Hazelnut phenological phases and environmental effects in two central Italy areas

Abstract

Hazelnut trees, were investigated in central Italy to study their biology and relationships with principal environmental variables. The cyclical repetition of seasonal development in plants may be sensitive to meteorological variation, making phenology of particular interest for studying the climate change effects on vegetative development using new standardization techniques for observing and interpreting the growth of different plant species. Plants of Corylus avellana L. planted in phenological gardens in central Italy areas were examined to analyse the phenology of their growth stages in relation to different climate characteristics. Phenological observations following the guidelines of the International Phenological Gardens network were carried out during a 13-year period. Temperature and solar radiation showed the highest homogeneity among the different vegetative phases in both of the study areas, while other meteorological variables (Precipitation and RH) were heterogeneous also considering the particular water table levels present in one of the two observation areas. Two periods (“first leaf development” (FLD) and “leaf presence period” (LPP)) were considered to study the influence of meteorological variables on plant development during important vegetative periods. A certain shortening of the first period was attributed to the delay in bud swelling beginning during the study period. In contrast, a lengthening of the LPP, was related to the progressive delay in the senescence phase.