| The discovery of Photo-Sensitive Genie Male Sterile (PSGMS) rice provides a preferable way for the utilization of heterosis in rice, and enriches the theoretical studies on the regulation of plant growth and development. The rolB gene from Agrobacterium rhizogenes can stimulate the formation of roots and other growth alterations in transgenic plants with auxin-like effects. This project was aimed to investigate the effects of endogenous hormones on the fertility expression of PSGMS rice, and explore the practical potentials of rolB in plant-shape improvement of rice by transforming Nongken58S with rolB driven by CaMV35S promoter (CaMVBT) and its own natural promoter, respectively. Systematic studies were performed on the molecular detection, morphological and fertility observations, endogenous hormone and other related physiological property determinations, etc. The main results are as follows:1. rolB transgenic Nongken58S plants were obtained for the first time by Agrobacterium-medmted transformation. Southern blot analyses confirmed that 56 transgenic plants were transformed by P35S-rolB and 25 by PB1100-rolB constructs.2. The pronounced changes were observed in morphology of transgenic plants, and the alteration varies along with the use of different promoter.1) CaMVBT transgenic plants showed obviously morphological abnormalities compared with regenerants from untransformed tissues and original materials. 53.6% of TO transgenic plants did not grow normally and showed stunted plant and extremely poor growth-potential, fewer tillers, smaller and rolled or wrinkled leaves, twisted spike-stalk, deteriorated spikelets and flower organs, absolute abortion under different conditions, or even necrotic tissues in some plants. While, some other TO transgenic plants (46.4%) grew normally and set a few seeds, but showed signs of plants with excessive auxin level over normally physiological extent, which resulted in dwarf and bushy shape with more tillers and decreased apical dominance, and reduced sizes of leaf, spike and spikelet, fewer differentiated spikelets, and rolled or wrinkled leaves in some plants. Morphological observations in this study indicated that most phenotypical alterations in CaMVBT transgenic rice were surprisingly similar to those previously reported in dicotyledon plants. T1 and T2 progeny plants also showed similar morphological changes as their TO parents did. The height of T2 transgenic plants is only 61.6% and 68.0% of that of original and regenerant control, but number of tillers per plant increased by 39.4% and 36.9% over these two controls respectively.2) Most of regenerated plants and their progenies transformed with rolB driven by natural promoter displayed rolB effects in maintaining apical dominance with upright and compact plant shape, fewer tillers, lower height, dark-green leaves due to increased chlorophyll content, denser caryopsis setting density. While, some other TO plants showed smaller stature, thinner stem, rolled leaves, poorly growing potential and pollen sterility even under short-day, which were largely similar to those observed in some CaMVBTtransgenic plants. Although most TO plants and their progenies showed less value of practical usage due to the reduced sizes of leaf, grain, and etc, some progeny lines were still found with improved plant-shape and less variabilities in other traits.3. Introduction of rolB prominently changed the male-sterility of Nongken58S under long-day condition.1) Of the TO CaMVBT transgenic plants, the normally-growing plants showed two kinds of pollen fertility and seed-setting ratio under long-day condition. 62.9% of which showed poorer pollen fertility, smaller, thinner seeds than those of untransformed regenerant control and that seeds were nonviable. While, the other parts showed that the percentage of fertile pollen was as twice as that of control, but had lower seed setting, smaller grain and lower seed germination ratio. The male fertility of progeny lines from the latter increased distinctly under long-d...
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