Theses

Browse

Search Results

Now showing 1 - 9 of 20

Open Access
Impact of habitat manipulation and biorationals on major insect pests of cabbage and their natural enemies
(CCS HAU, Hisar, 2022-07) Jeevan B G; Kalkal, Deepika
Studies were carried out on habitat manipulation and effect of biorationals on major insect pests of cabbage and their natural enemies during Rabi, 2021-22 at HAU, Hisar. The experiment was carried out to access the impact of different cropping patterns, viz., T1 [cabbage + coriander as border crop], T2 [cabbage + mustard as border crop], T3 [cabbage + marigold as border crop], T4 [cabbage +fenugreek (3:1)], T5 [cabbage + marigold (3:1)], T6 [cabbage + fennel (2:1)] T7 [cabbage + coriander (2:1) + fennel as border crop], T8 [cabbage + mustard (2:1) + fenugreek as a border crop] and T9 [Control (Cabbage as sole crop)] on three insect pests viz., mustard aphid, diamondback moth and cabbage butterfly and two natural enemies viz., coccinellids and syrphid fly. Results on habitat manipulation revealed that lowest mean population of aphid and cabbage butterfly was found in T8 with 8.10 aphids/plant and 3.47 larvae/plant, respectively while highest in T6 with 13.38 aphids/plant and 5.13 larvae/plant, respectively whereas, DBM larval population was found lowest in T7 with 0.61 larvae/plant and highest in T3 [cabbage + marigold as border crop] with 1.15 larvae/plant. For increasing the population of coccinellids and syrphid fly treatment T7 was found best with highest population 3.44 coccinellids/plant and 1.57 maggots/plant, respectively. Aphid population shows significant positive correlation with morning relative humidity and negative correlation with maximum temperature and coccinellid population. Larval population of DBM (P. xylostella) showed significant positive correlation with maximum temperature and negative correlation with morning and evening relative humidity. Cabbage butterfly, P. brassicae larvae population showed significant positive correlation with maximum temperature and evening relative humidity and negative correlation with morning and evening relative humidity and aphid population. Syrphid fly maggot population also showed significant negative correlation with evening relative. Maximum cabbage yield (180.62 q/ha) was recorded in the treatment T2 with third highest B:C ratio (2.46) while the first highest B:C ratio (3.38) was observed in T5. Results of bio-efficacy of eleven treatments (nine biorationals and one chemical along with unsprayed control) revealed that malathion 50 EC (as check) recorded maximum per cent reduction over control against both mustard aphid (62.24 %) and diamondback moth (52.14 %). Among biorationals, L. lecanii (1x108cfu/g) and azadirachtin 0.15% exhibited maximum per cent reduction over control against mustard aphid and DBM with 53.75 % and 47.66 %, respectively. However, maximum population of coccinellids (2.52 coccinellids/plant) and syrphids (0.76 maggots/plant) was recorded in L. lecanii(1x108cfu/g) and (B. thuringiensis var. kurstaki 0.5 % WP), respectively. Maximum yield of 198.69 q/ha was recorded in malathion 50 EC whereas the highest yield among biorationals was recorded in L. lecanii (1x108cfu/g) with 186 q/ha. The benefit cost ratio for efficacy was found highest (2.58) in treatment malathion 50 EC followed by L. lecanii (1x108cfu/g) with B:C ratio 2.36 and azadirachtin 0.15% with B:C ratio 2.20. The control had the lowest benefit cost ratio, B:C (1.72).
Open Access
Biology, population dynamics and management of fall armyworm, Spodoptera frugiperda (J.E. Smith) on maize
(CCSHAU, Hisar, 2021-09) Deepak Kumar; Maha Singh
The present investigation entitled, “Biology, population dynamics and management of fall armyworm, Spodoptera frugiperda (J.E. Smith) on maize” was carried out at Research Farm and laboratories, Department of Entomology, CCS Haryana Agricultural University, Hisar and Research Farm CCS Haryana Agricultural University Regional Research Station, Uchani, Karnal during Kharif, 2020. The biology of S. frugiperda was observed at four different temperatures viz., at room temperature, 15°C, 25°C and 35°C, respectively. The average fecundity of S. frugiperda was 1110.6, 714.8, 1303.9 and 1013.1 eggs/female at room temperature, 15°C, 25°C and 35°C, respectively. Egg hatchability was observed as 93.3, 74.9, 83.5 and 92.5 per cent whereas incubation period as 2.68, 6.08, 3.24, 2.80 days at room temperature, 15°C, 25°C and 35°C, respectively. Average larval period was 15.44, 32.97, 19.96 and 15.09 days whereas larval survival as 85.6, 58.8, 62.4 and 84.3 per cent at room temperature, 15°C, 25°C and 35°C, respectively. Pupal period was noticed as 7.78, 25.63, 9.28 and 7.42 days whereas the adult emergence as 64.2, 52.0, 63.0 and 68.5 per cent at room temperature, 15°C, 25°C and 35°C, respectively. Total life cycle of females was observed as 35.13, 79.33, 45.19 and 34.73 days while those of males as 33.24, 77.05, 42.71 and 32.46 days at room temperature, 15°C, 25°C and 35°C, respectively. Studied on population dynamics of S. frugiperda revealed that larval population prevailed from 28th SMW to 40th SMW. Its peak was observed during the 33th SMW with a mean population of 4.93 larvae per plant. The average plant infestation was observed from 28th SMW to 40th SMW (second week of July to first week of October) with a maximum of 79.1 per cent during 40th SMW. Larval population had a significant positive correlation with evening relative humidity (r = 0.652) and significant negative correlation with sun shine hours (r = -0.634) whereas per cent plant infestation indicated a non-significant correlation with all the weather entities. During the study period, three hymenopteran larval parasitoids (Chelonus sp., Cotesia sp., Campoletis sp) were also observed. Studies on screening of maize genotypes against S. frugiperda indicated that amongst the 55 maize genotypes, HM 10 recorded lowest leaf injury (4.45 score), while HKI 1348-6-2 recorded highest leaf injury (8.85 score). Five genotypes (HKI 1105, HKI 139, HKI 193-2, HKI 1011 and HM 10) were categorized as partially resistant (leaf injury score: 4.0 to 5.99), 20 genotypes as susceptible (leaf injury score: 6.0 to 7.99) and 30 genotypes as highly susceptible (leaf injury score: 8.0 to 9.00). Studies on effect of date of sowing on incidence of S. frugiperda indicated that plant infestation and larval population was observed minimum when crop was sown during last week of June while infestation and larval population gradually increased as date of sowing is delayed.
Open Access
Studies on insect pest complex of guava (Psidium guajava L.) with special reference to Bactrocera spp.
(CCSHAU, Hisar, 2021-08) Aarti; Ram Karan
The studies entitled “Insect pest complex of guava (Psidium guajava L.) with special reference to Bactrocera spp.” were carried out during 2020-21 at guava orchard of CCS Haryana Agricultural University, Regional Research Station (RRS), Bawal. Population dynamics of insect pest; incidence of fruit flies, fruit borer, bark eating caterpillar, red banded thrips and mealy bug was recorded. The first appearance of fruit fly was recorded in 16th standard meteorological week (SMW), 2020 and maximum fruit fly (132/trap/week) were recorded during 35th SMW, while fruit infestation by fruit fly was initially noticed during 25th SMW, 2020 and peak fruit infestation (75.0%) was recorded during 35th SMW. The castor capsule borer infestation was noticed in 28th SMW and maximum fruit infestation (12.0%) was during 43rd SMW. The castor capsule borer was not appeared during hasth bahar fruiting season. The first symptoms of bark eating caterpillar infestation recorded on 2nd fortnight of April, 2020 and maximum plant infestation (70.0%) with active holes 6.00 leaded to index of incidence 4.2 recorded on 2nd fortnight of August. There was no further increase in infestation of bark eating caterpillar after September. The first appearance of red banded thrips was recorded in 19th SMW, 2020 and maximum population (24.0/5apical shoots) recorded during 26th and 27th SMW. The maximum population of mealy bug (34.0/5apical shoots) recorded during 26th SMW. In correlation studies minimum temperature, relative humidity shows a highly significant and positive effect on all the insects. Two species of fruit fly, namely Bactrocera dorsalis and Bactrocera zonata were found in guava orchard. The maximum population of both species were found in 35th SMW, while B. dorsalis (55.13%) was dominant over B. zonata (44.87%). Maximum number of pupae were found in the 2nd fortnight of August and their viability was maximum in the 1st fortnight of July. The varietal/germplasms screening revealed that among the six varieties/germplasms screened, the susceptibility against fruit fly was maximum in Banarsi Surkha sequentially followed by L-49, Hisar Surkha, Allahabadi Safeda, Hisar Safeda and Desi. The correlation studies of physical traits showed that fruit firmness have highly significant and negative impact on fruit fly infestation while fruit weight, fruit size are positively related. The correlation studies of biochemical traits such as TSS, Vitamin C and total phenol showed highly significant and positive effect on fruit fly infestation, while acidity showed negative effect on fruit fly infestation. An analysis of all the parameters revealed that no single factor governed the fruit fly infestation independently and that the level of infestation was the result of the combined effects of all the factors.
Open Access
Studies on resource partitioning by honey bees and nectar secretion rhythms in different Brassica spp
(CCSHAU, Hisar, 2021-02) Jyoti; Yadav, Sunita
The present study was carried out on eleven genotypes/varieties belonging to eight Brassica spp. at Research Area of Oilseeds Section, Department of Genetics and Plant Breeding, CCS Haryana Agricultural University, Hisar during 2019-20. The flowering phenology of various rapeseed-mustard genotypes/varieties showed that flowering initiation and cessation was earliest on TH 68 (32.67 and 81.67 DAS) while total flowering period was highest on RH 725 (53.00 DAS). The flower morphological parameters i.e. flower length, flower breadth, corolla and calyx length of different genotypes varied from 1.41 to 1.74 cm, 1.42 to 2.23 cm, 0.76 to 1.14 cm, 0.49 to 1.06 cm respectively and flower color was bright yellow in all genotypes/varieties. Eighteen bee species belonging to twelve families of five orders (Hymenoptera, Diptera, Lepidoptera, Hemiptera and Coleoptera) were recorded. The Apis spp. were most abundant on variety TH 68 (16.77 bees/m2/10 min). The mean densities of A. mellifera was maximum (15.50 bees/m2/10 min) followed by A. cerana (12.90 bees/m2/10 min), A. dorsata (12.25 bees/m2/10 min) and A. florea (9.37 bees/m2/10 min). The foraging rate of Apis spp. was highest on HNS 0901 (15.16 flowers/min). The mean foraging rate of A. cerana was maximum (18.06 flowers/min) followed by A. dorsata (16.65 flowers/min), A. mellifera (16.66 flowers/min) and A. florea (6.57 flowers/min). The comparative mean time spent per flower was highest on variety T-27 (3.52flowers/sec). The mean foraging speed of A. florea was maximum (6.38 flowers/sec) followed by A. dorsata (2.39 flowers/sec), A. mellifera (1.94 flowers/sec) and A. cerana (1.83 flowers/sec). Highest mean percentage of nectar, pollen and both nectar plus pollen gatherers were observed at 2nd fortnight of December i.e. 37.67, 24.84 and 43.08 per cent respectively. Top workers were highest in case of A. dorsata (97.33%) followed by A. mellifera (90.33%) A.cerana (90.00%) and A. florea (66.33%) and the highest percentage of side workers was observed in A. florea (43.33%) followed by A. mellifera (21.00%), A. cerana (21.33%) and A. dorsata (4.33%). The maximum DNS was produced by the flowers of HC-212 and T-27 (1.50 and 1.49 mg/flower) and also amount of energy produced by nectar was highest in HC-212 and T-27 (25.11 and 24.92 joules energy). Abundance of all four honey bee species showed positive non-significant correlation with maximum and minimum temperature. Relative humidity was significantly positive correlated with the abundance of. A. mellifera, A. cerana, A. dorsata but showed non-significant positive correlation in case of A. florea at morning and analysis of relative humidity resulted significant positive correlation with the all bees at the evening. Wind speed showed significant positive correlation with all Apis spp. and sunshine hours were non-significantly correlated.
Open Access
Studies on biodiversity and DNA barcoding of predatory ladybird beetles (Coleoptera: Coccinellidae) in Haryana
(CCSHAU, Hisar, 2020-08) Mohammad Thamseer M K; Yadav, S.S
The biodiversity of predatory ladybird beetles was investigated in the state of Haryana,India. The predators were collected from natural and manipulated ecosystems across the state by hand collection. The collected specimen were identified with appropriate taxonomic keys. The state presented a highly abundant but less diverse ecosystem with respect to coccinellid predators. 2253 specimen of 20 species belonging to coccinellidae were collected from 17 ecosystems. The Shannon-weiner index,Simpson’s index,Effective number of species,Margalef’s index and Pielou’s evenness index were calculated for different ecosystems and it was found that sheesham (Dalbergia sisoo) and Okra (Abelmoschus esculentus) was ecologically the most diverse ecosystem in the state. The diversity indices of the predators in the state was very low for most of the crop ecosystems which can be attributed to the fact that the state is one of the leading consumer of insecticides in the country. Thus, the present data reflects on the grave consequences of indescriminate usage of pesticides on the natural enemies which, if left unchecked, can cause potential localised extinction of predatory fauna. DNA of the six species among the collection were successfully barcoded and the phylogenetic tree revealed a close relationship between Chilocorinae and Scymninae. The temporal distribution of the major aphidiphagous predators in wheat ecosystem revealed the presence of five major predators including two syrphids viz., Episyrphus viridaureus and Ischiodon scutellaris and three coccinellids viz., Hippodamia variegata, Cheilomenes sexmaculata and Coccinella septempunctata. The cumulative population of the predators had significant positive correlation with aphid population (r= 0.999).
Open Access
Seasonal variation in bee venom extraction and its effect on Apis mellifera L. colony performance
(CCSHAU, Hisar, 2021-08) N. Aparna; Yadav, Sunita
The present investigation entitled “Seasonal variation in bee venom extraction and its effect on Apis mellifera L. colony performance” was carried out at Apiary, Department of Entomology, CCS Haryana Agricultural University, Hisar during winter, spring and summer season in the year 2020-2021. The effect of various factors like frame strength, period of exposure and season on bee venom extraction and further impact of electrical bee venom extraction on honey bee colony behaviour and colony performance were examined. It was observed that 10 frame hives (0.016 g/colony) produced more bee venom than 6 frame hives (0.009 g/colony). Hives exposed for 60 minutes (0.016 g/colony) extracted more bee venom than 45 minutes (0.012) and 30minutes (0.007 g/colony) of exposure. Spring season (0.015 g/colony) noticed with maximum bee venom collection followed by winter (0012 g/colony) and summer (0.008 g/colony). Similar trend was observed in case of bee mortality due to electrical bee venom extraction. 10 fame hives (4.72 workers/colony) noticed with more number of dead bees/colony than 6 frame hives (3.52 workers/colony). Colonies exposed for 60 minutes (4.95 workers/colony) experienced more death than 45minutes (4.17 workers/colony)and 30 minutes (3.25 workers/colony) of exposure. Spring season (8.72 workers/colony) was noticed with maximum bee mortality followed by winter (2.33 workers/colony) and summer (1.31 workers/colony). Among the treatments also T6 (colonies with 10 frame and 60 minutes of exposure) produced more bee venom 0.022 g/colony) and noticed with maximum mortality (5.61 workers/colony) than other treatments. When bee venom amount was compared in relation with bee mortality, it was observed that colonies with highest strength (10 frames), longer duration of exposure(60 minutes) and winter season were the most productive and the safest for bee venom extraction compared to respective other factors due to the widest difference between bee venom amount and bee mortality. Significant difference was also observed because of different frame strengths in foraging behaviour, worker brood rearing, drone brood rearing, fecundity, sealed honey storage and pollen storage of the experimental colonies, although, duration of exposure didn’t have any significant effect on colony behaviour and performance parameters. This rendered the evidence of safety and efficacy of the bee venom extractor apparatus used in the investigation.
Open Access
Seasonal abundance and management of sucking insect pests on chilli (Capsicum annuum L.)
(CCSHAU, Hisar, 2021-09) Yadav, Sova; Lomash Kumar
The investigation on seasonal abundance and management of sucking insect pests on chilli (Capsicum annuum L.) were conducted during Kharif, 2020 at CCS HAU, Hisar. Studies on population dynamics of major sucking insect pests revealed that the incidence of thrips, Scirtothrips dorsalis, whitefly, Bemisia tabaci and leafhopper, Amrasca bigutulla bigutulla along with abundance of lady bird beetle, Coccinella septempunctata observed to appear on the chilli crop soon after transplanting. Incidence of thrips commenced in 19th Standard Meteorological Week (SMW) and attained its peak on 25th SMW (18.83 thrips /3 leaves /plant) while infestation of whitefly was initiated in 20th SMW then it increased gradually and reached to its peak in 25th SMW (21.20 whitefly/3 leaves /plant). The peak population of leafhopper was recorded in 26th SMW (10.4 leafhopper /3 leaves /plant). In case of lady bird beetle, population ranged from 0.20 to 0.93 per plant and was on the entire crop growth period (18th-37th SMW). Thrips and whitefly exhibited highly significant positive correlation with maximum temperature, negative non-significant correlation with evening relative humidity and non-significant correlation with wind speed, sunshine hours and pan evaporation while negative non-significant correlation with rainfall. Leafhopper population showed highly significant positive correlation with minimum temperature, non-significant negative correlation with maximum temperature, non-significant positive correlation with morning and evening relative humidity, sunshine hours and rainfall while negative non-significant correlation with wind speed and pan evaporation. Whereas, ladybird beetle exhibited positive non-significant correlation with maximum temperature, wind speed, sunshine hours and negative non-significant correlation with minimum temperature, morning and evening relative humidity, pan evaporation and rainfall. Among twenty genotypes screened, 19/CHIHyb-5 was found to be best against thrips and whitefly had least leaf curl index, maximum fruit yield and were graded as resistant while genotype 18/CHIHyb-5 was observed best against leafhopper. Evaluation of seven newer insecticides revealed that combination of diafenthiuron 40.1% + acetamiprid 3.9% WP @ 600 ml ha-1 was found to be more effective for maximum mean reduction in population of thrips, whitefly and leafhopper over untreated control followed by cyantraniliprole 10.26% OD @ 600 ml ha-1 also maximum yield (66.73 q/ha) was obtained from plot treated with diafenthiuron40.1% + acetamiprid 3.9% WP @ 600 ml ha-1. Neem seed kernal extract 5% was registered safer towards lady bird beetle.
Open Access
Incidence of major insect-pests, genotypes evaluation and management of pod borer complex in pigeonpea
(CCSHAU, Hisar, 2020) Kanchan; Verma, Tarun
Experiment on “Incidence of major insect-pests, genotypes evaluation and management of pod borer complex in pigeonpea” was conducted during kharif, 2019. Four pigeonpea genotypes (PAU 881, AL 1747, Paras and UPAS 120) were sown to study incidence of Helicoverpa armigera, Maruca vitrata, Clavigralla gibbosa and Empoasca kerri. Incidence of H. armigera commenced in 37th Standard Meteorological Week (SMW), remained upto 48th SMW, reached it’s peak in 44th SMW and population ranged from 0.05 to 0.45 larvae per plant. Web formation by M. vitrata and larvae started to appear from 37th SMW and persisted upto 43rd SMW. Peak of M. vitrata larvae was in 39th SMW (in Paras) and 40th SMW (AL 1747, UPAS 120 and PAU 881). Number of webs, larvae of M. vitrata ranged from 0.94 to1.23 webs per plant and 0.05-0.90 larvae per plant, respectively. Clavigralla gibbosa (Nymph and adult) incidence started from 36th SMW and continued upto 47th SMW. Adults of C. gibbosa attained peak in 40th SMW in all genotypes (in AL 1747: 39th SMW). Population varied from 0.08-0.20 nymph/plant and 0.20-3.69 adult/plant during period of study. M. obtusa persisted from 41st SMW to 48th SMW and reached it’s peak in 45th SMW. Empoasca kerri nymphs persisted from 29th SMW to 43rd SMW (AL 1747: 44th SMW) with peak in 33rd SMW. Pod damage (%) by M. vitrata, H. armigera, C. gibbosa and M. obtusa was reported as 2.10, 4.03, 25.16 and 2.31%, respectively. Grain yield of different genotypes ranged from 775-1200 kg/ha. Significant and negative correlation was found between H. armigera and minimum temperature, evening relative humidity, average relative humidity, wind speed and rainfall. Nymphal population of C. gibbosa exhibited significant and negative correlation with temperature, wind speed, while adults showed significant and negative correlation with relative humidity (Eve. and Avg.). E. kerri population exhibited significant and positive correlation with temperature (minimum and maximum), however, M. obtusa population showed significant and negative correlation with temperature, relative humidity (avg. and eve.) and wind speed. Genotypes evaluation studies showed minimum pod damage in AH 9-18 (for M. vitrata, H. armigera and M. obtusa), AH 16-02, B-17200, H 00-15 (for H. armigera). Grain yield ranged from 777.78 kg/ha (Paras) to 1859.26 kg/ha (AH 9-18). Evaluation of insecticides against pod borer complex indicated spinosad 45 SC as most effective against M. vitrata, H. armigera and M. obtusa. Spinosad 45 SC was found at par with indoxacarb 14.5 SC (M. vitrata and H. armigera), chlorantraniliprole 9.3 + lambda-cyhalothrin 4.6% ZC, lambda-cyhalothrin 5 EC, emamectin benzoate 5 SG and deltamtherin 2.8 EC (H. armigera) and azadirachtin 0.03% (M. obtusa). Maximum grain yield was obtained in spinosad 45 SC (919.26 kg/ha) sprayed plot.
Open Access
Studies on insecticide use pattern, population susceptibility and insecticide evaluation against Amrasca biguttula biguttula (Ishida) in cotton
(CCSHAU, Hisar, 2020-08) Pritam Kumari; Anil
A survey was carried out to study the insecticide use pattern in Sirsa, Hisar and Bhiwani districts of Haryana during kharif, 2019. The maximum respondents (70.00%) were found to be belonging to the age group of 40-60 years. Education status of farmers was quite good with an overall literacy rate of 87.00% and 56.00% of the respondents were having more than 15 years of experience in cotton cultivation. Most commonly grown Bt cotton hybrid by the majority of farmers (34%) was RCH 773 BG II followed by RCH 776 BG II (31.30%), US 51 BG II (13.30%), Ankur 3028 BG II (13.30%) and US 81 BG II (8.00%). Based on farmers experience, whitefly, Bemisia tabaci and leafhopper, Amrasca biguttula biguttula were the most important pests among sucking pests in Bt cotton. All the farmers were found to target whitefly and leafhopper for control whereas in case of dusky cotton and red cotton bug none was reported to targeting for control. The incidence, severity and yield losses of sucking pests especially whitefly and leafhopper were estimated to be high by 100, 86.67 & 82.70; 76.67, 74.00 & 64.67% farmers, respectively. The cent per cent farmers was found to adopt control measures at 61-90 days after sowing as highest pest incidence was estimated by cent per cent farmers at this duration. The majority of the farmers (44.67%) were found to be dependant on Agriculture input dealers for information in cotton cultivation followed by CCS HAU Hisar/CICR-RS (34.66%). Major constraints faced by farmers in insect pest management were high cost of pesticides, weather problems and lack of knowledge about bioagent and insubstantial control or poor efficacy of insecticides. Insecticides like imidacloprid, thiamethoxam, emamectin benzoate, fipronil, dimethoate and monocrotophos were mainly used by farmers to control sucking pests. Besides, newer insecticides like flonicamid, dinotefuran, diafenthiuron, spiromesifen and spinetoram were also being used by farmers. Insecticide-bioassays were carried out to assess the susceptibility of field-collected cotton leafhopper from Hisar, Sirsa and Bhiwani districts to commercial formulations of imidacloprid 17.8% SL, thiamethoxam 25% WG and flonicamid 50% WG during kharif, 2019. Intrinsic toxicity data on imidacloprid 17.8% SL, thiamethoxam 25% WG and flonicamid 50% WG indicated that Bhiwani population was most susceptible to these insecticides with LC50 values ranging from 7.23-24.74 ppm followed by Hisar population (10.09-29.83 ppm) whereas Sirsa population was found to be least susceptible with LC50 values of 12.17-34.60 ppm. Among different insecticides, flonicamid 50% WG with LC50 values ranging from 7.23 to 12.17 ppm showed maximum toxicity followed by thiamethoxam 25% WG 20.73 to 29.60 ppm while imidacloprid 17.8% SL was found to be least toxic insecticide with LC50 ranging from 24.74 to 34.60 ppm. Based on mean of two sprays in a field trial during kharif, 2019, the lowest mean nymhal and adults population (No. per 3 leaves) were recorded in flonicamid 50% WG @ 150 g ha-1 (0.84 nymphs and 1.73 adults) followed by dinotefuran 20% SG @ 150 g ha-1 (1.49 nymphs and 2.06 adults) and diafenthiuron 50% WP @ 500 g ha-1 (1.65 nymphs and 2.25 adults). Imidacloprid 17.8% SL @ 100 ml ha-1, thiacloprid 21.7% SC @ 125 ml ha-1, thiamethoxam 25% WG @ 100 g ha-1 and buprofezin 25% SC @ 1000 ml ha-1 were found to be moderately effective insecticides. Monocrotophos 36% SL @ 437 ml ha-1 was found to be the least effective insecticide. The non-significant differences were observed in the population of natural enemies (spiders, coccinellids & Chysoperla) among the different treatments. The highest seed cotton yield (q ha-1) was obtained with flonicamid (21.60), followed by dinotefuran (20.99), diafenthiuron (20.71), imidacloprid (20.41), thiacloprid (20.12), buprofezin (19.87), thiamethoxam (19.83) and monocrotophos (19.37). On the basis of cost of protection, the incremental cost benefit ratio was maximum with imidacloprid (1:6.36) followed by thiacloprid (1:5.64), thiamethoxam (1:5.29), monocrotophos (1:4.74), dinotefuran (1:4.38), flonicamid (1:3.99) and buprofezin (1:3.86).

Theses

Browse

Thesis Type

Type

Author

Date

Subject

Search Results