Elemental components and maps of fine sand in Taklimakan Desert

ABSTRACT PIXE analysis of a fine sand sample from the Taklimakan Desert revealed 20 elements, of which Na, Mg, Al, Si, Cl, K, Ca, Ti and Fe were found to be the major components. Comparing the determined values of the fine sand sample with determined values of China Loess (CJ-1) and Simulated Asian Mineral Dust (CJ-2), the concentration level (except for Cl) were similar, and Cl was 10 and/or 5 fold. Therefore, fine sand from the Taklimakan Desert was assumed to be the origin of the loess and Aeolian dust transported to Japan. Maps of Al, Si, K and Fe were very similar, but the Ca map was close to the STIM image of the high-energy window, indicating that Ca was likely in relatively large particles

In vitro direct rhizogenesis from Gerbera jamesonii Bolus leaf

The present report describes an original protocol for in vitro direct induction of roots from leaf explants of gerbera for the first time. Since gerbera has immense potential as a premium cut-flower, the major attempts were made on in vitro mass propagation chiefly through in vitro multiple shoot proliferation or callus regeneration. Nevertheless, rhizogenesis could be impending an unattempted method with its yet-to-be known advantages. In our study, the optimum conditions for direct root induction from leaf explants were assessed employing tissue culture technique. Leaves were inoculated to MS medium containing no or variable auxin sources and concentrations namely, 2,4-dichlorophenoxyacetic acid, indole-3-acetic acid (IAA), indole-3-butyric acid or α-naphthaleneacetic acid for root induction. It was evident that the maximum root induction (with a frequency of 92.6 %) occurred on MS media fortified with 1.5 mg l−1 IAA, wherein root induction was observed as early as 11 days of culture and an average of ~19 roots with ~13 mm length was obtained from 4 cm2 leaf segment after 45 days of culture. Stereo microscopic observation revealed the induction of roots and gradual developmental stages of rhizogenesis. The efficiency of direct root induction without any interim growth stages (such as, callus or shoots) in our study offers a reproducible system that could provide a model protocol for more comprehensive developmental studies on root growth