Abstract
Water stress is a major limiting factor for sunflower production in the arid and semi arid regions in the world. In order to study the effects of sowing date and limited irrigation stress on plant height, head diameter, seed number per head, thousand seed weight, seed yield, biologic yield and harvest index of spring sunflower cultivar (Mehr), an experiment was conducted using a split plot arrangement based on randomised complete block design with three replications in Karaj, Iran, during 2008 and 2009.The present study showed that optimal environmental conditions around reproductive stages, provided by early sowing not only enhanced plant growth but also produced higher yield compared with those of late sowing dates. The April 20 th and May 9 th sowing produced larger seed yield, biologic yield and harvest index with no water stress treatment compared to late May sowing date with limited irrigation stress at stem elongation, flowering and grain filling stages respectively. The results showed that the limited irrigation stress resulted in reduction of seed yield due to limited vegetative and reproductive development. It is of prior concern to consider optimum sowing date so that high temperature of late sowing would not coincide with the reproductive stages of sunflower.
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Claims 7
Claim · model-written summary
Early sowing enhanced sunflower growth relative to late sowing.
- Taxon
- sunflower
Helianthus annuust0 - Treatment
- early sowinge0
- Outcome
- plant growthe0
- Direction
- enhancede0
- Comparator
- late sowing datese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“early sowing not only enhanced plant growth but also produced higher yield compared with those of late sowing dates”
t0“sunflower”
Claim · model-written summary
Early sowing produced higher sunflower yield than late sowing.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- early sowinge0
- Outcome
- yielde0
- Direction
- highere0
- Comparator
- late sowing datese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“early sowing not only enhanced plant growth but also produced higher yield compared with those of late sowing dates”
t0“sunflower”
Claim · model-written summary
April 20 and May 9 sowing without water stress produced larger seed yield than late May sowing under limited irrigation.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- April 20 th and May 9 th sowinge0
- Outcome
- seed yielde0
- Direction
- largere0
- Comparator
- late May sowing date with limited irrigation stresse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The April 20 th and May 9 th sowing produced larger seed yield, biologic yield and harvest index with no water stress treatment compared to late May sowing date with limited irrigation stress at stem elongation, flowering and grain filling stages respectively.”
t0“sunflower”
Claim · model-written summary
April 20 and May 9 sowing without water stress produced larger biologic yield than late May sowing under limited irrigation.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- April 20 th and May 9 th sowinge0
- Outcome
- biologic yielde0
- Direction
- largere0
- Comparator
- late May sowing date with limited irrigation stresse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The April 20 th and May 9 th sowing produced larger seed yield, biologic yield and harvest index with no water stress treatment compared to late May sowing date with limited irrigation stress at stem elongation, flowering and grain filling stages respectively.”
t0“sunflower”
Claim · model-written summary
April 20 and May 9 sowing without water stress produced a larger harvest index than late May sowing under limited irrigation.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- April 20 th and May 9 th sowinge0
- Outcome
- harvest indexe0
- Direction
- largere0
- Comparator
- late May sowing date with limited irrigation stresse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The April 20 th and May 9 th sowing produced larger seed yield, biologic yield and harvest index with no water stress treatment compared to late May sowing date with limited irrigation stress at stem elongation, flowering and grain filling stages respectively.”
t0“sunflower”
Claim · model-written summary
Limited irrigation stress reduced sunflower seed yield.
- Taxon
- sunflowerHelianthus annuust0
- Treatment
- limited irrigation stresse0
- Outcome
- seed yielde0
- Direction
- reductione0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the limited irrigation stress resulted in reduction of seed yield due to limited vegetative and reproductive development”
t0“sunflower”
Claim · model-written summary
The authors recommend an optimum sowing date that avoids high temperature during sunflower reproductive stages.
- Taxon
- sunflowerHelianthus annuuse0
- Outcome
- optimum sowing datee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“It is of prior concern to consider optimum sowing date so that high temperature of late sowing would not coincide with the reproductive stages of sunflower.”
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See all 165 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.