Scirpophaga Incertulas Research Articles

Marker-free transgenic Bt rice engineered for resistance to yellow stem borer and leaffolder

Marker-free transgenic Bt rice engineered for resistance to yellow stem borer and leaffolder

Revealing pest patterns: A comparative spatial distribution analysis of insect threats in Kharif rice across the key agricultural regions in the Eastern India.

This study investigates the spatial distribution and aggregation patterns of major insect pests in Kharif rice fields during the 2023 growing season in Eastern India. The analysis focuses on key pests such as yellow stem borer (YSB), gall midge, green leaf hopper (GLH), and brown planthopper (BPH), as well as rice thrips, caseworm, whorl maggot, Gundhi bug, grasshopper, and leaf folder. Using statistical indices, this study aims to understand pest behavior across Standard Meteorological Weeks (SMWs) to better inform pest control strategies. The study reveals significant clustering and aggregation patterns among the pests. YSB exhibited variance-mean ratio (VMR) values between 1.14 (40th SMW) and 1.96 (31st SMW), with dispersion parameter (K) values ranging from 0.57 to 21.65, and a peak index of dispersion of 132.66 (43rd SMW). Similarly, gall midge showed VMR values from 6.19 to 10.48, whereas GLH and BPH recorded VMR ranges of 1.19 to 132.10 and 1.01 to 1.50, respectively. These spatial distribution trends were confirmed through values for Iwao's patchiness index and Taylor's power law, indicating strong pest aggregation in specific areas. The results underscore the need for region-specific integrated pest management strategies that take into account pest clustering and environmental factors influencing pest distribution. Although an S-curve pattern of infestation-showing gradual population increases, rapid peaks, and eventual decline-was observed, the primary focus remains spatial patterns, which are critical for optimizing pest management and improving rice crop sustainability in the region. © 2024 Society of Chemical Industry.

Prealighting and Postalighting Volatile Organic Compounds Emitted by Rice Influence the Behavior of Scirpophaga incertulas.

Yellow stem borer (YSB), Scirpophaga incertulas, is a major rice pest causing significant yield losses worldwide. We investigated how volatile organic compounds (VOCs) released by the rice variety TN1, both before and after infestation, as well as by its companion weeds, Echinochloa colona and Echinochloa crus-galli, influence the behavior of YSB in host selection, recognition, and establishment. Olfactometry bioassays showed that uninfested TN1 plant VOCs attracted YSB more than those from YSB-infested rice plants and weeds. Changes in the VOC profile of TN1 during 24-48 h post-YSB infestation revealed that these postalighting compounds may deter YSB oviposition. Xylene, cymene, 1,2,3,4-tetrahydro naphthalene, dodecanol, and tetradecanol could be possible YSB attractants based on metabolomics, olfactometry, and GC-EAD studies. This work illuminates rice plant-YSB chemical interactions and VOCs dynamic function in attraction and defense processes. These findings provide a foundation for developing VOC-based pest management strategies to mitigate yield losses in rice farming.

Efficacy of Insecticides Against Yellow Stem Borer (Scirpophaga incertulas Walker) and Rice Leaf Folder (Cnaphaocrocis medinalis Guenee) and Their Impact on Natural Enemies in Rice Ecosystem

The experiment was conducted at AAU-Assam Rice Research Institute, Titabor to test the efficacy of some insecticides against yellow stem borer and rice leaf folder. Out of 8 tested insecticides, Chlorantraniliprole 18.5 SC showed the best result in minimizing yellow stem borer and rice leaf folder infestation. The lowest infestation percentage of yellow stem borer (2.10%) was observed on Chlorantraniliprole 18.5 SC treated plots followed by treatment with Chlorantraniliprole 10% + Lambda Cyhalothrin 5% ZC (2.33 %) at 7 DAT. Similarly, white ear head (0.33%) was also recorded as the lowest on Chlorantraniliprole 18.5 SC treated plots. Chlorantraniliprole 18.5 SC recorded the lowest infestation percentage of rice leaf folder at 7 DAT (3.40 %) and 14 DAT (3.53 %) followed by Chlorantraniliprole 10% + Lambda Cyhalothrin 5% ZC. While, the highest number of spiders and coccinellids were recorded in Chlorantraniliprole 0.4GR (2.43 spider/plant and 1.33 coccinellids/plant) followed by Thiamethoxam 25WG (2.13 spiders/plant and 1.10 coccinellids/plant). In terms of yield, Chlorantraniliprole 18.5 SC was found to be the best insecticide which provided the highest yield of 5.83t/ha among all the tested insecticides.

A generalizable and interpretable model for early warning of pest-induced crop diseases using environmental data

Pest infestations and resulting crop diseases threaten global food security. Traditional pest and disease monitoring methods are time-consuming and prone to delays, thus necessitating the development of effective prediction strategies that facilitate early and timely detection. In response to this challenge, this research proposes a generalizable and interpretable machine learning model to predict two major rice pests—Green Leafhopper and Yellow Stem Borer—and a No Pest class using environmental data collected from various regions in India. The dataset, comprising factors such as temperature, humidity, and rainfall, underwent rigorous preprocessing. Key features like temperature difference, humidity difference, and vapor pressure deficit were engineered to enhance the model’s performance. Twelve baseline models were trained and their performance was evaluated using F1 scores and AUC values due to the imbalanced nature of the dataset. Through statistical analysis of baseline models, Random Forest, Balanced Random Forest, XGBoost, and CatBoost models, were selected for hyperparameter tuning via Optuna. The tuned CatBoost model demonstrated superior performance, achieving AUC values of 0.99 for Green Leafhoppers, 0.98 for Yellow Stem Borers, 1.00 for No Pest class and an overall F1 score of 0.9414 with a mean AUC value of 0.9912 across all classes. Additionally, Explainable Artificial Intelligence techniques, particularly SHAP, were employed to interpret the model’s predictions, identifying the relative importance of environmental factors in pest occurrence. This interpretability aligns the model’s predictions with established agronomic knowledge, enhancing its practical utility for early pest and disease detection. The generalizability of the proposed model suggests it can be adapted to other crops and regions, offering a valuable tool for early warning systems in agriculture, promoting sustainable practices, and reducing crop losses due to pests and diseases.

Studies on the tolerance mechanism in selected rice accession against yellow stem borer, Scirpophaga incertulas (Walker)

Studies on the tolerance mechanism in selected rice accession against yellow stem borer, Scirpophaga incertulas (Walker)

Screening of rice cultivars against Scirpophaga incertulas Walker : utilising cluster analysis as a tool to identify resistant cultivars

The field experiment was conducted in the Boro season from December 2022 to April 2023 at the Institutional research farm, Institute of Agriculture, Palli Siksha Bhavana, Visva-Bharati, Sriniketan, Birbhum, West Bengal, for the screening of thirty-three rice cultivars for their resistance to yellow stem borer, Scirpophaga incertulas Walker. The experiment utilized modified percent damage values to grade these cultivars during both vegetative and reproductive stages. Early-duration cultivars displayed varied reactions, with Jaldi 13 (2) exhibiting consistent resistance (2.53% DH, 12.65% D), while others showed moderate resistance or susceptibility with deadheart percentages ranging from 4.73% to 8.51% and corresponding damage percentages between 23.65% and 42.55%. This trend extended to reproductive stages, where all early-duration cultivars demonstrated moderate to high susceptibility, with damage percentages between 30.8% and 54.5%. The mid-early duration cultivars displayed mixed responses, with Sahabhagi (4) demonstrating moderate resistance (4.92% DH) and Sukumar (3) exhibiting moderate susceptibility (8.21% DH) during the vegetative stage. These diverse reactions continued into the reproductive stage, providing a comprehensive understanding of their responses to the pest. Additionally, in medium and late-duration cultivars, a range of reactions persisted, with cultivars like Pratiksha (20) showing moderate resistance (6.63% DH) in the mid-duration category and Ajith (25) displaying moderate resistance (6.33% DH) in the late-duration category. Cluster analysis categorized the cultivars into distinct groups, showcasing a mix of resistant, moderately resistant, and susceptible types across all growth durations. Notably, cultivars like Gotra 1 (10), Parijat (14), Pushpa (17), PNR 546 (19), Pravat (23) and Gotra 2 (31) consistently demonstrated resistance or moderate resistance across different growth stages, suggesting their potential suitability in tailoring resistant breeding programs and pest management strategies against the stem borer in rice cultivation.

Seasonal variations of insect abundance: Correlating growth stage-specific metrics with weather patterns in Rangpur Region, Bangladesh

The disclosure of insect occurrences correlating with meteorological data is pivotal in devising effective management strategies for rice fields. The study collected data on harmful and beneficial insects, along with meteorological variables, for three consecutive rice-growing seasons in 2021 and 2022. Month-wise insect distribution were delineated, with prominent species such as green leafhopper, brown planthopper, white-backed planthopper, rice whorl maggot, damselfly, parasitic wasps and green mirid bug observed consistently. Notably, most of the harmful insects were predominantly present during March–July and September–October. The spatial distribution, further segmented based on the rice-growing seasons, revealing the Aus season's preeminence in hosting harmful insects followed by Aman and Boro. The prevalence of most of the harmful insects were in tillering stage. Beneficial insects, displayed their dominance during specific months, growth stage, emphasizing their potential role in controlling harmful species and their prevalence were increased by increased of harmful insects. Furthermore, the study elucidated the correlation between climatic factors and insect abundance, emphasizing the role of temperature, rainfall and relative humidity. Temperature metrics and relative humidity manifested significant associations with several insects both harmful and beneficial species differently. While rainfall notably correlated with rice bug, short-horned grasshoppers, yellow stem borer, and non-significant association with other insects. The study underscored mutual dependencies between predator and prey species, emphasizing the ecological balance within the agricultural ecosystem. This comprehensive analysis indicated the need for integrated pest management strategies, considering both harmful and beneficial insect dynamics, to promote sustainable practices for optimizing rice production in changing climatic scenarios.

Zinc Induced Resistant against Yellow Stem Borer (Scirpophaga incertulas, Walker) in Rice

Zinc Induced Resistant against Yellow Stem Borer (Scirpophaga incertulas, Walker) in Rice

Composition of Parasitoid Wasps in Insect Pests of Rice (Rice Leaffolder, Cnaphalocrocis Medinalis Guenée)

Biological control is one aspect of Integrated Pest Management (IPM). The method focusses on natural enemies; beneficial insects are applied for biological control of agricultural insect pests and also provide an environmentally friendly approach. For the rice pests including Rice Leaf Folder (RLF), several parasitoids tend to be natural enemies that could be used to control the pest from the egg stage to pupa. This study was conducted with two varieties of rice, namely “Sen Kra Oub” and “Sro Ngea” at Battambang Province of Cambodia. Parasitoid wasps were collected from egg to pupa stages of RLF and rice yellow stem borer by rearing method, and stored in 70% of alcohol solution before sending for identification in Vietnam’s Institute of Ecology and Biological Resources (IEBR) Laboratory. The outcomes revealed that five hymenopteran parasitic wasps of three different families were found, viz. Apanteles cypris Nixon, Bracon onukii Watanabe and Pentatermus striatus (Szepligeti) (Braconidae), Xanthopimla flavolineata Cameron (Ichneumonidae), and Telenomus rowani Gahan (Scelionidae) and being the primary parasitoids of rice leaffolder, Cnaphalocrocis medinalis Guenee; stemborer Scirpophaga incertulas Walker (Pyralidae) and black branded swift Pelopidas mathias (Hesperiidae). Parasitism was not found at the vegetative phase with Sen Kra Ob varieties but in reproductive phase. parasitism proportion was 16.66% and 28.57% to 50% in ripening phase, different from Sro Ngea variety where a proportion was found in vegetative phase 27.27%, reproductive phase at 28.57% to 40% and 28.57% to 43% in ripening phase. All the hymenopteran parasitoids were initially recorded in Cambodia, whereby all the parasitoids were potential agents for biological control for important rice insect pests. The outcome of this research suggests that the Government should invest more in the research and development for biological control in Cambodia.

Origins of Susceptibility to Insect Herbivores in High-Yielding Hybrid and Inbred Rice Genotypes.

Several studies have reported higher damage from insect herbivores to hybrid compared to inbred (pure line) rice. We used a collection of 20 hybrid and 12 inbred genotypes from diverse origins to test the hypotheses that hybrid rice susceptibility is due to (a) the hybrid plant type and/or (b) rice phylogeny. We challenged the genotypes with Nilaparvata lugans (BPH), Sogatella furcifera (WBPH) and Scirpophaga incertulas (YSB) in greenhouse and screenhouse bioassays and monitored herbivores in field plots. We used single nucleotide polymorphic (SNP) markers to assess genetic similarities between the genotypes and found that the hybrids and inbreds formed two distinct clusters regardless of origin. In the screenhouse, hybrids were more susceptible than inbreds to YSB; however, resistant hybrids and susceptible inbreds were also apparent from both the screenhouse and field plots. Plant biomass was the best predictor of susceptibility to YSB. Plant origin had a greater effect than plant type on susceptibility to BPH and WBPH. WBPH was the most abundant planthopper in the field plots where numbers were highly correlated with planthopper fitness in the greenhouse bioassays. Our results provide evidence that high-yielding hybrids that are relatively resistant to herbivores can be achieved through careful breeding. The avoidance of susceptible genotypes during breeding should remain a key element of integrated rice pest management.

Volatolomics to Decrypt the Monophagous Nature of a Rice Pest, Scirpophaga Incertulas (Walker).

Scirpophaga incertulas Walker (Lepidoptera: Crambidae, yellow stem borer, YSB) is a monophagous insect pest that causes significant yield loss in rice (Oryza staiva L.). Semiochemical based pest management is being sought as an alternate to chemical pesticides to reduce pesticide footprints. We hypothesized differential release of volatiles from host rice and two companion non-host weeds, Echinochloa colona and Echinochloa crus-galli could be responsible for oviposition and biology of YSB and these chemicals could be used for YSB management. Number of eggs laid, and number of larvae hatched were significantly higher in rice plant as compared to weeds. YSB could only form dead hearts in rice plants. YSB significantly preferred host-plant volatiles compared to the non-host plants both in choice and no-choice tests in an Y-tube olfactometer. 2-Hexenal, hexanal, 2,4-hexadienal, benzaldehyde, nonanal, methyl salicylate and decanal were found in the leaf volatolomes of both the host and non-host plants in HS-SPME-GC-MS (Headspace-Solid phase micro extraction-Gas chromatography-Mass spectrometer). Pentene-3-one, 2-pentyl furan, 2,4-heptadienal, 2-octenal, 2-octenol and menthol were present only in the non-host plants. Fourteen rice unique compounds were also detected. The built-in PCA (Principal Component Analysis) and PLS-DA (Partial least squares-discriminant analysis) analysis in the MS-DIAL tool showed that the volatiles emitted from TN1 formed a cluster distinct from Echinochloa spp. and 2-octenal was identified as a unique compound. Olfactometer bioassays using synthetic compounds showed that rice unique compounds, like xylene, hexanal served as attractants whereas non-host unique compounds, like 2-pentylfuran, 2-octenal acted as repellent. The results indicate that the rice unique compounds xylene, hexanal along with other volatile compounds could be responsible for higher preference of YSB towards rice plants. Similarly, the non-host unique compounds 2-pentylfuran, 2-octenal could possibly be responsible for lower preference and defence against YSB. These compounds could be utilised for devising traps for YSB monitoring and management.

Bio-efficacy of certain newer insecticides and fungicides both alone and in combination against yellow stem borer and sheath blight in rice

Bio-efficacy of certain newer insecticides and fungicides both alone and in combination against yellow stem borer and sheath blight in rice

Predictive modelling of yellow stem borer population in rice using light trap: A comparative study of MLP and LSTM networks

AbstractThe yellow stem borer (YSB), Scirpophaga incertulas (Walker), is a major insect pest that significantly damages rice crop. This study investigates methods to predict YSB populations in rice fields, aiming to develop an early warning system. Traditionally, rice farmers rely on light traps to monitor YSB presence. However, this study goes beyond this approach by combining light‐trap data with weather information (temperature, humidity, rainfall) and utilizing powerful artificial intelligence (AI) techniques to forecast future YSB populations. Two AI methods, multilayer perceptron (MLP) and long short‐term memory (LSTM), were employed to estimate YSB populations and assess their performance. The results revealed that the LSTM model outperformed the MLP model based on statistical metrics like RMSE, MAE, and R2 values. Utilizing LSTM model with historical data, stakeholders in the Eastern Coastal Plains and Hills agro‐climatic zone of India can gain a significant advantage in predicting YSB populations well in advance. This early warning system can alert stakeholders of potential YSB outbreaks, allowing them to take timely management actions and protect their rice crops from substantial yield losses.

Efficacy of different pesticides in suppressing yellow stem borer in spring rice (Oryza sativa) in Ratuwamai, Morang, Nepal

Rice, a staple food for over half the global population, is crucial for food security, economic stability, and cultural significance. Its production, however, is threatened by pests like the Yellow Stem Borer (YSB), which causes substantial yield losses, especially in rice-dominant regions like Nepal. This study focuses on evaluating the effectiveness of biological, botanical, and chemical pesticides against YSB in spring rice crops of Ratuwamai, Morang, Nepal. For this, we apply biological methods/pathogens like Bacillus thuringiensis, to target YSB; botanical pesticides, derived from plants like Azadirachtin and Mugworth, act as repellents; while chemical pesticides such as Cypermethrin, Chlorpyriphos and Cartap Hydrochloride offer rapid control but come with environmental risks. Among those six pesticides used, the present findings revealed that chlorpyriphos 20% EC have minimum mean dead heart with 4.92% and cypermethrin 10% EC have minimum mean white ear head with 2.44% respectively after application of first and second dose of treatments respectively. Likewise, most plant yield attributes were superior where chlorpyriphos was used. Though bacillus and azadirachtin reduced the dead heart and white ear head symptoms, they couldn’t give good yield than that of chemical pesticides. Thence, through our research we investigated the impacts of different biological, botanical and chemical pesticides in controlling YSB population densities, and influencing yield and yield attributing characters from the field experiment.

Effect of Chemicals and Biopesticides against Yellow Stem Borer [Scirpophaga incertulas (Walker)] at Prayagraj

The experiment was conducted at the research field of Department of Entomology, Sam Higginbottom University of Agriculture Technology and Sciences Prayagraj, during Kharif season 2023. The experiment was laid out in a Randomized Block Design (RBD) with three replications, Eight treatments were evaluated against yellow stem borer Scirpophaga incertulas viz., Spinosad 45SC @ 0.2ml/l, Beauveria bassiana (1x108CFU/g) @1.5 g/l, Fipronil 5SC @ 2ml/l, Acephate95SG @ 682ga.i/ha, Metarhiziumanisopliae (1.15% CFU) @2000g/ha, Lamda Cyhalothrin 5EC@ 0.5ml/l, Bacillus thuringiensis (2x109 POB) @1.5g/l, and Control. Among the different chemical and biopesticides, the pooled analysis of per cent dead hearts were recorded least in Spinosad45SC which was the most effective treatment with (12.98% and 13.93%) mean dead heart percent , followed by Lamda Cyhalothrin 5EC (13.27% and 14.63%), Acephate95SG (13.58% and 15.06%) and Fipronil 5SC (14.10% and 15.29%).The next best treatments were found to be Beauveria bassiana (1x108CFU/g) (14.38% and 15.67%), Bacillus thuringiensis (2x109 POB) (14.64 and 15.94%), Metarhizium anisopliae (1.15%CFU) (14.97 and 16.19%) and the highest dead heart percent infestation of Scirpophaga incertulas (Walker) was found in Control (15.77% and 18.54%). The highest yield and cost benefit ratio was recorded from Spinosad (51.5q/hac) and (1:4.51), followed by Lamda Cyhlothrin (45q/hac) and (1:4.35), Acephate (43q/ha c) and (1:4.18).

Heterosis for Interactions between Insect Herbivores and 3-Line Hybrid Rice under Low and High Soil Nitrogen Conditions.

Hybrid rice results from crossing a male-sterile line (the A line) with a pollen doner (the restorer or R line). In 3-line hybrid breeding systems, a fertile B line is also required to maintain A line populations. Heterosis is defined as a condition of traits whereby the hybrid exceeds the average of the parental lines. Heterobeltiosis is where the hybrid exceeds both parents. Hybrid rice may display heterosis/heterobeltiosis for growth, yield and resistance to herbivores, among other traits. In a greenhouse experiment, we assessed the frequency of heterosis for resistance to the brown planthopper (Nilaparvata lugans (BPH)), whitebacked planthopper (Sogatella furcifera (WBPH)) and yellow stemborer (Scirpophaga incertulas (YSB)) in eight hybrids under varying soil nitrogen conditions. We also assessed plant biomass losses due to herbivore feeding as an approximation of tolerance (the plant's capacity to compensate for damage). Nitrogen reduced resistance to all three herbivores but was also associated with tolerance to WBPH and YSB based on improved plant survival, growth and/or yields. Plant biomass losses per unit weight of WBPH also declined under high nitrogen conditions for a number of hybrids, and there were several cases of overcompensation in rice for attacks by this herbivore. There was one case of nitrogen-related tolerance to BPH (increased grain yield) for a hybrid line with relatively high resistance, likely due to quantitative traits. Heterosis and heterobeltiosis were not essential to produce relatively high herbivore resistance or tolerance across hybrids.

SURVEY OF LEPIDOPTERAN PESTS OF RICE ORYZA SATIVA L. FROM NAGALAND

A field survey was carried out in the farmer?s field located at Chutsolie colony, Chumukedima, Nagaland, from July to November 2022 using light traps to study the incidence of lepidopteran pests occurring in rice, Oryza sativa L. The survey was conducted from the vegetative till harvesting stages of paddy. Fortnightly, observations of the lepidopteran pests were done and correlated with the weather parameters. During the survey, four lepidopteran pests, namely, Cnaphalocrocis medinalis (Guenee), Leucania loreyi (Duponchel), Melanitis leda (Linnaeus), and Scirpophaga incertulas (Walker) were observed. The highest peak population of C. medinalis (Guenee), M. leda (Linnaeus), and S. incertulas (Walker) were observed on the 37th standard mean week (SMW) (i.e., vegetative stage) whereas the highest population of L. loreyi on 41st SMW. (i.e., reproductive stage). The species M. leda constituted the highest population (75) and persisted in the field till the harvest, followed by S. incertulas (51), and C. medinalis (47). The species L. loreyi was the least in numbers (16). Among the species recorded, L. loreyi was the new record from Nagaland.. KEYWORDS :Cnaphalocrocis medinalis, Incidence, Leucania loreyi, Melanitis leda, Pests, Rice, Scirpophaga incertulas

Non-target Organisms Captured in the Sex Pheromone Traps of Yellow Stem Borer of Rice

Non-target Organisms Captured in the Sex Pheromone Traps of Yellow Stem Borer of Rice

Periodic colonization of Trichogramma japonicum for bio-control of yellow stem borer (Scirpophaga incertulas) in summer low-land rice (Oryza sativa)

Yellow stem borer [Scirpophaga incertulas (Walker)], is a major pest of low-land rice (Oryza sativa L.), causing 30–40% yield losses. The use of biological control agents to suppress yellow stem borer (YSB) population and damage across Asia includes inundative releases of the egg parasitoid, Trichogramma japonicum Ashmead. However, information on the time and number of parasitoids’ releases are lacking to control YSB in summer low-land rice. Therefore, an experiment was conducted during summer seasons of 2018 and 2019 at ICAR-National Institute of Biotic Stress Management, Raipur, Chhattisgarh to standardize the time and number of T. japonicum releases for effective biocontrol of YSB. Experiment consisted of 3 different treatment schedules, viz. T1, Four releases of T. japonicum at weekly intervals on the 7th, 14th, 21st, 28th days after planting (DAT); T2, Four releases of T. japonicum at weekly intervals on the 14th, 21st, 28th, 35th DAT; T3, Four releases of T. japonicum at weekly intervals on the 21st, 28th, 35th, 42nd DAT; and T4, Control (no release of wasps). Significant reduction of YSB-induced damage symptoms was observed in the treatment schedule (T2) consisting of four releases of T. japonicum (@50,000 wasps/ha/release) at weekly intervals on the 14th, 21st, 28th, 35th DAT of rice which significantly reduced the dead heart (9.1%, 45.83% reduction over control) and the white ear (1.8%, 47.05% reduction over control), as compared to untreated control plots (T4) (16.8% dead heart, 3.4% white ear) in summer 2018. Similarly, in summer 2019, the reduction in dead heart and white ear by the treatment (T2) was 43.35% and 46.15% over control, respectively. The significant reduction of YSB-induced damages corresponded with the increased grain yield in (T2) from 2018–19 i.e. 12.74–20.18% across the seasons. The results suggest that the (T2) augmentative releases provided ecologically viable bio-control of YSB during the summer seasons in low-land rice.