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
IFTA Washington Day3 6
Apples & Pears
May 27, 2016
Washington Apple Commission Elects New Leaders
The commission board also approved the export budget of $7.7 million for the upcoming 2016-17 crop, based on a crop of 135 million cartons. Read More
As this view of the San Luis Reservoir shows, California's drought is far from over. (Photo credit: David Eddy)
Fruits
May 27, 2016
California Drought Far From Over For
To preserve orchards and vineyards, growers are expected to fallow up to 350,000 acres of corn, wheat, cotton and alfalfa. Read More
These workers use a platform from Automated Ag for hand thinning. (Photo credit: Christina Herrick)
Apples & Pears
May 27, 2016
How Best To Integrate Man And Machine
If you want to implement labor-saving mechanization, you should start the conversation with the end user – your employees. Read More
Crowd protesting GMOs stock image FEATURE
Farm Marketing
May 27, 2016
Consumers Don’t Really Know What GMO Means, New Study Finds
A study from the University of Florida confirms what many farm marketers suspected: consumers don't understand genetically modified food and organisms as well as they think they do. In fact, 80% of consumers think food containing DNA should be labeled (almost as many who think GMO food should be labeled). Read More
Asian citrus psyllid closeup
Insect & Disease Update
May 27, 2016
Alabama Agriculture Department To Conduct Citrus Psyllid Survey
Currently, Alabama is the only citrus-growing state that has not yet detected citrus greening. Read More
Ready To Spring
Insect Control
May 26, 2016
Temperature, Location Key To Predicting Leaffooted Bug Pressure
This year, leaffooted bugs are expected to be a significant problem in almonds and pistachios, but watching temperature and the Read More
First-year impact of Prunus replant disease at the Firebaugh replant trial; stunted trees in the foreground row were planted in plot of non-fumigated replant soil. (Photo credit: University of California Agriculture)
Fruits
May 26, 2016
Consider Fumigating For Nematodes Before Replanting Almonds, Stone Fruit
Stone fruit and almond growers looking to replant orchards might want to invest in soil samples to assess nematode populations Read More
An open air farm dinner at Tangletown's farm FEATURE
Farm Marketing
May 26, 2016
Farm Dinners: Your Most Powerful Marketing Tool?
Farm dinners are a hassle. They’re expensive. And ridiculously effective. Read More
Whiteflies on a leaf
Cucurbits
May 25, 2016
Whitefly Threat Has Florida Growers On High Alert
Researchers, state agencies working together to prevent a potential outbreak. Read More
The Latest
Apples & Pears
May 27, 2016
Washington Apple Commission Elects New L…
The commission board also approved the export budget of $7.7 million for the upcoming 2016-17 crop, based on a crop of 135 million cartons. Read More
Fruits
May 27, 2016
California Drought Far From Over For
To preserve orchards and vineyards, growers are expected to fallow up to 350,000 acres of corn, wheat, cotton and alfalfa. Read More
Apples & Pears
May 27, 2016
How Best To Integrate Man And Machine
If you want to implement labor-saving mechanization, you should start the conversation with the end user – your employees. Read More
Farm Marketing
May 27, 2016
Consumers Don’t Really Know What G…
A study from the University of Florida confirms what many farm marketers suspected: consumers don't understand genetically modified food and organisms as well as they think they do. In fact, 80% of consumers think food containing DNA should be labeled (almost as many who think GMO food should be labeled). Read More
Insect & Disease Update
May 27, 2016
Alabama Agriculture Department To Conduc…
Currently, Alabama is the only citrus-growing state that has not yet detected citrus greening. Read More
Insect Control
May 26, 2016
Temperature, Location Key To Predicting …
This year, leaffooted bugs are expected to be a significant problem in almonds and pistachios, but watching temperature and the Read More
Fruits
May 26, 2016
Consider Fumigating For Nematodes Before…
Stone fruit and almond growers looking to replant orchards might want to invest in soil samples to assess nematode populations Read More
Farm Marketing
May 26, 2016
Who Grows Organically — And Who Doesn…
We surveyed 816 fruit and vegetable growers and found that farm marketers and vegetable growers are much more likely than their peers to embrace the practice. Read More
Farm Marketing
May 26, 2016
Farm Dinners: Your Most Powerful Marketi…
Farm dinners are a hassle. They’re expensive. And ridiculously effective. Read More
Cucurbits
May 25, 2016
Whitefly Threat Has Florida Growers On H…
Researchers, state agencies working together to prevent a potential outbreak. Read More
Crop Protection
May 25, 2016
More Apps Help Growers Identify Insects …
Berries, apples, pears, and cherries now rolled into new app series from Clemson University. Read More
Citrus
May 25, 2016
Monsanto Says Bayer Bid ‘Financially Ina…
Proposal cited as undervalued, not able to address financial, regulatory risks. Read More
Stone Fruit
May 25, 2016
Researchers Study Why Cherry Cracking Af…
German researchers studied how water uptake and fruit skin determined a cultivar’s susceptibility to cherry cracking. Read More
Farm Management
May 25, 2016
Report Highlights Benefits Of Trans-Paci…
National Potato Council says report from the International Trade Commission offers the benefits the free trade agreement would offer growers. Read More
Fruits
May 25, 2016
Farm Bureau Says EPA, Army Corps Of Engi…
AFBF told Congress that the Army Corps' novel interpretations of environmental law are threatening farmers in California and other areas of the country. Read More
Citrus
May 25, 2016
NRCS Invests $4.3 Million To Combat Clim…
The Natural Resources Conservation Service in California is committing funds to help farmers and ranchers mitigate the effects of climate change and help to reduce greenhouse gas emissions. Read More
Citrus
May 24, 2016
Panama Canal Expansion To Bring Trade Op…
Agriculture Commissioner Adam Putnam says a confluence of events is putting the state's producers in a good spot to open new markets. Read More
Citrus
May 24, 2016
Social Media Posts On GMOs Falling Flat …
Hopefully, the hysteria the West has perpetuated on genetic engineering will not stifle the potential of moving our production forward enough to help feed a growing global population. Read More
[gravityform id="62" title="false" description="false"]