Relationship Between the Shape of Silica Body from Motor Cells and Morphological and Physiological Characters of Grain for the Discriminations of indica and japonica Rice in China.

Abstract

Methods of discrimination of indica and japonica rice based on the shape of silica body from motor cells in the leaf blade and on morphological and physiological characters of grain were compared, and their relationship was investigated. Fifty Chinese native and improved rice varieties (25 Hsien and 25 Keng) were used. Four morphological characters of silica body from the motor cells (vertical length, VL; horizontal length, HL; lateral length, LL and shape coefficient b/a) (Fig. 1) , grain shape (length, L; width, W and their ratio L/W), apiculus hair length (AH), phenol reaction of the hull (PR) and potassium chlorate (KClO-3) resistance of seedlings (KC) based on injury scores (0 to 3) were analysed. Based on the above characters of indica and japonica cultivars defined by Sato's discriminant function (Z (SD) =PR+1.313KC-0.82AH-1.251) (Table 1 and Fig. 2), discrimination analysis were carried out, and discriminant functions were developed. Effectiveness of the different functions was compared. The probability of correct discrimination based on the shape of the silica body was 92% (Table 2 and Fig. 3), a value higher than that based on the grain shape (74%) (Table 2 and Fig. 4), and almost the same as the values based on the phenol reaction (92%) and resistance to KClO-3 (98%). The discrimination results based on the shape of the silica body were strongly correlated with those obtained by the Sato's discriminant function (Table 3 and Fig. 5), which may be ascribed to the close relationship between the morphological characters of the silica body and the phenol reaction of the hull and resistance to KClO-3 of seedlings (Table 4). For studies of the origin and dissemination of rice due to the stability of plant opal, discrimination of indica and japonica rice based on the shape of plant opal is more suitable than that based on the shape of carbonized rice.