Abstract
Cytogenetical studies on the amphidiploids raised from interspecific hybrids of Quamoclit by the colchicine treatment have been carried out by the author.
In amphidiploids, the length of guard cells of stomata is larger than that of the parents, and about as large as that of Q. Sloteri (Table 3).
Further, the size of flowers is larger than that of the parents (Fig. 2).
In F1 plants, abortive pollen grains were observed in exceedingly higher percentage than in amphidiploids (Table 5). The size of pollen grains in amphidiploids is larger than that of the F1 (Table 6), i. e., nearly equal in size to the Q. Sloteri's.
F1 plants were completely sterile, but the amphidiploids were fertile, though the percentage is low (16.04%).
The fruits of amphidiploids were morphologically intermediate between parents of them.
The weight of 1000 seeds of Q. coccinea, Q, coccinea var. hederifolia and Q. pennata were 11.6, 14.2 and 16.5grs respectively. And that of the amphidiploids from hybrid I and II were 30.1 and 32.6grs, that is nearly equal to the seed weight of Q. Sloteri, 31.6grs.
The number of somatic chromosomes were 30 in Q. pennata (Fig. 7). 28 in both Q. coccinea and Q. coccinea var. hederifolia (Figs. 5 and 6). In F1 plants of Q. coccinea×Q. pennata and Q. coccinea var. hederifolia×Q. pennata, the number of chromosomes was 2n=29 (Figs. 8 and 9) in both cases. The number of chromosomes of amphidiploids raised from hybrid I (Q. coccinea×Q. pennata) and II (Q. coccinea var. hederifolia×Q. pennata) was 2n=58 in both combinations (Fig. 10). These numbers correspond to double the somatic number of F1 of hybrids I and II, viz. equal to the number of Q. Sloteri's chromosomes 2n=58 (Fig. 11).
