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Category: VSCNews magazine

  • Top 5 Lessons Learned From a Newly Certified Organic Grower

    Tiffany Bailey, owner of Honeyside Farms, with her brother and business partner, Paul Bispham Jr.

    By Tiffany Bailey

    At Honeyside Farms, we have been growing produce using organic practices for over 10 years. When we needed to move farm locations, we found a piece of farmland that could become certified organic. So, we decided to go for it. These are the top lessons we learned in our first year as a fully certified organic farm.

    1: RECORDS ARE YOUR FRIEND

    Before deciding to become certified organic, we spoke with many growers about the benefits and challenges of becoming certified. One of the constant negatives we heard about was intense recordkeeping. The recordkeeping has proven to be intense, but the information we have collected has been extremely valuable. We quickly discovered that we needed to plan recordkeeping into every day.

    We use a series of Excel spreadsheets on a computer to keep track of all our records. At the end of every day, our farm manager cools off in the air conditioning while updating all the spreadsheets with information from that day. This usually takes about 30 minutes. When the season is wrapping up, it has been well worth the time to sit down and analyze how the information we collected can be used to make future decisions.

    2: YOU CAN’T GROW EVERYTHING

    While it may seem obvious that different crops have different costs, it is important to evaluate the costs involved with everything from seeds to post-harvest and handling. Especially on a small scale, not all crops can bring in enough revenue to justify growing and handling them.

    This can be hard, especially when you have an item that is a customer favorite. But it is important to understand all the different types of costs so you can grow what makes sense financially. If you don’t make the money you need, you won’t be able to sell anything to your customers.

    3: NEW GROUND BRINGS NEW CHALLENGES

    If you are going to grow something on a new piece of ground, expect to deal with some new challenges. Sometimes there is just no way of knowing how something will grow until you have your first crop there. Consider growing a lower risk type of crop on the first go-around. This will give you an opportunity to assess things like drainage, nutrient retention and soil insects.

    On one of our new blocks, we discovered a heavy population of mole crickets that fed on our seedlings. It was an expensive discovery, but we did gain knowledge on how to approach new ground.

    4: CAREFULLY SOURCE YOUR LIQUID FERTILIZER

    These days, there are so many Organic Materials Review Institute products to choose from. Many liquid fertilizers have good numbers on the label but can come with some challenges related to clogging filters and drip tape. Make sure you know another grower who has used the product successfully before you commit to using it.

    You may not get everything you need in one liquid blend. You may have to apply certain nutrients through foliar applications or from a dry mix.

    5: THE WORK IS NEVER ALL DONE

    Organic farming is more work — period. You can’t just spray something and have 21 days of control. So, the field is always needing some sort of attention. And let’s not forget about the office work and recordkeeping that come along with complying with organic standards.

    It is important to make an actual list of your priorities. Manage your time well and try to create routines out of repetitive tasks so you can be as productive as possible. Make sure you are taking time to do important things instead of only doing what is urgent. Sometimes, you have to allow some little fires to burn, and that’s OK.

  • Fumigants for Nematode Management in Vegetables

    Bell pepper roots (left) show severe galling caused by the southern root-knot nematode compared with healthy roots (right) treated with Pic-Clor 60.

    By Abolfazl Hajihassani and Chinaza Nnamdi

    The majority of vegetable production in Georgia is located in multiple counties in the southern region of the state. Vegetables are grown year-round on both raised beds covered with polyethylene plastic mulch and on bare ground.

    Using a comprehensive survey conducted in 2018, we have documented that root-knot nematodes, Meloidogyne spp., are the No. 1 nematode pest in vegetable crops in Georgia, infecting 67 percent of the fields surveyed. Therefore, proper management practices need to be developed or optimized for successful control.

    CONTROL OPTIONS

    Chemical control is currently the best option for managing nematodes in vegetable-producing systems. Optimizing chemical control methods is a must for vegetable growers in the Southeast. Growers often fumigate the soil prior to planting the first crop in the spring or in the fall, but the issue with root-knot nematodes is particularly important in the second, third or fourth crop grown on the same plastic mulch. Reusing mulch favors nematode buildup in coarse-textured soils.

    In Georgia, 1,3-dichloropropene (Telone II), chloropicrin, mixtures of 1,3-dichloropropene and chloropicrin (e.g. Pic-Clor 60), metam sodium (Vapam) and dimethyl disulfide (Paladin) have been the common fumigants for the control of soilborne pathogens, weeds and nematodes in vegetable-production systems.

    In a field study conducted at the University of Georgia Tifton campus in 2019, we evaluated the effects of different soil fumigants on the southern root-knot nematode and yield of bell pepper. Treatments included Telone II (125 pounds per acre), Dominus (250 pounds per acre), Pic-Clor 60 (175 pounds per acre), Paladin (167 pounds per acre) and an M. incognita-resistant pepper cultivar (Carolina Wonder).

    RESEARCH RESULTS

    Results showed that all soil fumigants and the resistant cultivar reduced root galling compared to the untreated check at harvest. Pic-Clor 60 had numerically better control of root galling compared to the other fumigants. At the end of the season, second-stage juveniles of the nematode in the soil were only lower than the untreated check in the resistant pepper treatment. Among the fumigant treatments, Paladin had numerically lower nematode numbers in comparison with the other fumigants. We also found that Pic-Clor 60 and the resistant cultivar had the highest and lowest pepper fruit yield, respectively.

    Based on our data, treatments with Dominus and the resistant variety had the highest weed density. Plots treated with Pic-Clor 60 had the lowest weed density. There was no difference in weed density among Paladin, Telone II and the untreated check. The weed population in the Dominus treatment was higher than the check plot. Soil fumigation with Pic-Clor 60 reduced southern blight disease, caused by the fungus Athelia rolfsii, as compared to other treatments.

    Paladin, though effective in suppressing nematode juveniles in the soil, was withdrawn from the market in 2019, further restricting the already limited number of tools for managing nematodes. Pic-Clor 60 is likely an ideal fumigantfor control of root-knot nematodes and other soilborne pathogens in multi-cropping systems of vegetables. However, root-knot nematode population densities in plots treated with Pic-Clor 60 were increased by the end of the growing season. This may suggest that combined use of fumigants and post-plant nematicides through drip irrigation could provide enough root protection against high densities of root-knot nematodes in the first and subsequent crops grown on the same plastic mulch.

    In collaboration with county Extension agents, two on-farm trials are currently being conducted in Brooks and Lowndes counties in Georgia. The objective is to examine whether the combined application of both fumigant and non-fumigant nematicides in the first crop can result in a more effective control of root-knot nematodes and higher crop yield, compared to the use of only fumigants in the first crop and only non-fumigant nematicides in the second crop grown on the same plastic mulch.

  • Hemp growers: Be on the Lookout for Nematodes

    Figure 1. Stunted ‘starving’ strawberry plants (foreground) caused by sting nematodes in Florida.

    By Johan Desaeger

    Florida’s subtropical climate offers unique opportunities to grow crops outside of the typical growing season of other states. Such is the case for strawberries and many vegetables. There are high expectations that hemp could be another such crop, although nematodes may have something to say about that.

    Plant-parasitic nematodes, such as root-knot and sting nematodes, can cause severe damage to many of Florida’s crops, especially in sandy soils, which comprise much of the state (Figure 1). Nematodes are microscopic roundworms that live in the soil and are one of the least-known and most difficult-to-manage pests that growers can face. Because of nematodes’ small size, belowground nature and lack of easily recognizable symptoms, nematode damage is often not recognized as such. Symptoms typically occur randomly in a field and are easily confused with other pests and diseases, nutritional deficiencies, plugged drip tapes or too much or too little water.

    Figure 2. Swollen and galled roots caused by root-knot nematodes on tomato (left) and hemp (right).

    The most important nematodes in Florida are root-knot nematodes. They can cause damage to a wide variety of crops and are extremely widespread throughout the state (Figure 2).

    HEMP HAS SOME NEMATODE TOLERANCE

    With the considerable interest that hemp is gaining in Florida, the Gulf Coast Research and Education Center (GCREC) nematology lab started to investigate how root-knot and other nematodes may affect this new crop. The hemp-nematode research is the focus of Jackie Coburn, a master’s student in the nematology lab.

    Coburn screened several hemp cultivars in the greenhouse at the GCREC, including fiber, seed and CBD (cannabidiol) hemp types, originating from Europe, China and the United States. Initial data show that hemp is a good host for root-knot nematodes (Figure 2). However, the crop appears to be relatively tolerant, meaning the nematodes can feed and reproduce, but do not seem to negatively affect hemp growth.

    Figure 3. Hemp plots at the Gulf Coast Research and Education Center have strings with LED lights and hops in the background.

    Certain CBD varieties showed less nematode root damage than others, which will be useful for future breeding efforts. Currently, Coburn is screening hemp varieties for sting nematode, another important nematode in Florida, especially in strawberry fields (Figure 1).

    In addition to the greenhouse studies, hemp research was also initiated in the field at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) farm in Balm. Here, hemp cultivars are planted throughout the year. In addition to nematode sampling, plants are being monitored for other pests and diseases.

    HEMP-HOPS INTERCROP

    An interesting feature in the field trials here is that hemp is grown with and without adding supplemental light, a practice that has worked well for hops in Florida (Figure 3 and Figure 4). It quickly became clear that adding supplemental light during the vegetative state makes a huge difference when growing hemp. In field trials, hemp was intercropped with hops, and both crops received the same light and fertilizer regimen.

    Figure 4. Hemp (left) and hops (right) at night at the Gulf Coast Research and Education Center.

    Hops and hemp belong to the same plant family, and in addition to both being daylength-sensitive plants, they also share many of the same flavor and aroma compounds. The field trials at the GCREC showed that with supplemental light, a hops-hemp intercrop can be an attractive option, as both crops will similarly benefit, allowing for two hop harvests per year and two to three hemp harvests per year.

    MORE RESEARCH RESULTS TO COME

    With increasing interest in hemp as an alternative crop, we will continue to provide updates on the hemp research at the GCREC. Future focus will be on CBD varieties and how to integrate hemp in the high-value cropping systems (vegetables and strawberries) in our area.

    Finally, in order to help researchers better understand the real importance of nematodes in commercial hemp fields, we invite any hemp grower in Florida to contact us if they notice abnormal plants in their field, or simply wish to have their fields analyzed for nematodes.

    This story was from the August edition of VSCNews Magazine. To subscribe, see http://vscnews.com/subscribe/.

  • Fungicide Resistance in Georgia Strawberry Fields

    Figure 1. Anthracnose fruit rot of strawberry © Catherine Eckert / shutterstock.com

    By Phil Brannen, Md Emran Ali, Jeff Cook, Sumyya Waliullah and Owen Hudson

    Anthracnose fruit rot disease, caused by fungal Colletotrichum species, is one of the most significant disease problems of commercial strawberry production in the Southeast.

    Dark, sunken lesions on fruit are the main disease symptoms (Figure 1). Hot, humid weather and significant rainfall make Colletotrichum-induced fruit rot a widespread problem in strawberry production.

    For disease control, growers mainly rely on preventive fungicide applications from flower bud emergence to harvest. The most used single-site fungicides are quinone outside inhibitors (QoIs). The QoI active ingredients azoxystrobin (e.g., Abound) and pyraclostrobin (e.g., Pristine) are often utilized to manage anthracnose fruit rot. If appropriate resistance-management strategies are not implemented, QoIs are at increased risk of resistance development and subsequent control failure.

    The QoIs have been marketed since 1996, and resistance development is expected with long-term use, but limited surveys and in vitro efficacy tests conducted in 2004 and 2008 did not confirm QoI resistance in Georgia. However, more recently, producers have complained of control failure when using QoI fungicides, and resistance has been confirmed.

    RESISTANCE CONFIRMATION

    In 2019, county agents submitted numerous samples to the Plant Molecular Diagnostic Lab in Tifton, GA. Md Emran Ali, the lab director, collected 108 strawberry fruits with visible rot symptoms to test for fungicide resistance. These samples were from seven different strawberry farms scattered throughout Georgia. The farms had received multiple applications of QoI fungicides during the 2019 growing season, as well as in previous seasons.

    Ali identified all isolates as Colletotrichum acutatum. For further confirmation of QoI resistance, he tested all 108 isolates for the presence of the G143A mutation using the PCR-Restriction Fragment Length Polymorphism assay. His results showed the presence of the G143A mutation in all QoI-resistant C. acutatum isolates, 87 percent of isolates with moderate resistance, but none with reduced sensitivity or sensitive isolates (Table 1). These findings suggest that there is a high risk that resistance has developed in C. acutatum populations wherever QoIs have been utilized over time for control of anthracnose fruit rot in Georgia – and likely elsewhere.

    GROWER RECOMMENDATIONS

    For effective control of this disease, growers need to focus on using multi-site fungicides, such as Captan products, and alternation with classes other than QoIs. The Southeast Regional Strawberry Integrated Pest Management Guide for Plasticulture Production (www.smallfruits.org), edited by Rebecca Melanson of Mississippi State University, provides excellent information on fungicide selection under various conditions of resistance to anthracnose and/or botrytis fruit rots. 

    Moving forward, growers should have their anthracnose populations tested for QoI resistance. Use of QoIs may be limited in future management strategies as a result of widespread resistance development. The Plant Molecular Diagnostic Laboratory, a lab service of the University of Georgia Department of Plant Pathology, is now providing fungicide resistance testing support for several plant pathogens like anthracnose of strawberry. The clinic can accept symptomatic fruit samples (generally 10 per site) to test for resistance.

    In 2019, funds were provided by the Southern Region Small Fruit Consortium for resistance testing of both anthracnose and botrytis — free of charge to producers from member states until the funds ran out. Check with your local county agent on the status of resistance testing funds. If funds are not available, you are still encouraged to have both anthracnose and/or botrytis profiled for your location. The tests currently available, their pricing, a submission form and submission information are available at the Plant Molecular Diagnostic Lab web page at https://site.caes.uga.edu/alimdl/fungicide-resistance-testing/. See the form at https://site.caes.uga.edu/alimdl/files/2019/02/resistant-profile-form-003.pdf.

    Samples can be shipped to:Plant Molecular Diagnostic Lab

    Department of Plant Pathology

    Tifton, CAES Campus

    Plant Science Building

    115 Coastal Way

    Tifton, GA 31794

    For more information of questions, contact Ali at emran.ali@uga.edu, 229-386-7230 or 229-386-7285.

    Growers are highly encouraged to take advantage of this service. It is very important to know the resistance profile for anthracnose at your location — fungicides that should work and those that will not. If you have questions or need help, contact your local county agent for additional information. It is recommended to overnight samples to the Plant Molecular Diagnostic Lab and to communicate with the lab so it can expect the samples on the day of arrival.

    Fungicide resistance can be devastating, so use these services to ensure that the fungicides you are utilizing are active. Spraying inactive fungicides is the equivalent of spraying water on your strawberry plants. If a fungicide is not active, you waste money on the fungicide, and you can lose your entire crop to disease as well — adding insult to injury.

    This story was from the August edition of VSCNews Magazine. To subscribe, see http://vscnews.com/subscribe/.

  • Management of Thrips in Tomatoes

    Cosmetic damage of western flower thrips on tomatoes by (A) oviposition and (B) feeding (flecking).

    By Xavier Martini and Joe Funderburk

    Thrips are important pests of tomatoes for two reasons. First, they damage fruit directly by egg-laying or feeding (Figure 1). More importantly, some species also vector tospoviruses that include tomato spotted wilt virus, groundnut ringspot virus and tomato chlorotic spot virus.

    These tospoviruses can considerably decrease the crop yield if thrips are not controlled. Thrips acquire tospoviruses during the nymphal stage only, but once acquired they can transmit them to plants throughout their lifetime.

    IMPORTANCE OF IDENTIFICATION
    Two thrips species are of concern to tomatoes in the Southeast: western flower thrips (Frankliniella occidentalis) and tomato thrips (Frankliniella schultzei). Both are particularly good vectors of tospoviruses.

    However, other thrips with less economic impact on tomato, such as Florida flower thrips (Frankliniella bispinosa) and flower thrips (Frankliniella tritici),are often found in tomato flowers, sometimes at a higher density than the more damaging thrips. In fact, F. bispinosa and F. tritici compete against the other thrips species that transmit tospoviruses and therefore prevent the spread of tospovirus-associated diseases.

    If insecticides are applied when these undamaging species are dominant, the insecticides will eliminate them, and they will be replaced by the invasive species, such as western flower thrips. Therefore, it is of critical importance to identify thrips before applying an insecticide to tomato crops.

    Thrips identification is based on specific characteristics only visible under a microscope. For most growers, the best method is to collect tomato flowers in ethanol and send them to a scout, an Extension agent or a state specialist for identification.

    CHEMICAL TREATMENTS
    Different insecticide treatments are available against thrips. Neonicotinoids applied at transplant might be an option in areas where tospovirus-related diseases occur every year. Spinosyns offer some of the best control for thrips. They have the advantage of being compatible with biological control and sometimes with organic agriculture.

    It is important to rotate insecticide modes of action during a season to avoid the development of insecticide resistance in thrips populations. The mode of action of each insecticide can be found on the Insecticide Resistance Action Committee website (https://irac-online.org/).

    NON-INSECTICIDAL CONTROLS
    Because identification of thrips is highly recommended before applying an insecticide, it is better to manage thrips using non-insecticidal methods. The addition of companion flowers (such as bidens or coreopsis) on the border of tomato crops increases the density of natural enemies.

    Orius species minute pirate bugs are very efficient thrips predators, and they use pollen in companion flowers as a nutritional supplement. Under field conditions, about one predator to 180 thrips is enough for suppression of thrips populations. When the ratio reaches about one predator to 40 thrips, thrips populations are controlled.

    It is important that the companion plants flower prior to the tomato crops to ensure the buildup of the natural enemies’ population before they are needed to control the thrips population. Natural enemies are available commercially for thrips control in greenhouses and other protected-culture systems.

    The use of UV-reflective mulch instead of the regular black or white mulch is also recommended. UV-reflective mulch disrupts thrips’ host location and reduces significantly the settling of thrips on tomatoes. UV-reflecting mulch is particularly efficient at the earlier stages of the tomato crop (Figure 2). However, as the crop grows, leaves will cover the UV-mulch, and the benefits of the UV-mulch will decrease. At this point, kaolin clay can be applied on tomato crops. Kaolin clay has a repellent effect on thrips and works better on expended leaves.

    The combined use of minute pirate bugs, companion plants, UV-reflective mulch and kaolin (Figure 3) has been shown to be highly effective in controlling thrips in field trials conducted at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) North Florida Research and Education Center. If the timing of these different elements is correct, the need for insecticide to control thrips will be sporadic.

    Xavier Martini (xmartini@ufl.edu) is an assistant professor and Joe Funderburk is a professor, both at the UF/IFAS North Florida Research and Education Center in Quincy.

  • Protecting Peppers From Anthracnose

    Anthracnose lesions can occur on leaves and stems, but infections on the fruit have the largest economic impact.

    By Pam Roberts

    Anthracnose is a serious disease problem that can occur throughout pepper-growing regions worldwide. Extensive outbreaks of the disease have developed on bell and other specialty peppers types, such as hot peppers.

    The disease is more common when both the inoculum and warm weather combined with frequent rains occur. Fruit infections cause significant losses of either mature (red, yellow or orange) or immature (green) fruit due to non-marketability.

    The causal agents of anthracnose are fungi within the genus Colletotrichum. Species of Colletotrichum cause many common plant diseases on a wide variety of different hosts worldwide. Colletotrichum gloeosporioides and Colletotrichum acutatum are the two species found on pepper in Florida, but they have a host range beyond pepper.

    SYMPTOMS AND SPREAD
    C. gloeosporioides     is mainly associated with infecting ripe fruit, whereas C. acutatum produces lesions on immature fruit. Anthracnose lesions can occur on leaves and stems, but infections on the fruit have the largest economic impact.

    Fruit symptoms begin as water-soaked lesions that are soft and slightly sunken. As the lesions age, they appear concentric and become covered with a wet, gelatinous spore mass. Fruit infected with C. acutatum will have lesions that are salmon-colored from their spore mass. C. gloeosporioides lesions will generally be darker in appearance.

    Peppers that are grown in fields with a history of anthracnose are at higher risk. Rainy weather, occurring with temperatures around 80°F or higher, enhances disease spread and increases disease severity due to the spread of spores via splashing onto fruit. In addition to rain splashing, spores may be moved mechanically by workers or equipment that come into contact with infected plants.

    The pathogen is seedborne. Anthracnose may be introduced into the field on infected transplants or it can survive between growing seasons in plant debris or on alternate weed hosts.

    MANAGEMENT MEASURES
    An integrated approach to disease management is required to control anthracnose.

    Select seed sources that are certified or known to be pathogen-free.

    Transplants should be protected from the disease by eliminating weeds and solanaceous volunteers around the transplant facility.

    Fields should have good drainage and be free from infected plant debris. If the disease was previously present, crops should be rotated away from solanaceous plants for at least two years. Field sanitation practices include control of weeds and volunteer peppers plants.

    Resistance is available in some varieties of specialty peppers, such as chile, but not in bell peppers. For bell pepper production, a cultivar that bears    fruit with a shorter ripening period may allow the fruit to escape infection by the fungus through an earlier harvest.

    Wounds are sites of entry for the fungus, so any measures that reduce wounding fruit, such as managing insects and mechanical damage, should help decrease fruit infections. Wounds that can be entry points for Colletotrichum spp. also make the fruit susceptible to other pathogens, such as bacterial soft rot. All crop debris should be destroyed at the end of the season to reduce inoculum survival for infecting subsequent crops.

    Organic growers will need to consider crop rotation, scouting to detect and remove infected fruits, and applications of copper and/or biopesticides approved by the Organic Materials Review Institute.

    For conventional farms, fungicides are effective in managing anthracnose on pepper, but applications need to begin as soon as fruit is set and continue a weekly schedule thereafter. According to several studies, fungicides that are labeled for anthracnose on pepper were effective when used in rotation with chlorothalonil or mancozeb.

    Pam Roberts is a professor at the University of Florida Institute of Food and Agricultural Sciences Southwest Florida Research and Education Center in Immokalee.

    This story was from the July edition of VSCNews Magazine. To subscribe, see http://vscnews.com/subscribe/.

  • Organic Management Methods for Squash Pests

    A squash bug lays its eggs in a crop.

    By Ayanava Majumdar, Rammohan Balusu and Neil Kelly

    Many pests feed on squash from seedling to harvest. They are generally broken down into two groups: the chewing insects and the sucking insects. Chewing insects of squash consist of common pests like cucumber beetle, squash vine borer larva and pickleworm. Sucking insect pests consist of aphids, squash bugs and whiteflies. The pests a squash grower experiences may depend on location.

    PREVENTION STRATEGIES
    Remember that prevention of pests is the No. 1 goal of organic integrated pest management (IPM) systems. Rapid control after pest establishment becomes a difficult aim later in the production season. Cultural control tactics that include selecting virus-resistant varieties, timely planting and harvest (reduces pickleworm buildup), crop rotation and timely removal of crop debris after harvest (reduces squash vine borer buildup), consistent irrigation and trap cropping are some basic preventive approaches, also called Level 1 control.

    Perimeter trap cropping with Baby Blue and New England Hubbard squash in a mixed system is effective in reducing cucumber beetle and squash bug damage to yellow squash (main crop).

    PEST EXCLUSION FABRIC
    For Level 2 control, growers should use temporary or permanent pest exclusion fabric to create a barrier between insect pests and the main crop. Two lightweight materials tested in Alabama include the Super-Lite Insect Barrier (Gardens Alive, Inc.) and AgroFabric Pro 19 (Seven Springs Farm, Inc.). Both these materials look like lighter versions of the common row cover used for frost protection, but these materials are much lighter with 85 to 95 percent light and rain penetration.

    The trick is to put these light fabrics on low hoops (inverted loops) almost immediately after transplanting or after the seeds have germinated. These materials deflect much of the aphids and squash vine borers that fly early in the season. Squash plants can be grown inside the fabric for several weeks and removed or partially opened when flowering begins. Growers can also release beneficial insects like lacewings and lady beetles under the fabric for controlling accidental pest infestations.

    For both trap crops and pest exclusion tactics, check out the short IPM videos on the Beginning Farm Project channel at www.youtube.com/playlist?list=PLkNoAmOtt___MKj6IBxvWzOdWP0btBq4D.

    INSECTICIDE USE
    Growers also have a wide range of organic insecticides to choose from (Level 3 control). See the Organic Materials Review Institute website (www.omri.org) to find hundreds of approved organic products.

    Remember to scout squash crops for timely pest detection and identification, then use insecticides per the label with equipment that gives good coverage. For example, highly mobile squash bug adults are difficult to control with natural pyrethrin and spinosad, but the flightless small nymphs are far better targets for organic spray applications.

    Several premix insecticides are available commercially today in a variety of packaging, making them affordable for farmers. Squash vine borer and pickleworm larvae are internal pests, which are difficult to manage with topical spray applications. Initiate timely sprays with targeted placement where insect pests are hidden.

    Don’t quit spraying too soon since weather patterns can reduce insecticide persistence. Always spray in the evening hours when bees are not around and so that the solution can dry out overnight. Stop spray applications of organic materials when pests become inactive. You can save on the cost of insecticides and protect natural enemies this way.

    Finally, it is recommended that growers get in touch with Extension personnel in their state to develop an IPM strategy suitable for their farm. Producers in Alabama can download the Farming Basics mobile app to keep in touch with Alabama Extension. Subscribe to the Alabama IPM Communicator e-newsletter (www.aces.edu/ipmcommunicator) to stay informed throughout the season.

    Ayanava Majumdar is an Extension professor and Rammohan Balusu is a research fellow, both at Auburn University. Neil Kelly is a regional Extension agent with the Alabama Cooperative Extension System.

    This story was from the July edition of VSCNews Magazine. To subscribe, see http://vscnews.com/subscribe/.

  • Technology to Improve Vegetable Production

    Initial design of the low-cost robotic sprayer for precision weed control in vegetable production: main components of the smart sprayer (A) and self-reconfigured and self-adjustable design for easy field deployment in a variety of vegetable fields (B).

    By Yiannis Ampatzidis

    Vegetable growers face a variety of challenges, including pest and diseases, labor shortages and climate change. How can new advancements in technology help growers address these challenges? Can technology improve crops, reduce production costs and protect the environment? How can technological innovations be incorporated into traditional farming to improve production practices?

    In the last few decades, several “smart” technologies have been developed for vegetable production and processing. However, growers are confronted with a variety of challenges when considering adopting new technology or adjusting existing technology. Growers are being offered solutions that might not work in their specific production system or might not be economically feasible. This article presents examples of state-of-the-art technologies that may be used in vegetable production today or in the near future!

    SIMPLIFY SURVEYING
    Field surveys for disease/pest scouting and to assess plant stress are expensive, labor intensive and time consuming. Since labor shortage is a major issue in vegetable production, small unmanned aerial vehicles (UAVs) equipped with various sensors (remote sensing) can simplify surveying procedures, reduce the labor cost, decrease data collection time and produce critical and practical information.

    For example, recently UAVs and remote sensing have allowed growers to constantly monitor crop health status, estimate plant water needs and even detect diseases. The precision agriculture team (@PrecAgSWFREC) at the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) Southwest Florida Research and Education Center (SWFREC) developed a cloud-based application called Agroview (http://agroview.farm/login.php).

    Agroview can process, analyze and visualize data collected from UAVs and other aerial platforms (e.g., small planes and satellites). This technology utilizes machine learning (an application of artificial intelligence) to detect single plants and assess plant size and stress. Agroview and UAVs were initially used to create plant inventories in citrus (see a video demonstration at https://twitter.com/i/status/1202671242647490560) and to detect specific diseases in vegetables with high accuracy. Early detection and eradication of infected plants is crucial to controlling disease and pest spread throughout the field.

    SMART SPRAYERS

    Most conventional sprayers apply agrochemicals uniformly, even though distribution of pests and diseases is typically patchy, resulting in waste of valuable compounds, increased costs, crop damage risk, pest resistance to chemicals, environmental pollution and contamination of products. Contamination can be related to run-off after application, discharge from drainage and off-target deposition of spray due to wind (spray drift). This contamination can be significantly reduced through optimization of spraying technology.

    Spray drift of agrochemicals occurs during every application and accounts for a loss of up to 50 percent of the agrochemical used. Minimizing the negative impacts of agrochemicals (and spraying technologies) is a major global challenge.

    More than 90 percent of the acreage of crops in the United States are being sprayed with herbicides. It is estimated that $26 billion is spent on herbicides (more than 3 billion pounds) each year. This overuse of chemicals creates herbicide-tolerant weeds and approximately 250 known species of resistant weeds.

    In recent decades, several smart technologies have been developed for pest detection and for optimizing spraying applications. These new spraying technologies have shown an important improvement in efficiency and safety by adopting the latest advances in electronics, artificial intelligence (AI) and automation.

    One example is the See & Spray machine developed by Blue River Technology (www.bluerivertechnology.com) for weed control in arable crops. See & Spray utilizes computer vision and AI to detect and identify individual plants (such as cotton) and weeds and then applies herbicide only to the weeds. See how this technology works at https://youtu.be/gszOT6NQbF8. This machine can reduce the required quantity of herbicide by more than 90 percent compared to traditional broadcast sprayers. However, this technology was designed for arable crops and might not be a cost-effective solution for specific vegetable production systems.

    Another low-cost smart sprayer has been designed and developed by the UF/IFAS team for precision weed management in vegetables. In the initial evaluation experiments, smart technology was able to accurately detect and distinguish weeds from crops and apply chemicals only on specific weed(s), thus avoiding crops and areas without weeds. See a video demonstration of this technology at https://twitter.com/i/status/1045013127593644032.

    Recently, the precision ag team, in collaboration with Abhisesh Silwal (Carnegie Mellon University) and Panos Pardalos (UF), received funding from the U.S. Department of Agriculture and the National Research Foundation (award #2020-67021-30761) to improve and fully automate this smart sprayer. This novel robotic sprayer (or fleet of sprayers) was designed to be self-reconfigured and self-adjustable for easy field deployment (Figure 1). With this design, the robot can reconfigure itself (Figure 1b) to manage weeds in a variety of vegetable fields (e.g., with different row spacing and raised bed sizes).

    ROBOTIC HARVESTING

    Fresh-market vegetables are quickly perishable and virtually 100 percent are hand-harvested. Vegetable growers face increasing shortages of laborers, which in turn, drive up harvest costs. Mechanical and robotic harvesting systems for vegetable growers could simultaneously decrease their dependence on manual labor, reduce harvesting costs and improve overall competitiveness in the market.

    In one example, Harvest Croo Robotics, a Florida company, is developing a robotic harvester for strawberries that does not require growers to radically change the way they currently grow crops. This technology successfully harvested berries during the 2019–20 season. It could address the labor shortage problem and increase grower profit. 

    Yiannis Ampatzidis (i.ampatzidis@ufl.edu) is an assistant professor at the UF/IFAS SWFREC in Immokalee, Florida.

    This story was from the July edition of VSCNews Magazine. To subscribe, see http://vscnews.com/subscribe/.

  • Sneak Peek: August 2020 VSCNews Magazine

    By Ashley Robinson

    The August issue of VSCNews magazine equips growers with the latest information and strategies to develop a sound fumigation system.

    With the loss of methyl bromide, many growers have struggled to maintain consistent soilborne pathogen and pest control with fumigants that are currently available. Gary Vallad, Johan Desaeger, Joe Noling and Nathan Boyd of the University of Florida Institute of Food and Agricultural Sciences (UF/IFAS) discuss supplemental fumigation strategies for tomato production.

    In 2018, a comprehensive survey identified root-knot nematodes as the top nematode pest among Georgia vegetable crops. Abolfazl Hajihassani, an assistant professor and Extension specialist and Chinaza Nnamdi, a plant pathology graduate student, both at the University of Georgia (UGA) in Tifton, share proper management practices to successfully control these pests.

    Anthracnose fruit rot disease is one of the most significant disease problems of commercial strawberry production in the Southeast. To control the disease, growers have typically relied on preventive fungicide applications, the most commonly used fungicide being quinone outside inhibitors (QoIs). However, growers have recently noticed a resistance to QoIs. Phil Brannen, Emran Ali, Jeff Cook, Sumyya Waliullah and Owen Hudson, all at UGA, present new recommendations and strategies for growers struggling with fungicide resistance.

    Desaeger, an assistant professor for UF/IFAS is back for another article in this month’s issue. This time, discussing Florida’s up and coming hemp crop. With an increased interest in hemp, researchers are investigating how nematodes may affect this new Florida crop.

    Additionally, Jenelle Patterson, a plant molecular biologist, shares how bioengineered sentinel plants could help protect future crops.

    Finally, it’s Expo time! Even though coronavirus has prevented growers from gathering in person for the Vegetable and Specialty Crop Expo, the virtual event will continue to provide growers with the great education they need. On Aug. 19–20, the seminar program will go online at VSCExpo.com, and growers can tune in and watch the seminar presentations from the comfort of their own home. Those who watch the seminars when they debut online will be eligible to win door prizes, including four $200 Bass Pro gift cards.

    There is no charge to attend the virtual Expo, but registration is required to view the seminar videos. Keep up to date on all the latest event information and register to attend at VSCExpo.com.

    If you would like to receive future issues of VSCNews magazine, click here.

  • Organic management methods for squash pests

    A squash bug lays its eggs in a crop.

    By Ayanava Majumdar, Rammohan Balusu and Neil Kelly

    Many pests feed on squash from seedling to harvest. They are generally broken down into two groups: the chewing insects and the sucking insects. Chewing insects of squash consist of common pests like cucumber beetle, squash vine borer larva and pickleworm. Sucking insect pests consist of aphids, squash bugs and whiteflies. The pests a squash grower experiences may depend on location.

    PREVENTION STRATEGIES

    Remember that prevention of pests is the No. 1 goal of organic integrated pest management (IPM) systems. Rapid control after pest establishment becomes a difficult aim later in the production season. Cultural control tactics that include selecting virus-resistant varieties, timely planting and harvest (reduces pickleworm buildup), crop rotation and timely removal of crop debris after harvest (reduces squash vine borer buildup), consistent irrigation and trap cropping are some basic preventive approaches, also called Level 1 control.

    Perimeter trap cropping with Baby Blue and New England Hubbard squash in a mixed system is effective in reducing cucumber beetle and squash bug damage to yellow squash (main crop).

    PEST EXCLUSION FABRIC

    For Level 2 control, growers should use temporary or permanent pest exclusion fabric to create a barrier between insect pests and the main crop. Two lightweight materials tested in Alabama include the Super-Lite Insect Barrier (Gardens Alive, Inc.) and AgroFabric Pro 19 (Seven Springs Farm, Inc.). Both these materials look like lighter versions of the common row cover used for frost protection, but these materials are much lighter with 85 to 95 percent light and rain penetration.

    The trick is to put these light fabrics on low hoops (inverted loops) almost immediately after transplanting or after the seeds have germinated. These materials deflect much of the aphids and squash vine borers that fly early in the season. Squash plants can be grown inside the fabric for several weeks and removed or partially opened when flowering begins. Growers can also release beneficial insects like lacewings and lady beetles under the fabric for controlling accidental pest infestations.

    For both trap crops and pest exclusion tactics, check out the short IPM videos on the Beginning Farm Project channel at www.youtube.com/playlist?list=PLkNoAmOtt___MKj6IBxvWzOdWP0btBq4D.

    INSECTICIDE USE

    Growers also have a wide range of organic insecticides to choose from (Level 3 control). See the Organic Materials Review Institute website (www.omri.org) to find hundreds of approved organic products.

    Remember to scout squash crops for timely pest detection and identification, then use insecticides per the label with equipment that gives good coverage. For example, highly mobile squash bug adults are difficult to control with natural pyrethrin and spinosad, but the flightless small nymphs are far better targets for organic spray applications.

    Several premix insecticides are available commercially today in a variety of packaging, making them affordable for farmers. Squash vine borer and pickleworm larvae are internal pests, which are difficult to manage with topical spray applications. Initiate timely sprays with targeted placement where insect pests are hidden.

    Don’t quit spraying too soon since weather patterns can reduce insecticide persistence. Always spray in the evening hours when bees are not around and so that the solution can dry out overnight. Stop spray applications of organic materials when pests become inactive. You can save on the cost of insecticides and protect natural enemies this way.

    Finally, it is recommended that growers get in touch with Extension personnel in their state to develop an IPM strategy suitable for their farm. Producers in Alabama can download the Farming Basics mobile app to keep in touch with Alabama Extension. Subscribe to the Alabama IPM Communicator e-newsletter (www.aces.edu/ipmcommunicator) to stay informed throughout the season.