We study the "hidden" half of plants, the roots and the myriad microbes that associate with the underground part of the plant. Our research also encompasses plant microbiomes, particularly the legume nodule microbiome where nitrogen-fixing and “other” bacteria reside. Our focus is on beneficial bacteria and the mechanisms whereby they help plants grow, develop, fight disease, and prosper. We want to develop consortia of bacteria that can replace chemical fertilizers, insecticides, and fungicides towards for not only achieving sustainable agriculture, but also for restoring soil health.
Current plant science and biotechnology in agriculture, 1987
The ability of critical symbiotic functions to be provided to one bacterium by another (i.e., in ... more The ability of critical symbiotic functions to be provided to one bacterium by another (i.e., in trans) during the course of nodule development has been examined with derivatives of the alfalfa symbiont R. meliloti SU47.
The involvement of root hairs in the establishment of the Rhizobium-legume symbiosis is well know... more The involvement of root hairs in the establishment of the Rhizobium-legume symbiosis is well known although the root hair is by no means the only point of entry of the bacteria into the plant root. A number of legumes are invaded by the so-called “crack entry” mode of penetration (Sprent 1989) whereby rhizobia enter the root either between epidermal cells or through breaks made through the root cortex by elongating lateral roots. In root hair entry, rhizobia dock on the root hairs, which deform in response to secreted Nod factors, and then the rhizobia enter the curled root hair by means of an infection thread (see Chapter 15 this volume).
Advances in Experimental Medicine and Biology, 2002
1. BACKGROUND More than 4,000 different flavonoids, which are widely distributed in higher plants... more 1. BACKGROUND More than 4,000 different flavonoids, which are widely distributed in higher plants, have been identified (Harbome, 1988; Koes et al. 1994). Flavonoids are involved in numerous functions in vascular plants. One obvious function is as a filter for ...
Summary of known biofilm-forming rhizosphere bacteria Organism Phenotype Relevant Characteristics ... more Summary of known biofilm-forming rhizosphere bacteria Organism Phenotype Relevant Characteristics Reference Acinetobacter calcoaceticus P23 Root colonization of duckweed PGPB, bioremediation Yamaga et al. (2010) Agrobacterium tumefaciens Disease of pea Pathogenesis Hawes and Smith (1989) Azorhizobium brasilense Root colonization of wheat PGPR Kim et al. (2005) Azorhizobium caulinodans Root colonization of rice PGPR Van Nieuwenhove et al. (2000) Bacillus amyloliquefaciens S499Root colonization of tomato,maize, and Arabidopsisthaliana PGPB, biocontrol Nihorimbere et al. (2012);Fan et al. (2011) Bacillus cereus and Bacilluspumilus Root colonization of wildbarley found in theEvolution Canyon, IsraelSalt, heat, and desiccationtoleranceTimmusk et al. (2011) Bacillus polymyxa Root colonization of cucumber PGPB Yang et al. (2004) Bacillus subtilis Root colonization of Arabidopsis thaliana Biocontrol Rudrappa and Bais (2007) Burkholderia cepacia and Burkholderia cenocepacia Diseases of onion and wheat Pathogenesis Ellis and Cooper (2010);Jacobs et al. (2008);Balandreau et al. (2001)
Current plant science and biotechnology in agriculture, 1987
The ability of critical symbiotic functions to be provided to one bacterium by another (i.e., in ... more The ability of critical symbiotic functions to be provided to one bacterium by another (i.e., in trans) during the course of nodule development has been examined with derivatives of the alfalfa symbiont R. meliloti SU47.
The involvement of root hairs in the establishment of the Rhizobium-legume symbiosis is well know... more The involvement of root hairs in the establishment of the Rhizobium-legume symbiosis is well known although the root hair is by no means the only point of entry of the bacteria into the plant root. A number of legumes are invaded by the so-called “crack entry” mode of penetration (Sprent 1989) whereby rhizobia enter the root either between epidermal cells or through breaks made through the root cortex by elongating lateral roots. In root hair entry, rhizobia dock on the root hairs, which deform in response to secreted Nod factors, and then the rhizobia enter the curled root hair by means of an infection thread (see Chapter 15 this volume).
Advances in Experimental Medicine and Biology, 2002
1. BACKGROUND More than 4,000 different flavonoids, which are widely distributed in higher plants... more 1. BACKGROUND More than 4,000 different flavonoids, which are widely distributed in higher plants, have been identified (Harbome, 1988; Koes et al. 1994). Flavonoids are involved in numerous functions in vascular plants. One obvious function is as a filter for ...
Summary of known biofilm-forming rhizosphere bacteria Organism Phenotype Relevant Characteristics ... more Summary of known biofilm-forming rhizosphere bacteria Organism Phenotype Relevant Characteristics Reference Acinetobacter calcoaceticus P23 Root colonization of duckweed PGPB, bioremediation Yamaga et al. (2010) Agrobacterium tumefaciens Disease of pea Pathogenesis Hawes and Smith (1989) Azorhizobium brasilense Root colonization of wheat PGPR Kim et al. (2005) Azorhizobium caulinodans Root colonization of rice PGPR Van Nieuwenhove et al. (2000) Bacillus amyloliquefaciens S499Root colonization of tomato,maize, and Arabidopsisthaliana PGPB, biocontrol Nihorimbere et al. (2012);Fan et al. (2011) Bacillus cereus and Bacilluspumilus Root colonization of wildbarley found in theEvolution Canyon, IsraelSalt, heat, and desiccationtoleranceTimmusk et al. (2011) Bacillus polymyxa Root colonization of cucumber PGPB Yang et al. (2004) Bacillus subtilis Root colonization of Arabidopsis thaliana Biocontrol Rudrappa and Bais (2007) Burkholderia cepacia and Burkholderia cenocepacia Diseases of onion and wheat Pathogenesis Ellis and Cooper (2010);Jacobs et al. (2008);Balandreau et al. (2001)
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