Rice is the principal crop of northeastern region of India, where a considerable range of diversity exists. The germplasm collection has also unfold the occurrence of large number of rice landraces in the region. Between 1985 and 2002, a total 2639 accessions of rice germplasms including their wild relatives have been collected. Most of these germplasm material have been conserved in the National Gene Bank, New Delhi following their necessary characterization and evaluation. With the establishment of the Regional Gene Bank Module with medium-term storage facilities (6-7 C with 40-45% relative humidity) at Barapani, Meghalaya, the rice germplasm conservation (ex situ) have been initiated in the region.

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The present study describes the structure, composition and regeneration of tree species in undisturbed and disturbed tropical forests in Bhuban hills in southern Assam, India. The study area is part of one of the globally recognized biodiversity hot spots and in spite of the increasing human activities in these forests, so far no information is available on their impacts on plant assemblages in the area. In each forest, the vegetation was analysed through 50 quadrats (10 m × 10 m) in a belt transect of 500 m × 10 m. A total of 49, 47 and 42 tree species were recorded in disturbed forests and 62, 61 and 60 species in undisturbed forests. The average tree density and basal area were significantly higher in undisturbed forests (708.67 and 42.01 m 2 ha −1 , respectively) than disturbed forests (443.33 and 18.44 m 2 ha −1 , respectively). The population structure of tree species in disturbed forests showed a fluctuating curve, and in undisturbed forests, it was a reversed J-shaped curve. The present study reveals that the species richness, diversity, density and basal area have significantly declined (P < 0.01) due to anthropogenic disturbances. As reflected from the population structure, most of the tree species in disturbed forests showed poor regeneration status. If degradation of these forests continues at the present pace, several of these species which are providing various ecosystem services to the local human communities may disappear in the very near future.

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Cucumbers (Cucumis sativus) are considered to be native to India. The germplasm of cultivated and wild relatives is shown to grow in very diverse agroecological conditions of the country. The north-eastern region is shown to hold special significance for wild and cultivated germplasm. The disease and specific adaptation characters are pointed out. Future scope for commercial growing and research needs are emphasised.