Abstract
This vegetative experiment was carried out at the greenhouse of Vytautas Magnus University Agriculture Academy Open Access Joint Research Centre of Agriculture and Forestry (Lithuania) in 2020–2021. The aim of these studies was to determine the effect of different nitrogen rates on the productivity and nutritional quality of forage grasses (a mixture of red clover and timothy) under the most common extremes of climate change, i.e., soil moisture deficiency and surplus. Under drought and waterlogging stresses, fertilization of the red clover and timothy mixture with high N rates was ineffective. The clover and timothy mixture recovery after drought took 21 days. The aboveground dry biomass of the clover and timothy mixture grown under drought conditions was significantly lower by 36.3 to 47.2% compared to that formed under optimum soil moisture and waterlogging conditions. The root biomass of forage grass mixtures was lowest under drought conditions when fertilized at the highest N rate (N25+120). The aboveground biomass of clover grown under different soil moisture conditions depended on the number of plants (r2 = 0.78, p < 0.01) and assimilating leaf area (r2 = 0.83, p < 0.01), and that of timothy on the number of vegetative tillers (r2 = 0.46, p < 0.05). Under drought simulation conditions, increasing the N rate increased the crude protein and crude fibre contents in the aboveground biomass of the clover and timothy mixture, while the crude ash content decreased.
Abstract from the paper’s OpenAlex record; open copy licensed cc-by. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 9
Claim · model-written summary
High nitrogen rates were ineffective under drought and waterlogging.
- Taxon
- red clover and timothy
Phleum pratense
Trifolium pratensee0 - Treatment
- high N ratese0
- Outcome
- ineffectivee0
- Direction
- ineffectivee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Under drought and waterlogging stresses, fertilization of the red clover and timothy mixture with high N rates was ineffective”
Claim · model-written summary
Recovery after drought took 21 days.
- Taxon
- clover and timothy
TrifoliumPhleum pratensee0 - Outcome
- recovery after droughte0
- Value
- 21 dayse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The clover and timothy mixture recovery after drought took 21 days”
Claim · model-written summary
Drought reduced aboveground dry biomass by 36.3 to 47.2% relative to optimum moisture and waterlogging.
- Taxon
- clover and timothyTrifoliumPhleum pratensee0
- Treatment
- drought conditionse0
- Outcome
- aboveground dry biomasse0
- Direction
- lowere0
- Value
- 36.3 to 47.2%e0
- Comparator
- optimum soil moisture and waterlogging conditionse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The aboveground dry biomass of the clover and timothy mixture grown under drought conditions was significantly lower by 36.3 to 47.2% compared to that formed under optimum soil moisture and waterlogging conditions”
Claim · model-written summary
At the highest nitrogen rate, drought produced the lowest root biomass.
- Taxon
- red clover and timothyPhleum pratenseTrifolium pratenset0
- Treatment
- drought conditionse0
- Outcome
- root biomasse0
- Direction
- loweste0
- Qualifier
- highest N rate (N25+120)e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The root biomass of forage grass mixtures was lowest under drought conditions when fertilized at the highest N rate (N25+120)”
t0“red clover and timothy mixture”
Claim · model-written summary
Clover aboveground biomass depended on plant number.
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The aboveground biomass of clover grown under different soil moisture conditions depended on the number of plants (r2 = 0.78, p < 0.01)”
Claim · model-written summary
Clover aboveground biomass depended on assimilating leaf area.
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“and assimilating leaf area (r2 = 0.83, p < 0.01)”
t0“aboveground biomass of clover grown under different soil moisture conditions”
Claim · model-written summary
Timothy aboveground biomass depended on vegetative tiller number.
- Taxon
- timothyPhleum pratensee0
- Organ / stage
- vegetative tillerse0
- Outcome
- number of vegetative tillerse0
- Value
- r2 = 0.46e0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“and that of timothy on the number of vegetative tillers (r2 = 0.46, p < 0.05)”
Claim · model-written summary
With simulated drought, rising nitrogen increased crude protein and fibre.
- Taxon
- clover and timothyTrifoliumPhleum pratensee0
- Treatment
- increasing the N ratee0
- Outcome
- crude protein and crude fibre contentse0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Under drought simulation conditions, increasing the N rate increased the crude protein and crude fibre contents in the aboveground biomass of the clover and timothy mixture”
Claim · model-written summary
With simulated drought, rising nitrogen decreased crude ash.
- Taxon
- clover and timothyTrifoliumPhleum pratensee1
- Treatment
- increasing the N ratee1
- Outcome
- crude ash contente0
- Direction
- decreasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“while the crude ash content decreased”
e1“Under drought simulation conditions, increasing the N rate increased the crude protein and crude fibre contents in the aboveground biomass of the clover and timothy mixture”
The same questions in other papers
drought · growth · Phleum pratense (timothy)Positive and negative results
1 in the opposite direction
- positive
nitrogen · quality: protein · TrifoliumPositive and negative results
1 paper in the same direction as this paper · 2 in the opposite direction
- no effect
- negative
- positive
drought · growth · TrifoliumResults agree
1 paper in the same direction as this paper
- negative
nitrogen · quality: protein · Phleum pratense (timothy)Results agree
2 papers in the same direction as this paper
- positive
- positive
drought · growth · Trifolium pratense (red clover)Results agree
3 papers in the same direction as this paper
- negative
- negative
- negative
Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.