Morphological properties of fruit bearing shoots of apricot cultivars

Abstract

Morphological properties of fruit bearing shoots: length, number of flower buds and vegetative buds and their ratio were studied in 20 apricot cultivars during a two-year period. Control cultivar for comparison was ?Hungarian Best? (?Magyar kajszi?), clone 235. Fruit bearing shoots of apricot were classified into three groups: shoots, sylleptic shoots and spurs. The average length of shoots ranged from 68.8 to 85.0 cm; of sylleptic shoots from 6.9 to 27.0 cm; and of spurs from 1.4 to 4.1 cm. Flower buds/vegetative buds ratio was higher in spurs and sylleptic shoots (2,5 on average), compared to shoots (1,8 on average). Most of the studied apricot cultivars are characterized by higher flower bud density compared to control cultivar (?Hungarian Best?), indicating their higher yield potential. For all studied traits statistically significant differences between cultivars were found. The great variability was found in length of shoots, number of flower buds, and number of vegetative buds, while small coefficients of variation were found in thickness of shoots and length of internodes. Based on the obtained results, recommendations for pruning can be made. Cultivars with a higher number of flower buds (per 1 m in length and in relation to vegetative buds) such as: ?Lenova?, ?Tomcot?, ?Veecot?, ?Ninfa?, ?Sophia?, ?Silvercot? and ?Goldrich? require severe pruning. On the other hand, cultivars with lower flower bud density e.g. ?Hungarian Best?, ?Cegledy Arany? and ?Bella d?Imola? can be pruned slightly.