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Hypocotyl explants of 1 and 10 mm lengths were excised from 12-day-old in vitro-grown seedlings of Albizia richardiana. The larger pieces, after 40 days of culture, developed shoots along with green calli on B5 + BAP (10(-7)-10(-5)M), while the smaller segments produced only green calli on B5+BAP (10(-7)-10(-4)M) medium. Some of the green calli turned morphogenic and started producing somatic embryos with the 2nd sub-culture and shoots from 7th sub-culture onwards. Calli retained the morphogenic potential even after repeated sub-culturing for over two years. The number of embryos in an embryogenic culture varied from 2 to 20 per callus mass of 5-6.5 cm(3). Sucrose at the 2% level in MS medium was optimal for embryogenesis while 4% was optimal for shoot bud differentiation. Higher levels of sucrose (6-10%) caused browning of green calli and also inhibited differentiation into embryos and shoot buds. By selective sub-culturing of 0.1 cm(3) pieces of embryogenic calli on MS+10(-5)M BAP, 46% of the cultures produced somatic embryos. The latter germinated into plantlets on Knop's medium.

Effect of rainwater harvesting (RWH) structures like Contour trench (CT), gradonie (GD), box trench (BT), V-ditch (VD) and afforestation withEmblica officinalis Gaertn (planted in August, 2005) were studied in <10%, 10-20% and >20% slopes with a view to improve soil status, plant growth, sequester carbon and rehabilitate hills for local benefits. Soil pH and EC decreased and percent soil, SOC, NO 3 -N and PO 4 -P increased in June 2010 over 2005. Enhanced soil water and nutrients in <10% slope facilitated height and collar diameter growth of E. officinalis. Soil water was 14.0 and 51.4% greater in >20% and <10% slopes, respectively than in 10-20% slope, whereas it was 17.8, 16.1, 24.2 and 14.0% greater in CT, GD, BT and VD treatments, respectively over control. The highest plant growth was in CT plots in all slopes. Second best treatment was BT in <10% slope and VD in other slopes. Conclusively, RWH and afforestation facilitated soil improvement but CT/BT treatments were more efficient in conserving soil and water facilitating plant growth and helped restore the degraded hill. However, further research is required on soil water use and its partitioning in different vegetation component and the benefits accrued from it for the local people.

 Azadirachta indica seed samples were collected from four different agro-ecological regions (AERs) viz., AER-2, AER-4, AER-5A and AER-5B of Gujarat state, India during 2000 to 2002 with an aim to assess variability in azadirachtin, oil and fatty acids content of the seeds and assess correlation of these parameters with morphological characters.Azadirachtin, oil and fatty acids content indicated significant (p<0.01) variations between years and AERs in Gujarat. The azadirachtin ranged from 142 to 9 527 μg⋅g -1 seed kernel with an average of 2 426 μg⋅g -1 for the state. AER-5B recorded highest azadirachtin and oil content. Fatty acid composition was found to be affected by environmental factors particularly varying degree of annual rainfall and temperature during fruit ripening period. Conclusively trees growing in AER-5B performed better in term of azadirachtin, oil and stearic acid content. Tree girth at breast height showed no significant relation with these biochemicals.

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