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Senna spectabilis (DC.) H.S.Irwin & Barneby is an invasive tree species native to tropical America and is commonly found in the forest areas of Wayanad Wildlife Sanctuary. Its aggressive growth rate and ability to quickly cover up open and degraded lands in forest ecosystems make it challenging to control its spread. Reproductive studies of S. spectabilis and its pollen-ovule ratio indicate this species is cross-pollinating. The species is self-compatible, owing to the simultaneous occurrence of xenogamy, geitonogamy and autogamy. This reproductive strategy helps the taxon to colonise degraded areas and invade the forest ecosystem. The anthesis is diurnal and sometimes asynchronous. Peak insect visitors were observed from 0900 h to 1230 h, with the major visitor being Tetragonula iridipennis. Xylocopa violaceae was also a regular visitor along with resident Formicidae members, such as Oecophylla smaragdina and Myrmicaria brunnae. They feed on the floral parts, like tender petals and sepals. The reproductive syndrome of this plant favours maximum fertilization. [ABSTRACT FROM AUTHOR]

Senna spectabilis is an invasive alien species known for its extremely fast-growing habit, profusely flowering and fruit setting nature, and high coppicing ability. In India, its introduction is not well documented, which probably may have been introduced as an ornamental plant. Presently this species has aggressively spread across the moist deciduous forests of Wayanad wildlife sanctuary in the Western Ghats, peninsular India, with adverse impact on the survival of the indigenous species of flora and fauna. The present study used six distinct populations of the species, Anakkatty, Muthanga, Vythiri, Azhnjilam, Thiruvanathapuram and Munnar karyotype analysis. In mitotic metaphase, cells of S. spectabilis showed a stable chromosome count of 2n = 28, x =14. The statistical analysis shows that there was a significant difference between the characters studied. The observations were compared with the chromosome characters reported from native S. spectabilis population. While it was found that the chromosome number remainsthe same 2n = 28, there were differences with most of the characters studied. The study points to the requirement for more intense taxonomic studies and monitoring of this species and its populations. [ABSTRACT FROM AUTHOR]

Big leaf mahogany (Swietenia macrophylla, King) is a valuable Neotropic timber species. It is the first extensively traded timber species to be listed in Appendix II of the CITES in 2002. The tree was introduced to India in 1795 and Kerala in 1872. The present study aimed at selecting plus trees of Swietenia macrophylla and evaluating their genetic variability. Forty-five plus trees were selected from 593 candidate trees spread over fifteen locations in Kerala based on baseline regression of trunk volume to crown volume, followed by scoring for qualitative characters. The clean bole height, GBH, crown width, crown volume and wood density of CPTs ranged from 6 to 13.4 m, 0.75 to 2.00 m, 8 to 15 m, 7 to 16 m and 21 to 23 mm, respectively. The plus trees were grouped into five clusters based on their quantitative and qualitative characters. Clustering was independent of the geographical location indicating a lack of development of any land races in the species [ABSTRACT FROM AUTHOR]

A reconnaissance survey was conducted in Southern Western Ghats, India to identify the wild populations of Terminalia paniculata. From the explorative survey, 16 natural populations from different localities of the study area were identified. Collected 36 fruits from each tree and fruit trait quantification of total 3456 fruits (36 x 16 x 6) from 16 populations were used for the study. Hierarchical clustering of selected populations and correlations among fruit traits and between tree traits and fruit traits visualised using a dendrogram. The results indicated significant differences in fruit traits like fruit fresh mass, fruit large wing length and fruit large wing width. Clustering of fruit characters for all the accessions revealed the genetic relatedness between accessions. It reveals that selected populations of T. paniculata belong to two major clusters and confirms that 16 populations are either adjacent or distant in-terms of fruit traits are independent of the geographical station. The relationship between fruit traits indicates a significant positive correlation between fruit traits ranging from 0.352 to 0.739. Even though fruit traits show significant correlation within, a non-significant and very week correlation was obtained with tree stand-up traits except tree girth with fruit large wing length (21.4%). [ABSTRACT FROM AUTHOR]

Terminalia paniculata is one of the commercially important timber tree species commonly distributed in Kerala and Karnataka region of Peninsular India and mainly used for timber, tannin, fodder products, folk medicine, Ayurvedic treatments and opium poisoning. Natural populations are declining due to high seed emptiness, poor regeneration status and anthropogenic activities such as habitat fragmentation, land conversion and over-exploitation. The timber is superior in quality and mainly used for making beams, rafters, battens and for similar work. The present article focuses on population, regeneration, wood characteristics and economic, ecological, phytochemical and pharmacognostic importance of T. paniculata and this will provide comprehensive information for further research. [ABSTRACT FROM AUTHOR]

Teak (Tectona grandis L.f.) is the well-known tropical timber species to meet the demand of wood-based industries. Choosing superior parents and developing technologies for its vegetative propagation is essential for promising better growth and yield. Production of epicormic shoots on live detached branches under high humidity and temperature, is an excellent propagation option widely practiced in trees. The present study was designed to investigate the effect of genotype on the development of epicormic shoots from branch cuttings and its rooting behavior. Epicormic shoot and root production was observed to vary significantly among the genotypes studied. Initiation of bud burst started from the 5th day and continued till the 9th day of planting. The number of epicormic shoots produced too significantly varied among the genotypes. The maximum number of epicormic shoots was observed in genotypes Aravallikkavu,Topslip-6, Nellikutha-2, and Nellikutha-7, whereas Nedumkayam-1 produced one or no shoots. The average shoot diameter from different genotypes varied from 2.85 cm to 5.43 cm. Significant variation among the genotypes in rooting was observed. The highest rooting percentage of epicormic shoots was recorded in the Nellikutha-3 genotype (57.11 %) followed by Tholpatti 01 (47.89 %) and Mananthavadi 02 (39.11 %). The present study confirms the genotypic influence on vegetative propagation by varied shoot and root production potential. [ABSTRACT FROM AUTHOR]