Le coton biologique au Paraguay. 1. Construction de la filière et contraintes économiques

Organic cotton production in Paraguay. 1. Some economic limitations for a novel industry. Paraguay, whose small farmers are traditionally cotton growers, has begun to crop and process organic cotton since 2003. An exploratory study was carried out in order to have a better knowledge of the way the organic cotton production has developed and to detect eventual economic limitations. The study was achieved in 2008 during the cotton harvest period by interviewing the actors from the farm to the industrial level. The organic cotton industry was built by a single company in a favorable national (20 years of organic production for a diversity of crops) and international (an increasing demand for organic products, including cotton) context. This single company applied a strategy of creating alliances with NGOs, public authorities and other private operators, in order to increase farm production – by adding new farmers – and textile manufacture and trade worldwide. We detected three kinds of economic limitations. Firstly, organic cotton production still remained largely dependent on the conventional cotton industry for the supply of seed. Secondly, the cumbersome certification process at farm level and its cost associated with increased logistic problems derived from the increase in geographical dispersion of small producers appeared to seriously limit the possibilities for expansion. Thirdly, although the price paid for organic cotton was 12-14% higher in 2008, the obligation for the farmers to sell drier cotton and a longer buying process resulting in delayed cash payments led many farmers to sale a large part of their organic cotton to conventional buyers. We recommend in-depth studies on these three topics to acquire a better knowledge of their extent in terms of intensities and variations, and to propose measures to mitigate them

COUPLER SAVOIRS ACADEMIQUES ET METHODES INFORMATIQUES POUR MIEUX ORIENTER LES OBSERVATIONS DE TERRAIN

International audienceBiological control through conservation agriculture or enhanced control via natural enemies are cost-effective strategies suitable for implementation in farming conditions of sub-Saharan African countries. One issue concerns the identification of host plants of crop pests and their parasitoïds in natural habitats. The situation regarding cereal stem borers identified in lowland regions in Benin was investigated. The lepidopteran pests identified were Sesamia calamistis, Busseola fusca, Mussidia nigrivenella, Coniesta ignefusalis and Thaumatotibia leucrotreta. A database was compiled from published findings to better target field studies on their secondary host plants and parasitoids. The information collected, compared with plant survey data, indicated that the Poaceae species Sporobolus pyramidalis and Rottboellia cochinchinensis, and species belonging to the Hyparrhenia and Pennisetum genera should be monitored in priority.RÉSUMÉ La lutte biologique par conservation ou par renforcement de la régulation par les ennemis naturels apparait comme une stratégie économiquement adaptée au contexte de l'agriculture des pays d'Afrique sub-saharienne. Une question posée est celle de l'identification des plantes-hôtes des ravageurs des cultures et de leurs parasitoïdes dans les habitats naturels. Le cas des lépidoptères foreurs des céréales a été abordée dans un bas-fonds au Bénin. Les lépidoptères ravageurs identifiés ont été Sesamia calamistis, Busseola fusca, Mussidia nigrivenella, Coniesta ignefusalis et Thaumatotibia leucrotreta. Afin de mieux orienter les observations de terrain sur leurs plantes-hôtes secondaires et leurs parasitoïdes, une base de données a été constituée à partir des travaux publiés. Les informations ainsi recueillies, croisées avec les relevés floristiques, indiquent les espèces à observer prioritairement, les Poacées des genres Hyparrhenia et Pennisetum et les espèces Sporobolus pyramidalis et Rottboellia cochinchinensis

Flutuação populacional das pragas do algodoeiro no sistema de plantio convencional versus sistema de plantio adensado.

No sistema de plantio adensado do algodoeiro as entrelinhas se fecham mais rápido o que pode levar a modificações no microclima e na relação artrópode-planta. Este trabalho teve por objetivo avaliar se a dinâmica populacional dos insetos-praga do algodoeiro no sistema de plantio convencional e adensado. O ensaio foi instalado Campo Experimental do Instituto Mato-grossense do Algodão (IMA) em Primavera do Leste (MT), na safra 2008/09. A cultivar utilizada foi a COODETEC 408, plantada em 21 de fevereiro de 2009. O delineamento experimental foi o inteiramente casualizado com dois tratamentos (plantio convencional e plantio adensado) e 10 repetições. Cada repetição tinha 70 x 70m (0,49 ha); o espaçamento entre linhas foi de 0,9m para o plantio convencional e 0,45m para o plantio adensado. As amostragens das pragas foram semanais e em 10 plantas/repetição, utilizando-se o caminhamento em zigue-zague. Os dados foram submetidos à Análise de Variância (ANAVA) e nas condições estudadas não se verificou diferença significativa na dinâmica populacional do pulgão Aphis gossypii, Alabama argillacea, Spodoptera eridania, Pseudoplusia includens e Heliothis virescens entre os sistemas de plantio adensado e convencional. (Résumé d'auteur

Widespread distribution and a new recombinant species of Brazilian virus associated with cotton blue disease

<p>Abstract</p> <p>Background</p> <p>Cotton blue disease (CBD), an important global cotton crop pathology responsible for major economic losses, is prevalent in the major cotton-producing states of Brazil. Typical CBD symptoms include stunting due to internodal shortening, leaf rolling, intense green foliage, and yellowing veins. Atypical CBD symptoms, including reddish and withered leaves, were also observed in Brazilian cotton fields in 2007. Recently, a <it>Polerovirus </it>named Cotton leafroll dwarf virus (CLRDV) was shown to be associated with CBD.</p> <p>Results</p> <p>To understand the distribution and genetic diversity of CLRDV in Brazil, we analyzed 23 CBD-symptomatic plants from susceptible cotton varieties originating from five of the six most important cotton-growing states, from 2004–2007. Here, we report on CLRDV diversity in plants with typical or atypical CBD symptoms by comparing viral coat protein, RNA polymerase (RdRp), and intergenic region genomic sequences.</p> <p>Conclusion</p> <p>The virus had a widespread distribution with a low genetic diversity; however, three divergent isolates were associated with atypical CBD symptoms. These divergent isolates had a CLRDV-related coat protein but a distinct RdRp sequence, and probably arose from recombination events. Based on the taxonomic rules for the family <it>Luteoviridae</it>, we propose that these three isolates represent isolates of a new species in the genus <it>Polerovirus</it>.</p

Hétéroptères phytophages et prédateurs d'Afrique de l'Ouest / Phytophagous and predatory Heteroptera in West Africa

Those concerned with biodiversity and integrated pest management consider it vital for farmers and agricultural professionals to be able to identify insect pests and their natural enemies. This clear and well-illustrated bilingual guide provides a brief description of the main species of phytophage and predatory bugs found in West Africa, principally in cotton, corn, cowpea, soybean and sorghum. Tous ceux qui se soucient de la biodiversité et de la lutte antiparasitaire intégrée estiment que les agriculteurs et professionnels de l'agriculture doivent être capables d'identifier les parasites et leurs ennemis naturels. Ce guide bilingue clair et bien illustré dresse une brève description des principales espèces d'hétéroptères phytophages et prédateurs que l'on trouve en Afrique de l'Ouest, principalement dans le coton, le maïs, le dolique à œil noir (Vigna unguiculata), le soja et le sorgho.Those concerned with biodiversity and integrated pest management consider it vital for farmers and agricultural professionals to be able to identify insect pests and their natural enemies. This clear and well-illustrated bilingual guide provides a brief description of the main species of phytophage and predatory bugs found in West Africa, principally in cotton, corn, cowpea, soybean and sorghum. Tous ceux qui se soucient de la biodiversité et de la lutte antiparasitaire intégrée estiment que les agriculteurs et professionnels de l'agriculture doivent être capables d'identifier les parasites et leurs ennemis naturels. Ce guide bilingue clair et bien illustré dresse une brève description des principales espèces d'hétéroptères phytophages et prédateurs que l'on trouve en Afrique de l'Ouest, principalement dans le coton, le maïs, le dolique à œil noir (Vigna unguiculata), le soja et le sorgho.Those concerned with biodiversity and integrated pest management consider it vital for farmers and agricultural professionals to be able to identify insect pests and their natural enemies. This clear and well-illustrated bilingual guide provides a brief description of the main species of phytophage and predatory bugs found in West Africa, principally in cotton, corn, cowpea, soybean and sorghum. Tous ceux qui se soucient de la biodiversité et de la lutte antiparasitaire intégrée estiment que les agriculteurs et professionnels de l'agriculture doivent être capables d'identifier les parasites et leurs ennemis naturels. Ce guide bilingue clair et bien illustré dresse une brève description des principales espèces d'hétéroptères phytophages et prédateurs que l'on trouve en Afrique de l'Ouest, principalement dans le coton, le maïs, le dolique à œil noir (Vigna unguiculata), le soja et le sorgho.Those concerned with biodiversity and integrated pest management consider it vital for farmers and agricultural professionals to be able to identify insect pests and their natural enemies. This clear and well-illustrated bilingual guide provides a brief description of the main species of phytophage and predatory bugs found in West Africa, principally in cotton, corn, cowpea, soybean and sorghum. Tous ceux qui se soucient de la biodiversité et de la lutte antiparasitaire intégrée estiment que les agriculteurs et professionnels de l'agriculture doivent être capables d'identifier les parasites et leurs ennemis naturels. Ce guide bilingue clair et bien illustré dresse une brève description des principales espèces d'hétéroptères phytophages et prédateurs que l'on trouve en Afrique de l'Ouest, principalement dans le coton, le maïs, le dolique à œil noir (Vigna unguiculata), le soja et le sorgho

Sequestration of cholesterol within the host late endocytic pathway restricts liver-stage Plasmodium development

While lysosomes are degradative compartments and one of the defenses against invading pathogens, they are also hubs of metabolic activity. Late endocytic compartments accumulate around Plasmodium berghei liver-stage parasites during development, and whether this is a host defense strategy or active recruitment by the parasites is unknown. In support of the latter hypothesis, we observed that the recruitment of host late endosomes (LEs) and lysosomes is reduced in uis4(−) parasites, which lack a parasitophorous vacuole membrane protein and arrest during liver-stage development. Analysis of parasite development in host cells deficient for late endosomal or lysosomal proteins revealed that the Niemann–Pick type C (NPC) proteins, which are involved in cholesterol export from LEs, and the lysosome-associated membrane proteins (LAMP) 1 and 2 are important for robust liver-stage P. berghei growth. Using the compound U18666A, which leads to cholesterol sequestration in LEs similar to that seen in NPC- and LAMP-deficient cells, we show that the restriction of parasite growth depends on cholesterol sequestration and that targeting this process can reduce parasite burden in vivo. Taken together, these data reveal that proper LE and lysosome function positively contributes to liver-stage Plasmodium development

Studi Eksperimen:Efektivitas Pelatihan Komik Terhadap Kreativitas dan Pengungkapan diri

ABSTRAK Remaja merupakan masa untuk mencoba berada dalam peran sosial yang baru dalam pertumbuhan selanjutnya. Dalarn perubahan sosialisasi, para remaja dituntut untuk dapat menemukan identitas diri Selain itu, pertumbuhan badannya yang pesat meningkatkan kebutuhan faal dan memiliki dorongan beraktivitas sangat besar. Ketidakharmonisan gerak, kecemasan, kelchawatiran, self concept yang rendah dapat mengarahpada tindakan destruktif untuk menunjukkan kekuatannya. Tujuan penelitian untuk mengetahui efektivitas pelatihan komik terhadap kreativitas dan pengungkapan dm di kalangan remaja. Variabel bebas nya ialah pelatihan keterampilan membuat komik, sedang variabel tergantungnya adalah tingkat kreativitas dan pengungkapan diri. Alat ukur eksperimen digunakan tes kreativiotas Torrance berupaa-kreativitas Figural tipe B sebagai bagian dari Torrance Test of Creative Thinking. Analisis data digunakan metode Anova. Hasil analisis menunjukkan bahwa ada peningkatan hasil dalam segala kemampuan pada kelompok eksperimen, tidak adanya perbedaan signifikan antara kemampuan kreativitas kelompok eksperimen dengan kelompolc kontrol, ada perbedaan signifikan antara kemampuan mengungkapkan diri kelompok eksperimen dengan kelompok kontrol