Fall 2007 Commercial Fruit & Vegetable Variety Trials
January 2008 Regional Bulletin 20 Auburn University North Carolina State University Alabama Agricultural Experiment Station Richard Guthrie, Director Auburn University, Auburn, Alabama
Printed in cooperation with the Alabama Cooperative Extension System (Alabama A&M University and Auburn University)

Contents
page Authors........................................................................................................................................................................4 Tips for Interpreting Vegetable Varieties Performance Results ..................................................................................5 Alabama Trials Several Bell Pepper Varieties Resistant to Tomato Spotted Wilt Virus ......................................................................7 New Looseleaf Lettuce Varieties Top Standards ........................................................................................................9 Performance of Muscadine Grape Varieties in Central Alabama ............................................................................. 11 Several Types of Chinese Greens Grown in Central Alabama .................................................................................12 Results of the 2007 National Sweetpotato Collaborators’ Trial................................................................................13

North Carolina Trials Asparagus Cultivar Evaluation, 2007-2008 ..............................................................................................................14 Selected Sources for Vegetable Seeds ...................................................................................................................17

Information contained herein is available to all persons without regard to race, color, sex, or national origin.

Issued in furtherance of Cooperative Extension work in agriculture and home economics, Acts of May 8 and June 30, 1914, and other related acts, in cooperation with the U.S. Department of Agriculture. The Alabama Cooperative Extension System (Alabama A&M University and Auburn University) offers educational programs, materials, and equal opportunity employment to all people without regard to race, color, national origin, religion, sex, age, veteran status, or disability.

Authors
Randy Akridge Superintendent Brewton Agriculture Research Unit P.O. Box 217 Brewton, AL 36427 (251) 867-3139 Jason Burkett Superintendent E.V. Smith Research Center Shorter, AL 36075 (334) 727-6159 Carl Cantaluppi Extension Area Agent, Horticulture North Carolina Cooperative Extension Service Person County Center Roxboro, NC 27573 (336) 599-1195 Arnold Caylor Superintendent North Alabama Horticulture Research Center Cullman, AL 35056 (256) 734-5820 Elina Coneva Assistant Professor and Extension Specialist Department of Horticulture Auburn University, AL 36849 (334) 844-7230 Joe Kemble Professor and Extension Vegetable Specialist Department of Horticulture Auburn University, AL 36849 (334) 844-3050 kemblejm@auburn.edu Edgar Vinson Research Associate IV Department of Horticulture Auburn University, AL 36849 (334) 844-8494 vinsoed@auburn.edu Bryan Wilkins Research Associate IV Department of Horticulture Auburn, University, AL 36849 (334) 844-3038

Introduction: Tips for Interpreting Vegetable Varieties Performance Results
Edgar Vinson and Joe Kemble The fall 2007 variety trial bulletin includes results from Auburn University and North Carolina State University. The information provided by this report must be studied carefully in order to make the best selections possible. Although yield is an essential part of varietal performance, other information must be studied. The following provides a few tips to help adequately interpret results in this report. Open pollinated or hybrid varieties. In general, hybrids (also referred to as F1) produce a more uniform crop and have improved disease, pest, and/or virus tolerance/resistance. As a result of these enhanced characteristics, F1 varieties are often more expensive than open pollinated varieties (OP), and seeds cannot be collected from one crop in order to plant the next crop. Selecting a hybrid variety is the first step toward earliness and quality. Yield potential. Yields reported in variety trial results are extrapolated from small plots. Depending on the vegetable crop, plot sizes range between 100 to 500 square feet. Yields per acre are estimated by multiplying plot yields by corrective factors ranging from 100 to 1,000. Small errors are thus amplified, and estimated yields per acre may not be realistic. Your expected yield cannot be estimated directly from the values reported in these trials; however, the relative differences in performance among varieties are realistic, and can be used to identify best-performing varieties. Statistical interpretation. The coefficient of determination (R2), coefficient of variation (CV) and least significant difference (LSD) are reported for each trial. These numbers are helpful in separating the differences due to small plots (sampling error) and true (but unknown) differences among entries. R2 values range between 0 and 1. Values close to 1 suggest that the test was conducted under good conditions and most of the variability observed was mainly due to the effect of variety and replication. Random, uncontrolled errors were of lesser importance. CV is an expression of yield variability relative to yield mean. Low CVs (less than 0.20) are desirable but are not always achieved. There must be a minimum yield difference between two varieties before one can statistically conclude that one variety actually performs better than another. This is known as the Least Significant Difference (LSD). When the difference in yield is less than the LSD value, one cannot conclude that there is any real difference between two varieties. For example, in the lettuce trial presented in this issue conducted at the Brewton Agricultural Research Unit, ‘Rubicon’ yielded 7,024 pounds per acre, while ‘Paramount’ and ‘Red Eye Cos’ yielded 5,716 and 3,971 pounds per acre, respectively. Since there was less than a 2,173 difference between ‘Rubicon’ and ‘Paramount’, there is no statistical difference between these two varieties. However, the yield difference between ‘Rubicon’ and ‘Red Eye Cos’ was 3,053, indicating that there is a real difference between these two varieties. From a practical point of view, LSD values are the most useful for interpreting results. Trial conditions. AU vegetable variety trials are conducted under standard, recommended commercial production practices for Alabama. If the cropping system to be used is different from that used in the trials, the results of the trials may not apply. Information on soil type (Table 1), planting dates, and production methods is provided to help compare specific practices to the standard in order to make relevant adjustments. Ratings of trials. At each location, variety trials were rated on a 1 to 5 scale, based on weather conditions, fertilization, irrigation, pest pressure, and overall performance (Table 2). Results from trials with ratings of 2 and under are not reported. These numbers may be used to interpret differences in performance from location to location. The overall rating may be used to give more importance to the results of variety performance under good growing conditions. Where to get seeds. Because seeds are living, their performance and germination rate depends on how old they are, where and how they were collected, and how they have been handled and stored. It is always preferable to

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get certified seeds from a reputable source, such as the ones listed in Selected Sources for Vegetable Seeds. Several factors other than yield have to be considered when choosing a vegetable variety from a variety trial report. The main factors are type, resistance and tolerance to diseases, earliness, and of course, availability and cost

of seeds. Although seed cost might seem high, purchasing the best quailty seed of recommended varieties is a critical step in the production of quaoity produce. It is always better to try two to three varieties on a small scale before making a large planting of a single variety.

Table 1. Soil Types at the Location of the Trial Location
Gulf Coast Research and Extension Center (Fairhope) Brewton Agricultural Research Unit (Brewton) Wiregrass Research and Extension Center (Headland) Lower Coastal Plain Research and Extension (Camden) EV Smith Research Center, Horticultural Unit (Shorter) Chilton Area Horticultural Substation (Clanton) Upper Coastal Plain Research and Extension Center (Winfield) North Alabama Horticultural Research Center (Cullman) Sand Mountain Research and Extension Center (Crossville) Water holding capacity (in/in) 0.09-0.19 0.12-0.14 0.14-0.15 0.13-0.15 0.15-0.17 0.13-0.15 0.13-0.20 0.16-0.20 0.16-0.18 Soil type Malbis fine sandy loam Benndale fine sandy loam Dothan sandy loam Forkland fine sandy loam Norfolk-orangeburg loamy sand Luvernue sandy loam Savannah loam Hartsells-Albertville fine sandy loam Wynnville fine sandy loam

Table 2. Description of Ratings
Rating 5 4 3 2 1 Weather Very Good Favorable Acceptable Adverse Destructive Fertilizer Very Good Good Acceptable Low Very Low Irrigation Very Good Good Acceptable Low Insufficient Pests None Light Tolerable Adverse Destructive Overall Excellent Good Acceptable Questionable Useless

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Several Bell Pepper Varieties Resistant to Tomato Spotted Wilt Virus
Joe Kemble, Edgar Vinson, and Jason Burkett A bell pepper variety trial was conducted at E.V. Smith Research Center (EVSRC) in Shorter, Alabama, (Tables 1 and 2). On May 31, 10 five-week-old pepper varieties were transplanted into plots that were 20 feet long on 5-foot centers. Plants within a row were spaced at 1.5 feet. Plastic mulch and drip irrigation were used. Experimental plots were arranged in a randomized complete block design. Soils were fertilized according to the recommendations of the Auburn University Soil Testing Laboratory. Current recommentations for commercial vegetable crops can be found in the “Southeastern U.S. Vegetable Crop Handbook.” Copies are available from your local Extension agent and online at www.aces.edu/com_veg. Bell peppers were harvested on August 7, August 16, and August 22. Fruits were harvested at the mature green color stage, weighed, and graded (Table 3) using the USDA grade standards (Circular AHR-784 of the Alabama Cooperative Extension System). The mature green stage is the point when developing fruit can be removed from plants and continue to ripen.
Table 1. Ratings of the 2007 Bell Pepper Variety Trial1
Location EVSRC Weather 3 Fertility 5 Irrigation 5 Pests 5 Overall 4.6 1 See introduction for description of ratings scales

‘X3R Camelot’ is the market standard in this study. Tomato spotted wilt tolerant/resistant varieties ‘Stiletto’ and ‘Heritage’ were similar to the market standard ‘X3R Camelot’ in total marketable yield. In total marketable number, all varieties were similar to ‘X3R Camelot’ with the exception of ‘Valencia’ which was statistically lower. Due to weather conditions, sunscald developed on most of the fruit. Fruit with sunscald are culled. Canopy cover is essential to preventing the development of sunscald. ‘Queen’, known for its excellent leaf cover, had one of the lowest percentages of sunscald. ‘Mavras’ had the lowest percentage of sunscald.

Table 2. Seed Source, Fruit Characteristics, and Relative Earliness of Selected Bell Pepper Varieties
Seed Fruit Days Disease tolerance/ source color to harvest resistance X3R Camelot F1 Seminis Green-Red 74 BLS(1,2,3),TbMV Heritage F1 Harris Moran Green-Red — BLS(1,2,3,5), TSW Ironsides F1 Seminis Green-Red 70 BLS(1,2,3) Lafayette F1 Rogers Green-Yellow 75 BLS(1,2,3), PeMV, PVY Lilac F1 Rogers White-Lilac-Red 68 Stip, TMV Mavras F1 Siegers Green-Purple 68 TMV Queen F1 Siegers Green-Orange — TMV Stiletto F1 Rogers Green-Red 75 BLS(1,2,3) TSW Valencia F1 Rogers Green-Gold 75 Stip, TbMV X3R Wizard F1 Siegers Green-Red 73 BLS(1,2,3) TbMV Type: F1 = Hybrid. Disease claims: BLS=Bacterial Leaf Spot; TbMV=Tobacco Mosaic Virus; TSW=Tomato Spotted Wilt; PeMV=Pepper Mottle Virus; PVY=Potato Virus Y; TMV=Tobacco Mosizc Virus. — = not available from seed catalogues Variety Type

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Table 3. Performance of Selected Bell Pepper Varieties
Total Total number Total number of culls Total cull weight marketable of marketable (nonmarketable (nonmarketable yield fruit number) weight) lbs/A no/A no/A lbs/A X3R Camelot 7,469 27,514 13,920 2,543 Heritage 6,390 28,275 22,946 2,715 Stiletto 6,319 29,689 31,320 4,106 X3R Wizard 6,041 23,816 15,008 2,381 Lafayette 5,563 20,554 19,140 3,232 Queen 5,340 25,556 28,928 3,577 Mavras 4,945 22,403 19,140 2,043 Ironside 4,307 22,403 12,724 1,907 Valencia 4,156 17,509 39,259 5,252 Lilac 3,431 19,901 55,136 5,321 R2 0.60 0.50 0.80 0.70 CV 44 41 33 38 LSD 1,305 11,683 10,159 685 1 Sunscald fruit=Percent of total fuit harvested that were culled due to sunscald. Variety Sunscald fruit1 pct 36 23 20 16 24 14 12 22 17 21 • • • Individaul fruit weight lbs 0.12 0.10 0.10 0.11 0.12 0.09 0.10 0.09 0.10 0.08 0.53 17 0.025

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New Looseleaf Lettuce Varieties Top Standards
Joe Kemble, Edgar Vinson, and Randy Akridge In 2007, a lettuce variety trial was conducted at the Brewton Agriculture Research Unit in Brewton, Alabama (Tables 1 and 2). On October 10, five-week-old butterhead, looseleaf, and Romaine lettuce transplants were set in staggered double rows with a 12-inch spacing between plants within a row. Plots were covered in white plastic mulch and drip irrigation was installed. Plots were 20 feet long on 6-foot centers. This created a stand of approximately 7,200 plants per acre. Experimental plots were arrange in a randomized complete block. Soils were fertilized according to the recommendations of the Auburn University Soil Testing Laboratory. Current recommentations for commercial vegetable crops can be found in the “Southeastern U.S. Vegetable Crop Handbook.” Copies are available from your local Extension agent and online at www.aces.edu/com_veg. Lettuce was harvested and graded according to the Standards for Grade of Lettuce (U.S. Dept. of Agriculture Publication 60-6130) (Table 3).
Table 1. Ratings of the 2007 Letteuce Variety Trial1
Location BARU Weather 5 Fertility 5 Irrigation 5 Pests 5 Overall 5 1 See introduction for description of ratings scales

In this year’s trial there were only two varieties each for butterhead and looseleaf lettuce types. Overall, yields for butterhead and looseleaf were lower this year than last year with butterhead types yielding half as much as last year. There were no significant differences found in varieties of either type. Among the Romaine types the yield of ‘Rubicon’ was significantly higher than that of ‘Red Hot Cos’ and ‘Athena’. ‘Rubicon’ was similar to all other varieties. Numerically, ‘Rubicon’ produced more marketable heads than the other Romaine lettuces, but statistically ‘Rubicon’ outproduced only ‘Athena’ in terms of total marketable heads.

Table 2. Seed Source, Earliness, and Disease Claims of Selected Lettuce Varieties
Seed Days Leaf Disease Years Variety Head type source to harvest color claims evaluated Athena Romaine Enza Zaden/Siegers 63 Green CRR,DM,LMV,TB 02-04, 06,07 Bergam’s Green Looseleaf Siegers 57 Green CRR, TB 06,07 Green Towers Romaine Harris 74 Green — 02-04,06,07 Optima Butterhead Vilmorin\Siegers 55 Green DM,LMV 95-97,02-04, 06,07 Paramount Romaine Siegers 60 Green CRR Red Butter Butterhead Siegers 61 Green-Red — 06,07 Red Eye Cos Romaine Stokes — Red — 02-04,06,07 Red Hot Cos Romaine Stokes 70 Red — 06,07 Rubicon Romaine Siegers 67 Green CRR, LMV 06,07 Tehema Looseleaf Siegers 53 Green B, CRR, TB 06,07 Disease claims: B=Bolt tolerant/resistant; CRR=Cork Root Rot; DM=Downy Mildew; LMV=Lettuce Mosaic Virus; TB = Tip Burn. — = not available from seed catalogues

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Table 3. Performance of Selected Romaine, Butterhead, and Looseleaf Lettuce Types
Marketable Marketable Average weight heads weight lbs/A no/A lbs/head Optima Butterhead 4,642 6,615 0.71 Red Butter Butterhead 3,570 6,534 0.54 Bergams Green Looseleaf 6,184 7,381 0.83 Tehema Looseleaf 5,594 7,623 0.73 Rubicon Romaine 7,024 7,583 0.92 Paramount Romaine 5,726 7,018 0.82 Red Hot Cos Romaine 5,178 7,381 0.70 Green Towers Romaine 4,893 6,897 0.71 Red Eye Cos Romaine 3,971 6,897 0.57 Athena Romaine 3,360 5,929 0.56 R2 0.60 0.44 0.60 CV 24 11 18 LSD 2,173 1,087 0.20 1 Percent of heads that are marketable compared to total number of heads harvested. Variety Type Marketable heads compared to total heads1 % 67 46 80 72 91 74 67 62 52 43 0.60 23 0.22 Cull heads no/A 323 1,210 363 121 161 726 363 968 726 1,815 • • •

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Performance of Muscadine Grape Varieties in Central Alabama
Elina Coneva, Bryan Wilkins, and Jason Burkett Nine muscadine grape cultivars are being evaluated at the E.V. Smith Research Center in Central Alabama. ‘Early Fry’, ‘Janet’, ‘African Queen’, ‘Darlene’, ‘Black Beauty’, ‘Black Fry’, and ‘Pam’ are muscadine grapes commonly recommended for fresh market. ‘Ison’ and ‘Noble’ are commonly recommended for processing into juice or wine. The experimental block was planted in 1996 and muscadine vines spaced at 20 by 12 feet. Vines were trained to a Geneva Double Curtain (GDC) trellis system. ‘Pam’, ‘Black Beauty’, ‘Early Fry’, and ‘Darlene’ were the best performing fresh market muscadine cultivars in 2007 based on yield, berry size, and fruit quality data. ‘Pam’ had the highest yield—an average of 179 pounds of fruit per vine (see table), which translates to 32,578 pounds per acre at a 20-foot by 12-foot vine spacing with 182 plants per acre. Other cultivars with good cropping potential in this study were ‘Black Beauty’, ‘Early Fry’, and ‘Janet’. ‘African Queen’ grape produced the lowest yield in 2007, when compared to the rest of the fresh market cultivars tested. From the group of processing type muscadine cultivars, ‘Ison’ produced 110 pounds per vine on average, and data for ‘Noble’ yield were not complete. A muscadine grape cultivar grown for fresh market consumption should be large, sweet, and attractive with a relatively thin skin. ‘Darlene’ grape produced the largest berries—an impressive 0.6 ounce on average (see table). ‘Pam’, ‘Black Fry’, and ‘Janet’ also had large size berries (0.5 ounce on average). Average berry size was medium (0.4 ounce) for ‘Ison’ and small (0.1 ounce) for ‘Noble’ processing muscadines grapes. ‘Early Fry’ had the highest soluble solids content—16.7 percent—followed by ‘Darlene’ and ‘Black Beauty’ with 16.1 percent and 15.5 percent soluble solids, respectively. Generally, ‘Ison’ and ‘Noble’,the processing type cultivars, had high berry density, expressed as number of berries per unit shoot length. Among the fresh market muscadine cultivars, ‘Early Fry’ and ‘Black Fry’ had the highest berry density of 18 berries per unit shoot length, followed by ‘Pam’ with 14 berries per unit shoot length. ‘Noble’ was the processing type of muscadine grape with a crop level of 2.7 fruit clusters per unit shoot length. ‘Early Fry’ and ‘Black Fry’ fresh market grapes also produced more than two fruiting clusters per unit shoot length. Although continued evaluation of muscadine grape cultivars in Central Alabama is ongoing, it appears that ‘Pam’, ‘Black Beauty’, ‘Early Fry’, and ‘Darlene’ have a very good cropping potential in Central Alabama, while ‘African Queen’ may not be suitable for production in the central part of the state. Further research is needed to evaluate the muscadine cultivar performance under different environmental conditions in upcoming years.

Performance of Selected Fresh Market and Processing Muscadine Cultivars, E.V. Smith Research Center, 2007
Cultivar Fresh Market Early Fry Black Fry Black Beauty Pam Darlene Janet African Queen Processing Ison Noble Yield lbs/plant 101 90 132 179 71 104 51 110 — Mean fruit size oz. 0.4 0.5 0.4 0.5 0.6 0.5 0.4 0.4 0.1 Soluble solids pct 16.7 8.6 15.5 6.0 16.1 14.2 7.5 13.2 5.6 Berry density no berries/unit shoot length 18 18 2 14 5 8 10 17 37 Crop level no clusters/unit shoot length 2.4 2.1 1.6 1.4 0.9 1.2 1.2 1.4 2.7

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Several Types of Chinese Greens Grown in Central Alabama
Joe Kemble, Edgar Vinson, and Jason Burkett A Chinese cabbage and greens variety trial was conducted at E.V. Smith Research Center (EVSRC) in Shorter, Alabama, (Tables 1 and 2). Six-week-old Napa, Mizuna, and Bok Choi types were transplanted onto plots that were 20 feet long on 6-foot centers on May 31. Plants within a row were spaced on 1.5 foot centers. White plastic mulch and drip irrigation were used. Soils were fertilized according to the recommendations of the Auburn University Soil Testing Laboratory. Current recommentations for commercial vegetable crops can be found in the “Southeastern U.S. Vegetable Crop Handbook.” Copies are available from your local Extension agent and online at www.aces.edu/com_veg. Bok Choi and Mizuna types were harvested on November 29 and Napa types were harvested on December 19. At both harvests, greens were weighed in the field (Table 3). Heads of all types and varieties were marketable once they
Table 1. Ratings of the 2007 Chinese Cabbage Variety Trial1
Location EVSRC Weather 4 Fertility 5 Irrigation 5 Pests 3 Overall 4 1 See introduction for description of ratings scales

reached an appreciable size and had little or no insect damage or other physiological disorder. Since Chinese cabbage and greens are new to the trials, there are not enough data to determine market standards. There were two varieties among the Bok Choi types and they were both statistically similar. Among the Napa types, ‘Greenwich’ was statistically higher than ‘Minuet’ but similar to ‘Lettucy ’ and ‘Rubicon’. In the marketable

Table 2. Seed Source, Fruit Characteristics, and Relative Earliness of Selected Chinese Cabbage Varieties
Variety Joi Choi Mei Qing Choi Early Mizuno Greenwich Lettucy Rubicon Minuet Type Bok Choi Bok Choi Mizuna Napa Napa Napa Napa Seed source Johnny’s Johnny’s Johnny’s Johnny’s Johnny’s Johnny’s Johnny’s Plant Leaf habit color Upright Green Upright Green Looseleaf Green Upright Green Upright Green,Yellow Upright Green,Yellow Upright Green,Yellow Days to harvest 50 45 40 50 45 52 48

Table 3. Performance of Selected Chinese Cabbage Varieties
Variety Joi Choi Mei Qing Choi Early Mizuno Greenwich Lettucy Rubicon Minuet R2 CV LSD Type Bok Choi Bok Choi Mizuna Napa Napa Napa Napa Total marketable yield lbs/A 7,346 5,852 5,436 14,552 10,482 10,427 9,992 0.72 25 3,467 Total marketable number no/A 7,260 7,260 7,260 6,806 6,080 5,082 6,534 0.61 12 1,209 Nonmarketable head number no/A 0 0 0 363 817 1,906 908 . . . Individual head weight lbs 1.0 0.8 0.8 2.1 1.7 2.0 1.5 0.90 18 0.40

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Results of the 2007 National Sweetpotato Collaborators’ Trial
Joe Kemble, Edgar Vinson, and Arnold Caylor National Sweetpotato Collaborators’ trials were conducted at the North Alabama Horticulture Research Center (NAHRC) in Cullman, Alabama (Table 1). The sweetpotato collaborators’ trial was replicated at other universities in the Southeast. The purpose of the trials is to improve sweetpotato yield and quality through the development and testing of new breeding lines. Sweetpotato roots from selected commercial varieties and breeding lines were planted in a heated bed at NAHRC on March 4 for slip production. Slips of two sweetpotato lines were planted on June 12. Varieties were replicated four times. Plots contained two rows that were 40 feet long and 3.5 feet wide. Within-row spacing was 1 foot. Soils were fertilized according to the recommendations of the Auburn University Soil Testing Laboratory and consisted of (per acre) 80 pounds N, 184 pounds P2O5 and 156 pounds K2O total. Current recommentations for commercial vegetable crops can be found in the “Southeastern U.S. Vegetable Crop Handbook.” Copies are available from your local Extension agent and online at www.aces.edu/com_veg. Sweetpotatoes were harvested on September 11. Roots were graded as US No. 1 (roots 2 to 3.5 inches in diTable 1. Ratings of the 2007 Sweetpotato Collaborators’ Trial1
Location NAHRC Weather 5 Fertility 5 Irrigation 5 Pests 5 Overall 5 1 See introduction for description of ratings scales

ameter, 3 to 9 inches in length, well shaped, and free of defects), Canner (roots 1 to 2 inches in diameter, 2 to 7 inches in length), Jumbo (roots that exceed the diameter, length, and weight requirements of the US No. 1 grade, but that are of marketable quality), or cull (roots at least 1 inch in diameter but so misshapen or unattractive that they could not be classified as marketable roots). Marketable yield was calculated by adding the yields of the US No. 1, Canner, and Jumbo grades. Percent US No. 1 was calculated by dividing the yield of the US No. 1 grade by the marketable yield (Table 2).

Table 2. Yield and Grade Distribution of Selected Sweetpotato Breeding Lines and Cultivars
Variety Total marketable 50-lb bu/A 374 370 US No.1 50-lb bu/A 264 209 Canner 50-lb bu/A 79 99 Jumbo 50-lb bu/A 31 62 Percent US No.1 50-lb bu/A 71 56 Cull 50-lb bu/A 26 39

NC99-573* Beaureguard (B94-14 G2) B63** 332 238 54 40 71 17 (B63 G1 LSU) Evangaline 331 203 41 87 61 36 NC Japanese 200 88 112 0 43 31 Covington 162 84 55 22 49 49 L0129* 152 44 108 0 25 23 R2 0.70 0.74 0.68 0.61 0.65 0.41 CV 28 37 33 86 26 49 LSD 123 95 45 44 23 26 Average yields are given on a per acre basis. * = Breeding lines. ** = Modified versions of Beaureguard. US No. 1: Roots 2 to 3.5 inches in diameter, 3 to 9 in length; must be well shaped and free of defects. Canner: Roots 1 to 2 inches in diameter, 2 to 7 inches in length. Jumbo: Roots that exceed the diameter, length, and weight requirements of the above two grades, but are of marketable quality. Percent US No.1: Calculated by dividing the weight of US No.1s by the total marketable weight (Culls not included). Cull: Roots must be 1 inch or larger in diameter and so misshapen or unattractive that they could not fit as marketable roots in any of the above three grades.

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Asparagus Cultivar Evaluation, 2007-2008
Carl Cantaluppi People moving into North Carolina from northern states, where asparagus is commonly grown, oflten want to buy asparagus from local growers. Asparagus is a highvalue horticultural crop that is easy to grow and can bring in extra income for growers. Proper variety selection is important for success, so a 3-acre replicated asparagus cultivar trial was planted at the Garnett Carr farm in Roxboro, North Carolina with 13 cultivars (Table 1). Seeds were sown in the greenhouses of Aarons Creek Greenhouses in Buffalo Junction, Virginia, in late January 2005 and transplants were planted into the field on May 4, 2005 in an Appling Sandy Loam soil. A randomized complete block design with 12 plants per plot and four replications was used. The purpose of this trial was to evaluate new cultivars to see which are the most suitable for commercial production. Since the trial was planted using seedling transplants, no harvest was taken in 2006. This was done to build food reserves in the crown of the plant to strengthen the plant for a two-week harvest in 2007. For more than 20 years, new asparagus varieties that have been released are male hybrids. Asparagus is normally dioecious, meaning that it has male and female reproductive structures (flowers) on separate plants. Female plants expend energy to produce seed while in the fern growth stage. Because of this, female plants produce half as many spears as male plants, which produce no seed. Seeds from female plants fall to the ground and germinate, causing a seedling asparagus weed problem. For this reason, asparagus breeders in the U.S. and other countries have gone with male hybrids obtained from super male parent plants. When these super males are crossed with a female, the majority of the F1 generation is male, with no seeds produced. These super male hybrids yield about three times the amount of the older dioecious open-pollinated varieties, such as Mary Washington. Harvest started on March 15, 2007, with just a few spears each of ‘Grande’, ‘UC 157’, and UC 115’. A frost occurred on March 19, which delayed future spear emergence until March 26. The other cultivars then started to emerge with the exception of ‘Purple Passion’, ‘Dulce Verde’, and ‘Guelph Millennium’, which did not emerge until April 2. The last harvest was taken on April 5. On April 6, April 7, and April 8, we had severe frosts that stopped harvest again. A decision was made to end the 2007 harvest at this time, as the harvest period lasted three weeks, with an actual harvest of two weeks for most cultivars, with one week being lost to frost. Ten harvests were made during the three-week period. ‘UC 157’ yielded the highest and along with ‘Atlas’, ‘Grande’, and ‘Jersey Knight’ had the greatest

Table 1. Breeding Location and Parentage of and Comments on Selected Asparagus Cultivars
Variety Jersey Giant Jersey Supreme Jersey Gem Jersey Knight UC 157 DePaoli Atlas Apollo Grand Purple Passion Dulce Verde Guelph Millennium Breeding location New Jersey New Jersey New Jersey New Jersey California California California California California California California U. Of Guelph Parentage NJ 56 female, NJ 22-8 super male NJ 44P female, NJ 22-8 super male NJ G27 female, NJ 22-8 super male NJ 277C female, NJ 22-8 super male F 109 female, M120 male F600 female clone, M256 male clone F 109 female, unspecified Rutgers male F 109 female, unspecified Rutgers male F 109 female, unspecified Rutgers male Progeny of Vileta d’ Albinga — — Comments — — — — Dioecious hybrid Dioecious hybrid Dioecious hybrid Dioecious hybrid Dioecious hybrid Burgundy, sweeter than green types, Open-pollinated High sugar, Discontinued —

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percentage of large diameter spears, which were 93, 95, 97, and 91 percent respectively. ‘Jersey Giant’, ‘Jersey King’, and ‘Jersey Supreme’ were the second, third, and fourth highest yielders, with 80, 81, and 84 percent large diameter spears, respectively. ‘Jersey Knight’ was the lowest yielding cultivar of the New Jersey male hybrids. ‘Purple Passion’ was a low yielder and a prolific seed producer (from the female plants). However, growers should be able to charge a higher price for it since the spears are purple and it has higher sugar content than green asparagus. ‘Guelph Millennium’ was one of the latest varieties to emerge before the second frost occurrence in 2007, and did not get a chance to fully perform before the harvest was terminated; hence, the yields were low. The drought of 2007 seemed to have no impact on asparagus yields in 2008. At last year’s twilight meeting on August 17 at 6 P.M., 40 people braved the 104 degree heat to see asparagus ferns that received no water all year standing like a green oasis in an Appling Sandy Loam soil. This is a great testament for the extreme drought tolerance of asparagus. In 2008, harvest started on March 22 for most cultivars with the exception of ‘Guelph Millennium’. Cool temperatures occurred below 70 degrees until April 11, when yields accelerated, and ‘Guelph Millennium’ started to emerge. One frost in mid-April set yields back for one week. Then yields increased until it was decided to end the harvest on April 26. The harvest period lasted five weeks, with a good harvest of four weeks for most cultivars, with a one-week slump in yield, due to frost. Twenty-one harvests were made during the six-week period. With the California hybrids, ‘UC 157’ moved from 1st place last year down to sixth place this year and ‘UC 115’ moved from fifth place to eighth place. ‘Apollo’ moved from ninth place to eleventh place. However, ‘Grande’ moved up from eighth place to first place in 2008 and ‘Atlas’ moved from seventh to third place. With the New Jerset hybrids, ‘Jersey Giant’ remained at second place, ‘Jersey Supreme’ remained in

fourth place, ‘Jersey King’ fell from third to fifth place, ‘Jersey Gem’ fell from sixth to ninth place, and ‘Jersey Knight’ fell from tenth to last place. ‘Purple Passion’ fell from tenth to eleventh place. ‘Guelph Millennium’ moved up from twelfth to seventh place, mainly because it started to emerge on April 11, which was 20 days after the other cultivars. Since harvest lasted five weeks, it was able to show more of its full yield potential. The percentage of large diameter spears was greatest with ‘Grande’ (93 percent), ‘Atlas’ (91 percent), and ‘Purple Passion’ (90 percent), followed by ‘UC 157’ and ‘Jersey Knight’ (87 percent), ‘Apollo’ (84 percent), ‘Jersey Supreme’ (83 percent), ‘Jersey Giant’ (82 percent), ‘UC 115’ (81 percent), ‘Jersey King’ (78 percent), ‘Jersey Gem’ (76 percent), and ‘Guelph Millennium’ (71 percent). Spear toughness or tenderness is determined by the tightness of the spear tip, not by spear diameter. A tight spear tip will cause the spear to be tender while a loose tip will cause the spear to be tough and fibrous. As the spear tip opens up or “ferns out,” fiber development starts in the base of the spear to enable the elongated spear to change into a woody stalk to support the weight of the fern, after the harvest season is over. As temperatures increase over 70 degrees F, spears will fern out at shorter heights, causing the grower to pick shorter spears (sacrificing spear height) in order to harvest tender spears. Under cool temperatures below 70 degrees, spears will elongate more before ferning out, enabling the grower to harvest taller spears with tight tips that remain tender. Cultivars that fern out at taller heights enable the grower to harvest spears that weigh more than ones that fern out at shorter heights, with spears that remain tender. ‘Atlas’ had tight spear tips at 9 inches tall, ‘Apollo’ at 11 inches tall, ‘Grande’ at 12 inches tall, ‘UC 157’ at 11 inches tall, ‘UC 115’ at 10 inches tall, and ‘Guelph Millennium’ at 7.5 inches tall. The other cultivars ferned out at shorter spear heights under warm temperatures.

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ALABAMA AGRICULTURAL EXPERIMENT STATION

Table 2.Performance of Selected Asparagus Varieties
Cultivar Total yield lbs/A Weight > 3/8 in.diam lbs (pct) Weight < 3/8 in.diam lb Spears/ plant no

2007 1,155 a1 1,071 a (93 %) 84 bcd 3.1 a UC 157 F1 Jersey Giant 944 ab 752 b (80%) 192 a 3.2 a Jersey King 883 abc 712 b (81%) 171 a 2.9 a Jersey Supreme 860 abc 722 b (84%) 138 abc 2.9 a UC 115 821 abc 697 b (85%) 124 abc 2.2 abc Jersey Gem 734 bcd 581 b (79%) 153 ab 2.6 ab Atlas 717 bcd 684 b (95%) 33 de 1.4 cde Grande 703 bcd 684 b (97%) 19 de 1.7 cde Apollo 555 cd 481 b (87%) 74 cde 1.5 cde Jersey Knight 456 de 414 b (91%) 42 de 1.2 def Purple Passion 151 ef 104 c (69%) 47 de 0.6 ef Guelph Millenium 86 f 42 c (49%) 44 de 0.4 f Dulce Verde 71 f 69 c (97%) 2e 0.2 f 2008 Grande 3,030 a 2,821 a (93%) 209 e 7.6 bc Jersey Giant 2,737 ab 2,263 ab (82%) 474 bc 10.2 a Atlas 2,523 abc 2,298 ab (91%) 225 e 6.8 cd Jersey Supreme 2,485 abc 2,064 ab (83%) 421 bcd 8.7 abc Jersey King 2,458 abc 1,915 b (78%) 543 ab 9.3 ab UC 157 F1 2,385 abc 2,078 ab (87%) 307 cde 7.2 bcd Guelph Millenium 2,332 abc 1,653 b (71%) 679 a 8.7 abc UC 115 2,314 abc 1,875 b (81%) 439 bcd 7.8 bc Jersey Gem 2,071 bc 1,579 b (76%) 492 b 7.7 bc Purple Passion 1,915 bc 1,723 b (90%) 192 e 4.4 e Apollo 1,781 c 1,501 b (84%) 280 de 5.4 de Jersey Knight 1,604 c 1,401 b (87%) 203 e 5.3 de 1 Means with the same letter within columns are not statistically significant, Duncan’s Multiple Range Test, .05 level.

FALL 2007 COMMERCIAL FRUIT & VEGETABLE VARIETY TRIALS

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Selected Sources for Vegetable Seeds
Abbott and Cobb 800-345-SEED www.acseed.com American Takii, Inc. 408-443-4901 www.takii.com Baker Creek Heirloom Seeds 407-924-8917 www.rareseeds.com California Asparagus Seed and Transplants, Inc. 530-753-2437 www.calif-asparagus-seed.com D. Palmer See Co., Inc. Distributed by Clifton Seed Co., Johnny’s Select Seeds, Rupp Seed Co., Seedway, and Siegers Seed. Co. www.dpalmerseed.com Harris Moran Seeds Co. 239-543-7300 www.harrismoran.com Holmes Seed Co. 800-435-6077 www.homesseed.com Jersery Asparagus Farms, Inc. 856-358-2548 www.jerseryasparagus.com Johnny’s Select Seeds 877-564-6697 www.johnnyseeds.com Kelly Seed Company 334-588-3821 800-654-0726 Nunhems Seed Company 800-733-9505 www/nunhemsusa.com Rispens Seeds Inc. 888-874-0241 www.rispensseeds.com Rogers Brand/Syngenta Seeds, Inc. Distributed by Clifton Seed Co., Seedway, and Siegers Seed Co. www.reogersadvantage.com Ronniger’s Potato Farm LLC 877-204-8704 www.ronnigers.com Rupp Seeds Inc. 800-700-1199 www.ruppseeds.com Sakata Seed America, Inc. Distributed through Siegers Seed Co., Seedway, Inc., and Twilley Seed Company, Inc. www.sakata.com Seeds of Change 888-762-7333 www.seedsof change.com Seedway, LLC 800-952-7333 www.seedway.com Segrest Feed and Seed Co. Slocomb, AL 334-886-2371 Siegers Seed Company 800-962-4999 www.siegers.com Seminis Vegetable Seeds, Inc Distributed by Kelly Seed Co., Rupp Seed Co., Seedway, Inc., Seminis Vegetable Seeds, and Siegers Seed Co. 229-382-1815 www.seminis.com Stokes Seeds, Inc. 800-396-9238 www.stokesseeds.com Tomato Growers Supply Company 888-478-7333 www.tomatogrowers.com Twilley Seed Co., Inc. 800-622-7333 www.twilleyseed.com Vermont Bean Seed Co. 800-349-1071 www.vermontbean.com Willhite Seed Inc. 800-828-1840 www.willhiteseed.com

Guidelines for Contributions to the Vegetable Variety Regional Bulletin Vegetable variety evaluation and selection is an essential part of production horticulture. The vegetable variety regional bulletin is intended to report results of variety trials conducted by research institutions in the Southeast in a timely manner. Its intended audience includes growers, research/extension personnel, and members of the seed industry. Timeliness and rapid turnaround are essential to better serve our audience. Hence, two bulletins are printed each year: one in November with results from spring crops, and another one in April or May with results from summer and fall crops. It is essential that trial results are available before variety decisions for the next growing season are made. Results pertaining to variety evaluation in a broad sense. This includes field performance, quality evaluation, and disease resistance. Here are a few tips: • Follow the format used in the other regional bulletins. • Include each author’s complete mailing address, e-mail address, and phone number. • Follow your own unit’s internal review process. Contributions will be edited, but not formally reviewed. Send a disk and hard copy to Edgar Vinson or Joe Kemble Department of Horticulture 101 Funchess Hall Auburn University, AL 36849-5408 Or send e-mail to vinsoed@auburn.edu kembljm@auburn.edu

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2 1 3

AUBURN UNIVERSITY 1. E.V. Smith Research Center, Shorter, AL 2. North Alabama Horticulture Research Center, Cullman, AL 3. Brewton Agricultural Research Unit, Brewton, AL NORTH CAROLINA STATE UNIVERSITY 4. Garnett Carr Farm, Roxboro, NC