EFFECT OF K RATE AND SOURCE ON TOMATO YIELDS

Experiments were conducted in the spring of 1990 at Quincy and Live Oak, Florida and 1991 in Quincy to study the effect of 3 K sources (KCl, K2SO4 and KNO3) and 5 K rates (0, 75, 150, 225 and 300 kg ha-1) of yield of `Sunny' tomatoes. Preplant soil test K values were 37 and 54 ppm in 1990, respectively, and 44 ppm in 1991. These K concentrations are considered medium (36-60) for Florida mineral soils. K source had no effect on yield, fruit weight or percent marketable fruit in all studies. In 1990, total yields, yield of extra large (> 7.0 cm) fruit and percent marketable fruit were increased with application of 75 kg ha-1 of K but there was no further response to applied K at both locations. In 1991, total yield increased with applied K up to 150 kg ha-1 then decreased. Fruit size and percent marketable fruit increase with 75 kg ha-1 of K but no further response occurred. There was no interaction of K source and K rate.

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Temperature Has a Greater Effect on Fruit Growth than Defoliation or Fruit Thinning in Strawberries in the Subtropics

Agriculture ◽

10.3390/agriculture9060127 ◽

2019 ◽

Vol 9 (6) ◽

pp. 127

Author(s):

Christopher M. Menzel

Keyword(s):

Opposite Effect ◽

Fruit Size ◽

Fruit Weight ◽

Fruit Growth ◽

Effect Of Temperature ◽

Fragaria Ananassa ◽

Fruit Thinning ◽

Mature Leaves ◽

Small Fruit ◽

Marketable Fruit

Fruit size declines in strawberries (Fragaria × ananassa Duch.) as the season progresses in many subtropical areas, possibly due to inadequate leaf area, over-cropping, or high temperatures. An experiment was conducted to investigate the importance of these factors on fruit growth in ‘Festival’ in Queensland, Australia. Groups of plants were defoliated to remove half of the mature leaves on each plant, thinned to remove all the inflorescences on each plant, or defoliated and thinned. Control plants were left intact. Defoliation, thinning, or defoliation + thinning decreased yield (total and/or marketable) by 15% to 24% compared with the control. Defoliation, or defoliation + thinning decreased average fruit weight (total and/or marketable fruit) by 1 to 2 g compared with the control, whereas thinning had the opposite effect. The incidence of small fruit increased towards the end of the season. There were strong relationships between fruit weight and average daily mean temperature in the seven weeks before harvest (R2s greater than 0.80). Fruit weight decreased from 24 g to 8 g as the temperature increased from 16 °C to 20 °C. This response was not affected by defoliation or thinning. The strong effect of temperature on fruit size indicates a problem for production in the future in the absence of heat-tolerant cultivars.

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537 PB 043 ROWCOVER AND BLACK PLASTIC MULCH EFFECTS ON TOMATO PRODUCTIONS

HortScience ◽

10.21273/hortsci.29.5.508d ◽

1994 ◽

Vol 29 (5) ◽

pp. 508d-508

Author(s):

Ibrahim G. Rubeiz ◽

Marlene M. Freiwat

Keyword(s):

Air Temperature ◽

Total Yield ◽

Fruit Size ◽

Plastic Mulch ◽

Fruit Setting ◽

Negative Effect ◽

Black Plastic ◽

Effect On Yield ◽

Yield Time ◽

And Control

Tomato cv. Alwadi were grown under floating rowcover, black plastic mulch, mulch plus rowcover, or no protection i.e. control, for studying the effect on yield in terms of earliness, total yield and average fruit size. Early yield was significantly increased by the mulch treatment while the rowcover treatment yielded the least (P < 0.05). Total yield was increased by the mulch and mulch plus rowcover treatments, while the rowover and control treatments yielded the least (P < 0.05). Soil temperature at 10 cm depth varied between 1° to 2°C only under the different treatments. Air temperature under the rowcover exceeded 35 to 40°C on many days, hence causing fruit setting problems and resulting in reduced early yield under the rowcover. Our results show that earliness is enhanced by black plastic mulch, while the rowcover alone can have a negative effect on yield. Time of rowcover removal above the mulch warrants further research.

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Effect on Yield and Quality of a Simple System to Recycle Nutrient Solution to Greenhouse Tomato

HortScience ◽

10.21273/hortsci.47.11.1641 ◽

2012 ◽

Vol 47 (11) ◽

pp. 1641-1645 ◽

Cited By ~ 3

Author(s):

Martin P.N. Gent ◽

Michael R. Short

Keyword(s):

Nutrient Solution ◽

Root Zone ◽

Total Yield ◽

Fruit Size ◽

Vegetable Production ◽

Marketable Yield ◽

Greenhouse Tomato ◽

Growth Product ◽

Effect On Yield ◽

Dietary Value

Recycling the nutrient solution used for greenhouse vegetable production can prevent groundwater pollution. Recycling could result in an accumulation or deficiency of elements that would be deleterious to plant growth, product quality, and the dietary value of vegetables. Complex fertilizer systems have been developed to maintain appropriate concentrations of all elements in recycled systems. We compared a much simpler system in which all excess solution drained from the plants was recycled without adjustment or dilution compared with a system with no recycling as a control. Crops of greenhouse tomato (Solanum lycopersicon L.) were grown in two years to compare these systems. Differences in composition of solution drained from the plants developed gradually over more than one month. The transition from vegetative to fruit growth, which coincided with warmer weather, resulted in a decreased demand for nitrate, and other nutrients, and an increase in electrical conductivity (EC) of water drained from the root zone. The composition of the fresh solution supplied to the plants was adjusted accordingly. It took a longer time to re-establish an optimum composition for recycled compared with control watering. EC tended to increase in the recycled system. Recycling decreased total yield and fruit size, but marketable yield was unaffected. The marketable fraction increased in the recycled treatment, primarily as a result of fewer fruit with cracked skin. This effect was consistent across seven cultivars. The cultivars differed in this and other defects, but they did not differ in their response to the two watering systems.

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Black Polyethylene Mulch Doubled Yield of Fresh-market Field Tomatoes

HortScience ◽

10.21273/hortsci.27.7.787 ◽

1992 ◽

Vol 27 (7) ◽

pp. 787-789 ◽

Cited By ~ 16

Author(s):

Aref Abdul-Baki ◽

C. Spence ◽

R. Hoover

Keyword(s):

Field Experiments ◽

Total Yield ◽

Fruit Size ◽

Fruit Weight ◽

Planting Date ◽

Trickle Irrigation ◽

Fresh Market ◽

Planting Dates ◽

Early Production ◽

Polyethylene Mulch

Field experiments were conducted to a) maximize total yield of fresh-market field tomato (Lycopersicon esculentum Mill.) cultivars using black polyethylene mulch (BPM), and b) increase fruit size and yield during the last 5 weeks of the production period by reducing the number of synthate sinks per plant through eliminating all flowers that appeared during this period. Unmulched treatments under trickle irrigation and multiple applications of soluble fertilizer yielded an average of 43 t·ha-1 for `Sunny' and `Pik-Rite' over the two planting dates. With BPM, total yield increased by 95% to 84 t·ha-1. Although total yield increases due to BPM over the control were highly significant in both cultivars and over the two planting dates, yield increases were higher for the early than for the optimum planting date. BPM also significantly increased early production of `Pik-Rite' but not `Sunny', and the increase in early production was more pronounced for the optimum than the early planting date. Sink reduction during the last 5 weeks of the growing season had no effect on yield or fruit weight during that period.

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Potassium Application and Leaf Sufficiency Level for Fresh-market Tomatoes Grown on a Midwestern United States Fine-textured Soil

HortTechnology ◽

10.21273/horttech.16.2.0247 ◽

2006 ◽

Vol 16 (2) ◽

pp. 247-252 ◽

Cited By ~ 2

Author(s):

H.G. Taber

Keyword(s):

Growth Habit ◽

Total Yield ◽

Fruit Size ◽

Size Difference ◽

Fresh Market ◽

Marketable Yield ◽

Leaf Petiole ◽

Indeterminate Growth Habit ◽

Loam Soil ◽

Marketable Fruit

Tomato (Lycopersicon esculentum) response to potassium (K) fertilization on a well-drained, central Iowa loam soil testing low in exchangeable K was evaluated over a 3-year period. Each year the experimental design was a factorial, split-plot randomized complete block with K rate as the whole unit (0 to 332 lb/acre). The subunit was cultivar, either `Mountain Spring' (determinate growth habit) or `Jet Star' (indeterminate growth habit). Fruit harvest began the first week of August and continued weekly for 5 to 8 weeks. For all years there was a significant K rate and cultivar effect for all parameters, but no interaction except for marketable fruit size and unmarketable fruit produced. Increasing the K rate to 103 lb/acre increased fruit size of both cultivars to a maximum of 8.9 oz, but year accounted for greater fruit size difference than the choice of cultivar. Maximum marketable yield for both cultivars occurred at 220 lb/acre K with `Jet Star' producing 13% more fruit than `Mountain Spring', 359 vs. 319 cwt/acre, respectively. Cullage was high, mostly as a result of blotchy ripening disorders, with `Jet Star' consistently producing more culls than `Mountain Spring'. Increasing K rate did not reduce the percentage of culls, which remained constant at about 29% of total yield. Whole-leaf K and leaf petiole sap K levels linearly increased with additional K rate for the two sample periods at flowering and mid-harvest. The whole-leaf K sufficiency level for both cultivars at the flowering stage of growth was determined to be 3.15% and dropped to 1.30% K by mid-harvest. Critical petiole leaf sap K values (using a dilution of 1:1 sap to water) could not be determined at flowering, but at mid-harvest the critical value was about 2200 to 2800 ppm K.

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Two Reproductive Bud Thinning Alternatives for Cactus Pear

HortTechnology ◽

10.21273/horttech.20.1.202 ◽

2010 ◽

Vol 20 (1) ◽

pp. 202-205 ◽

Cited By ~ 5

Author(s):

Jorge A. Zegbe ◽

Jaime Mena-Covarrubias

Keyword(s):

Fruit Size ◽

Growing Season ◽

Fruit Weight ◽

Export Markets ◽

Cactus Pear ◽

Opuntia Ficus Indica ◽

Fruit Crop ◽

Marketable Fruit

Cactus pear (Opuntia spp.) is an important Mexican fruit crop cultivated extensively (about 51,000 ha) in the semiarid highlands of Mexico. Fruit exports have increased in the last decade, but to fulfill these markets, fruit size must be enhanced. However, current hand thinning reduces yield, thus making it uneconomical for growers. The objective was to evaluate two reproductive bud (RB) thinning protocols in an effort to increase export fruit size without depressing cactus pear yield. Two experiments were conducted during the 2004 growing season with two cactus pear types: Cristalina (Opuntia albicarpa) and Rojo liso (Opuntia ficus-indica). In the first experiment, the treatments were no thinning (control) or keeping 4, 8, or 12 RBs per cladode. In the second experiment, the treatments were no thinning (control), thinning every other bud along the cladode, and thinning two of every three buds along the cladode. In the first experiment, yield of Cristalina was reduced by 10.4% and 51.8% when eight or four RBs per cladode were retained, respectively. Mean fruit weight of Cristalina decreased with the most severe thinning treatment. Yield of Rojo liso was reduced when four RBs were retained per cladode. In the second experiment, yield of both cactus pear types was unaffected by the thinning treatments. Therefore, we recommend thinning every other bud along the cladode because it does not reduce yield and tends to improve marketable fruit in both cactus pear types. However, this thinning alternative should be tested in other commercial cactus pear types if growers are interested in export markets.

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Weather Affects Seedless Watermelon Yield, But Not Fruit Size or Quality

HortScience ◽

10.21273/hortsci.39.4.748e ◽

2004 ◽

Vol 39 (4) ◽

pp. 748E-748 ◽

Cited By ~ 1

Author(s):

Timothy E. Elkner* ◽

David H. Johnson

Keyword(s):

Fruit Quality ◽

Total Yield ◽

Fruit Size ◽

Fruit Weight ◽

Soluble Solids ◽

Fruit Number ◽

Seedless Watermelon

Medium-sized triploid watermelons were evaluated in southeast Pennsylvania in 2002 and 2003 to determine the best adapted cultivars for this region. The 2002 season was unusually hot and dry, while 2003 was unusually cool and wet. Yields and fruit quality were compared for the eight cultivars that were grown both seasons to determine the effect of weather on seedless watermelon. Cooler temperatures reduced total fruit number and total yield but not average fruit weight or soluble solids. Researchers evaluating triploid watermelons over several seasons can compare size and °Brix among cultivars, but will need to be cautious when predicting total yields.

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Fertilizer Substitutions in Hydroponically Grown Greenhouse Tomatoes

HortTechnology ◽

10.21273/horttech.9.1.59 ◽

1999 ◽

Vol 9 (1) ◽

pp. 59-65 ◽

Cited By ~ 1

Author(s):

A.P. Papadopoulos ◽

S. Pararajasingham ◽

X. Hao

Keyword(s):

Fruit Quality ◽

Total Yield ◽

Growth Yield ◽

Fruit Weight ◽

Crop Growth ◽

Partial Substitution ◽

Marketable Yield ◽

Nutrient Film Technique ◽

Marketable Fruit ◽

Crop Growth Stage

Experiments were carried out to evaluate two salts, K2SO4 and NaCl, as materials to supplement the electrical conductivity (EC) of the basic nutrient solution in nutrient film technique (NFT). The effects of these materials on the growth, yield and fruit quality of greenhouse tomato (Lycopersicon esculentum Mill.) grown by NFT were quantified. These effects were tested by increasing the recirculating solution EC from a base value of 1500 μS·cm-1 to that suitable for the crop growth stage with normal feed (macronutrients), 0.38 m (0.53 lb/gal) K2SO4 or 1.14 m (0.55 lb/gal) NaCl, at a common pH of 6.2. In 1995 and 1996, there were no significant effects of the treatments on crop growth. In 1995, the early marketable yield was significantly lower when K2SO4 was used but the yield at the end of the season did not differ among the treatments. Furthermore, with K2SO4, the proportion of grade #1 fruit in early total yield was lower than in the control, while, fruit biomass content was higher than in the NaCl treatment. In 1996, the cumulative marketable fruit weight was unaffected by the treatments. A trend toward high number of large grade fruit occurred with the NaCl treatment. The pH and EC of the fruit homogenate were favorably affected by the NaCl treatment. Adding K2SO4 or NaCl in partial substitution of macronutrients in the recirculating solution may have a role in NFT systems in not only reducing environmental pollution (from nitrates and phosphates) and fertilizer costs, but also in improving fruit quality and, therefore, profit margins.

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Tree Growth, Fruit Size, and Yield Response of Mature Peach to Weed-Free Intervals

Weed Technology ◽

10.1614/wt-06-002.1 ◽

2007 ◽

Vol 21 (1) ◽

pp. 102-105 ◽

Cited By ~ 5

Author(s):

Andrew W. MacRae ◽

Wayne E. Mitchem ◽

David W. Monks ◽

Michael L. Parker ◽

Roger K. Galloway

Keyword(s):

North Carolina ◽

Total Yield ◽

Fruit Size ◽

Fruit Weight ◽

Yield Response ◽

Peach Tree ◽

Cross Sectional ◽

Common Lambsquarters ◽

Smooth Pigweed ◽

Large Crabgrass

An experiment was conducted at one location in 1999 and two locations in 2000 to determine the critical weed-free period for peach in North Carolina. The cultivars for the three locations were ‘Contender’, ‘Norman’, and ‘Summerprince’. Weed-free intervals of 0, 3, 6, 9, 12, and 15 wk after peach tree bloom were established. Paraquat at 1.1 kg ai/ha plus nonionic surfactant at 0.25% v/v was applied every 10 d, after treatments were initiated at peach bloom, to maintain weed-free plots. Large crabgrass, hairy vetch, and smooth crabgrass were the primary weeds in Contender. Horseweed, smooth crabgrass, and large crabgrass were the primary weeds in Norman. Bermudagrass, smooth pigweed, and common lambsquarters were the primary weeds in Summerprince. No differences in trunk cross-sectional area were observed between the weed-free periods. Maintaining the orchard floor weed-free for 12 wk after peach tree bloom resulted in the greatest fruit size (individual fruit weight and diameter), total yield, and fruit number.

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Effect of Bicyclopyrone on Triploid Watermelon in Plasticulture

Weed Technology ◽

10.1017/wet.2018.36 ◽

2018 ◽

Vol 32 (4) ◽

pp. 439-443 ◽

Cited By ~ 1

Author(s):

Matthew B. Bertucci ◽

Katherine M. Jennings ◽

David W. Monks ◽

David L. Jordan ◽

Jonathan R. Schultheis ◽

...

Keyword(s):

Weed Management ◽

Total Yield ◽

Fruit Size ◽

Field Studies ◽

Yield Response ◽

Marketable Yield ◽

Fruit Number ◽

Triploid Watermelon ◽

Marketable Fruit ◽

Polyethylene Mulch

AbstractField studies were conducted to determine watermelon tolerance and yield response when treated with bicyclopyrone preplant (PREPLANT), POST, and POST-directed (POST-DIR). Treatments consisted of two rates of bicyclopyrone (37.5 and 50 g ai ha–1), fomesafen (175 g ai ha–1), S-metolachlor (802 g ai ha–1), and a nontreated check. Preplant treatments were applied to formed beds 1 d prior to transplanting and included bicyclopyrone (37.5 and 50 g ha–1) and fomesafen (175 g ha–1), and new polyethylene mulch was subsequently laid above treated beds. POST and POST-DIR treatments were applied 14 ± 1 d after watermelon transplanting and included bicyclopyrone (37.5 and 50 g ha–1) POST and POST-DIR, and S-metolachlor (802 g ai ha–1) POST-DIR. POST-DIR treatments were applied to row middles, ensuring that no herbicide contacted watermelon vines or polyethylene mulch. At 2 wk after transplanting (WAT), 15% foliar bleaching was observed in watermelon treated with bicyclopyrone (50 g ha–1) PRE. At 3 WAT, bicyclopyrone (37.5 and 50 g ha–1) POST caused 16% and 17% foliar bleaching and 8% and 9% crop stunting, respectively. At 4 WAT, initial injury had subsided and bicyclopyrone (37.5 and 50 g ha–1) POST caused 4% and 4% foliar bleaching and 4% and 8% crop stunting, respectively. No symptoms of bleaching or stunting were observed at 6- and 8-WAT ratings. Watermelon total yield, marketable yield, total fruit number, marketable fruit number, and average fruit size were unaffected by herbicide treatments. Therefore, registration of bicyclopyrone (37.5 and 50 g ha–1) PREPLANT, POST, and POST-DIR would offer watermelon producers a safe herbicide option and a novel mode of action for weed management.

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