Abstract
Biostimulants such as humic acid (HA), salicylic acid (SA), and ascorbic acid (ASA) have gained increasing attention for enhancing crop resilience and productivity. However, their effectiveness is strongly influenced by environmental and nutritional contexts. A field experiment was conducted in two contrasting climates of Iran—semi-humid (Khorramabad) and arid (Mashhad)—to evaluate the combined effects of nitrogen sources and foliar biostimulants on physiological, biochemical, and yield traits of cluster bean (Cyamopsis tetragonoloba L.). The experiment was conducted as a factorial arrangement within a randomized complete block design with three replications. The first factor included five nitrogen treatments: control (no N), urea (69 kg N ha−1), ammonium nitrate (115 kg N ha−1), vermicompost (8 t ha−1; equivalent to 120 kg N ha−1), and biological N fertilizer containing Azotobacter spp. (Azetobarvar). The second factor comprised four foliar spray treatments: distilled water (control), HA (0.2 g L−1), ASA (200 mg L−1), and SA (200 µM). Significant three-way interactions among location, fertilizer, and biostimulant were observed for photosynthesis rate, pigments, biochemical compositions, and yield. Urea + HA consistently produced the highest photosynthetic rate and seed yield (up to 3526 kg ha−1), whereas SA enhanced stress tolerance and protein content under arid conditions. Correlation analysis showed that seed yield was positively associated with photosynthesis rate (r = 0.35**) and biological yield (r = 0.89**). Overall, HA maximized nutrient use efficiency in favorable environments, while SA and ASA enhanced biochemical performance. These findings underscore the potential of integrated nitrogen–biostimulant management for sustainable legume production across diverse climates.
Abstract from the paper’s OpenAlex record; open copy licensed cc-by-nc-nd. 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 10
Claim · model-written summary
Location, fertilizer, and biostimulant had a significant three-way interaction for photosynthesis rate, pigments, biochemical composition, and yield.
- Taxon
- cluster bean (Cyamopsis tetragonoloba L.)
Cyamopsis tetragonolobat0 - Treatment
- fertilizer, and biostimulante0
- Outcome
- photosynthesis rate, pigments, biochemical compositions, and yielde0
- Setting
- locatione0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Significant three-way interactions among location, fertilizer, and biostimulant were observed for photosynthesis rate, pigments, biochemical compositions, and yield.”
t0“cluster bean (Cyamopsis tetragonoloba L.)”
Claim · model-written summary
Urea plus humic acid produced the highest photosynthetic rate in cluster bean.
- Taxon
- cluster bean (Cyamopsis tetragonoloba L.)Cyamopsis tetragonolobat0
- Treatment
- Urea + HAe0
- Outcome
- photosynthetic ratee0
- Direction
- higheste0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Urea + HA consistently produced the highest photosynthetic rate and seed yield (up to 3526 kg ha−1)”
t0“cluster bean (Cyamopsis tetragonoloba L.)”
Claim · model-written summary
Urea plus humic acid produced the highest cluster bean seed yield, up to 3526 kg ha−1.
- Taxon
- cluster bean (Cyamopsis tetragonoloba L.)Cyamopsis tetragonolobat0
- Treatment
- Urea + HAe0
- Outcome
- seed yielde0
- Direction
- higheste0
- Value
- 3526 kg ha−1e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Urea + HA consistently produced the highest photosynthetic rate and seed yield (up to 3526 kg ha−1)”
t0“cluster bean (Cyamopsis tetragonoloba L.)”
Claim · model-written summary
Salicylic acid enhanced cluster bean stress tolerance under arid conditions.
- Taxon
- cluster bean (Cyamopsis tetragonoloba L.)Cyamopsis tetragonolobat0
- Treatment
- SAe0
- Outcome
- stress tolerancee0
- Direction
- enhancede0
- Setting
- arid conditionse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“SA enhanced stress tolerance and protein content under arid conditions.”
t0“cluster bean (Cyamopsis tetragonoloba L.)”
Claim · model-written summary
Salicylic acid enhanced cluster bean protein content under arid conditions.
- Taxon
- cluster bean (Cyamopsis tetragonoloba L.)Cyamopsis tetragonolobat0
- Treatment
- SAe0
- Outcome
- protein contente0
- Direction
- enhancede0
- Setting
- arid conditionse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“SA enhanced stress tolerance and protein content under arid conditions.”
t0“cluster bean (Cyamopsis tetragonoloba L.)”
Claim · model-written summary
Cluster bean seed yield was positively associated with photosynthesis rate (r = 0.35**).
- Taxon
- cluster bean (Cyamopsis tetragonoloba L.)Cyamopsis tetragonolobat0
- Outcome
- seed yielde0
- Direction
- positively associatede0
- Value
- r = 0.35**e0
- Qualifier
- photosynthesis ratee0
Not reportedCompound
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“seed yield was positively associated with photosynthesis rate (r = 0.35**)”
t0“cluster bean (Cyamopsis tetragonoloba L.)”
Claim · model-written summary
Cluster bean seed yield was positively associated with biological yield (r = 0.89**).
- Taxon
- cluster bean (Cyamopsis tetragonoloba L.)Cyamopsis tetragonolobat0
- Outcome
- seed yielde0
- Direction
- positively associatede0
- Value
- r = 0.89**e0
- Qualifier
- biological yielde0
Not reportedSetting
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“seed yield was positively associated with photosynthesis rate (r = 0.35**) and biological yield (r = 0.89**)”
t0“cluster bean (Cyamopsis tetragonoloba L.)”
Claim · model-written summary
Humic acid maximized nutrient use efficiency in favorable environments.
- Taxon
- cluster bean (Cyamopsis tetragonoloba L.)Cyamopsis tetragonolobat0
- Treatment
- HAe0
- Outcome
- nutrient use efficiencye0
- Direction
- maximizede0
- Setting
- favorable environmentse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“HA maximized nutrient use efficiency in favorable environments”
t0“cluster bean (Cyamopsis tetragonoloba L.)”
Claim · model-written summary
Salicylic acid enhanced biochemical performance in cluster bean.
- Taxon
- cluster bean (Cyamopsis tetragonoloba L.)Cyamopsis tetragonolobat0
- Treatment
- SAe0
- Outcome
- biochemical performancee0
- Direction
- enhancede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“SA and ASA enhanced biochemical performance.”
t0“cluster bean (Cyamopsis tetragonoloba L.)”
Claim · model-written summary
Ascorbic acid enhanced biochemical performance in cluster bean.
- Taxon
- cluster bean (Cyamopsis tetragonoloba L.)Cyamopsis tetragonolobat0
- Treatment
- ASAe0
- Outcome
- biochemical performancee0
- Direction
- enhancede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“SA and ASA enhanced biochemical performance.”
t0“cluster bean (Cyamopsis tetragonoloba L.)”
The same questions in other papers
salicylic acid · quality: protein · Cyamopsis tetragonoloba (cluster bean)Results agree
1 paper in the same direction as this paper
- positive
nitrogen · yield · Cyamopsis tetragonoloba (cluster bean)Positive and negative results
27 papers in the same direction as this paper · 1 in the opposite direction
- negative
- positive
- positive
25 papers more in this group
See all 29 papers →other · physiology: photosynthesis · Cyamopsis tetragonoloba (cluster bean)Results agree
1 paper in the same direction as this paper
- positive
nitrogen · physiology: photosynthesis · Cyamopsis tetragonoloba (cluster bean)Results agree
1 paper in the same direction as this paper
- positive
other · yield · Cyamopsis tetragonoloba (cluster bean)Results agree
3 papers in the same direction as this paper
- positive
- positive
- positive
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.