Abstract
Abstract An experiment was conducted to clarify the relationship between Mn toxicity and Fe deficiency in bush snap bean (Phaseolus vulgaris L. cv. ‘Wonder Crop No. 2'). Seedlings were grown in full strength Hoagland No. 2 solution at pH 6.0 for ten days. Six concentrations of Mn as MnCl2.4H2O were used in combination with three concentrations of Fe as FeEDTA. Toxicity symptoms, induced by low levels of Mn (0.1 ppm and above), included: small brown necrotic spots and veinal necrosis on primary leaves; necrosis on primary leaf petioles; interveinal chlorosis, with or without brown necrotic spots, on trifoliate leaves; and brown necrotic spots on stipules. Manganese toxicity symptoms were alleviated or prevented by increasing Fe concentration in the nutrient solution. Manganese concentration in the leaves increased with increasing Mn and decreased with increasing Fe concentration in the nutrient solution, Iron concentration in the roots increased with increasing Fe concentration in the nutrient solution; however, Fe concentration in the leaves was not significantly affected by increasing Mn concentration in the solution culture. Manganese toxicity symptoms developed when Mn concentration in the leaves reached about 120 ppm. A decrease in the Fe/Mn ratio in the nutrient solution resulted in a proportionate decrease in that of the leaves. Manganese toxicity symptoms occurred when the Fe/Mn ratio in the solution was 10.0 and below, or when the ratio in the leaves was less than 1.5. The ratio of Fe/Mn in the solution required for optimum growth of ‘Wonder Crop No. 2’ bean, without Mn toxicity symptoms, was in the range of 20.0 to 25.0. Results indicate that the chlorosis on bush bean leaves induced by excessive Mn in the nutrient solution was due to excessive accumulation of Mn and not to Fe deficiency.
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Claims 15
Claim · model-written summary
Low Mn caused small brown necrotic spots and veinal necrosis on primary leaves.
- Taxon
- bush beant0
- Treatment
- low levels of Mn (0.1 ppm and above)e0
- Outcome
- small brown necrotic spots and veinal necrosis on primary leavese0
Not reportedComparatorDirection
Verbatim
t0“bush bean”
e0“Toxicity symptoms, induced by low levels of Mn (0.1 ppm and above), included: small brown necrotic spots and veinal necrosis on primary leaves; necrosis on primary leaf petioles; interveinal chlorosis, with or without brown necrotic spots, on trifoliate leaves; and brown necrotic spots on stipules.”
Claim · model-written summary
Low Mn caused necrosis on primary leaf petioles.
- Taxon
- bush beant0
- Treatment
- low levels of Mn (0.1 ppm and above)e0
- Outcome
- necrosis on primary leaf petiolese0
Not reportedComparatorDirection
Verbatim
t0“bush bean”
e0“Toxicity symptoms, induced by low levels of Mn (0.1 ppm and above), included: small brown necrotic spots and veinal necrosis on primary leaves; necrosis on primary leaf petioles; interveinal chlorosis, with or without brown necrotic spots, on trifoliate leaves; and brown necrotic spots on stipules.”
Claim · model-written summary
Low Mn caused interveinal chlorosis, with or without brown necrotic spots, on trifoliate leaves.
- Taxon
- bush beant0
- Treatment
- low levels of Mn (0.1 ppm and above)e0
- Outcome
- interveinal chlorosis, with or without brown necrotic spots, on trifoliate leavese0
Not reportedComparatorDirection
Verbatim
t0“bush bean”
e0“Toxicity symptoms, induced by low levels of Mn (0.1 ppm and above), included: small brown necrotic spots and veinal necrosis on primary leaves; necrosis on primary leaf petioles; interveinal chlorosis, with or without brown necrotic spots, on trifoliate leaves; and brown necrotic spots on stipules.”
Claim · model-written summary
Low Mn caused brown necrotic spots on stipules.
- Taxon
- bush beant0
- Treatment
- low levels of Mn (0.1 ppm and above)e0
- Outcome
- brown necrotic spots on stipulese0
Not reportedComparatorDirection
Verbatim
t0“bush bean”
e0“Toxicity symptoms, induced by low levels of Mn (0.1 ppm and above), included: small brown necrotic spots and veinal necrosis on primary leaves; necrosis on primary leaf petioles; interveinal chlorosis, with or without brown necrotic spots, on trifoliate leaves; and brown necrotic spots on stipules.”
Claim · model-written summary
Increasing solution Fe alleviated or prevented Mn toxicity symptoms.
- Taxon
- bush beant0
- Treatment
- increasing Fe concentratione0
- Outcome
- Manganese toxicity symptomse0
- Direction
- alleviated or preventede0
Not reportedComparator
Verbatim
t0“bush bean”
e0“Manganese toxicity symptoms were alleviated or prevented by increasing Fe concentration in the nutrient solution.”
Claim · model-written summary
Leaf Mn increased with solution Mn.
Verbatim
t0“bush bean”
e0“Manganese concentration in the leaves increased with increasing Mn and decreased with increasing Fe concentration in the nutrient solution”
Claim · model-written summary
Leaf Mn decreased with solution Fe.
Verbatim
t0“bush bean”
e0“Manganese concentration in the leaves increased with increasing Mn and decreased with increasing Fe concentration in the nutrient solution”
Claim · model-written summary
Root Fe increased with solution Fe.
Verbatim
t0“bush bean”
e0“Iron concentration in the roots increased with increasing Fe concentration in the nutrient solution”
Claim · model-written summary
Leaf Fe was not significantly affected by increasing solution Mn.
Verbatim
t0“bush bean”
e0“Fe concentration in the leaves was not significantly affected by increasing Mn concentration in the solution culture.”
Claim · model-written summary
Mn toxicity symptoms developed at about 120 ppm leaf Mn.
Verbatim
t0“bush bean”
e0“Manganese toxicity symptoms developed when Mn concentration in the leaves reached about 120 ppm.”
Claim · model-written summary
A lower solution Fe/Mn ratio was associated with a proportionately lower leaf ratio.
Verbatim
t0“bush bean”
e0“A decrease in the Fe/Mn ratio in the nutrient solution resulted in a proportionate decrease in that of the leaves.”
Claim · model-written summary
Mn toxicity symptoms occurred at solution Fe/Mn ratio 10.0 or less.
Verbatim
t0“bush bean”
e0“Manganese toxicity symptoms occurred when the Fe/Mn ratio in the solution was 10.0 and below”
Claim · model-written summary
Mn toxicity symptoms occurred below leaf Fe/Mn ratio 1.5.
Verbatim
t0“bush bean”
e0“Manganese toxicity symptoms occurred when the Fe/Mn ratio in the solution was 10.0 and below, or when the ratio in the leaves was less than 1.5.”
Claim · model-written summary
Optimum growth without Mn toxicity required a solution Fe/Mn ratio of 20.0 to 25.0.
Verbatim
t0“bush bean”
e0“The ratio of Fe/Mn in the solution required for optimum growth of ‘Wonder Crop No. 2’ bean, without Mn toxicity symptoms, was in the range of 20.0 to 25.0.”
Claim · model-written summary
Authors attribute Mn-induced leaf chlorosis to excess Mn accumulation rather than Fe deficiency.
Verbatim
t0“bush bean”
e0“Results indicate that the chlorosis on bush bean leaves induced by excessive Mn in the nutrient solution was due to excessive accumulation of Mn and not to Fe deficiency.”
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manganese atom · disease · Phaseolus vulgaris (common bean)Positive and negative results
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2 papers in the same direction as this paper
- negative
- negative
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.