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Root rot of alfalfa caused by Rhizoctonia solani is considered one of the most important diseases, which annually occurred in many plants and causes great losses in yield production. So the present study aimed to find the best strategy to control or at least reduce disease severity. The Results showed that the fungal isolates were identified by using the morphological features of mycelia as R. solani. Effect of certain antagonistic bio-agents fungi to inhibit the growth of R. solani has been studied under laboratory. In general isolate No. 2002, followed by 2008 and 2004, which recorded (60.5, 47.2and 33.1%), respectively In this respect, the highest inhibition of R. solani growth was occurred by isolate No.5001, followed by 5007 and 5009, 5002, which recorded (54.56, 449.39, 46.26 and 46.26 %), respectively. Eight bacterial strains were tested against growth of Rhizoctonia sp was investigated in vitro. demonstrated that all tested bacteria significantly inhibited growth of Rhizoctonia sp in vitro the highest inhibition of R. solani growth was occurred by isolate No.1001, followed by 1016 and 1010, which recorded (59.25, 52.76 and 47.16 %), respectively. While, the least inhibition of Rhizoctonia growth was occurred by isolate No.1009, which recorded (31.47%). Ten yeast strains were tested against growth of the pathogen were investigated in vitro demonstrated that all tested yeast significantly inhibited growth of the pathogen in vitro. In conclusion, we could say that Biocontrol agents could be used as an eco-friendly approach to effectively control the disease and may be advised to the farmers for profitable organic farming. [ABSTRACT FROM AUTHOR]

Alzanzalakhet, Melia azedarach L. (Sapindales: Meliaceae) is a common medicinal plant which is found in Hail desert in Saudi Arabia and traditionally used for various purposes. In this study, toxin effectiveness of the ethanolic, acetonic, and aqueous extracts of M. azedarach leaves was tested to determine a larvicidal activity against the cucurbit fly, Dacus ciliatus (Loew) (Diptera: Tephritidae). Different treatments with M. azedarach extracts varied significantly in their impact on mortality of D. ciliatus larvae. Results showed that all tested extracts in the three solvents exerted a positive pattern for reducing larvae of D. ciliatus. However, the ethanolic M. azedarach extract was the most potent compared with other tested solvents. The highest mortality of the D. ciliatus larvae was shown to be 94%, 74%, and 68% when the concentration was 1 × 105 ppm for ethanolic, acetonic, and aqueous extracts, respectively. In contrast, the concentration 1 × 101 ppm resulted in the lowest mortality of D. ciliatus larvae at 40%, 34%, and 12% for ethanolic, acetonic, and aqueous extracts, respectively. Overall, the results of this study suggest that the ethanolic extract of M. azedarach leaves may be used as a sustainable method for controlling D. ciliatus larvae. [ABSTRACT FROM AUTHOR]