Harvest And Postharvest Techniques To Prevent Bacterial Soft Rot

Bacterial Soft Rot

Producing a healthy crop obviously is of the utmost importance to vegetable growers, and among the key factors necessary to get quality produce to market is the care taken from harvest to packing.

One problem experienced by growers of tomatoes, potatoes, and others is the postharvest attack of the bacterium Erwinia sp., known otherwise as bacterial soft rot. Soft rot can become a serious issue, particularly when care is not taken to prevent bruising, etc. during harvest and proper postharvest food safety practices are not adhered to in packing areas.
In addition to proper postharvest handling, having the adequate levels of nutrients in the plants while they are growing in the field — especially calcium — is important for reducing the effects of this bacteria. It is reported that in warm, humid climates, bacteria can affect the inside of stems and the epidermis.

One of the first crops attacked by bacterial soft rot is tomatoes. Four species of bacteria are known to cause infection. In addition to tomatoes, the bacterium has been reported on other crops as well, such as potatoes, peppers, carrot, lettuce, cabbage, and onion.

Soft Rot Symptoms

Many symptoms will help growers identify soft rot in their fields. Specifically, infected fruit show soft, odiferous lesions. The spots are small, sunken areas that are watery in appearance. These injuries range from a light to slightly darker color and are related to the natural openings or wounds in the fruit. There may be a characteristic discharge coming from the wound that is made up of millions of bacteria.

Erwinia can affect roots and stems, causing darkening of the tissues. The bacteria in potatoes is called blackleg, and can cause plant death.

Survival Of The Pathogens

What makes soft rot critical to control is that bacteria can survive on vegetables in various parts of the plants and also has the ability to live in low populations in the soil and water.

It is important to note that this strain cannot penetrate the plant; it
can only enter through a previously sustained wound or natural opening in the tissues. During handling, if bruises and wounds occur, and if the water is not disinfected well, the pathogens can enter the fruit.

In potatoes, the main source of inoculum is from the seed tuber, machinery that has been in the field, and irrigation water. The bacteria is active when conditions are favorable for pathogen growth and development — excess moisture, poor aeration, damaged tissues, and a high presence of inoculum.

Leave a Reply

2 comments on “Harvest And Postharvest Techniques To Prevent Bacterial Soft Rot

  1. No company has a single “silver bullet” to eliminate plant and human health pathogens on fruits and vegetables; however, growers and packers armed with a “silver clip” can successfully control pathogens and produce a quality product. Years ago this process was call the Hurdle Approach. I am pleased to find in this article the mention of potential cross contamination from irrigation water and farming equipment. One of the first hurdles to be considered prior to planting is treating the soil to control soil pathogens. A second hurdle is to treat irrigation water. The third hurdle should be to clean and sanitize filed equipment and transportation vehicles to prevent cross contamination from field to field and field to packing house. Once produce enters the packing house there are a number of antimicrobial hurdles to consider. For example, hydro coolers, wash tanks, spray bars and fogging units can be antimicrobial hurdles. A final hurdle that grower and packers cannot control is the consumer washing the produce prior to use. Field to fork hurdles are necessary to assure high quality and safe vegetables. Russell

Featured Stories

CucurbitsFight Phytophthora Blight Of Cucurbits
October 25, 2014
Learn how to identify, the survival and spread, as well as management methods for this disease. Read More
Varieties & RootstocksPlaying The Citrus Rootstock Market Has Risks And Rewards
October 24, 2014
Experimental material forcing producers to roll the dice. Read More
GrapesNorthern Grapes Project Receives $2.6 Million USDA Grant
October 24, 2014
Funds will help complete final two years of multistate effort. Read More
VegetablesEnza Zaden Field Day Highlights 25 Vegetable Varieties [Slideshow]
October 24, 2014
Seed breeder Enza Zaden hosted its 2014 variety showcase September 25th at the company’s research station in San Juan Bautista, California, with 250 Read More
Disease ControlWashington Concord Grape Growers Wrestle With Blackleaf
October 23, 2014
Physiological disorder manifested due to unusually hot and sunny summer. Read More
More Vegetables7 Green Bean Varieties Geared For Florida Growers
October 23, 2014
Leading vegetable seed companies highlight several high-performance selections for producers in the Sunshine State. Read More
MarketingTomato Survey Tracks Consumer Trends
October 23, 2014
Results indicate how labeling matters in purchasing decisions. Read More
CitrusFlorida Citrus Growers Get Box Tax Relief
October 23, 2014
Citrus Commission votes to put dollars back in producers’ hands to spur reinvestment. Read More
Farm ManagementBill Gates Uploading Lots Of Florida Farmland
October 22, 2014
Recent acquisition for the Microsoft icon involves more than 4,500 acres for nearly $28 million. Read More
GenNext GrowersRegister Now For The GenNext Growers Webcast
October 22, 2014
In the first installment of the GenNext Webcast Series, you will learn how to engage with lawmakers and ag associations to help shape a better future for your business and for agriculture. Read More

The Latest

CucurbitsFight Phytophthora Blight Of Cucurbits
October 25, 2014
Learn how to identify, the survival and spread, as well as management methods for this disease. Read More
Varieties & RootstocksPlaying The Citrus Rootstock Market Has Risks And Rewar…
October 24, 2014
Experimental material forcing producers to roll the dice. Read More
GrapesNorthern Grapes Project Receives $2.6 Million USDA Gran…
October 24, 2014
Funds will help complete final two years of multistate effort. Read More
VegetablesEnza Zaden Field Day Highlights 25 Vegetable Varieties …
October 24, 2014
Seed breeder Enza Zaden hosted its 2014 variety showcase September 25th at the company’s research station in San Juan Bautista, California, with 250 Read More
Disease ControlWashington Concord Grape Growers Wrestle With Blackleaf
October 23, 2014
Physiological disorder manifested due to unusually hot and sunny summer. Read More
More Vegetables7 Green Bean Varieties Geared For Florida Growers
October 23, 2014
Leading vegetable seed companies highlight several high-performance selections for producers in the Sunshine State. Read More
MarketingTomato Survey Tracks Consumer Trends
October 23, 2014
Results indicate how labeling matters in purchasing decisions. Read More
CitrusFlorida Citrus Growers Get Box Tax Relief
October 23, 2014
Citrus Commission votes to put dollars back in producers’ hands to spur reinvestment. Read More
Farm ManagementBill Gates Uploading Lots Of Florida Farmland
October 22, 2014
Recent acquisition for the Microsoft icon involves more than 4,500 acres for nearly $28 million. Read More
GenNext GrowersRegister Now For The GenNext Growers Webcast
October 22, 2014
In the first installment of the GenNext Webcast Series, you will learn how to engage with lawmakers and ag associations to help shape a better future for your business and for agriculture. Read More
FruitsAnnual Santa Maria Strawberry Meeting Approaching
October 22, 2014
The meeting will focus on IPM practices, weed management, updates on fumigation, and more. Read More
Apples & PearsUSApple’s AppletizeMe Personality Quiz Help Consumers…
October 22, 2014
Award-winning national apple month campaign returns with more featured varieties and informative videos. Read More
Farm ManagementUSDA Awards $18 Million To Stimulate Research And Devel…
October 22, 2014
The grants will provide resources to help small operations create breakthroughs, says USDA Secretary Tom Vilsack. Read More
CitrusEPA Launches Program To Reduce Pesticide Drift
October 22, 2014
The voluntary star-rating program aims to protect people, wildlife and the environment. Read More
CitrusMcCrometer Introduces New Ag Management Mobile App
October 22, 2014
The app displays data on weather, ET, soil moisture, water flow, and more. Read More
Apples & PearsNew York Apple Growers Partner With Grocer To Introduce…
October 22, 2014
First apples of this new variety to hit Wegmans stores as part of a marketing effort. Read More
CitrusAgriculture, Interior Departments Partner To Measure Co…
October 22, 2014
Goal is to provide science-based information for watershed wellness. Read More
Stone FruitIntroducing A Gem Of A Peach For Central Florida
October 22, 2014
The newest variety to come from the UF Stone Fruit Breeding Program is another “gem,” UFGem! This peach variety is Read More