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Clove oil, clove extract and butylated hydroxyanisole (BHA) completely suppressed the growth of both Fusarium verticilloides and Aspergillus flavus isolates. Black cumin and thyme extracts were more suppressive on F. verticilloides than A. flavus. Antitox-Plus (AP) had no effect on the growth of both the pathogens. The minimum inhibitory concentration (MIC) test revealed that A. flavus was more sensitive to Fix-A-Tox (FAT) and AP than F. verticilloides. In the growth media, all the tested substances, completely suppressed the production of aflatoxins by A. flavus and significantly reduced fumonisins production by F. verticilloides, particularly clove oil and extract. Treatment of immature grains with the tested mould inhibitors prior to inoculation with A. flavus and F. verticilloides significantly reduced mycotoxins production at the end of the storage period; moreover, highest reduction rates were realised by BHA and FAT. Complete or highly significant suppression of aflatoxins in mature grains were obtained by all the tested herbal and synthetic mould inhibitors. Ground clove buds contained the highest carvacrol content, whereas thymol content was higher in thyme extract. Clove oil was rich in eugenol. Alpha-tocopherol content was higher in ground black cumin (BC), followed by BC oil. Unsaturated fatty acid content was higher in thyme extract and ground BC than saturated fatty acids. Linolenic acid was the most predominant fatty acid in BC oil and extract, whereas behenic and arachidic acids were detected only in BC oil. Stearic acid was the main fatty acid in clove oil and extract, whereas oleic acid was the prevailing fatty acid in thyme extract.

Natural infected broad bean seeds were collected from Noubaria region during the season of 2012-2013. The isolated and purified fungi from these seeds were identified as: Alternaria alternata, Penicilliun citrinum and Aspergillus flavus. Occurrence frequencies of the isolated fungi were 75.76, 15.16 and 9.08%, respectively. Toxin production potentials of Alternaria alternata and P. citrinum isolates, as estimated by Plug Agar method, were 231.00 and 337.00 µ.g/g, respectively., whereas, A.flavus isolate was unable to produce aflatoxins. Sorbic and benzoic acids were proved to be more effective in reducing fungal growth of A. alternata and P. citrinum than metalaxyl and ridomyl fungicides. A. alternata was less sensitive to sorbic acid than benzoic acid. All the tested treatments, at their MICs, significantly reduced growth of A. alternata growth and alternariol (AOH) production; however, higher efficiency ratio (99.860%) was realized by benzoic acid. Similar inhibition of growth and citrinin (CTN) production was induced by P. citrinum. Metalaxyl was less efficient in inhibiting AOH and CTN than the other tested treatments. Soaking seeds in water significantly raise the efficiency of mycotoxins production in all the tested seed treatments. Moreover, efficiency of benzoic and sorbic acids in reducing AOH and CTN production was higher during soaking process. Seeds inoculated with the tested pathogens, then treated with sorbic or benzoic acid appeared healthy with normal color, texture and morphology.

An environmental problem was recorded in broad bean crop cultivated in Noubareya region during season 2013. Harvested broad bean seeds were obtained by satisfactory evidence of weak economic value.An attempt of seed treatment process was carried out in this study to inhibit fungal growth and mycotoxins produced by Alternaria alternata and Penicillium citrinum in field during cultivation process using sorbic and benzoic acids at 10 and 15 ppm,; ethyl sorbate and/or ethyl benzoate at 5 and10 ppm for each treatment as alternative to the fungicides metalaxyl DS and ridomil MZ72WP at recommended rate (x) and 1 ½ recommended rate applied for seed protection during cultivation process. The germination test showed the failure of all the tested preservative treatments to germinate seeds. Therefore; all treatments were used as foliar seedlings spray applied 3 times every 15 days during the experiment (60 days) . The results of fungicidal activity indicated that the use of preservative up to 10 ppm totally inhibited fungal growth except ethyl benzoate and ethyl sorbate which completely inhibited fungi at 5ppm Moreover, 5 and 10 ppm concs realized the same inhibition rate exerted by metalaxyl and ridomil MZ at 1.5 x. Untreated plants showed higher death ratios, compared with treated ones. Ridomil MZ at conc. 1.5 x reduced dead plants 60% followed by benzoic acid 56% at conc.5 ppm.Furthermore, the ester form of both benzoic and sorbic acids were more effective in reducing AOH and CTN than the other tested fungicides. metalaxyl and ridomil MZ at 1.5 x. Ridomil MZ at conc. 1.5 x reduced dead plants 60% followed by benzoic acid 56% at conc.5ppm. Furthermore, the ester form of both benzoic and sorbic acids acids were more effective in reducing altrnariol (AOH) and citrinin (CTN) than the other tested fungicides. Accordingly they can act successfully as fungicides alternatives. Benzoic acid has been actively playing a great role as antifungal and detoxifier agent. Meanwhile, it affected plant growth which badly in need for more studies to avoid these side effects.