<i>Rhizobium</i>-stimulated Callose Formation in Clover Root Hairs and its Relation to Infection

Kumarasinghe, Rohini M. K.; Nutman, P. S.

doi:10.1093/jxb/28.4.961

Cited by 27 publications

(14 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As shown by Kumarasinghe and Nutman (1977), the presence of Rhizobium trifolii stimulated synthesis of callose in Trifolium plants, at the sites of infection-thread initiation. No other deposits were observed in the infection process.…”

Section: Discussionmentioning

confidence: 91%

“…In the Alnus rubra-Frankia symbiosis, callose deposits were only observed in the case of arrested infections (Berry and McCully 1990). Interestingly, Sethi and Reporter (1981) found an increase of free calcium in the areas corresponding to those where Kumarasinghe and Nutman (1977) observed callose. Calcium activates the [3(1,3)-glucan synthase activity by directly affecting the enzyme (Kauss 1987).…”

Section: Discussionmentioning

confidence: 98%

See 1 more Smart Citation

Plant defence and delayed infection of alfalfa pseudonodules induced by an exopolysaccharide (EPS I)-deficient Rhizobium meliloti mutant

Niehaus

Kapp

Pühler³

1993

Planta

193

View full text Add to dashboard Cite

Abstract.Mutants of the symbiotic soil bacterium Rhizobium melitoti that fail to synthesize the acidic exopolysaccharide EPS I were unable to induce infected root nodules on Medicago sativa L. (alfalfa). These strains, however, elicited pseudonodules that contained no infection threads or bacteroids. The cortical cell walls of the pseudonodules were abnormally thick and incrusted with an autofluorescent material. Parts of these cell walls and wall appositions contained callose. Biochemical analysis of nodules induced by the EPS I-deficient R. meIiloti mutant revealed an increase of phenolic compounds bound to the nodule cell walls when compared with the wildtype strain. These microscopic and biochemical data indicated that a general plant defence response against the EPS I-deficient mutant of R. meliloti was induced in alfalfa pseudonodules. Following prolonged incubation with the EPS I-deficient R. meliloti mutant, the defence system of the alfalfa plant could be overcome by the rhizobium mutant. In the case of the delayed infections, the mutants colonized lobes of the pseudonodules, but the infection threads in these nodules had an abnormal morphology. They were greatly enlarged and did not contain the typical gum-like matrix inside. The bacteria were tightly packed. Based on the mechanism of phytopathogenic interactions, we propose that EPS I or a related compound may act as a suppressor of the alfalfa plant defence system, enabling R. meliloti to infect the plant.

show abstract

Section: Discussionmentioning

confidence: 91%

Section: Discussionmentioning

confidence: 98%

Plant defence and delayed infection of alfalfa pseudonodules induced by an exopolysaccharide (EPS I)-deficient Rhizobium meliloti mutant

Niehaus

Kapp

Pühler³

1993

Planta

193

View full text Add to dashboard Cite

show abstract

“…Quantitative light microscopic assays (Dazzo et al, 1976;Dazzo, 1980a) and transmission electron microscopic studies Kumarasinghe & Nutman, 1977;Dazzo, 1980 c) of the Rhizobium-clover symbiosis have revealed multiple mechanisms of bacterial attachment to the root hairs. A nonspecific mechanism allows all species of rhizobia to attach in low numbers (2-4 cells per 200 I-tm root hair length per 12 hr using low inoculum per seedling).…”

Section: Bacterial Attachment Is An Early Recognition Step Of Root-hamentioning

confidence: 99%

Interactions of lectins and their saccharide receptors in theRhizobium-legume symbiosis

Dazzo

Truchet

1983

J. Membrain Biol.

View full text Add to dashboard Cite

“…Kumarasinghe and Nutman (1977) reported that the root hairs treated with Rhizobia revealed thickening of the walls which was sometimes associated with arrays of vesicles of neighboring cytoplasm. The nodulation process in rhizobia-legume symbiosis requires a sequence of highly regulated and coordinated events, initiated by an exchange of specific signaling compounds between both partners.…”

Section: Change In Root Growth and Morphologymentioning

confidence: 99%

Arbuscular Mycorrhizal Fungi and Rhizobium to Control Plant Fungal Diseases

Akhtar

Siddiqui

Wiemken

2010

Alternative Farming Systems, Biotechnology, Drought Stress and Ecological Fertilisation

View full text Add to dashboard Cite

Soil microorganisms can be used to decrease the input of fertilizers, pesticides and other chemicals. Among soil microorganisms, arbuscular mycorrhizal (AM) fungi and Rhizobium spp. can promote plant growth and control plant fungal diseases. However these microorganisms are not yet used in commercial biocontrol products. Integration of arbuscular mycorrhizal fungus with Rhizobium sp. thus appears to be a promising approach for sustainable agriculture. Arbuscular mycorrhizal fungi and root-nodule bacterium Rhizobium are two root symbionts. Arbuscular mycorrhizal fungi increases soil nutrients and water absorption, while root-nodule bacteria fix atmospheric nitrogen and produce antibiotics and phytoalexins. These microbes modify the quality and abundance of rhizosphere microflora and alter overall microbial activity of the rhizosphere. They induce changes in the host root exudation pattern. A procedure for successful development of these microorganisms is required by selection and screening of efficient isolates. Knowledge of culture systems that are adapted to their establishment and multiplication is needed. Arbuscular mycorrhizal fungi provide specific niches for bacteria. Arbuscular mycorrhizal bacteria improve nutrient acquisition in plants. Arbuscular mycorrhizal bacteria may contribute to ability of arbuscular mycorrhizal fungi to inhibit pathogens, acquire mineral nutrients and modify plant root growth. Combined use of these microorganisms is more beneficial than their use alone. These symbionts also interact with other beneficial microorganisms synergistically and can be exploited for sustainable agriculture.

show abstract

Rhizobium-stimulated Callose Formation in Clover Root Hairs and its Relation to Infection

Cited by 27 publications

References 1 publication

Plant defence and delayed infection of alfalfa pseudonodules induced by an exopolysaccharide (EPS I)-deficient Rhizobium meliloti mutant

Plant defence and delayed infection of alfalfa pseudonodules induced by an exopolysaccharide (EPS I)-deficient Rhizobium meliloti mutant

Interactions of lectins and their saccharide receptors in theRhizobium-legume symbiosis

Arbuscular Mycorrhizal Fungi and Rhizobium to Control Plant Fungal Diseases

Contact Info

Product

Resources

About