Varying the ratio of15N-labelled ammonium and nitrate-N supplied to creeping bent: effects on nitrogen absorption and assimilation, and plant growth

One component of container production influencing the water quality concerns in the nursery industry is the amount of container effluent leaching from the container substrate. Potential exists for reduced water use, less leachate volume, and improved irrigation efficiency by altering the container design. This research compares the container leachate volume from a standard, 11.31 (# 3) container with seven 1.9-cm-diameter drainage holes to containers with one, three, or five holes with diameters of 1.9, 0.9, and 0.5 cm. Leachate volume was 41% less (312 to 182 mL) when the diameter of the drainage hole was reduced from 1.9 to 0.5 cm. Nitrate-N was 85% less (3093 to 452 mg) when the container drainage holes were reduced to 0.5 cm. Plant growth and quality of Lagerstroemia fauriei X L. indica `Hopi', crapemyrtle, was similar in all container modifications.

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Effects of Different NH4:NO3 Ratios on Growth and Nutrition Uptake in Iris germanica ‘Immortality’

HortScience ◽

10.21273/hortsci.51.8.1045 ◽

2016 ◽

Vol 51 (8) ◽

pp. 1045-1049 ◽

Cited By ~ 4

Author(s):

Xiaojie Zhao ◽

Guihong Bi ◽

Richard L. Harkess ◽

Eugene K. Blythe

Keyword(s):

Plant Growth ◽

Dry Weight ◽

Growing Season ◽

Physiological Processes ◽

Nitrate N ◽

Growth And Nutrition ◽

Iris Germanica ◽

Net Uptake ◽

Total Plant ◽

N Form

The form of nitrogen (N) in fertilizer can influence plant growth, nutrient uptake, and physiological processes in the plant. However, few studies have been conducted on the effects of N form on tall bearded (TB) iris (Iris germanica L.). In this study, five NH4:NO3 ratios (0:100, 25:75, 50:50, 75:25, and 100:0) were applied to investigate the response of TB iris to different N form ratios. NH4:NO3 ratios in fertilizer did not affect the leaf, root, and rhizome dry weight, or total plant dry weight. Plant height and SPAD reading were affected by NH4:NO3 ratios in some months, but not over the whole growing season. Neither spring nor fall flowering was influenced by NH4:NO3 ratios. Across the whole growing season, leachate pH was increased by higher NH4:NO3 ratios. At the end of the growing season, concentrations of phosphorous (P), iron (Fe), manganese (Mn), zinc (Zn), copper (Cu) in leaf; calcium (Ca), magnesium (Mg), Mn, boron (B) in root; and N, P, Mg, Fe, Mn, and Zn in rhizome tissues were affected by NH4:NO3 ratios. Greater NH4:NO3 ratios increased the uptake of Fe, Mn, and Zn. The net uptake of N was unaffected by NH4:NO3 ratios, which indicates TB iris may not have a preference for either ammonium or nitrate N.

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Mechanisms of ethylene biosynthesis and response in plants

Essays in Biochemistry ◽

10.1042/bse0580061 ◽

2015 ◽

Vol 58 ◽

pp. 61-70 ◽

Cited By ~ 11

Author(s):

Paul B. Larsen

Keyword(s):

Plant Growth ◽

Growth And Development ◽

Ethylene Biosynthesis ◽

Unsaturated Hydrocarbon ◽

Flower Senescence ◽

Detailed Knowledge ◽

Plant Growth And Development ◽

Step Process ◽

Ethylene Response ◽

Ethylene Signalling

Ethylene is the simplest unsaturated hydrocarbon, yet it has profound effects on plant growth and development, including many agriculturally important phenomena. Analysis of the mechanisms underlying ethylene biosynthesis and signalling have resulted in the elucidation of multistep mechanisms which at first glance appear simple, but in fact represent several levels of control to tightly regulate the level of production and response. Ethylene biosynthesis represents a two-step process that is regulated at both the transcriptional and post-translational levels, thus enabling plants to control the amount of ethylene produced with regard to promotion of responses such as climacteric flower senescence and fruit ripening. Ethylene production subsequently results in activation of the ethylene response, as ethylene accumulation will trigger the ethylene signalling pathway to activate ethylene-dependent transcription for promotion of the response and for resetting the pathway. A more detailed knowledge of the mechanisms underlying biosynthesis and the ethylene response will ultimately enable new approaches to be developed for control of the initiation and progression of ethylene-dependent developmental processes, many of which are of horticultural significance.

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