• The Plant Pathology Journal
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• v.24 no.1
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• pp.67-73
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• 2008

Seedling damping-off and bottom rot caused by Rhizoctonia solani are yield limiting diseases of crisphead lettuce. To provide biocontrol measure in the management of the diseases, biocontrol strain Pseudomonas aeruginosa LY-11 was isolated from lettuce rhizosphere and introduced into crisphead lettuce rhizosphere by the seed coating delivery method. Alginate was used as a coating material to generate beads containing $10^6-10^{6.5}$ colony-forming units (CFUs) of viable bacterial cells of LY-11. When seeds germinated from the alginate beads containing the strain LY-11, the bacteria established mostly in plant rhizosphere to maintain at least $10^4$ CFU per gram of plant tissues. Crisphead lettuce seedlings germinated from the entrapped seeds were less affected from damping-off and bottom rot with disease control values of 70.4% and 85.4% respectively. Although P. aeruginosa LY-11 colonized plant rhizosphere and not phyllosphere, the result indicated that bottom rot caused by the foliar inoculation of R. solani was effectively reduced by the rhizobacteria. All data suggested that immobilized rhizobacterial application in seeds by alginate coating could control damping-off and induce induced systemic resistance of crisphead lettuce to reduce bottom rot.

• Korean Journal of Medicinal Crop Science
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• v.7 no.3
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• pp.213-217
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• 1999

Seed coating and pelleting techniques have been used in many crops to improve the germination vigor of tiny and light seeds. Cultivated Chinese-foxglove (Rehmannia glutlnosa) has been infected by various types of virus derived from vagetative propagation of rootstock. Seed characteristics and alginate-coated seed germination rate have been investigated to get basic information for healthy seedling production through seed propagation. Chinese-foxglove showed different numbers of seeds per pod from 61 in Seocheon local to 207 in Jiwhang 1 and 1,000grain weight also varied from 70mg of Seocheon local to 130mg of Jiwhang 1. Seeds of Chinese-foxglove has dormancy because that seed collected last year more stimulated than that of this year at germination test. Optimum alginate concentration for pellected seeds germination was 2%.