NOPR Collection:

Efficient regeneration of sorghum, Sorghum bicolor (L.) Moench, from shoot-tip explant

Mon, 01 Dec 2003 00:00:00 GMT

Title: Efficient regeneration of sorghum, Sorghum bicolor (L.) Moench, from shoot-tip explant Authors: Syamala, D; Devi, Prathibha Abstract: Novel protocols for production of multiple shoot-tip clumps and somatic embryos of Sorghum bicolor (L.) Moench were developed with long-term goal of crop improvement through genetic transformation. Multiple shoot-tip clumps were developed in vitro from shoot-tip explant of one-week old seedling, cultured on MS medium containing only BA (0.5, 1 or 2 mg/l) or both BA (1 or 2 mg/I) and 2,4-D (0.5 mg/l) with bi-weekly subculture. Somatic embryos were directly produced on the enlarged dome shaped growing structures that developed from the shoot-tips of one-week old seedling explants (without any callus formation) when cultured on MS medium supplemented with both 2,4-D (0.5 mg/l) and BA (0.5 mg/I). However, the supplementation of MS medium with only 2, 4-D (0.5 mg/l) induced compact callus without any plantlet regeneration. Each multiple shoot-clump was capable of regenerating more than 80 shoots via an intensive differentiation of both axillary and adventitious shoot buds, the somatic embryos were capable of 90% germination, plant conversion and regeneration. The regenerated shoots could be efficiently rooted on MS medium containing indole-3-butyric acid (IBA 1 mg/l). The plants were successfully transplanted to glasshouse and grown to maturity with a survival rate of 98%. Morphogenetic response of the explants was found to be genotypically independent. Page(s): 1482-1486

In vitro propagation of emetic nut Randia dumetorum (Lamb.)

Mon, 01 Dec 2003 00:00:00 GMT

Title: In vitro propagation of emetic nut Randia dumetorum (Lamb.) Authors: Begum, Ferdousi; Didarul Islam, Kazi Mohammed; Paul, Rathindra Nath; Mehedi, Masfique; Rani, Shyamole Abstract: An efficient protocol for in vitro shoot multiplication of Randia dumetorum (Emetic nut) has been developed. The seeds of R. dumetorum were germinated in vitro in MS medium in 5 weeks. Subsequent propagation using shoot tip as an explant was carried out in MS medium along with different concentrations and combinations of BAP (0.5-2.0) and NAA (0.0-2.0). Maximum shoot multiplication was obtained (12.7 shoots per shoot tip) in MS medium containing 1mg/L BAP and 1mg/L NAA. Micropropagated shoots were rooted in 1/2MS medium supplemented with 1 mg/l IBA. This is the first report of in vitro plant propagation of R. dumetorum. In vitro grown plantlets showed a survival rate of 70% after 2 months of tranplantation to natural environment. Page(s): 1479-1481

Optimization of wedelolactone accumulation in shoot cultures of Eclipta alba

Mon, 01 Dec 2003 00:00:00 GMT

Title: Optimization of wedelolactone accumulation in shoot cultures of Eclipta alba Authors: Jayathirtha, M G; Mishra, S H Abstract: Influence of different environmental factors on accumulation of wedelolactone, a potential anti-hepatotoxic principle of E. alba in shoot cultures was investigated. A significant increase in the content of wedelolactone due to kinetin treatment, temperature change and photoperiod alteration in shoot cultures was observed, incorporation of phenylalanine in the medium also increased content of wedelolactone significantly in a dose-dependent manner. Page(s): 1476-1478

Efficacy of Euphorbia splendens and Leonotis nepetaefolia on aflatoxin producing fungi Aspergillus flavus and Aspergillus parasiticus

Mon, 01 Dec 2003 00:00:00 GMT

Title: Efficacy of Euphorbia splendens and Leonotis nepetaefolia on aflatoxin producing fungi Aspergillus flavus and Aspergillus parasiticus Authors: Abubacker, M N; Ramanathan, R Abstract: Efficacy of three different concentrations (5, 10 and 15 mg/ml) of dry flower powder of E. splendens and L. nepetaefolia was tested on the growth of aflatoxin-producing toxigenic strains of fungi A. flavus (NCBT 101) and A. parasiticus (NCBT 128) in Sabouraud dextrose agar medium (SDA). Maximum (75%) inhibition of growth of A. flavus was seen at 15 mg/ml concentration of E. splendens flower dry powder, while A. parasiticus showed 50% inhibition of growth at 10 and 15 mg/ml concentrations. Total inhibition (100%) of growth of A. flavus was seen at 10 and 15 mg/ml for L. nepetaefolia and maximum (75%) inhibition of growth was seen for A. parasiticus at 15 mg/ml concentration. Bioassay with groundnut seeds soaked with different concentrations of flower extract proved that both fungi were incapable of infecting the seeds at 10 and 15mg/ml of L. nepetaefolia flower extracts. Page(s): 1473-1475