Kiwifruit cultivation in Italy has spread in warmer areas in the last decade since the low risk of bacterial cancer infection. The rapid introduction of a new specie and cultivars in this area caused, in some cases, problems related to ununiform bud breaking, late frost injury and inconstant productivity. For this reason, it is of great interest to study the thermic requirements of the new cultivars introduced and possible strategies facilitating bud break and blooming. Chilling requirement (CR) needed to overcome endo dormancy in deciduous trees is variety specific. It is crucial, particularly for warm areas, to now this feature in order to match properly the plant requirement with the chill accumulation of the area. Once chilling requirement has been satisfied heat accumulation allows trees to overcome eco dormancy which is crucial to avoid the risk of late frost damages. Several approaches have been proposed for estimating thermic requirement and accumulation and their accuracy changed according to their complexity and to the area where they were applied. In this research three methods to estimate chilling environmental accumulation were compared: Chilling hours (CH) and Dynamic Model (CP). Using the same methods, the chilling requirements were estimated on 5 kiwifruit varieties belonging to A. Chinensis and A. Deliciosa by means of the forcing protocol. After 2 years of observations, in South Italy, the most accurate model seemed to be CP. A. Chinensis cultivar reported lower CR than A. Deliciosa and opposite results were found for heat requirement. The breaking agents Brecaut® was tested on Jintao cultivar investigating two factors: application time, in terms of percentage of chilling requirement satisfied, and dosage. The application within a window of 70 and 85% of satisfied chilling requirement at standard dosage appeared appropriate. The higher dosage (150%) increased the bud fertility in the basal part of the shoot.
Comparative estimation of chilling and heat requirement in five kiwifruit varieties and exploitation of this knowledge for the effective application of a breaking dormancy agent (Brecaut®) in cv Jintao®
L. Gaeta;P. Losciale
2024-01-01
Abstract
Kiwifruit cultivation in Italy has spread in warmer areas in the last decade since the low risk of bacterial cancer infection. The rapid introduction of a new specie and cultivars in this area caused, in some cases, problems related to ununiform bud breaking, late frost injury and inconstant productivity. For this reason, it is of great interest to study the thermic requirements of the new cultivars introduced and possible strategies facilitating bud break and blooming. Chilling requirement (CR) needed to overcome endo dormancy in deciduous trees is variety specific. It is crucial, particularly for warm areas, to now this feature in order to match properly the plant requirement with the chill accumulation of the area. Once chilling requirement has been satisfied heat accumulation allows trees to overcome eco dormancy which is crucial to avoid the risk of late frost damages. Several approaches have been proposed for estimating thermic requirement and accumulation and their accuracy changed according to their complexity and to the area where they were applied. In this research three methods to estimate chilling environmental accumulation were compared: Chilling hours (CH) and Dynamic Model (CP). Using the same methods, the chilling requirements were estimated on 5 kiwifruit varieties belonging to A. Chinensis and A. Deliciosa by means of the forcing protocol. After 2 years of observations, in South Italy, the most accurate model seemed to be CP. A. Chinensis cultivar reported lower CR than A. Deliciosa and opposite results were found for heat requirement. The breaking agents Brecaut® was tested on Jintao cultivar investigating two factors: application time, in terms of percentage of chilling requirement satisfied, and dosage. The application within a window of 70 and 85% of satisfied chilling requirement at standard dosage appeared appropriate. The higher dosage (150%) increased the bud fertility in the basal part of the shoot.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
