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ThesisItem Open Access Bio-ecology and chemical control of citrus psylla, Diaphorina citri Kuwayama on sweet orange(CCSHAU, 2017) Naveen Vikram Singh; Yadav, G.S.The study on “Bio-ecology and chemical control of citrus psylla, Diaphorina citri Kuwayama on sweet orange” was conducted with the following objectives: (1) Study on biology of citrus psylla on sweet orange. (2) Population dynamics of citrus psylla on sweet orange in relation to environmental variables. (3) Evaluation of different insecticides against citrus psylla. (4) Estimation of residue of some insecticides in sweet orange. The present study was conducted at the Screen house, Research Area of Department of Horticulture and Pesticide Residue Laboratory, Department of Entomology, CCS Haryana Agricultural University, Hisar during the year 2014 and 2015. A single female laid an average of 505.2 ± 26.8 eggs which hatched in 3.5 ± 0.24 days. The mean duration of first, second, third, fourth and fifth nymphal instars were 2.6 ± 0.25, 3.0 ± 0.18, 4.5 ± 0.21, 4.9 ± 0.22 and 4.7 ± 0.22 days, respectively. The mean longevity was 33.2 ± 0.75 days for female and 28.6 ± 0.52 days for male. Two population peaks of nymphs were observed, first in April-May and second in August- September. Highest population of adults was found during May. With the decrease in temperature from the end of September, the population of D. citri started to decrease and reached its lowest level during winter season. Correlation analysis indicated that maximum and minimum temperature, sunshine and rainfall were positively correlated with nymphal, adult and cumulative population but the effect of rainfall on adult population was non-significant, while relative humidity was negatively correlated. The per cent reduction in nymphal population was recorded to be highest in imidacloprid 200 SL i.e., 68.9 and 67.1 % & 70.2 and 71.0 % after first and second spray and lowest in NSKE 5% i.e., 41.3 and 41.4 & 43.3 and 42.4 % respectively, during 2014 &2015. The average residues of dimethoate and imidacloprid in rind of sweet orange at recommended dose were 0.114 and 0.678 mg kg-1, respectively, whereas the corresponding residues in pulp was 0.154 and 0.063 mg kg-1. The residue reached below detectable level in 10 days in case of dimethoate while in imidacloprid it was 0.15 mg kg-1 in rind of sweet orange whereas, it was below detectable level in pulp. The washing of sweet orange reduced residues of both the insecticides from 73.9 -100% in/on 0 day samples.ThesisItem Open Access Colony productivity and honey quality of Apis mellifera L. in relation to colony strength and extraction frequency(CCSHAU, 2017) Saini, Sumit; Chaudhary, O.P.The studies on colony productivity and honey quality of Apis mellifera L. in relation to colony strength and honey extraction frequency was conducted in Hisar area. Honey bee colonies were initially maintained at 3 strengths of 5, 10 and 15 frames/colony and superimposed with three honey extraction frequencies i.e. regular (farmer‟s practice), two and one extraction. During honey flow season on mustard, superiority of 15 frame colonies over 10 and 5 frame strength was crystal clear as 5 frame colonies recorded minimum sealed honey area (108.5 inches2/colony) that increased significantly in 10 frame (246.9) to become maximum in strongest 15 frame colonies (402.9), a 3.7 fold increase over 5 frame colonies. Under regular honey extraction regime, minimum sealed honey (149.1 inches2) was observed that increased significantly in 2 extractions (265.1) and was maximum (345.1) when honey was extracted only once in a season. Similar trend for brood, eggs, pollen and drone area were also recorded. The 5 frame colonies finally grew to 11.3 frames, 10 frames to 15.1 and 15 frame colonies attained 20.7 frames/colony. Colony growth in absolute terms was maximum (2.24 times) in weakest colonies, decreased (1.51 times) in medium and was minimum (1.38 fold) in 15 frame colonies. Honey production is direct product of colony strength as in all extraction regimes, strongest colonies produced maximum honey followed by 10 and 5 frames. Maximum honey was produced in 15 frame colonies under single extraction (27.16 kg/colony) followed two extractions (24.11) and single extraction in 10 frame colonies (22.98) and least in farmer‟s practice (12.46 kg). Quality of honeys produced in different treatments confirmed to BIS/FSSAI and even international norms and results for all quality parameters were remarkable under single and two honey extractions over regular extractions. During dearth period, sealed honey area was proportional to the colony strength and maximum in 15 frame colonies (140.4 inches2), decreased in medium strength (99.7) and was lowest (30.6) in weakest colonies. Results signify higher reserves despite maximum consumption in strongest colonies than lower strength colonies. Total brood was minimum (83.5 inches2) in weakest colonies, increased (156.3) in 10 frame (1.9 folds) to become maximum (215.1) in 15 frame colonies (2.6 fold increase over weakest colonies). Colony weight was maximum (7.3 kg/colony) in strongest colonies followed by 10 frames (5.5) and least in 5 frames, merely 2.2 kg. A constant decrease in weight was recorded from June (6.4 kg) till end October (3.8 kg). Pollen forager ratio (PFR) in 10 frame colonies was maximum (53.8%) and lower in 5 and 15 frame colonies (48.6 and 49.7%) in 2015-16 while trend was reverse during 2014-15. Overall performance of colonies during dearth was influenced by initial colony strength as colonies on 5 and 15 frames lost maximum strength (50 and 54.4% combs) than 10 frame colonies (28.3%). Maximum colonies of 5 frames perished (41.7%) followed by strongest (30.0%) but all 10 frame colonies survived dearth successfully. Total sugar consumption was maximum in 5 frame colonies (27 kg), lower in 10 frames (14 kg) while 15 frame colonies needed only 10.5 kg sugar due to reserves. It is economical to keep colonies at initial strength of 10 frames during dearth period.