(23) THE EFFECT OF ‘SOAR’ BIOSTIMULANTS ON FRUIT YIELD OF BELL PEPPERS IN CONSECUTIVE SEASONS Alexander A. Csizinszky1 1

University of Florida/IFAS, Gulf Coast Research and Education Center, 14625 CR 672, Wimauma FL 33598, [email protected]

ABSTRACT Seaweed-based ‘SOAR’ biostimulants, ‘Micro Mix’ and ‘Bloom Spray’ were applied at two rates, 4.68L/ha and 7.02L/ha on bell pepper cultivars ‘Wizard X3R’ in Spring 2004 and Fall 2005, and on ‘Aristotle’ in Spring and Fall 2006, and Fall 2007, in replicated trials to investigate the effect of biostimulant effects on fruit yield and fruit size. The trials were conducted in westcentral Florida on light sandy soils. Production system was the conventional full-bed polyethylene mulch with seepage-(modified furrow-) irrigation in Spring 2004, Fall 2005 and Spring 2006, and micro- (drip-) irrigations in Fall 2006 and Fall 2007. In every season, yield of U.S. Fancy grade fruit was higher with ‘SOAR’ than with control treatment. The higher yields were due to a larger number of U.S. Fancy grade fruit rather than heavier weight per fruit. INTRODUCTION Bell pepper is the second most important vegetable crop in Florida. In 2005-2006, peppers were harvested from 6,677 ha (Fla. Agric. Stat. Directory 2007). Production was 14.45 million, 12.71 kg cartons for the value of U$187.33 million. Pepper growers, in average years, received higher prices for their product early in the season and also for U.S. Fancy grade fruit throughout the season. The application of biostimulants to vegetables claimed to increase earliness, fruit set and fruit size. In previous studies in west-central Florida, the effect of biostimulants on fruit size and yield depended on the cultivar (Csizinszky 1989, 2002). In this report, the results of studies conducted during several seasons to evaluate the yield response of bell peppers to foliar-applied ‘SOAR’. MATERIALS AND METHODS The studies in Spring 2004 were conducted on Eau Gallie fine sand (USDA 1983) and in the Fall 2005, Spring and Fall 2006, and Fall 2007, on Myakka fine sand (USDA 1989). The production system in all studies was the conventional full-bed polyethylene mulch (Geraldson et al., 1965) with seepage- (modified furrow-) irrigation in Spring 2004, Fall 2005 and Spring 2006, and micro- (drip-) irrigation in Fall 2006 and 2007. Treatments, ‘SOAR Micro Mix’ and ‘SOAR Bloom Spray’ (Chemical Dynamics, Inc. Plant City, FL) (Table 1) at two rates, 4.68L/ha (T2)

Table 1. Partial composition of ‘SOAR’ biostimulant products applied on bell peppers cultivars. Elements (%) Biostimulant

Ca

Mg

B

Cu

Fe

Mn

Mo

Zn

Micronutrient Mix

0.0

1.5

0.5

0.01

3.0

0.6

0.01

0.5

Seaweed(Ascophylum nodosum) base and humic (0.5%) and fulvic (0.2%) acids Bloom Spray

4.0

1.0

1.0

---

---

---

0.02

---

Seaweed(Ascophylum nodosum) base and humic (0.5%) and fulvic (0.2%) acids and 7.02L/ha (T3) and a control (T1) were arranged in a randomized complete block experimental design with four replications. The land was prepared on 10 February in 2004, 5 August in 2005, 7 February and 27 July in 2006, and 25 July in 2007. Raised beds, 23-cm high and 81-cm wide were spaced on 1.53-m centers. With the seepage irrigation production in Spring 2004 and Fall 2005, nutrients, applied at land preparation, were (in kg/ha) 269N, 43P, and 337K, and in Fall 2005 337N, 48P and 516K. Soil was fumigated with Terr-O-Gas 67 (66.6% methyl bromide and 33.3% chloropicrin) at 239 kg/ha in Spring 2004 and Fall 2005, and 196 kg/ha in Spring 2006. The beds in the spring seasons were covered with black and in the fall with white polyethylene film. With the micro-irrigated production in Fall 2006, 339N, 169P and 367K and in the Fall 2007 116N, 23 P and 181K (kg/ha) were applied for the crop during the season. Soil in both years was fumigated with Terr-O-Gas at 196 kg/ha, then beds were covered with ‘Canslit’ Full Metallic Mulch. On 26 February 2004 and 30 August 2005, five-week old ‘Wizard X3R’ seedlings, and on 13 March and 11 August in 2006 and 31 August in 2007 ‘Aristotle’ seedlings were transplanted in double rows at 30.5-cm between- and 36-cm withinrow spacing in the 4.32-m long plots (24 plants/plot). The seedlings of both pepper cultivars were raised in 2.54-cm cell sized planter flats by a commercial company. In all five studies the ‘SOAR’ biostimulants at both the 4.68L/ha and 7.02L/ha rates in 935 liters of water, were applied as follows: two weeks after transplanting ‘Micronutrient Mix’, then ‘Bloom Spray’ at first bloom, followed by two ‘Micronutrient Mix’ applications at two week intervals, then two weeks after the last ‘Micronutrient Mix’ application ‘Bloom Spray’ at the 4.68L/ha rate only. The biostimulants were applied by backpack sprayer with a hollow-cone nozzle at 2.81 kg/cm2 pressure. During the season, insecticides and fungicides, registered for bell peppers, were applied on a preventative weekly basis. Fruits were harvested four times in Spring 2004, and five times in Fall 2007. Fruits were separated into marketable and cull, then marketable fruits were graded as U.S. Fancy, U.S. No. 1, U.S. No. 2 (USDA, 1981), counted and weighed. Yield data were analyzed by the analysis of variance (ANOVA) statistical method. RESULTS AND DISCUSSION In Spring 2004, early yield of U.S. Fancy grade fruit of ‘Wizard X3R’ was higher with 4.68L/ha ‘SOAR’ than with 7.02L/ha ‘SOAR’ or control (Table 2). The yields of U.S. No. 1 and

U.S. No. 2 grade fruits were higher with control than 4.68L/ha ‘SOAR’. Marketable yields were similar with all treatments. Cull fruit yield was highest with the 7.02L/ha ‘SOAR’. For the season, U.S. Fancy fruit yield was higher with 4.68L/ha ‘SOAR’ than with control or 7.02L/ha ‘SOAR’. Yields of U.S. No. 1, U.S. No. 2, and marketable total were similar with ‘SOAR’ or control treatments. Yield of cull fruit was lower with 4.68L/ha ‘SOAR’ than with control. In Fall 2005, U.S. Fancy grade yield of ‘Wizard X3R’ in the early harvest was higher with 7.02L/ha ‘SOAR’ than with control. Yield of U.S. No. 1 fruit was higher with control than with ‘SOAR’ treatments. The U.S. No. 2 and marketable total yields were similar with all treatments. Cull fruit yields were higher with control and 4.68L/ha ‘SOAR’ than with 7.02L/ha ‘SOAR’. For the season, yields of U.S. Fancy, No. 2, and marketable total fruits were higher with 7.02L/ha ‘SOAR’ than with control. Yield of cull fruit was lower with 7.02L/ha ‘SOAR’ than with 4.68L/ha ‘SOAR’ or control. Yield of U.S. No. 1 fruit was similar with all treatments. In Spring 2006, early yields of U.S. Fancy, No. 1, No. 2 and marketable total fruit of ‘Aristotle’ pepper were higher with 7.02L/ha ‘SOAR’ than with control (Table 2). With 4.68L/ha ‘SOAR’ yields of U.S. Fancy and No. 2 fruits were higher, and U.S. No. 1 fruit yields was lower than with control. Yield of cull fruit was lower with ‘SOAR’ treatments than with control. For the season, U.S. Fancy and marketable total fruit yields were higher with the 4.68L/ha than with 7.02L/ha ‘SOAR’. Seasons’ total yields of No. 1, No. 2 and cull fruits were similar with ‘SOAR’ or control treatment. In Fall 2006, in the early harvest, U.S. Fancy yield of ‘Aristotle’ pepper was higher with 7.02L/ha ‘SOAR’ than with 4.68L/ha ‘SOAR’ or control. Yield of No. 1, No. 2, and marketable total fruits, however, were higher with 4.68L/ha ‘SOAR’ than with 7.02L/ha ‘SOAR’ or control. Yield of cull fruit was similar with all treatments. For the season, fruit yields for each grade and for marketable total were higher with 4.68L/ha ‘SOAR’ than with control. With 7.02L/ha ‘SOAR’, yields of U.S. Fancy and marketable total fruits were similar, but No. 1 and No. 2 grade fruit yields were similar, but No. 1 and No. grade fruits were lower than with 4.68L/ha ‘SOAR’. Yield of cull fruit was lower with 4.68L/ha ‘SOAR’ than with 7.02L/ha ‘SOAR’ or control. In Fall 2007, early yield of U.S. Fancy fruit of ‘Aristotle’ pepper was higher with both ‘SOAR’ treatments than with control. Yield of No. 1 fruit was higher with control and 4.68L/ha ‘SOAR’ than with 7.02L/ha ‘SOAR’, and No. 2 fruit yield was higher with control than with ‘SOAR’ treatments. Marketable total fruit yields were similar with all treatments. Cull fruit yield was higher with 4.68L/ha ‘SOAR’ than control, however, no cull fruit was recorded with 7.02L/ha ‘SOAR’. Seasonal total yield of U.S. Fancy fruit was higher with the ‘SOAR’ treatments than with control. Yield of U.S. 1 fruit was higher with 7.02L/ha than with 4.68L/ha ‘SOAR’ and the No. 2 fruit yield with control was higher than with ‘SOAR’ treatments. Marketable total fruit yield were similar with all treatments. Yield of cull fruit was higher with control than with ‘SOAR’ treatments. In the 5 trials, number of fruits harvested have shown similar trends to the weight of fruit yields for both pepper cultivars (Table 3). Weight per fruit for the same grade was not significantly different with ‘SOAR’ or with control treatment (Table 4).

Table 2. Fruit yield (t/ha) of ‘SOAR’ biostimulant-treated bell peppers. Fruit size Year Cultivar Season Treatmen Fancy No. 1 No. 2 Spring t/hab 2004 Wizard

earlyc

Season’s total of 4 harvests

2005 Wizard

Fall earlyc

Season’s total of 3 harvests

2006 Aristotle

Spring early a

Season’s total of 3 harvests

2006 Aristotle

Fall earlyc

Season’s total of 3 harvests

2007 Aristotle

Fall early

Marketable

Cull

1 2 3 1 2 3

1.41 cd 2.86 a 2.04 b 6.42 b 9.93 a 7.08 b

1.63 a 1.19 b 1.44 ab 23.57 a 22.91 a 22.28 a

0.63 a 0.13 b 0.69 a 7.08 a 7.43 a 7.40 a

3.67 a 4.18 a 4.17 a 37.07 a 40.27 a 36.76 a

0.53 b 0.63 b 1.16 a 10.75 a 9.03 b 10.53

1 2 3 1 2 3

3.38 b 3.82 ab 3.95 a 8.40 b 9.75 ab 10.84 a

4.20 a 2.63 b 2.66 b 11.34 a 10.69 a 12.25 a

0.88 a 0.78 a 0.88 a 1.94 b 3.32 a 3.00 a

8.46 a 7.24 a 7.49 a 21.68 b 23.76 ab 26.09 a

0.56 a 0.53 a 0.44 b 1.16 b 1.54 a 0.81 c

1 2 3 1 2 3

3.57 b 4.81 a 4.65 a 7.51 b 10.12 a 8.05 b

1.37 b 0.89 c 1.91 a 6.42 a 6.61 a 7.15 a

0.29 c 0.51 b 0.71 a 2.11 a 2.11 a 2.01 a

5.23 b 6.21 ab 7.26 a 16.04 b 18.84 a 17.21 ab

0.70 a 0.42 b 0.51 b 1.82 a 1.66 a 1.60 a

1 2 3 1 2 3

3.64 b 3.79 b 4.58 a 21.87 b 26.01 a 25.40 ab

2.01 b 3.42 a 1.94 b 14.73 b 18.21 a 13.54 b

0.44 b 1.32 a 0.56 b 2.85 b 4.11 a 2.32 b

6.09 b 8.53 a 7.08 b 39.45 b 48.33 a 41.26 ab

0.60 a 0.69 a 0.78 a 4.32 a 3.26 b 4.14 a

1 3.36 b 2.32 a 0.60 3 6.28 a 0.03 b 2 4.30 a 2.23 a 0.25 b 6.78 a 0.09 a 3 4.33 a 1.82 b 0.35 b 6.50 a 0.0 Season’s total of 5 harvests 1 11.36 b 14.72 6.94 a 33.02 a 9.26 a 2 15.25 a 13.37 b 3.64 c 32.26 a 6.62 b 3 14.56 a 16.38 a 4.77 b 35.71 a 7.44 b a Treatment: 1 = control; 2 = ‘SOAR’ at 4.68L/ha; 3 = ‘SOAR’ at 7.02L/ha. b Hectare: 6,557 linear meters of mulched bed; 37,928 plants. c Early: first harvest d Means within column followed by the same letter are not significantly different (P≤0.05).

Table 3. Number of fruit per hectare of bell peppers treated with ‘SOAR’ biostimulants. Fruit size Year Cultivar Season Treatment Fancy No. 1 No. 2 Marketable Spring no/ha (x 1000)b 2004 Wizard earlyc 1 6.45cd 9.19 a 4.15 a 19.79 a 2 12.87 a 7.36 b 0.91 b 21.14 a 3 9.19 b 9.19 a 4.15 a 22.53 a Season’s total of 4 1 27.60 b 134.40 a 47.42 a 209.42 a harvests 2 43.74 a 134.40 a 52.01 a 230.15 a 3 31.75 b 131.65 a 50.19 a 213.59 a Fall 2005 Wizard early 1 19.28 a 35.88 a 7.64 a 62.80 a 2 20.63 a 21.08 b 5.83 b 47.54 b 3 22.44 a 20.63 b 6.72 ab 49.79 b Season’s total of 3 1 47.07 b 91.06 a 19.74 b 157.87 b harvests 2 58.76 ab 85.67 a 30.96 a 175.39 ab 3 65.51 a 98.67 a 28.24 a 192.42 a 2006

Aristotle

Spring

Season’s total of 3 harvests

2006

Fall Aristotle early

Season’s total of 3 harvests

200

Aristotle

Fall early

Cull 2.77 c 4.60 b 7.81 a 76.90 ab 67.71 b 81.94 a 3.58 a 3.14 a 3.14 a 8.97 b 12.55 a 7.19 b

1 2 3 1 2 3

15.81 b 20.26 a 20.48 a 33.23 b 43.98 a 35.26 b

8.92 b 5.88 c 12.36 a 39.54 a 40.55 a 42.60 a

1.63 c 2.84 b 3.63 a 15.00 a 14.38 12.36 b

26.36 b 28.98 b 36.47 a 87.77 a 98.91 a 90.22 a

3.63 a 2.64 b 3.85 a 11.54 a 13.20 a 12.16 a

1 2 3 1 2 3

21.10 b 22.36 ab 27.72 a 125.85 b 147.77 a 151.89 a

16.98 b 28.14 a 16.56 b 115.07 b 140.72 a 107.19 b

3.31 b 14.90 a 4.15 b 26.91 b 43.04 a 22.36 b

41.39 b 65.40 a 48.13 b 267.83 b 331.53 a 281.45 ab

8.28 b 12.01 a 12.82 a 47.62 a 44.73 a 49.25 a

1 19.87 b 15.74 a 3.73 a 39.34 a 0.42 b 2 24.41 ab 16.98 a 2.06 b 43.45 a 0.84 a 3 25.25 a 12.82 b 2.50 b 40.57 a 0.0. Season’s total of 5 1 67.04 b 112.63 60.44 a 235.11 a 76.21 a harvests 2 89.47 a 105.88 b 43.66 b 229.31 a 51.20 b 3 90.24 a 124.83 a 52.90 258.49 a 63.83 ab a Treatment: 1 = control; 2 = ‘SOAR’ at 4.68L/ha; 3 = ‘SOAR’ at 7.02L/ha. b Hectare: 6,557 linear meters of mulched bed; 37,928 plants. c Early: first harvest d Means within column followed by the same letter are not significantly different (P≤0.05).

Table 4. Weight per fruit (g) of ‘SOAR’ biostimulant-treated bell peppers. Fruit size a Year Cultivar Season Treatment Fancy No. 1 No. 2 Marketable Spring g/fruit b 2004 Wizard early 1 219 177 151 185 2 222 162 137 197 3 222 158 166 185 Season’s total of 4 harvests 1 233 175 150 177 2 227 171 143 175 3 223 170 148 172 Fall 2005 Wizard earlyb 1 176 161 115 135 2 186 125 135 163 3 176 129 131 151 Season’s total of 3 harvests 1 179 125 99 137 2 166 125 107 136 3 166 124 107 146 Spring 2006 Aristotle early b 1 222 151 173 195 2 234 149 177 211 3 224 153 190 196 Season’s total of 3 harvests 1 222 160 138 179 2 226 160 144 187 3 224 165 160 187

2006 Aristotle

Fall earlyb

Season’s total of 3 harvests

2007 Aristotle

Fall earlyb

1 2 3 1 2 3

173 170 165 174 176 168

118 122 118 131 130 126

133 88 136 106 96 102

1 169 147 161 2 176 131 121 3 171 142 140 Season’s total of 5 harvests 1 169 131 115 2 170 126 83 3 161 131 90 a Treatment: 1 = control; 2 = ‘SOAR’ at 4.68L/ha; 3 = ‘SOAR’ at 7.02L/ha. b Early: first harvest

Cull 193 137 149 140 134 129 158 170 140 130 122 113 190 154 130 155 124 129

147 130 147 147 146 147

72 56 61 91 73 84

160 156 160 140 141 138

71 71 0 122 129 117

CONCLUSIONS The application of ‘SOAR’ biostimulants on bell peppers in the 5 studies described in this paper, resulted in a higher yield of U.S. Fancy grade fruit in every trial, and a higher seasonal total marketable fruit yield in 3 of the 5 trials. In our previous studies on the effect of biostimulants on bell pepper yields, the results varied with cultivar and with season (Csizinszky, 1989; 2002). In these studies, the foliar-applied ‘SOAR’ seaweed-based biostimulants that also contain humic and fulvic acids that are known to help the absorption of minerals by plants (Beames, 1986), significantly increased the yield of the large size fruit, compared to control. The yield increase in the U.S. Fancy grade fruit with the ‘SOAR’ treatment was especially great in the early harvest, when the growers usually received a higher price for their produce than later in the season. Therefore, the application of ‘SOAR Micronutrient Mix’ and ‘SOAR Bloom Spray’ is an economical method for the growers to increase bell pepper yields and receive a higher return on their investment for producing the crop. LITERATURE CITED Beames, G.H. 1986. Use of humic substances as agricultural plant biostimulants. Rocky Mountain Regional Meeting, American Chemical Society. 17 p. Csizinszky, A.A. 1989. Response of two bell pepper (Capsicum annuum L.) cultivars to foliarand soil-applied biostimulants. Soil and Crop Sci. Soc. Fla. Proc. 49:199-203. Csizinszky, A.A. 2002. Differential yield response of bell pepper cultivars to biostimulant treatments. University of Florida, IFAS, EDIS, http://edis.ifas.ufl.edu. HS125. Csizinszky, A.A. 2005a. Yield response of ‘Wizard X3R’ bell pepper to foliar-applied SOAR biostimulant in west-central Florida. GCREC Research Report BALM-2005-2. Csizinszky, A.A. 2006a. Evaluation of ‘SOAR’ biostimulant on the fruit yield of ‘Wizard X3R’ bell pepper. GCREC, Wimauma, http://gcrec.ifas.ufl.edu. Csizinszky, A.A. 2006b. Yield response of ‘Aristotle’ bell pepper to foliar-applied ‘SOAR’ biostimulants. http://gcrec.ifas.ufl.edu. Csizinszky, A.A. 2007. Evaluation of ‘SOAR’ biostimulants on the fruit yield of ‘Aristotle’ bell pepper. http://gcrec.ifas.ufl.edu. Csizinszky, A.A. 2008. Yield response of ‘Aristotle’ bell pepper to foliar-applied ‘SOAR’ biostimulants. http://gcrec.ifas.ufl.edu. Florida Agriculture Statistical Directory 2007. Fla. Dept. of Agriculture and Consumer Services, Tallahassee, FL. www.nass.usda.gov/fl. Geraldson, C.M., A.J. Overman, and J.P Jones. 1965. Combination of high analysis fertilizer, plastic mulch, and fumigation for tomato production on old agricultural land. Proc. Soil and Crop Sci. Soc. Fla. 28:18-24. United States Department of Agriculture. 1963. United States Standards for grades of sweet peppers. USDA Agr. Mktg. Service, Washington, DC. United States Department of Agriculture. 1989. Soil survey of Manatee County, Florida. USDA Soil Conservation Service, Washington, DC. United States Department of Agriculture. 1989. Soil survey of Hillsborough County, Florida. USDA Soil Conservation Service, Washington, DC.