Articles
QUALITY MODELS IN HORTICULTURE NEED PRODUCT QUALITY: A RARE BUT CHALLENGING FIELD OF EXPLORATION
Especially for ornamentals, some of these aspects will only be evident during use of the product by the consumer.
Models predicting internal quality attributes as a result of growth conditions are rarely found in literature.
Explanatory models for internal quality of cut flowers as result of growth conditions are totally lacking.
Some bottle-necks and challenges to develop simulation models about internal quality attributes of horticultural products, based on cultivation conditions, are discussed with special emphasis on vase life of cut flowers.
A dynamic and deterministic conceptual model to simulate carbohydrate balance and development of lily inflorescence during vase life was developed.
The inflorescence as a system was defined by the state variables: the carbohydrate pool in the stem and the carbohydrate pool, structural biomass and development stage of each floret in the inflorescence.
An additional auxiliary state variable was used to describe whether a floret is alive or dead due to shortage of carbohydrate supply.
An osmotic pool of the petal cells is included which is treated as an independent sink.
Distribution of available carbohydrates among the osmotic and the non osmotic pool was assumed to be proportional to the sink strengths of both pools, defined as the capacity to accumulate carbohydrates under conditions of non-limiting carbohydrate supply.
The water balance of a cut flower is largely influenced by its rehydration ability after harvest.
A great bottle-neck to achieve a model, that predicts the vase life behaviour as result of pre-harvest conditions, is the limited knowledge of the structural, chemical, or physiological basis for differences in this rehydration ability.
The value of modelling vase life behaviour, based on characteristics at harvest, is discussed in light of defining the ‘quality of design’ of a cut flower in terms of quantitative measurable parameters.