Abstract
Water scarcity and soil salinization are major challenges for sustainable agriculture in arid regions, affecting crop growth, yield, and quality. In greenhouse systems, optimizing irrigation and nutrient management under brackish (slightly to moderately saline) irrigation water (1–5 g L−1) is essential for maintaining productivity and resource efficiency. This study investigated the effects of irrigation water salinity, irrigation volume, and nitrogen, phosphorus, and potassium application on growth, yield, fruit quality, and water–nutrient use efficiency of greenhouse-grown pepper (Capsicum annuum L., cv. ‘Qilin 99’) in southern Xinjiang. A five-factor, five-level half-fractional quadratic orthogonal rotatable design was employed. Pepper yield showed a unimodal response to increasing salinity, peaking at 3 g L−1 with 4800 m3 ha−1 irrigation and N, P2O5, K2O rates of 225, 160, and 500 kg ha−1, respectively. Water use efficiency and fertilizer partial factor productivity decreased significantly with increasing salinity and irrigation amount, reaching maximum under moderate irrigation water mineralization combined with low and medium irrigation levels, respectively. Fruit quality traits, including vitamin C, capsaicin, and free amino acids, were enhanced under moderate to relatively high salinity levels, whereas fruit size and single fruit weight were highest at lower salinity combined with higher irrigation. Irrigation water salinity was identified as the main limiting factor for yield and quality. Overall, greenhouse pepper exhibited a nonlinear dual-threshold response to combined water, nutrient, and salinity management, with an optimal threshold around 3 g L−1. These findings provide practical guidance for improving water and nutrient use efficiency in greenhouse agriculture under slightly saline irrigation.
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 8
Claim · model-written summary
Pepper yield showed a unimodal response to increasing salinity, peaking at 3 g L−1.
- Taxon
- Capsicum annuum
Capsicum annuume2 - Material
- Qilin 99e2
- Treatment
- increasing salinitye1
- Outcome
- Pepper yielde1
- Direction
- unimodal responsee1
- Qualifier
- peaking at 3 g L−1e1
- Setting
- southern Xinjiange2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Pepper yield showed a unimodal response to increasing salinity, peaking at 3 g L−1 with 4800 m3 ha−1 irrigation and N, P2O5, K2O rates of 225, 160, and 500 kg ha−1, respectively”
e2“greenhouse-grown pepper (Capsicum annuum L., cv. ‘Qilin 99’) in southern Xinjiang”
Claim · model-written summary
Water use efficiency and fertilizer partial factor productivity decreased significantly with increasing salinity and irrigation amount.
- Taxon
- Capsicum annuumCapsicum annuume2
- Treatment
- increasing salinity and irrigation amounte3
- Outcome
- Water use efficiency and fertilizer partial factor productivitye3
- Direction
- decreasede3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“greenhouse-grown pepper (Capsicum annuum L., cv. ‘Qilin 99’) in southern Xinjiang”
e3“Water use efficiency and fertilizer partial factor productivity decreased significantly with increasing salinity and irrigation amount”
Claim · model-written summary
Water use efficiency reached its maximum under moderate irrigation water mineralization combined with low irrigation levels.
- Taxon
- Capsicum annuumCapsicum annuume2
- Treatment
- moderate irrigation water mineralizatione4
- Outcome
- Water use efficiencye3
- Direction
- reaching maximume4
- Qualifier
- combined with low and medium irrigation levels, respectivelye4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“greenhouse-grown pepper (Capsicum annuum L., cv. ‘Qilin 99’) in southern Xinjiang”
e3“Water use efficiency and fertilizer partial factor productivity decreased significantly with increasing salinity and irrigation amount”
e4“reaching maximum under moderate irrigation water mineralization combined with low and medium irrigation levels, respectively”
Claim · model-written summary
Fertilizer partial factor productivity reached its maximum under moderate irrigation water mineralization combined with medium irrigation levels.
- Taxon
- Capsicum annuumCapsicum annuume2
- Treatment
- moderate irrigation water mineralizatione4
- Outcome
- fertilizer partial factor productivitye3
- Direction
- reaching maximume4
- Qualifier
- combined with low and medium irrigation levels, respectivelye4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“greenhouse-grown pepper (Capsicum annuum L., cv. ‘Qilin 99’) in southern Xinjiang”
e3“Water use efficiency and fertilizer partial factor productivity decreased significantly with increasing salinity and irrigation amount”
e4“reaching maximum under moderate irrigation water mineralization combined with low and medium irrigation levels, respectively”
Claim · model-written summary
Vitamin C, capsaicin and free amino acids were enhanced under moderate to relatively high salinity levels.
- Taxon
- Capsicum annuumCapsicum annuume2
- Treatment
- moderate to relatively high salinity levelse5
- Outcome
- vitamin C, capsaicin, and free amino acidse5
- Direction
- enhancede5
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“greenhouse-grown pepper (Capsicum annuum L., cv. ‘Qilin 99’) in southern Xinjiang”
e5“Fruit quality traits, including vitamin C, capsaicin, and free amino acids, were enhanced under moderate to relatively high salinity levels”
Claim · model-written summary
Fruit size and single fruit weight were highest at lower salinity combined with higher irrigation.
- Taxon
- Capsicum annuumCapsicum annuume2
- Treatment
- lower salinity combined with higher irrigatione6
- Outcome
- fruit size and single fruit weighte6
- Direction
- higheste6
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“greenhouse-grown pepper (Capsicum annuum L., cv. ‘Qilin 99’) in southern Xinjiang”
e6“whereas fruit size and single fruit weight were highest at lower salinity combined with higher irrigation”
Claim · model-written summary
Irrigation water salinity is identified as the main limiting factor for yield and quality.
- Taxon
- Capsicum annuumCapsicum annuume2
- Treatment
- Irrigation water salinitye7
- Outcome
- yield and qualitye7
- Qualifier
- main limiting factore7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e2“greenhouse-grown pepper (Capsicum annuum L., cv. ‘Qilin 99’) in southern Xinjiang”
e7“Irrigation water salinity was identified as the main limiting factor for yield and quality”
Claim · model-written summary
Greenhouse pepper showed a nonlinear dual-threshold response with an optimal threshold around 3 g L−1.
Verbatim
e0“greenhouse pepper exhibited a nonlinear dual-threshold response to combined water, nutrient, and salinity management, with an optimal threshold around 3 g L−1”
The same questions in other papers
salinity · quality: phytochemicals · Capsicum annuum (sweet pepper)Results differ
8 papers in the same direction as this paper · 2 in the opposite direction
- negative
- negative
- positive
7 papers more in this group
See all 11 papers →salinity · yield · Capsicum annuum (sweet pepper)Results differ
2 papers in the same direction as this paper · 22 in the opposite direction
- negative
- negative
- negative
21 papers more in this group
See all 25 papers →irrigation · yield · Capsicum annuum (sweet pepper)Positive and negative results
43 papers in the same direction as this paper · 16 in the opposite direction · 1 reporting no difference from an alternative
- no effect
- negative
- negative
57 papers more in this group
See all 61 papers →salinity · physiology: water · Capsicum annuum (sweet pepper)Results agree
12 papers in the same direction as this paper
- no effect
- negative
- negative
9 papers more in this group
See all 13 papers →irrigation · physiology: water · Capsicum annuum (sweet pepper)Results agree
13 papers in the same direction as this paper
- positive
- positive
- positive
10 papers more in this group
See all 14 papers →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.