PATEL, B. K.PATEL, J. S.2018-06-042018-06-041988http://krishikosh.egranth.ac.in/handle/1/5810049001With a view to finding out the influence of different levels of Zinc on the yield , quality and chemical composition as well as smoke characteristics of bidi tobacco cv GT 5 and nutrient status after the harvest of crop, an experiment was undertaken at Bidi Tobacco Research Station , Gujarat Agricultural University, Anand Campus, Anand during the year 1986-87. The experiment consisted of four levels of Zinc, namely no Zinc (Zn0), 2.5 ppm (Zn1), 5 ppm (Zn2) and 7.5 ppm (Zn3) Zn. Zinc was applied inform of Zinc sulphate. The experiment was conducted in a randomised block design with six replications . The observations on yield and its attributes, spangle score, valuation and monetary returns were recorded. The net returns were also computed. The samples of leaf lamina, midrib, stalk and suckers were analysed for various chemical constituents and uptake of major, secondary and micronutrients was worked out. Bidis prepared out of the produce from different treatments were subjected to smoke analysis. Soil samples collected upto 15 cm depth after the harvest of the crop were analysed for major and micronutrient cations. Though yield differences were non-significant due to Zn application, Zn2 (5 Ppm Zn) treatment produced highest cured leaf and fetched the highest price of its produce thereby earning maximum gross realization. Cost : benefit analysis based on the price of Zn application showed that Zn1 and Zn2 treatments were comparable. Data on the chemical composition revealed that nitrogen, nicotine and reducing sugars contents were not significantly modified by Zn application. The content and uptake of N, K, Ca, Mg and Cu as well as their total uptake remained significantly unaltered due to different treatments . Phosphorus content of lamina was significantly changed by Zn application, wherein minimum P2O5 conxent (0.65 %) was recorded at the highest (Zn,) level of applied Zn, Indicating Zn-P antagonism at the higher levels of applied Zn. Sulphur content and uptake were significantly affected by Zn application in case of midrib.In general C1, Fe and Mn contents and uptake data showed synergistic relationship with Zn application. Zinc content of all the plant parts and the total uptake of Zn showed significant differences due to Zn application. Zn content and uptake increased as the rate of its application increased. Total particulate matter (TPM), CO, and smoke nicotine were minimum and number of puffs were maximum under Zn3 treatment, which showed significant differences due to Zn application. None of the major and micronutrients except Zn were significantly changed by Zn incorporation into soil. Zn application steadily increased available Zn status of soil . Above findings suggest that Zn application in a zinc deficient (0.45 Ppm Zn) loamy sand soil of Anand requires Zn supplementation for the improvement of yield and quality. Besides this Zn application at higher rates ( 5 and 7.5 Ppm Zn) has helped in reducing smoke toxicants, which has opened up new horizons for making bidi safer smoking product. However, these findings need to be confirmed by further experimentation before making any valid recommendation.enAgricultural Chemistry and Soil ScienceA StudyThesis