Impact of direct seeding on soil water retention in semi-arid area (region highlands of western Algeria)

This investigation is falls within the framework of conservation agriculture. Indeed, twentyfive years after the first of zero tillage farming experiences, this new method was named crop conservation agriculture because it helps preserve soil nutrients, water absorption enhancing and infiltration and biodiversity by maintaining the natural equilibrium in the soil. The objective of this is study is to compare the impact of the tillage (conventional work and the direct sowing) on water properties of the soil, especially the water-holding capacity of the soil in semi-arid zone (case of Tiaret region). According to the results, the comparative analysis between the two types of tillage (direct drilling sowing and conventional tillage) shows that water parameters studied such as moisture equivalent (He), of holding capacity (Cr), wilting point (Pf) and AWR (UK) are higher in the useful reserve case of direct seeding than in the case of conventional labor.Keywords: Conservation agriculture, direct sowing, conventional labor, soil moisture, holding capacit

Behavior of cereal’s varieties in the presence of Heterodera avenae woll (heteroderidae, tylenchida) cyst nematode in Tiaret Area (Algeria)

The behaviour of cereals varieties (Ofanto, Waha and Vitron for durum wheat; Anza and HD1120 for bread wheat and Saida with Acsad for barly) were tested towards Heterodera avenae. The analysis of the variance reveals that the nematode has an effect on the development of durum wheat for the number of ear per seedling and the weight of thousand seeds, with respectively: P = 0, 0033 and P = 0,000, for the infested varieties and the witnesses. Common wheat shows a highly significant difference (P= 0, 0000) for the varieties infested and pilot and of the same for the barley, but with a significant difference with: P= 0,0002, between the varieties of barley. The two varieties of barley were different when with the weight from 1000grains. The ACP of any species confers that Saida is the most sensitive variety followed by Ofanto and Anza to attack of this nematode.Keywords: Nematode; Heterodera; cereals; varieties; behaviou

EFFETS DU TRAVAIL DU SOL SUR LE COMPORTEMENT PHYSIQUE ET BIOLOGIQUE D’UN SOL SOUS UNE CULTURE DE LENTILLE (LENS EXCULENTA) DANS LA RÉGION DE TIARET ALGÉRIE

Soil management practices influence soilphysical and chemicalcharacteristics and bring about changes in the soilmicrobialcommunity structure and function. In thisstudy, the effects of conventional and no-tillage practices on microbialcommunity structure, selectedphysicochemicalpropertiesweredetermined in a continuous corn system on a silt loamsoil. The no-tillage treatmentresulted in highersoilcarbon and nitrogen contents, viable microbialbiomass, at the 0– 25 cm depththan the conventional tillage treatment. Soilmicrobialcommunity structure assessed,using indicative of fungi, bacteria, in the no-till surface soil. Results of principal components analysisbased on soilphysicochemical in agreement. Theseresultsindicatethat tillage practice and soildepthweretwo important factorsaffectingsoilmicrobialcommunity structure and activity, and conservation tillage practices improvebothphysicochemical and microbiologicalproperties of soil