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University of Agricultural Sciences, Bengaluru

University of Agricultural Sciences Bangalore, a premier institution of agricultural education and research in the country, began as a small agricultural research farm in 1899 on 30 acres of land donated by Her Excellency Maharani Kempa Nanjammanni Vani Vilasa Sannidhiyavaru, the Regent of Mysore and appointed Dr. Lehmann, German Scientist to initiate research on soil crop response with a Laboratory in the Directorate of Agriculture. Later under the initiative of the Dewan of Mysore Sir M. Vishweshwaraiah, the Mysore Agriculture Residential School was established in 1913 at Hebbal which offered Licentiate in Agriculture and later offered a diploma programme in agriculture during 1920. The School was upgraded to Agriculture Collegein 1946 which offered four year degree programs in Agriculture. The Government of Mysore headed by Sri. S. Nijalingappa, the then Chief Minister, established the University of Agricultural Sciences on the pattern of Land Grant College system of USA and the University of Agricultural Sciences Act No. 22 was passed in Legislative Assembly in 1963. Dr. Zakir Hussain, the Vice President of India inaugurated the University on 21st August 1964.

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Subject: Sericulture × Author: CHANDRAKALA × Start date: 1970 × Type: Thesis × Thesis Type: Ph.D ×
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    GENETICS OF WHITE MUSCARDINE DISEASE RESISTANCE IN THERMOTOLERANT BIVOLTINE SILKWORMS (Bombyx mori L.)
    (University of Agricultural Sciences, Bangalore, 2022-12-18) CHANDRAKALA; MANJUNATH, GOWDA
    Three thermotolerant bivoltine silkworm breeds viz., B1, B4 and B8 were crossed with CSR4 to study the genetics of white muscardine disease resistance using six generation mean analysis and disease scoring using mean, geometric and hormonic productivity. The fifth instar silkworms were topically inoculated with muscardine fungus (9.04 × 104 spores / ml @ 0.5 ml per silkworm) and assessed. Cocoon, shell, pupal and filament weights showed high heritability (h2) and high genetic advance (GA) and larval duration, cocoon yield by weight, shell ratio, pupation rate and filament length showed high h2 and low GA both under normal condition and muscardine inoculation. Six generation mean analysis for the five quantitative traits viz., larval, cocoon, pupal and shell weights and shell ratio, revealed inadequacy of additive-dominance model indicating epistatic digenic interactions both under normal condition and muscardine inoculation. Duplicate-type epistasis played a greater role than complementary epistasis for all the five traits under normal condition. Under muscardine inoculation complementary epistatic gene action was observed for larval, cocoon and pupal weights. The magnitude of additive gene effects [d], additive genetic variance (σ2A), dominance gene effects [h] and dominance genetic variance (σ2D) under muscardine inoculation indicated significant epistatic gene action in controlling these traits. The disease scoring for B. bassiana infection revealed that B1 × CSR4 and B4 × CSR4 hybrids showed high resistance in terms of larval and shell weights and resistance in terms of cocoon weight and shell ratio implying they being resistant hybrids and among the parents, B1 and B4 showed resistance in terms of larval and shell weights and shell ratio while moderate resistance in terms of cocoon and pupal weights. Thus, B1 and B4 can be considered as muscardine disease resistant thermotolerant bivoltine silkworm breeds. Further, the genetic parameters revealed that, hybridization and selection in later generations may yield desired results to improve muscardine disease resistant in these breeds.