Seed Health Testing For Nine Cultivars of Sorghum bioclor L. in Gadarif Area

Abstract

This study was conducted in both laboratories of plant pathology and tissue culture in College of Agricultural Studies, Sudan University Science and Technology Nine cultivars of Sorghum bicolor collected from Gadarif area were tested for the presence of seed borne fungi. The cultivars were Mugudahmer, Wadahmed, Wadakar. Arfaagadamac, Hageen, Tetron, Dabar, Fatarita and Tabet. Seed health testing included dry inspection in which the seeds were divided into healthy, broken and infected. Seeds were germinated on moistened medical cotton in sterilized plastic petridishes and as well seeds were plated on moistened filter paper and incubated at 25o C . Seven fungi were isulated,purified and identified . These were; Drechslera spicifer, Macrophomina phaseolina, Fusarum oxysporum, Penicillum digitatum, Spergillus flavus,Aspergillus niger, Rhizopus nigricans. Pathogenicity test was carried out for four fungi these were Drechslera spicifer, Macrophomina phaseolina, Fusarum oxysporum, Penicillum digitatum. The results revealed that the symptoms produced from artificial inculcations were seed rot bre-and post- emergence damping off as well leaf spots. The fungi Macrophomina phaseolina, recorded the highest incidence 26.6% in cultivars Wad ahmed and the least incidence 6.6% in cultivars X Hageen. Wad ahmed and Arfaagamac the highest bos- emergence damping off was 40% in cultivar Daber and the least incidence 20% in cultivars Wad ahmed. Wad akar and Arfaa gadamac. For symptoms development the highest Arfaa gadamac 26.6% and the least incidence was 6.6% in cultivars Daber and Fatarita. For Drechslera spicifer, the highest incidence for seed rot and pre- emergence damping off was 33.3% for Wad akar arfaaga gadmac and the least incidence in cultivars Daber For symptoms development the highest incidence was 20% in Wad ahmed, Arfaagadamac Fatarata, Tabet and the least incidence was 6.6% in cultivar Daber. For Fusarum oxysporum the highest pre emergence damping off was33.3% in cultivars Tabet, Tetron, Hageen, Wadahmed and Arfaa gadamac And the least was 13.3% in cultivar Daber The highest post emergence damping off was 40 in Daber and the least incdence13.3% in cultivars Mugud ahmer, Hageenand Daber. For symptoms development the highest in cultivars Wad Ahmed 33.3% and the least mdence was 13.3% in cultivars Daber Hageen and Nugud ahmer. XI For Penicillum digitatum the highest of seed rot 40 in cultivars Arfaa gadmac, Tetron and the least incidence was 20% in Hageen Wad Ahmed Fatarita the percentage of post emergence damping off was 26.6% in Wad Ahmed Fatarita Hageen and the least 6.6% in Arfaa gadamac and Tetron. For symptoms development the gighest in Tetron 33.3% and the lest incidence was 6.6% in cultivars Fatarita.