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Early diagnosis of seedborne fungal pathogens is particularly important, as often, infected seeds appear symptomless; seed diagnosis can avoid uncontrolled propagation of pathogens through long-distance exchange of such material. This will prevent economic losses and unnecessary use of fungicides, so reducing costs and the introduction of toxic substances into the environment. Traditional techniques for detection of seedborne fungi are based on incubation and grow-out methods. Although these are frequently used because of their simplicity of application, they are time-consuming, require mycological skills, and are sometimes not sensitive enough to low levels of seed infection. Recently, new identification techniques, based on DNA analysis, have been applied and are very efficient due to high sensitivity and specificity. The most common technique is conventional PCR, while other recent techniques include nested PCR, to obviate low levels of target pathogens, multiplex PCR, to detect several pathogens simultaneously, real-time PCR, to quantify fungi on seeds, and magnetic-capture hybridization PCR. The main drawbacks of molecular methods are the inability to distinguish between vital and non-vital inocula, and the difficulty in obtaining quality DNA template, due to PCR inhibitors in seeds. To reduce inhibitory effects, several modified PCR protocols, such as loop-mediated isothermal amplification, and non-destructive testing methods have been developed. Loop-mediated isothermal amplification and next-generation sequencing have been widely applied in nucleic acid analysis and, given the numerous advantages provided, their application can be substantially extended in the future for detection of fungal pathogens in seeds. [ABSTRACT FROM AUTHOR]

Common bean ( Phaseolus vulgaris L.) is one of the most important legume crops for human consumption. However, its grain yield can be reduced by up to 90% by the seedborne disease, anthracnose. Fungicide treatment is costly and time-consuming. The introduction of host plant resistance against this disease appears, therefore, to be crucial for enhancing the productivity of this crop in Kyrgyzstan. The use of DNA-based markers in backcrossing programmes may help speed up the breeding for resistance. In this study, we used a combination of inoculation tests and a DNA marker ( SCAreoli marker) to track the transfer of host-plant resistance ( Co-2 gene) from two donor cultivars, ' Vaillant' and ' Flagrano', to susceptible Kyrgyz cultivars ' Ryabaya', ' Kytayanka' and ' Lopatka', which are widely grown in the country. The segregating offspring were evaluated to test the reliability of the SCAreoli marker as selection aid for host-plant resistance to anthracnose. Our study showed that a co-dominant DNA marker can successfully be used in backcross breeding to distinguish segregating material in different market classes of common bean. [ABSTRACT FROM AUTHOR]

Specific scope This standard describes the conduct of trials for the efficacy evaluation of fungicidal seed treatments against seedling diseases (under controlled conditions). Specific approval and amendment First approved in 1987-09. Revision approved in 1999-09. Revision approved in 2012-09. [ABSTRACT FROM AUTHOR]

Treatment of seeds with an aqueous extract of yucca (YE), Yucca schidigera, was evaluated for antifungal activity against seedborne pathogens as well as its effect on seed germination and seedling growth of sorghum ( Sorghum bicolor). The antifungal effect of YE was observed against Leptosphaeria sacchari (syn. Phoma sorghina) when the extract was applied at 2·5 and 10% concentrations. At 10% concentration, YE significantly reduced not only the incidence of L. sacchari, but also that of Fusarium spp., Cochliobolus lunatus (syn. Curvularia lunata) and Cladosporium spp. The effect of 10% YE on seedborne fungi was broader than the fungicide fludioxonil, particularly with regard to Fusarium. Furthermore, the number of normal, healthy-looking seedlings increased in a dose-responsive manner with YE treatment. Seedling vigour was also stimulated by YE but no correlation was observed with the concentrations tested. Under glasshouse conditions, the treatment of seeds with 10% YE increased the emergence of seedlings and plant height and reduced the number of seedlings with crown rot compared to negative controls and saponin. The positive effect was similar to the effect obtained with fungicide-treated seeds. Treatment of seeds with synthetic saponin inhibited seedborne fungi less effectively and also negatively affected germination and vigour of the seedlings, compared to the treatment with YE. The results demonstrate an agronomic potential for the use of YE as a biofungicide for seed treatment of sorghum. The difference between the antifungal and the vigour-stimulating effects of YE warrants further investigation. [ABSTRACT FROM AUTHOR]

The objectives of this study were to identify the fungi associated to carrot seeds from Montecristo, Córdoba in Argentina and to determine the efficiency of the chemical seed treatment to control fungi and check the effect of this treatment on the physiological quality of the seeds. Seed health and physiological tests were carried out. The effect of fungicide combined treatments was evaluated considering the different doses and time of seed immersion. High incidence of associated fungi was observed with prevalence of Alternaria alternata, Fusarium sp. and Epicoccum sp. Seed germination and vigor levels were closely related to the levels of fungal incidence. The fungicidal treatments reduced the percentage of contaminated seeds and their effects depended mainly on the time of seed immersion. The most efficient treatments were obtained with Tebuconazole, Tiram and Carboxin+Tiram at doses of 1.000 and 500 ppm a.i. applied by immersion for one hour. These treatments also induced increase in the germination percentages of carrot seeds under these study conditions. [ABSTRACT FROM AUTHOR]

The incidence of Phoma ligulicola in Tasmanian pyrethrum seed and methods of managing seedborne mycoflora were determined. Fourteen different fungi were regularly isolated from seed, including Alternaria tenuissima, Stemphylium botryosum, and P. ligulicola, which have been documented as pathogens of pyrethrum. Comparisons between the incidence of these fungi from seed surface-sterilized with sodium hypochlorite and nontreated seed indicated they occurred both within and on the outside of the seed. A polymerase chain reaction (PCR) test for the detection of P. ligulicola was also developed, with a detection limit of 800 fg of fungal DNA. The assay detected infested seed lots down to an incidence of 0.5%. Reliable amplification of the target DNA was achieved with the addition of bovine serum albumin to reduce the influence of inhibitors from pyrethrum seed. Agar plate tests and PCR demonstrated variability with pyrethrum cultivars in the presence and viability of P. ligulicola in seed. Effective management strategies for the reduction of seedborne P. ligulicola included the regular use of fungicides for reducing foliar disease intensity in the seed fields prior to harvest. Seed treatments with fludioxonil and thiabendazole/thiram also significantly reduced the incidence of seedborne P. ligulicola and increased seed germination and seedling survival. [ABSTRACT FROM AUTHOR]

Presents a study that examined the aqueous moringa seed extract (AMSE) as a seed treatment biofungicide for groundnuts in Nigeria. Information on moringa oleifera; Prevalence of fungi on groundnut seeds; Effect of AMSE on seed-borne fungi.