Abstract
SUMMARY Apple rootstocks placed in the settling‐tower 24 hr. before introduction of spores of Podosphaera Zeucotricha developed more lesions than those placed in position immediately before inoculation; a period of 24 hr. in the tower after introduction of spores induced more infections than one of 48 hr. Rootstocks kept at high temperature for a few hours immediately on removal from the tower (24 hr. after inoculation) developed only half as many lesions as those maintained at normal temperatures. This effect declined steadily as the heating was applied on successively later days until the 8th day when such heating had no effect. Plants kept at about 20°C. and a relative humidity not exceeding 70% grew satisfactorily and developed very similar numbers of lesions to those inoculated in the same tower but subsequently incubated in a greenhouse where R.H. reached saturation every night. High humidity therefore is unnecessary for the inoculation and development of apple mildew. The leaves initially produced by rootstocks potted in John Innes No. I compost and watered daily with ammonium nitrate solution, were no more susceptible to powdery mildew than those on similar plants given water only. However, when such rootstocks were grown for several weeks, cut back to a few buds, and allowed to break again, the leaves were larger and more susceptible if ammonium nitrate was given as a 0·005 to 0·015 M solution. The susceptibility of leaves on M. III rootstocks decreased with age by about 50% per leaf‐position down to the fourth and even faster below that position, so that the youngest leaf that is just unrolling is by far the most susceptible.
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Claims 9
Claim · model-written summary
Rootstocks placed in the tower 24 hours before spores developed more lesions than those placed immediately before inoculation.
- Taxon
- Apple
Malus domesticae0 - Treatment
- 24 hr. before introduction of sporese0
- Interactor
- Podosphaera Zeucotrichae0pathogen
- Outcome
- lesionse0
- Direction
- moree0
- Comparator
- immediately before inoculatione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Apple rootstocks placed in the settling‐tower 24 hr. before introduction of spores of Podosphaera Zeucotricha developed more lesions than those placed in position immediately before inoculation”
Claim · model-written summary
Twenty-four hours in the tower after spores induced more infections than 48 hours.
- Taxon
- AppleMalus domesticae0
- Treatment
- 24 hr. in the tower after introduction of sporese0
- Interactor
- Podosphaera Zeucotrichae0pathogen
- Outcome
- infectionse0
- Direction
- moree0
- Comparator
- 48 hr.e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Apple rootstocks placed in the settling‐tower 24 hr. before introduction of spores of Podosphaera Zeucotricha developed more lesions than those placed in position immediately before inoculation; a period of 24 hr. in the tower after introduction of spores induced more infections than one of 48 hr.”
Claim · model-written summary
Immediate high temperature after removal halved lesion numbers versus normal temperature.
- Taxon
- AppleMalus domesticat0
- Treatment
- high temperature for a few hours immediately on removal from the towere0
- Outcome
- lesionse0
- Direction
- only half as manye0
- Value
- half as manye0
- Comparator
- normal temperaturese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Rootstocks kept at high temperature for a few hours immediately on removal from the tower (24 hr. after inoculation) developed only half as many lesions as those maintained at normal temperatures.”
t0“Apple rootstocks placed in the settling‐tower”
Claim · model-written summary
The protective effect of heating declined with later application and disappeared by day eight.
- Taxon
- AppleMalus domesticat0
- Treatment
- heatinge0
- Outcome
- effecte0
- Direction
- declined steadilye0
- Value
- 8th daye0
- Comparator
- successively later dayse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“This effect declined steadily as the heating was applied on successively later days until the 8th day when such heating had no effect.”
t0“Apple rootstocks placed in the settling‐tower”
Claim · model-written summary
Plants held at about 20°C and at most 70% relative humidity had lesion counts similar to greenhouse plants.
- Taxon
- AppleMalus domesticat0
- Treatment
- about 20°C. and a relative humidity not exceeding 70%e0
- Outcome
- numbers of lesionse0
- Direction
- very similare0
- Comparator
- greenhouse where R.H. reached saturation every nighte0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Plants kept at about 20°C. and a relative humidity not exceeding 70% grew satisfactorily and developed very similar numbers of lesions to those inoculated in the same tower but subsequently incubated in a greenhouse where R.H. reached saturation every night.”
t0“Apple rootstocks placed in the settling‐tower”
Claim · model-written summary
Initial leaves from daily ammonium nitrate treated plants were no more susceptible than water-only controls.
- Taxon
- AppleMalus domesticat0
- Treatment
- ammonium nitrate solutione0
- Outcome
- susceptible to powdery mildewe0
- Direction
- no more susceptiblee0
- Comparator
- water onlye0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The leaves initially produced by rootstocks potted in John Innes No. I compost and watered daily with ammonium nitrate solution, were no more susceptible to powdery mildew than those on similar plants given water only.”
t0“Apple rootstocks placed in the settling‐tower”
Claim · model-written summary
After prolonged growth and cutting back, ammonium nitrate yielded larger leaves.
- Taxon
- AppleMalus domesticat0
- Treatment
- ammonium nitrate was given as a 0·005 to 0·015 M solutione0
- Outcome
- leavese0
- Direction
- largere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“However, when such rootstocks were grown for several weeks, cut back to a few buds, and allowed to break again, the leaves were larger and more susceptible if ammonium nitrate was given as a 0·005 to 0·015 M solution.”
t0“Apple rootstocks placed in the settling‐tower”
Claim · model-written summary
After prolonged growth and cutting back, ammonium nitrate increased leaf mildew susceptibility.
- Taxon
- AppleMalus domesticat0
- Treatment
- ammonium nitrate was given as a 0·005 to 0·015 M solutione0
- Outcome
- susceptiblee0
- Direction
- more susceptiblee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“However, when such rootstocks were grown for several weeks, cut back to a few buds, and allowed to break again, the leaves were larger and more susceptible if ammonium nitrate was given as a 0·005 to 0·015 M solution.”
t0“Apple rootstocks placed in the settling‐tower”
Claim · model-written summary
M. III rootstock leaf susceptibility fell about 50% per leaf position through the fourth position, then faster.
- Taxon
- AppleMalus domesticat0
- Material
- M. III rootstockse0
- Outcome
- susceptibility of leavese0
- Direction
- decreasede0
- Value
- about 50% per leaf‐positione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The susceptibility of leaves on M. III rootstocks decreased with age by about 50% per leaf‐position down to the fourth and even faster below that position, so that the youngest leaf that is just unrolling is by far the most susceptible.”
t0“Apple rootstocks placed in the settling‐tower”
The same questions in other papers
ammonium nitrate · disease · Malus domestica (apple)Positive and negative results
1 in the opposite direction
- positive
humidity · disease · Malus domestica (apple)Positive and negative results
1 paper in the same direction as this paper · 2 reporting no difference from an alternative
- positive
- positive
- no effect
heat · disease · Malus domestica (apple)Positive and negative results
20 papers in the same direction as this paper · 9 in the opposite direction
- negative
- negative
- negative
26 papers more in this group
See all 30 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.