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Lalita Mahantagouda Patil Hosakatte Niranjana Murthy Vijayalaxmi S. Dandin Sunita P. Koli Shirugumbi Hanamanthagouda Manohar Shivanand D. Payamalle 《林业研究》2016,27(1):161-165
We developed a method for in vitro regeneration of Garcinia xanthochymus(yellow mangosteen) from matured seed segments. Multiple shoots were induced on woody plant(WP) medium supplemented with cytokinins.An average of 11 shoots per explant were regenerated from mature seed segments on WP medium containing 20 μM 6-benzylaminopurine. Histological analysis revealed that hypodermal cells of seed segments were initially involved in active division, which later developed into meristemoids, subsequently leading to the formation of shoot buds.Shoot elongation was achieved by repeated subculturing of seed explants in shoot regeneration medium. Rooting of shoots was achieved on WP medium supplemented with indole-3-butyric acid or a-naphthalene acetic acid. Plantlets were transplanted to pots containing soil: compost(1:1) and survival rate was 90%. 相似文献
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Agricultural fallows, village commons and degraded forests, serve as important common community property resources throughout India, but due to their degraded status they are considered as ‘wastelands’, having little economic value and poor biodiversity. A study on secondary succession was conducted in agricultural fallows around Puducherry, India to review the negative image of ‘wastelands’. Chronosequences of four sites aged 2, 4, 10 and 50 years were used to investigate change in species composition and abundance, convergence with a nearby forest and to examine their economic use. A comparison of life‐forms, species richness and diversity indices showed that herbaceous species dominated up to 10th year sere, from which point in succession, woody species became more common. It was in the 50th year sere that shrubs and secondary tree species occurring in nucleated clumps became dominant. A cluster analysis based on Bray–Curtis similarity index shows a sequential development of vegetation through time, though 50th year plots showed no convergence with the Tropical dry evergreen forest (TDEF), but the principal component analysis demonstrates a change in community structure from grasslands to shrub and secondary tree species' dominance. Presence of adults of five primary forest species found in the clumps indicates a fast rate of secondary succession, considering that grazing and resource removal occurred in the sites. The potential value of the ‘wastelands’ is evident from the fact that 64 per cent of recorded species have economic use, which underlines the need for their sustainable utilization for better management of bioresources rather than converting them into monocultures. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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The present investigation was conducted to elucidate the influence of an opioid peptide, leucine-enkephalin (L-ENK), on the reproductive axis of the tilapia Oreochromis mossambicus. In the first experiment, administration (i.p.) of 25, 100, and 300 μg L-ENK to the stripped female tilapia, for a period of 22 days, resulted in a significantly higher number of stage I follicles compared to those of initial controls and experimental controls, whereas the mean number of stage II and III follicles and serum levels of E2 did not significantly differ among different experimental groups. A significant increase in the number of stage V (fully ripened) follicles was concomitant with significant reduction in the follicular diameter in 25 or 100 μg L-ENK-treated fish compared to those of experimental controls. However, significant reduction in the mean number and diameter of these follicles was observed in 300 μg L-ENK-treated fish compared to those of experimental controls and 25 or 100 μg L-ENK-treated fish. In the second experiment, the stimulatory effect of 25 μg L-ENK on the ovary was abolished in combination with gonadotropin-releasing hormone antagonist (GnRH-A). In conclusion, these results suggest that L-ENK exerts stimulatory as well as inhibitory effects on the ovary in a dose-dependent manner, and that these effects are possibly mediated through the GnRH, for the first time in fish. 相似文献
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