RELATIONSHIP BETWEEN THE NUTRITION AND THE APPEARANCE OF “GREENBACK” AND “BLOSSOM-END ROT” IN TOMATO FRUITS

Economical plant production of today is not only a problem of yield level but also a problem of satisfactory quality of the marketable products.
Quality in general is still a complex concept.
In tomatoes, fruit colour is an important aspect of quality for the consumer and an essential factor for commercial growers.
There is an increasing demand for round, medium-sized and uniformly coloured fruits of un-objectionable quality.
However, several kinds of colour disorders occur in tomato fruits and these have been the object of numerous studies.

In a small-scale nutrition experiment carried out some time ago tomatoes with typical ripening disorders could be observed in some fruits.
For the tomato growers these are known as "Grünkragen" or in Englisch "greenback". If you cut a tomato fruit with these symptoms, the green or yellow tissue around the calyx is hard and such fruits have no marketing quality.
This first experiment also showed that with increasing K concentrations in the nutrient medium the greenback disappeared.
Therefore in 1970 a second solution experiment was executed in order to solve the question: are there relationships between nutrition, particularly K nutrition and the appearance of "greenback" as well as symptoms of "blossom-end rot"?

Symposium on Nutrition and Fertilization of Vegetables

H. Forster

https://doi.org/10.17660/ActaHortic.1973.29.24