Abstract
Application of exogenous ethylene in combination with gibberellic acid (GA(3)), kinetin (KIN), and/or CO(2) has been reported to induce germination of lettuce seeds at supraoptimal temperatures. However, it is not clear whether endogenous ethylene also plays a mediatory role when germination under these conditions is induced by treatment regimes that do not include ethylene. Therefore, possible involvement of endogenous ethylene during the relief of thermoinhibition of lettuce (Lactuca sativa L. cv Grand Rapids) seed germination at 32 degrees C was investigated. Combinations of GA(3) (0.5 millimolar), KIN (0.05 millimolar), and CO(2) (10%) were used to induce germination. Little germination occurred in controls or upon treatment with ethylene, KIN, or CO(2). Neither KIN nor CO(2) affected the rate of ethylene production by seeds. Both germination and ethylene production were slightly promoted by GA(3). Treatments with GA(3)+CO(2), GA(3)+KIN, or GA(3)+CO(2)+KIN resulted in approximately 10-to 40-fold increases in ethylene production and 50 to 100% promotion of germination as compared to controls. Initial ethylene evolution from the treated seeds was greater than from the controls and a major surge in ethylene evolution occurred at the time of visible germination. Application of 1 millimolar 2-aminoethoxyvinyl glycine (AVG), an inhibitor of ethylene synthesis, in combination with any of above three treatments inhibited the ethylene production to below control levels. This was accompanied by a marked decline in germination percentage. Germination was also inhibited by 2,5-norbornadiene (0.25-2 milliliters per liter), a competitive inhibitor of ethylene action. Application of exogenous ethylene (1-100 microliters per liter) overcame the inhibitory effects of AVG and 2,5-norbornadiene on germination. The results demonstrate that endogenous ethylene synthesis and action are essential for the alleviation of thermoinhibition of lettuce seeds by combinations of GA(3), KIN, and CO(2). It also appears that these treatment combinations do not act exclusively via promotion of ethylene evolution as the application of exogenous ethylene alone did not promote germination.
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Claims 18
Claim · model-written summary
Controls and single ethylene, kinetin or CO2 treatments produced little lettuce germination.
- Taxon
- lettuce
Lactuca sativat0 - Treatment
- ethylene, KIN, or CO(2)e0
- Outcome
- germinatione0
- Direction
- Littlee0
- Comparator
- controlse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Little germination occurred in controls or upon treatment with ethylene, KIN, or CO(2)”
t0“Lettuce Seed Germination”
Claim · model-written summary
KIN did not affect seed ethylene production.
- Taxon
- lettuceLactuca sativat0
- Treatment
- KINe0
- Outcome
- rate of ethylene production by seedse0
- Direction
- Neithere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Neither KIN nor CO(2) affected the rate of ethylene production by seeds”
t0“Lettuce Seed Germination”
Claim · model-written summary
CO2 did not affect seed ethylene production.
- Taxon
- lettuceLactuca sativat0
- Treatment
- CO(2)e0
- Outcome
- rate of ethylene production by seedse0
- Direction
- Neithere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Neither KIN nor CO(2) affected the rate of ethylene production by seeds”
t0“Lettuce Seed Germination”
Claim · model-written summary
GA3 slightly promoted germination and ethylene production.
- Taxon
- lettuceLactuca sativat0
- Treatment
- GA(3)e0
- Outcome
- germination and ethylene productione0
- Direction
- promotede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Both germination and ethylene production were slightly promoted by GA(3)”
t0“Lettuce Seed Germination”
Claim · model-written summary
GA3 plus CO2 increased ethylene production approximately 10 to 40 fold.
- Taxon
- lettuceLactuca sativat0
- Treatment
- GA(3)+CO(2)e0
- Outcome
- ethylene productione0
- Direction
- increasese0
- Value
- 10-to 40-folde0
- Comparator
- controlse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Treatments with GA(3)+CO(2), GA(3)+KIN, or GA(3)+CO(2)+KIN resulted in approximately 10-to 40-fold increases in ethylene production and 50 to 100% promotion of germination as compared to controls”
t0“Lettuce Seed Germination”
Claim · model-written summary
GA3 plus kinetin increased ethylene production approximately 10 to 40 fold.
- Taxon
- lettuceLactuca sativat0
- Treatment
- GA(3)+KINe0
- Outcome
- ethylene productione0
- Direction
- increasese0
- Value
- 10-to 40-folde0
- Comparator
- controlse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Treatments with GA(3)+CO(2), GA(3)+KIN, or GA(3)+CO(2)+KIN resulted in approximately 10-to 40-fold increases in ethylene production and 50 to 100% promotion of germination as compared to controls”
t0“Lettuce Seed Germination”
Claim · model-written summary
GA3, CO2 and kinetin increased ethylene production approximately 10 to 40 fold.
- Taxon
- lettuceLactuca sativat0
- Treatment
- GA(3)+CO(2)+KINe0
- Outcome
- ethylene productione0
- Direction
- increasese0
- Value
- 10-to 40-folde0
- Comparator
- controlse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Treatments with GA(3)+CO(2), GA(3)+KIN, or GA(3)+CO(2)+KIN resulted in approximately 10-to 40-fold increases in ethylene production and 50 to 100% promotion of germination as compared to controls”
t0“Lettuce Seed Germination”
Claim · model-written summary
GA3 plus CO2 promoted germination by 50 to 100%.
- Taxon
- lettuceLactuca sativat0
- Treatment
- GA(3)+CO(2)e0
- Outcome
- germinatione0
- Direction
- promotione0
- Value
- 50 to 100%e0
- Comparator
- controlse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Treatments with GA(3)+CO(2), GA(3)+KIN, or GA(3)+CO(2)+KIN resulted in approximately 10-to 40-fold increases in ethylene production and 50 to 100% promotion of germination as compared to controls”
t0“Lettuce Seed Germination”
Claim · model-written summary
GA3 plus kinetin promoted germination by 50 to 100%.
- Taxon
- lettuceLactuca sativat0
- Treatment
- GA(3)+KINe0
- Outcome
- germinatione0
- Direction
- promotione0
- Value
- 50 to 100%e0
- Comparator
- controlse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Treatments with GA(3)+CO(2), GA(3)+KIN, or GA(3)+CO(2)+KIN resulted in approximately 10-to 40-fold increases in ethylene production and 50 to 100% promotion of germination as compared to controls”
t0“Lettuce Seed Germination”
Claim · model-written summary
GA3, CO2 and kinetin promoted germination by 50 to 100%.
- Taxon
- lettuceLactuca sativat0
- Treatment
- GA(3)+CO(2)+KINe0
- Outcome
- germinatione0
- Direction
- promotione0
- Value
- 50 to 100%e0
- Comparator
- controlse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Treatments with GA(3)+CO(2), GA(3)+KIN, or GA(3)+CO(2)+KIN resulted in approximately 10-to 40-fold increases in ethylene production and 50 to 100% promotion of germination as compared to controls”
t0“Lettuce Seed Germination”
Claim · model-written summary
Treated lettuce seeds had greater initial ethylene evolution than controls.
- Taxon
- lettuceLactuca sativat0
- Treatment
- treated seedse0
- Outcome
- Initial ethylene evolutione0
- Direction
- greatere0
- Comparator
- controlse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Initial ethylene evolution from the treated seeds was greater than from the controls”
t0“Lettuce Seed Germination”
Claim · model-written summary
A major ethylene surge coincided with visible germination.
- Taxon
- lettuceLactuca sativat0
- Outcome
- surge in ethylene evolutione0
- Direction
- surgee0
- Qualifier
- at the time of visible germinatione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a major surge in ethylene evolution occurred at the time of visible germination”
t0“Lettuce Seed Germination”
Claim · model-written summary
AVG with the combination treatments lowered ethylene production below controls.
- Taxon
- lettuceLactuca sativat0
- Treatment
- 1 millimolar 2-aminoethoxyvinyl glycine (AVG)e0
- Outcome
- ethylene productione0
- Direction
- inhibitede0
- Comparator
- control levelse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Application of 1 millimolar 2-aminoethoxyvinyl glycine (AVG), an inhibitor of ethylene synthesis, in combination with any of above three treatments inhibited the ethylene production to below control levels”
t0“Lettuce Seed Germination”
Claim · model-written summary
AVG with the combination treatments markedly reduced germination.
- Taxon
- lettuceLactuca sativat0
- Treatment
- AVGe1
- Outcome
- germination percentagee0
- Direction
- declinee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“This was accompanied by a marked decline in germination percentage”
t0“Lettuce Seed Germination”
e1“2-aminoethoxyvinyl glycine (AVG), an inhibitor of ethylene synthesis”
Claim · model-written summary
Norbornadiene inhibited germination.
- Taxon
- lettuceLactuca sativat0
- Treatment
- 2,5-norbornadiene (0.25-2 milliliters per liter)e0
- Outcome
- Germinatione0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Germination was also inhibited by 2,5-norbornadiene (0.25-2 milliliters per liter)”
t0“Lettuce Seed Germination”
Claim · model-written summary
Exogenous ethylene overcame AVG inhibition of germination.
- Taxon
- lettuceLactuca sativat0
- Treatment
- exogenous ethylene (1-100 microliters per liter)e0
- Outcome
- germinatione0
- Direction
- overcamee0
- Comparator
- AVGe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Application of exogenous ethylene (1-100 microliters per liter) overcame the inhibitory effects of AVG and 2,5-norbornadiene on germination”
t0“Lettuce Seed Germination”
Claim · model-written summary
Exogenous ethylene overcame norbornadiene inhibition of germination.
- Taxon
- lettuceLactuca sativat0
- Treatment
- exogenous ethylene (1-100 microliters per liter)e0
- Outcome
- germinatione0
- Direction
- overcamee0
- Comparator
- 2,5-norbornadienee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Application of exogenous ethylene (1-100 microliters per liter) overcame the inhibitory effects of AVG and 2,5-norbornadiene on germination”
t0“Lettuce Seed Germination”
Claim · model-written summary
Endogenous ethylene synthesis and action were necessary for combination treatments to relieve thermoinhibition.
- Taxon
- lettuceLactuca sativat0
- Outcome
- alleviation of thermoinhibitione0
- Qualifier
- endogenous ethylene synthesis and actione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“endogenous ethylene synthesis and action are essential for the alleviation of thermoinhibition of lettuce seeds by combinations of GA(3), KIN, and CO(2)”
t0“Lettuce Seed Germination”
The same questions in other papers
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See all 6 papers →8 of 9 groups shown: named compounds and organisms first, then groups whose results differ (checked claim by claim), then those with positive and negative results, then the smaller groups.
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.