Planthopper Research Articles

Bio-efficacy of new insecticidal molecules against plant hoppers in rice crop

The study was carried out during kharif seasons of 2020 and 2021 at different locations to assess the relative bioefficacy of new insecticidal molecules viz. Pexalon 10 SC (triflumezopyrim), Osheen 20 SG (dinotefuran), Chess 50 WG (pymetrozine) and Confidor 200 SL (imidacloprid) @ 235 ml, 500, 300 and 100 gm per hectare, respectively against plant hoppers (brown plant hopper and white backed plant hopper) in rice crop. The population of plant hoppers per hill was recorded before spray, 3, 7 and 10 days post treatment periods. It has been observed that all tested molecules are found significantly better and reduced (90.63-88.75%) the plant hoppers’ population over control. Among, insecticidal treatments Osheen 20 SG showed superiority with least plant hoppers population [(1.10, 0.55, 0.56 (av. 0.74)] per hill and it was at par with each other insecticidal molecules. The maximum grain yield (72.45 q/ha) was obtained with application of Osheen 20 SG, however the highest cost: benefit (Rs. 1: 23) was achieved with application of Confidor (100 ml/ha). It was further observed that all the tested molecules have no ill effects on spider’s population (Natural enemies).

The dynamic of pests and plant diseases during three consecutive rice growing seasons

Pests and diseases are significant factors that affecting global rice production. There is a need that pests and diseases have continuously been controlled, in order to solve the pest and disease problem. The aim of this study was to observe the population dynamics of pests and diseases infestation in lowland rice field during different cropping seasons. The data of pest and disease infestation in Pati District, Central Java Province, Indonesia during the Rainy Season (RS) 2018/2019, the Dry Season (DS) 2019, and the RS 2019/2020 were observed and analyzed. The results showed that the rice fields in Pati were susceptible to stem borer, brown plant hopper, rats, fake white pests, blast and bacterial blight during three consecutive seasons. Tungro was not found. During both the RS and DS, the areas of rice paddy in Pati approximately 470 ha season−1 were affected by stem borer. The second largest damage rice area approximately 221 ha season−1 was affected by blast. Grain loses due to pests and diseases infestation during the RS was higher than during the DS. Micro-climate significantly affected pests and plant diseases. The dynamic of pests and plant disease infestation provide information early warning for high-risk areas of rice production and for pests-diseases management.

Effect of Crop Growth Stages on the Field Population of Rice Hoppers

The rice hoppers viz., brown plant hopper (BPH) Nilaparvata lugens (Stal), white-backed planthopper (WBPH) Sogatella furcifera (Horvath) and green leafhopper (GLH) Nephotettix virescens Distant cause loss in rice and the damage is influenced by plant growth stages. Field experiment has been conducted in this study to evaluate the effect of the growing stages on the incidence of these hoppers at the Agricultural Research Farm, Banaras Hindu University, Varanasi, Uttar Pradesh, India during kharif 2018 and 2019. The results revealed that the incidence is significantly varying among the growth stages, and positively correlated (p < 0.05). Nilaparvata lugens and S. furcifera are the most abundant during the maximum tillering to booting stage. In contrast that of N. virescens peaked during the booting to flowering stage.

Volatile Profiles as Affected by Rice Brown Plant Hopper and Yellow Stem Borer in Rice Landraces

Rice (Oryza sativa L.,) plants release a complex profile of volatile organic compounds. Present study investigates the differences in volatile compounds from four rice landraces viz., Karuthakar, Norungan, Thavala Kanan and Varappu Kudaichan each under four conditions like healthy, mechanically damaged, and the ones infested by the brown plant hopper Nilaparvata lugens Stal and yellow stem borer Scirpophaga incertulas (Wlk.). The volatiles were collected using air entrainment method and characterized by the GCMS. Statistical analysis tools like clustering, principal component analysis and partial least square discriminant analysis were applied. Clear differences among the treatments were observed and certain volatile compound groups like terpenoids (squalene), unsaturated fatty acids (n-hexadecanoic, tetradecanoic and pentadecanoic acids), alkanes (heptacosane, tetracosane) were found. The statistical test of Partial Least Square Discriminant Analysis was found to be satisfactory in determining the compounds responsible for variations in treatments.

Diversity of leaf hoppers on fruit crops and weeds in North Kashmir

This study analyses the diversity of leafhopper fauna at six locations (Wadura, Arampora, Dangiwacha, Imberzalwari from District Baramulla and Chogul and Chetkak from District Kupwara) occurring on various fruit crops and weeds. Diversity indices such as species diversity index, evenness index, richness index and abundance were computed. These reveal that six species infest these, of which those infesting fruit trees include Empoasca decipiens, Empoasca fabae, Agallia spp., Aconeurella erebrus and Exitianus indicus; and Stirellus spp., Maiestas dorsalis, Macrosteles quadrilineatus, Exitianus indicus and one plant hopper species viz., Laodelphax striatellus infest weeds. Maximum abundance was observed to be of A. decedens on fruit trees and Stirellus spp. on the weed flora.

Damage of brown planthopper (BPH) Nilaparvata lugens and rice leaf folder (LF) Cnaphalocrocis medinalis in parent plants lead to distinct resistance in ratoon rice

ABSTRACT Herbivore-induced defense responses are often specific, whereas plants could induce distinct defense responses corresponding to infestation by different herbivorous insects. Brown plant hopper (BPH) Nilaparvata lugens, a phloem-feeding insect, and rice leaf folder (LF) Cnaphalocrocis medinalis, a chewing insect, are both specialist herbivores on rice. To characterize the distinct resistance primed by prior damage to these two specialist herbivores, we challenged rice plants with two herbivores during vegetative growth of parent plants and assessed plant resistance in subsequent ratoons. Here, we show that LF and BPH induce different suites of defense responses in parent rice plants, LF induced higher level of JA accumulation and OsAOS, OsCOI1 transcripts, while BPH induced higher accumulation of SA and OsPAL1 transcripts. Moreover, an apparent loss of LF resistance was observed in OsAOS, OsCOI1 RNAi lines. Ratoon plants generated from parents receiving prior LF infestation exhibited higher jasmonic acid (JA) levels and elevated levels of transcripts of defense-related genes associated with JA signaling, while ratoon generated from parents receiving prior BPH infestation exhibited higher salicylic acid (SA) levels and elevated levels of transcripts of defense-related genes associated with SA signaling. Moreover, previous LF infestation obviously elevated ratoons resistance to LF, while previous infestation by BPH led to enhanced resistance in ratoons to BPH. Pre-priming of ratoons defense to LF was significantly reduced in OsAOS and OsCOI1 RNAi plant, but silencing OsAOS and OsCOI1 did not attenuate ratoons resistance to BPH. These results suggest that infestation of two specialist herbivores with different feeding styles in parent crop led to distinct defense responses in subsequent rations, and the acquired resistance to LF in ratoons is associated with priming of jasmonic acid-dependent defense responses.

Does solar light trap reduce the cost of pesticides used in rice field?

Pesticide application against insect pest infestation is environmentally unsafe and costly. An attempt was taken to evaluate the solar light trap as ecofriendly and cost-effective approach in Transplanted Aman rice (BRRI dhan32) field at Barhatta Upazila (Sub-district) in Netrokona district of Bangladesh. It was found that rice pest like Rice yellow stem borer, Rice leaf roller, Green leaf hopper, Brown plant hopper, Rice leaf miner, Rice gall midge, White leafhopper, Rice bug, Rice ear cutting caterpillar, White-backed planthopper, Rice caseworm, Grasshopper, Rice skipper and Rice beetle were the major insects that captured under the solar light traps. Some beneficial insects were also attracted by the trap these were Ladybird beetle, Water scavenger, Giant water bug, Ground beetle, Rove beetle, Damsel fly. All the harmful and the beneficial insects were belonging the order of Lepidoptera, Hemiptera, Orthoptera, Coleoptera, Diptera and Odonata. Though the mean yield of rice was statistically insignificant in both fields, the light trap installed fields required the less frequency of pesticides than the control fields which ultimately rendered the low pesticides cost in a great extent. On an average 1,034 BDT was reduced in per hectare. SAARC J. Agric., 20(1): 171-183 (2022)

Novel Formulation of Herbal Pesticide for Rice Cultivation

The irrational use of chemical pesticides has caused serious health hazards and environmental problems in developing countries including India. Hence, the Present investigation was carried out to formulate an effective Herbal pesticide against three major pests of rice like stem borers, leafhoppers and plant hoppers and to find solution for control of pest population by traditional agricultural practices. Oil of Azadirachta indica, Vitex nigundo, Ipomoea carnea, Adhatoda zeylanica and natural surfactant are the main constituents used in the formulations. Larvae of stem borers in the infected stem and hopper damaged part of the plant were selected for the study. A total of six herbal formulations at four different concentrations were sprayed on larvae of stem borers and hopper damaged parts of plants. The developed herbal pesticides have been validated in the field as well as in lab conditions and larval mortality rates were observed. After treatment, the population of pests decreased gradually and the mortality rate of larvae increased. Herbal pesticides focus on providing solutions and relief from various types of insects that cause massive damages to the plants being grown on a farm. These products were made of natural materials that have properties of killing or keeping out pests within the range of the field. The results showed that the extent of growth of these pests was less when compared to control and minimum occurrence of pest attack and Percent Dead Heart (DH) was confirmed in response to herbal formulations. The foremost benefit of this herbal pesticide is managing the Yellow Stem Borer (YSB) pest population and providing healthier cropping systems. Hence it is recommended to use this herbal pesticide for disease free sustainable cultivation of organic rice.

Novel Formulation of Herbal Pesticide for Rice Cultivation

The irrational use of chemical pesticides has caused serious health hazards and environmental problems in developing countries including India. Hence, the Present investigation was carried out to formulate an effective Herbal pesticide against three major pests of rice like stem borers, leafhoppers and plant hoppers and to find solution for control of pest population by traditional agricultural practices. Oil of Azadirachta indica, Vitex nigundo, Ipomoea carnea, Adhatoda zeylanica and natural surfactant are the main constituents used in the formulations. Larvae of stem borers in the infected stem and hopper damaged part of the plant were selected for the study. A total of six herbal formulations at four different concentrations were sprayed on larvae of stem borers and hopper damaged parts of plants. The developed herbal pesticides have been validated in the field as well as in lab conditions and larval mortality rates were observed. After treatment, the population of pests decreased gradually and the mortality rate of larvae increased. Herbal pesticides focus on providing solutions and relief from various types of insects that cause massive damages to the plants being grown on a farm. These products were made of natural materials that have properties of killing or keeping out pests within the range of the field. The results showed that the extent of growth of these pests was less when compared to control and minimum occurrence of pest attack and Percent Dead Heart (DH) was confirmed in response to herbal formulations. The foremost benefit of this herbal pesticide is managing the Yellow Stem Borer (YSB) pest population and providing healthier cropping systems. Hence it is recommended to use this herbal pesticide for disease free sustainable cultivation of organic rice.

Efficacy of a New Combination Insecticide Against Rice Brown Planthopper <i>Nilaparvata Lugens</i> (Stal)

Efficacy of a new combination insecticide against rice brown plant hopper (BPH) Nilaparvata lugens Stal revealed that among all the treatments, significant reduction in the incidence (76.91% reduction over control) and higher grain yield (5.37 ton/ ha) was obtained with buprofezin 24%+ fipronil 40%SC (MAIRM-10) @ 875 ml/ ha. It was at par with buprofezin 24%+ fipronil 40%SC (MAIRM-10) @ 750 ml/ ha followed by buprofezin 25%SC @ 800 ml/ ha. Although maximum grain yield was obtained from buprofezin 24%+ fipronil 40%SC (MAIRM-10) @ 875 ml/ ha, maximum cost benefit in term of ICBR was observed with buprofezin 24%+ fipronil 40%SC (MAIRM-10) @ 750 ml/ ha (1:6.11) besides considering the environmental effect. Buprofezin 24%+ fipronil 40%SC (MAIRM-10) @ 750 ml/ ha was found to be most optimum one for BPH management.

Sustainability and impact assessment of IPM in Basmati rice (Oryza sativa)

Integrated pest management (IPM) strategy has greatly contributed to a progressive commitment for sustainable agriculture in India. Long term studies conducted on validation and promotion of IPM in basmati rice (Oryza sativa L.) in district Gautam Budh Nagar, Uttar Pradesh, India resulted in a gradual enhancement in the area under IPM from 40 ha in 2010 by participation of 25 farmers to 990 ha in 2019 by participation of 654 farmers from 42 villages. Implementation of IPM technology resulted in a significant (P<0.05) reduction in the incidence of yellow stem borer (69.64%), leaf folder (70.9%), brown plant hopper (55.52%), bakane (90.98%) and the population of root-knot nematode (76.8%) over farmers’ practices (FP). It enhanced the population of predatory spiders (84.2%), beneficial soilnematodes (159.27%) and bio-agents, viz. Pseudomonas fluorescens (78.74%) and Trichoderma harzianum (81.34%) over FP. Application of chemical pesticides was reduced to 75.25 g/ha in IPM against 892.93 g/ha in farmers’ practice. The maximum residue level of buprofezin, a widely used insecticide, was recorded below detectable level in paddy grains. Long term studies indicated higher yield (38.0 q/ha) as well as benefit:cost ratio (3.6) in IPM as compared to FP yield (30.5 q/ha) and benefit:cost ratio (2.3) with 58.3% enhancement in net return over FP. Thorough analysis of the data indicated the availability of critical inputs, accessibility of farmers to subject matter specialists through Farmer Field Schools and market for IPM produces as the main factors responsible for sustainability and horizontal spread of IPM in Gautam Budh Nagar.

Comparative efficacies of modules against major insect pests and natural enemies in rice (Oryza sativa)

A field experiment was conducted at regional Research and Technology Transfer Station (OUAT), Chiplima,Sambalpur, Odisha, during rainy season (kharif) 2019–20 to determine the comparative efficacies of variousinsecticides and botanicals modules against major insect pests and natural enemies of rice (Oryza sativa L.). Therewere 9 modules and overall data revealed that the all the treated plots recorded significantly lower per cent of deadheart; white ear-head caused by stem borer; silver shoot caused by gall midge; leaf folder infested leaves and planthoppers. Among them, module consists of fipronil 5 sc @1500 ml/ha at 25–30 DAT, rynaxypyr 20 sc @150 ml/ha at45–50 DAT and triflumezopyrim 106 sc @240 ml/ha at 65–70 DAT treated plot recorded significantly higher per centreduction of stem borer infestation, leaf folder, plant hoppers and produced higher grain yield than the other modules as well as highest benefit cost ratio B : C (1.89) and next best was carbosulfan 25 ec @875 ml/ha, rynaxypyr 20 sc @150 ml/ha and flonicamid 50 wg @150 g/ha containing module. So, the module containing fipronil, rynaxypyr and triflumezopyrim may be adopted for the effective management of major insect pests of rice and helps the farmers from unwanted spraying of insecticides many times.

Brown Plant Hopper and Blast to environmental friendly of rain-fed rice in Yogyakarta

Abstract There is a challenge to increase the productivity of rain-fed rice in Yogyakarta. However, brown plant hopper and blast disease are the main constraint. Tolerant varieties are suggested due to its environmental friendly to increase rice yield. This research was aimed to determine the population of brown plant hopper and blast disease as the effect of varieties improvement in increasing rain-fed rice productivity. Research was conducted in Nglipar Gunungkidul Yogyakarta, from September 2018 to January 2019. Experimental design was randomized block design with 6 treatments and 4 replications. The treatments were six rain-fed rice varieties (Inpago 8, Inpago 10, Inpago 12, Inpago Unsoed, Rindang 1, and Rindang 2) with two control varieties (Inpari 42 and Ciherang). Results showed that Brown Plant Hopper population and blast disease intensity in Inpago 10, Inpago 12, and Inpago Unsoed were lower than in other varieties. Yield of Inpago 8, Inpago 10, Inpago 12, Inpago Unsoed, Rindang 1, Rindang 2, Inpari 42 and Ciherang were 6.20, 7.37, 7.01, 7.49, 6.20, 6.84, 6.97, and 4.00 ton ha-1, respectively. Varieties improvement resulted higher rice productivity compared to Ciherang as existing variety in farmers practices.

Wild Rice Species in Sri Lanka as Genetic Resources for Breeding for Brown Plant Hopper (<em>Nilaparvata lugens</em> (Stål)) Resistance in Rice

Brown pl anthopper (BPH) Nilaparvata lugens (Stål.) is considered the most destructive rice pest in rice-growing countries including Sri Lanka. Resistance breeding considered the most e conomical management strategy, starts by identifying new genetic resources for BPH resistance and comparative analysis wi th existing donors. So far, scientists have identified 38 genes/QTLs responsible for BPH resistance. This study explored the BPH resistance in five wild rice species in Sri Lanka, inc luding the endemic species Oryza rhizomatis. One recommended rice variety; Bg 352, fourteen O. rhizomatis accessions, and one accession from Oryza nivara, Oryza rufipogon, Oryza granulata and Oryza eichingeri screened by the honeydew test. The experiment was arranged in a complete randomize d design with fifteen replicates with Bg 380 and Ptb 33 as susc eptible and resistant checks respectively. The lower amount of honeydew excretion recorded in all tested O. rhizomatis accessions, O. nivara, O. granulata, and O. eichingeri accessions suggested BPH resistance. Both Ptb 33 and O. rufipogon showed a similar level of resistance with low honeydew excretion. The varieties Bg 352 and Bg 380 showed a high amount of honeydew excretions confirming higher susceptibility to the BPH. Therefore, all fourteen accessions of O. rhizomatis and the selected accessions of O. nivara and O. eichingeri are potential donors for rice breeding programs. Further, th e coding sequences (CDS) of known BPH genes of O. sativa were used as queries to search similar genes in wild rice genomes. The CDS coverage and phylogenetic analysis suggest, of known BPH resistance genes, at least BPH6, BPH9, BPH14-1, and BPH18 are present in O. rhizomatis, O. eichingeri, O. nivara, and O. rufipogon genomes. This information will assist in marker-as sisted breeding attempts.

Genomic analysis and finding of candidate genes for Nilaparvata lugens (stål) resistance in Indian pigmented and other indigenous rice genotypes

Rice production is facing serious threats due to frequent outbreak of brown plant hopper, Nilaparvata lugens (Stål.) population. Globally, four biotypes of N. lugens has been recorded, of which biotype-4 is the utmost damaging one prevailing in Asian subcontinents particularly in India. Therefore, effective management of N. lugens requires durable resistant rice variety with multiple resistant traits and genes. Hence, in the present study 268 rice genotypes were screened against N. lugens. From initial screening results, 96 genotypes were selected for further genotyping using 93 molecular markers linked to 26 different N. lugens resistant (R) genes. Genetic analysis revealed the mean genetic diversity of 0.275 and polymorphic information content of 0.240 for all 93 markers. Genetic association through cluster and population structure analysis clearly differentiated the 96 genotypes into three major genetic groups with resistant genotypes grouped in a separate cluster. Likewise, Principal co-ordinate analysis supported the above claim with susceptible, moderately resistant and resistant genotypes accommodated in separate components. Further, genetic variation among population showed a 92% variation among individuals of the population and only 8% between populations. Marker trait association via generalized linear model (GLM) and multi linear model (MLM) picked out five markers for their significant association with different phenotypic parameters such as percent damage, nymphal survival, feeding mark and honeydew excretion. Three markers viz. RM19291 (Bph30), RM28472 (Bph18) and RM28449 (Bph17) were common for both GLM and MLM analysis. These identified resistant genes in rice landrace will serves as the source for development of durable resistant variety against N. lugens.

Bio-efficacy of insecticide and fungicide mixtures against leaf folder, stem borer, BPH and sheath blight of rice

Bio-efficacy assessment with four insecticides and two fungicides was carried out in Agricultural College farm, Naira during kharif, 2019 against leaf folder, stem borer, brown plant hopper (BPH) and sheath blight of rice. The treatments include four insecticides [Flonicamide 50 WG (0.4 g/l), Pymetrozine 50 WG (0.6 g/l), Chlorantraniliprole 18.5 SC (0.3 g/l), Acephate 75 SP (1.5 g/l)], two fungicides [(Difenoconazole 25 EC (0.5 ml/l), Azoxystrobin 23 EC (0.75 ml/l] and Untreated Control. Results indicated that treatment Chlorantraniliprole 18.5 SC (0.3 g/l) was effective against leaf folder (per cent leaf folder damage: 3.29) and stem borer (% DH: 1.17, % WE: 2.11) which was on par to both of its fungicide combinations viz., Azoxystrobin 23 EC (0.75 ml/l) (per cent leaf folder damage: 3.02, % DH: 1.29, % WE: 2.51) and Difenoconazole 25 EC (0.5 ml/l) (3.85, 1.76, 2.64). Against brown planthopper, treatment Pymetrozine 50 WG + Difenoconazole 25 EC (0.6 g/l + 0.5 ml/l) (reduction over control- 92.95%) was effective and pertinent to sheath blight, treatment chlorantraniliprole + azoxystrobin (PDI: 5.14) along with all the four test insecticide combinations of azoxystrobin proved their best.

Multiparent-Derived, Marker-Assisted Introgression Lines of the Elite Indian Rice Cultivar, 'Krishna Hamsa' Show Resistance against Bacterial Blight and Blast and Tolerance to Drought.

Major biotic stresses viz., bacterial blight (BB) and blast and brown plant hopper (BPH) coupled with abiotic stresses like drought stress, significantly affect rice yields. To address this, marker-assisted intercross (IC) breeding involving multiple donors was used to combine three BB resistance genes—xa5, xa13 and Xa21, two blast resistance genes—Pi9 and Pi54, two BPH resistance genes—Bph20 and Bph21, and four drought tolerant quantitative trait loci (QTL)—qDTY1.1, qDTY2.1, qDTY3.1 and qDTY12.1—in the genetic background of the elite Indian rice cultivar ‘Krishna Hamsa’. Three cycles of selective intercrossing followed by selfing coupled with foreground selection and phenotyping for the target traits resulted in the development of 196 introgression lines (ILs) with a myriad of gene/QTL combinations. Based on the phenotypic reaction, the ILs were classified into seven phenotypic classes of resistance/tolerance to the following: (1) BB, blast and drought—5 ILs; (2) BB and blast—10 ILs; (3) BB and drought—9 ILs; (4) blast and drought—42 ILs; (5) BB—3 ILs; (6) blast—84 ILs; and (7) drought—43 ILs; none of the ILs were resistant to BPH. Positive phenotypic response (resistance) was observed to both BB and blast in 2 ILs, BB in 9 ILs and blast in 64 ILs despite the absence of corresponding R genes. Inheritance of resistance to BB and/or blast in such ILs could be due to the unknown genes from other parents used in the breeding scheme. Negative phenotypic response (susceptibility) was observed in 67 ILs possessing BB-R genes, 9 ILs with blast-R genes and 9 ILs harboring QTLs for drought tolerance. Complex genic interactions and recombination events due to the involvement of multiple donors explain susceptibility in some of the marker positive ILs. The present investigation successfully demonstrates the possibility of rapid development of multiple stress-tolerant/resistant ILs in the elite cultivar background involving multiple donors through selective intercrossing and stringent phenotyping. The 196 ILs in seven phenotypic classes with myriad of gene/QTL combinations will serve as a useful genetic resource in combining multiple biotic and abiotic stress resistance in future breeding programs.

Seasonal variation in population and biochemical contents of brown planthopper, Nilaparvata lugens (Stål)

Aim: The present study was undertaken on population dynamics and estimation of protein, water-soluble carbohydrates and glycogen contents in the brown planthopper, Nilaparvata lugens to explore their migratory behaviour. Methodology: Brown planthopper populations were monitored and collected using sweep nets from 23rd standard meteorological week (SMW) to 47th SMW during 2017 and 2018 rainy seasons to understand population dynamics of the pest. The protein, water-soluble carbohydrates and glycogen contents were estimated from the pest samples collected during 36th to 44th SMW in 2017 and 2018 rainy seasons. Results: Brown planthopper population were not observed in rice farm during 23rd SMW to 28th SMW during two years of study. However, macropterous form of the pest first appeared in the farm during 29th SMW and peaked during 43rd SMW. Thereafter, population declined and disappeared after 47th SMW during both the years. Water-soluble carbohydrates and glycogen contents varied significantly different weeks which remained low during 36th-39th SMW, however, increased gradually towards the end of the rainy season 2017 and 2018. On the other hand, protein content significantly varied among different weeks unlike the trend of water-soluble carbohydrates and glycogen. Interpretation: The study revealed the absence of brown plant hopper during summer season preceding rainy season, and the accumulation of bio-chemical compounds towards the end of rainy season under Delhi environment is perhaps suggestive of migration of the pest from unknown areas during rainy season to Delhi and likely preparedness of the pest for emigration to safer areas from Delhi, respectively.

Efficacy of dinotefuran 20 SG against brown planthopper (Nilaparvata lugens Stål) in basmati rice

Brown planthopper, Nilaparvata lugens StÃ¥l is a dominant species among the noxious rice pests and causes considerable damage in India. Various strategies have been employed to manage brown planthopper and insecticides factor as the frontline defense. However, it has now become difficult to manage brown planthopper with the present genre' of insecticides due to the development of resistance. Identification of new molecules with selective properties, a novel mode of action, low toxicity to non-targets and environmental safety becomes a newer tool for the sustainable management of brown planthopper. In this direction, dinotefuran 20 SG a new molecule was evaluated under field conditions to access its efficacy against brown planthopper in basmati rice during Kharif, 2019. Results of the present investigations indicated that dinotefuran 20 SG at 40 g a.i./ha as a spray (when pest crosses ETL) was  the effective treatment in the reduction of brown plant hopper population. The added advantages included non phytotoxicity of foliar application of dinotefuran 20 SG @ 40  g a.i. ha-1 to the paddy crop. Mean  grain yield (38.1  q ha-1) was recorded in dinotefuran 20 SG sprayed plots as compared to control (32.3 q ha-1) and increase in grain yield over control was recorded to be 15.5 per cent.Â

DOWNLOAD PDF DOWNLOAD XML Chemical Pesticide Use Pattern, Status And Farmer’s Awareness In Rice Growing Areas Of Khajura, Nepal

A study was carried out during the summer in rice growing areas of Khajura rural municipality, Banke to evaluate the use pattern, status of chemical pesticide, problematic insects/pests in rice and farmers level of awareness for use of chemical pesticides. For the study, the household selection was done via simple random sampling among major rice growing household. All together 40 rice growing were selected and the data was collected, tabulated and frequency percentage were derived to present the results. The study revealed that age, sex, family type and education level all had significant influence on the selection of pest control strategies. Stem borer, Gundi bug, Plant hoppers and moths were reported to be the major pest in rice in the study area. Chemical method of pest control was the most dominantly adopted strategy among the respondent where they get the usage information from the Agro-vets and the extension workers. Respondents were aware of the health hazard caused by the chemical usage and majority of them picked headache and eye problem as the major ones. Farmers mostly used pesticide during panicle initiation stage and were found less attracted to other method of pest control as they lack sufficient knowledge on other control strategies. Usage of safety equipment was very low among the farmers during the pesticide spray however use of boots and mask were found to be common. Farmers totally ignored the preparation directions, pesticide labels and disposal instructions and not aware of the waiting period.