Score: 3.00 | Title: Evaluation of bacteria isolated from rice for plant growth promotion and biological control of seedling disease of rice .
| Author: Adhikari TB Joseph CM Yang G Phillips DA Nelson LM .
| Journal: Can .
J Microbiol .
Citation: V : 47 ( 10 ) P : 916-24 Year: 2001 Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub11718545 Accession (PMID): 11718545 | Abstract: Of 102 rhizoplane and endophytic bacteria isolated from rice roots and stems in California , 37% significantly ( P < or = 0 . 05 ) inhibited the growth in vitro of two pathogens , Achlya klebsiana and Pythium spinosum , causing seedling disease of rice .
Four endophytic strains were highly effective against seedling disease in growth pouch assays , and these were identified as Pseudomonas fluorescens ( S3 ) , Pseudomonas tolaasii ( S20 ) , Pseudomonas veronii ( S21 ) , and Sphingomonas trueperi ( S12 ) by sequencing of amplified 16S rRNA genes .
Strains S12 , S20 , and S21 contained the nitrogen fixation gene , nifD , but only S12 was able to reduce acetylene in pure culture .
The four strains significantly enhanced plant growth in the absence of pathogens , as evidenced by increases in plant height and dry weight of inoculated rice seedlings relative to noninoculated rice .
Three bacterial strains ( S3 , S20 , and S21 ) were evaluated in pot bioassays and reduced disease incidence by 50%-73% .
Strain S3 was as effective at suppressing disease at the lowest inoculum density ( 106 CFU/mL ) as at higher density ( 10 ( 8 ) CFU/mL or undiluted suspension ) .
This study indicates that selected endophytic bacterial strains have potential for control of seedling disease of rice and for plant growth promotion . | Matching Sentences: [ Sen. 2, subscore: 1.00 ]: Four endophytic strains were highly effective against seedling disease in growth pouch assays , and these were identified as Pseudomonas fluorescens ( S3 ) , Pseudomonas tolaasii ( S20 ) , Pseudomonas veronii ( S21 ) , and Sphingomonas trueperi ( S12 ) by sequencing of amplified 16S rRNA genes . [ Sen. 3, subscore: 1.00 ]: Strains S12 , S20 , and S21 contained the nitrogen fixation gene , nifD , but only S12 was able to reduce acetylene in pure culture . [ Sen. 5, subscore: 1.00 ]: Three bacterial strains ( S3 , S20 , and S21 ) were evaluated in pot bioassays and reduced disease incidence by 50%-73% .
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Score: 3.00 | Title: A mitogen-activated protein kinase cascade regulating infection-related morphogenesis in Magnaporthe grisea .
| Author: Zhao X Kim Y Park G Xu JR .
| Journal: Plant Cell Citation: V : 17 ( 4 ) P : 1317-29 Year: 2005 Type: ARTICLE | Literature: oryza Field: abstract Doc ID: pub15749760 Accession (PMID): 15749760 | Abstract: Many fungal pathogens invade plants by means of specialized infection structures called appressoria .
In the rice ( Oryza sativa ) blast fungus Magnaporthe grisea , the pathogenicity mitogen-activated protein ( MAP ) kinase1 ( PMK1 ) kinase is essential for appressorium formation and invasive growth .
In this study , we functionally characterized the MST7 and MST11 genes of M grisea that are homologous with the yeast MAP kinase kinase STE7 and MAP kinase kinase kinase STE11 .
Similar to the pmk1 mutant , the mst7 and mst11 deletion mutants were nonpathogenic and failed to form appressoria .
When a dominant MST7 allele with S212D and T216E mutations was introduced into the mst7 or mst11 mutant , appressorium formation was restored in the resulting transformants .
PMK1 phosphorylation also was detected in the vegetative hyphae and appressoria of transformants expressing the MST7 ( S212D T216E ) allele .
However , appressoria formed by these transformants failed to penetrate and infect rice leaves , indicating that constitutively active MST7 only partially rescued the defects of the mst7 and mst11 mutants .
The intracellular cAMP level was reduced in transformants expressing the MST7 ( S212D T216E ) allele .
We also generated MST11 mutant alleles with the sterile alpha motif ( SAM ) and Ras-association ( RA ) domains deleted .
Phenotype characterizations of the resulting transformants indicate that the SAM domain but not the RA domain is essential for the function of MST11 .
These data indicate that MST11 , MST7 , and PMK1 function as a MAP kinase cascade regulating infection-related morphogenesis in M grisea .
Although no direct interaction was detected between PMK1 and MST7 or MST11 in yeast two-hybrid assays , a homolog of yeast STE50 in M grisea directly interacted with both MST7 and MST11 and may function as the adaptor protein for the MST11-MST7-PMK1 cascade . | Matching Sentences: [ Sen. 5, subscore: 1.00 ]: When a dominant MST7 allele with S212D and T216E mutations was introduced into the mst7 or mst11 mutant , appressorium formation was restored in the resulting transformants . [ Sen. 6, subscore: 1.00 ]: PMK1 phosphorylation also was detected in the vegetative hyphae and appressoria of transformants expressing the MST7 ( S212D T216E ) allele . [ Sen. 8, subscore: 1.00 ]: The intracellular cAMP level was reduced in transformants expressing the MST7 ( S212D T216E ) allele .
| Supplemental links/files: reference in endnote online text related articles pubmed citation | |