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Soil management techniques influence the biological and physicochemical properties of the soil and lead to changes in soil quality and cover and thus on crop profitability and yield. In this study, the effects of short-term tillage and no-tillage methods combined with a chemical treatment using Glyphosate on weed abundance, selected soil physical properties and yield components were evaluated in durum wheat under Mediterranean climatic conditions. The no-tillage (NT) treatment resulted in higher weed community density during wheat cultivation and moisture consumption than the conventional tillage treatment. The tillage practice and the application of Glyphosate showed a very high efficiency on weeds. Furthermore, the results obtained showed a significant variation and effect of the treatments on the soil characteristics. The application of the no-tillage technique induced a small increase in soil moisture at the seed germination stage (25.6%), while at the last sampling a small increase was recorded in the CT treatment (9.5% for CT and 8.8% for NT). The results of the soil porosity, showed during the whole test period high values in the conventional technique (with or without herbicide application); but for the resistance to soil penetration, the results showed higher values in the no-till technique. Finally, the effect of the tillage system on crop yield was evaluated. In our study, the results showed that significant increases in the number of heads per m2 (351.3 heads per m2), the number of grains per head (45.8) and the weight of 1,000 grains (41.2 g) were obtained with the tillage treatment combined with glyphosate application. When comparing the two tillage methods, the highest values were always revealed with the tillage technique. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the occurrence of mycorrhizal fungi and glomalin content in soil under different cover crops with and without the application of nitrogen in the cover. The following cover plants were used: Crotalaria juncea (Crotalaria juncea L.), wild beans from Ceará (Canavalia brasiliensis Mart. ex Benth.), Guandú 'BRS mandarin' [Cajanus cajan (L.) Millsp.], millet 'BR05' [Pennisetum glaucum (L.) R.Br.] and sorghum 'BR 304' [Sorghum bicolor (L.) Moench]. The absolute control of the experiment was the treatment without the use of cover crops, that is, the vegetation of spontaneous occurrence in the area. The experimental design was randomized blocks in subplots with three replications. Spore density, mycorrhizal colonization rate, easily extractable glomalin, and species present in the rhizosphere of the cover crops were determined. No differences were found in the diversity of mycorrhizal fungi associated with the different cover crops studied or in the values of spore density, root colonization, or glomalin content. Nitrogen application did not influence the mycorrhizal activity in the investigated cover crops. The most frequent species associated with cover crops were Scutellospora pellucida and Scutellospora persica in C. juncea; Gigaspora sp. on Sorghum; Glomus macrocarpum in Guandu; G. macrocarpum and Glomus clavisporum in millet; and Glomus microaggregatum and Glomus tortuosum in Spontaneous Vegetation. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the occurrence of mycorrhizal fungi and glomalin content in soil under different cover crops with and without the application of nitrogen in the cover. The following cover plants were used: Crotalaria juncea (Crotalaria juncea L.), wild beans from Ceará (Canavalia brasiliensis Mart. ex Benth.), Guandú ‘BRS mandarin’ [Cajanus cajan (L.) Millsp.], millet ‘BR05’ [Pennisetum glaucum (L.) R.Br.] and sorghum ‘BR 304’ [Sorghum bicolor (L.) Moench]. The absolute control of the experiment was the treatment without the use of cover crops, that is, the vegetation of spontaneous occurrence in the area. The experimental design was randomized blocks in subplots with three replications. Spore density, mycorrhizal colonization rate, easily extractable glomalin, and species present in the rhizosphere of the cover crops were determined. No differences were found in the diversity of mycorrhizal fungi associated with the different cover crops studied or in the values of spore density, root colonization, or glomalin content. Nitrogen application did not influence the mycorrhizal activity in the investigated cover crops. The most frequent species associated with cover crops were Scutellospora pellucida and Scutellospora persica in C. juncea; Gigaspora sp. on Sorghum; Glomus macrocarpum in Guandu; G. macrocarpum and Glomus clavisporum in millet; and Glomus microaggregatum and Glomus tortuosum in Spontaneous Vegetation.