Identification and classification of the green tea varieties [Thea sinensis] by the morphological characters of flower organs

The flower organs of tea plants show a very wide variation. Accordingly, the morphological characters of the flower organs had been investigated and the variance components of years, varieties and sampled flowers were estimated for the purpose of identification of tea varieties. As a result, a new method of the expression of types of flower organs has been proposed. Characters of pistil showed the distinct variation among the varieties. Large variances among years were also observed in flower size, length of pistil (b+c), and length of un-splitting part of style (a). Heritabilities in broad sense were estimated to be 0.460 in flower size, 0.342 in number of petals, 0.044 in number of style arms, and 0.846 in splitting degree of style arm, respectively. Three characters of pistil having not only large variances among varieties but small ones among years were used in the classification of 48 green tea varieties. Each character was coded as follows: First, the capital letter (L, M or S ; long, equal or short) indicates the relative length of pistil to stamens. Secondly, the small letter (s, m or d ; shallow, medium or deep) expresses the splitting degree of style arm (a/(b+c)) and lastly the dush (", ' or empty ; distinct, obscure or no) which is set at the second letter's shoulder denotes the constriction of style arm. For instance, Yabukita, Okumidori and Yutakamidori could be coded as Sd, Lm" and Lm', respectively. By this method, the three groups of varieties which have been sometimes confused could be clearly discriminated, respectively. Therefore, the flower type coding by using the three pistil characters was confirmed to be very effective for identification of the tea varieties.