15 výsledky
Corn (Zea mays L.) plants were assayed for nitrogenase activity (C(2)H(2) reduction) during early ear development. Hybrid corn and inbred lines were grown separately at two experimental fields in New Jersey. Acetylene-dependent ethylene production was observed a few hours after harvest, from the
Endogenous ethylene production was evaluated as a source of ethylene during acetylene reduction assays with freshly collected roots of field-grown corn, Zea mays L. cv Funks G-4646, and sorghum, Sorghum bicolor (L.) Moench. cv CK-60A. Ethylene production was not detected when roots were incubated in
Maize roots can be colonized by free-living atmospheric nitrogen (N2)-fixing bacteria (diazotrophs). However, the agronomic potential of non-symbiotic N2-fixation in such an economically important species as maize, has still not been fully exploited. A preliminary approach to improve our
The presence and diversity of the endophytic Arthrobacter species are relatively uninvestigated. We determined the genotypic and physiological diversity of the endophytic Arthrobacter spp. isolated from the interior leaf tissues of four out of six maize cultivars tested, all of which were collected
The endophytic lifestyle of Klebsiella pneumoniae is described, including the production of dinitrogenase reductase by bacteria residing in maize root tissue. The green fluorescent protein (GFP) was used to detect the colonization of maize by K. pneumoniae strains 2028 and 342. These strains were
World climate change has triggered soil water stress and imposed limitations on agricultural production. Plant growth-promoting bacteria (PGPBs) have been an efficient strategy to improve the biological supply and growth of plants under distinct abiotic stress conditions. We hypothesized that the
Nitrogen fixation by bacteria associated with roots of intact maize plants was measured by exposing the roots to N(2) at a partial O(2) pressure (pO(2)) of 2 or 10 kPa. The plants were grown in a mixture of Weswood soil and sand and then transferred to plastic cylinders containing an N-free plant
OBJECTIVE
This study was undertaken to investigate whether a nitrogen-fixing bacterium Enterobacter gergoviae 57-7, which was isolated from surface-sterilized maize (Zea mays L.) roots, can colonize in roots and whether constitutive expression of the nifA gene encoding the transcriptional activator
Numbers and possible locations of N(2)-fixing bacteria were investigated in roots of Spartina alterniflora Loisel, which support nitrogenase activity in the undisturbed native habitat. N(2)-fixing bacteria were recovered in cultures both from S. alterniflora roots and from the surrounding sediment,
N(2) fixation in field-grown maize (Zea mays L.) plants was estimated by a nondestructive acetylene reduction method which permitted the plants to continue growing and produce seeds. Samples from six areas revealed mean nitrogenase activities of 74-2167 nmol of C(2)H(4)/(g of dry roots x hr) for 10
Nitrogenase activity was measured by the C(2)H(2) reduction method in large soil cores (29 cm in diameter by 20 cm in depth) of maize (Zea mays) and sorghum (Sorghum vulgare). The activity was compared to that obtained by a method in which the roots were removed from the soil and assayed for
A number of nitrogen fixing bacteria has been isolated from forest phyllosphere on the basis of nitrogenase activity. Among them two best isolates are selected and identified as Corynebacterium sp. AN1 & Flavobacterium sp. TK2 able to reduce 88 and 132 n mol of acetylene (10(8)cells(-1)h(-1))
Examination of root systems and adhering soil associated with unusually green corn plants from nitrogen-deficient areas in fields has revealed higher acetylene-reducing activities than comparable root systems of chlorotic plants that appeared to be nitrogen deficient. From the root systems with
Kosakonia radicincitans GXGL-4A, a free-living nitrogen-fixing (NF) bacterial strain isolated from maize (Zea mays L.) roots was found to have ability to degrade aromatic hydrocarbons. In this study, we describe the main morphological characteristics of bacterium, aromatic hydrocarbon-degrading
Corn has shown different degrees of positive response to inoculation with the nitrogen- fixing bacteria of the genera Azospirillum. Part of it has been attributed to the plant genotypic variation, including the root exudates, that are used by the bacteria as energy source. In this study, we