The main biodiversity crises of the new current millennium are extinction and species introduction. A species may be critically endangered and ultimately extinct when death rates exceed birth for a prolonged duration. The reasons may be either natural or anthropogenic. Nowadays, anthropogenic factors are prominent and cause the extinction of many species in the wild. To prevent the present problem conservation can be possible only through ex-situ methods. In the present study, six highly threatened species were selected for improving macro propagation techniques by using different seed germination methods. Seed germination response was best on by using mature soaked and scarified seeds. The preferable nutrient medium is a 1:1:1:1:1 ratio of red soil, black soil, cocopeat, sand and vermicompost. Through this study, we recorded good germination percentages with Boswellia ovalifoliolata 79%, Croton scabiosus 76%, Hildegardia populifolia 73%, Pterocarpus santalinus 71%, Shorea tumbuggaia 66%, Syzygium alternifolium 69%. These propagation methods are low cost and effectively worked and can be possible for restoration of species in their natural habitats through ex-situ conservation and to avoid the species extinction in the wild.

The surveys were conducted in natural populations of Haldina cordifolia in the forest areas of three states of central India namely Madhya Pradesh, Chhattisgarh and Maharashtra. Based on the growth parameters of the individual tree, a total of thirty trees from nine forest divisions of these three states were selected as candidate plus trees (CPTs). Variation was observed in girth at breast height (GBH), total height, and clear bole height (CBH) of trees surveyed. The maximum GBH was recorded in the CPTs of Balrampur (243.75 cm) while the minimum was recorded in Balaghat (115 cm). The maximum height of CPTs was recorded in Dindori (30.25 m) while the minimum was recorded in Allapalli (19 m). The maximum CBH% of total height was recorded in Bilaspur (44.22) while the minimum was recorded in Katghora (37.31). Higher GBH and height of trees may be resulted due to more age of trees. CPTs of Bilaspur were of middle age and showed the highest CBH% (44.22) and relatively low GBH and height when compared with those of Dindori and Balrampur. With age, the trees of Bilaspur will gain more height and girth which will result in higher yield.

This paper is an enumeration of the species of pteridophytes collected from the very little known Dibang Valley district of Arunachal Pradesh, N.E. India, mostly by the first author. 133 species and subspecies, assigned to 50 genera and 22 families, are listed here. Comments on their habitat and distribution are made. The present checklist is intended to be a base-line towards the preparation of a detailed pteridophyte flora of Dibang Valley district.