Suwannee Valley Watermelon Institute – November 29

Suwannee Valley Watermelon Institute – November 29

Join UF/IFAS Extension for the 2018 Suwannee Valley Watermelon Institute to be held on Thursday, November 29th at the Straughn IFAS Extension Professional Development Center (2142 Shealy Drive Gainesville, FL 32611).  For anyone that grows watermelon or cucurbits, this day-long event will be worth the drive to Gainesville.

The optional morning session will provide an in-depth review of Florida’s watermelon diseases (bacteria and virus, etc.) with focus on detection and management of new diseases, and an update on drone research for early disease and other stress detection.

After lunch, the following topics will be covered:

  • Irrigation and nutrient management BMPs for the Suwannee Valley Region and Cost Share Programs
  • Watermelon grower experiences with soil moisture sensors
  • Weed management updates, nutsedge, and brunswick grass concerns
  • Update on the Food Safety Modernization Act and new guidance on water and update regarding On-Farm Readiness review process.
  • Watermelon cultivar and fusarium trial results, and review of pollinating plant choices.
  • Watermelon disease and fungicide program planning for the 2019 season.

For more information, contact Dan Fenneman at (850) 973-4138 or by email at dfenneman@ufl.edu.

Fig. 1. Symptoms of the Pseudomonas syringae leaf spot on watermelon

Brown Marmorated Stink Bug Control Using Natural Enemies

Brown Marmorated Stink Bug Control Using Natural Enemies

A few weeks ago I was lucky enough to attend North Carolina State’s Tomato Field Day, at the Mountain Horticultural Crops Research and Extension Center in Mills River, NC.  Every summer crowds flock from all over the Southeast to learn what’s new in the world of tomatoes.  Since it’s not always convenient for you to drop what you’re doing to make a road trip to North Carolina, I’ll highlight something I learned from the field day.

Stink Bug Control by Dr. Jim Walgenbach

Distribution

The brown marmorated stink bug (BMSB) was introduced into the United States from Asia.  The insect pest was first found in Pennsylvania and is suspected to have made its way to the US in packing material.  BMSB was first reported in 2009 in Hillsborough County, FL and since been found in additional Florida counties.  It has a wide host range including fruits, vegetables, and ornamentals.

Fifth instar nymph of the brown marmorated stink bug

Fifth instar nymph of the brown marmorated stink bug on raspberry in Allentown, Pennsylvania.  Photo Credit: Gary Bernon, USDA-APHIS

Identification

BMSB has a typical stink bug body shape and size with a mottled brown coloring.  The key identification feature is alternating dark and light bands on the last two antennal segments.

Trissolcus japonicus adults.

Trissolcus japonicus adults. Female to the left; male to the right. Photo Credit: FDACS – DPI

Biological Control with Natural Enemies

Dr. Walgenbach’s team is currently researching the impact of suppressing BMSB populations by native predators such as: katydids; jumping spiders; earwigs; and lady beetles.  Current observations indicate only a minor effect from these predators on BMSB.

Parasitized BMSB

BMSB egg masses parasitized by T. japonicus. Photo Credit: Matt Lollar, University of Florida/IFAS Extension.

Trissolcus japonicus Assessment

A regional effort has been implemented to monitor the introduction, spread, and efficacy of the Asian parasitoid Trissolcus japonicus.  Trissolcus japonicus is a tiny wasp that parasitizes the eggs of various stink bug species.  It was first collected from China and brought back to quarantine facilities in the US for evaluation, as a potential biological control agent.  Host-specific tests have indicated that T. japonicus prefers to parasitize BMSB eggs over eggs of other stink bug species.  It is suspected that release permits for the wasp will be available from the USDA in the near future.

Reporting in Florida

The brown marmorated stink bug overwinters in homes to keep warm.  If stink bugs are found in yuor home, they may be the BMSB and should be reported to the Florida Department of Agriculture and Consumer Services Division of Plant Industry.  Specimens should be collected for identification.

To follow the research of Dr. Walgenbach and his colleagues, please visit NC State’s Entomology webpage.

Friday Feature:  Flexnet Drip Irrigation System

Friday Feature: Flexnet Drip Irrigation System

This week’s featured video was produced by Netafim to introduce their FlexNet™ drip irrigation system.  Unlike traditional layflat tubing systems that must be pierced for drip-line tubing attachment, their FlextNet plastic tubing has built in connectors to prevent leaks at the hose source. These connectors can be customized to match a farmers specific row spacing from 12-40″.  This innovative irrigation system could be useful for irrigation of vegetables, cucurbits, or other crops with drip irrigation in the row beds.

According to the FlexNet™ website, this system offers the following advantages over traditional layflat systems:

  • Quick Assembly
    Integral welded connectors ensure a secure, leak-proof connection between distribution pipes and laterals (with no teflon or glue required when using Netafim fittings)
  • Agro-Machinery Friendly
    When not pressurized, it’s so durable it can be stepped on or driven over
  • Low Expansion Rate
    Pipe lays flat, has zero axial elongation and will not tangle or bend

FlexNet is simple, flexible and light-weight for maximum portability and quicker movement from field to field. It can be used in surface or subsurface applications and requires no specialized tools for installation.

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If you enjoyed this video, you might want to check out the featured videos from previous weeks:  Friday Features

If you come across an interesting or humorous video, or a new product innovation related to agriculture, please send in a link, so we can share it with our readers. Send video links to:  Doug Mayo

 

Cautious Optimism About Whitefly Pressure on Fall Vegetables this Year

Cautious Optimism About Whitefly Pressure on Fall Vegetables this Year

Figure 1.  Cucurbit Leaf Crumple (CLC) Credit: Josh Freeman, UF/IFAS

Tomato Yellow Leaf Curl (TYLC) Credit: Josh Freeman, UF/IFAS

Josh Freeman, Associate Professor of Horticultural Sciences, University of Florida, Xavier Martini, Assistant Professor of Entomology, University of Florida, Mathews Paret, Associate Professor of Plant Pathology, University of Florida, Stormy Sparks, Professor of Entomology, University of Georgia, and Bhabesh Dutta, Assistant Professor of Plant Pathology, University of Georgia

Vegetable farmers have vivid memories of the disaster that was the fall 2017 vegetable growing season, with Biblical proportions of whiteflies and nearly 100% virus infection. Cucurbit and tomato producers saw catastrophic losses to Cucurbit Leaf Crumple (CLC)  (Figure 1) and Tomato Yellow Leaf Curl (TYLC) (Figure 2), respectively, and both groups invested tremendous resources attempting to control whiteflies that often infested crops within minutes of transplanting.

The 2017 growing season built on problems that started during the fall of 2016. Many agree that the mild winter allowed whiteflies to overwinter in our area on alternative hosts that would have normally been killed by freeze events. We were fortunate in our area to have 18 freeze events between December 15, 2017 and February 15, 2018. Eight of these events were below 25°F (FAWN data from the Quincy station).

This brings us to June 2018. Researchers have set up whitefly traps in North Florida, and South Georgia, but none have been caught in recent weeks.  There were two weeks in April when whiteflies were found in tomato fields, but none have been reported since. It appears that whitefly populations did not overwinter in our area in significant numbers. If it sounds like I’m being cagey with my wording it’s because I am. With populations like we saw last year I’m exceptionally hesitant to say we’re out of the woods yet, but it appears whitefly populations are on track for a normal year. And by normal I mean that our populations will ramp up to numbers that need to be managed by October, hopefully near the end of most crops. I personally believe that it will be sooner than that, and I expect they will need to be managed in September, again just an educated guess. But don’t stop reading the article just yet.

As of June 5, 2018 there have been multiple positive tests for Cucurbit Leaf Crumple (CLC) in watermelon in the area, and at least one positive test for Tomato Yellow Leaf Curl (TYLC), despite few whitefly numbers being found in the spring growing season. For tomato producers I still have tremendous concerns about TYLC infestation in fall crops and serious yield loss that could be sustained. The reason I concentrate on TYLCV is that we have resistant, not immune, varieties to combat this disease. During fall 2016 TYLC incidence increased later in the season, but still caused significant yield depression. In fall 2017, whitefly pressure was extreme during most of the season and varieties not resistant to TYLCV had 100% infection by the second tie.  See the results of the Fall 2016 NFREC tomato variety trial and the Fall 2017 NFREC tomato variety trial conducted in Quincy to see the full comparison of varieties. Additional information on resistant varieties can be found in the tomato production chapter of the Vegetable Production Handbook of Florida. Resistant varieties are available that will protect producers against losses from TYLCV and I recommend using these resistant varieties for fall 2018 production. In my opinion the risk of loss from TYLCV outweighs unfamiliarity with producing resistant varieties. Even if resistant varieties are used it is still critical to manage whiteflies because feeding can result in irregular ripening in tomato.

Cucurbit producers unfortunately don’t have as many options for managing whitefly transmitted viruses because there are no commercially available squash, cucumber, cantaloupe, or watermelon varieties with resistant to CLC. Because of this I think that fall cucurbit production, especially late season crops could be quite risky this year.

Regardless of whether it’s a cucurbit or tomato crop this fall, it is recommended that producers take all the usual steps to manage whiteflies. These management tactics can be found in the following publications.  If you find whiteflies or suspected virus in your spring or early fall crops please notify your local extension agent because we would like to keep track of these for future reference.

Management of Whiteflies, Whitefly-Vectored Plant Virus, and Insecticide Resistance for Vegetable Production in Southern Florida

Recommendations for Management of Whiteflies, Whitefly-Transmitted Viruses, and Insecticide Resistance for Production of Cucurbit Crops in Florida

 

Friday Feature:  Melon Planting Equipment Demonstration

Friday Feature: Melon Planting Equipment Demonstration

This week’s featured video was produced by a member of the Panhandle Ag Extension Team, Matt Lollar, now located in Santa Rosa County.  Locally grown cantaloupes are being harvested now and are available at your local farmer’s market or grocery store.  See how they got their start in this video.  The video was filmed at Forrester Farms, in Jackson County.

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If you enjoyed this video, you might want to check out the featured videos from previous weeks:  Friday Features

If you come across an interesting or humorous video, or a new product innovation related to agriculture, please send in a link, so we can share it with our readers. Send video links to:  Doug Mayo

Water Source Recommendations for Food Safety

Water Source Recommendations for Food Safety

Supplemental water is necessary for good crop yields in fruit and vegetable production. Water quality is equally as important as water quantity when it comes to fruit and vegetable production. Unfortunately, water can transport harmful microorganisms from adjacent lands or other areas of the farm. The water source and how the water is applied influence the risk for crop contamination to occur.

Water is used for various purposes during production: harvesting, and handling fresh produce, irrigation, cooling, frost protection, as a carrier for fertilizers and pesticides, and for washing tools and harvest containers, hand washing, and drinking.

Washing lettuce. Photo Credit: Cornell University Extension

The FDA’s Food Safety Modernization Act (FSMA) proposed water compliance date is not until 2022, but it will be here before you know it. Water quality is an important component of a Food Safety Plan. A good first step in ensuring compliance with FSMA water quality standards is to evaluate the water sources on the farm.  For more information on compliance dates, please visit the Produce Safety Alliance’s Website.

Water Source

The three common sources of water used on farms are surface water, well water, and municipal water.

Surface water includes ponds, lakes, rivers, and streams. It is at the highest risk for contamination because there is limited control on what flows downstream or from adjacent land. Wild and domestic animals, manure piles, and sewage discharges are all potential sources of contamination in surface waters.

The most common water source for North Florida farms is well water. Well water used for farming is at a moderate risk of becoming contaminated, when compared to surface water (highest risk) and municipal water (lowest risk). Wells are at a higher risk of becoming contaminated when located near flood zones, septic tanks, drainage fields, and manure/compost storage areas. The risk of contamination is further heightened if the well was not constructed properly, or if the casing is cracked. Wells should be properly sited, constructed, and maintained to keep contamination risks lower.

a well pump

A recently installed well pump on a North Florida watermelon farm. Photo Credit: Matt Lollar, University of Florida/IFAS Extension

Well Design and Construction

  • Preliminary Investigation – A preliminary investigation helps determine the design of a well. Existing wells in the area should be checked out to help determine depth and potential capacity. If records for the area aren’t available, then test holes should be drilled to determine the best location for water production.
  • Casing – Casing material should be determined based on site characteristics. The casing needs to extend above the surface water level to reduce contamination risks. The casing is sealed in place with grout. A poor grouting job can also promote contamination. Casing diameter is selected based on well capacity.
  • Well Screen – A commercially designed well screen should be installed to minimize hydraulic head loss. Screen diameter and material should be determined based on the preliminary investigation results. Gravel packing is recommended in some areas.

For more recommendations on well design and construction, please visit the University of Florida/IFAS publication: Design and Construction of Screened Wells for Agricultural Irrigation Systems

Please note that it is important to monitor your well water quality at least twice during each growing season.  A list of FSMA approved water testing methods can be found at Cornell University’s Law School Website.