<abstract xmlns="http://www.w3.org/1999/xhtml"><p>The objective of this study was to quantify the proteolytic activity of a set of 10 diploid early intermediate heading cultivars of <italic>Lolium perenne</italic> under rumenlike conditions. A field experiment was conducted in Northern Germany, where the perennial ryegrass cultivars were grown during two growing seasons. Leaves of the first and second cut were sampled in the field, sterilized with 800 ml. l<sup>−1</sup> ethanol solution and incubated for 0, 6, and 24 h under rumenlike conditions (darkness, 39°C, pH 6.5) without the presence of rumen microbes. Results revealed that the leaf protein content declined with increasing incubation time, confirming the involvement of plant-mediated proteolysis in the degradation process. Gel electrophoresis illustrated that the decrease in protein content is probably mainly caused by the loss of the large subunit of Rubisco (ribulose-1, 5-bisphosphate carboxylase/oxygenase), which was entirely degraded during the incubation time. Although differences among harvests and years were evident, genetic variation among the 10 diploid perennial grass samples concerning protein degradation rates and degradation characteristics was not detected.</p></abstract>

The objective of this study was to quantify the proteolytic activity of a set of 10 diploid early intermediate heading cultivars of Lolium perenne under rumenlike conditions. A field experiment was conducted in Northern Germany, where the perennial ryegrass cultivars were grown during two growing seasons. Leaves of the first and second cut were sampled in the field, sterilized with 800 ml. l−1 ethanol solution and incubated for 0, 6, and 24 h under rumenlike conditions (darkness, 39°C, pH 6.5) without the presence of rumen microbes. Results revealed that the leaf protein content declined with increasing incubation time, confirming the involvement of plant-mediated proteolysis in the degradation process. Gel electrophoresis illustrated that the decrease in protein content is probably mainly caused by the loss of the large subunit of Rubisco (ribulose-1, 5-bisphosphate carboxylase/oxygenase), which was entirely degraded during the incubation time. Although differences among harvests and years were evident, genetic variation among the 10 diploid perennial grass samples concerning protein degradation rates and degradation characteristics was not detected.

Protein degradation rate as affected by plant proteases among fresh samples of perennial ryegrass cultivars (<italic>Lolium perenne</italic> L.) / Einfluss pflanzlicher Proteasen auf den Proteinabbau bei unterschiedlichen Englischen Raigrass Sorten (<italic>Lolium perenne</italic> L.)

Institute of Animal Nutrition, Livestock Products and Nutrition Physiology (TTE) Department of Agrobiotechnology, IFA-Tulln, University of Natural Resources and Life Sciences, Vienna,

Grass and Forage Science/Organic Agriculture Group, Institute of Crop Science and Plant Breeding, University of Kiel,

Die Bodenkultur: Journal of Land Management, Food and Environment

This article is distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Protein degradation rate as affected by plant proteases among fresh samples of perennial ryegrass cultivars ( L.) / Einfluss pflanzlicher Proteasen auf den Proteinabbau bei unterschiedlichen Englischen Raigrass Sorten ( L.)

The objective of this study was to quantify the proteolytic activity of a set of 10 diploid early intermediate heading cultivars of Lolium perenne under...

	Incubation time
	0 h	6 h	24 h
Protein content, µg g⁻¹ FM				SEM
First cut	93.9^{a A}	31.2^{b A}	11.1^{c A}	3.12
Second cut	95.3^{a A}	26.9^{b B}	9.6^{c A}	3.12

Item	Cultivar										SEM	Sign.
Item	1	2	3	4	5	6	7	8	9	10	SEM	Sign.
Degradation rate
0–6 h	0.20	0.22	0.19	0.18	0.20	0.22	0.19	0.22	0.21	0.19	0.012	n.s.
6–24 h	0.08	0.06	0.06	0.06	0.07	0.07	0.06	0.06	0.07	0.06	0.006	n.s.
0–24 h	0.10	0.09	0.09	0.08	0.10	0.10	0.08	0.09	0.10	0.09	0.005	n.s.

Protein degradation rate as affected by plant proteases among fresh samples of perennial ryegrass cultivars (Lolium perenne L.) / Einfluss pflanzlicher Proteasen auf den Proteinabbau bei unterschiedlichen Englischen Raigrass Sorten (Lolium perenne L.)

Article Category: Research Article

Published Online: Sep 08, 2016

Page range: 61 - 68

Received: Jan 20, 2016

Accepted: Feb 09, 2016

DOI: https://doi.org/10.1515/boku-2016-0006

Keywords
rumenlike conditions, Rubisco, plant protease, N-use efficiency

© 2016 De Gruyter, www.degruyter.com/view/j/boku

This article is distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

The protein content in grass leaves as affected by incubation time and harvest as means over 10 genotypesTabelle 1. Einfluss von Inkubationszeit und Erntezeitpunkt auf den Proteingehalt in Blättern als Mittelwert über 10 Genotypen

Fractional degradation rate of the logarithmic-transformed protein contents of the tested cultivars per hour incubationTabelle 2. Proportionale Abbaurate des logarithmisch transformierten Proteingehaltes der geprüften Genotypen

Protein degradation rate as affected by plant proteases among fresh samples of perennial ryegrass cultivars (Lolium perenne L.) / Einfluss pflanzlicher Proteasen auf den Proteinabbau bei unterschiedlichen Englischen Raigrass Sorten (Lolium perenne L.)

Article Category: Research Article

Published Online: Sep 08, 2016

Page range: 61 - 68

Received: Jan 20, 2016

Accepted: Feb 09, 2016

DOI: https://doi.org/10.1515/boku-2016-0006

Keywordsrumenlike conditions, Rubisco, plant protease, N-use efficiency

© 2016 De Gruyter, www.degruyter.com/view/j/boku

This article is distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

The protein content in grass leaves as affected by incubation time and harvest as means over 10 genotypesTabelle 1. Einfluss von Inkubationszeit und Erntezeitpunkt auf den Proteingehalt in Blättern als Mittelwert über 10 Genotypen

Fractional degradation rate of the logarithmic-transformed protein contents of the tested cultivars per hour incubationTabelle 2. Proportionale Abbaurate des logarithmisch transformierten Proteingehaltes der geprüften Genotypen

Keywords
rumenlike conditions, Rubisco, plant protease, N-use efficiency