Electron microscopic study of associative n<sub>2</sub>-fixing bacteria in roots of rice seedlings

Nishizawa, Naoko K.; Yoshida, Tomio; Arima, Yasushi

doi:10.1080/00380768.1983.10434627

Cited by 7 publications

(3 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The rice rhizosphere is abundantly supplied with organic matter from rice roots in the form of exudates containing sugars, amino acids, organic acids (Kimura et al 1977), and mucigel (Nishizawa et al 1983;Kimura et al 1989). High microbial activities were also detected for the production of CO2, CH4, and H2 in the rice rhizosphere (Kimura et al 1984).…”

mentioning

confidence: 99%

CO₂, H₂, and CH₄production in rice rhizosphere

Kimura

Murakami

Wada

1991

Soil Science and Plant Nutrition

View full text Add to dashboard Cite

mentioning

confidence: 99%

CO₂, H₂, and CH₄production in rice rhizosphere

Kimura

Murakami

Wada

1991

Soil Science and Plant Nutrition

View full text Add to dashboard Cite

“…Several workers have reported bacteria invading the intercellular spaces of root nodules of rice, despite their absence in cells (Nishizawa et al 1983;Christiansen-Waniger 1996). It is quite conceivable that young coleoptiles are very resistant to various environmental in¯uences and that senescence removes this resistance, allowing microorganisms to invade the coleoptiles.…”

Section: Discussionmentioning

confidence: 99%

Three-dimensional analysis of the senescence program in rice ( Oryza sativa L.) coleoptiles

Inada

Sakai

Kuroiwa

et al. 1998

Planta

View full text Add to dashboard Cite

The cytological sequence of senescence-related changes in coleoptiles of rice (Oryza sativa L. cv. Nippon-bare) was studied using¯uorescence and electron microscopy. The coleoptiles reach full size 3 d after sowing, then rapidly senesce and wither completely by day 7. The interveinal region in cross-sections taken 1 mm from the tip of the coleoptile was selected for this analysis. Fluorescence microscopy using samples embedded in Technovit 7100 resin, electron microscopy and immunoelectron microscopy using DNA-speci®c antibodies were used to elucidate the sequence of senescence-related events. These occur in the following order: (i) degradation of the chloroplast DNA (cpDNA); (ii) condensation of the nucleus in conjunction with a decrease in the size of the dense-chromatin region, shrinkage of the chloroplast, degradation of ribulose-1, 5-bisphosphate carboxylase/oxygenase, dilation of the thylakoid membranes, increase in size and number of osmiophilic globules, condensation of the cytoplasm; (iii) disorganization of the nucleus, degeneration of the tonoplast; (iv) complete loss of the cytoplasmic components, distortion of the cell wall, invasion of microorganisms into the intercellular spaces and ultimately into the cell itself. The mitochondria maintain their ultrastructural integrity and a constant level of mitochondrial DNA throughout senescence. In young mesophyll cells, invagination of the tonoplast into the vacuole frequently occurs. This occasionally includes cytoplasmic material, which is digested in the vacuole as senescence proceeds. Immunoelectron microscopy suggests that cpDNA degradation involves rough digestion ®rst, rather than rapid, direct decomposition of the DNA into nucleotides. The fragmented cpDNA is then dispersed throughout the chloroplast and cytoplasm.

show abstract

“…The slimy material may serve as food for bacteria and is, ac~ording to Nishizawa et al (1983), of particular importance for the N 2-flXing bacteria. Guckert et al (1975) showed by means of an electron micrograph that the bacteria are embedded in the slime and may dissolve it by lytic enzymes.…”

mentioning

confidence: 99%

Advances in Soil Science

1985

Advances in Soil Science

View full text Add to dashboard Cite

Electron microscopic study of associative n₂-fixing bacteria in roots of rice seedlings

Cited by 7 publications

References 15 publications

CO₂, H₂, and CH₄production in rice rhizosphere

CO₂, H₂, and CH₄production in rice rhizosphere

Three-dimensional analysis of the senescence program in rice ( Oryza sativa L.) coleoptiles

Advances in Soil Science

Contact Info

Product

Resources

About

Electron microscopic study of associative n2-fixing bacteria in roots of rice seedlings

Cited by 7 publications

References 15 publications

CO2, H2, and CH4production in rice rhizosphere

CO2, H2, and CH4production in rice rhizosphere

Three-dimensional analysis of the senescence program in rice ( Oryza sativa L.) coleoptiles

Advances in Soil Science

Contact Info

Product

Resources

About

Electron microscopic study of associative n₂-fixing bacteria in roots of rice seedlings

CO₂, H₂, and CH₄production in rice rhizosphere

CO₂, H₂, and CH₄production in rice rhizosphere