Fertilizer market reform and the determinants of fertilizer use in Benin and Malawi

Most countries in sub-Saharan Africa have reduced or eliminated fertilizer subsidies and liberalized input marketing as part of the reform process that began in the early 1980s. The effect on fertilizer prices and use is one of the most frequently mentioned criticisms of liberalization. The effect of these reforms, however, has varied widely across countries. The study finds that fertilizer use is closely related to crop mix and access to inputs on credit, but not to household income.. In Benin, 88 percent of the fertilizer purchased by farmers is bought on credit through the integrated cotton marketing system managed by the parastatal SONAPRA. However, almost one third of this fertilizer is diverted to maize and other crops. In Malawi, tobacco is the most important cash crop among smallholders, but less than half the tobacco growers are able to purchase fertilizers on credit. Maize accounts for about 60 percent of the fertilizer use, compared to less than a third for tobacco. This difference in the tradability of the main crop being fertilized helps explain some of the difference in performance. The results demonstrate some of the paths by which cash crop and food crop production may be complementary. This can occur through the residual effect of fertilizer on food crop production, through the alleviation of cash constraints for the purchase of fertilizer, and through the availability of inputs on credit.Thus, the benefits of export liberalization must be weighed against the risk that it will weaken the enforceability of seasonal agricultural credit, with indirect consequences for food crop productivity.Cash crops Developing countries Case studies. ,Fertilizer industry. ,Subsidies. ,

Interview: Nicholas McGeehan of Human Rights Watch on links between the UK and undemocratic regimes in the Gulf

Democratic Audit features short audio interviews with leading experts on the state of democracy and human rights. For our first interview, Richard Berry spoke to Nicholas McGeehan, Middle East researcher at Human Rights Watch, on the way rulers of Gulf states have been cracking down on dissent at home while simultaneously deepening their relationships within the UK. Listen to the interview here

Marketing constraints on rice exports from Viet Nam

The paper describes the spectacular growth of rice exports from Viet Nam during the period 1989 to 1997. From a situation of food shortages, the country is now the second largest rice exporter after Thailand. Export projections indicate that there is potential for further export growth in all but the most pessimistic scenarios. This potential is constrained, however, by the relatively underdeveloped marketing system. A few large state enterprises have access to capital and export licenses, but private traders and millers are generally small and medium enterprises with limited credit and no legal access to world markets. Recent policy changes to promote internal trade liberalization and competition between central and provincial state enterprises are encouraging, but need to be extended to allow private traders to export.Rice Viet Nam ,Export marketing ,trade liberalization ,

Molecular biology of amitraz resistance in cattle ticks of the genus Rhipicephalus

Amitraz is an important product for the control of cattle ticks around the world. In comparison with other products for the control of ticks, it is quite affordable and it has a rapid knock-down effect. It binds with and activates adrenergic neuro-receptors of animals and it inhibits the action of monoamine oxidases (MAO). Resistance to amitraz has been documented in Rhipicephalus microplus, R. decoloratus and R. appendiculatus. Four mechanisms of resistance have been proposed, each of which is supported by evidence but none of which has been definitively confirmed as the cause of resistance in the field. The proposed mechanisms include genetic target site insensitivity in two G protein-coupled receptors, the beta-adrenergic octopamine receptor (BAOR) and the octopamine/tyramine receptor (OCT/Tyr), increased expression or activity of monoamine oxidases and increased expression or activity of the ATP binding cassette transporter

Regulation of Estrogen Receptor alpha Ubiquitination and Proteasome-mediated Receptor Degradation

Thesis (PhD) - Indiana University, Cellular and Integrative Physiology, 2008Breast cancer is the most common cancer among women, and the majority (~70%) express estrogen receptor-alpha (ERα), thereby exhibiting estrogen-dependent growth. Antiestrogen therapies block ERα-mediated cell growth, either by blocking ERα function or by triggering ERα degradation. ERα is recognized for degradation by the 26S proteasome through the addition of ubiquitin protein tags onto ERα lysine residues. However, the specific receptor lysines that are ubiquitinated have not been identified. Two receptor lysines, K302 and K303, located in the hinge-region of ERα, serve multiple regulatory functions, and we examined whether these residues might also regulate receptor ubiquitination or are targets themselves for ubiquitination. An ERα protein was generated that contained lysine-to-alanine substitutions at these two residues. Comparisons were made between the unmodified ERα (wtERα) and the mutant receptor ERα-K302A, K303A (ERα-AA). The effect of the proteasome inhibitor MG132, Hsp90 inhibitor geldanamycin (GA), and ER ligands 17β-estradiol (E2), tamoxifen (OHT), and the pure antiestrogen ICI 182,780 (ICI), were examined for their effect on receptor ubiquitination, degradation, and receptor activity. In the absence of ligand, ERα-AA displayed rapid ubiquitination and degradation due to elevated association with the ubiquitinylation enzyme CHIP and the proteasome-associated cochaperone Bag1. E2 or ICI induced rapid degradation of wtERα; however, ERα-AA was less efficiently degraded by these ligands. Furthermore, ERα-AA was also resistant to ICI-induced ubiquitination, suggesting that these lysines are ubiquitinated in response to the antiestrogen. ERα-AA activity was decreased in the unliganded state and elevated in response to E2, concordant with receptor stability in these two states. These data provide the first evidence that K302/303 protect ERα from basal degradation and are necessary for efficient E2 and ICI-induced turnover in breast cancer cells, revealing a previously unexplored mechanism for regulating ERα stability and activity