Plant Growth Based on Interrelation between Carbon and Nitrogen Translocation from Leaves

Five strains of Streptomyces (CAI-17, CAI-68, CAI-78, KAI-26, and KAI-27) were previously reported to have potential for charcoal rot control and plant growth promotion (PGP) in sorghum. In this study, those 5 Streptomyces strains were characterized for their enzymatic activities and evaluated for their PGP capabilities on rice. All the Streptomyces strains were able to produce lipase and β-1,3-glucanase; grew in NaCl (up to 8%), at pH 5–13, and at temperatures 20–40 °C; and were resistant to ampicillin, sensitive to nalidixic acid, and highly sensitive to chloramphenicol, kanamycin, streptomycin, and tetracycline. They were highly tolerant to the fungicide bavistin but were highly sensitive to benlate, benomyl, and radonil. When evaluated on rice in the field, Streptomyces significantly enhanced tiller and panicle numbers, stover and grain yields, dry matter, root length, volume and dry weight, compared with the control. In the rhizosphere at harvest, microbial biomass carbon and nitrogen, dehydrogenase activity, total nitrogen, available phosphorus, and % organic carbon were also found significantly higher in Streptomyces-treated plots than in the control plots. This study further confirms that the selected Streptomyces have PGP activities.

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Production of Plant Growth Regulators by Some Fungi Isolated under Salt Stress

South Asian Journal of Research in Microbiology ◽

10.9734/sajrm/2019/v3i130076 ◽

2019 ◽

pp. 1-10

Author(s):

Samah N. El-Dien Solyman ◽

Mohamed O. Abdel-Monem ◽

Khadiga A. Abou-Taleb ◽

Hany S. Osman ◽

Reyad M. El-Sharkawy

Keyword(s):

Plant Growth ◽

Plant Growth Regulators ◽

Growth Regulators ◽

Indole Acetic Acid ◽

Solid Medium ◽

Basal Medium ◽

Nitrogen Sources ◽

Growth Zone ◽

Carbon And Nitrogen ◽

Produce Plant

Fifty-eight fungal isolates were isolated from salt soil, whey and salt fish on medium supplemented with 0.5% NaCl. Out of 58 isolates, 49 were capable to grow on medium supplemented with 1 % NaCl. These halo-tolerant isolates were tested to produce plant growth regulators (PGR) on solid or in broth medium. On solid medium, 9 halo-tolerant isolates out of 58 isolates were gave indole acetic acid (IAA) which appeared red zone around growth zone with index ranged from 0.25 to 0.56. While in broth medium, 9 isolates were tried to produce IAA and gibberellic acid (GA) in presence of NaCl at 0.5 or 1%. The maximum IAA and GA production were obtained by FS12 isolate (4.32 and 4.52 mg/100ml) and by FW2 isolate (2.71 and 2.92 mg/100ml) at 0.5% and 1% NaCl, respectively. FS12 was selected as the most efficient isolate for plant growth regulators (PGR) production and identified as Aspergillus niger. Carbon and nitrogen sources were studiedfor PGR optimization by the tested strain. Whey and peptone were used as a sole carbon and nitrogen source, where increased the IAA and GA production about 15.4% and 71.3% as compared to control (basal medium).

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Carbon and nitrogen reserves in marandu palisade grass subjected to intensities of continuous stocking management

The Journal of Agricultural Science ◽

10.1017/s0021859614001130 ◽

2014 ◽

Vol 153 (8) ◽

pp. 1449-1463 ◽

Cited By ~ 13

Author(s):

S. C. DA SILVA ◽

L. E. T. PEREIRA ◽

A. F. SBRISSIA ◽

A. HERNANDEZ-GARAY

Keyword(s):

Plant Growth ◽

Leaf Area ◽

Grazing Intensity ◽

Late Spring ◽

Area Index ◽

Total N ◽

Carbon And Nitrogen ◽

Grazing Intensities ◽

C And N ◽

Four Levels

SUMMARYPlant organic reserves and sward leaf area index (LAI) influence plant growth, persistency and herbage accumulation in grazed swards. The present study was conducted to describe patterns of variation in herbage accumulation and carbohydrate and nitrogen (N) reserves in shoot and root of marandu palisade grass subjected to intensities of continuous stocking management throughout the year. Treatments corresponded to four levels of grazing intensity – severe (S), severe/moderate (S/M), moderate (M) and lenient (L) – and were implemented in the field using bands of sward surface height (SSH – 10, 20, 30 and 40 cm ± 10%, respectively) maintained through continuous stocking and variable stocking rate. Total N concentration was higher in the shoot relative to the root compartment during autumn, early and late spring. On the other hand, the concentration of non-structural carbohydrates (NSC) and soluble N was higher in the root compartment, regardless of grazing intensity and season of the year. When taking into account the pool of C and N reserves, the shoot compartment represented the main storage organ, since it corresponded to the largest pool of NSC (averages of 0·102 ± 0·0038 and 0·201 ± 0·0088 kg/m2 for root and shoot, respectively) and soluble N (averages of 2·7 ± 0·26 and 5·3 ± 0·59 kg/m2 for root and shoot, respectively). During late spring, the time of active plant growth, there was a clear contrast in herbage accumulation and sward LAI among grazing intensities, particularly between the severe and lenient grazing treatments. The results show that even with larger pools of soluble N and NSC in the shoot compartment, herbage accumulation was limited by the reduced leaf area of swards subjected to the severe grazing treatment, indicating that under continuous stocking growth seems to be sustained by current assimilates instead of organic reserves. Therefore, targets of grazing management for maximizing herbage accumulation throughout the year should provide adequate combinations between quantity and quality of sward leaf area. This condition was obtained in the severe/moderate and moderate grazing intensities, and corresponded to sward heights between 20 and 30 cm for marandu palisade grass.

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