Agro-climatic Zones Of West Bengal Research Articles

Influence of cropping sequences on soil suppressive/conduciveness against Sclerotium rolfsii in different agro-climatic zones of West Bengal, India

Aim: To study the influence of different cropping sequences (CSs) on soil suppressive or conduciveness towards Sclerotium rolfsii in different agro-climatic zones (ACZs) of West Bengal, India. Methodology: Farmer’s field surveys were conducted to explore the suppressive activity of various crop rhizosphere during each winter, October to January (2016-2019). The survey was done in 14 districts of five ACZs in West Bengal (India), and the total surveyed sample size was 511. The S. rolfsii disease incidence (DI%) data of Rabi crop in surveyed areas and sclerotial population, soil suppressive index, FDA hydrolysis, dehydrogenase activity and culturable microbial assay were performed. Results: In this data set (n=511), the foremost soils belonged to no suppressive category (74.47%), followed by slight suppressive category (20.74%). Negligible number of soils belonged to moderate (0.39%) and strong suppressive (0.39%) category. The population of Pseudomonads was higher in both strong and moderate suppressive soil rather than slight and no suppressive soils. Culturable population of soil Pseudomonads, Bacillus and Actinomycetes varied in five different ACZs. Interpretation: Paddy-brassica vegetables, paddy-maize and paddy-cucurbits vegetable-based CSs exhibited relatively high soil uppressiveness whereas paddy-legumes, jute-paddy-legume vegetables and pulses based CSs showed high soil conduciveness towards S. rolfsii. Soil microbial influences on crop rhizosphere along with “crop rotation effect” was the key reason for the disease suppressive activity. Key words: Agro-climatic zones, Crop rotation, FDA hydrolysis, Rhizosphere, S. rolfsii, Suppressive soil

Prevalence of potentially disease producing Escherichia coli in ducks of organized farms/ backyards and their associated environments in different agro-climatic zones of West Bengal

Prevalence of potentially disease producing Escherichia coli in ducks of organized farms/ backyards and their associated environments in different agro-climatic zones of West Bengal

Trombay Bidhan Mustard-204 (TBM-204): A high yielding yellow seed coat mustard [Brassica juncea (L.) Czern. & Coss.] variety notified for West Bengal

TrombayBidhanMustard-204 (TBM-204) has been notified throughCentral varietyrelease committee (CVRC) for cultivation in the state of West Bengal [S.O.No. 3220 (E) 5 th September, 2019]. The variety recorded a significant increase of 23% over the national check, Kranti (1213 kg/ha) in initial varietal trial (IVT) under timely sown rainfed conditions of Zone-V during rabi 2016-17. Further, the variety demonstrated a potential average seed yield of 1336 kg/ha compared to national check Kranti (1211 kg/ha), zonal check Pusa Bold (1159 kg/ha) and local check B-9 (948 kg/ha) in multi-location yield trial conducted at different agroclimatic zones of West Bengal over 4 years. TBM-204 is tolerant to insect pest aphids and diseases like Alternaria blight and white rust under field conditions. The variety, TBM-204 with yellow seed coat and high oil content (41%) is also preferred by the farmers because it does not lodge or shatter at maturity. The variety with higher seed yield and B:C ratio over B-9 in field demonstration is proposed as an alternative to B-9. Molecular marker analysis depicted distinct SSR alleles for TBM-204 compared to Kranti and Pusa Bold.

Diversity and host specialization of Tarsonemini mites (Acari, Tarsonemidae)—Investigations in the agroclimatic zones of West Bengal, Eastern India

Diversity and host specialization of Tarsonemini mites (Acari, Tarsonemidae)—Investigations in the agroclimatic zones of West Bengal, Eastern India

Diversity and abundance of insect pests in stored rice under two agro-climatic zones of West Bengal and Tripura

Diversity and abundance of insect pests in stored rice under two agro-climatic zones of West Bengal and Tripura

Antimicrobial Resistance Pattern, Clustering Mechanisms and Correlation Matrix of Drug-Resistant Escherichia coli in Black Bengal Goats in West Bengal, India.

A cross-sectional study covering four agro-climatic zones of West Bengal, India, was carried out to understand the risk-factors, antimicrobial resistance mechanism and clustering of the resistance characteristics of Escherichia coli isolated from healthy (170) and diarrhoeic (74) goats reared under intensive (52) and semi-intensive (192) farming practices. Of the 488 E. coli isolates, the majority, including the extended spectrum (n: 64, 13.11%) and AmpC β-lactamase (ACBL) (n: 86, 17.62%) producers, were resistant to tetracycline (25.2%), followed by enrofloxacin (24.5%), cefotaxime (21.5%) and amikacin (20.5%). Statistical modelling revealed that the isolates from diarrhoeic animals (p < 0.001) are likely to be more ACBL-positive than those from the healthy counterparts. Similarly, cefotaxime (p < 0.05) and enrofloxacin-resistance (p < 0.01) were significantly higher in diarrhoeic goats and in goats reared intensively. The isolates (n = 35) resistant to multiple drugs revealed the presence of β-lactamase [blaCTXM-1-(21), blaSHV-(7), blaTEM-(3), blaCMY-6-(1), blaCITM-(3)]; quinolone [qnrB-(10), qnrS-(7), aac(6’)-Ib-cr-(3)]; tetracycline [tetA-(19), tetB-(4)] and sulphonamide resistance determinants [sul1-(4)]; multiple plasmids, especially those belonging to the IncF and IncI1 replicon types; and active acrAB efflux pumps. Further, two isolates harbored the carbapenem resistance (blaNDM-5) gene and eight were strong biofilm producers. This first ever study conducted to unravel the status of AMR in goat farming reveals that not only the intensive farming practices but also certain clinical ailments such as diarrhoea can increase the shedding of the drug-resistant isolate. The emergence of multi-drug resistant (MDR) E. coli in goats, particularly those that are carbapenem resistant, is a cause for concern that indicates the spread of such pathogens even in the livestock sub-sector generally considered as naive.

The effect of photovoltaic energy penetration on a Photovoltaic-Biomass-Lithium-ion off-grid system and system optimization for the agro-climatic zones of West Bengal

The standalone Photovoltaic-Biomass-Li-ion Battery hybrid renewable energy system (HRES) is designed for the six agro-climatic zones of West Bengal, India’s largest rice-producing state. The solar radiation received in West Bengal ranges from 4 to 5.25 kWh/m2/day. The economic optimum solutions for the selected sites in the agro-climatic zones of West Bengal are designed using optimization approaches for an electrical load of 62.05 kWh/day and 13.53 kW peak for a constant biomass supply of 0.5 tonnes per day. The impact of the PV energy penetration in terms of the HRES’ battery capacity, the Net Present Cost, the Cost of Energy (COE), and CO2 emitted is explored. The optimization of the HRES is done for no unmet load and no capacity shortage with a minimum COE. The study reports a range of PV capacity for zero unmet loads and zero capacity shortage with COE in the range of 0.101–0.105 $/kWh for the sites. The HRES sensitivity analysis and comparison with the existing literature are also studied. Farmers, legislators, and the agricultural society would profit from this research, which might help West Bengal become self-sufficient and less reliant on grid electricity.

Complementary description of three species of Steneotarsonemus (Acari: Tarsonemidae) from rice agroecosystems of Eastern India with notes on their taxonomic status, spatial distribution, intraspecific variation and species composition.

Rice agroecosystems are inhabited by a number of Steneotarsonemus species worldwide with various host plant relationships and taxonomic identities. To clarify this situation, a large-scale survey was initiated in rice growing belts of eastern India and this revealed the presence of four species of Steneotarsonemus viz. S. furcatus, S. konoi, S. spinki and S. subfurcatus. However, only S. spinki and S. subfurcatus were found infesting rice while the other species were found associated with a number of graminaceous weeds. We found three intraspecific variants within the population of S. spinki which are differentially distributed in nine separate locations covering four states across eastern India. A new subgenus Linzhangia is proposed for inclusion of exceptionally unique S. subfurcatus possessing setaceous v2 on prodorsum of female. Additionally, the population of S. spinki and S. subfurcatus were found to be differentially distributed across five different agroclimatic zones of West Bengal with S. spinki being the dominant species.

Study on diversity and community structure of mite fauna associated with vegetable crops in West Bengal, India

Aim: Methodology: Results: Interpretation: A study was carried out to understand the diversity and community structures of phytoseiid and phytophagous mite fauna associated with vegetable crops in West Bengal aiming for the development of better and ecologically sound mite pest management strategy. Mite samples were collected from different agro-climatic zones of West Bengal and the specimens were brought to the AINP on Agricultural Acarology laboratory, BCKV, Kalyani for mounting on glass slides using modified o Berlese’s medium. The slides were then kept on slide wormer at 35-40 C for 5-7 days to process for observation under a phase contrast microscope. A total of fifteen species of phytoseiid mites were recorded belonging to the genera Amblyseius, Euseius, Paraphytoseius, Typhlodromips, Scapulaseius, Neoseiulus, Phytoseius, Typhlodromus (Anthoseius) and Indoseiulus. Amblyseius largoensis was observed as predominant mite species followed by Typhlodromips syzygii occupied 19.71 and 15.05 % of total predatory mite population, respectively. The other predatory mites belonging to the family Tydeidae, Bdellidae, Ascidae, Cunaxidae, Cheyletidae and Stigmaeidae were also recorded during the period of investigation. Predatory mites were observed to predate upon different stages of phytophagous mites, mealy bugs and pupae of whitefly. Concerning the phytophagous mites, Tetranychus urticae, Tetranychus ludeni, Schizotetranychus baltazari, Eutetranychus orientalis, Oligonychus andropogoni, Polyphagotarsonemus latus and Brevipalpus phoenicis were found as destructive mite pests in vegetables. Phytophagous mite is a serious concern for successful vegetables cultivation in West Bengal. Predatory mites were found effective against phytophagous mites and other soft bodied insect and they could be utilized for biological control programme to minimize the use of chemical pesticides.

Policy perspectives on agricultural water management and associated technologies suitable for different agro-climatic zones of West Bengal, India

Policy perspectives on agricultural water management and associated technologies suitable for different agro-climatic zones of West Bengal, India

Studies on reproduction and genetic parameters of Black Bengal goat (Capra hircus bengalensis) at farmers’ field under different agro-climatic zones of West Bengal

The present investigation was conducted on Black Bengal goat maintained in different agro-climatic clusters of West Bengal. Information from 10,348 kids born from 3,138 Black Bengal does during the period April 2010 to March 2019 reared at farmers' fields, was used to study the effect of non-genetic and genetic factors on reproduction traits. Age at first service (AFS) and age at first kidding (AFK) from 1,175 does; service period (SP) and kidding interval (KI) and litter size (LI) were considered for this study. Agro-climatic clusters, year of kidding and season of kidding were included as non-genetic factors whereas; parity of doe was taken as a genetic factor. The mean AFS and AFK were recorded to be 239.86±0.72 and 400.60±2.33 days respectively. The average SP was reported as 88.32±0.93 days, the average KI was 235.48±0.91 days and overall litter size/ kidding were 1.84±0.01 kids. Effect of cluster, season, parity and year of kidding had a significant effect on the reproduction traits. The heritability figures were 0.177±0.125, 0.147±0.118, 0.043±0.106, 0.176±0.091 and 0.182±0.138 for AFS, AFK, KI, SP and LS respectively. Low genetic and phenotypic correlations between KI and LS were observed. The does reared under the Murshidabad and Jhargram clusters showed better reproductive efficiencies than that of other clusters. Low heritability estimates obtained for all reproductive traits in the current study suggested that emphasis should be geared towards improving management practices to combat kid mortality and reduce the kidding intervals.

Soil organic matter prediction using smartphone-captured digital images: Use of reflectance image and image perturbation

This study evaluated a novel smartphone-based soil image segmentation technique and subsequent machine learning (ML) optimization methodology with a set of soil images for rapidly predicting soil organic matter (SOM) with minimal soil processing. A smartphone and a custom-made box were used to capture images for 90 soil samples, collected from three different agroclimatic zones of West Bengal, India under three different illumination conditions. To offset the impact of variable illumination, the reflectance component of the image was recovered by removing the illumination from the image. Further, to deceive the ML model without distorting the soil image, an adversarial image was generated by adding Gaussian noise to the image. A Tree-based Pipeline Optimisation Tool was used to find an optimum ML stacking scheme using six different ML models. Model validation statistics indicated that reflectance image-extracted sub-colour space could predict SOM with reasonable accuracy (R 2 = 0.88, RMSE = 0.28%) using original images in stack one. Moreover, the sub-colour space using perturbed images in stack one could sense noise, worsening the model validation (R 2 = 0.79, RMSE = 0.36%). Conversely, seven out of eight tested colour spaces in stack two were unable to sense the image noise, producing higher validation performance than the original images. The proposed smartphone-based image acquisition setup combined with the computer vision and ML pipeline produced an important advance in affordable optical tool-based SOM prediction with significant time and cost savings. More research is warranted to extend this approach by incorporating field images of variable soil types taken under variable illuminations. • Smartphone captured soil images were used to predict SOM. • The image reflectance was recovered to remove variable illumination. • Adversarial images were generated by adding Gaussian noise to the original images. • SOM prediction model produced good validation accuracy using original images. • Inclusion of perturbed images was able to detect noise.

Short-Term Carbon Sequestration and Changes of Soil Organic Carbon Pools in Rice under Integrated Nutrient Management in India

While the capability of integrated nutrient management (INM) in rice systems has been adequately studied, little is known about the related short-term carbon sequestration and changes in soil carbon fractions. Our study examined the responses of organic carbon pools, carbon sequestration and rice yields after application of different organic manures combined with chemical fertilizers in a rice–rice (Oryza sativa L.) cropping system in the red and laterite agro-climatic zones of West Bengal, India. The treatments included non-fertilized control; rice straw (RS) + nitrogen, phosphorus and potassium fertilizer (NPK); Gliricidia (GL) + NPK; farmyard manure (FYM) + NPK; vermicompost (VC) + NPK; and NPK only. Rice straw + NPK treatment resulted in the highest total organic carbon and passive pool of carbon. Vermicompost + NPK treatment resulted in the highest oxidizable organic carbon (0.69%), dissolved organic carbon (0.007%) and microbial biomass carbon (0.01%), followed by FYM + NPK, GL + NPK and RS + NPK as compared to control. Rice straw + NPK sequestered the highest amount of carbon dioxide (CO2) as the total organic carbon (91.10 t ha−1) and passive pool of carbon (85.64 t ha−1), whereas VC + NPK resulted in the highest amount of CO2 (10.24 t ha−1) being sequestered as the active pool of carbon, followed by FYM + NPK (8.33 t ha−1) and GL + NPK (7.22 t ha−1). The application of both NPK only and VC + NPK treatments resulted in the highest grain yields over the three cropping seasons. In spite of high carbon sequestration being observed in more recalcitrant carbon pools, RS + NPK resulted in little increase (3.52 t ha−1) in rice yield over the short term. The results of this study suggest that the short-term changes of soil carbon fractions and carbon sequestration primarily depend on the type of organic manure used. Vermicompost, FYM and GL provide more labile carbon, which can improve rice yield over the short term. However, it is suggested to explore the dynamics of different carbon fractions, carbon sequestration in different pools and rice yields over longer periods of time.

Spatial Distribution of Sulphur and its Relationship with Soil Attributes under Diverse Agro-climatic Zones of West Bengal, India

This investigation is aimed to conduct a delineation study to know the spatial distribution of available sulphur (S) in different agro-climatic zones and their influencing soil factors. Geographical information system (GIS) is an important tool to identify the S deficient sites. In this study, Arc Info GIS has been used to prepare the spatial distribution maps of available S in the soil of different districts. For this, grid-based detailed block-wise soil sampling has been carried out during 2017–2019 in long-term crop-growing fields from ten (Darjeeling, Alipurduar, South Dinajpur, Malda, Murshidabad, Nadia, Bankura, Purulia, Birbhum and East Midnapore) districts of West Bengal, India, belonging to six different agro-climatic zones. Spatial distribution maps (1:50000) show that available S highly varies from one agro-climatic zone to another zone. The results showed that available S content was highest in the terai zone (20.28 ± 8.00 mg kg−1) followed by the northern hill zone (11.09 ± 5.54 mg kg−1) and old alluvial zone (10.39 ± 6.8 mg kg−1). The lower available S was found in areas under the red and laterite zone (6.47 ± 4.29 mg kg−1). This study concluded that available S status is low to deficient for red and laterite and coastal saline zones, which differs from hill and terai zone. Organic carbon content and silt content exerted a positive correlation (r = 0.79 and 0.78, respectively) with available S.

Milk from healthy or infected cattle as a source of multi-drug resistant, AmpC β-lactamase-producing Escherichia coli

Drinking raw unpasteurized milk or products made from raw milk is a recent trend observed among the people due to their belief in enhancing nutritional properties and better taste. It poses a great risk of microbial transmission along with antibiotic resistance gene pool (extended spectrum beta-lactamase or ampC) among the consumers. The study was conducted to detect the occurrence of AmpC producing E. coli in raw milk samples collected from healthy and mastitic cattle in West Bengal. In total, 450 cow milk samples were collected from all the six agro-climatic zones of West Bengal. The samples were collected from healthy as well as infected cattle suffering with clinical or sub-clinical mastitis, irrespective of age and breed. The collected milk samples were tested with MAST INDEX reagent for the detection of sub-clinical mastitis. E. coli isolates obtained from cattle milk samples (n=450) were subjected to cefoxitin-cloxacillin double disc synergy test and PCR based confirmation of blaAmpC, class I integron and CITM genes. All the ACBL producing E. coli isolates were subjected for their resistance to other antimicrobials. All the levofloxacin and Co-Trimoxazole resistant ACBL-producing isolates were studied for PMQR, sul1, sul2, sul3 genes. E. coli was isolated from 205 collected milk samples (205/450, 45.6%). The phenotypical test detected 231/383 isolates (60.3%) were AMPC producers which were also found to possess blaAmpC. Comparison of ACBL-producing E. coli occurrence in cattle with mastitis, sub-clinical mastitis and healthy cattle revealed significantly higher occurrence rate in infected cattle than the healthy ones (p<0.05). Phenotypical antibiotic resistance pattern of the isolates showed resistance against penicillin-G (100%), cefoxitin (100%), ampicillin (42%), co-trimoxazole (13.5%) and levofloxacin (5.2%). Out of 30 co-trimoxazole resistant isolates identified, 25 (83%) and seven (30.4%) isolates possessed sul1 and sul2 gene, respectively, whereas, four (13.3%) isolates possessed both sul1 and sul2 genes. Three levofloxacin resistant isolates possessed qnrS gene. This is the first systemic study with substantial numbers of milk samples from healthy and infected cattle depicting occurrence of ACBL-producing E. coli and linkage present in the isolates between the genes encoding ACBL and quinolone or sulphonamide resistance.

Genetic diversity characterization of Wood apple (Feronia sps.) for identification of superior genotypes

Wood apple fruit is a hard shelled many seeded berry with its pinkish brown aromatic sour – sweet pulp being the edible portion. Total eleven (11) numbers of wood apple plants were stratified from different agroclimatic zones of West Bengal depending on availability of fruit crop and convenience of the study at Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia, West Bengal during the years 2013-2015. Under the observation for characterization, the plant physical parameters has been analyzed with the help of Biodiversity International Tropical Fruit Descriptor (NBPGR) and so for preliminary evaluation, fruit physical parameters and fruit biochemical parameters has been analyzed. During the course of survey the tree age of wood apple varied from 15yrs to above 40yrs in age at different germplasm in which the height and trunk girth varied from 10m to above 20m and 88.2 cm to 157.4 cm. Branching pattern and crown shape was observed to be irregular in all the accessions whereas, tree growth habit varied from erect to spreading type. Leaf characters in wood apple reveals obovate leaf blade shape, obtuse to retuse leaf apex, cuneate leaf base, odd pinnate leaf orientation and pinnate leaf venation. Length of the leaf blade ranges from 3.05 cm to 4.12 cm and breadth varies from 1.06 cm to 3.08 cm. Maximum fruit length was recorded in ACC-8 (8.04 cm) and breadth of 7.96 cm in ACC-6. Maximum fruit weight (306.02 g), peel weight (73.68 g) and number of seeds (28.42) was from the ACC-4. Maximum total sugar 28.57 mg/100 gm pulp (ACC-1), reducing sugar 13.88 mg/100 gm (ACC-4), acidity 1.77 mg/100 gm (ACC-5) and Vit. C 102.04 mg/100 gm (ACC-2) has been recorded. Average linkage technique clustering when applied on squared Euclidean distance matrix a total of 6 clusters were formed for plant physical parameters, a total of 7 clusters were formed for fruit physical parameters and a total of 6 clusters were formed for fruit biochemical parameters.

Diversity analysis of selected rice landraces from West Bengal and their linked molecular markers for salinity tolerance.

Study of genetic diversity in crop plants is essential for the selection of appropriate germplasm for crop improvement. As salinity posses a serious environmental challenge to rice production globally and especially in India, it is imperative that the study of large collections of germplasms be undertaken to search for salt tolerant stocks. In the present study, 64 indica germplasms were collected from different agro-climatic zones of West Bengal, India, from the Himalayan foothills in the northern part down to the southern saline belt of the state keeping in view the soil characteristics and other edaphic factors prevailing in the region. Salt tolerance parameters were used to screen the large set of germplasms in terms of root-shoot length, fresh-dry weight, chlorophyll content, Na+/K+ ratio and germination potential in presence of salt. Standard evaluation score or SES was calculated to find out tolerant to sensitive cultivar. Twenty-one SSR markers, some associated with the Saltol QTL and others being candidate gene based SSR (cgSSR) were used to study the polymorphism of collected germplasm. A wide diversity was detected among the collected germplasms at the phenotypic as well as molecular level. Of the 21 SSR markers, 15 markers were found to be polymorphic with 88 alleles. Based on phenotypic and biochemical results, 21 genotypes were identified as salinity tolerant, whereas 40 genotypes turned out to be salt susceptible. The present study shows that apart from the established salt tolerant lines, several other landraces like Bonkanta, Morisal, Ghiosh, Patni may be the source of salt tolerant donor in future breeding programs.

Characterization of methicillin-resistant and enterotoxins producing Staphylococcus aureus in bovine milk in India

The present study was conducted to detect the occurrence of methicillin-resistant and enterotoxin producing Staphylococcus aureus in bovine milk with SCCmec, spa type, antimicrobial sensitivity and MIC of anti-staphylococcal drugs against the isolates. A total of 450 composite milk samples both from cattle with or without mastitis were collected from all agro-climatic zones of West Bengal. Nine (9.6%) S. aureus isolates were phenotypically detected as MRSA and all of them possessed mecA. Whereas, 12 (12.8%) and 4 (4.3%) isolates possessed the staphylococcal enterotoxins sei and seg, respectively. Six and three isolates belonged to SCCmec type Iva and type V, respectively. Spa typing of the isolates showed MRSA isolates belonged to t304 and t6297. All the MRSA isolates were multidrug resistant. The MIC of oxacillin, vancomycin, ampicillin, ciprofloxacin and linezolid against MRSA isolates was 8->256 μg ml−1, 0.064–0.256 μg ml−1, 0.38–2 μg ml−1 and 6–8 μg ml−1, and 0.1 μg ml−1, respectively. The finding is worrying from public health point of view due to detection of MRSA and enterotoxin (seg,sei) producing S. aureus in milk samples which are commonly associated with human infection or food poisoning cases. This is the first comprehensive study with substantial numbers of samples for characterization of MRSA in bovine milk in India.

Field screening of different genotypes of bitter gourd for infestation with the melon fruit fly, Bactrocera cucurbitae (Coquillett) in two agro-climatic zones of West Bengal, India

Bitter gourd (Momordica charantia L.) also known as bitter melon being rich in folate and vitamin C is one of the most popular cucurbitaceous vegetables grown extensively in the tropics and subtropics especially in India. Besides its numerous culinary preparations, it has immense medicinal properties as well as ornamental uses. The fast growing vines and creepers of bitter gourd attract a number of insect pests of which fruit fly (Bactrocera cucurbitae Coq.) is the most destructive due to difficulties associated with its chemical control as the maggots remain and feed inside the fruits, protected from direct contact with insecticides. Therefore, exploration of alternative control measures for this pest is crucial and identification of promising resistance genotypes could be the effective option. Considering the above aspects in view, twenty five genotypes of bitter gourd (M. charantia L.) were preliminary screened under field condition to study their susceptibility against the infestation of melon fruit fly, B. cucurbitae (Coq.) in two agro-climatic zones of West Bengal, India. Based on the performance of preliminary screening, nine genotypes were selected for final screening. The experiment on preliminary screening was conducted at Kalyani, Nadia (Gangetic Alluvial zone) and Sekhampur, Birbhum (Red and Laterite zone) during spring-summer season of 2016 and 2017 while the final screening was done in 2018. Results of the study revealed that percent fruit infestation and larval density per fruit varied significantly in all the tested genotypes and none of the genotypes were free of infestation with B. cucurbitae. During preliminary screening, the pooled data of mean percent fruit infestation of two years at two locations showed that infestation of melon fruit fly was significantly lower in the genotype US-6214 (14.50%) with larval density of 3.63 larvae per fruit followed by Meghnad-2 (16.50% and 4.08 larvae per fruit). Highest mean percent fruit infestation was recorded in the genotype Pusa Do Mausami (69.67%) with larval density of 10.77 larvae per fruit followed by Diamond Bolder (60.67% and 8.13 larvae per fruit) and were categorized as susceptible. Out of the twenty five genotypes of bitter gourd tested, six genotypes were classified as resistant, eleven genotypes as moderately resistant and eight genotypes as susceptible against melon fruit fly infestation. The mean data of the final screening at two locations revealed that US-6214 and Meghnad-2 recorded significantly low percent fruit infestation (14.35% and 16.33%) with 3.85 and 4.37 larvae per fruit while Pusa Do Mausami had the highest infestation and larval density (63.67% and 10.36 larvae per fruit). These findings suggest that US-6214 and Meghnad-2 may be utilized in resistance breeding programmes against melon fruit fly.

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