An in vitro method for propagation of Holarrhena antidysenterica Wall. has been developed using nodal explants from mature trees growing in the field. Irrespective of concentrations and combinations of growth regulators used, the axillary and terminal buds sprouted and elongated when inoculated on Murashige and Skoog (MS) medium. The highest numbers of shoots were formed when sprouted shoots were subcultured from MS basal medium onto MS medium containing 2 mg dm -3 N 6 -benzyladenine (BA) and 0.5 mg dm -3 α-naphthalene acetic acid (NAA). The shoot number further increased upon subculture on MS medium containing 0.5 mg dm -3 BA. By repeated sub-culturing of shoots derived from nodal axillary buds, a high frequency multiplication rate was established. The elongated shoots were excised and rooted in auxin free MS basal medium. Ex vitro rooting of in vitro formed shoots was achieved upon dipping the microshoots for 2 min in 2 mg dm -3 of indole-3-butyric acid solution. Successful field establishment and high (80 -90 %) survival of plants was observed.Additional key words: benzyladenine, ex vitro rooting, indole-3-butyric acid, micropropagation, naphthalene acetic acid. ⎯⎯⎯⎯Holarrhena antidysenterica Wall. (H. pubescence) is a typical Indian medicinal plant widely used as a cure for dysentery and diarrhea. This medicinal plant is propagated by seeds but its seed viability and germinability are very poor. Clonal propagation through conventional methods of propagation like rooting of cuttings and grafting has not been successful (Ahmed et al. 2001). Although some attempts were on tissue cultures of H. antidysenterica (Panda et al. 1991, 1992a,b, Ahmed et al. 2001, Raha and Roy 2001, 2003, Agrawal et al. 2005, rapid in vitro propagation has not been achieved. In this paper, based on a detailed study, we report rapid in vitro production of H. antidysenterica using nodal buds of mature tree. We report the production of more number of shoots with high frequency of regeneration than the earlier reports (Ahmed et al. 2001, Raha and Roy 2001, Agrawal et al. 2005.Nodal buds were collected from 15 -20 year old trees from Tirumala forest of Andhra Pradesh, India, and were initially washed with running tap water for 15 min to remove the latex, and then with 5 % Labolene for 15 min followed by washing in running tap water and then 4 -5 times with distilled water. Surface sterilization was done by treating explants with 0.1 % mercuric chloride for 2 min and with 70 % alcohol for 15 s and each surface sterilization was followed by 5 -6 rinses in sterile distilled water. The explants were then inoculated on agar gelled medium in 25 × 150 mm culture tubes or 150 cm 3 conical flasks. Initial experiments were tried by incorporating N 6 -benzyladenine (BA; 0.5 -5 mg dm -3 ) alone and in combination with α-naphthalene acetic acid (NAA) and indole-3-acetic acid (IAA) (0.1 -0.5 mg dm -3 ) in Murashige and Skoog (MS) medium. After assessing the effect of BA on shoot multiplication on MS medium, its effects on the other basal media like Woody ...

SUMMARYGypsum application and irrigation increased yield in early maturing groundnut genotypes in experiments using line source and conventional irrigation. Response to gypsum varied with genotype; with some gypsum increased yields at all water application rates, in some genotypes there was no response, while with others gypsum increased yield in drought conditions.In a separate study of the effect of gypsum and drought on pod initiation and development in three groundnut genotypes, gypsum did not greatly influence pod initiation when adequate irrigation was applied, but was beneficial when water was withheld during pod set and again during pod filling. Crops where the combination of gypsum and genotype were most advantageous in the first drought period subsequently grew more slowly so that there were no final differences in response to gypsum. Cultivar EC 76446(292) had a higher requirement for gypsum and was more susceptible to drought than the other two genotypes.

ABSTRACITwo naturally occurring species of the genus Alternanthera, namely A. ficoides and A. tenella, were identified as C3-C4 intermediates based on leaf anatomy, photosynthetic CO2 compensation point (r), 02 response of r, light intensity response of r, and the activities of key enzymes of photosynthesis. A.

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SUMMARYThe hydraulic press was compared with the dew point psychrometer and the pressure chamber methods for measuring leaf water potential (Ψ) in groundnuts (Arachis hypogaea L.). For measurements on the same leaf, regression analysis revealed that the slopes did not differ significantly from unity. An analysis of functional relations between measurements made by the press and the dew point psychrometer or the press and the pressure chamber showed that the error variance of the press was similar to those of the two other methods. Therefore, we conclude that for groundnuts the performance of the press, the dew point psychrometer and the pressure chamber are similar.