Production of plantlets from tissue cultures of Lotononis, a southern African veld legume.

A simple procedure is described for the production of large numbers of rooted plantlets from callus cultures of Lotononis bainesii Baker. Highest frequency of shoots was obtained from somatic embryos formed in initiation cultures on Murashige & Shoog medium plus 1 mg/l benzylaminopurine plus 1 mg/l naphtaleneacetic acid. The somatic embryos from these initiation cultures were transferred to media containing 0, 5, 10 or 20 mg/l isopentenyladenine or 0, 1 of 5, 0 mg/l kinetin (1, 8 to 3, 1 shoots per culture) where they re-callused and produced shoots. All shoots obtained from the cultures on media containing 0, 5, 10 or 20 mg/l isopentenyladenine or 0, 1 mg/l kinetin were rooted; 35% of shoots from the cultures on medium containing 5, 0 mg/l kinetin were rooted. Rooting of unrooted shoots from other treatments was readily induced on medium containing 0, 1 mg/l indoleacetic acid.Keywords: callus cultures; forage legume improvement; legumes; lotononis bainesii; plantlets; procedure; rooting; somatic embryos; tissue cultur

Plaster glue complex permittivity response in the microwave range

This paper describes a complementary method for determining dielectric properties of granular materials using the Transmission/Reflection Method in order to estimate their moisture content. The Newton's Complex Interactive Method is used here as a numerical tool to calculate the complex permittivity of the plaster glue material. Results for samples with moisture contents of 35%, 40% and 45% in the range of 100 MHz to 3 GHz are presented

Competition in U.S. farm product markets: do long-run incentives trump short-run market power?

This paper addresses buyer market power in farm product procurement markets. We argue that buyer power concerns are often overstated because traditional models of buyer market power are incapable of depicting the economic interactions that are fundamental to modern agricultural markets, where exchange is governed by stable contractual relationships among buyers and farmers. The exercise of short-run oligopsony power is inimical to the long-run interests of buyers in these settings because below-competitive returns will lead to the exodus of resources from producing the product. Policy proposals grounded in the presumed linkage between concentration, competition, and market power may well be misguided and detrimental to the objectives proponents seek to advance