Yellow Pan Research Articles

Diversity of Hymenoptera parasitoid on oil palm (Elaeis guineensis Jacq.) plantations in Dharmasraya District, West Sumatra Province

Oil palm farmers in Dharmasraya District always strive to increase oil palm production and productivity. The biotic factors can affect the presence of Hymenoptera insects. Most of the Hymenoptera insects are parasites. The research aimed to study the diversity of Hymenoptera parasitoids in oil palm plantations in young oil palm plantations (2-3 years old) and older oil palms (5-20 years old) in Dharmasraya District. Sample points were determined using the transect line method on the land. Sampling was carried out using three traps: 1) yellow pan traps, 2) malaise traps, and 3) Sweep net. The analysis was carried out by calculating the Shannon-Wiener diversity index (H’), the Margalef species richness index (D), the Pielou species evenness index(J), the Jaccard similarity index (Is), and the estimated species richness of Hymenoptera parasitoid. Hymenoptera parasitoids found at the research sites were 1,267 individuals consisting of 23 families and 142 morphospecies. Two young oil palm plantations have a higher diversity of Hymenoptera parasitoids (4.15; 4.24) than older oil palm plantations (3.51; 3.86). The Braconidae, Ichneumonidae, and Scelionidae families dominated the abundance of Hymenoptera parasitoids. Young oil palm plantations have a higher diversity of Hymenoptera parasitoids than older oil palm plantations.

Struktur Komunitas Artropoda di Pembibitan Kelapa Sawit

Nurseries are one of the essential agronomic activities in oil palm cultivation. Oil palm seedlings are cultivated on a large scale, different from nurseries for other plantation commodities. The nursery expanse comprises various biotic components, one of which is Arthropods. This study aims to determine the Artropod community and its function in oil palm nurseries. The research was carried out at two nurseries, Nagari Gunung Medan and Nagari Kurnia Selatan, Dharmasraya Regency, West Sumatra Province. Sampling using the pitfall trap, yellow pan trap, insect nets, and direct collection methods. The results showed that the Arthropods that make up the oil palm nursery ecosystem were insects and spiders. Arthropods in oil palm nurseries act as phytophages, predators, parasitoids, and detrivores. Phytophage insects found in oil palm nurseries were 700 individuals consisting of 4 orders, nine families, and 14 genera/species. Predatory insects, parasitoids, and detritivores were found in as many as 466 individuals consisting of 5 orders, 14 families, and 16 genera/species. There are two species of spiders in oil palm nurseries: Pardosa sp and Oxyopes javanus. Valanga sp was the species with the highest number of individuals in oil palm nurseries.

Crop-Specific Effects on Pan-Trap Sampling of Potential Pollinators as Influenced by Trap Color and Location

Characterizing insect communities in pollinator-dependent crops helps determine the potential pollinator effectiveness and their effects on crop yield. Few studies have examined pollinator communities and their services to crops in South America. Furthermore, optimal sampling methods for these communities in the crop habitat have received little attention. Pan traps are one of the simplest and most widely used sampling methods to assess insect diversity. We compared different pan trap arrangements to describe potential pollinator communities in two commercial crops (blueberry and canola) in Southern Chile. We compared communities in the crops and assessed how sampling position (border or center) and pan trap color (blue, white, or yellow) affected sample composition. Species composition was significantly different between crops. Furthermore, trap color affected sample composition in blueberry, but trap position did not, whereas color had no significant effect on canola, but trap position did. In all cases, yellow pans captured the largest number of species. Hymenoptera explained most of the differences in sampling efficiency because of the differential responses across species. We suggest that pan trap assessments of the diversity in potential pollinator insects depend on crop characteristics, including planting configuration and floral morphology. Therefore, comparative studies should include pans of different colors positioned at various locations within the crop.

Diversity of hymenopteran families associated to quinoa crop in Algeria (case of Biskra province)

<p class="042abstractstekst"><span lang="EN-US">The quinoa (<em>Chenopodium quinoa</em>Willd.) crop is originated from Andean region (South America). Its nutritional values as well as its drought climate and water salinity tolerant character have motivated many countries such as Algeria to adapt such a plant culture. This study aims to assess entomofauna from Hymenoptera order in terms of composition and functional diversity. We aim also to evaluate the consequences of the expansion and uncommon crop on the hymenopteran composition. For the first field trial, the survey was carried out in Biskra province during 2018-2019. The Shannon Wiener index and evenness indices were used to measure family’s diversity. The results revealed that 1737 specimens were identified into forty families and 166 species. Formicidae species were the most abundant with 68 % of total number of individuals, followed by Braconidae with 7 % and Crabronidae with 5 %. As well, diversity collected with yellow pan traps was more important in winter and spring seasons. As the functional groups, results indicated the presence of three major groups; parasitoids, pollinators and predators. The parasitoid group is the richest one.</span></p>

Species Diversity and Dominance of the Aranaemorphae Sub-Order in the 90-Day-Old Rice Generative Phase

Spiders have an important role in ecosystems, in particular agricultural ecosystems. Spiders play the role of natural enemies capable of helping farmers by eating insect pests. The purpose of this study was to identify the type of Sub-Order Aranaemorphae and calculate the level of diversity and dominance of the type of Sub-Order Aranaemorphae in the generative phase of rice aged 90 days. The study was conducted in April-September 2022 in the rice field area of Tamanan Village. The determination of the research location was carried out using the purposive sampling method with the criteria of a rice field area of 2500 m2 and the age of rice plants ranging from 90 days. Sampling was carried out on 9 plots with a plot size of 21 x 4 m2 each. Sampling was carried out by hand picking and indirect methods with sweep nets, pitfall traps, and yellow pan traps. The species of Sub-Order Aranaemorphae found in this study were 12 species, namely Oxyopes sp., O. lineatipes, O. javanus, Atypena formosana, Tetragnatha vermiformis, Pardosa pseudoannulata, Lycosa sp., L. pseudoannulata, Lycosa sp. 1, Araneus inustus, Clubiona sp. and Thomisus Sp. The conclusion of this study were the diversity index value (H') of the Aranaemorphae Sub-Order obtained in this study was 2.133 with a moderate category, and the dominance index value (D) of the Aranaemorphae Sub-Order obtained was 0.1785 with a low category. The total number of spider individuals obtained was 173 individuals.

Abundance and diversity of predatory insects in chili plant ecosystems cultivated by IPM

Cayenne pepper is a strategic commodity. The use of chemical insecticides to control pests has a negative impact on the agroecosystem. Integrated Pest Management (IPM) is an environmentally solution to overcome pest problems. The objectives of this study were to determine the abundance and diversity of predatory insects. Sampling was carried out in August-October 2020 in west Lombok, Indonesia, on chili fields using the IPM technique. Observations were conducted on the generative phase of chili planting and carried out using the Yellow Pan and Pitfall Trap. The population of predatory insects in chili with IPM was 1,707 individuals representing 24 species from 8 families and 5 orders. The order Hymenoptera was the most abundant (63.27%) of the total predatory insects collected, followed by Coleoptera (30.93%), and Diptera (4.63%). The diversity index of predatory species is 1.79 in land planted with chili using IPM techniques. Chili plant using IPM techniques has more abundance and divers of predatory insect species than conventional chili land. This study provides some insight into the community of predatory insects in the generative phase of the chili ecosystem and suggests that an ecological approach is needed for pest management to maintain the balance of the agroecosystem and promote biodiversity.

A comparison of sampling methods and temporal patterns of arthropod abundance and diversity in a mature, temperate, Oak woodland

Arthropods underpin fundamental ecological processes such as herbivory, pollination and nutrient cycling, and are often responsive to subtle changes in environmental conditions. Thus, changes in their abundance and phenology may be crucial indicators of system-wide responses to climate change.The new Birmingham Institute for Forest Research (BIFoR) Free Air Carbon Dioxide Enrichment (FACE) facility provides a unique opportunity assess arthropod diversity and abundance in mature deciduous forest and the effect of sampling method and seasonality. This is an essential first step before attempting to measure the potential impacts of climate change, such as elevated CO2, on arthropod populations. Two fundamental criteria are: i) diverse sampling methods in order to effectively assess diversity and in particular, differences between structural layers of the woodland system, e.g., ground, sub-canopy and canopy layers, ii) a temporal resolution that can identify seasonal patterns of change (phenology). This paper sets out the methodological approaches employed to achieve these objectives.A total of 22,568 invertebrates from 108 families were sampled across 12 months of continuous sampling using a range of techniques from forest floor to canopy. Diptera were the most abundant order sampled and had the greatest number of families represented (45). Phenology patterns generally followed the anticipated seasonal cycle, with increasing abundance and diversity from spring to summer. Temperature was the best environmental predictor of abundance within Malaise and pitfall traps. Precipitation was not correlated with any monthly patterns of trap data. Yellow pan traps collected more arthropods than white or blue traps. Canopy beating yielded a greater diversity than that in the understory samples.These data provide an important baseline from which to assess any future impacts of eCO2 over the 10-year BIFoR FACE experiment, and highlight the importance of employing diverse sampling methods, temporal replication and measuring environmental factors over appropriate timescales.

Karakteristik Komunitas Serangga Pengunjung Bunga Pada Beberapa Tanaman Refugia

This study was conducted to determine the characteristics of the insect community of flower visitors on several refugia plants. The research was carried out in the experimental field of the Faculty of Agriculture, Jambi University and the Laboratory of Plant Pests, Faculty of Agriculture, Jambi University. Samples of flower-visiting insects were taken using the yellow pan trap, pitfall trap, and sweep trap. The insects obtained were identified in the Laboratory of the Faculty of Agriculture, Jambi University. Characteristics of insect communities in refugia plants were calculated using the formulas of diversity index, similarity index, dominance index, and similarity index. The results showed that the abundance of species and populations of insects was most commonly found in Zinnia elegans flowers. Most predatory insects were found in Z. elegans flowers, pollinator insects were most abundant in Helianthus annuus flowers, and pollinators were most abundant in Z. elegans flowers. The characteristics of the insect community in the most stable refugian plant were found in Tagetes erecta flowers. The highest similarity of insect communities was found in Cosmos caudatus flowers and Impatiens balsamina flowers.

DIVERSITY OF PREDATOR AND PARASITOIDS INSECTS ON SEVERAL TYPES OF OIL PALM PLANTATION ECOSYSTEMS

Both oil palm plantations boerdering forests and oil palm plantations bordering rubber plantations were studied using purposive random sampling with pit fall traps, sweep nets and yellow pan traps. Species biodiversity was analyzed using the Shanon-Wienner index and the Simpson index. The dominant species was determined using the Important Value Index. This study found 1,683 individuals, 7 orders and 18 families of predatory and parasitoid insects. The Shanon-Wienner diversity index was 2.78 for oil palm plantations adjacent to forest and 2.62 for oil palm plantations adjacent to rubber plantations. While the Simpson diversity index was 1.00 for oil palm plantations adjacent to forest and 0.94 for oil palm plantations adjacent to rubber plantations. The Order Hymenoptera Family Formicidae had the highest Important Value Index (0.58 for oil palm plantations bordering forest and 0.62 for oil palm plantations adjacent to rubber plantations).

Natural Enemies of Pest in Rice Cultivation of Sesayap Watershed Area, Tana Tidung Regency

Study of potency natural enemies are base for utilization as a natural control of pests. This study was determined the main of natural enemies on rice cultivation in several site in Sesayap watershed area, especially Tana Tidung Regency. The study sites were collected in Tideng Pale, Gunawan, Sesayap Hilir, Rian, and Tana Merah. Each site was sampled at 5 points using traps, sweep net, and yellow pan traps. The results showed insect group consisted of 32 families, 44 genera, 44 species and 836 individuals. The Araneae group were consisted of 11 families, 12 genera, 13 species and 347 individual species. Insect predatory have highest number which were Dolichoderus taschenbergi (24.7%), Chlaenius nigricans (19.9%), and Anoplolepis gracilipes (17.8%). The Shanon-Wiener species richness and diversity index, and the evenness index in Rian (R=5.93; H’=2.77; E=0.79), Bandan Bikis (R=3.63; H’=2.16; E=0.75), Tana Merah (R=6.48; H’=2.16; E=0.62), Tideng Pale (R=6.48; H’=2.90; E=0.79), and Gunawan (R=5.86; H’=2.73; E=0.76) respectively. The Tideng Pale and Rian have the highest similarity index (67%), while the lowest index at the Tana Merah and Tideng Pale sites (44%). Natural enemies of predators tended relationship with Gunawan and Rian site. Meanwhile, site of Bandan Bikis tended relationship for enemies of parasitoids. Based on these results, the Sesayap watershed of Tana Tidung Regency has a high species richness, but the diversity is classified as moderate. Thus, it is necessary to make efforts to conserve natural enemies of pests in the Sesayap watershed area, Tana Tidung Regency.

Differences in functional trait responses to elevation among feeding guilds of Aculeata community.

The response of communities to environmental change is expected to vary among feeding guilds. To evaluate the response of guilds to environmental factors without considering the taxonomic specificities, it is useful to examine Aculeata bees and wasps, which consist of closely related taxa including different guilds, pollinators, predators, and parasitoids. In this study, we evaluated changes in species diversity (SD) and functional traits of each feeding guild along an elevational gradient in a boreal forest in northern Japan. We used yellow pan traps to collect Aculeata bees and wasps at 200–1600 m above sea level. We investigated six functional traits (trophic level, seasonal duration, body size, elevational range, nesting position, and soil dependency) and the horizontal distribution of the species. The SD of all Aculeata, predators, and parasitoids decreased with an increase in elevation; however, the SD of pollinators did not show any specific trend. Although the functional trait composition of all Aculeata species did not show any trend, that of each feeding guild responded to elevation in different ways. Pollinators increased in body size and showed a decrease in seasonal duration with increasing elevation, suggesting that tolerance and seasonal escape from physical stress at high elevations are important for shaping pollinator communities. Predators increased their elevational range and the proportion of above‐ground nesting species increased with increasing elevation, suggesting that the ability to live in a wider range of environments and avoid unsuitable soil environments at high elevations might be important. Parasitoids changed their hosts and displayed variable traits with increasing elevation, suggesting that brood parasitoids have difficulty in surviving at high elevation. The traits for each guild responded in different ways, even if they were dominated by the same environmental factors. Our findings imply that differences in the responses of functional traits would produce different community assembly patterns in different guilds during further climate change.

Agroecosystem complexity of Surjan and Lembaran as local farming systems effects on biodiversity of pest insects

Abstract. Trisnawati DW, Nurkomar I, Ananda LK, Buchori D. 2022. Agroecosystem complexity of Surjan and Lembaran as local farming systems effects on biodiversity of pest insects. Biodiversitas 23: 3619-3629. Farming systems can influence the diversity and abundance of insect pests. This study was conducted to determine the effect of Surjan and Lembaran farming systems on the diversity and abundance of insect pests in Kulon Progo, Yogyakarta. The field survey was conducted in three Surjan paddy fields and three Lembaran paddy fields in Panjatan Subdistrict, Kulon Progo Regency. The sampling of pests was collected using four kinds of traps, such as sweeping net, yellow sticky trap, pitfall trap, and yellow pan trap. The traps were set twice in the vegetative phase and twice in the generative phase. The results showed that the abundance of pests in Surjan paddy fields was not different from that in Lembaran paddy fields. However, the number of pest species in Surjan paddy fields was higher than in Lembaran paddy fields. In addition, the structure and composition of pests in both farming systems were significantly different. Hemiptera was the most common insect in both farming systems, with dominant pest species of Nephotettix virescens and Nilaparvata lugens.

Tree Diversity Enhance Species Richness of Beneficial Insect in Experimental Biodiversity Enrichment in Oil Palm Plantation

Integrating plantation landscape with vegetation/tree diversity has been proposed as a strategy to maintain crop production (for livelihood) while increasing biodiversity, habitat complexity and ecological functions. The objective of this research was to investigate the influence of tree biodiversity in experimental biodiversity enrichment in oil palm plantation to beneficial insects, especially ants and parasitoid wasps in the EFForTS-BEE research plot. Beneficial insects in experimental enrichment oil palm plantation are very important to be studied so that ecosystem services that are related with the changes of the plant structures over time can be understood better. Insect collections were done in two years, 2018 and 2019. Direct sampling was used to collect actual insects, pitfall traps to trap ground dwelling insects, yellow pan traps and malaise trap to trap low-flying insects, and sweep net to collect general insects. Overall, we collected 76 species of 6423 individual ants, and 174 morphospecies of 867 parasitoid wasps in this research. Abundance of ants and parasitoid wasps were not influenced either by tree diversity level in the plot nor the various plant diversity. In contrast, tree diversity level has strongly influenced species richness of ants and partially affected species richness of parasitoid wasps. In conclusion, there are positive correlation between ants’ and parasitoid wasps’ species richness and vegetation abundance.

First record of the genus Scelio (Hymenoptera: Platygastridae, Scelionidae, Scelioninae) egg parasitoids in tomato greenhouses of southeastern Algeria

This is the first record of genus Scelio (Latreille, 1805) in Algeria. Two species of Scelio poecilopterus (Priesner, 1951) and Scelio vulgaris (Kieffer, 1908), were collected in tomato greenhouses from El Alia and El Hadjeb regions in the province of Biskra, southeastern Algeria in 2019-2020, using yellow pan traps, yellow bottles and Barber traps for sampling specimens, followed by laboratory methods to preserve and identify the samples. Photographic material and information on these species are presented and described, on female specimens, in order to expand the knowledge about the distribution and biodiversity of egg parasitoids in our country.

The Distinctive Plant and Insect Assemblages of An Experimental Forest in Northern Lower Michigan (United States).

The effects of plants on insects are not completely clear due to potential covariation of weather or location affecting both assemblages. To address this question, plant and insect assemblages were described during summer 2019 and 2020 in two different forest habitats of northern Lower Michigan. The first habitat was a hardwood forest typical of secondary succession in the region. The second was a hydric forest located ~20 m from the hardwood forest which developed after lake sediment was deposited into a 10-ha area in the early 2000s. Reflecting this sediment deposition, soil of the hydric forest had higher water content and organic matter, and was dominated by the plant genera Solidago (Asterales: Asteraceae), Rubus (Rosales: Rosaceae), and Salix (Malpighiales: Salicaceae). In contrast, the hardwood forest had greater inorganic sediment and was dominated by Pteridium (Polypodiales: Dennstaedtiaceae), Carex (Poales: Cyperaceae), and Acer. Nearly 140,000 insect specimens were sampled using pitfall trapping, sweep netting, flight intercept trapping, ultraviolet light trapping, and yellow and blue pan trapping. The first three methods each sampled a unique insect assemblage, whereas the last three overlapped in taxa sampled. Insect assemblages of the two forests were distinct from each other using any of the six methods, with abundance of Pteridium and Salix (Sapindales: Sapindaceae) generally associating with changes in insect composition. A total of 41 insect taxa indicated the hydric forest and 14 indicated the hardwood forest. Insect richness increased with that of plants. These results demonstrate that differences in soil composition and plant assemblages associate with differences in forest insect assemblages, even of forests in very close proximity.

The Spring Insects Diversity in Mutis Timau Nature Reserve

Insect diversity is believed to be used as a bio-indicator of spring quality. This study aimed at determining the spring insect diversity around the Mutis Timau Nature Reserve. The study was conducted from June to August 2019. Insects were caught by using the yellow pan trap and hand sorting. The diversity of spring insects was determined based on the Shannon-Wienner diversity index (H'), species richness index (R1), species dominance index (D), and evenness index (E). The results showed that 16 species belong to 11 families, and 5 orders of insects. The families included Gryllidae, Gryllotalpidae, Tetrigidae, Formicidae, Pompilidae, Apidae, Ochteridae, Veliidae, Hydrometridae, Nepidae, Coenagrionidae, Libellulidae, Carabidae, and Coccinellidae. The Shannon-Wiener species diversity index and the wealth index of the species of springs were classified as moderate (H '= 2.12 and R1 = 4.19). There was no type of spring insects dominated (D = 0.23). All springs insects were found to have almost the same level of evenness (E<1), with a value of 0.76. Abiotic factors such as pH and soil temperature were within the tolerance range of spring insects.
 
 Key words: Insects diversity, Spring, Mutis Timau Nature Reserve

Diversity of Ant Species (Hymenoptera: Formiciidae) in Flower Plants Combination on Ratoon Sugarcane

This research aims to examine the effects of several refugia plant treatments on the diversity and number of ants in the ratoon sugarcane system. The diversity and abundance of ants in the plantation's surrounding habitats can fluctuate. Three combinations of flowering plants were used in the study: Turnera subulata Sm (Malpighiales: Passifloraceae), Cosmos sulphureus (Asteraceae: Asteraceae), and Zinnia elegans Jaqc (Asterales: Asteraceae). Ant samples were collected using yellow sticky traps and traps and yellow pan traps. R. software was used to examine all of the data. 4 subfamilies, 14 genera, and 25 species: Diacamma sp., Technomyrmex sp., Camponotus sp.1., Iridiomyrmex sp., Delichoderus sp., Leptogenys sp.; Odontomachus sp., Polyrachis sp., Pheidole sp., Tetramorium sp., Monomorium sp., Crematogaster sp., Oecophylla smaragdina was identified from the report's results, this included 1-86 individuals. Tetramorium sp. and Odonthomachus sp. were the most common ants found at the study site. Even before compared to the other treatments, the combination of refugia and Z. elegans, C. sulphureus, T. subulata treatment used to have a significant impact on the presence of ants, increasing the population by 21%. This study discovered that combining refugia could increase ant diversity in ratoon sugarcane. The diversity index value for all treatments was almost the same, in the range of 2.-9-2.82, indicating that the main composition of refugia was moderately diverse.

Biodiversity and community structure of Arthropod in tropical rice fields under organic and conventional ecosystems

The practice of conventional rice cultivation using inorganic fertilizers and synthetic chemical pesticides can affect the stability of ecosystems. This study aimed to compare the diversity and community structure of arthropods in tropical rice field under organic and conventional ecosystems. This research was conducted at Oloboju, located at an altitude of 120 m above sea level. The soil type was inceptisol. The research used observation and exploration methods. The sampling of arthropods in the field used a sweep net, a pitfall trap, a yellow pan trap and by hand. The variables measured were the taxonomic composition and relative morpho-species abundance, family and order composition. Relative morpho-species abundance was assessed based on functional roles, number of species, and the total number of individuals. The results show that the Shannon diversity index value (H') and Margalef richness index (Dmg) were higher in organic rice ecosystems than conventional. On the other hand, the organic rice ecosystem had a Simpson dominance index value (C) and an evenness index (E) lower than the values of C and E in conventional rice ecosystems. The organic ecosystem had a community structure of arthropod of 9 orders, 24 families, and 28 morpho-species, with an abundance of 4,002 individuals, while the conventional ecosystem had a community structure of arthropod of 7 orders, 17 families, and 20 morpho-species with an abundance of 1,789 individuals. The practice of organic rice cultivation would increase the biodiversity index towards ecosystem balance so that it could be used as an alternative to pest control

Diversified and monoculture, contrasts in some parasitoids community of coffee crop / Monocultura diversificada e monocultura, contrastes em alguns parasitóides da comunidade da cultura do café

The diversification of the agriculture is a practice that is getting focus in the last decade, but it always was the natural way. The diversification, being anthropomorphic or natural, brings benefits to the crop, farmer, and the environment. One way possible to restore the diversity of the crop, is planting trees along the culture. Doing this, we can restore the diversification and help to improve ecological function, as pest control. This work was conducted at Fazenda da Lagoa, Santo Antonio do Amparo municipality, Brazil in a coffee plantation diversified with different tree species, being them Avocado, Macadamia, Mangium, Teak and Red Cedar. The insects were collected utilizing yellow plastic pan traps left in the field for a 48h period. Each tree species was sampled separated and a monoculture coffee as control. We found 254 insects in 40 species being 22 species of Braconidae, six species of Eulophidae and 12 Mymaridae species. Our results showed that all tree species had a greater insect richness than Monoculture coffee with Avocado (16), Mangium (18), Cedar (16), Macadamia (19), Teak (16) and Full Sun (10), also we found more abundance of parasitoids at the diversified coffee than in monoculture.

Diversity of Natural Enemies in Corn - Soybean Intercropping with Different Plant Compositions

Intercropping is one of the polyculture crop cultivation techniques. Polyculture cropping system can increase the diversity of insects. This research aims to determine the effect of different plant composition of soybean and corn on the diversity and abundance of natural enemies. This research was carried out using a single factor experimental method arranged in a single plot field design. The treatment tested was the plant composition of soybean and corn which consisted of 4 compositions setting as treatment i.e., 2:1, 3:1. 4:1 and 5:1. In addition, monoculture soybeans and monoculture corn were also planted for comparison. Observation and sampling of natural enemies were carried out using insect sweeping net, yellow pan trap, and pitfall trap. Samplings were done 7 times when the plant at 2, 3, 4, 6, 8, 10, and 12 weeks old. The results showed that the plant composition of soybean and corn affected the number of species and abundance of insect natural enemies. Nonmetric multidimensional scale analysis shows that there are less differences in the composition of insect natural enemies between different plant compositions.