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2012 - 20162
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Subject: Entomology × Author: Sandeep Singh × End date: 2019 ×
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    Development and management of fruit flies, Bactrocera spp. on different fruit crops
    (PAU, 2012) Sandeep Singh; SHARMA, D. R.
    The present study entitled “Development and management of fruit flies, Bactrocera spp. on different fruit crops” was conducted inthe Fruit Entomology Laboratory, Department of Fruit Science, Punjab Agricultural University, Ludhiana and University Seed Farm, Ladhowal during 2010 and 2011. Studies on development of fruit flies, Bactrocera dorsalis (Hendel) and Bactrocera zonata (Saunders) on different fruit crops showed that guava was the most suitable host followed by Kinnow, pearand peach. Different combinations of temperature and relative humidity did not have any consistent influence on biological parameters. Evaluation of the impact of number of methyl eugenol based mineral water bottle traps (4-16 traps/acre) in male annihilation technique (MAT) in peach, pear, guava and Kinnow revealed that number of traps had a significant impact on the number of males trapped, quality marketable fruits and yield. Maximum males were trapped in guava followed by Kinnow, pear and peach. Four peaks were recorded with the availability of hosts like peach, pear, guava and Kinnow. A total of 1.99 lakh males were trapped (SMW 14 to 45) in these four crops during the year 2010. The present study indicated that availability of host plants had a direct bearing on population of fruit flies but the population was positively correlated with maximum and minimum temperature, whereas rainfall, sunshine and relative humidity had no significant effect on population variation on different crops. The successful control of male fruit flies and highest fruit yield was achieved by using 16 traps/acre in all these crops. Spinosad based bait application technique (BAT) comprising of a mixture of protein hydrolysate (0.1%) and spinosad (0.03%) was an appropriate treatment for the management of female fruit flies on pear and guava. Application of new IPM Module involving cultural practices, sanitation, MAT (16 traps/acre) and BAT (a mixture of protein hydrolysate (0.1%) and spinosad 0.03%) had successfully reduced the fruit fly population/infestation on pear, guava and Kinnow crops. Adults of parasitoid, Biosteres (Chilocaudatus) longicaudatus Ashmead emerged from fruit fly infested peach, pear, guava and Kinnow fruits.
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    ThesisItemOpen Access
    Characterization of resistance in barley against corn leaf aphid Rhopalosiphum maidis (Fitch)
    (Punjab Agricultural University, Ludhiana, 2016) Sandeep Singh; Jindal, Jawala
    To characterize resistance in barley against corn leaf aphid (CLA), Rhopalosiphum maidis (Fitch) the biological parameters of aphid, morphological/phenological and biochemical parameters of plants were studied on five resistant genotypes (BCU-2806, IC-434880, BCU-4507, BK-9816, CIHO-6264) and one susceptible genotype (PL-426). The prolonged developmental period (12.92±0.49 to15.08±0.55 days) and total life span (32.45 ±0.77 to 33.82±0.76 days); and reduce fecundity (31.10±0.51 to 37.50±0.41 nymphs/female) and reproductive potential (2.24±0.06 to2.65±0.03 nymphs/female/day) were observed in resistant genotypes as compared to susceptible genotype PL-426 (12.07±0.34 days, 27.13 ±0.65 days, 42.20±1.48 nymphs/female and 3.75±0.13 nymphs/female/day, respectively). The morphological parameters viz. lower chlorophyll content (r=0.59), more numbers of tillers per meter row length (r =-0.94) and longer ear head size (r=-0.61) had significantly contributed towards resistance reaction in test genotypes. Among biochemical constituents, high total phenol content (r=-0.34), more specific activity of phenyal ammonia lyase (PAL) (r=-0.80) and polyphenol oxidase (PPO) (r=-0.36) had contributed towards resistance to CLA. However, higher total sugars (r=0.56), total soluble protein (r=0.60) and free amino acid content (r=0.47) had contributed towards susceptibility of test barley genotypes to CLA. In correspondence to these parameters, the genotype BCU-2806 and IC-434880 were resistant, while BK-9816, BCU-4507 and CIHO-6264 were moderately resistant and PL-426 was susceptible to CLA. Hence, the genotypes with lower sugar, protein, free amino acid and chlorophyll content and higher phenol content, specific activity of PAL and PPO and tillers/ meter row length with longer ear should be consider for breeding of resistance varieties in barley against R. maidis.