19.Grey tobacco
工業(yè)科技

        One subject of interest is “grey” flue - cured tobacco. Despitemany studies from different countries,there is no conclusive,unifiedanswer. Among the factors suspected to be associated with “grey” tobacco,are: soil pH,organic matter,maturity at harvesting,......（本文共 1831 字）     [閱讀本文] >>