|Authors: ||L. Szalay, J. Papp, Z. Szaˇbo|
|Keywords: ||Prunus persica, flower buds, cold hardiness, dormancy, freezing tolerance|
During dormancy, flower buds are the most sensitive organs of the trees to frost.
Artificial freezing tests represent good tools both for determining the frost tolerance of different peach varieties and for measuring the dynamics of tolerance during winter.
Our aim was to determine the change in frost tolerance of six peach varieties (‘Babygold 6’, ‘Early Redhaven’, ‘Fairlane’, ‘Michelini’, ‘Redhaven’ and ‘Venus’) during dormancy.
For this, cold hardiness of flower buds was observed in two locations during two subsequent winters.
The buds were examined in artificial freezing tests and LT50 values were determined for each variety and sampling date.
Of the varieties, ‘Venus’ was the most sensitive to low temperatures, while the other varieties had similar level of frost tolerance.
The frost tolerance of flower buds were the highest in the middle of December, irrespective to variety.
The LT50 values were between -20 and -25 oC at this time.
There were no significant differences either between locations or in the change of frost tolerance of the peach varieties.
The dynamics of the varieties were similar to each other.
On the other hand, the effect of year was highly significant.
In 1998, due to the mild weather in January, the frost tolerance of flower buds decreased rapidly and the LT50 reached -15 oC by the middle of February.
In 1999, decrease in the level of frost tolerance of flower buds was significantly slower, due to the cold weather.
The LT50 values reached -15 oC only at the first half of March.
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