Ameliorative effect of Ascorbic acid and biochar on Growth, and antioxidant enzymes on early Seedling of Sorghum under Salinity Conditions

Salt stress is one of the major environmental stresses that limits the growth, antioxidant defense and sustainable crop productivity. A controlled study was done to determine the ameliorative effects of ascorbic acid (ASA) (0, 568, and 850 μM) and biochar (BC) (0, 2 and 4% BC [w/w]) on emergence, growth, and physiological attributes of sorghum grown under three salinity levels (0, 100, and 200 mM NaCl). High salinity stress significantly reduced emergence percentage, emergence rate, shoot length, root length, specific root length, total fresh weight (T.F.W), total dry weight (T.D.W), the activities of peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT), but increased malondialdehyde (MDA) content. At the 200 mM NaCl level, 850 μM ASA with 4% BC enhanced most of the physiological attributes determined. At the 200 mM salinity level, total dry weight of sorghum seedling was increased by 42.7% and 23.1% at 2% and 4% BC levels, respectively as compared with non-BC control. The highest emergence rate at 200 mM NaCl was achieved at 4% BC and 850 μM ASA level. Our study suggested that the combined application of ASA and BC at appropriate amount and concentration on sorghum seedling may be helpful in salt tolerance and getting increase antioxidant enzymes that mitigate harms affected by saline problems worldwide.

Toxicity, Pathogenicity, and Genetic Differentiation of Five Species of Fusarium from Sorghum and Millet

Fusarium isolates recovered from sorghum and millet are commonly identified as F. moniliforme, but with the recognition of new species in this group, the strains given this name are being re-evaluated. We analyzed five strains each from five Fusarium species (F. andiyazi, F. nygamai, F. pseudonygamai, F. thapsinum, and F. verticillioides) often associated with sorghum and millet for their ability to produce fumonisin and moniliformin, their toxicity to ducklings, and their ability to cause disease on sorghum seedlings in vitro. These species can be distinguished with isozymes (fumarase, NADP-dependent isocitrate dehydrogenase, and malate dehydrogenase) and with banding patterns resulting from amplified fragment length polymorphisms. Two species, F. pseudonygamai and F. thapsinum, produced high levels of moniliformin, but little or no fumonisins, and were consistently highly toxigenic in the duckling tests. Two species, F. verticillioides and F. nygamai, produced high levels of fumonisins, but little or no moniliformin, and also were toxigenic in the duckling tests. F. andiyazi produced little or no toxin and was the least toxigenic in the duckling tests. In sorghum seedling pathogenicity tests, F. thapsinum was the most virulent followed by F. andiyazi, then F. verticillioides, and finally F. nygamai and F. pseudonygamai, which were similar to each other. Thus, these five species, which would once have all been called F. moniliforme, differ sufficiently in terms of plant pathogenicity and toxin production profile, that their previous misidentification could explain inconsistencies in the literature and differences observed by researchers who thought they were all working with the same fungal species.