this research was carried out to determine the chilling and heat requirements of grapevine cultivars(rotabi, siah shiraz and yaguti) and carbohydrate and hormones changes in chilled cuttings. uniform cuttings of above mentioned cultivars were harvested when leaves were abscised in autumn, and then transferred to refrigerator (2˚c). cuttingswere subjected to 0 (unchilled control), 100, 200, 300,...

it is necessary to determine the amount of chilling requirement of present cultivars and also to produce new low chill cultivars through breeding programs because of the global warming phenomenon and tendency to grow temperate fruit in warm climate. in this study, the amount of chilling requirement in ‘askari’, ‘rotaby’, ‘yaghuty’, ‘rish baba’ and ‘monaga΄ were evaluated. uniform cuttings of me...

Received for publication 21 Apr. 1999. Accepted for publication 5 May 1999. This work was supported by the U.S. Dept. of Agriculture–Agricultural Research Service, West Virginia Univ.–Agricultural Experiment Station, and the U.S. Dept. of Agriculture–National Research Initiative grant No. 9401825. West Virginia Univ. Agricultural Experiment Station Publication No. 2679. The cost of publishing t...

Most trees from temperate climates require the accumulation of winter chill and subsequent heat during their dormant phase to resume growth and initiate flowering in the following spring. Global warming could reduce chill and hence hamper the cultivation of high-chill species such as cherries. Yet determining chilling and heat requirements requires large-scale controlled-forcing experiments, an...

Global climate models predict an increase in the mean surface air temperature, with a disproportionate increase during winter. Since temperature is a major driver of phenological events in temperate woody perennials, warming is likely to induce changes in a range of these events. We investigated the impact of slightly elevated temperatures (+0.76 °C in the air, +1.35 °C in the soil) during the ...

Although, grapevines do not have a high chilling requirement, its fulfillment is critical for normal development of the vines. In tropical and subtropical regions such as Farrashband, in the south of Iran, there is no adequate winter chilling to release bud dormancy in grapevines. So it is necessary to consider the effect of chemical dormancy–breaking agents on bud dormancy. In the present rese...

Endodormancy and the related chilling requirement synchronize seasonal development of trees from boreal temperate regions under climatic conditions prevailing at their native growing sites. The phenomenon endodormancy has been known whole-plant level for 100 years, in last couple decades, insights into physiological molecular basis its release have also obtained. Intriguingly, recent studies sh...