Cytology, morphology and pollen fertility of interspecific hybrids between Oryza sativa and O. officinalis.
1993
Alfonso A. | Villegas V.N. | Borromeo T.H.
UPL Ri3 was crossed with Oryza officinalis, a source of resistance against BPH [brown planthopper], GLH [green leafhopper] and WBPH [whitebacked planthopper]. Embryos were cultured in vitro resulting to several identical hybrid plants. F2 seeds were obtained from natural seed setting in F1 plants. These were germinated in vitro and grown in the greenhouse for evaluation. The present study aims to analyze the morphology, pollen fertility and cytology of the F1 and F2 plants. The F1 hybrids had semi-erect, grassy and vigorous growth. Like the wild parent, they had perennial life cycle, rigid awns, well exerted panicles, and purple stigma, auricles and basal leaf sheath. F2 plants resembled the F1's but these had soft-textured awns, moderately well-exserted panicles and longer anther, flagleaf, panicles, grain and culm. Variation in tillering ability, panicle type, grain size, and color of the leaves, basal leaf sheath, awn, apiculus and internode were noted among the F2 plants. Pollen fertility obtained from the F2's ranged from 0-0.45 percent, similar to 0.49 percent pollen fertility obtained from the F1's. A wide array of chromosomal aberrations were noted in the F1's and F2's. Among these are the occurrence of univalents, trivalents, laggards, bridges, early disjunction, non-congression, chromosome elimination and extra chromosomes.
显示更多 [+] 显示较少 [-]