الفهرس 
INTRODUCTION
Seed borne fungi associated withsoybean seedsOnly 14 pages are availabe for public view
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Abstract
Soybean seed borne pathogenic fungi caused a world problems to soybean production. It cause a lack of seed quality and seeds failed to germinate or seedling and plants developed. For this, the present work was planned to study these problems and gave some practical methods to solve or avoiding the loses of it. The obtained results can be summarized as follows:
1. Ten genera with 12 species of fungi were isolated from seeds of six soybean cultivars (Giza 21, Giza 22, Giza 35, Giza 82, Giza 83 and Giza 111) which obtained from Plant Pathology Research Institute Agric. Res. Center, Giza, Egypt, from growing season 2012. These fungi were Fusarium semitectum, F. verticillioides, Pochonia chylamydosporia, Alternaria alternata, Chaetomium globosum, Macrophomina phaseolina, Aspergillus flavus, A. niger, Penicillium purpurogenum, Trichoderma horzianum, Eurotium amstelodami and Syncephalastrum racemosum. A. flavus, F. semitectum and F. verticillioides isolated from soybean seeds with high frequency while E. amstelodami and S. racem disappeared in seeds of all tested cultivars except cv. Giza 22 which isolated with low frequency. Other fungi isolated with intermediate frequency.
2. from sixty-four major isolates tested for their pathogenicity, 61 isolates caused soybean pre- and post-emergence damping-off. All genera of Fusarium, Alternaria, Pochonia, Chaetomium except isolate of F. semitectum No. 6 were virulent, while isolates of Macrophomina phaseolina did not affected percentage of damping-off. The pathogenic isolates varied for its virulent from high to moderate to weak pathogen to soybean damping-off.
3. F. semitectum, F. verticillioides, A. alternata, M. phaseolina and A. flavus were isolated from all seed parts (seed coat, cotyledon and embryo) of soybean seeds obtained from infected with F. semitectum or non infected soybean plants except one case of M. phaseolina which not isolated from embryo of seeds obtained from non infected plants. There were non-significant differences between frequencies of isolated fungi and the seed parts and between seeds obtained for infected and non infected plants.
4. Storing seeds from 4 to 8 months at 5°C not affected frequency % of F. semitectum, M. phaseolina and A. alternate, increased frequency % of A. flavus and A. niger and decreased frequency % of F. verticillioids.
- Frequency % of F. semitectum, A. flavus, M. phaseolina and A. alternata increased when seeds stored at 35°C for 8 months than 4 months and decreased in case of F. verticillioides and A. niger.
- Storage period from 4 to 8 months at 25°C not affected frequency % of F. semitectum and F. verticillioides and increased frequency % of M. phaseolina, A. alternata and A. niger.
- Storing seeds at 25°C for 4 months gave the highest percentage of seed germination (70%) while storing seeds at 5°C gave the lowest percentage of seed germination.
- Increasing storage period from 4 to 8 months with all tested temperatures decreased percentage of seed germination.
- Percentage seed content of protein decreased when seeds stored for 8 months at 25 and 35°C and not affected when seeds stored at 5°C.
- Percentage of oil was decreased when seeds stored for 8 months than 4 months in temperature of 5 and 25°C and not affected when seeds were stored at 35°C.
- Percentage of fatty acids increased when seeds stored for 8 months