Abstract
High night temperatures cause excessive floral abscission in cowpea ( Vigna unguiculata (L.) Walp.), while similar or even higher temperatures during the day do not impair reproduction. The objectives of this study were to determine if high temperatures during the early part of the night have different effects on cowpea pod set than high temperatures during the late part of the night, and if distinct events of pollen development are associated with the diurnal sensitivity to heat. Two genotypes of cowpea were grown in controlled environments under a 12‐h photoperiod and subjected to high temperatures (33 °C) during the day and either the first or second 6‐h period of the night. Temperatures were optimal (24 °C) during the other 6 h of the night. All plants experienced the same heat units. Floral buds were sampled at different stages of development and the developing pollen were microscopically examined. For the two genotypes, high temperatures during the late‐night period resulted in much lower pod set (7 and 20%) and pollen viability (2 and 35%) than high temperatures during the early‐night period (51 and 76%, and 65 and 69%, respectively). No diurnal synchrony in pollen development was observed during the late‐night period when developing pollen was the most sensitive to high night temperatures. No changes in floral morphology were observed that could impede pollen transfer from the anthers to the stigma and be responsible for the low pod set. We hypothesize that the results can be explained by the existence of a physiological process that is sensitive to heat and under circadian regulation.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. 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 7
Claim · model-written summary
Late-night heat reduced pod set to 7% in one genotype versus 51% under early-night heat.
- Taxon
- cowpea
Vigna unguiculatat0 - Treatment
- high temperatures during the late‐night periode0
- Outcome
- pod sete0
- Direction
- lowere0
- Value
- 7e0
- Qualifier
- 51e0
- Comparator
- high temperatures during the early‐night periode0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“For the two genotypes, high temperatures during the late‐night period resulted in much lower pod set (7 and 20%) and pollen viability (2 and 35%) than high temperatures during the early‐night period (51 and 76%, and 65 and 69%, respectively)”
t0“Cowpea”
Claim · model-written summary
Late-night heat reduced pod set to 20% in the second genotype versus 76%.
- Taxon
- cowpeaVigna unguiculatat0
- Treatment
- high temperatures during the late‐night periode0
- Outcome
- pod sete0
- Direction
- lowere0
- Value
- 20%e0
- Qualifier
- 76%e0
- Comparator
- high temperatures during the early‐night periode0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“For the two genotypes, high temperatures during the late‐night period resulted in much lower pod set (7 and 20%) and pollen viability (2 and 35%) than high temperatures during the early‐night period (51 and 76%, and 65 and 69%, respectively)”
t0“Cowpea”
Claim · model-written summary
Late-night heat reduced pollen viability to 2% in one genotype versus 65%.
- Taxon
- cowpeaVigna unguiculatat0
- Treatment
- high temperatures during the late‐night periode0
- Outcome
- pollen viabilitye0
- Direction
- lowere0
- Value
- 2e0
- Qualifier
- 65e0
- Comparator
- high temperatures during the early‐night periode0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“For the two genotypes, high temperatures during the late‐night period resulted in much lower pod set (7 and 20%) and pollen viability (2 and 35%) than high temperatures during the early‐night period (51 and 76%, and 65 and 69%, respectively)”
t0“Cowpea”
Claim · model-written summary
Late-night heat reduced pollen viability to 35% in the second genotype versus 69%.
- Taxon
- cowpeaVigna unguiculatat0
- Treatment
- high temperatures during the late‐night periode0
- Outcome
- pollen viabilitye0
- Direction
- lowere0
- Value
- 35%e0
- Qualifier
- 69%e0
- Comparator
- high temperatures during the early‐night periode0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“For the two genotypes, high temperatures during the late‐night period resulted in much lower pod set (7 and 20%) and pollen viability (2 and 35%) than high temperatures during the early‐night period (51 and 76%, and 65 and 69%, respectively)”
t0“Cowpea”
Claim · model-written summary
No diurnal synchrony in pollen development was observed during the sensitive late-night period.
- Taxon
- cowpeaVigna unguiculatat0
- Organ / stage
- developing pollene0
- Outcome
- No diurnal synchrony in pollen developmente0
- Qualifier
- late‐night periode0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“No diurnal synchrony in pollen development was observed during the late‐night period when developing pollen was the most sensitive to high night temperatures”
t0“Cowpea”
Claim · model-written summary
No floral morphology change capable of impeding pollen transfer was observed.
- Taxon
- cowpeaVigna unguiculatat0
- Outcome
- No changes in floral morphologye0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“No changes in floral morphology were observed that could impede pollen transfer from the anthers to the stigma and be responsible for the low pod set”
t0“Cowpea”
Claim · model-written summary
The authors hypothesize a heat-sensitive circadian process explains the results.
- Taxon
- cowpeaVigna unguiculatat0
- Outcome
- resultse0
- Qualifier
- physiological process that is sensitive to heat and under circadian regulatione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“We hypothesize that the results can be explained by the existence of a physiological process that is sensitive to heat and under circadian regulation”
t0“Cowpea”
The same questions in other papers
heat · yield · Vigna unguiculata (cowpea)Positive and negative results
4 papers in the same direction as this paper · 3 in the opposite direction
- positive
- positive
- positive
4 papers more in this group
See all 8 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.