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Open Access
Biosystematic studies on Thyridid moths (Lepidoptera: Thyrididae) in India
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-09) Samraj, J.M.; Agnihotri, Meena
Open Access
Studies on effect of neonicotinoids on colony development of Apis mellifera L. and foraging behavior of honey bee species in mustard crop
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-03) Ravindra Kumar; Mall, Pramod
Studies on effect of imidacloprid 70 WS seed treatment and thiamethoxam 25 WG spray at pre-bloom and 10% bloom on colony development of Apis mellifera L. and foraging behavior of honey bee species in mustard crop were carried out at Govind Ballabh Pant University of Agriculture and Technology Pantnagar, Udham Singh Nagar, Uttarakhand during 2018 and 2019. The experiment was conducted in both semi and open field conditions. Observations were recorded regarding effect of imidacloprid seed treatment, thiamethoxam spray at pre-bloom and 10% bloom on colony development, foraging behavior, mortality and yield parameters of Indian mustard. The risk to honey bee colonies in the field was investigated by exposing the colonies to imidacloprid seed treatment and thiamethoxam treated mustard crop at rates recommended for insect control. Detailed examination of colony development throughout the period of exposure demonstrated that under open and semi-open field condition thiamethoxam spray at 10% bloom had a negative impact on brood, pollen, nectar, honey capped and egg cell area under open and semi-open field condition. Foraging activity and foraging rate was found to be significantly less in thiamethoxam spray at 10% bloom in comparison to thiamethoxam spray at pre-bloom, imidacloprid seed treatment and control. Mortality of adults of Apis mellifera L. was significantly higher in thiamethoxam spray at 10% bloom in comparison to thiamethoxam spray at pre-bloom, imidacloprid seed treatment and control under open and semi-open field condition. Mustard yield was found to be highest in imidacloprid seed treatment followed by thiamethoxam spray at 10% bloom, pre-bloom and control under open and semi-open field condition.
Open Access
Pollination biology in oilseed Brassica and foraging behavior of pollinators in intercropping ecosystem
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-10) Sajwan, Rahul; Khan, M.S.
The present study was conducted to determine the effect of flower biology and phenology of oilseed Brassica on the foraging behavior of pollinators and the effect of intercropping (fennel, coriander and chickpea) on the abundance of pollinators in seven species of oilseed Brassica at Norman E. Borlaug Crop Research Centre in GovindBallabh Pant University of Agriculture and Technology, Pantnagar (Uttarakhand) during the rabi season 2020-21. In different Brassica species, length of petal and width ranged from 7.82-13.79mm to 3.33-7.92mm, while style and sepal length ranged from 4.55-9.57mm and 3.85-7.82mm. Various Brassica species completed 50% flowering stage in 53-118 days after sowing and the flower longevity lasted from 3-8 days during different blooming time. Anther dehiscence started at 7.00hr and maximum flowers were opened up until 10.00hr. Flower of various Brassica species showed introse and extrose positions of anthers respectively during the day hours. Pollen and ovule size ranged from 21.65 - 31.81μm and 297.51-413.22 μm respectively, and number of pollen grains varied from 5500-17000 and ovules 7-38 in different oilseed Brassica species. Stigma receptivity was maximum between 11.00-13.00hr. On the basis of flower phenological study B. napus var. GSC-6, B.alba and B. carianata were considered showing superior characters among eight oilseed Brassica varieties. The population of insect visitors was higher in oilseed Brassica experiment as compared to intercropping experiment. A total of 28 insects belonging to 13 families under 5 orders were found to visit the different oilseed Brassica bloom. In intercropping ecosystem, 22 species belonging to 11 families under 5 orders were recorded. Order Hymenoptera contributed higher percentage of the insect visitors. Major flower visitors of oilseed Brassica were Apismellifera, A. cerana, A dorsata, A. florea and Halictus species. Halictus species was dominant visitor of B. nigra while A. mellifera was dominant visitor of all other Brassica species followed by A. cerana. However, among Brassica species A. mellifera and A. florea were most abundant pollinators in B. carinata while A.cerana and A. dorsata were most abundant pollinators in B. campestris var. BSH-1 and B.napus var. GSC-6, respectively. The studies on varietal preference of oilseed Brassica to bee pollinators indicated that B. nigra was most preferred by bees followed by B. carinata, B. napus var. GSC-6, B.juncea var. PM-31 and B. campestris var. BSH-1. Foraging rate of Apis species on different cultivars revealed that A. mellifera had highest foraging rate (11.27 flowers/min) followed by A.cerana (8.47 flowers/min) and lowest of A. dorsata (4.15 flowers/min) and bee species indicated highest foraging rate on B. napus var. GSC-6 (11.48 flowers/min) followed by B. alba (10.10 flowers/min) and B. nigra(8.88 flowers/min). The observations on foraging speed revealed that time spent byApis species was maximum on cultivars of B.juncea var. PM-31(4.23 sec/flower) followed by B. campestrisvar. BSH-1 (3.95 sec/flower) and B. napus var. GSC-6 (3.52 sec/flower). Among the Apisspecies, A. mellifera spent maximum time (3.92 sec/flower) on flower followed by A. cerana(3.79 sec/flower), A. florea (3.20 sec/flower) and minimum time spent by A. dorsata (1.9 sec/flower). Pollinator activity was maximum between 10.00-12.00 hr. Apisflorea carried significantly higher loose pollen load (31371 pollen grains) followed by A. mellifera (26171 pollen grains), A.cerana (17142 pollen grains), Halictus species (12800 pollen grains) and A.dorsata (5371 pollen grains) and maximum amount of pollen was collected by Apis species from B.juncea var. Varuna (28000 pollen grains) and B. nigra(27280 pollen grains). Apismellifera was the most efficient pollinator in different oilseed Brassica with pollination efficiency index (743.25) followed by A. florea(323.12), A.cerana (221.14), Halictus species (147.20) and A. dorsata (24.70). Mustard intercropping with coriander had a positive effect on increasing the diversity of insect visitors rather than increasing the abundance ofApis species. The blooming phases of mustard intercropped with fennel and chickpea were not synchronized, therefore, fennel and chickpea as intercrop had no effect on pollinator’s abundance. The abundance of bee pollinators on oilseed Brassica flowers was positively influenced by high temperature, sunlight hours, and wind velocity, whereas the number of bee pollinators was negatively influenced by low temperature and relative humidity. Size of flower characters of oilseed Brassica species had positive influence on abundance of A. mellifera and A.dorsata, whereas A. florea and Halictus species showed negative correlation with size of flower characters.
Open Access
Screening of germplasms and population dynamics of major insect pests of spring green gram Vigna radiata (Linn.)
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-09) Tamta, Arnima; Gaur, Neeta
The present investigation was conducted during Spring season of 2021-22 at Norman. E. Borlaug. Crop Research Centre of G.B. Pant University of Agriculture and Technology, Pantnagar (Uttarakhand) and Morphology laboratory of Department of Entomology with the objectives screening of germplasms of green gram in field as well as laboratory conditions, occurence major insect pests in field conditions. Major insect pests observed in green gram during spring season were whitefly, Bemisia tabaci (Gennadius), thrips, Megalurothrips distalis (L.), jassids Empoasca kerri (Pruthi) and tur pod bug Clavigralla gibbosa (L.). The population dynamics indicated that incidence of Bemisia tabaci and Empoasca kerri were recorded during the vegetative stage and attained their peak population at 17th SMW, while infestation of Megalurothrips distalis was recorded during flowering stage attaining the peak at 19th SMW and highest population of Clavigralla gibbosa was seen during pod formation stage reaching peak insect population at 19th SMW. Correlation studies indicated that max and min temperature, max RH and sunshine hours showed significant positive correlation with whitefly population whereas, thrips population showed significant positive correlation with max temperature, min temperature and max RH. Jassid population showed significant positive correlation with max temperature, min RH. In regression analysis coefficient of determination varied from 0.96 to 0.99 and the percent eigen values of principle component 1 was 4.76 whereas eigen values of principle component 2 was 1.27. Screening of seventy green gram germplasms under field conditions indicated that twenty germplasms were found promising having lower mean population of insect pest. Among the twenty germplasms four (SSME 21-70, SSME 21-55, SSME 21-47, SSME 21-41) showed less preference to S. litura as compared to check PM-05. The four less preferred germplasms were checked to see the effect of trichome density and length on tobacco caterpillar feeding. It was seen that length and density of trichomes varied significantly among the germplasms and proved that the most tolerant germplasm (SSME 21-70) having more trichome density (215.6e) followed by SSME 21-55 (194.6d) as compared to PM-05 (118.3 a) whereas, maximum length of trichomes were seen in SSME 21-70 (1357d) followed by SSME 21-55 (1186.3c) as compared to PM-05 (918a) which indicated that higher trichome length and density contributed to less preference to insect feeding.
Open Access
Compatibility of Bacillus thuringiensis (Berliner) with insecticides against Helicoverpa armigera (Hübner) infesting chickpea
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-09) Shashikala, M.; Gaur, Neeta
Chickpea (Cicer arietinum L.) is one of the major rabi pulse consumed and cultivated in the world. Chickpea severely suffers from infestation of Gram pod borer (Helicoverpa armigera) in all the cultivated areas of the world including India. It has been recorded 56 to100 per cent yield loss due to infestation of chickpea pod borer. The continuous prevalence of this pest makes its management most important during chickpea cultivation. In the present investigation efforts were made to study the compatibility between Bacillus thuringiensis, entomopathogenic bacterium and insecticides at different lethal and sublethal concentrations (R, R/2, R/4, R/8 and R/16) under in-vitro conditions. Further field efficacy of Bt, insecticides and different combinations were evaluated against H. armigera infesting chickpea. Incremental Cost benefit ratio(ICBR) was also calculated. Compatibility study showed that as the concentration of the insecticides increased bacterial growth decreased indicating reduced compatibility over increased concentration. Bt was significantly highly compatible (compatibility index 1) with chlorantraniliprole 18.5 SC at all the tested concentrations as compared to other treatments. Maximum per cent inhibition was observed at recommended dose (46 ppm) of chlorantraniliprole 18.5 SC (21.663) followed by emamectin benzoate 5 SG which showed compatibility index 2 with 27.401 per cent inhibition. However, lambda cyhalothrin 5 EC, ethion 50 EC and neem 10000 ppm were found non compatible with Bt at all the concentrations with compatibility index 3. In field efficacy combination of Bt with insecticides was found more effective as compared Bt or insecticides alone against gram pod borer. Among different combinations Bt + half dose of chlorantraniliprole 18.5 SC with significantly minimum larval population was recorded (0.20) with per cent reduction (93.11) followed by Bt + emamectin benzoate 5 SG while minimum was in Bt alone against H. armigera infesting Chickpea. The incremental cost benefit ratio (ICBR) was calculated on the basis of grain yield obtained. The net returns in treatment Bt + chlorantraniliprole was found higher followed by chlorantraniliprole alone among all the treatments. Maximum B:C ratio was in Bt + chlorantraniliprole (1.65:1) followed by chlorantraniliprole alone and Bt + emamectin benzoate while minimum was in neem alone as compared to control (0.66). The present investigation revealed that combination of Bt + half dose of chlorantraniliprole 18.5 SC was significantly effective against gram pod borer. A need based integrated strategy can be formulated by use of this combination for the management of chickpea pod borer.
Open Access
Biological and phylogenetical studies of whiteflies from north-western Himalayan region
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-03) Patel, Chenesh; Srivastava, R.M.
An integrated approach was carried out to explore the diversity of reproductive host plant, along with the seasonal incidence, host preference and biotic potential, taxonomic identification using molecular and morphological tools and use of essential oils for the management of whiteflies in Uttarakhand Himalayan region. Extensive surveys were conducted in 45 locations of 4 district of Uttarakhand during 2017-2019 to record the potential reproductive host associated with Bemisia tabaci and Trialeurodes vaporariorum and total 118 host plant species belonging to 49 families were documented. Host plants belonging to family Asteraceae, Fabaceae, Solanaceae, Cucurbitaceae, were found as most preferred host plant by both B. tabaci and T. vaporariorum. Whitefly (B. tabaci) was present on brinjal and tomato throughout the cropping season at Vegetable Research Centre, Pantnagar during 2017-2019 and its peak activity was observed on last week of December in both the crops. Whitefly population had significantly negative correlation with maximum temperature (r= -0.50** and r= -0.53**), minimum temperature (r= -0.61** and r= -0.57**) and evaporation (r= -0.64** and r= -0.66**) while non significant correlation was observed with sunshine hours in both the years on tomato and brinjal plants. The feeding and oviposition preference and biotic potential studies proved that among all brinjal was the most preferred host for feeding and oviposition followed by tomato and cabbage for B. tabaci and T. vaporariorum while the least preferred host recorded was bottle gourd and chilli for B. tabaci and T. vaporariorum respectively. Similarly, the preimaginal developmental period of immature stages of B. tabaci and T. vaporariorum was faster on brinjal (19.40 days and 21.57 days) than on tomato (22.40 days and 24.03 days). The survival rate was also maximum in brinjal plants for both the species as compared to tomato. The comparative morphological studies of life stages of B. tabaci and T. vaporariorum showed distinct differences in morphological features such as the no. of marginal setae, vasiform orifice, ligula, antennae and eyes. Morphological and morphometric features of both whitefly species were imaged and illustrated in detail for correct field level identification. The molecular diversity of B. tabaci and T. vaporariorum using mt COI markers followed by sequencing revealed the preponderance of genetic diversity in whitefly species. In case of B. tabaci, five different types of biotypes were found i.e., Asia II-1, Asia I, Asia II-5, MEAM 1 and Uganda. In case of T. vaporariorum the obtained phylogenetic tree revealed that there was no variation in the collected samples. Various plant essential oils were tested for repellency and ovipositional deterrent effect against B. tabaci. Among all the essential oils, mint oil showed maximum repellency and ovipositional deterrence, followed by tulsi and citronella oil while, significantly low repellency and ovipositional deterrent effect was recorded in lemongrass oil
Open Access
Management of sucking insect pests complex of potato with some foliar and soil incorporated insecticides
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-09) Kunwar, Roopam; Srivastava, R.M.
The current study was carried out at Vegetable Research Centre, GBPUA&T, Pantnagar, Uttarakhand during Rabi crop season of 2020-21. Seasonal incidence of sucking insect-pests, viz., aphid, leafhopper, thrips and whitefly were observed from 46th-05th SW (3rd week of December to 1st week of February). The peak activity of M. persicae and A. gossypii (10.56 and 8.97/3 compound leaves) was observed during 51st SW while the population of whitefly, leafhopper and thrips reached at peak on 49th SW with 13.81, 5.35, and 12.40 mean counts/3 compound leaves respectively. The correlation studies indicated a negative correlation of M. persicae and A. Gossypii population with temperature (maximum) (r= -0.77** and r= -0.75**), and a positive correlation (r= 0.67* and r= 0.66*) with relative humidity (minimum). Whitefly and leafhopper population displayed a positive correlation with maximum temperature (r=0.74**and r= 0.71**), and a negative correlation with maximum (r= -0.65* and r= -0.63*) and minimum relative humidity (r= -0.69* and r= -0.64*). The thrips population exhibited a positive correlation with maximum temperature (r= 0.70*) and a negative correlation with maximum (r= -0.64*) and minimum (r= -0.63*) relative humidity. The regression analysis indicated that the studied weather factors influenced population of aphid (M. persicae, R2= 0.79, and A. gossypii, R2= 0.75), whitefly (R2= 0.77), leafhopper (R2= 0.75), and thrips (R2= 0.74) on potato with reasonable accuracy. Comparative studies of different insecticide treatment for the management of aphids revealed that treatment T6 (First spray: Imidacloprid 17.8 SL @ 0.04% + Second spray: Thiamethoxam 25 WG @ 0.05%) was the most effective insecticide combination against aphids (76.84% reduction over control) with highest yield of 30.10 t/ha and maximum benefit cost ratio (1:2.14). However, in the case of whitefly T3 (First spray: Diafenthiuron 50 WP @ 0.10% + Second spray: Thiamethoxam 25 WG @ 0.05%) was found as the most effective treatment (72.93% reduction over control) with maximum yield of 29.06 t/ha and highest benefit cost ratio of 1:2.00. Different soil incorporated insecticides evaluated against major sucking pests (whiteflies, leafhoppers and aphids), revealed that higher dose of Fipronil 0.3 G @ 25 kg ha-1 (T4) was found to be more effective and superior in reducing infestation of these pests with a high per cent reduction 79.38%, 80.98%, and 78.68% respectively over control with highest yield of 31.48 t/ha and maximum benefit cost ratio of 1:2.27 and it can be used as an alternative for Phorate 10 G.
Open Access
Studies on diversity and abundance of predatory Coccinellids in different crop ecosystems at Pantnagar
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-09) Manimala, Rayapureddi Naveena; Agnihotri, Meena
The present investigation was carried out during November, 2020 - April, 2021 at six different locations and laboratory studies were conducted at Pulse Entomology Laboratory, Department of Entomology, Govind Ballabh Pant University of Agriculture & Technology, Pantnagar. Diversity of predatory coccinellid beetles was studied in 32 crops including field crops, vegetable, fruit and ornamental crops. Eleven species of predatory coccinellid beetles were recorded. Among all the species, ten species were recorded under the subfamily coccinellinae and the one species belonged to subfamily chilocorinae. Among all these crops, maximum number (six) of species of coccinellids were observed in rose and chrysanthemum and the minimum number (one) of species were observed in chilli, cabbage, gerbera and dahlia. Seasonal abundance of coccinellid species in different crops revealed that three species C. septumpunctata, C. sexmaculata and C. transversalis were found active throughout the study period. The peak population (1.1/m2) of H. dimidiata during 7th SW, C. transversalis (7.1/m2) during 11th SW, C. septempunctata (47.5/m2) and P. dissecta (3.1/m2) during 12th SW, I. koebelei (0.4/m2) and H. variegate (0.2/m2) during 15th SW, C. sexmaculata (30.5/m2), M. discolor (4.5/m2) and M. univittata (2.6/m2) during 50th SW while B. suturalis (2.4/m2) and A. cardoni (0.2/m2) during 52th SW. Present study showed that these predatory coccinellid species were well acclimatized with all the weather conditions at pantnagar, however population of coccinellids was different in various crops and this knowledge could be helpful for the utilization of these beetles in biological control program. Olfactory response of predatory coccinellid beetles towards aphids and their host plants revealed that an increased number of coccinellid beetles were observed when host plants were added with aphids. C. septempunctata showed a higher response (30%) towards R. Maidis infested wheat, L. erysimi infested mustard and M. rosae infested rose, C. sexmaculata showed a higher response (40%) towards R. maidis infested wheat and C. transversalis showed a higher response (35%) towards M. rosae infested rose. Present study revealed that the tested crops could be utilized as trap crops aside the major crops to attract the predatory coccinellid beetles.
Open Access
Biology, behavior and ecofriendly management of greater wax moth, Galleria mellonella Linnaeus
(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2021-09) Tiwari, Jahanvi; Pandey, Renu
The present investigation on biology, behavior and eco-friendly management of Greater wax moth was conducted at Department of Entomology, GBPUA&T, Pantnagar, Uttarakhand during 2020-21. Biological study of wax moth revealed that natural diet is more suitable for rearing of wax moth as compared to artificial diet due to the shorter developmental period (57.05±0.60 days) and higher fecundity (902.65±148.74 eggs/female) of wax moth on natural diet. However, artificial diet can be used as a costeffective and easily accessible alternative to natural diet for laboratory rearing of wax moth. For studies regarding the management of wax moth, the behavioral bioassay of female wax moth using pheromone blends revealed that 7:3 (30% C11:AL) blend of aldehydes (nonanal and undecanal) elicited maximum behavioural response at 0 DAT which remained effective up to 1 DAT. The studies on effect of different colors of optical light on Greater wax moth revealed that adult moths were attracted towards the blue colored light (lower wavelength) and maximum attraction was observed at 36hrs of exposure to light. Bio-efficacy of Neem Care 0.15% EC and Dipel 3.5% ES showed 80.0% and 86.7% larval mortality respectively, at 48 HAT in dipping method @ 4.0 ml/L concentration. Thus, from the study it was concluded that pheromone blend of nonanal and undecanal in 7:3 ratio is able to elicit maximum behavioral response in female wax moths. The maximum attraction of wax moths was observed towards blue colored light. Hence, pheromone traps and light traps can be developed and incorporated as components of Integrated pest management of Greater wax moth in future. The biopesticides Dipel 3.5% ES and Neem Care 0.15% EC were able to cause significant larval mortality in wax moth at 4.0 ml/L, therefore both the formulations can used for eco-friendly management of wax moth.

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