NUTRITIONAL QUALITY OF PHASEOLIN TYPES AND MORPHOTYPES OF GREEN BEAN (Phaseolus vulgaris L.)

The long tradition of green bean (Phaseolus vulgaris L.) cultivation in Croatia has resulted in the development of a landraces adapted to specific areas and chosen to suit different dietary habits. The hypothesis of our study was that nutritional quality (content of proteins, sugars, fibres, calcium, potassium and phosphorus in fresh pods) of 14 widely grown Croatian green bean accessions is affected by origin and morphotype. The analysed accessions were grown in non-replicated field plots where morphotypes were classified. The gene pool of adscription (Andean vs. Mesoamerican) of each accession was determined with the phaseolin marker, whereas nutritional quality traits were analysed according to standard analytical methods. The relationships among nutritional quality traits of fresh pods were assessed by Pearson's correlation coefficient. The univariate ANOVA and a post hoc Tukey test (p <= 0.05) were carried out for each trait to compare the values among accessions. Accessions were grouped according to phaseolin type (I, II or III) and morphological traits (growth habit, pod colour and width). Four accessions had phaseolin type I ("S") predominant in the Mesoamerican while the rest of accessions belong to the Andean gene pool characterized by the phaseolin type II ("H" or "C") or III ("T"). Significant differences among accessions grouped by phaseolin type were found in all nutritional quality traits. The accessions of the Mesoamerican gene pool had higher dry matter content and crude protein content of fresh pods, while those of the Andean gene pool had higher total sugars content. Accessions of indeterminate growth habit had higher dry matter and crude protein content as well as phosphorus and potassium content than determinate ones, but display lower total sugar and calcium content. Outstanding accessions: S538, S541, S506 and S545 could be used as valuable sources of bioactive nutrients in future breeding programs.