Green Leafhopper Research Articles

Investigation on the Abiotic Influences on Amplitude Fluctuation in the Incidence of Major Pest of Rice in Eastern Uttar Pradesh, India

An experiment was conducted at Students Instructional Farm, Acharya Narendra deva University of agriculture and technology Kumarganj, Ayodhya (U.P.). during Kharif season 2021. The incidence that, the yellow stem borer, leaf folder, green leaf hopper, BPH and gundhi bug were recorded. The highest dead heart per cent of yellow stem borer was recorded on rice at 36th SMW (12.97 per hill) and white ear per cent (7.41 per hill) in 44th SMW, leaf folder 41st and 32nd SMW (6.75 & 0.10 per hill), green leaf hopper 43th and 32nd SMW (3.25 & 0.20 nos./hill), BPH 44th and 34th SMW (9.84 & 0.15 nos./hill) and gundhi bug 45th and 40th SMW (1.37 & 0.20 per hill).
 Yellow stem borer (dead heart) was showed non-significant positive correlation with rainfall, minimum, maximum temperature and sun shine however, relative humidity showed significant positive correlation with dead heart. White ear showed that non-significant negative correlation with rainfall while, minimum, maximum temperature and relative humidity significant negative correlation however, sun shine showed non- significantly positive correlation with white ear. Leaf folder incidence showed non- significant positive correlation with rainfall and relative humidity, maximum and minimum temperature showed non-significant negative correlation, however sun shine showed significant positive correlation. Relative humidity and rainfall exhibited non-significant negative correlations with the incidence of green leaf hopper, although substantial positive correlations with sun shine and minimum and maximum temperatures were observed. Minimum and maximum temperatures, relative humidity, and rainfall all exhibited non-significant negative correlations with the population of BPH; however, sunshiny days revealed a substantial positive link. The incidence of gundhi bug, showed significant negative correlation with minimum, maximum temperature and relative humidity correlation while rainfall and sun shine showed non-significant negative correlation and non-significant positive correlation respectively.

Combined Transcriptome and Proteome Analysis of the Protein Composition of the Brochosomes of the Leafhopper Nephotettix cincticeps.

Brochosomes, unique coatings on the integuments of Cicadellidae, are synthesized in specialized glandular sections of Malpighian tubules. However, limited knowledge exists regarding the protein composition of brochosomes. In this study, we conducted transcriptomic and proteomic profiling to characterize the brochosome protein composition in the rice green leafhopper Nephotettix cincticeps. Brochosomes were collected from the forewings of leafhoppers using ultrasonic treatment, allowing for more effective brochosome collection and shaking treatment, resulting in purer brochosomes. Transcriptome sequencing analysis identified 106 genes specifically expressed in the Malpighian tubules; combined with proteomic data, we identified 22 candidate brochosome proteins. These proteins were classified into 12 brochosomins (BSM) and 10 brochosome-associated proteins (BSAP) based on previous research. Conserved motif analysis and functional predictions unveiled unique motifs in each BSM, while BSAP appeared to play a crucial role in BSM folding and pathogen resistance. Comparative analysis of other Hemiptera species demonstrated that all BSM and some BSAP are specific to the Cicadellidae family. Our findings could contribute to understanding the mechanism of brochosome synthesis, its function, and evolutionary genesis.

Fumigant activity and transcriptomic analysis of two plant essential oils against the tea green leafhopper, Empoasca onukii Matsuda.

Introduction: The tea green leafhopper, Empoasca (Matsumurasca) onukii Matsuda, R., 1952 (Hemiptera: Cicadellidae), is currently one of the most devastating pests in the Chinese tea industry. The long-term use of chemical pesticides has a negative impact on human health, impeding the healthy and sustainable development of the tea industry in this region. Therefore, there is a need for non-chemical insecticides to control E. onukii in tea plants. The essential oils from plants have been identified for their potential insecticidal ability; however, there is a lack of knowledge regarding the effect of plant essential oils on E. onukii and its gene expression. Methods: In order to address these knowledge gaps, the components of Pogostemon cablin and Cinnamomum camphora essential oils were analyzed in the present study using gas chromatography-mass spectrometry. The fumigation toxicity of two essential oils on E. onukii was tested using sealed conical flasks. In addition, We performed comparative transcriptome analyses of E. onukii treated with or without P. cablin essential oil. Results: The 36-h lethal concentration (LC50) values for E. onukii treated with P. cablin and C. camphora essential oils were 0.474 and 1.204μLmL-1 respectively. Both essential oils exhibited the potential to control E. onukii, but the fumigation activity of P. cablin essential oil was more effective. A total of 2,309 differentially expressed genes were obtained by transcriptome sequencing of E. onukii treated with P. cablin essential oil. Conclusion: Many of differentially expressed genes were found to contain detoxifification genes, indicating that these families may have played an important role when E. onukii was exposed to essential oil stress. We also found differential expression of genes related to redox-related gene families, suggesting the upregulation of genes associated with possible development of drug and stress resistance. This work offers new insights for the prevention and management of E. onukii in the future.

Complete genomes of mutualistic bacterial co-symbionts "Candidatus Sulcia muelleri" and "Candidatus Nasuia deltocephalinicola" of the rice green leafhopper Nephotettix cincticeps.

The genomes of obligate bacterial co-symbionts of the green rice leafhopper Nephotettix cincticeps, which is notorious as an agricultural pest, were determined. The streamlined genomes of "Candidatus Sulcia muelleri" and "Candidatus Nasuia deltocephalinicola" exhibited complementary metabolic pathways for synthesizing essential nutrients that contribute to host adaptation.

Sosialisasi Hama Wereng pada Tanaman Padi di Desa Gedangkulut Kecamatan Cerme

Rice is one of the important food crops for the people of Indonesia to meet the need for carbohydrates. This food ingredient contains 73 g of carbohydrates and 8 g of protein in every 100 g of material. As a major food crop, continuity of production is urgently needed so that the quality and quantity remains available. The obstacle often faced by farmers in efforts to increase rice production is the presence of plant-disturbing organisms (OPT). One type of plant-disturbing organism that attacks rice plants is the Wereng Pest, causing losses in quality and quantity. Brown planthoppers and green leafhoppers are groups of pests that can cause rice plants to die or reduce production to the detriment of farmers. The purpose of this research is to conduct outreach to farmers regarding the dangers and what can be done so as not to be exposed to Wereng Pests. This activity was held on June 19 2023 in Gedangkulut Village, Cerme District, Gresik Regency.

Consequences of Weather Parameters and their Correlation with the Sucking Pests and Gundhi Bug of Rice (Oryza sativa L.)

The field experiments were carried out during kharif 2020 and 2021 at the Agriculture Research Station research farm, Sakoli, Dist. Bhandara (Maharashtra) under Dr. Panjabrao Deshmukh Krishi Vidyapeeth, Akola. The findings of this study showed a considerable impact of climatic variables on the biology of sucking pests, notably the rice gundhi bug, brown plant hopper, white-backed plant hopper and green leaf hopper. In kharif 2020, the maximum population of green leaf hopper, brown plant hopper and white backed plant hopper was observed at 45th meteorological weak (2.53 nos/hill), 43rd MW (1.33 nos/hill) and 46th (3.53 nos/hill), respectively. In kharif 2021, the green leaf hopper reached its peak level during at 41st meteorological week (1.67 nos/hill), and the brown plant hopper attained its peak at the 44th meteorological week (9.60 nos/hill), while the maximum population of white backed plant hopper was observed at 43rd meteorological weak (1.33 nos./hill). In contrast, the incidence of the gundhi bug was the highest at 45th (0.27 nos./hill) and 41st meteorological week (0.23 nos./hill) in kharif 2021 and 2022, respectively. Additionally, there was a strong relationship between the investigated pest population and other environmental variables, including maximum temperature, minimum temperature, relative morning humidity, relative evening humidity, rainfall and the number of days with rain during both seasons.

Evaluate the population development of green leafhopper as a tungro vector in the endemic area from long-term data

The epidemiological aspect including monitoring is a critical component of implementing an early warning system. The tungro epidemic in rice is influenced by the population dynamics of the green leafhopper vector. Likewise, rainfall and biotic factors affect the abundance of green leafhopper vectors. Long-term data are essential to explain that mechanism, so population predictions on a seasonal scale can be obtained accurately. This paper analyses weekly data on catching green leafhoppers and other arthropods in a continuous cropping system from 2013-2019. We utilize the climatic data gathered to assess the impact of climatic conditions on population dynamics. To improve the additive and homoscedasticity of the time series, we transform the data. The data are fitted in a linear model. The results showed that the green leafhopper population affected the incidence of tungro in the field. From January to December, the population dynamics of the green leafhopper can be characterized. It can assist in monthly population forecasting for the following years. Exogenous and endogenous variables, however, still need to be studied more comprehensively to identify any other predictive components that should be incorporated.

Diversity and Population Dynamics of Pest in Sambawa Tea Plantation, West Java

Tea plants are grown in monoculture on a large scale, so that can be a caused pest in the high population. This study aims to determine the diversity and dynamics of pest populations in Sambawa tea plantations in West Java. Tea pests are found in the crop and on the leaves picked at the plant. The dynamics of the pest population were noted by observing the area of attack, the intensity of the attack, and population density. Twenty-one pests on tea plants were identified based on their morphological characteristics and symptoms. Among them, seven species attack bud and young leaf, two species attack old leaf, twelve species attack young and old leaves, and one pest attacks tree trunk. Twelve pests were carried to the factory’s withering tub of leaves. Tea green leafhopper (Empoasca sp.), tea leaf roller (Caloptilia theivora), tea mosquito bug (Helopeltis bradyi), and tea tortrix (Adoxophyes sp. and Homona coffearia) were the main pests at the observation site. The population of tea green leafhoppers decreased after the second application of pesticides, post-picking, and heavy rains. The tea leaf roller was not found after the first and second pesticide applications. The population of tea leaf rollers began to increase during picking until the last observation. The highest population of tea mosquito bugs was found after the second pesticide application. The population of tea tortrix decreased after the second pesticide application.

Period of effective catching of insect pests and natural enemies in light traps

Light trap helps to protect natural enemies and manage destructive insect pests in rice farming ecosystem. Light trapping time at night is not identified, for organic farming in farmers level its essential to identified proper timing at night. The experimental light trap was set up at Sagordi rice farm, Bangladesh Rice Research Institute, Barishal, during T. Aman rice season in 2019-2020. The time of catching insects by light trap were divided in six different times in a night and defined as treatments (T1= 17.20 to 18.20, T2= 18.20 to 19.20, T3= 19.20 to 20.20, T4 =20.20 to 21.20, T5=21.20 to 22.20, T6= 22.20 to rest of night insects caught at light trap) in this study. Each treatment has had four replications. Yellow sticky trap used to catch and trapped insect and natural enemyRice insect pests and their natural enemies were counted and recorded manually. The caught of yellow stem borer increased and green leafhopper were decreased from treatment, T1 to treatment, T6. During dusk to first four hours, the percentage of caught was approximately 69.28% insect pests. Overall, the percentages of insect pests trapping were 89.65% and natural enemies were 10.35% during the experimental period. The ratio of destructive insect pests caught was highest compared to that of natural enemies in light trap of rice ecosystem.

Tea green leafhopper-induced synomone attracts the egg parasitoids, mymarids to suppress the leafhopper.

The tea green leafhopper, Empoasca flavescens is the most important pest of tea plants in China. Mymarid attractants based on herbivore-induced plant volatiles (HIPVs) from leafhopper feeding and oviposition-induced plant volatiles (OIPVs) were formulated and tested as a novel pest control agent against the leafhopper in tea plantations. Results showed that two mymarid species, Stethynium empoascae and Schizophragma parvula, had a reducing effect on leafhopper populations. The HIPVs and OIPVs were identified and bioassayed to screen the key synomones showing strong attraction to the mymarids. They were formulated into different blends, of which Field Attractant 1, comprising linalool, methyl salicylate, (E)-2-hexenal, perillen and α-farnesene at ratio of 1:2:3:58:146 (20 mg/lure), showed the strongest attraction to the mymarids. In field trials with the attractant, the average parasitism rate (60.46 ± 23.71%) of tea leafhoppers by the two mymarids in the attractant-baited area was significantly higher than that (42.85 ± 19.24%) in the CK area. Also, the average leafhopper density (46 ± 30 per 80 tea shoots) in the attractant-baited area was significantly lower than that (110 ± 70 per 80 tea shoots) in the CK area. This study showed that a synthetic blend of key volatiles from HIPVs and OIPVs at an optimal ratio can be formulated into an attractant with the potential to attract and retain wild mymarid populations to suppress leafhopper populations in infested tea plantations, so as to reduce or avoid the spraying of insecticides. © 2023 Society of Chemical Industry.

Intercropping Cover Crops for a Vital Ecosystem Service: A Review of the Biocontrol of Insect Pests in Tea Agroecosystems.

The intercropping of cover crops has been adopted in several agroecosystems, including tea agroecosystems, which promotes ecological intensification. Prior studies have shown that growing cover crops in tea plantations provided different ecological services, including the biocontrol of pests. Cover crops enrich soil nutrients, reduce soil erosion, suppress weeds and insect pests, and increase the abundance of natural enemies (predators and parasitoids). We have reviewed the potential cover crops that can be incorporated into the tea agroecosystem, particularly emphasizing the ecological services of cover crops in pest control. Cover crops were categorized into cereals (buckwheat, sorghum), legumes (guar, cowpea, tephrosia, hairy indigo, and sunn hemp), aromatic plants (lavender, marigold, basil, and semen cassiae), and others (maize, mountain pepper, white clover, round-leaf cassia, and creeping indigo). Legumes and aromatic plants are the most potent cover crop species that can be intercropped in monoculture tea plantations due to their exceptional benefits. These cover crop species improve crop diversity and help with atmospheric nitrogen fixation, including with the emission of functional plant volatiles, which enhances the diversity and abundance of natural enemies, thereby assisting in the biocontrol of tea insect pests. The vital ecological services rendered by cover crops to monoculture tea plantations, including regarding the prevalent natural enemies and their pivotal role in the biocontrol of insect pests in the tea plantation, have also been reviewed. Climate-resilient crops (sorghum, cowpea) and volatile blends emitting aromatic plants (semen cassiae, marigold, flemingia) are recommended as cover crops that can be intercropped in tea plantations. These recommended cover crop species attract diverse natural enemies and suppress major tea pests (tea green leaf hopper, white flies, tea aphids, and mirid bugs). It is presumed that the incorporation of cover crops within the rows of tea plantations will be a promising strategy for mitigating pest attacks via the conservation biological control, thereby increasing tea yield and conserving agrobiodiversity. Furthermore, a cropping system with intercropped cover crop species would be environmentally benign and offer the opportunity to increase natural enemy abundance, delaying pest colonization and/or preventing pest outbreaks for pest management sustainability.

Abundance of Major Insect Pests in Rice and Their Relation to Weather Parameters

The present investigation has been conducted in rice crop during Kharif 2021-22at Students’ Instructional Farm of Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya (U.P.), India. The population of six major insect pests was recorded viz. Rice Yellow stem borer (Scirpophaga incertulus), Rice Leaf folder (Cnapholocrocis medinalis), Rice ear head bug (Leptocorisa acuta), Brown plant hopper (Nilaparvata lugens), White backed plant hopper (Sogatella furcifera)and Green leaf hopper (Nephotettix nigropictus) that cause most damage at different crop growth stages initiated after sowing till harvesting. The maximum population of yellow stemborer was observed on rice crop at 36th SMW (12.20 per cent dead heart). The infestation of dead heart was non-significant positively correlated with minimum, maximum temperature and RH% (0.433, 0.010 & 0.253 respectively) and negatively correlated with rain fall (0.081) whereas, significant negatively correlated with sunshine (0.552*). The maximum population white ear in 40th SMW (16.80 per cent). The infestation of white ear was non-significant negative correlation with minimum, maximum temperature (-0.062, -0.167) and positive correlation with RH & rain fall (0.244 & 0.173) whereas, significant positive correlation with sunshine (0.703*). Maximum leaf folder population was observed during 35th SMW (16.35 per cent). and infestation of leaf folder was non-significant positive correlation with minimum temperature & RH (0.427 & 0.505) and negative correlation with maximum temperature, rainfall and sunshine (-0.079, -0.030 & -0.291). The maximum population was recorded of ear head bug in 38th SMW i.e., (10.90 ear head bug/hill respectively.). The infestation of ear head bug was non-significant positive correlation with minimum temperature, RH, rainfall & sunshine (0.061, 0.176, 0.155 & 0.210) and negative correlation with maximum temperature (-0.407). The peak mean population of BPH was recorded in 37th SMW i.e., (11.25 brown plant hopper/hill respectively.) Itwas non-significant positive correlation with minimum temperature & RH (0.463 & 0.357) and negative correlation with maximum temperature & rainfall (-0.066 & -0.088) whereas, significant negative correlation with sunshine (-0.597*), The peak mean population of WBPH was recorded in 38th SMW i.e., (12.80 white backed plant hopper/hill respectively.) It was non-significant positive correlation with minimum temperature, RH & rainfall (0.300, 0.337 & 0.185) and negative correlation with maximum temperature (-0.300) whereas, significant negative correlation with sunshine (-0.094*) and the maximum population of green leaf hopper was recorded in 37th SMW i.e., (10.80 green leaf hopper/hill respectively.) with the infestation of green leaf hopperwas non-significant positive correlation with minimum temperature & RH (0.479 & 0.369) and negative correlation with maximum temperature & rainfall (-0.077 & -0.120) whereas, significant negative correlation with sunshine (-0.633*).

Endogenous like sequence Rice Tungro Bacilliform Virus (RTBV) fragments in the local rice genome and its role in controlling tungro disease

Tungro disease is one of the important diseases in rice plants because it can cause a large decrease in production. Therefore, tungro disease needs to be controlled in wise ways that ensure environmental sustainability. This can be done by using resistant varieties, while also preventing rice from resistance to the green leafhopper vector Nepothettix virescens, the death of natural enemies, resurgence and emergence of secondary pests which become the main pests. The territory of Indonesia has many very diverse rice germ plasm which its resistance properties can be used to control tungro disease. Resistance genes are an effective control machine especially when combined with other control strategies. One of the triggers for the resistance of rice varieties is eRTBV, which is a group of RTBV nucleotides in rice DNA. The purpose of this study was to detect the presence of the eRTBV piece in the rice genome and its role in controlling tungro disease. The method used wasthe insilico method by comparing the eRTBV found in local rice varieties with that found in Genbank. The results indicated that endogenous RTBV was joined into the rice genome at 1200 bp using the primer eRTBV-7. Nucleotide blast results showed that the similarity of endogenous Indonesian local rice RTBV to endogenous RTBV in the genbank ranged between 95% and 99%, then protein blast results showed that the eRTBV fragment of local rice varieties contained ORF 3 RTBV protein with a range of similarity to the genbank of 66.9% and 93.35%. The role of eRTBV is to produce the Isoleucine protein motif which produces a physical, chemical and biochemical resistance system capable of inhibiting the green leafhopper virus vector (Nepothettix virescens) and the growth and development of tungro disease, RTBV.

Deep CNN-Based Planthopper Classification Using a High-Density Image Dataset

Rice serves as the primary food source for nearly half of the global population, with Asia accounting for approximately 90% of rice production worldwide. However, rice farming faces significant losses due to pest attacks. To prevent pest infestations, it is crucial to apply appropriate pesticides specific to the type of pest in the field. Traditionally, pest identification and counting have been performed manually using sticky light traps, but this process is time-consuming. In this study, a machine vision system was developed using a dataset of 7328 high-density images (1229 pixels per centimetre) of planthoppers collected in the field using sticky light traps. The dataset included four planthopper classes: brown planthopper (BPH), green leafhopper (GLH), white-backed planthopper (WBPH), and zigzag leafhopper (ZIGZAG). Five deep CNN models—ResNet-50, ResNet-101, ResNet-152, VGG-16, and VGG-19—were applied and tuned to classify the planthopper species. The experimental results indicated that the ResNet-50 model performed the best overall, achieving average values of 97.28% for accuracy, 92.05% for precision, 94.47% for recall, and 93.07% for the F1-score. In conclusion, this study successfully classified planthopper classes with excellent performance by utilising deep CNN architectures on a high-density image dataset. This capability has the potential to serve as a tool for classifying and counting planthopper samples collected using light traps.

Genetic polymorphism and plant growth promotion traits of potent fungal entomopathogens of rice leaf folder.

Entomopathogenic fungal biocides are preferred for environment friendly sustainable management of insect pests due to their host specificity and harmlessness to non-target insects. Plant growth promotion (PGP) functions of the entomofungi are also important attributes but hitherto insignificantly explored. Therefore, virulence of 17 natural fungal entomocides (Cordyceps, Beauveria, Metarhizium, Nomuraea, Fusarium, Verticillium, Trichoderma and Paecilomyces spp.) were evaluated for pathogenicity against five rice pests (brown plant hopper (Nilaparvata lugens) and green leaf hopper (Nephotettix virescens) nymphs, leaf folder (Cnaphalocrosis medinalis) and yellow stem borer (Scirpophaga incertulas) larvae and swarming caterpillar (Spodoptera mauritia), respectively), and PGP traits of the potent leaf folder pathogens. Among the fungi, only the leaf folder pathogens (3 isolates each of Beauveria and Metarhizium spp.) infected > 50% (80-90%) larvae but other fungi were ineffective as infected < 50% (0-47%) insects. Besides, the leaf folder pathogens exhibited diverse PGP traits such as organic/inorganic phosphate solubilization (104.7-236.4µg/ml), and siderophore, ammonia, hydrogen cyanide (HCN), indole production etc. Restriction fragment length polymorphism (RFLP), random amplified polymorphic DNA (RAPD), simple sequences repeat (SSR) and internal transcribed spacers (ITS) analysis ascertained strain identity and genetic (inter and intra-specific) diversity among the potent biocides Beauveria and Metarhizium spp. The virulent natural fungal pathogens of rice pests with polyvalent PGP traits may be prospected for rice growth promotion and biocontrol of leaf folder.

Salibu Rice Cultivation in Tungro Endemis Region

Salibu is modified ratoon rice which has advantages in economic and time-saving. Tungro disease is one of probable handicap for salibu to be controlled in their endemic area. Rice virus tungro disease is caused by Rice Tungro Bacilliform Virus (RTBV) and Rice Tungro Spherical Virus (RTSV) which are transmitted by leafhopper. The research goals are to know the growth of leafhopper population and the spread of the tungro disease in salibu and conventional rice farming system as well as their effect on yield. The research was conducted in split plot experiment and designed in a randomized block design. The main plot were 1) salibu system and 2) conventional system (non-salibu). The subplots were varieties 1) TN1 (sensitive variety), 2) Ciherang (commonly used by the farmer), and 3) Inpari 36 (tungro new resistant variety). The results revealed that the tungro attack rate, dry milled grain yield, and 1000 dry grain weight were significantly higher in conventional cultivation than salibu (P &lt; 0.05). The number of leafhopper populations tended to be higher in salibu system than in conventional system. The number of natural enemies did not show a particular pattern related to green leafhopper's presence. The Shannon Wiener diversity index for natural enemies ranged from low to medium. Regarding to the results, salibu system is not recommended yet in the tungro endemic areas. Keywords: Salibu, rice tungro virus disease, green leafhopper, natural enemies

Evaluation of Botanicals Insecticide against Stem Borer Scirpophaga incertulas (Walker) Leaf Folder (Cnaphalocrosis medinalis) and Green Leafhopper and in Rice

A field experiment was conducted during the kharif season of 2020-21 and 2021-22 at Crop Research station, Masodha, Ayodhya, India to evaluate the efficacy of insecticide-botanicals against rice stem borer, green leafhopper and leaf folder. The experiment was comprising Four combination modules/treatments consisting of three insecticides Chlorantraniliprole 20% SC, Cartap hydrochloride 50% SC and Triflumezopyrim 10% SC, one commercial neem formulation - Neemazal and two plant oils - Neem and Eucalyptus oil procured were compared along with untreated control (only water spray). The lowest stem borers incidence (1 %) of in all insecticides treatment module recorded as compared to 14.8% in untreated control. Among modules, all insecticides module was found to be the best with 1.0% mean white ear damage followed by neemazal, eucalyptus oil and cartap hydrochloride module with 5.3% WE. Green leafhopper infestation was all insecticides combination was the most effective treatment showing mean population of 110.7/10 hills followed by all botanical combination (120.7) and were superior to control (158.7/10 hills). The mean leaf Folder damage (1.8%) was recorded from all insecticides module followed by treatment with neemazl (? %), Eucalyptus oil (? %), and Triflumezopyrim 10% SC (3.9% DL) when compared to untreated control (14.5% )4. Grain yield all insecticides treatment - Chlorantraniliprole, Cartap hydrochloride, Triflumezopyrim recorded the highest grain yield of 5212.0 kg/ha with 95.79% increase over control (IOC) followed by neemazal, neem oil and cartap hydrochloride with 4500 kg/ha (69.04% IOC). All the treatments were significantly superior to control plot which showed a yield of 2662 kg/ha.

Involvement of three chemosensory proteins in perception of host plant volatiles in the tea green leafhopper, Empoasca onukii.

Chemosensory proteins (CSPs) can bind and transport odorant molecules, which are believed to be involved in insect chemoreception. Here, we investigated three CSPs in perception of volatiles in Empoasca onukii. Expression profiles showed that although EonuCSP4, EonuCSP 6-1 and EonuCSP6-2 were ubiquitously expressed in heads, legs, thoraxes and abdomen, they were all highly expressed in the antennae of E. onukii. Further, fluorescence competitive binding assays revealed that EonuCSP4 and 6-1 had binding affinities for three plant volatiles, suggesting their possible involvement in the chemosensory process. Among them, EonuCSP6-1 showed relatively high binding affinities for benzaldehyde. Behavioral assays revealed that the adults of E. onukii showed a significant preference for two compounds including benzaldehyde. The predicted three-dimensional (3D) structures of these 3 CSP have the typical six α-helices, which form the hydrophobic ligand-binding pocket. We therefore suggest that Eoun6-1 might be involved in the chemoreception of the host-related volatiles for E. onukii. Our data may provide a chance of finding a suitable antagonist of alternative control strategies which block the perception of chemosensory signals in pest, preventing the food- orientation behaviors.

Transcriptome and co-expression network analysis uncover the key genes mediated by endogenous defense hormones in tea plant in response to the infestation of &lt;i&gt;Empoasca onukii&lt;/i&gt; Matsuda

The tea green leafhopper [<italic>Empoasca</italic> (<italic>Matsumurasca</italic>) <italic>onukii</italic> Matsuda] is one of the most dominant pests in the tea production regions of China, greatly impacting tea yield and quality. Extensive studies have attributed the plant defense response to pest infestation to the activation of hormone signals, but the role of defense hormones in tea plants in response to the feeding of <italic>E. onukii</italic> is not clear. RNA-seq was performed on the leaf samples collected at different time points (6, 24 and 48 h) after feeding with <italic>E. onukii</italic> to explore the transcription characteristics of tea plant responses to feeding. The content variation characteristics of four phytohormones (JA, JA-Ile, ABA and SA) during this process were also determined. The results showed that feeding elevated the expression of key genes involved in phenylpropanoid biosynthesis, flavonoid biosynthesis, α-linolenic acid metabolism and terpenoids synthesis pathways, especially in the early stage after feeding. The contents of JA, JA-Ile, and ABA dramatically increased at different time points after feeding, but the absolute content decreased over time. The change in the absolute content of SA was opposite to that of the above three hormones. Two gene co-expression networks that were significantly positively associated with these hormonal changes were constructed based on WGCNA. The screened hub genes provide useful genetic resources for exploring the hormone-mediated defense responses of tea plants against <italic>E. onukii</italic>. Our results lay the foundation for the ecological control of <italic>E. onukii</italic> and breeding of resistant tea plant cultivars.

Padat Populasi Wereng Batang Coklat (Nilaparvata lugens) dan Wereng Hijau (Nephotettix virescens ) pada Tanaman Padi Varietas Inpara 2 di Kampung Bokem Kabupaten Merauke Papua

The purpose of this study was to analyze the population density and intensity of attack of Brown Planthopper (Nilaparvata lugens Stall) and green leafhoppers (Nephotettix virescens) on rice plants of Inpara 2 variety in Bokem Village. The research was conducted from August to October 2022 in the rice fields of Bokem Village, Merauke District. Sampling was carried out on three rice fields with an area of 20 x 40 m divided by five observation sub-plots spread diagonally with a size of 2 x 2 meters. Plant height of Inpara 2 variety at the age of 14 DAP (23.1 cm), 28 DAP (33.2 cm), 42 DAP (53.8 cm), 56 DAP (64 cm) and 70 DAP (70.2 cm) . The number of tillers at the age of 14 days old (3.2 tillers), 28 days old (5.5 tillers), 42 days old (11 tillers) and 56 days old (12.1 tillers). The panicle length of the Inpara 2 rice variety was on average (21.1 cm) while the weight of 1000 grains was 14.7 grams. Brown planthopper population at the age of 14 days after planting (0.19 individuals), 28 days after birth (0.07 individuals), 42 days after birth (0.19 individuals) and 56 days after planting (0.31 individuals) while the green leafhopper population at 14 days old (0.30 individuals) 32 individuals), 28 days old (0.33 individuals), 42 days old (0.25 individuals) and 56 days old (0.01 individuals). Keywords: Pest, Inpara 2, Population, Brown planthopper, green leafhoppers