Abstract
Seaweed extract, fish emulsion, and soybean meal (SBM) are United States Department of Agriculture (USDA) National Organic Program (NOP) allowed substances used by organic vegetable growers as fertilizers. Soil applied SBM and foliar applied seaweed, fish, fish/seaweed, 20-20-20, and a water control were tested on field-grown sweet peppers, broccoli, and lettuce to determine their effects on plant nutrition and crop yield. The SBM was applied at three rates: 0, 2466, and 4932 kg.ha-1 (0, 2200, and 4400 lb.acre-1). To test the duration of the SBM as a soil fertilizer, peppers, broccoli, and lettuce were grown in succession on the same beds after the initial SBM application. The foliar fertilizers were also tested on peppers on a certified organic farm for comparison to the research station study. In 2002, transplanting one day after SBM application caused fertilizer burn to the pepper roots. In 2003, peppers were planted one week after SBM application without harm to plant roots. SBM positively increased the nutrient level and yield of broccoli in 2002 and peppers in 2003. Lettuce yield was not affected by the SBM treatments because the previous pepper and broccoli crops had likely exhausted the SBM fertilizer. The foliar sprays did not affect plant nutrient levels or yields in any crop at either location. Greenhouse studies were conducted to investigate the effect of SBM on germination and growth of eight common vegetables. Treatments included five rates of SBM: 0, 1093, 2186, 3279, and 4372 kg.ha-1 (0, 975, 1950, 2925, and 3900 lb.acre-1) and two application methods: surface applied (SA) and incorporated (IN) into the media. For all vegetables combined, at applications of 1093 and 2186 kg.ha-1 IN SBM, shoot weight increased by 20% and 10%, respectively, compared to the unfertilized control. At the same rate of SA SBM, shoot weight was reduced by 6% and 18% respectively. At all rates of SA SMB, shoot weight was more reduced in small seeded vegetables (spinach, lettuce, carrot, and radish) than in large seeded vegetables (squash, cucumber, bean, and pea). At 3279 and 4372 kg.ha-1 of IN SBM, shoot weight of small seeded vegetables was reduced by 8% and 46%, respectively. The EC and pH of the media increased with increased rates of SBM and were greater with SA SBM than with IN SBM. Levels above pH 6.5 and EC 1.0 dS.m-1 were measured on day 7 for media at all SBM rates. These levels could be inhibitory to germinating seeds. Because SBM reduced growth of small seeded vegetables, it is not recommended that small seeded vegetables be surface fertilized with SBM or that they be sown directly into soil where SBM has been recently incorporated. SBM incorporated at low rates (<2186 kg.ha-1) could prove to be a useful fertilizer for large seeded crops without concerns of inhibition by SBM. Field studies were conducted to investigate the optimal rate and timing of SBM fertilization in plasticulture sweet pepper production. SBM was applied at three rates: 0, 2421, and 4842 kg.ha-1 (0, 2165 and 4330 lb.acre-1). Sweet peppers were then transplanted at four intervals following SBM incorporation and black plastic application: one day, three days, seven days, and fourteen days. Growth was initially inhibited in peppers planted into the high rate of SBM less than one week after incorporation. By the end of the season, these peppers had recovered and had a biomass greater than the unfertilized control. Peppers fertilized with the low rate of SBM did not suffer an initial inhibition and had the highest yield of marketable peppers at all planting times. This study suggests a moderate rate of SBM should be applied at least two weeks before the intended planting date.
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Claims 20
Claim · model-written summary
Soybean meal increased nutrient level and yield of broccoli in 2002.
- Taxon
- broccoli
Brassica oleracea var. italicae0 - Treatment
- SBMe0
- Outcome
- nutrient level and yielde0
- Direction
- increasede0
- Qualifier
- 2002e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“SBM positively increased the nutrient level and yield of broccoli in 2002 and peppers in 2003”
Claim · model-written summary
Soybean meal increased nutrient level and yield of peppers in 2003.
CapsicumNot reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“SBM positively increased the nutrient level and yield of broccoli in 2002 and peppers in 2003”
Claim · model-written summary
Soybean meal treatments did not affect lettuce yield, which the authors attribute to earlier crops having exhausted the fertilizer.
- Taxon
- Lettuce
Lactuca sativae0 - Treatment
- SBM treatmentse0
- Outcome
- yielde0
- Direction
- not affectede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Lettuce yield was not affected by the SBM treatments because the previous pepper and broccoli crops had likely exhausted the SBM fertilizer”
Claim · model-written summary
Transplanting peppers one day after soybean meal application caused fertilizer burn to pepper roots in 2002.
- Taxon
- peppere0
- Treatment
- transplanting one day after SBM applicatione0
- Outcome
- fertilizer burne0
- Qualifier
- 2002e0
Not reportedComparatorDirection
Verbatim
e0“In 2002, transplanting one day after SBM application caused fertilizer burn to the pepper roots”
Claim · model-written summary
Peppers planted one week after soybean meal application were not harmed in 2003.
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In 2003, peppers were planted one week after SBM application without harm to plant roots”
Claim · model-written summary
Foliar sprays of seaweed, fish and fertilizer products did not affect plant nutrient levels or yields in sweet peppers, broccoli or lettuce.
- Taxon
- sweet peppers, broccoli, and lettuce
Capsicum annuumLactuca sativaBrassica oleracea var. italicae1 - Treatment
- foliar sprayse0
- Outcome
- plant nutrient levels or yieldse0
- Direction
- did not affecte0
- Comparator
- water controle1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The foliar sprays did not affect plant nutrient levels or yields in any crop at either location”
e1“Soil applied SBM and foliar applied seaweed, fish, fish/seaweed, 20-20-20, and a water control were tested on field-grown sweet peppers, broccoli, and lettuce”
Claim · model-written summary
Incorporated soybean meal at 1093 kg/ha increased shoot weight of vegetables by 20% relative to the unfertilized control.
Verbatim
e0“For all vegetables combined, at applications of 1093 and 2186 kg.ha-1 IN SBM, shoot weight increased by 20% and 10%, respectively, compared to the unfertilized control”
Claim · model-written summary
Incorporated soybean meal at 2186 kg/ha increased shoot weight of vegetables by 10% relative to the unfertilized control.
Verbatim
e0“For all vegetables combined, at applications of 1093 and 2186 kg.ha-1 IN SBM, shoot weight increased by 20% and 10%, respectively, compared to the unfertilized control”
Claim · model-written summary
Surface-applied soybean meal at 1093 kg/ha reduced shoot weight of vegetables by 6%.
Verbatim
e0“At the same rate of SA SBM, shoot weight was reduced by 6% and 18% respectively”
e1“For all vegetables combined, at applications of 1093 and 2186 kg.ha-1 IN SBM, shoot weight increased by 20% and 10%, respectively, compared to the unfertilized control”
Claim · model-written summary
Surface-applied soybean meal at 2186 kg/ha reduced shoot weight of vegetables by 18%.
Verbatim
e0“At the same rate of SA SBM, shoot weight was reduced by 6% and 18% respectively”
e1“For all vegetables combined, at applications of 1093 and 2186 kg.ha-1 IN SBM, shoot weight increased by 20% and 10%, respectively, compared to the unfertilized control”
Claim · model-written summary
Surface-applied soybean meal reduced shoot weight more in small seeded vegetables than in large seeded vegetables at all rates.
Verbatim
e0“At all rates of SA SMB, shoot weight was more reduced in small seeded vegetables (spinach, lettuce, carrot, and radish) than in large seeded vegetables (squash, cucumber, bean, and pea)”
Claim · model-written summary
Incorporated soybean meal at 3279 kg/ha reduced shoot weight of small seeded vegetables by 8%.
- Taxon
- small seeded vegetablese0
- Treatment
- IN SBMe0
- Outcome
- shoot weighte0
- Direction
- reducede0
- Value
- 8%e0
- Qualifier
- 3279e0
Not reportedComparator
Verbatim
e0“At 3279 and 4372 kg.ha-1 of IN SBM, shoot weight of small seeded vegetables was reduced by 8% and 46%, respectively”
Claim · model-written summary
Incorporated soybean meal at 4372 kg/ha reduced shoot weight of small seeded vegetables by 46%.
- Taxon
- small seeded vegetablese0
- Treatment
- IN SBMe0
- Outcome
- shoot weighte0
- Direction
- reducede0
- Value
- 46%e0
- Qualifier
- 4372e0
Not reportedComparator
Verbatim
e0“At 3279 and 4372 kg.ha-1 of IN SBM, shoot weight of small seeded vegetables was reduced by 8% and 46%, respectively”
Claim · model-written summary
EC and pH of the growing media increased with soybean meal rate and were greater with surface-applied than incorporated soybean meal.
- Treatment
- increased rates of SBMe0
- Outcome
- EC and pH of the mediae0
- Direction
- increasede0
- Qualifier
- Levels above pH 6.5 and EC 1.0 dS.m-1 were measured on day 7e1
- Comparator
- IN SBMe0
Not reportedTaxon
Verbatim
e0“The EC and pH of the media increased with increased rates of SBM and were greater with SA SBM than with IN SBM”
e1“Levels above pH 6.5 and EC 1.0 dS.m-1 were measured on day 7 for media at all SBM rates”
Claim · model-written summary
Small seeded vegetables should not be surface fertilized with SBM or sown directly into soil where SBM was recently incorporated.
Verbatim
e0“it is not recommended that small seeded vegetables be surface fertilized with SBM or that they be sown directly into soil where SBM has been recently incorporated”
Claim · model-written summary
Soybean meal incorporated at low rates could be a useful fertilizer for large seeded crops without inhibition.
Verbatim
e0“SBM incorporated at low rates (<2186 kg.ha-1) could prove to be a useful fertilizer for large seeded crops without concerns of inhibition by SBM”
Claim · model-written summary
Peppers planted into the high soybean meal rate less than one week after incorporation had initially inhibited growth.
- Treatment
- high rate of SBMe0
- Outcome
- Growthe0
- Direction
- inhibitede0
- Qualifier
- less than one week after incorporatione0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Growth was initially inhibited in peppers planted into the high rate of SBM less than one week after incorporation”
Claim · model-written summary
By the end of the season, peppers grown with the high soybean meal rate had a biomass greater than the unfertilized control.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“By the end of the season, these peppers had recovered and had a biomass greater than the unfertilized control”
e1“Growth was initially inhibited in peppers planted into the high rate of SBM less than one week after incorporation”
Claim · model-written summary
Peppers fertilized with the low soybean meal rate did not suffer an initial inhibition.
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Peppers fertilized with the low rate of SBM did not suffer an initial inhibition and had the highest yield of marketable peppers at all planting times”
Claim · model-written summary
Peppers fertilized with the low soybean meal rate had the highest yield of marketable peppers at all planting times.
- Treatment
- low rate of SBMe0
- Outcome
- yield of marketable pepperse0
- Direction
- higheste0
- Qualifier
- at all planting timese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Peppers fertilized with the low rate of SBM did not suffer an initial inhibition and had the highest yield of marketable peppers at all planting times”
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