UNIT 1: The Definition and Etiology of BER

Objectives
1.  Define Blossom End Rot (BER),
2.  Describe BER visual fruit symptoms in early, middle and late stages,
3.  Identify the etiology of BER,
by correctly answering true/false or multiple choice items.

Content
Blossom-End Rot (BER) is a physiological disorder, not a disease, affecting the quantity of fruit and affecting the quality of fruit.  It is a calcium disorder of vine and tomato cells, with symptoms especially occurring in fruit cells.  These cell walls collapse and die.

Signs and Symptoms  (Click on photo to enlarge)
BER forms at the blossom end of the fruit, away from the vine attachment. BER occurs in young fruit or in ripened fruit.  First sign appears as a dark, water spot on the fruit (see green fruit toward the right).
At it's earliest stage the lesion may be cut away and the remaining fruit is edible.  The second stage is brown and leathery. As it progresses, opportunistic organisms further attack the lesion (presenting a black mold) and the remaining fruit becomes inedible.

The etiology of BER is a calcium deficiency. This calcium deficiency occurs in (1) the soil preparation phase or (2) the care-and-maintenance phase of horticulture.  Thus we group BER as 'soil-preparation-related BER" and 'care-and-maintenance-related BER'.  

Once BER is recognized (at the fruit production stage) the soil cannot be altered.  Alteration would further disturb deficient root structures.  The only method of treating 'soil-related BER' is to prevent the calcium deficiency during soil preparation, by balancing the soil contents.

Practice

1.  Find two symptoms of BER.
2.  Discuss the etiology of BER.
3.  Is BER a disease or a disorder?
4.  For calcium deficient plants, can soil be treated during the growing season?

Activity
Read My Story.  Then determine the following as related to your own tomato-growing experiences.

If you have grown tomatoes previously, did you experience BER?

Did you test/balance soil (the NPK ratio, pH level and soil particles)?

Perhaps you just added a little fertilizer at the time of planting?  

Did you plant without additives, and concentrate on care-and-maintenance?

How would you feel if your care-and-maintenance was consistent, and when fruit appeared it showed BER?

Is soil preparation important for greater success in tomato growing?

Assessment
On a separate sheet of paper, answer True or False, or select the appropriate letter (a, b, c...).  Then check your work using the link below.

T   F   1.  Tomato Blossom End Rot is a physiological disorder.
T   F   2.  It is caused by a calcium deficiency.
T   F   3.  Fruit cell walls become stronger during BER.
T   F   4.  During early fruit BER symptoms portions of the fruit remain edible.
T   F   5.  Soil treatment for calcium deficiencies during fruiting further damages roots. 

6.  Early stage of BER is described as:
     a. Dark water spot on the blossom end of the fruit
     b. Large brown, leathery lesion on the blossom end of the fruit
     c.  Black moldy lesion with collapsing adjacent fruit cells

7.  Middle stage of BER is described as:
     a. Dark water spot on the blossom end of the fruit
     b. Large brown lesion on the blossom end of the fruit
     c.  Black moldy lesion with collapsing adjacent fruit cells

8.  Late stage of BER is described as:
     a. Dark water spot on the blossom end of the fruit
     b. Large brown lesion on the blossom end of the fruit
     c.  Black moldy lesion with collapsing adjacent fruit cells

Link to Answers

References

Proceed to Unit 2

Credits
Image #1 from Ohio State University Extension
Image #2 from Clemson University Department of Horticulture
Image #3 from University of Wisconsin Cooperative Extension

Revised December 3, 2001
Copyright Anne Premont