Plant essential oils have the potential to replace the synthetic fungicides in the management of postharvest diseases of fruit and vegetables.The aim of this study was to access the in vitro and in vivo activity of essential oil obtained from oregano (Origanum vulgare L. ssp. hirtum), thyme (Thymus vulgaris L.) and lemon (Citrus limon L.) plants, against some important postharvest pathogens (Botrytis cinerea, Penicillium italicum and P. digitatum). In vitro experiments indicated that P. italicum did not show any mycelium growth in presence of thyme essential oils at concentration of 0.13 μl/ml. Moreover, B. cinerea did not show any mycelium growth in presence of lemon and oregano essential oils at concentration of 17 μl/ml and 0.02 μl/ml, respectively. Moreover, the essential oils from three species were effective in reducing the spore germination. The in vivo experiments confirmed the strong efficacy shown in vitro by essential oils. These oregano and lemon oils were very effective in controlling disease severity of infected fruit by B. cinera in tomatoes, strawberries and cucumbers. In tomatoes, grey mould due to B. cinerea was completed inhibited by oregano essential oils at 0.30 μl/ml. Moreover, lemon essential oils induced a significant reduction of grey mould disease severity. In strawberries, grey mould was completed inhibited by lemon essential oils at 0.05 μl/ml. In addition, lemon essential oils at 0.05 μl/ml showed 39% reduction of infected cucumber fruits by B. cinerea. These results indicate that essential oils after suitable formulation could be used for the control of postharvest diseases caused by Botrytis and Penicillium pathogens.

The use of plant growth promoting bacteria (PGPB) as biostimulants favors the increase of crop productivity and the improvement of yield quality. The main objective of the present study was to investigate the effect of the PGPB biostimulants (Azotobacter chroococcum, Bacillus subtilis, Bacillus megatherium and their mixes) and the application method (foliar and soil) on the growth, the physiology, the yield and the quality of maize. The obtained results showed that A. chroococcum treatment increased the chlorophyll content up to 6.1%, the photosynthetic rate up to 18.4% and the transpiration rate up to 34.3%. The highest maize yields were performed by the treatments B. megatherium (244.67 g) and the mix of A. chroococcum and B. subtilis (1:1) (243.67 g) when applied on the soil. The Soil application of the PGPB resulted in increased yield of maize from 5.5 to 13.4% compared to control treatment. Concerning quality characteristics, B. subtilis treatment increased total solids content in harvested maize seeds by 92%, as well as crude fiber content by 46% compared to control. The results confirmed that the use of PGPB could contribute as a new cultivation practice for sustainable growth, productivity and quality of grain crops.

In organic agriculture, intercropping is receiving increasing attention as it offers potential advantages for increasing sustainability in crop production. However, intercropping can increase competition between crops and weeds. In this study, we analyzed the effects of maize–legume intercrops on the weed community in an organic cropping system. We were concerned only with competition between crops and weeds for light. We recorded a statistically significant negative correlation between the fraction of photosynthetically active radiation (F _int PAR) intercepted by the canopy, and both weed density and weed dry matter. Maize–legume intercropping led to a higher soil canopy cover (leaf area index) than sole crops. The lowest values for F _int PAR were received in sole crops. Thus, in maize–legume intercrops the decrease in available light for weeds led to a reduction of weed density and dry matter, compared to sole crops. Intercropping maize and legumes considerably reduced the weed density in the intercrop compared with the maize pure stand. Weed suppression by crops was also greater on a low-productivity site than on a high-productivity site. Our results indicate that intercropping could be useful for weed suppression in organic row-crops such as maize and cotton.

Nitrogen (N) management remains a global challenge for the sustainability of diversified farming systems. Field crops are often over-supplied with nitrogen by farmers aiming to high productivity. Although the increase of nitrogen rates leads in many instances to high yields, degree of effectiveness for nitrogen use remains low. Urease and nitrification inhibitors are technologies which have been present in the fertilizers market at least 50 years. Inhibitors exploitation ensures long-term nitrogen release and improved N-uptake by plants and N-storage in seeds and silage. Avail of inhibitors, such as the decline of nitrogen leaching in form of NO₃⁻, reduction of emissions in NH₃ form, and rise of yield, are some of the desirable attributes that are derived from their integration in fertilization schedules. This review reports the evaluation of applied nitrogen, with inhibitors, and field crops based on nitrogen indices. The examined N-indicators include Nitrogen use efficiency (NUE), Nitrogen Utilization Efficiency (NUtE,) Nitrogen Agronomic Efficiency (NAE), Nitrogen Harvest Index (NHI), and N uptake. This review gathered all, to the best of our knowledge, available data regarding the utilization of nitrification and urease inhibitors under an exclusively agronomic perspective. Either dual or single use of nitrification and urease inhibitors has been reported to significantly increase yield components and promote nitrogen uptake. To conclude, the assessment of N-related indices is vital to promoting sustainability in diversified farming systems, while the integration of inhibitors in national N fertilizations schemes may contribute to system profitability through enhancement of N-supply to crops.