ISSN 2756-3790
International Journal of Horticulture and Floriculture ISSN 2167-0455 Vol. 6 (4), pp. 001-005, April, 2018. © International Scholars Journals
Full Length Research Paper
Determining the chilling requirements of four Pistachio cultivars in Semnan province (Iran)
Hossein Afshari1, Ali Tajabadipour2, Hossein Hokmabadi2 and Mehdi Mohamadi moghadam2
11Horticulture Department, Islamic Azad University, Damghan Branch, Iran.
2Scientific board of Iran's Pistachio Research Institute, P. O. Box: 77175-435, Rafsanjan Iran
Accepted 15 January, 2018
Abstract
Most deciduous trees enter dormancy in respect to the shortening day length in fall; dormant buds re-quire a period of chilling to break this rest. The present research was carried out under laboratory con-ditions in order to determine the chilling requirements of 4 local cultivars of Damghan city. In this ex-periment some traits of flower bud breaking of mentioned cultivars in different chilling times (500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, and 1400 h) were studied. So an experiment as factorial in com-pletely randomized design established in two levels of cultivar and chilling. Results indicated that the chilling requirements of Akbari cultivar were higher than others. This was due to genetic differences among cultivars. Due to the direct effect of the chilling amount during blooming period from the very entering time of the buds to the greenhouse a measure known as the Chilling Requirement Index (CRI) was used. This index seemed to calculate the chilling effects more accurately. Chilling requirements were estimated to be 1100 h for Khanjari, Shahpasand, and Abasali cultivars and 1200 h for Akbari cultivar respectively. However, chilling more than the above amount was found to be effective on re-duction of the bud blooming time.
Key words: Abasali cultivar, Akbari cultivar, chilling requirement, Khanjari cultivar, Pistachio, Shahpasand cultivar.