Long-term maintenance of Cylindrocladium strains and procedures for inoculum production

Les techniques présentées permettent une conservation à long terme des souches de Cylindrocladium pour les préserver d'importants changements morphologiques et physiologiques. Le principe des méthodes appliquées, leurs principaux avantages, le matériel végétal nécessaire, le temps requis et les résultats attendus sont présentés. Matériel et méthodes. Le matériel de laboratoire nécessaire, ainsi que le détail des neuf étapes utilisées pour la purification monospore de souches de Cylindrocladium, leur conservation à long terme, et la production de conidies et de microsclerotes sont décrits. Résultats. Une fois réactivées, les souches purifiées produisent des colonies qui s'accroissent activement en 48-72 h. De telles colonies peuvent alors être aisément utilisées pour la production de conidies ou de microsclerotes. (Résumé d'auteur

Utilisation du maïs doux comme plante piège pour contrôler la noctuelle de la tomate Helicoverpa zea

L'utilisation d'une plante piège qui attire le ravageur et le détourne de la culture principale est une méthode de protection des cultures agro-écologique et respectueuse de l'environnement. Nous avons étudié l'utilisation du maïs doux comme plante piège pour protéger les cultures de tomate de la noctuelle Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae). Nos résultats montrent que les soies de maïs doux sont des sites de ponte privilégiés pour H. zea et que la synchronisation de l'apparition des soies et de la floraison de la tomate a pour effet des pontes plus faibles dans les parcelles de tomate avec une bordure de maïs doux que dans celles sans bordure. Cette méthode nécessite aussi la prise en compte de l'effet variétal. Sur 10 variétés de maïs doux testées pour leur attractivité comme site de ponte, la densité d'oeufs déposés varie entre les variétés. Des caractères physiques tels que le poids des soies, leur brunissement et la hauteur du plant peuvent expliquer cette variabilité

An ecologically intensive approach for the design of sustainable horticultural systems in the tropics

Fruit and vegetable growers in the tropics are faced with crop protection issues resulting in food insecurity and low-income in low-input traditional agro-systems. In intensive systems, pesticide-induced adverse impacts on human health and the environment may occur. Setting up an "ecologically intensive" horticulture by modifying agro-systems to mobilize natural regulation mechanisms taking ecological processes as a source of inspiration, has become a major challenge. This implies a shift from a "tactical" approach based on preventive and curative chemical treatments (agro-chemistry) to a "strategic" approach based on preventive and natural methods (agro-ecology) for the regulation of pests/pathogens infestations/infections. Horticultural cropping systems provide ideal frameworks for studying the effects of the planned introduction and management of plant species diversity (PSD), on pest and disease impact. The Cirad Omega3 Project builds on case studies representing a broad range of PSD levels, scales and deployment modalities, according to an a priori typology of pests and diseases based on their life-history traits. Obtained and anticipated outcomes of these studies concern both i) knowledge on ecological pest and disease regulation processes that can be mobilized in horticultural systems, ii) tools and methods for incepting and evaluating innovating pest and disease-resilient cropping systems. We present here the global approach and first results obtained within this framework regarding i) introduction of service plants with sanitizing/ allelopathic effect managed as green manure for reducing tomato bacterial wilt caused by Ralstonia solanacearum, ii) potential of trap crops/barriers for reducing infestation and damage of tomato fruit worms Helicoverpa armigera on okra in Niger and Helicoverpa zea on tomato in Martinique. Results of these case studies on non-specific disease and pests with respectively low and high dispersal ability, provide decision rules which help set up models to predict the impact of PSD deployment modes on the studied bio-aggressors or other pathogens/pests with similar life-history traits. (Résumé d'auteur

Effect of Fertilizer Faeces on Parameter of Physical Chemistry in Peat Swamp Soil in the Media

The research was conducted from March 2014 in the Laboratory Management ofWater Quality, Faculty of Fisheries and Marine Sciences University of Riau Pekanbaru.The method used in this study is an experimental method using a Random Block Design(RAL) with one factor, 5 treatments and 3 replications. The treatment used in thisexperiment is P0: Without application of fertilizer faeces (control), P1: faeces fertilizer300g/m2, P2: faeces fertilizer 450g/m2, P3: faeces fertilizer 600g/m2, P4: faeces fertilizer750g/m2. Result showed that the faeces fertilizer amounts affect various physical andchemical water quality and well as soil chemistry of peat, and may increase some of thephysical parameter of water quality and soil chemistry of peat swamp and fainally Togood fertility for the growth of organisms in the water

Analisis Faktor-Faktor Yang Mempengaruhi Kinerja Sistem Informasi Akuntansi (Survey pada Bank Perkreditan Rakyat di Wilayah Sukoharjo)

Penelitian ini bertujuan untuk mengetahui dan memperoleh bukti empiris tentang pengaruh keterlibatan pengguna, kemampuan teknik personal, dukungan manajemen puncak dan program pelatihan dan pendidikan terhadap kinerja system informasi akuntansi. Populasi yang digunakan dalam penelitian ini adalah seluruh Bank Perkreditan Rakyat di Sukoharjo yang terdaftar di Perhimpunan Bank Perkreditan Rakyat seluruh Indonesia yang berjumlah 21 bank. Metode pengambilan sampel dengan cara metode convenience. Jumlah sampel yang terkumpul sebanyak 4 bank. Dan kuesioner yang kembali dan dapat diolah sebanyak 50 kuesioner. Data yang telah dikumpulkan dianalisis dengan menggunakan analisis data yang terlebih dahulu dilakukan dengan pengujian asumsi klasik sebelum melakukankan pengujian hipotesis. Pengujian hipotesis dalam penelitian ini menggunakan analisis linier berganda dengan uji t, uji f, multikolinearitas, autokorelasi, dan heteroskedastisitas. Dalam uji validitas dan reliabititas menunjukan bahwa seluruh item pertanyaan dalam kuesioner untuk variabel independen dan dependen adalah valid dan reliabel. Adapun uji asumsi klasik menunjukan bahwa data terdistribusi secara normal, sedangkan hasil uji asumsi klasik yang lain menunjukan bahwa untuk seluruh variabel terbebas dari multikolinearitas dan heteroskedastisitas. Model regresi yang dihasilkan baik dan tidak bias. Hasil penelitian ini menunjukan bahwa variabel keterlibatan pengguna, kemampuan teknik personal, dukungan manajemen puncak dan program pelatihan dan pendidikan berpengaruh terhadap kinerja Sistem Informasi Akuntansi. Hasil analisis keterlibatan pemakai diperoleh nilai thitung sebesar 4,485 > dari ttabel 2,021, analisis pelatihan dan pendidikan diperoleh nilai thitung sebesar 2,591 > dari ttabel 2,021, analisis kemampuan teknik personal diperoleh nilai thitung sebesar 2,606 > dari ttabel 2,021 dan analisis dukungan manajemen puncak diperoleh nilai thitung sebesar 2,312 > dari ttabel 2,021

Impacts of inter-row grass cover on soil biological fertility in tomato crop in Martinique. PoS2-52

The Hemiptera Bemisia tabaci (Gennadius) species is one of the main tomato pest in Martinique, due to its role in the transmission of a variety of plant viruses (Urbino et al., 2003). One of the most effective ways to regulate its infestation in agroecology is to keep grassed inter-rows in tomato crops (Bezerra et al., 2004). This practice may have benefits for soil health such as promotion of biological activity. However, it may in some case reduce yields due to resource competition with the main crop (Singh et al., 2015). Our objective was thus to determine whether having grassed inter-rows would improve soil biological fertility in tomato crop. To do so, we monitored the biological activity in bare and grassed tomato inter-rows (spontaneous vegetation, dominated by graminoids) between plantation and flowering stage (March to May 2017) in an experimental site in Le Lamentin (Martinique, France). We used two indicators of biological fertility: lamina-bait decomposition of a labile (bean) and recalcitrant (acacia) substrate to assess soil biological activity, and bioassay to assess nutrient cycling. In line with our expectations, our results evidenced lower Bemisia tabaci densities in tomato crops with grassed than bare inter-rows (P-value = 0.04). In addition, soil biological activity was higher in grassed than bare inter-rows, with a mean increase of 23 and 68% for bean and acacia lamina-baits decomposition, respectively, for all sampling dates. Nonetheless, the biomass produced in bioassay was 31% inferior in soil from grassed than bare inter-rows, which was well reflected by crop yield differences between the two intercropping modalities. These results suggest that while grassed inter-rows may improve soil biological activity and reduce Bemisia tabaci spreading in tomato crop, the resulting soil community may have higher nutritional needs that probably led to competition with tomato growth. We conclude that good biological activity and pest control do not necessarily translate in increased yield in high inputs systems as tomato crops, at least on the short-term