Evaluation of certain Nitrogen-Fixing Bacteria against Fusarium spp. infected peanut

In this study, the inhibition of soil borne pathogenic fungi Fusarium spp. that cause root and pod rot diseases in peanut (Arachis hypogaea) was investigated by using  soil-isolated Plant Growth Promoting Rhizobacteria (PGPR), (Azotobacter and Azospirillum) and root-nodule Brady- Rhizobium as biological agents. Twenty seven isolates of  Azotobacter  and  26 isolates of  Azospirillum obtained from rhizosphere of peanut plants, The efficiency of the nitrogenase activity was estimated and the best four  Azotobacter isolates including (A3, A7, A11, and A20) and three Azospirillum isolates including (AZ2, AZ14 and AZ18) were selected as the most efficient in  nitrogenase activity. These isolates were subjected to test their ability in solubilizing zinc and phosphate and their strength in direct antagonism. The isolates A7 and Az18 were more efficient in solubilizing Phosphate and zinc. Azospirillum sp. AZ18, Azotobacter sp. A7 and Brady-Rhizobium sp. B-Rh1 achieved the highest reduction percentage in mycelia linear growth of pathogenic fungi in vitro. Under greenhouse conditions, Azotobacter sp. A7 recorded the highest disease reduction percentage of peanut root rot (44.38 %). Furthermore, Brady-Rhizobium sp. B-Rh1 recorded the highest disease reduction of peanut pod rot (50.6%) followed by Azotobacter sp. A7 (47.62%). In addition, our results showed that inoculation with the tested nitrogen fixing bacteria gave remarkable increase in the yield parameters of peanut plants such as number and weight of pods and  increased the vegetative biomass overall

Studying The Collector Performance Of Updraft Solar Chimney Power Plant

In the shadow of increasing energy consumption, renewable energy is the best choicefor a sustainable environment. The solar chimney power plant (SCPP) is a new technology, many researchers are paying their attention to improve its performance. In this study, experimental and numerical studies were used to understand the effect of the collector geometry on the SCPP performance. The SCPP prototype under our investigation is installed in Aswan city, its chimney height is 20m, its diameter is 1 m and the collector is a square which has a side length of 28.5m. Three dimensional CFD simulations were made to calculate the temperature and velocity distribution inside two different shapes of SCPP collector. The conclusion is that the square shaped collector achieved higher output power than the circular collector by 7.6 % at the same surface area exposed to solar radiation