. Pitfall traps were placed in transects from the field margins. Overall, the activity-density of ground-dwelling predators was higher in fields with minimum soil disturbance and generally declined with increased distance to semi-natural habitats. Functional diversity, expressed by the body size of ground beetles, was also affected by soil disturbances; large ground beetles more consistently occurred in CA, while few or none of the largest ground beetles were found in RT and CT. A higher sample-heterogeneity in less disturbed fields was indicated by a more variable median and higher skewness in the number of predators in those fields. In 2019 only, species diversity was higher along field edges bordering semi-natural habitats when compared to the cropped area. Our results show that reduced tillage supports predator arthropod communities at a local scale: It also bolsters agro-ecosystem resilience by promoting a higher activity-density and by increasing the heterogeneity and functional diversity of ground-dwelling predators.Implications for insect conservationThe results obtained in the present study show that soil disturbances significantly influence arthropod abundance and diversity. Conservation of epigeic natural enemies in the agricultural landscape is improved by reducing soil-disturbing events such as tillage.