Evaluation or supercooling temperatures in apricot flowers

Document Type : Full Paper

Authors

1 PhD, University College of Agriculture and Natural Resources, University of Tehran, Iran

2 Associate Professor, University College of Agriculture and Natural Resources, University of Tehran, Iran

3 Professor, University College of Agriculture and Natural Resources, University of Tehran, Iran

4 Instructor of Agricultural Research Centre, Shahrood, Iran

Abstract

Late spring frost damage is the main factor that limits apricot production in Iran.
This research was aimed to evaluate the damage of freezing in two apricot cultivar
flowers: ʽʽNasiriʼʼ and ʽʽNori-Dirrasʼʼ during spring 2011. Reproductive organs of these
cultivars at two phenological stages, popcorn and full bloom, were transferred to
programmable freezer with temperature touch down from 5°C to -10°C. Temperature
were detected by the mean of thermocouple and recorded by a data logger connected to
a PC Computer. According to the results, differences between two cultivars and
interaction of cultivar and phenological stages were not significant, whereas the effect
of phenological stage was significant. The lowest supercooling temperature was -6.1°C
and recorded at full bloom stage in ʽʽNori-Dirrasʼʼ. More than 30% of ʽʽNori-Dirrasʼʼ
buds and more than 60% of its flowers showed less supercooling than -5°C. According
to this result, ʽʽNori-Dirrasʼʼ showed lower supercooling temperature than ʽʽNasiriʼʼ.

Keywords