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Until recently, commercial grape producers in Alabama and the Southeast have been restricted to growing native muscadines and hybrid bunch grape cultivars due to the looming presence of Pierce's Disease (PD), caused by Xylella fastidiosa, an endemic xylem clogging bacterium that is deadly to susceptible European (Vitis vinifera) grapevines.

In response to the spreading threat of PD in California vineyards, the U.C. Davis grape breeding program is developing high quality PD resistant European grape selections. Three of their advanced selections were obtained and planted in 2010 at an experimental vineyard at the Chilton Research and Extension Center (CREC) located in Chilton County, AL to examine the feasibility of cultivation within Alabama's high Pierce's disease pressure environment. Detailed research is being conducted to assess the phenological development, vine physiological responses, and fruit quality characteristics for the three experimental selections, namely: '502-10', '502-01', and '501-12'.

A new crop for Alabama, European grapevines are trained in a different manner than muscadine grapes. The training system facilitates the upright growing habit of European grape cultivars. Rather than allowing fruiting canes trained to a single-wire bi-lateral cordon to grow downwards, V. vinifera fruiting canes are instead trained upwards and periodically directed within a vertical shoot positioning (VSP) system. This training system facilitates efficient pest management practices, while concentrating the crop load within a compact fruiting zone (Fig. 1).  

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Figure 1. Ripening clusters of V. vinifera selection '502-01' within fruiting zone of a VSP trained vine at the Chilton REC, AL, 2017.

Studying the vines' development throughout the growing season allows for development of proper management techniques in a given set of environmental conditions. For the three selections, bud break usually occurs by the first week of April and canopy formation is completed by late April. Flowering is initiated in the first days of May, and full bloom occurs within a week.

Veraison is the stage associated with grape ripening. It starts when the berries start turning their color from green to black or fully colored berry, and sugar accumulation increases. Veraison takes about 40-50 days depending on the particular cultivar and continues until harvest. The three selections studied vary in color accumulation timing, with '502-10' being fully colored early season, usually in July, and attains maturity in mid-August. The remaining two selections complete veraison stage in late September and mid-October.

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Figure 2. 2012-2017 cumulative yield of PD resistant European grape selections grown at the CREC, Clanton, AL.

For the period of 2012-2017, the total cumulative yield per vine was 85.7 lb for early ripening selection '502-10', with an average per season yield per vine of 14.3 lb (Figure 2). The highest cumulative yield of 94.9 lb/vine was recorded for the late ripening '501-12' with an average per season crop of 15.8 lb. Yield data indicates all of the studied PD resistant European grape selections are highly productive in Alabama environment, producing well above the suggested optimal crop level for vinifera grapes of between 8 and 12 lb/vine.   

None of the experimental vines studied under Alabama's high PD pressure conditions have exhibited PD symptoms and there have been no vine losses resulting from other pathogens. The results for vine growth, performance, and fruit quality are very promising demonstrating the PD resistant European grape selections have the potential to diversify and improve the grape production sustainability in the southeastern region and enhance the local food systems.

 

Elina Coneva

Ext. Fruit Crops Specialist, ACES


I get a lot of questions every year about saving vegetable seeds. I think most people know that if you save seeds from hybrid plants you will have a lot of genetic diversity in the offspring. Some of the plants may have characteristics you like, but you will not know that until you grow it. However, saving seeds from open pollinated plants will come back true like the parent, as long as it is not crossed with another. 

What I mean is if you only plant one kind of open pollinated watermelon, then the seeds should come back true the following planting.  However, if you plant more than one open pollinated watermelon in the same area that bloom at the same time, then the chance of crossing is great, and you might not want to save the seeds. You can save the seeds to grow another watermelon, but the offspring may not be exactly like the parent. It may have characteristics of both parents, and the offspring could be better than the parents or it could be worse. For example, you could have one tomato with great fruit but with terrible disease problems that you cross with a tomato with bad fruit but very disease resistant. Crossing a plant is as simple as moving pollen from the bloom of one plant to the pistil of another. Your cross will produce a fruit, you will harvest the fruit, then save the seeds and plant them. You are expecting to produce a tomato that has good disease resistance and produces good fruit. However, the new plant could produce terrible fruit and have major disease problems. Plant breeders will make many crosses, produce many offspring, grow many plants, evaluate the plants, and destroy the inferior plants. They will cross the plants that have the characteristics they like and repeat the process many times. It will take 6 or 8 generations for a tomato breeder to develop a pure line. A pure line, if not crossed with another tomato, will come back true. 

A hybrid is made by crossing two or more pure lines. Hybrid plants can add beneficial characteristics such as hybrid vigor and disease resistance to the plant. This process takes a lot of time, but can be fun. If you are not interested in having this kind of fun, I would recommend purchasing seeds from a reliable source. Many seed sources are available and a grower will be able to find open pollinated or hybrid seeds of tomatoes, watermelon, sweet corn, etc. If you have any questions about saving seeds, give us a call at your local Extension Office.

 Chip East

Regional Extension Agent


Below is a link to a survey for Alabama Extension. If you grow fruit and vegetables commercially in Alabama or are looking to get started growing, we would appreciate your response to a couple questions. We aim to provide economic support to the growers in the state and this survey relates to budgets a farm might use as part of their operation. Currently ACES has budgets available for horticulture but some are a little dated, and some have not been developed as of yet. If you provide a couple quick, honest responses for us we can make sure we're providing helpful and effective education. ACES wants to serve citizens of Alabama and even be a leader in the southeast. We appreciate your responses and please let us know how to continue to serve you. Responses will be accepted until November 10th. Please contact Kevin Burkett for any questions.

Click here for survey.

Kevin S. Burkett, MTA, CPA

Regional Extension Agent I – Farm & Agribusiness Management

Chilton County Extension Office



xentari and pyganic on cabbage1.jpgSeveral species of caterpillars are common to leafy greens and brassica crops. Those include armyworms, diamondback moths, cabbage loopers, cabbage white butterfly (AKA imported cabbageworm), cross-striped cabbageworm, etc. The caterpillars come from eggs that are in clusters or singly on various parts of the plant, usually hidden from predators. Here are control recommendations to lesser the caterpillar load on your crop.

  • Small farms and urban gardens can use low-cost pest exclusion as the first defense strategy by using light weight insect barriers such as Super Light Insect Barrier or the AgriFabric Pro. With this system, the overall caterpillar numbers can be significantly reduced.
  • In terms of using microbial insecticides in organic or other situations, start with a Bacillus thuringiensis or Bt formulation like DiPel, Xentari., etc. There are also virus formulations like Spod-X that are specific to a species and also some newer products like Chromobacterium extracts like Grandevo. Remember to use these materials at low pest pressures to prevent outbreaks. 
  • Several years of testing with various summer and fall crops in Alabama has shown that Xentari (a Bt formulation) is very effective for controlling armyworms like the beet, cross-striped, and fall armyworms. Xentari also does well against other species. The Bt formulations are similarly priced, and come in a variety of formulations and packaging. Make sure you mix up a fresh batch of microbial insecticides and use quickly – don't store a spray solution for several days. Store the original containers away from direct sunlight, especially the living insecticides like Bts and viruses.
  • Spinosad-containing products like Entrust and Monterey Home and Garden Spray are effective at high pest pressure; however, those products are not living insecticides and insecticide resistance could be an issue if you live in an area known for insecticide failure.
  • Tests in Alabama have also shown that Bt can be tank-mixed with natural pyrethrin or Pyganic for a very good synergistic effect which can knockback a rising caterpillar pressure and improve crop quality (see image above). In other words, tank-mixes can work for mid-season caterpillar control in brassicas, but ensure thorough applications multiple times for best effect.
  • There are also insecticide pre-mixes that are available in organic and conventional production systems. Currently, we are testing several pre-mixes in Alabama such as Leap that has Bt and a fungicide for summer crops. With all the products, at least weekly sprays may be needed depending on caterpillar activity and abundance. Use insect pheromone traps for monitoring moth activity that can indicate upcoming problem.
  • When treating brassicas, it is easier to do a thorough spraying when the leaves are small and upright. With waxy leaves, remember to add an appropriate sticker-spreader to allow the leaf to wet and retain the insecticide. Spray from bottom to the top of the canopy during evening hours, targeting the underside of leaves and let the excess solution drop to the ground. In this way, producer can maximize insecticide efficacy, increase persistence, and reduce insecticide need.
  • Remember to stop using organic and conventional insecticides since natural enemies can be affected by continuous foliar applications. For example, lady beetle and lacewing larvae can be easily drowned with excessive leaf wetness due to over-applications of insecticides.

Related article:  Pest alert for high tunnel crop producers (basic scouting/pest identification)

Ayanava Majumdar, Extension Entomologist 

and State SARE Coordinator


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Eleven Pierce's disease (PD) tolerant American and French-American hybrid bunch grape cultivars including 'Black Spanish', 'Blanc du Bois', 'Champanel', 'Conquistador', 'Cynthiana', 'Favorite', 'Lake Emerald', 'Stover', 'Villard Blanc', 'Seyval Blanc' and 'Seyval Blanc' grafted on Coudrec 3309 rootstock ('Seyval Blanc'/3309C) were planted at the Sand Mountain Research and Extension Center (SMREC) in Crossville, AL in 2008 to study the vegetative and cropping potential of PD tolerant hybrid bunch grape cultivars in Alabama environment. Our long-term assessment results indicate that 'Champanel' has the most vigorous vegetative growth, while 'Seyval Blanc' and 'Seyval Blanc'/3309C were the weakest growing cultivars. 'Stover' has the earliest shoot development, while 'Champanel' and 'Cynthiana' shoot development is late. Typically 'Seyval Blanc' and 'Seyval Blanc'/3309C have the earliest fruit maturity and are harvested in mid-August. Due to the warmer 2017 season, harvest started in late July, about two weeks earlier.  'Champanel' produced the largest yield of 56 lb/vine and had the largest berries of 4.2 g. 'Favorite', 'Black Spanish', Blanc du Bios', 'Villard Blanc', 'Stover' and 'Lake Emerald' produced between 31 and 54 lb/vine in 2017.  When we compare the cumulative yield per vine for the period 2011-2017, 'Villard Blanc' shows the highest cropping potential with an average of 230 lb/vine, followed by 'Favorite' with 212 lb/vine and 'Black Spanish' with 176 lb/vine (Figure 1). 'Villard Blanc' and 'Favorite' also produced the largest fruit clusters of 194.6 and 192.0 g respectively. 

Based on their overall performance 'Villard Blanc', 'Black Spanish' and 'Blanc du Bois' are considered suitable for commercial production in Alabama and the Southeast. In addition to their high cropping potential, attractive large fruit clusters, and resistance to berry rot diseases 'Champanel' and 'Favorite' are considered suitable for home grape production with least pesticide application.

Cumulative yield of grape varieties

Elina Coneva, Extension Fruit Crops Specialist


​The Alabama Cooperative Extension System along with the Farmer's Market Authority and USDA SNAP will be hosting Farmers Marketing Workshops in multiple counties from October through November. These workshops will cover market displays, business marketing, social media, food safety and farmers markets. The workshops run from 10AM to 2:30PM with lunch included. To register please call the extension office of the location you would like to attend. The workshops are offered on October 11, in Macon County, (334) 727-0340 dzh0046@aces.edu, October 13, in Montgomery County (334) 270-4133 tysonlk@aces.edu, October 24, in Dallas County (334) 875-3200 nelsoc3@aces.edu, October 26, in Wilcox County (334) 682-4289 alc0074@aces.edu, and November 2, in Hale County (334) 624-8710 srb0043@aces.edu.

See the event flyer for more details.


Inspection Report Week of September 4, 2017

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The pictures above show damage done to the bark at the base of a 'Sunshine' ligustrum by European pepper moth.  Plant symptoms are often similar to frost cracking of bark.  The plant may live for a long time after the damage is done and the caterpillar is gone.  The left stem above was injured months ago and is not dying back, while the right one has much more extensive bark removal and has the brown leaves.  A caterpillar was found in a very tough cocoon in the bark at the surface.  Compacta and 'Soft Touch' hollies are susceptible to this pest as well.  Conditions favoring rhizoctonia (jammed plants) also favor this pest.  This looks like a bad one.  Literature below says that under greenhouse conditions they can have 8-9 generations per year.

More info here.  

Striped mealybug, verified by Charles Ray at the Auburn Plant Lab, was found scattered across a nursery on a number ofstripedmealybug.jpg azaleas and loropetalums. They were found feeding near the tips and were fairly easy to spot from a low angle.  Predators such as lady bugs help pinpoint mealybugs as well. If ants are seen in a plant, aphids, mealybugs, or honeydew-producing scale are usually present.

More info can be found here.

Florida wax scale (cameo stage) seen at the State Docks.  Perfect stage for a pesticide application…which ain't gonna happen because it's at the State Docks…..

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Albert Van Hoogmoed

AL Dept of Agriculture

Mobile and Baldwin Counties

 


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This report is an update regarding the high tunnel pest exclusion (HTPE) system. This research was started in 2014 with USDA SARE program funds. The HTPE system uses woven black shade-cloth of various grades installed under the sidewalls and at end-walls as permanent pest exclusion system aimed at reducing several large moths and leaffooted bugs. Currently, we have seven on-farm HTPE demonstration locations that utilize a 40 or a 50 percent woven shade cloth from Poly-Tex (MN) or FarmTek (IA). Rapid laboratory-based behavior studies using high tunnel models enabled the quick transfer of information and sharing of interest with producers across Alabama. 2016 and 2017 have been notable years to compare the effectiveness of the HTPE system, especially considering the fact that 2016 was a drought year and 2017 was the exact opposite! Below is a summary of HTPE system based on experience from on-farm studies.

 


Overall benefits of HTPE based on multi-year study:

  • There are remarkable differences between pest exclusion potential of a 40 or 50 percent fabric between a drought year (2016) and cool wet year (2017); refer to the data in the illustration below. Overall, we had great success stopping cabbage and soybean loopers (range 40 to 97 percent) with no outbreaks in the field studies. Armyworms, major pests in open field crop in drought years, were reduced 43 to 70 percent. There have been no tomato hornworm issues inside the tunnels since the moths are very big and cannot go past the fabric. This system makes tomato production very profitable inside a netted tunnel.
  • Producers interested in growing squash and other cucurbits inside the tunnel will be delighted to know that squash vine borers can be reduced 80 to 90 percent inside a netted high tunnel. A 40 percent shade cloth allowed honey bees to pollinate the crop. For higher grades of shade cloth, producers may use a bumblebee box inside the high tunnel to pollinate cucurbit crops.
  • The shade cloth must be tightly installed and clamped on the sides to prevent insects from sneaking in. Many insects like leaffooted bugs and armyworms appear to be very good at exploiting any weakness in the fabric. We have seen them lay eggs on the fabric and small caterpillars migrating to crops by crawling in. If you see egg masses then remove them immediately!
  • There is a tremendous improvement in crop quality as a result of reduced caterpillar and sucking insect pest numbers by using a 40 or 50 percent shade cloth around the side and end walls. In a drought year, when insect outbreaks may occur early and pest pressures may be high (as seen in 2016), it is a good idea to use 50 percent woven shade cloth with wide openings to maximize pest exclusion. In a cool wet year, when the pest lifecycles are delayed and pest pressures are moderate, a 40 percent shade cloth may be sufficient to stop large moths and leaffooted bugs.
  • Since aphids and whiteflies remain a problem in netted tunnels (they are too small to stop), producers can use other light insect exclusion materials like Super Light Insect Barrier or AgroFabric Pro19 to prevent colonization.
  • We have only evaluated black shade cloths in present studies, since it is very commonly used for shading materials and readily available from many vendors. We have been purchasing custom-cut and finished woven fabric at 26 to 50 cent per square foot cost from Poly-Tex, MN. Producers can check with their local vendors for material availability.

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We are working with additional producers statewide for IPM training and on-farm research, so stay connected with ACES for future updates regarding HTPE. If you want more information immediately, then contact the authors or checkout the HTPE webpage on Alabama Vegetable IPM. Producers can also refer to two HTPE bulletins on Southern SARE where preliminary research data was reported along with basic information on IPM tactics. 

Ayanava Majumdar, Extension Entomologist 

Doug Chapman, Regional Extension Agent

Rhonda Britton, Regional Extension Agent


AUBURN, Ala.--Scientists say nurseries in both north and south Alabama are battling the European pepper moth, Duponchelia fovealis. The moth (EPM),a relatively new pest in Alabama,  comes originally from both salt and fresh water marshlands of southern Europe. First reported in the United States in 2004, the pest's range began expanding in Europe in the early 1980's.

Alabama Extension horticulture specialist Dr. Jeremy Pickens said that damage from larvae may be responsible for crop loss between 10 to 20 percent.

Adult moths are mostly nocturnal and grayish brown in color with a wingspan of about 0.75 inches (Figure 1). Larvae are small, segmented caterpillars. At hatching, they measure just under 0.1 inch in length with a dark colored head and salmon body. As they mature, they darken and eventually reach 0.7 to 1.25 inches long (Figure 2).

Fig 1.European pepper moth adult (credit John Olive).jpgFigure 2.  European Pepper Moth larvae (Credit Doug Chapman).jpg

"In northern states, 7 to 8 generations have been observed within a year; however, warmer temperatures can mean shorter lifecycles," Pickens said.  Research results from Bethke (2017) show that EPM can complete development from egg to adult in as as little as 20 days when temperatures stay at or above 90°F.

European pepper moth feeds on all parts of a wide variety of host plants.  In chrysanthemums, noticeable symptoms may first appear as flagging or a slight wilting of new growth (Figure 3).  Eventually, the entire plant will succumb to the damage, wilt and die.  Wilting is a result of feeding damage by stem girdling at the plant base. Also, webbing and frass can be observed in the same area (Figure 3).

Figure 3.  Symptomatic plant. (Credit John Olive).jpg

Be aware damage from EPM on chrysanthemum is easily misdiagnosed as Fusarium.  As growers space plants outdoors, heat stress and excessive moisture can dramatically increase the disease pressure for Fusarium.  The symptoms of Fusarium may include partial wilting of a plant and brown streaking on the outside of stems or in the vascular system of the plant (Figure 5 and 6).  White- or salmon-colored structures may also be present on advanced infections (Figure 7). More information on Fusarium on garden mums can be found at Greenhouse Management and University of Kentucky.  In some cases, both EPM and Fusarium have been confirmed infecting the same plant.

Literature in other states have listed that neonicotinoid, pyrethroid, spinosid and BT products as being effective.  Little control with these products have been observed in south Alabama when these products were applied with high-pressure airblast sprayers.  The dense canopy associated with chrysanthemum may inhibit contact with larvae present at the base of the plant.

Figure 5. Example of necrotic stem from Fusarium (credit John Olive).jpgFigure 6. Brown streaking in tissue. (credit John Olive).jpgFigure 7.  Salmon and white reproductive structures on advanced infection.jpg

In addition, chemical treatments may be more effective if low-pressure nozzles are inserted into the canopy of the plant about 1.5 inches from the soil line where chemicals are more likely to make contact with the pest.  Current recommendations include targeted sprays of contact insecticides such as acephate or bifenthrin.  Acephate seems to be the most effective chemical for use  as a spray or drench.  A study in Florida showed that Enfold (emamectin benzoate) can provide residual control; however, spinosad (Conserve) was not very effective (Bethke et al. 2017).  Regular broadcast applications of Bacillus thuringiensis (XenTari®/DiPel®) may provide some suppression of young larvae.

Pheromone lures are available for monitoring purposes at BIOBEST USA www.biobestgroup.com.

More information about the European Pepper Moth can be found at the following links:

University of Florida IFAS Featured Creatures

University of Kentucky Entomology

University of Maryland IPM Alert

Bethke, J., A. Hara, L. Osborne, C, McKenzie, and C, Palmer, 2017. Developing sustainable methods for controlling invasive pests pre- and post invasion on ornamental cuttings and plants. IR-4 Research Project Report http://ir4.rutgers.edu/Ornamental/SummaryReports/

ArthropodShippingandDuponchelia_USDA-APHIS_ProjectSummary.pdf last accessed 8/29/17.

If you have questions please contact your Alabama Extension regional commercial horticulture agent.

Find your Alabama Extension Commercial Horticulture Agent

 

Doug Chapman, Extension Agent

Jeremy Pickens, Extension Specialist, Greenhouse Nurseries

John Olive, Ornamental Horticultural Research Station

David Held, Associate Professor, Department of Entomology

 

 

 


On Tuesday, October 24th, the Alabama Cooperative Extension System will have a walking tour of fruit and vegetable production at Holmstead Farm in Clay County. This farm is located in Clay County, but it does have a Talladega address of 6582 County Road 7, Talladega, Alabama. Alabama Cooperative Extension Agents Chip East and Dani Carroll will be leading this tour. The topics discussed at this tour include planting, pruning, and proper management of crops such blueberries, muscadines, blackberries, peaches, apples, and strawberries along with vegetable crops. Please call the Clay County Extension office at 256-354-5976 by Friday, October 20th, to register. There is no registration fee, but it helps to know how many will be attending. This will be a very educational meeting for commercial producers as well as home fruit and vegetable growers. If you have any questions about this meeting, please call Chip East at the Clay County Extension office or Bobby Ray Holmes at 256-404-4316. Click here for the event flyer.

On Thursday, November 2nd, a fruit production class will be taught at Founders Station at 4902 Pike Road in Montgomery County. The topics discussed at this meeting include site selection, variety selection, proper planting, mulching, irrigation, pruning, fertilization, and pest management. Crops to be discussed are apples, pears, peaches, persimmons, blueberries, and blackberries. The fruit class will begin at 9:00 a.m. and will last until noon. There is no registration fee, but seating is limited and pre-registration is required. Please pre-register by calling the Montgomery County Extension Office at 334-270-4133 by Wednesday, November 1. If you have any questions about this meeting or to pre-register, please call the Montgomery County Extension Office. 

Chip East, Regional Extension Agent


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