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Bioecology and management of rice leaf folder, Cnaphalocrocis medinalis (Guenee) infesting paddy in Himachal Pradesh
(Palampur, 2017-06-27) Chhavi; Sharma, Pawan K.
The present investigation entitled “Bioecology and management of rice leaf folder, Cnaphalocrocis medinalis (Guenee) infesting paddy in Himachal Pradesh” was undertaken in the Department of Entomology, CSKHPKV, Palampur and Rice and Wheat Research Centre, Malan during 2014-2016. Under laboratory conditions, C. medinalis completed three generations from August to mid-December. The life cycle of C. medinalis consisted of four distinct stages viz., egg, larva, pupa and adult, each having an average duration ranging between 3.70-4.50, 17.50-20.50, 7.00-7.50 and 6.40-7.40 (female); 2.50-3.30 (male), respectively, during different generations. The fertility parameters worked out for first, second and third generation resulted in the net reproductive rate (R0 ) of 29.16, 17.94 and 17.72 female eggs per female with the corresponding true generation time of 37.06, 37.99 and 39.38 days, respectively. The intrinsic rate of increase (rm) was maximum in the first generation (0.091) and minimum in the third generation (0.073). The field collected adults of last generation when reared under laboratory conditions to study the survival of pest, failed to lay eggs. However, a few individuals of C. medinalis larvae survived in winter till January on paddy plants and weeds and a limited feeding was observed during this period. Survey for the incidence of C. medinalis and its associated natural enemies in four locations viz., Sundernagar, Nurpur, Jogindernagar and Palampur of Himachal Pradesh was conducted during 2015 and 2016 at different time intervals. The pest appearance was noticed in the second fortnight of July at Nurpur, Palampur and Jogindernagar. Whereas, at Sundernagar, the pest activity initiated during first fortnight of July and population of adults was at its peak in the first fortnight of September in all the four locations. From the correlation studies between adult catch and abiotic factors, it was concluded that the temperature (maximum and minimum) favours the C. medinalis build-up. However, RH (maximum and minimum) and rainfall had a negative impact on C. medinalis abundance. During survey, Cotesia cypris (Nixon) was found to be the most dominating larval parasitoid associated with C. medinalis. Fifty natural enemies were encountered in paddy ecosystem of all the four locations, out of which twenty four were found associated with C. medinalis. Spiders viz., Araneus pseudosturmii (Yin et al.), Micropholcus fauroti (Simon) and Runcinia ghorpadei (Tikader) were recorded for the first time from India. Based upon the Shannon index, diversity of natural enemies was maximum at Palampur (2.58-2.65) and minimum at Nurpur (1.52-1.89). The leaf damage and losses inflicted to paddy due to different release levels of C. medinalis viz., 2, 4, 6, 8, and 10 larvae per hill released at panicle initiation stage revealed that maximum leaf infestation was 24.48 per cent at highest release level (10 larvae/ hill) and lowest (6.94%) at release level of 2 larvae per hill and per cent avoidable losses varied from 0.94-28.93 per cent. Among forty three genotypes evaluated against C. medinalis, thirty three genotypes were found moderately resistant, nine as moderatey susceptible and one as susceptible. None of the genotypes was found to be free from leaf folder damage. Among the six treatments of Trichogramma chilonis, maximum control was achieved when 1,50,000 parasitized eggs per hectare were released. However, this treatment was found to be at par with 1,00,000 and 1,25,000 parasitized eggs per hectare. Out of six insecticides and one biopesticides evaluated against C. medinalis, flubendiamide (24 g a.i./ ha), indoxacarb (30 g a.i./ ha) and lambda-cyhalothrin (12.5 g a.i./ ha) were found to be efficacious. However, biopesticide, Bt (1.5 kg/ ha) was found to be least effective for the control of pest. Incremental output input ratio was highest in case of lamba-cyhalothrin and lowest in Bt
Open Access
BIOECOLOGY AND MANAGEMENT OF RICE HISPA, DICLADISPA ARMIGERA (OLIVER) UNDER MID-HILL CONDITIONS OF HIMACHAL PRADESH
(CSKHPKV, Palampur, 2017-04) Urvi; Srivastava, Ajai
Detailed studies on rice hispa, Dicladispa armigera (Oliver) were undertaken at CSK Himachal Pradesh Krishi Vishvidyalaya, Rice and Wheat Research Centre, Malan during 2014-2016. The studies included understanding rice hispa’s annual life cycle, its population build-up, assessment of losses inflicted and management with suitable insecticides and biopesticides. The life history of D. armigera consisted of four distinct stages viz. egg, grub, pupa and adult, each having an average duration of 4.5, 14.0, 9.1 and 22.4 (male); 38.7 (female) days, respectively. Both adults and grubs caused damage due to its feeding on paddy leaves. As many as 3-4 generations were recorded under laboratory conditions (mid June-mid November), but the adults of last generation failed to lay eggs. A few individuals of adults of last generation survived on rice seedlings and weed host, Cynodon dactylon (Linn.) till April-May with limited feeding and no egg-laying. Field observations recorded the incidence of hispa adults on wheat crop during February-April. With the early monsoon showers, the adults of hispa started appearing on weeds viz. C. dactylon, Cyperus rotundus (Linn.), Andropogon gayanus (Kunth), Digitaria sanguinalis (Linn.) and Panicum dichotomiflorum Michx., etc in the early June and thereafter it started feeding on paddy crop as soon as it was transplanted (July). During early stages of crop till 39th Standard Meteorological Week (SMW), both adult and grub incidence were recorded on paddy, which built-up during the season. Adults remained associated with the crop till its maturity. The population reached its peak during 31-39 SMW (August-September). Relative humidity significantly and positively influenced its build-up. Natural parasitization of grubs (or pupae) by a eulophid wasp, Chrysonotomyia sp. was reported. Damage and losses inflicted to paddy due to rice hispa as quantified by release density and phenological crop stage revealed that release at early stage (20-days after transplanting, DAT) inflicted more leaf damage (64.9 per cent leaf damage index, at 3-hispa release density) compared to later stages. Moreover, the regression analysis revealed that per unit increase in hispa density at early stage (20-DAT) resulted in 5.82, 5.73, 441.4 reduced number of tillers, panicles and grains, respectively, and the respective grain weight by 8.06g (per four rice hills). Also, at release stage of 40-DAT, the grain number and grain weight reduced significantly (b= 258.5 and 6.87, respectively), but at advanced release stage (60-DAT), no significant losses were recorded. Application of various insecticides viz. dinotefuran 20 SG, triazophos 40 EC, chlorpyriphos 20 EC, monocrotophos 36 SL @ 200g, 500, 1250, 850 ml ha-1, respectively, and biopesticides viz. beauveria 106 spores ml-1, melia 5 per cent, eupatorium 5 per cent @ 5.0, 2.5, 2.5L ha-1, respectively, proved promising in checking hispa infestation, with dinotefuran being the most effective and more or less comparable with other insecticides. Among biopesticides, beauveria application provided a significant check. However, maximum returns were obtained from triazophos.
Open Access
POTENTIAL OF ENTOMOPATHOGENS IN INTEGRATED CONTROL OF WHITEGRUBS IN HIMACHAL PRADESH
(CSKHPKV, Palampur, 2018-10-15) Sanjta, Suman; Mehta, P.K
The bioassay studies of five entomopathogens viz. Beauveria bassiana, Metarhizium anisopliae, Heterorhabditis indica, Steinernema carpocapsae and Bacillus cereus were conducted against grubs of Holotrichia longipennis and Brahmina coriacea. The entomopathogenic fungi revealed decrease in susceptibility with increase in age. The LC50 values of B. bassiana for I to III instar grubs of H. longipennis ranged from 7.28 x 107 to 1.6 x 108 conidia/ml. In case of B. coriacea, the LC50 values for I to III instars were determined from 5.04x 107 to 1.17x 108 conidia/ml. In H. longipennis and B. coriacea, first instar grubs were 1.12 to 2.43 and 2.85 to 3.84 times more susceptible than second and third instar grubs, respectively. The LC50 values of M. anisopliae for I to III instars of H. longipennis were calculated from 4.36 x 107 to 1.3 x 108 conidia/ml. In case of B. coriacea, M. anisopliae produced 50 per cent kill at a concentration range of 4.9 x 109 to 3.2 x 108 conidia/ml in I to III instar grubs. In H. longipennis, first instar grubs were 2.06 and 2.98 times more susceptible than second and third instar. In case of B. coriacea, the increase in LC50 for second and third instar in comparison to first instar was 2.24 to 3.67 times. The grubs of H. longipennis were found comparatively more susceptible to both entomopathogenic fungi and B. bassiana was found to be less virulent as compared to M. anisopliae. Two entomopathogenic nematodes viz. H. indica and S. carpocapsae were evaluated by soil inoculation method. Against H. longipennis, the LC50 values of H. indica for I to III instars ranged between 324.15 to 796.18 IJs/ml. In case of B. coriacea, the LC50 values of H. indica against I to III instars were calculated from 444.84 to 845.18 IJs/ml. S. carpocapasae produced 50 per cent kill in respective instars of H. longipennis at concentrations ranging from 408.63 to 910.67 IJs/ml. In B.coriacea, a dose of 474.26 to 1620.34 IJs/ml of S. carpocapsae is required to produce 50% kill. There was 1.70 and 2.4 times increase in LC50 values of H. indica in first instar of H. longipennis as compared to second and third instars, respectively. In B. coriacea, the corresponding increase was 1.4 and 1.89 times. S. carpocapsae proved less effective as compared to H. indica, and H. longipennis was found to be more susceptible to entomopathogenic nematodes as compared to B. coriacea. B. cereus was found to be least effective among tested entomopathogens. In I to III instars of H. longipennis and B. coriacea, the LC50 values of B.cereus varied from 5.62 x 108 to 1.7 x 109 spores/ml. Among tested insecticides, clothianidin was found highly effective with LC50 values ranging from 129.86 to 457.11 ppm. In case of imidacloprid and chlorpyriphos, the LC50 values ranged from 238.38 to 811.81 ppm, and 334.44 to 911.44 ppm in different instars of H. longipennis and B. coriacea. To interaction studies of different entomopathogens with imidacloprid, chlorpyriphos and clothianidin have shown to produce strongest interaction with the tested insecticides in both the species of whitegrubs. Imidacloprid revealed maximum synergism with H. indica and S. carpocapsae. There was consistent antagonistic interaction among B. cereus and imidacloprid or chlorpyriphos. Under field conditions, combined application of H. indica+imidacloprid in potato gave 34.53 to 40.67 % reduction in tuber damage over control.
Open Access
Bioefficacy of biopesticides and novel insecticides to Leucinodes orbonalis Guenee and their safety to natural enemies
(CSKHPKV, Palampur, 2018-07) Sharma, Sugandha; Chandel, Y.S.
Studies on the bioefficacy of biopesticides and novel insecticides to L. orbonalis and their safety to natural enemies was undertaken at CSK Himachal Pradesh Krishi Vishvavidyalaya, Palampur. The lethal concentrations computed against first instar larvae of L. orbonalis revealed cyantraniliprole as most effective with LC50 and LC90 values of 0.18 and 0.95 ppm followed by chlorantraniliprole (1.24 & 8.64 ppm), thiacloprid (14.43 & 95.09 ppm), indoxacarb (19.99 & 106.71), lambda-cyhalothrin (38.62 & 207.78 ppm), azadirachtin (57.06 & 316.34 ppm), melia (73.82 & 378.09 ppm) and eupatorium (97.84 & 477.85 ppm). Under bioefficacy studies, chlorantraniliprole resulted in minimum shoot infestation followed by cyantraniliprole, lambda-cyhalothrin, thiacloprid, indoxacarb, azadirachtin, melia and eupatorium during 2015, whereas, during 2016 the shoot infestation was minimum in cyantraniliprole followed by chlorantraniliprole, thiacloprid, lambda-cyhalothrin, indoxacarb, azadirachtin, melia and eupatorium. Fruit infestation was found minimum in chlorantraniliprole followed by cyantraniliprole, thiacloprid, lambda-cyhalothrin, indoxacarb, azadirachtin, melia and eupatorium during both the years. On the basis of index of mean persistent toxicity of 2015 & 2016, the order of effectiveness of biopesticides and novel insecticides was: chlorantraniliprole (608.34) > cyantraniliprole (580.56) > thiacloprid (519.44) > lambda cyhalothrin (409.72) > indoxacarb (297.50) > azadirachtin (256.67) > melia (213.44) > eupatorium (136.11). Studies on dissipation pattern of insecticides revealed the average recovery of 87.75 and 91.10 per cent of indoxacarb and thiacloprid, respectively through RP-HPLC. The LOD and LOQ were 0.009 and 0.03 mg/kg for indoxacarb, 0.015 and 0.05 mg/kg for thiacloprid, respectively. The initial deposit of indoxacarb and thiacloprid were 0.620±0.025 and 1.078±0.011 mg/kg during 2016 with 0.4 and 1.6 day(s) waiting period, respectively and 0.622±0.015 mg/kg and 1.133±0.044 mg/kg during 2017 with 0.4 and 1.7 day(s) waiting period, respectively. Laboratory and field studies on relative safety of all the treatments to T. chilonis showed azadirachtin, chlorantraniliprole, cyantraniliprole, melia & eupatorium safer to the parasitoid and lambda-cyhalothrin as highly toxic.
Open Access
DISTRIBUTION AND BIOCONTROL POTENTIAL OF ENTOMOPATHOGENIC NEMATODES AGAINST SOME LEPIDOPTEROUS PESTS
(CSKHPKV, Palampur, 2014-01) Vashisth, Sumit; Chandel, Y.S.
ABSTRACT Survey for entomopathogenic nematodes (EPNs) was conducted in ten districts of Himachal Pradesh during 2011-13. In all, 930 soil samples from 131 locations were analysed for the occurrence of the nematodes. The frequency of occurrence of these nematodes was very low (3.82%). The nematodes were found in five locations i.e. Sangla (Distt. Kinnaur), Kamand (Distt. Kullu), Rajgarh (Distt Sirmour), Rajour and Sutkar (Distt. Chamba). These localities are situated in mid hill/high hill zones of the state. The nematodes were recovered from fruit orchards only having lighter soils. The nematodes from all the locations were identified as Heterorhabditis. Nematode cultures from different locations were considered as isolates and were designated as Sangla isolate, Kamand isolate , Rajgarh isolate , Sutkar isolate and Rajour isolate . Former three isolates, along with one commercial isolate i.e. H. indica (procured from NBAII, Bangluru) were evaluated for their pathogenic effects against Spodoptera litura, Helicoverpa armigera, Plutella xylostella and Agrotis segetum in Petri plates/soil/screen house. All these three local isolates including the commercial isolate proved pathogenic variably to different insect-pests. In screen house testing on cabbage, Rajgarh isolate was found highly effective against S. litura, H. armigera and P. xylostella. The virulence of these isolates was considered of the medium level. The bacterium, Photorhabdus luminescence was associated with all the isolates and proved non pathogenic to Achroia grisella when tested alone. Besides, host invasion studies in A. grisella revealed maximum penetration through natural openings, other than mouth. For in vivo mass production of local EPNs, Corcyra cephalonica, A. grisella and Bombyx mori were used. The average yield of IJs/larva was minimum (23020-26030) in C. Cephalonica and maximum in B. mori (463080-546840) for different EPNs. For in vitro production, chicken offal medium was used. The yield was maximum for Rajgarh isolate (17.70 x 106 IJs/flask).
Open Access
EVALUATION OF SOME PLANTS FOR THEIR INSECTICIDAL PROPERTIES AGAINST IMPORTANT LEPIDOPTEROUS PESTS
(CSKHPKV, Palampur, 2015-08) Singh, Kamal Deep; Mehta, P.K
ABSTRACT Four different plants viz., Acorus calamus L., Vitex negundo L., Adhatoda vaisca L. and Dioscorea deltoidea Wall. were evaluated for their biological activities against Plutella xylostella (L.) and Helicoverpa armigera (Hub). Four different solvents viz., methanol, hexane, ethyl acetate and aqueous extracts were used for extraction. LC50 values for methanol, ethyl acetate, hexane extract of A. calamus, methanol extract of V. negundo and ethyl acetate extract of A. vasica were 2.0203, 2.2938, 2.8474, 3.4600 and 4.1709 per cent for IInd instar larvae of P. xylostella, respectively. For H. armigera, LC50 values were 1.7495, 2.3296, 3.0859, 3.7773 and 4.0296 per cent for methanol, ethyl acetate, hexane extract of A. calamus, methanol extract of A. vaisca and ethyl acetate extract of V. negundo for IInd instar larvae of H. armigera. Different plant extracts also exhibited ovicidal asctivity against P. xylostella and H. armigera and resulted in 12.62 to 79.39 and 12.74 to 53.61 per cent reduction in egg hatching, respectively. Plant extracts from polar solevents were found to be more effective in reducing the hatchability as compared to non-polar. Maximum antifeedant activity (74.63 and 80.95% feeding inhibition) was observed in hexane and methanol extract of A. calamus for P. xylostella and H. armigera, respectively. Repellent effects showed that maximum repellency was observed in methanol extract of A. calamus (51.33%) and ethyl acetate extract of V. negundo (56.89%) for P. xylostella and H. armigera, respectively. Influences of the exposure of immature stages of P. xylostella and H. armigera to sub-lethal concentartion of different plant extracts resulted in increased duration of total developmental period of P. xylostella and H. armigera as compred to untreated check. However, per cent survival upto adult formation was decreased considerably. Morphogentic abnormalities in different developmental stages such as lack of melanization in larval and pupal stages, pupal-adult intermediate, folded wing or wing less adults were also observed. Lower values for Total growth index (TGI) for P. xylostella were observed, which varied from 1.74 to 6.39 as compared to 7.16 to 13.42 in untreated check. Similar results indicating low TGI were obtained in H. armigera. Adults emerging from treated larvae in both test insects reflected reduction in fecundity as compared to those emerging from untreated larvae. However, there was non-significant effect on the fertility of the test insects. In free choice test for recording oviposition deterrent activity against P. xylostella and H. armigera, low to moderate level of deterrence was evident (13.00 to 38.22%) and (13.67 to 36.29%), respectively. Field efficacy of different plant extracts revealed that hexane extract of A. calamus was most effective against H. armigera and methanol extract of A. calamus against P. xylostella and resulted in 48.91 and 55.51 per cent reduction in population after second round of spray, respectively.
Open Access
BIOECOLOGY AND MANAGEMENT OF RICE HISPA, DICLADISPA ARMIGERA (OLIVER) UNDER MID-HILL CONDITIONS OF HIMACHAL PRADESH
(CSKHPKV, Palampur, 2017-04) SHARMA, URVI; Srivastava, Ajai
Detailed studies on rice hispa, Dicladispa armigera (Oliver) were undertaken at CSK Himachal Pradesh Krishi Vishvidyalaya, Rice and Wheat Research Centre, Malan during 2014-2016. The studies included understanding rice hispa’s annual life cycle, its population build-up, assessment of losses inflicted and management with suitable insecticides and biopesticides. The life history of D. armigera consisted of four distinct stages viz. egg, grub, pupa and adult, each having an average duration of 4.5, 14.0, 9.1 and 22.4 (male); 38.7 (female) days, respectively. Both adults and grubs caused damage due to its feeding on paddy leaves. As many as 3-4 generations were recorded under laboratory conditions (mid June-mid November), but the adults of last generation failed to lay eggs. A few individuals of adults of last generation survived on rice seedlings and weed host, Cynodon dactylon (Linn.) till April-May with limited feeding and no egg-laying. Field observations recorded the incidence of hispa adults on wheat crop during February-April. With the early monsoon showers, the adults of hispa started appearing on weeds viz. C. dactylon, Cyperus rotundus (Linn.), Andropogon gayanus (Kunth), Digitaria sanguinalis (Linn.) and Panicum dichotomiflorum Michx., etc in the early June and thereafter it started feeding on paddy crop as soon as it was transplanted (July). During early stages of crop till 39th Standard Meteorological Week (SMW), both adult and grub incidence were recorded on paddy, which built-up during the season. Adults remained associated with the crop till its maturity. The population reached its peak during 31-39 SMW (August-September). Relative humidity significantly and positively influenced its build-up. Natural parasitization of grubs (or pupae) by a eulophid wasp, Chrysonotomyia sp. was reported. Damage and losses inflicted to paddy due to rice hispa as quantified by release density and phenological crop stage revealed that release at early stage (20-days after transplanting, DAT) inflicted more leaf damage (64.9 per cent leaf damage index, at 3-hispa release density) compared to later stages. Moreover, the regression analysis revealed that per unit increase in hispa density at early stage (20-DAT) resulted in 5.82, 5.73, 441.4 reduced number of tillers, panicles and grains, respectively, and the respective grain weight by 8.06g (per four rice hills). Also, at release stage of 40-DAT, the grain number and grain weight reduced significantly (b= 258.5 and 6.87, respectively), but at advanced release stage (60-DAT), no significant losses were recorded. Application of various insecticides viz. dinotefuran 20 SG, triazophos 40 EC, chlorpyriphos 20 EC, monocrotophos 36 SL @ 200g, 500, 1250, 850 ml ha-1, respectively, and biopesticides viz. beauveria 106 spores ml-1, melia 5 per cent, eupatorium 5 per cent @ 5.0, 2.5, 2.5L ha-1, respectively, proved promising in checking hispa infestation, with dinotefuran being the most effective and more or less comparable with other insecticides. Among biopesticides, beauveria application provided a significant check. However, maximum returns were obtained from triazophos.
Open Access
BIOEFFICACY AND PERSISTENCE OF BOTANICALS AGAINST INSECT- PESTS ON CAULIFLOWER
(CSKHPKV, Palampur, 2017-01-04) GHOSH, PALLAVI; Duni Chand, Sharma
Supercritical fluid extracts of eupatorium, melia and sarcococca were screened through technique-A (dry powder of botanicals replaced at every pressure) and technique-B (same dry powder used at subsequent pressures) at different pressures under laboratory for insecticidal activity. The higher insecticidal activity as well as extract yield were obtained using technique-A. The eupatorium extract obtained at 125 bar (LC50: 0.0055, 0.0040, 0.0004%) and melia (LC50: 0.0078, 0.0035, 0.0038%) and sarcococca (LC50: 0.0085, 0.0057, 0.0082%) at 100 bar pressure were found effective against B. brassicae, P. brassicae and P. xylostella, respectively and selected for the study on field evaluation against insect-pests of cauliflower, persistent toxicity and relative safety to predators. Based on different mode of entry of botanicals, the contact toxicity of azadirachtin was found to be the maximum followed by eupatorium extract. On the basis of stomach and both stomach and contact action, azadirachtin was highly efficacious followed by melia extract. Maximum antifeedancy was observed in azadirachtin (AC50: 0.0001, 0.0002%) followed by melia (AC50: 0.0078, 0.0107%), eupatorium (AC50: 0.0106, 0.0183%) and sarcococca (AC50: 0.0127, 0.0185%) against P. brassicae and P. xylostella. Similar trend was followed for repellent effect. Studies on variation in the insecticidal activity of eupatorium in different seasons and melia extract obtained from different drupe stages revealed that eupatorium extract of old leaves collected during summer and autumn season and melia extract of unriped drupes possessed maximum insecticidal activity. Bioefficacy studies conducted during three cropping seasons (2012-13 to 2014-15) at Experimental farm of Department of Entomology, CSK HPKV, Palampur revealed that among botanicals, azadirachtin (0.00045%) and melia (0.06%) were found most effective against all the tested insects and statistically at par with cypermethrin (0.01%). The order of effectiveness based on persistent toxicity value was cypermethrin > azadirachtin > melia (0.06%) > eupatorium (0.06%) > melia (0.03%) > sarcococca (0.06%) > eupatorium (0.03%) > sarcococca (0.03%). Studies on dissipation pattern of botanicals revealed the average recovery of 82.63 and 89.33 per cent of eupatorium and 88.04 and 89.63 per cent of melia through bioassay and LC MSMS was observed. The initial deposit of eupatorium, melia, sarcococca, azadirachtin and cypermethrin were 2.79, 2.80, 2.88, 2.07 and 3.13 ppm during 2014 and 2.92, 3.01, 3.01, 2.99 and 2.19 during 2015 with zero day waiting period for eupatorium, melia, sarcococca and azadirachtin and 1.89 days for cypermethrin, respectively. Studies on relative safety of botanicals for C. septempunctata showed that safety index was >16 in case of melia and eupatorium formulations, while for sarcococca it was >32 as compared to cypermethrin (1.52,1.23) for adults and grubs.
Open Access
BIOLOGY OF WHITEGRUBS IN RELATION TO PHYSICO-CHEMICAL PROPERTIES OF SOIL
(CSKHPKV, Palampur, 2016-07-25) KUMAR, SWAROOP; Chandel, R. S.
ABSTRACT In Himachal Pradesh, Brahmina coriacea, Holotrichia longipennis, Anomala dimidiata and Melolontha indica were found to be the important species endemic to Shimla, Kangra, Una and Mandi districts, respectively. The soil pH in the state ranged from 4.7 – 7.4, and organic carbon varied from 0.75 – 2.94 per cent. The observations on biology of B. coriacea, H. longipennis and A. dimidiata were recorded in soils collected from whitegrub endemic pockets. The incubation period was not affected by the soil type in any of the species, however, egg hatching was significantly affected ranging from 41.5 – 94.8 per cent in different species in different soils. The duration of first instar in B. coriacea and A. dimidiata, second instar in B. coriacea, H. longipennis and A. dimidiata and third instar in B. coriacea and H. longipennis was not affected in different soils. The duration of first instar in H. longipennis and third instar of A. dimidiata was significantly affected in different soils. Shortest duration of first instar of H. longipennis (11.7 days) and third instar of A. dimidiata (207.3 days) was recorded in Janjehli and Nauni soils, respectively. The larval survival differed significantly in most of the instars in different species. Overall value of larval growth index (0.22) was calculated to be maximum for B. coriacea in Seobagh soil. The pupal period in H. longipennis and A. dimidiata was not affected in different soils, but pupal survival in B. coriacea (16.7 – 81.0 %) and A. dimidiata (27.8 – 73.8 %), and pupal period in B. coriacea were significantly affected in different soils. The fecundity of B. coriacea was found to be maximum in Una soil. The females of H. longipennis and A. dimidiata deposited maximum eggs in Seobagh and Bharmour soils, respectively. Soil moisture conditions severely affected oviposition in different scarab species, and there was no egg laying at moisture percentage of ≥30 per cent. At 15 per cent soil moisture, significantly higher fecundity was recorded in all the species. Soil moisture at 15 per cent was found to be best for survival of grubs in all the species. The soil pH did not influence the incubation period, however, egg survival was significantly affected in B. coriacea (62.6 – 75.4 %) and A. dimidiata (59.9 – 84.1 %). In case of B. coriacea and A. dimidiata, higher egg survival was recorded at soil pH of 7.5. Duration of instars was not influenced by the soil pH, but larval survival was significantly affected in some species in some instars. Fecundity was not influenced by soil pH in B. coriacea and A. dimidiata, but in H. longipennis, significantly higher fecundity was recorded at pH 6.5. There was gradual decrease in hatchability of eggs with the increase in FYM in soil in all the species. Maximum egg hatching (74.91 – 81.46%) was recorded in soils having no FYM in different species. The larval survival was significantly affected in all the instars. Relatively higher survival of grubs was recorded at 0 – 25 per cent level of FYM in soil. The overall larval growth index was on higher side at 25 per cent level of FYM for B. coriacea (0.18) and H. longipennis (0.12). Fecundity of B. coriacea was recorded to be maximum (36.67 eggs/ female) at 25 per cent level of FYM, but in H. longipennis and A. dimidiata, the females deposited maximum eggs (59.0 and 42.33 eggs/female) in soils having no FYM.

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