Melia dubia Cav. of family Meliaceae is a fast growing, high value tree species native to India. Isolating DNA from matured dried leaves of M. dubia was difficult due to accumulation of secondary metabolites, majorly ...Melia dubia Cav. of family Meliaceae is a fast growing, high value tree species native to India. Isolating DNA from matured dried leaves of M. dubia was difficult due to accumulation of secondary metabolites, majorly polyphenolics, which resulted in dark brown to black colour of the pellet. In this study, a modified STE-(Sucrose, Tris-HCl and Ethylene Diamine Tetra Acetic Acid) CTAB (hexadecyltrimethylammonium bromide) method was standardized for removal of polyphenolics. The protocol developed yielded 200 - 1000 ng/μl of quality DNA without any impurities as evident by A260/280 ratio ranging from 1.75 - 2.0. It was also suitable for extracting quality DNA from other members of Meliaceae like Azadirachta indica and Melia azedarach. In downstream applications, the extracted DNA was used for PCR amplification by using ISSR and SSR markers. ISSR PCR conditions were optimized in a reaction volume of 25 μl, consisting of 30 ng of template DNA, 1.5 mM MgCl<sub>2</sub>, 200 μM of each of dNTPs and 2 U of Taq polymerase. The best amplification was observed and the same was applicable for SSR markers.展开更多
Canopy gaps play a significant role in maintaining structure and composition of tropical forests. This study was carried out in tropical evergreen forests of central Western Ghats in India to understand the influence ...Canopy gaps play a significant role in maintaining structure and composition of tropical forests. This study was carried out in tropical evergreen forests of central Western Ghats in India to understand the influence of canopy gap size and the relationship of gap regime attributes to diversity measures and regeneration. The average gap size in the study area was found to be 396 m2 and around half of gaps were 4–8 years old. Gaps created by natural single tree fall were smaller in size but significantly higher in number. Diversity and regeneration of woody species were compared with canopy gaps and intact vegetation. Species richness and diversity was higher in gaps than in intact vegetation. Macaranga peltata, a shade intolerant species dominated gaps while intact vegetation was dominated by shade tolerant Kingiodendron pinnatum.Gap size significantly influenced species diversity and regeneration. Gap area and age were significantly and negatively correlated with diversity measures but positively correlated with regeneration. Among all the attributes of gaps, regeneration was significantly positively correlated with light intensity. Gaps maintained species diversity and favored regeneration of woody species. In addition to gap size and age, other gap ecological attributes also affected species diversity and regeneration.展开更多
We compared morphological and genetic attributes of prog- eny obtained from three seed production areas （SPAs） and three corre- sponding unimproved stands （UIS） of teak （Tectona grandis L.f） at three broad teak ...We compared morphological and genetic attributes of prog- eny obtained from three seed production areas （SPAs） and three corre- sponding unimproved stands （UIS） of teak （Tectona grandis L.f） at three broad teak growing regions in the state of Karnataka, India. In general, seed morphological parameters such as seed weight, seed size and seed emptiness were significantly superior in SPAs compared to UISs. Seed germination percentage was also higher in seeds from SPAs. Seedling performance measured at two monthly intervals for six months was ob- served to be superior in SPAs at two of the three regions compared. Although the genetic diversity of progeny of SPAs was lower than UIS at all regions, the values were moderately high. Germination percent was positively correlated with fruit weight and kernel weight per seed, while diversity indices were negatively correlated with fruit weight, fruit di- ameter and kernel weight per seed. SPAs proved important as a source of moderately improved planting material with no severe threat to the ge- netic diversity of future plantations.展开更多
文摘Melia dubia Cav. of family Meliaceae is a fast growing, high value tree species native to India. Isolating DNA from matured dried leaves of M. dubia was difficult due to accumulation of secondary metabolites, majorly polyphenolics, which resulted in dark brown to black colour of the pellet. In this study, a modified STE-(Sucrose, Tris-HCl and Ethylene Diamine Tetra Acetic Acid) CTAB (hexadecyltrimethylammonium bromide) method was standardized for removal of polyphenolics. The protocol developed yielded 200 - 1000 ng/μl of quality DNA without any impurities as evident by A260/280 ratio ranging from 1.75 - 2.0. It was also suitable for extracting quality DNA from other members of Meliaceae like Azadirachta indica and Melia azedarach. In downstream applications, the extracted DNA was used for PCR amplification by using ISSR and SSR markers. ISSR PCR conditions were optimized in a reaction volume of 25 μl, consisting of 30 ng of template DNA, 1.5 mM MgCl<sub>2</sub>, 200 μM of each of dNTPs and 2 U of Taq polymerase. The best amplification was observed and the same was applicable for SSR markers.
基金funded by the National Remote Sensing Centre,Hyderabad,India under NRSC-DOS-DBTGovt.of India project entitled‘‘Biodiversity Characterization in Southern parts of Karnataka’’(Project Number:UAS(B)/DR/GOI/245/2011-12)
文摘Canopy gaps play a significant role in maintaining structure and composition of tropical forests. This study was carried out in tropical evergreen forests of central Western Ghats in India to understand the influence of canopy gap size and the relationship of gap regime attributes to diversity measures and regeneration. The average gap size in the study area was found to be 396 m2 and around half of gaps were 4–8 years old. Gaps created by natural single tree fall were smaller in size but significantly higher in number. Diversity and regeneration of woody species were compared with canopy gaps and intact vegetation. Species richness and diversity was higher in gaps than in intact vegetation. Macaranga peltata, a shade intolerant species dominated gaps while intact vegetation was dominated by shade tolerant Kingiodendron pinnatum.Gap size significantly influenced species diversity and regeneration. Gap area and age were significantly and negatively correlated with diversity measures but positively correlated with regeneration. Among all the attributes of gaps, regeneration was significantly positively correlated with light intensity. Gaps maintained species diversity and favored regeneration of woody species. In addition to gap size and age, other gap ecological attributes also affected species diversity and regeneration.
文摘We compared morphological and genetic attributes of prog- eny obtained from three seed production areas （SPAs） and three corre- sponding unimproved stands （UIS） of teak （Tectona grandis L.f） at three broad teak growing regions in the state of Karnataka, India. In general, seed morphological parameters such as seed weight, seed size and seed emptiness were significantly superior in SPAs compared to UISs. Seed germination percentage was also higher in seeds from SPAs. Seedling performance measured at two monthly intervals for six months was ob- served to be superior in SPAs at two of the three regions compared. Although the genetic diversity of progeny of SPAs was lower than UIS at all regions, the values were moderately high. Germination percent was positively correlated with fruit weight and kernel weight per seed, while diversity indices were negatively correlated with fruit weight, fruit di- ameter and kernel weight per seed. SPAs proved important as a source of moderately improved planting material with no severe threat to the ge- netic diversity of future plantations.
