On the Characteristics of Starch Contained in Various organs of Glutinous Rice Plants

Abstract

It is known that, in diploid glutinous rice plants, waxy or glutinous starch is found only in their pollens (of which chromosome number is 1 n) and the endosperms (3 n), while in all other parts (2 n), viz., leaf, stem, root and embryo etc., non-glutinous starch is found. In other words, it is said that waxy starch is seen only in the organs odd in chromosome number, and non-glutinous starch in the parts having chromosomes of even number, as far as the diploid plant is concerned. This experiment was carried out to make clear whether the relation above mentioned existed between the nature of starch and number of chromosomes in other polyploid glutinous rice plants or not. Tetraploid and diploid plants from each of three glutinous varieties and haploid plants from three varieties were used for materials. Main results were as follows : - (1) In all polyploid plants, all being of glutinous variety as shown in Table 1, waxy starch was found only in pollens and endosperms, and non-glutinous one was always found in all other parts, regardless of their number of chromosomes. Thus, the distribution of waxy starch appeared to have no regular connection with the chromosome number of plant parts. (2) Starch in the endosperms from both tetraploid and diploid plants possessed nearly the same ratio of amylose to amylopectin, as shown in Table 2, so that the constitution of the two kinds of starch seemed to be undistinguishable.