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Pest management
Nematode Suppressive Crops Featured
Plant parasitic nematodes are destructive, hard-to-control soil pests of vegetables, annual flowers, woody ornamentals, and many row crops. Southern and peanut rootknot nematodes are the two most common nematode pests. Control practices for these and other damaging nematodes have largely focused on yearly nematicide treatments. However, nematicides for home and farm use may not be available in the future, so environmentally sound control practices may have to be used to effectively manage these damaging pests.
Impact of soil health management practices on soilborne... Featured
Various cultural practices, including the use of cover and rotational crops, composts, tillage systems, and others have been promoted as management options for enhancing soil quality and health. All cultural practices are known to directly or indirectly affect populations of soilborne pathogens and the severity of their resultant root diseases. Soil biology is a major component and contributes significantly to soil quality and productivity. The major activities of soil microbes include the decomposition of organic materials, mineralization of nutrients, nitrogen fixation, suppression of crop pests and protection of roots, but also parasitism and injury to plants. Thus, there is a great need to assure that the introduced soil management practices to improve soil quality will also result and maintain a healthy soil. The latter include the abundance and diversity of total soil microbes, high population of beneficial organisms and low population and/or activities of crop pests. Production of vegetables and ot ...
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Sustainable pest regulation in agricultural landscapes:... Featured
Agricultural intensification has resulted in a simplification of agricultural landscapes by the expansion of agricultural land, enlargement of field size and removal of non-crop habitat. These changes are considered to be an important cause of the rapid decline in farmland biodiversity, with the remaining biodiversity concentrated in field edges and non-crop habitats. The simplification of landscape composition and the decline of biodiversity may affect the functioning of natural pest control because non-crop habitats provide requisites for a broad spectrum of natural enemies, and the exchange of natural enemies between crop and non-crop habitats is likely to be diminished in landscapes dominated by arable cropland. In this review, we test the hypothesis that natural pest control is enhanced in complex patchy landscapes with a high proportion of non-crop habitats as compared to simple large-scale landscapes with little associated non-crop habitat. In 74% and 45% of the studies reviewed, respectively, natu ...
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Nematode succession and microfauna–microorganism inte... Featured
The quality of plant material affects the vigor of the decomposition process and composition of the decomposer biota. Root residues from hairy vetch (Vicia villosa Roth), rye (Secale cereale L.) and vetch+rye, packed in litterbags were placed in pots of soil at 15 C and the content of the bags was analyzed after 2, 4, 8 and 12 weeks. Bacterial biomass did not differ between residues with contrasting composition. Among bacterivores groups of nematodes that require high bacterial production dominated in fast decomposing resources whereas flagellates with smaller requirements prevail in slower decomposing resources. Biomass of bacterial feeding nematodes correlated positively with early phase (0–2 wk) decomposition that increased in the order: rye< vetch+rye<vetch. Bacterial biomass therefore seems to be under top–down (predation) control during early decomposition. In contrast, the fungal biomass differed between resources with highest values for rye. Moreover, this increase in fungal biomass occurred l ...
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Semis direct et résistance des cultures aux maladies Featured
Les relations "génotypes - facteurs du milieu" ont toujours constitué un pôle d'intérêt majeur, exercé une véritable fascination pour la recherche, mais les relations plante-parasite sont complexes interviennent en effet, en interaction, les facteurs génétiques (résistance variétale) le cycle physiologique de la plante, le photopériodisme, le climat, la nature du sol, la fertilisation et enfin les incidences des pesticides sur la physiologie de la plante. L'homme peut cependant, agir de manière efficace par sa gestion des systèmes de culture, sur la plupart des facteurs du milieu qui conditionnent la santé des cultures. Avec les techniques de semis direct qui ont été développées et ont donné naissance à de multiples systèmes de production de grains, intégrant ou non l'élevage, la gestion des facteurs du milieu a radicalement changé au Brésil au cours des 25 dernières années, sur des surfaces considérables (plus de 10 millions d’hectares sont en semis direct en 1999) ; outre ...
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