GOWDA, BASAVEM, RADHAKRISHNA MAIYA2019-10-152019-10-151999No . of references 154http://krishikosh.egranth.ac.in/handle/1/5810131221Investigations on standardisation of isolation distance, effect of foliar spray of chemicals and stages of picking on seed yield and quality and standardisation of sieve size for seed grading of naturally coloured cotton genotype, DDCC-1 were carried out at Agricultural Research Station, Dharwad during the year 1998-99. The studies on isolation distance indicated that a distance of 7 m from colour cotton plots is found to be sufficient to produce genetically pure seeds. Results of foliar spray of chemicals indicated that, spraying of DAP @ 2% had resulted m significantly highest plant height, sympodial branches and number of bolls per plant followed by NAA (20 ppm) and cytozyme (0.1%). Foliar spraying of NAA significantly increased the seed yield followed by DAP, cytozyme and CUSO4. Spraying of growth regulators and nutrients also significantly influenced the seed quality parameters. Significantly higher germination, shoot length, root length, field emergence and vigour index were observed in plants sprayed with NAA followed by cytozyme and DAP. The stages of picking showed significant influence on number of bolls harvested per plant, mean boll weight, seed index and number of seeds per boll and seed weight. All these parameters were significantly higher in first picking followed by second and third picking and nearly 89.0 per cent of seed yield was contributed by the first two pickings. Picking stages were significantly influenced the seed quality parameters. In general, first picking seeds recorded significantly higher germination, field emergence, root and shoot length and seedling vigour compared to second and third picking seeds. The studies on size grading indicated that, seed grading with 4.75 mm (R) sieve gave higher seed recovery (86.75%), germination (82.04%), field emergence (65.0%)), root length (12.63 cm), shoot length (8.78 cm) and seedling vigour index (1752).ennullThesis