Littérature scientifique sur le sujet « Rhizobiaceae Biological control »

ABSTRACT The family Rhizobiaceae contains plant-associated bacteria with critical roles in ecology and agriculture. Within this family, many Rhizobium and Sinorhizobium strains are nitrogen-fixing plant mutualists, while many strains designated as Agrobacterium are plant pathogens. These contrasting lifestyles are primarily dependent on the transmissible plasmids each strain harbors. Members of the Rhizobiaceae also have diverse genome architectures that include single chromosomes, multiple chromosomes, and plasmids of various sizes. Agrobacterium strains have been divided into three biovars, based on physiological and biochemical properties. The genome of a biovar I strain, A. tumefaciens C58, has been previously sequenced. In this study, the genomes of the biovar II strain A. radiobacter K84, a commercially available biological control strain that inhibits certain pathogenic agrobacteria, and the biovar III strain A. vitis S4, a narrow-host-range strain that infects grapes and invokes a hypersensitive response on nonhost plants, were fully sequenced and annotated. Comparison with other sequenced members of the Alphaproteobacteria provides new data on the evolution of multipartite bacterial genomes. Primary chromosomes show extensive conservation of both gene content and order. In contrast, secondary chromosomes share smaller percentages of genes, and conserved gene order is restricted to short blocks. We propose that secondary chromosomes originated from an ancestral plasmid to which genes have been transferred from a progenitor primary chromosome. Similar patterns are observed in select Beta- and Gammaproteobacteria species. Together, these results define the evolution of chromosome architecture and gene content among the Rhizobiaceae and support a generalized mechanism for second-chromosome formation among bacteria.

Introduction. The results of research on the effect of different rates of Panda herbicide, Stimpo growth regulator and Rizobofit microbial preparation on leaf surface area formation and chickpea cultivar Pamyat' yields are presented. As a result of the conducted research, the most effective combination of preparations, which provides a significant increase of photosynthetic surface of leaves and as a result grain productivity of chickpea crops, was established. Purpose. To study the effect of different rates of Panda herbicide applied separately or in the background of plant treatment with biologic preparations - plant growth regulator Stimpo and 32 Серія «Біологічні науки», 202 2microbial preparation Rizobofit - on the formation of leaf area and grain productivity of chickpea cultivar Pamyat.Methods. The study plan included variations with the use of Panda herbicide at the rates of 3.0; 4.0; 5.0; 6.0 l / ha (active substance - pendimethaline) separately and on the background of the plant growth regulator (PPP) Stimpo at a rate of 0.025 l / t (biologically active substances complex), microbial preparation (MBP) Rizobofit at the rate of 1.0 l/t (bacteria of Rhizobiacea genus ST 282 ) and the combination of growth regulator Stimpo and microbial preparation Rizobofit at the same rates for chickpea cultivar Pamyat'.Measurement and examination of the density of leaves and grain yield were carried out according to the methods described by Z. M. Gritsiyenko and his co-workers. Statistical processing of the research results was carried out according to the methods of dispersion analysis, presented by B.A. Dospekhovy.Results. Chickpea leaf area formation is highly dependent on weather conditions and norms of herbicide application separately and on the background of biological preparations. The largest area of chickpea leaves in the study is formed in variants of complex use of preparations, particularly herbicide Panda at a rate of 4.0 l / ha with a growth regulator Stimpo (0, 025 l / t) and microbiological preparation Rizobofit (1.0 l / t), in this case during the phases of growth the leaf area exceeded control I on average by 66-84%. Some decrease in the density of leaf apparatus is due to the applying of herbicide at rates of 5.0 and 6.0 l / ha, that can be attributed to the main physiological and biochemical processes inhibition in plants due to high xenobiotic standards. The highest yield indicators and chickpea grain quality are formed when Panda herbicide at the rate of 4, 0 l / ha on the background of the treatment of crops before planting RRR Stimpo (0.025 l / t) and IBP Rizobofit (1.0 l / t) are applied, in which case for this combination of preparations Crop Yield increases by 0.64 t / ha.Originality. The main goal is to demonstrate physiological, biochemical, microbiological and production changes in chickpea plants and planting soil at different rates of herbicide and biologic preparations. Conclusions. With the purpose of biological processes activation and chickpea crops productivity increase under the conditions of the Right-bank Forest-steppe of Ukraine, it is advisable to treat chickpea seeds before sowing a mixture of microbial preparations based on symbiotic bacteria Mesorhizobium siceri with a titer of living cells not less than 4, 0·109 CU/ml (Rizobofit, p. ; Rizoaktiv Beans Brand R analogue) at the rate of 1.0 l/t, growth regulator Stimpo, WP at the rate of 0.025 l/t and apply Panda herbicide at the rate of 4.0 l/ha against storms on the above mentioned background.Key words: chickpea; leaf surface area; herbicide; growth regulator; microbial preparation.

Thesis (Ph. D.)--University of Adelaide, Dept. of Crop Protection and Plant Science, 1996.
Copies of author's previously published articles inserted. Includes bibliographical references (leaves 72-90).

Copy of author's previously published work inserted. Bibliography: leaves 114-136. The study concentrates on: investigation of the biological properties and role of agrocin 434 and other factors in the bicontrol process of crown gall disease; isolation of the complete range of K84 derivatives carrying different combinations of plasmids pAgK84, pAgK434 and pAtK84b in the same host background; development of a rapid plant bioassay to assess the efficacy of biocontrol strains by leaf disc tumorigenesis assay; and characterization of agrocin 434 synthesis and immunity genes.

Copy of author's previously published work inserted.
Bibliography: leaves 114-136.
xiv, 144, [19] leaves, [18] leaves of plates : ill. (some col.) ; 30 cm.
The study concentrates on: investigation of the biological properties and role of agrocin 434 and other factors in the bicontrol process of crown gall disease; isolation of the complete range of K84 derivatives carrying different combinations of plasmids pAgK84, pAgK434 and pAtK84b in the same host background; development of a rapid plant bioassay to assess the efficacy of biocontrol strains by leaf disc tumorigenesis assay; and characterization of agrocin 434 synthesis and immunity genes.
Thesis (Ph.D.)--University of Adelaide, Dept. of Crop Protection, 1997

Copies of author's previously published articles inserted.
Bibliography: leaves 72-90.
vii, 101, [28] leaves, [12] leaves of plates : ill. ; 30 cm.
Crown gall is a plant cancer caused by pathogenic strains of Agrobacterium, a soil microorganism belonging to the family Rhizobiaceae. This thesis examines the possible role in the biological control process, of an antibiotic compound agrocin 434, produced by biocontrol strains, in addition to the well-characterized adenine nucleotide, agrocin 84.
Thesis (Ph.D.)--University of Adelaide, Depts. of Crop Protection and Plant Science, 1996

Includes two journal articles with contributions by the author
Bibliography: leaves 145-154
vii, 164 leaves : ill ; 30 cm.
Thesis (Ph.D.)--University of Adelaide, Dept. of Plant Pathology, 1988