Flowering of Hazelnut Cultivars From Different Regions Under the Climatic Conditions of Southern Poland

Climate change impacts on phenology and yield of hazelnut in Australia

“…This result is distinctive, because modelling studies performed on herbaceous crops generally project a decrease in simulated aboveground biomass and yield as a consequence of shorter length of the crop cycle (e.g., Anwar et al, 2015;Bregaglio et al, 2017). The advancement of bud break and start of ovary growth is related to the temperature increase projected by climate models, and is supported by previous studies (Asseng et al, 2015;Piskornik et al, 2001). On the other hand, there are some regions, such as central Australia, where the number of days required to meet these vegetative stages is expected to be delayed.…”

The response of Corylus avellana L. phenology to rising temperature in north-eastern Slovenia

“…Because of the different temperature responses of hazelnut cultivars (Piskornik et al 2001), and also of male and female flowers of the same cultivar, such as 2.3 days for 1°C with 'TGDL' as shown by our research, greater temperature changes in the future could lead to decreased synchrony between the maturation of male and female flowers and increasing incompatibility among cultivars in terms of pollination. The phenomenon of cross-compatibility in hazelnuts has great economic importance (Turcu et al 2001) and could have an even greater future impact.…”

“…Bastias and Grau (2005) concluded that, for some commercial hazelnut cultivars in Chile, the dichogamy phenomenon was not totally dependent on the genotype but also on local climatic conditions. Piskornik et al (2001) showed in their study, in the climatic conditions of southern Poland, that some hazelnut genotypes were protandrous after long and severe winters, homogamous after short but cold winters, and protogynous when winters were short and relatively mild. In our case, mild winters could also be the reason for changed dichogamy during P2 for 'Gunslebert' and 'Bollwiller'.…”

“…requires only a very short period of heat accumulation after vernalisation and there are differences in post-rest heat requirements among genotypes with the same estimated chilling requirement (Mehlenbacher 1991). Hazelnut flowering time varies greatly according to the climate and is very temperature-dependent; it thus varies greatly from year to year (Piskornik et al 2001). Trees grown in mild regions may flower for months while trees in cold regions for only for a few weeks.…”

Dynamics of flowering of male and female inflorescence and pollen germination of hazel in the conditions of the Banja Luka region

“…Dichogamy occurs during the period of flowering. Protandrous (flowering of male inflorescence) occurs in the majority of cultivars and is brought in relation with the temperatures above 10°C which precede the flowering, while protogynous (flowering of female inflorescence) is less frequent and occurs at lower temperatures that precede the flowering (Piskornik et al, 2001). Hazel is an autosterile species (Thompson, 1979) which is characterised by the occurrence of incompatibilities between cultivars, so it is necessary to know mutually compatible cultivars and pollinators in order to avoid problems in the processes of pollination and fruit set (Olsen et al, 2000).…”