Trap Crop Research Articles

Molecular insights into Solanum sisymbriifolium’s resistance against Globodera pallida via RNA-seq

BackgroundThe presence of potato cyst nematodes (PCN) causes a significant risk to potato crops globally, leading to reduced yields and economic losses. While the plant Solanum sisymbriifolium is known for its resistance to PCN and can be used as a trap crop, the molecular mechanisms behind this resistance remain poorly understood. In this study, genes differentially expressed were identified in control and infected plants during the early stages of the S. sisymbriifolium - G. pallida interaction.ResultsGene expression profiles were characterized for two S. sisymbriifolium cultivars, Melody and Sis6001, uninfected and infected by G. pallida. The comparative transcriptome analysis revealed a total of 4,087 and 2,043 differentially expressed genes (DEGs) in response to nematode infection in the cultivars Melody and Sis6001, respectively. Gene ontology (GO) enrichment analysis provided insights into the response of the plant to nematode infection, indicating an activation of the plant metabolism, oxidative stress leading to defence mechanism activation, and modification of the plant cell wall. Genes associated with the jasmonic and salicylic acid pathways were also found to be differentially expressed, suggesting their involvement in the plant’s defence response. In addition, the analysis of NBS-LRR domain-containing transcripts that play an important role in hypersensitive response and programmed cell death led to the identification of ten transcripts that had no annotations from the databases, with emphasis on TRINITY_DN52667_C1_G1, found to be upregulated in both cultivars.ConclusionsThese findings represent an important step towards understanding the molecular basis underlying plant resistance to nematodes and facilitating the development of more effective control strategies against PCN.

Attract and kill: testing the potential of an entomopathogenic fungus to convert a trap crop into a dead-end trap crop against a soil-borne pest of vegetables

Attract and kill: testing the potential of an entomopathogenic fungus to convert a trap crop into a dead-end trap crop against a soil-borne pest of vegetables

Modeling the effects of trap crop attraction strength, patch dispersion, and biological control on pest suppression

Modeling the effects of trap crop attraction strength, patch dispersion, and biological control on pest suppression

What do Lygus like? Looking for potential trap crops to reduce faba bean damage

Grain legumes, such as faba bean (Vicia faba L.), are crucial for protein supply and soil fertility enhancement through nitrogen fixation. However, faba bean cultivation is challenged by Lygus plant bugs (Hemiptera: Miridae), which cause significant crop damage and seed quality loss. This study aimed to evaluate Lygus preferences between faba bean and alternative crops to develop effective management strategies. We conducted choice bioassay experiments under laboratory conditions and field plot experiments. Laboratory results indicated sex-based host preferences, with males favoring faba beans and females preferring canola. Field studies showed that faba beans adjacent to canola had higher Lygus abundance and damage compared to those next to peas, flax, and safflower. Safflower and sunflower demonstrated potential as trap crops to reduce Lygus damage to faba beans. Our findings provide insights into Lygus behavior and suggest that a combination of trap cropping, and targeted insecticide use could mitigate the impact of Lygus infestations on faba bean cultivation.

Advances in trap cropping

Advances in trap cropping

Attraction of Nicotiana benthamiana to Bemisia tabaci is related to a chemical signal in plant volatile, undecane.

The whitefly Bemisia tabaci is one of the world's foremost agricultural pests. Recently, we found that a wild relative of tobacco (Nicotiana benthamiana) demonstrates remarkable attractiveness and nearly 100% lethality towards whiteflies. Therefore, it can act as a dead-end trap crop for whitefly control in the field. However, the underlying mechanism of the significant attractiveness of N. benthamiana towards whiteflies is unclear. Binary-choice assays and olfactory experiments showed that compared to common tobacco (N. tabacum), the volatile of N. benthamiana has a greater attraction to whiteflies. Then we analyzed and compared volatiles from these two Nicotiana species by thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS). We identified 16 chemical compounds that are more abundant in N. benthamiana than in N. tabacum. Seven compounds were further tested with olfactometer assays and we found that, among them, undecane strongly attracted whiteflies. Further experiments revealed that even 0.005 μg mL-1 undecane is attractive to whiteflies. We also silenced the genes that may influence the biosynthesis of undecane and found the production of undecane decreased after silencing NbCER3, and that N. benthamiana plants with less undecane lost their attraction to whiteflies. In addition, we found that applying 0.005 μg mL-1 undecane on yellow sticky traps can increase the number of stuck insects on the traps by ≈40%. Undecane from the volatile of N. benthamiana is a critical chemical signal that attracts whiteflies and NbCER3 involved in the biosynthesis of undecane. Undecane may be used to improve the efficiency of yellow sticky traps for whitefly control. © 2024 Society of Chemical Industry.

Nematode Diversity and Root-Knot Nematode Management Approaches for Sustainable Mulberry Production

Mulberry ecosystems are beset by the clandestine menace of nematodes, precipitating devastating consequences on plant productivity. This review highlights the importance of nematode diversity in mulberry ecosystems and explores various eco-friendly and sustainable approaches for managing the root-knot nematode, Meloidogyne incognita involving cultural, biological and host resistance methods. Various eco-friendly management strategies viz., cultural approaches like summer deep ploughing, mulching and trap crops; biological methods like bio-agents and plant extracts; and resistant varieties against the root-knot nematode infecting mulberry are reviewed and discussed providing an impetus for integrating multiple approaches for effective and sustainable root-knot nematode management.

Pest trap and natural enemy nursery merged in Lobularia maritima?

Planting crops to push or pull pests from a main crop and floral enhancements to attract natural enemies are emerging as pivotal agroecological strategies to shift away from synthetic pesticides. The brassica, Lobularia maritima, has great potential to act as a floral enhancement as it is attractive to many insects and improves the fitness of and biocontrol services provided by multiple natural enemies. It has been mainly deployed as an insectary plant; few studies have been conducted on its use as a trap plant. We explored the potential of L. maritima as a targeted flower enhancement in sheltered cropping systems through three case studies: (1) as flower strips alongside a cucumber crop, (2) as flower strips alongside a strawberry crop in a replicated on-farm experiment, and (3) as hanging pots under strawberry cultivation gutters. We monitored beneficial and pest insects in flowers and crops and assessed crop damage. Lobularia maritima stands out as an excellent floral enhancement plant due to its ease of cultivation and its ability to flower consistently over an extended period. Generalist predatory bugs, such as Orius laevigatus and Macrolophus pygmaeus, had higher densities on L. maritima than on other flowers grown next to strawberries. We found more thrips on L. maritima and less thrips on crops in two out of three experiments, compared with controls. Further research is needed to confirm if L. maritima is an effective trap crop for thrips and other pests and to detect possible dis-services, such as the attraction of phytophagous bugs.

Intercropping of African Marigold with Tomato for Better Productivity, Pest Control and Economic Returns in Arunachal Pradesh, India

The present study highlights about intercropping of African marigold with tomato for better productivity, pest control and economic returns in Arunachal Pradesh, India. This study was carried out during Rabi season of 2017-18 and 2018-19 respectively in Tirap district of Arunachal Pradesh to find out the best line combination of marigold with tomato. Total three treatments were planted with three replications under Randomized block design. T1 recorded minimum infestation of tomato fruit borer (5.47 %), maximum fruit yield (16.32 t/ha), maximum net return (Rs. 1,53,000), Best B:C ratio (3:1) while T3/control recorded least (18.32%, 14.27 t/ha, rs.1,17,780 and 2:43 respectively). It can be suggested to farmers of Arunachal Pradesh that marigold can be used as a trap crop in tomato farming for better production, yield and economics.

Field Evaluation of Integrated Pest Management Strategies against Chilli Black Thrips Thrips parvispinus (Karny), in the Srikakulam District

Chilli (Capsicum annum L) is an important spice crop grown extensively in India for both domestic and export markets. Invasive black thrips Thrips parvispinus has been causing destructive damage to chilli crop in India leading to indiscriminate use of insecticidal sprays. On-farm trials were conducted during Kharif and Rabi 2022-23 & 2023-24 to evaluate Integrated Pest Management practices against black thrips with emphasis on minimal pesticidal sprays with different mode of actions so that pests may not develop resistance which will reduce the residues on the produce in the farmer’s fields of Srikakulam district of Andhra Pradesh. IPM adopted fields i.e. seed treatment, marigold as trap crop, erection of blue sticky traps, Beauveria bassiana spray and Neem oil and Fipronil 5 SC spray at 30 DAT; Imidacloprid+Fipronil 40%WG spray at 50 DAT; have shown 40 to 85 per cent reduction in black thrips infestation over farmers practice during all the seasons of both the years. This resulted in a higher average mean yield of 57 q/ha, average net returns of Rs. 4,96,000 per hectare with cost benefit ratio of 3.29 in IPM fields over farmer’s practice depicting that the adoption of IPM practices helped in reducing the pest incidence and increase in yield, net returns.

Edible Insects: Nutritional, Medicinal and Allergenic Aspects

Edible insects are a natural food resource that provides nutritional, economic, and ecological benefits to many ethnic and tribal communities of Northeast India. Because of the warm and humid atmosphere, entomophagy is popular culturally and spiritually in tropical and subtropical countries. Many insects, such as lepidopterans, orthopterans, dictyopterans, isopterans, and hymenopterans are all considered common food sources. They have high nutritional and medicinal value that can contribute to food security, health promotion, and environmental sustainability. Natural enemies of pests may include various organisms like predators, parasitoids, pathogens and trap crops. However, they also have some health implications and allergenicity that need to be addressed by scientific research, regulatory policies, and public education. This article aims to explore the nutritive and medicinal paradigm of edible insects of northeast India and examine their health implications and allergenicity. It will review the existing literature on the topic and provide recommendations for future research, policy development, and consumer education.

Evaluation of host plant species for a trap cropping strategy in integrated pest management of pineapple mealybug (Dysmicoccus brevipes)

Pineapple mealybugs are responsible for the emergence of pineapple wilt disease and the subsequent transmission of the pineapple disease virus. This study aimed to evaluate the alternate host plants as potential trap crops for pineapple mealybug. A total of nine host plant species, banana, pumpkin, roselle, hibiscus, ground fig, okra, java grass, goose grass and rhodes grass were selected for the study. Thirty adult females of pineapple mealybug were reared on a pumpkin for two months. Three replicates of a plot (area covered with black netting measuring 3 m × 3 m) were set up. Nine host plant species, approximately 2–3 feet in a 16 inch × 16 inch polybag were arranged in a circle around the pumpkin. The effectiveness of the host plant species was determined by calculating the infestation of each plant species for six months (with two-week observations). Our findings revealed that the pineapple mealybug prefers banana with the greatest mean and SD value (621.7±172.7), followed by pumpkin (237.0±45.6) and the lowest one is rhodes grass (2.00±26.5). ANOVA results show that there is a significant difference between host plant species (F-value of 26.87 and a P-value < 0.00). The observations suggest that banana has the potential to be utilized as trap crops for pineapple mealybug, and can be considered in IPM strategy to control pineapple mealybug.

Feeding Preferences of the Bean Leaf Beetle (Ootheca spp.) (Coleoptera: Chrysomelidae): Insights for Targeted Pest Control Strategies in Uganda.

The bean leaf beetle (BLB) (Ootheca spp.) is a polyphagous pest causing significant yield losses in Uganda, particularly in the Northern and Eastern regions on various hosts plants. Despite its polyphagous behaviour, the BLB exhibits preferential feeding, offering an opportunity for targeted pest management. This study explored its feeding preferences across seven crops: common bean, cowpea, greengram, okra, roselle (malakwang), groundnuts, and soybean. This study was conducted in Arua and Lira districts using a randomized complete block design for two rainy seasons (2018A and 2018B). The results showed significant differences in BLB abundance and foliar damage among host crops, locations, days after planting and seasons. Cowpea was the most preferred crop while groundnuts was the least preferred. Therefore, cowpea can be recommended for use as a trap for managing Ootheca spp. in gardens where it is not the main crop. There was a higher pest abundance in Arua than in Lira. There was also a higher pest abundance in 2018A than in 2018B. These findings highlight the importance of understanding BLB's feeding preferences for implementing effective IPM strategies, emphasizing the potential role of trap cropping, especially with cowpea, to minimize BLB damage in resource-constrained agricultural settings.

Resistance and susceptibility of different Barbarea (Brassicaceae) species and types to cabbage whitefly (Hemiptera: Aleyrodidae) and cabbage white butterfly (Lepidoptera: Pieridae)

Several Barbarea spp. (Brassicaceae) have been tested as trap crops for the diamondback moth Plutella xylostella L. (Lepidoptera: Plutellidae). The use of trap crops can be affected by their susceptibility to other pests, especially if the purpose is to reduce insecticide use. Barbarea rupicola Moris, B. verna (Mill.) Asch., and B. vulgaris Aiton (types G and P) (Brassicaceae) were tested for their susceptibility to the cabbage whitefly Aleyrodes proletella L. (Hemiptera: Aleyrodidae). The percentage of plants showing infestation by cabbage whiteflies ranged from 50% in G-type B. vulgaris and 8.3% in B. verna to no infestation at all in B. rupicola and P-type B. vulgaris. On the other hand, 95.8% of P-type plants showed symptoms of powdery mildew, Erysiphe cruciferarum Opiz ex L. Junell (Erysiphales: Erysiphaceae), while the G type and the other Barbarea spp. were unaffected by this pathogen. Additionally, the G and P types were used in two-choice oviposition preference tests to compare their attractiveness to the small white butterfly Pieris rapae L. (Lepidoptera: Pieridae). No significant differences in total oviposition per plant were found between the two types, but within-plant differences show that the small white butterfly prefers to oviposit on the adaxial leaf side in the P type. This study indicates that in locations where the cabbage whitefly is an economic pest, B. verna, which can also be used as a dead-end trap crop for the diamondback moth, could be chosen over G-type B. vulgaris.

Grower assessment of profitability impact from Brown Marmorated Stink Bug, Halyomorpha halys (Stål), the value of management information sources, and use of potential management practices

AbstractAn online survey was conducted from June 2018 to March 2021 to elicit information from commercial farmers and growers on the economic impact of the Brown Marmorated Stink Bug (BMSB) (Halyomorpha halys (Stål)) on agriculture and their attitudes towards adopting various alternative management practices, including use of Trissolcus japonicus as a biocontrol agent. Most respondents reported that BMSB reduced the profitability of their operation, with the largest impacts coming from reduced quality and increased spray cost. Improved monitoring techniques and natural enemies have the greatest probability to be used to manage BMSB, while tactics like attract and kill, border sprays, repellents, trap crops and netting were less likely to be adopted. Further analysis using ordered logistic and tobit regression models shows that the factors that influence potential adoption vary significantly for each management practice. This suggests that adoption efforts for alternate management practices should focus on the attributes of specific commodity groups and targeted educational programmes may be required to overcome the resistance of growers using conventional growing practices. Several variables have a consistent impact on the respondent's willingness to pay for a T. japonicus‐based biocontrol including being a commercial producer (positive impact), use of conventional growing practices (negative) and increased concern about the impact of BMSB (positive).

Host preferences of an invasive specialist herbivore and native predators on chemically defended plants

Abstract Herbivorous insects generally choose host plants that optimize their growth. However, many specialists choose chemically defended host plants that slow their growth, prioritizing protection from natural enemies. Invasive specialist herbivores may have an added advantage in their non‐native range where they lack co‐evolved specialist natural enemies, in addition to being unpalatable to generalist predators. Here, we explore the diet preferences of the invasive yellowmargined leaf beetle, Microtheca ochroloma and those of native natural enemies. We measured M. ochroloma preferences among six Brassica cultivars varying in glucosinolate concentrations. In both field and laboratory experiments, M. ochroloma preferred the relatively less defended host plants, mizuna and Chinese cabbage. M. ochroloma grew quickest on mizuna. Generalist predators also preferred to eat M. ochroloma larvae that had been fed mizuna in choice trials, yet in the field, predatory insects were least commonly found on mizuna, and most commonly found on plants dominated by native herbivores. M. ochroloma consumes plants that increase their susceptibility to predators, but predation pressure in the field appears to be generally low. Our results suggest that invasive specialist herbivores may prioritize growth over protection against natural enemies. Weak top‐down regulation of specialist herbivore invaders might enable them to exploit less‐defended host plants in their novel range that facilitate faster growth and exacerbate crop damage. Invasive pests may be more effectively managed by leveraging plant preferences in the novel host range in trap crop systems.

An Overview of the Biological Aspects, Nature of Damage and Strategies for Managing the Gram Pod Borer (Helicoverpa armigera Hubner) in Chickpea: A review

Gram pod borer, Helicoverpa armigera, a globally widespread and cosmopolitan insect pest, poses a significant threat to chickpea productivity worldwide. The effective management of this pest is paramount for ensuring sustainable chickpea yields. The life cycle of H. armigera spans approximately 4-5 weeks, progressing through egg, larvae, pupae and adult stages. During the initial 1st to 3rd instar larval phases, the insect primarily engages in feeding on leaves, twigs, and flowers. As the larvae advance to the 4th to 6th instar stages, they shift their focus to developing pods, creating holes or bores and consuming entire seeds. Yield losses of up to 90 percent may occur, contingent upon insect density and cultivar susceptibility. A comprehensive approach to sustainable chickpea pod borer management encompasses the utilization of resistant cultivars, strategic manipulation of sowing dates, maintaining optimal crop density, nutritional management, deployment of trap crops (such as maize, sunflower, sorghum, safflower, pigeon pea, okra and tomato), installation of animated bird perches and the application of biological control measures involving plant extracts, virus/bacteria-based insecticides and entomopathogenic nematodes. In instances of pod borer outbreaks, chemical insecticides are considered a last resort for farmers. However, the adoption of resistant cultivars, adherence to recommended cultural practices and the integration of biological control methods have proven to be more efficacious, economically viable, sustainable and environmentally friendly in the management of chickpea pod borer.

Identifying candidate host plants for trap cropping against Drosophila suzukii in vineyards

AbstractThe spotted wing drosophila (SWD), Drosophila suzukii Matsumura (Diptera: Drosophilidae), is a serious pest in vineyards where it is difficult to control. Trap cropping, which involves manipulating the host plant composition in the crop vicinity to lure the pest away from grapes and towards more attractive host plant fruits, might be an interesting but so far neglected control approach to limit SWD egg-laying in grapes. An ideal trap crop should be more attractive to the pest than the actual crop and should ideally restrict pest development. We determined the attractiveness of fruits of 60 plant species for SWD egg-laying and their suitability for larval development in laboratory assays. Compared to grapes, 16 of the 60 fruits were strongly preferred by SWD females for egg-laying and additionally inhibited the development of SWD larvae into adults. Host preference was strongly influenced by the hardness of the fruit skin, and larval development was marginally affected by the acidity of fruits. However, none of the measured fruit traits had a significant effect on the emergence success of SWD. All 16 candidate trap crop plants should be further tested for their potential to reduce SWD infestation of grapes. We provide practical advice on the next steps to be taken for implementing a successful trap cropping strategy against SWD in commercial vineyards.

Using mung bean as a trap crop and biopesticide for control of soybean pest

Many pests attack soybean plants and can cause high-yield losses. To reduce crop damage, using chemicals in the field can potentially cause harmful effects on the environment. Using traps-crops, and biopesticides will be tested as an effective and safe control method. The research was done in the dry season of the tidal land of Tumih Village South of Kalimantan. The design used was RCBD which consisted of six treatments and was repeated four times. The treatment tested were 1). Check, 2). Biopesticides 6 times, 3). Biopesticide 4 times, 4). Biopesticides 6 times + mung bean as trap crop 6%, 5). Biopesticides 4 times + mung bean as trap crop 6%, 6. Insecticides 6 times. The results indicated that armyworms Spodoptera litura and Lamprosema indicata were important pests. Armyworm attacks in the vegetative phase reached 82%. However, the yields obtained were around 2,069 to 2,463 t/ha. Soybean yields in treatment plots with 6% trap crop were 1,664 to 1,969 t/ha. Anjasmoro varietal is not recommended In endemic areas of the armyworm.

Trap crops enhance the control efficacy of Metarhizium brunneum against a soil-dwelling pest

Soil-dwelling insect pests may cause considerable damage to crops worldwide, and their belowground lifestyle makes them hard to control. Amongst the most promising control agents for subterranean pests are soilborne entomopathogenic fungi (EPF) such as Metarhizium brunneum. Albeit EPF can be highly pathogenic to their target pest species under laboratory conditions, their efficacy in the field is often limited due to adverse environmental conditions. Here, we test for the first time if the efficacy of EPF can be improved when they are augmented with trap crops. In a field experiment, the M. brunneum strain ART2825 was combined with a trap crops mixture of six plant species and evaluated for its control effect of wireworms (Coleoptera: Elateridae). When both were combined in the main crop, potato damage was lowered on average by 42.5% and wireworm abundance by 50.8%. Single application of trap crops or EPF lowered damage/pest abundance only by 29.9%/15.89% and 34.7%/4.77%, respectively. Importantly, the strength of the synergistic pest control effect between trap crops and EPF increased disproportionately with increasing wireworm abundance. However, DNA-based gut content analysis showed that wireworms’ feeding preferences were not shifting toward the trap crops. Our findings demonstrate that combining trap crops with EPF improves the efficacy of the latter and leads to a synergistic control effect which magnifies with increasing wireworm abundance. Hence, the synergistic effect of EPF and trap crops might be a promising control strategy for soil-dwelling pests in general and significantly improve our abilities to manage soil pests environmentally friendly.