Evaluation of 17 Specialty Pepper Cultivars in Southwest Michigan Ron Goldy Southwest Michigan Research and Extension Center Benton Harbor, Michigan Objective To evaluate the performance of 17 specialty pepper cultivars for adaptability to Southwest Michigan growing conditions. Summary Few statistical differences were noted for all traits measured in the three pepper types. Banana peppers had the greatest statistical differences and poblano the least. The four poblano types were similar in all traits except Masivo, which had a greater yield of cull fruit. Only Tornado had a significantly lower total yield among the jalapeno types. Average number one fruit weight was the variable trait of biggest interest in the banana types where TI 0198 and TI 0100 had a significantly higher fruit weight than the others. The 2013 trial was characterized by lower than average yield and higher than average culls due to cold temperatures experienced shortly after planting, cool temperatures early and late in the season, and hot temperatures in mid-july. Methods Fertilizer Prior to planting, nitrogen, potassium (K 2 O equivalent), sulfur, and boron were broadcast at 30, 150, 25, and 2 pounds per acre, respectively. After planting, nutrients were applied with Nitro Plus (18N-5Ca-1.5Mg and a proprietary growth regulator) at 15 gallons/acre on June 4, June 12, June 19, June 25, and July 3. 4-0-8 was applied at a rate of 7 pounds N/week on July 9, July 16, August 16, August 20, and August 27. Weed Control Weeds were controlled by black plastic on the beds. Between-row weeds were suppressed with Gramoxone using a backpack sprayer. Planting Plants were started in the greenhouse April 1 and planted to the field May 21. Plants were set on raised, black plastic mulched beds, 6 inches high, 22 inches wide at the top and 5.5 feet on center. Plants were set in double rows with 14 inches between rows and 18 inches in the row (10,560 plants/acre). The trial was planted and analyzed as a completely randomized design with 16 plants per plot and four replications. The three fruit categories (banana, jalapeno, and poblano) were analyzed separately. Plots were separated by four guard plants. Plant Care Plots were irrigated as needed and insects and diseases controlled using standard commercial practices.
Harvest and Data Collection Harvest was conducted August 13, August 29, and September 23, 2013. Fruit was graded into Number one, number two, and culls. Each category was weighed and converted into bushels per acre. Number one fruit was also counted and average number one fruit weight was determined. Results The 2013 growing season proved to be somewhat difficult for peppers. After planting on May 21 the plants experienced four nights of temperatures below 40 o F, with the lowest being 34.5 o F on May 25. These temperatures were recorded at the 5-foot level so temperatures at plant level were probably colder. Some damage to leaves and stems was observed. June and early July were also cooler than normal followed by six days above 90 o F in mid-july. The plants did not have the expected amount of early growth resulting in the decision to apply additional fertilizer prior to first fruit set. Additional fertilizer did not improve plant size as desired but did lead to development of dark green foliage. Cool temperatures also contributed to later first and final harvests and only three harvests. Cool temperatures followed by six days of high temperatures led to increased incidence of blossom end rot at the first harvest as indicated by the high number of culled fruit. Few statistical differences were found between the four poblano peppers in the trial (Table 1). They were similar in all traits measured except a greater number of cull fruit for Masivo. More differences were noted between the jalapeno entries (Table 2) but even they did not have many differences in the traits evaluated. Only one jalapeno ( Tornado ) had a significantly lower total yield. Tornado also had a significantly lower number one fruit weight compared to the others. Tornado and Jaguar were the only two jalapenos having significantly lower number one yield. The banana peppers did not have any significant differences in total yield (Table 3) but they did have differences in yield of number one fruit, average weight of number one fruit, yield of number two, and yield of cull fruit. It is not surprising that TI-098 and TI-100 had higher number one fruit weight since they are not true banana-types but more a combination of a banana and a cubanelle (Figures 1-3). Table 1. in bushels/acre and grades of four poblano peppers grown at the Southwest Michigan Research and Extension Center, Benton Harbor, Michigan, in 2013. Plant population was approximately 10,560 plants per acre. Selection Seed* Source Total No. 1 Avg. No.1 Wt. (gms) No.2 Cull San Ardo UA 1,196 910 98 189 97 Masivo UA 1,143 820 101 147 177 Master UA 1,116 903 92 147 66 USAPX 10307 UA 1,079 869 103 150 60 lsd.05 ns ns ns ns 38 *Seed Source: UA = US Agriseeds Numbers in bold in the same column are not statistically different than the highest number.
Table 2. in bushels/acre and grades of eight jalapeno peppers grown at the Southwest Michigan Research and Extension Center, Benton Harbor, Michigan, in 2013. Plant population was approximately 10,560 plants per acre. Selection Seed* Source Total No. 1 Avg. No.1 Wt. (gms) No.2 Mammoth UA 1,303 1,123 48 109 71 Festa AT 1,295 1,042 45 162 91 Cheetah UA 1,261 1,103 46 98 59 Leopard UA 1,226 1,031 42 104 90 XPP6615 SK 1,194 1,001 43 95 97 J7 AT 1,149 954 51 108 86 Jaguar UA 1,069 857 46 113 99 Tornado UA 970 793 39 122 55 lsd.05 327 261 10 ns ns *Seed Source: SK = Sakata Seed, AT = American Takii, UA = US Agriseeds Numbers in bold in the same column are not statistically different than the highest number. Cull Table 3. in bushels/acre and grades of five banana peppers grown at the Southwest Michigan Research and Extension Center, Benton Harbor, Michigan, in 2013. Plant population was approximately 10,560 plants per acre. Selection Seed* Source Total No. 1 Avg. No.1 Wt. (gms) No.2 Cull TI-098 AT 1,495 1,028 100 328 138 RPP28757 SY/RG 1,426 978 60 222 227 USAPX 10130 UA 1,401 1,006 61 124 272 USAPX 10630 UA 1,302 913 65 117 271 TI-100 AT 1,191 762 102 181 248 lsd.05 ns 251 15 114 128 *Seed Source: SY/RG = Syngenta/Rogers, AT = American Takii, UA = US Agriseeds Numbers in bold in the same column are not statistically different than the highest number.
Figure 1. Specialty pepper entries in the 2013 SWMREC specialty pepper trial. Front row (from left): RPP28758, XPP6615, Leopard, Cheetah, and Jaguar. Second row (from left): Mammoth, Tornado, USAPX 10130, USAPX 10630 and Masivo. Third row (from left): Master, San Ardo, USAPX 10307, TI-100, and TI-098. Back row (from left): Festa and J7.
Figure 2. Top row (from left): RPP28757 and USAPX 10130. Bottom row (from left): USAPX 10630 and TI-100.
Figure 3. TI-098. Midwest Vegetable Trial Report for 2013
Figure 4. Top row (from left): XPP6615 and Leopard. Bottom row (from left): Cheetah and Jaguar.
Figure 5. Top row (from left): Mammoth and Tornado. Bottom row (from left): Festa and J7.
Figure 6. Top row (from left): Masivo and Master. Bottom row (from left): San Ardo and USAPX10307.