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ThesisItem Restricted Host-parasitoid relationship between Pyrilla perpusilla (Walker) and Fulgoraecia melanoleuca (Fletcher) on sugarcane(Punjab Agricultural University, Ludhiana, 2021) Sharma, Tarun; Shera, P.S.The studies on the “Host-parasitoid relationship between Pyrilla perpusilla (Walker) and Fulgoraecia melanoleuca (Fletcher) on sugarcane” were conducted at the Punjab Agricultural University, Ludhiana during 2019 and 2020. Among the host stages, 4th instar nymphs and adult females were more suitable for the parasitoid, F. melanoleuca in terms of higher larval survival, adult emergence, more proportion of females in the progeny and higher fecundity. The exposure of 1st instar host nymphs to the parasitoid resulted in cent per cent mortality within two days before any signs of parasitism. None of the parasitized 2nd to 4th instar nymphs survived as normal adults as all the parasitized individuals died as nymphs, nymph-adult intermediates or weak adults. However, in case of parasitized 5th instar nymphs, 18.0 per cent adults were normal. The mean longevity of nymphs parasitized in the 3rd, 4th and 5th instars was prolonged significantly; maximum prolongation was in the 4th instar. However, longevity of nymphs parasitized in the 2nd instar was even less than un-parasitized ones. When host adults were offered to the parasitoid, there were significant differences in mortality of parasitized and un-parasitized adults. Further, parasitoid-induced prolongation in the longevity of the surviving parasitized adults was observed for both the sexes. Among different agro-climatic zones, population count of P. perpusilla and F. melanoleuca as well as natural parasitism was more in Jalandhar (central plain zone) as compared to Hoshiarpur (sub-mountainous undulating zone) and Fazilka (Western zone). The parasitoid remained active in overlapping stages during the months of April to November with peak activity in September month at all the locations. It overwintered in cocoon or egg stage on sugarcane trash from December to March months. Among the selected insecticides, chlorpyriphos 20 EC, imidacloprid 17.8 SL and fipronil 5 SC were comparatively toxic to the parasitoid, while pymetrozine 50 WG, chlorantraniliprole 18.5 SC, flubendiamide 480 SC and flonicamid 50 WG were harmless to moderately harmful. The prolonged pupal period, reduction in adult emergence and decreased adult longevity were the sub-lethal effects in the insecticides, chlorpyriphos 20 EC, imidacloprid 17.8 SL and fipronil 5 SC. Biopesticides (Bacillus thuringiensis var. kurstaki 0.5 WP, Metarhizium anisopliae 1.0 WP and Beauveria bassiana 1.0 WP) and botanicals (azadirachtin 1500 and 50000 ppm) were safer to all the stages of F. melanoleuca.ThesisItem Embargo Selective breeding for less stinging trait in Apis mellifera Linnaeus colonies(Punjab Agricultural University, 2022) Madaan, Anmol; Mohindru, BharthiStudies on ‘Selective breeding for less stinging trait in Apis mellifera Linnaeus colonies’ were carried out at Campus Apiary at Entomological Research Farm, Department of Entomology, Punjab Agricultural University (PAU), and at an isolated mating yard at PAU Seed Farm, Ladhowal, during 2021-2022. The studies comprised of screening 100 A. mellifera colonies for less stinging behaviour, selective breeding for development of less stinging colonies and assessment of gentle colonies for colony productivity and foraging activity. The defensive behaviour of the colonies was assessed by alarm pheromone assay. The observations recorded were time taken for the first sting (seconds), number of stings received per minute and number of bees recruited for defense per min and scores were given on a five-point scale of 1 to 5 wherein score of 1 represented the most aggressive and 5 represented the gentlest colony. Screening revealed that the mean number of stings per min, ranged between 1.33 to 22.67; depicting 23 colonies to be the gentlest (score 5) and four the most aggressive (score 1), whereas 49, 18 and 6 colonies scored 4, 3 and 2, respectively. Time taken to first sting, ranged between 3.00 to 23.00 s; two colonies took >20 s (score 5), 10 took 15-19.99 s (score 4), 26 took 10-14.99 s (score 3), 54 took 5.0-9.99 s (score 2) and 8 colonies took < 5 s (score 1) for the first sting. The number of bees recruited per min for defense ranged between 3.67 to 41.67; six colonies got score 5, 50 got score 4, 37 got score 3, five got score 2 and two colony scored 1. Based on the cumulative score from all the three parameters, 10 colonies scored 13-15, 50 got 10-12 score, 34 got 7-9 score and six got 4-6 score. From the 10 selected least stinging colonies, five daughter queens were reared from each. The comparative assessment of the defensive behaviour between selected mother colony, F1 colonies and control unselected colonies revealed that both mother and F1 colonies had lesser number of stings/min, took more time to first sting and had lesser number of bees recruited for defense thus depicting defensive behaviour to be heritable. For all the three defensive characteristics, among the 50 F1 colonies, there was 62 per cent improvement compared to just 10 per cent in the original stock of screened 100 colonies Correlation among the three defensive traits revealed that the number of stings/min was positively correlated with the number of bees recruited for defense and inversely with the time taken for first sting, implying that bees of a colony that sting more number of stings on the leather ball have more number of bees recruited for defense and take less time to initiate defense. Bee breeding for less stinging traits had no negative influence on colony growth, productivity and foraging activity. The information generated from the study on the less stinging behaviour of A. mellifera will be helpful in further bee breeding work towards developing less stinging A. mellifera strain.ThesisItem Restricted Biology and bio-intensive management of Conogethes punctiferalis (Guenee) in guava(Punjab Agricultural University, 2022) Vikramjeet Singh; Sandeep SinghThe present study entitled "Biology and bio-intensive management of Conogethes punctiferalis (Guenee) in guava" was conducted in the Fruit Entomology Laboratory, Department of Fruit Science, Fruit Research Farm, Punjab Agricultural University, Ludhiana, and University Seed Farm (USF), Ladhowal during October 2019 to May 2021. The life cycle of C. punctiferalis on guava was completed within 35-55 days, with incubation period and larval duration ranging from 2-4 and 15-23 days, respectively. A parasitoid Trathala sp. nr. flavoorbitalis was recovered from larvae/pupae of C. punctiferalis during February 2021. Among the homemade botanical formulations evaluated for management of C. punctiferalis in guava, homemade neem formulation @ 18 ml/L was most efficient in reducing per cent fruit infestation over control. There was 51.04 per cent reduction in damage over control, 1.55 MT increase in yield over control and Rs. 19634/acre increase in net income over control in rainy season crop at PAU, Ludhiana. In winter season experiment, there was 47.37 per cent reduction in damage, 1.51 MT increase in yield and Rs. 30359/acre increase in net income over control at USF, Ladhowal. Among biocontrol agents, Trichogramma chilonis @ 2000 parasitised eggs/ tree was most successful in containing the damage done by this pest in guava fruits in both rainy and winter season experiments conducted at Fruit Research Farm, PAU, Ludhiana and USF, Ladhowal, respectively. There was 73.57 per cent reduction in damage over control, 1.70 MT increase in yield over control and Rs. 21412/acre increase in net income over control in rainy season crop at PAU, Ludhiana. In winter season experiment, there was 62.50 per cent reduction in damage, 1.98 MT increase in yield and Rs. 40462/acre increase in net income over control at USF, Ladhowal. The best treatments were integrated into a BIPM modules and among the various BIPM modules, Module 3 consisting of burying infested fruits in augmentoria, installing light trap, clean cultivation, two sprays of homemade neem formulation @18 ml/L and three releases of T. chilonis @ 2000 parasitised eggs/tree was best, giving maximum reduction in damage over control at both the locations and achieving maximum net returns Over control. There was 63.92 per cent reduction in damage over control, 2.23 MT increase in yield over control and Rs. 43279/acre increase in net income over control at PAU, Ludhiana. There was 65.35 per cent reduction in fruit damage, 2.36 MT increase in yield and Rs. 46204/acre increase in net income over control at USF, Ladhowal.ThesisItem Restricted Evaluation of transgenic cotton expressing Tma12 gene against Bemisia tabaci (Gennadius)(Punjab Agricultural University, 2023) Rupinderjeet Kaur; Satnam SinghThe present study was conducted to evaluate the effectiveness of transgenic events expressing the insecticidal protein Tma 12 from the edible fern Tectaria macrodonta against whitefly, Bemisia tabaci (Gennadius). The evaluation was done based on comparative settling preference, fecundity, egg hatchability, nymphal development, and the expression of the Tma 12 gene in various events and checks. Transgenic events had no impact on whitefly settling preference, as it was primarily associated with trichome density and the mean whitefly number across events and checks ranged from 3.80 to 8.13 per 3 leaves. Weekly adult whitefly numbers were initially low in all transgenic events (35 to 38 SMW) but sharply increased later with the progression of time. The adult population ranged from 6.55 to 146.20 and 6.12 to 140.44 whitefly adults/3 leaves for events and non-events, and 7.85 to 93.05 nymphs/ disc and 3.14 to 113.19 nymphs/disc for transgenics and non-transgenics checks under multiple and no choice conditions. The Events 402 and 403 showed 12.70% and 11.67% lower adult populations but higher nymphal populations compared to controls under both multiple choice and no choice conditions. The Event 402 and Event 403 exhibited the lowest percentage emergence of I/II instar nymphs compared to other events and checks. The corrected mortality in the events ranged from 7.69 to 18.52% with 10.8 to 17.3% natural mortality in non-event Coker 312 and other checks. The expression of Tma 12 protein had no impact on cotton leaf curl virus incidence, with disease PDI (Percentage Disease Index) ranging from 51.39% to 63.13% across all tested events and checks. Continuous feeding of whitefly on transgenic events led to a decrease in fecundity ranging from 37.80% to 51.01% over generations, compared to the check Coker 312. Similar reductions were observed in hatching percentage in G3 (generation 3) with 37.78% and 29.05% decrease in Event 402 and Event 403, respectively compared to G0. The Tma 12 protein extended the total life cycle of whitefly by 2.52 days in Event 402 and 1.59 days in Event 403 compared to non-event Coker 312. Nymphal duration increased significantly, particularly in Generation I compared to Generation III, with a total life cycle extension of 2.29 days in Event 402 and 3.53 days in Event 403. The Events 402, 403, 384, and EP 14 exhibited 19.22%, 15.44%, 16.76%, and 14.36% whitefly mortality, indicating low to marginal control of whitefly with transgenic cotton expressing Tma 12 protein. The expression of Tma 12 gene showed consistent levels spatially and temporally. Event 402 and Event 403 with phloem driven promoter, exhibited significantly higher expression upon whitefly infestation compared to CMV promoter driven Event 384 and EP 14. Expression in Event 402 and Event 403 was 3.7 and 6.8 times higher than EP 14 and Event 384, respectively. Event 403 also showed 2.1 and 5.3 times higher expression compared to EP 14 and Event 384, respectively.ThesisItem Restricted Diversity, seasonal incidence and damage assessment of Oxycarenus spp. on cotton(Punjab Agricultural University, 2023) Noor Mahammed N R; Pandher, SuneetThe study on „Diversity, seasonal incidence and damage assessment of Oxycarenus spp. on cotton‟ was conducted at PAU, RRS Faridkot during Kharif 2022-23. Increasing incidence and damage incurred due to dusky cotton bug on cotton during the last few years necessitated to conduct the present study in north India. The results of first experiment were based on collection of dusky cotton bug samples from 31 locations spread across three states of Punjab, Haryana and Rajasthan and revealed that mt-COI gene based molecular identification doesn‟t confirm Oxycarenus at species level. The second experiment on seasonal incidence of dusky cotton bug was recorded on Bt cotton hybrid G. hirsutum RCH 650, non Bt G. hirsutum var. RS 2013 and G. arboreum var. LD 1019 at weekly intervals from 20 randomly selected plants (five squares/flowers/bolls) from each cultivar starting from the appearance of bugs (June) till the harvest of the crop (December). The results revealed that population of Oxycarenus spp. started during square formation stage (July last week), reached peak (around 100 bugs per 5 bolls) during complete boll opening stage (November second week) and remained present till the harvest of crop. Among the weather variables, RH max was positively correlated with the Oxycarenus spp. population, whereas Tmax, Tmin, Tmean, RH min and RH mean were highly significant and negatively associated. Continuous heavy rainfall with non-availability of opened bolls during third week of July has high negative impact on dusky population. Using pest-weather regression models, Oxycarenus spp. incidence on RCH 650, RS 2013 and LD 1019 may be forecasted with good accuracy i.e., R²=0.86, 0.89 and 0.87, respectively. In the third experiment, study on extent of loss caused by Oxycarenus spp. was carried on Bt cotton hybrid RCH 650 under screen house conditions with five treatments (0, 25, 50, 75 and 100 bugs per boll) replicated sixteen times. Bolls of uniform size were selected and covered with perforated net sleeves/cages to prevent natural incidence of Oxycarenus spp., later bugs were released into sleeves and left for 35-40 days. The results revealed that highest damage w.r.t boll weight, seed weight, 100 seed weight and germination was observed in 100 bugs per boll treatment, whereas lint staining (brownish) was very high in 75 and 100 bugs per boll treatment. It can be concluded from the above experiment that as the bug incidence per boll increases, the seed characters are severely affected. The fourth experiment on bio efficacy of homemade neem extracts against Oxycarenus spp. was carried out on Bt cotton hybrid US 51 and dusky cotton bugs along with natural enemies count were recorded (before spray, 3, 7, and 14 days after spray) twice during the entire cropping period. The results revealed that around 50 per cent reduction over control can be achieved by spraying neem formulations, indicating effective alternative approach to synthetic insecticides in pest management. Nimbecidine @ one litre per acre and homemade neem formulations @ 1.5 litre per acre were found effective against Oxycarenus spp. up to 7 days of spraying and neem formulations‟ effect on predators and especially spider population was found to be non-significant during the spray schedule.ThesisItem Embargo Eco-friendly management of Tetranychus urticae Koch on brinjal under protected cultivation(Punjab Agricultural University, 2023) Dinesh Kumar; Parmjit KaurBrinjal is a highly remunerative vegetable crop grown throughout the world under protected cultivation and sucking pests are a major hindrance in its cultivation. In the present studies, population dynamics of red spider mite, Tetranychus urticae Koch was observed under protected cultivation. It was observed that the population of T. urticae was found to be significantly positively correlated with maximum temperature and average temperature while non-significantly positively correlated with minimum temperature whereas it was significantly negatively correlated with morning relative humidity (MRH), evening relative humidity (ERH) and average humidity. The avoidable crop loss in yield caused by T. urticae on brinjal was observed to be 19.07 per cent in July transplanted crop and 20.09 per cent in February transplanted crop. The efficacy of various plant extracts at different doses against T. urticae on brinjal under protected cultivation was tested at two locations. PAU homemade neem extract, PAU homemade pongamia extract both @ 14 and 16 ml per litre and neem fruit aqueous extract @ 6 per cent were effective in controlling mite population as they gave more than 60 per cent reduction in mite population after seven days of second spray. Different indigeneous/homemade/Gurukul products and predators against T. urticae on brinjal under protected cultivation were also tested. Among these products, Agniastra and Neemastra both @ 10 and 12 ml/litre gave best results and reduction in these treatments was more than 60 per cent after seven days of second spray. Among predators, Anthocorid bug, Blaptostethus pallescens Poppius@20 nymphs/plant and phytoseiid mite, Neoseiulus longispinosus Evans@1:20, 1:30 and 1:40 reduced T. urticae population by more than 70 per cent where as B. pallescens @ 30, 40 per plant reduced the mite population by more than 80 per cent. Therefore, we can incorporate these plant extracts, indigenous/homemade/Gurukul products and predators in integrated management of mites on brinjal under protected cultivation.ThesisItem Restricted Influence of temperature on growth and development of Pectinophora gossypiella (Saunders) in Bt cotton(Punjab Agricultural University, 2023) Patina Harshavardhan; Amandeep KaurThe study on „Influence of temperature on growth and development of pink bollworm in Bt cotton‟ was studied at various alternate temperatures (20:30oC, 24:30oC,28:30oC, 20:35oC, 24:35oC, 28:35oC, 20:40oC, 24:40oC and 28:40oC) in Integrated Pest Management Laboratory, Department of Entomology, PAU, Ludhiana during 2022-23 cotton growing season. The results of first experiment revealed that the first, second, third, fourth larval instars and total larval duration were significantly shorter at an alternating temperature of 28:40oC. The pupal duration, adult longevity and total developmental period of male and female were recorded significantly lower at an alternate temperature of 28:40oC. The fecundity and egg, larval and pupal survival was recorded highest at an alternate temperature of 28:30oC, whereas the larval and pupal weights were recorded highest at an alternate temperature of 28:35oC. The correlation was worked out where the developmental parameters and fecundity shown significant negative correlation, the survival of egg, larva and pupa show non-significant negative correlation, whereas the larval and pupal weights show non-significant positive correlation with alternate temperatures. The second experiment on „Influence of constant temperatures (15±1oC, 20±1oC, 25±1oC, 30±1oC, 35±1oC and 40±1oC) on growth and development of P. gossypiella in Bt cotton‟ was carried out. The results revealed that the all the larval instars and duration were significantly lower at constant temperature of 35±1oC. The pupal duration, adult longevity and total developmental period of male and female were recorded significantly lower at constant temperature of 35±1oC. The fecundity and egg, larval and pupal survival was recorded highest at constant temperature of 30±1oC and the larval and pupal weights were recorded highest at constant temperature of 35±1oC. The correlation was worked out where the developmental parameters have shown significant negative correlation with constant temperatures. All the larval instars and male pupal weights show significant positive correlation with constant temperatures and female pupal weight, egg, larval and pupal survival show non-significant positive correlation with constant temperatures. In the third experiment, the observation on effect of alternating temperatures on food consumption and nutritional indices of P. gossypiella in Bt cotton was also carried out and result revealed that the maximum food consumed and nutritional indices (Consumption index, Relative growth rate, Approximate Digestibility, Efficiency of conversion of ingested food) was recorded highest at an alternate temperature of 28:35oC.ThesisItem Embargo Management of Pyrilla perpusilla (Walker) with ecto-parasitoid, Fulgoraecia melanoleuca (Fletcher) on sugarcane(Punjab Agricultural University, 2022) Augustine, Neethu Maria; Shera, P SThe studies on “Management of Pyrilla perpusilla (Walker) with ecto-parasitoid, Fulgoraecia melanoleuca (Fletcher) on sugarcane” were conducted at the Punjab Agricultural University (PAU), Ludhiana during 2021-2022. The releases of F. melanoleuca cocoons (2000, 4000 and 6000 cocoons ha-1) and eggs (2, 4 and 6 lakh eggs ha-1) were compared with chemical control (chlorpyriphos 20 EC @ 1500 ml ha-1) and untreated control. The overall number of pyrilla nymphs and adults was significantly reduced after two releases of parasitoid eggs and cocoons. The reduction of pyrilla population creased progressively either with increase in number of released cocoons (2000, 4000 and 6000 ha-1) or with released eggs (2, 4 and 6 lakh ha-1). The nymphal and adult parasitism also increased with increase in doses and time and it was significantly higher when parasitoids were released at higher doses, i.e. 6 lakh eggs ha-1 (53.75 %) and 6000 cocoons ha-1 (50.60 %) as compared to lower ones. The augmentative releases of parasitoid eggs and cocoons plays a noteworthy role in increasing the parasitoid count (egg masses, cocoons and adults) in the released plots with time. However, chlorpyriphos 20 EC was found to be highly detrimental to the parasitoid as no parasitism and population count was observed in insecticide sprayed plots. Overall, two releases of F. melanoleuca eggs (6 lakh ha-1) or cocoons (6000 cocoons ha-1) at monthly interval (1st week of August and 1st week of September) proved better with respect to reduction in pyrilla population, increase in parasitoid population and parasitism rate and also rendered higher cane yield and better juice quality. The storage of F. melanoleuca eggs and cocoons at different temperatures (0, 5, 10 and 150C) for various durations (1, 2, 3, 4, 5 and 6 weeks) was compared with ideal temperature (270C) for the overall fitness of the parasitoid. The cocoons of F. melanoleuca can be stored at 100C for 1 week and at 150C for 1-2 weeks as these temperature regimes and storage time exhibited negligible negative effect on developmental and reproductive parameters of the parasitoid. Similarly, eggs can be stored at 150C for 1week without much negative effect on hatchability and incubation period of the parasitoid.ThesisItem Embargo Effect of weather parameters on growth and development of Spodoptera frugiperda (J. E. Smith) in maize(Punjab Agricultural University, 2022) Pukhraj Singh; Aggarwal, NaveenThe studies on the effect of weather parameters on growth and development of Spodoptera frugiperda (J.E. Smith) in maize were conducted on PMH 10 hybrid under laboratory conditions at five alternating temperature viz., 18:07, 24:12, 28:17, 32:22 and 36:27°C. The different developmental stages of S. frugiperda were influenced by temperature. The duration of different developmental stages viz., incubation, larva, pupa, and adult reduced with increase in temperature combinations of 18:7, 24:12, 28:17, 32:22 and 36:27oC. Maximum per cent hatchability (94.66%) was recorded at 36:22oC whereas no eggs hatched at 18:07oC. The larval survival was maximum (88%) at 36:27oC and minimum (66%) at 24:12°C. The larval duration was longer (29.50±0.24 days) at 24:12oC. It was significantly shorter (11.98±0.25 days) at 36:27°C. The minimum pupal survival of 68 per cent was recorded at 24:12oC. It was significantly more (96%) at 32:22°C. Pupal period was significantly longer (24.7±0.13 days) at 24:12oC and shorter (8.8±0.09 days) at 36:27°C. Overall, total life cycle of S. frugiperda took longer 68.06±0.49 days at 24:12°C and shorter duration of 29.38±0.65 days at 36:27°C. Maximum adult emergence of 80.64 per cent was recorded at 32:22°C while it was minimum (44.88%) at 24:12°C. The maximum male to female sex ratio of 1:1.80 was recorded at 36:27°C whereas minimum ratio of 1:1.27 was observed at 28:17°C. Fecundity increased significantly with increase in temperature being maximum (925.64 eggs/female) at 36:27°C and minimum (719.72 eggs/female) at 24:12°C. The adult longevity was maximum (male: 8.66±0.07; female: 9.46±0.04 days) at 24:12°C whereas lowest (male: 6.06±0.05; female: 6.82±0.05 days) at 36:27°C, respectively. The thermal constant for egg, larval, pupal and adult stages was found to be 45.45, 333.33, 166.67 and 125.00 Degree Days (DD), respectively totalling to 670.45 DD while, the lower developmental threshold was found to be 12.59, 12.33, 12.67 and 10.50oC for the respective stages. The dimensions of all the developmental stages (egg, larva, pupa and adult) of S. frugiperda were recorded to be increased with increase in test temperature combinations. Population growth parameters viz., net reproductive rate (R0), mean generation time (Tc), intrinsic rate of increase (rm), finite rate of increase (λ) and doubling time (DT) were influenced significantly by temperature. Among various life table parameters, highest net reproductive rate of 393.61±0.61 females/ female was observed at 32:22oC, whereas mean length of generation and doubling time was longest at 24:12oC. The innate capacity for increase and finite rate of increase was recorded highest at 36:27oC. The biology of S. frugiperda studied at different combinations of alternating temperatures of 24:12 and 32:22oC and carbon dioxide (CO2) levels of 375 ppm and 450 ppm revealed temperature as the major factor influencing the biology. As the temperature increased, the duration of growth stages viz., egg, larval, pupal and adult stages decreased and fecundity increased and same trend was also observed with increase in CO2 levels.
