NUTRITIONAL STUDY OF AN APPLE ORCHARD AS ENDEMICALLY AFFECTED BY BITTER-PIT

Bitter-pit has been related to nutritional fruit unbalances, particularly to calcium deficiency.
In order to elucidate the nutritional and physiological processes that lead to a development of bitter-pit, a nutritional study of a Golden Smoothee/M9 apple orchard, endemically affected by bitter-pit has been carried out.
An evaluation of bitter-pit incidence at harvest showed that only few apples had symptoms, but following two months under cold storage, more than 80% were affected.
Mineral elements in leaves and fruits were analysed.
As bitter-pit is associated with fruit size, the diameter and fresh and dry weight of fruits were recorded regularly, and the values fitted to sigmoid equation of growth, to calculate final size and maximum fruit growth rate.
In terms of mineral nutrition, Nitrogen relates linearly to calcium and the ratio K/Ca in fruits increases along the season reaching a value of 68 at harvest time.
A good correlation between leaf chlorophyll and fruit soluble carbohydrates was found.

XXV International Horticultural Congress, Part 3: Culture Techniques with Special Emphasis on Environmental Implications, Disease, Pest Control and Integrated Pest Strategies

J. Val, A. Gil, Y. Aznar, E. Monge, A. Blanco

bitter pit, calcium deficiency, apples, plant nutrition

https://doi.org/10.17660/ActaHortic.1998.513.59