干旱区生态环境知识资源中心

Thirty vegetative date palm (Phoenix dactylifera L.) descriptors were screened. This selection was made on three cultivars with variable behaviour towards oasis stress: Deglet nour, Alig and Kintichi. The statistic tests showed an intra-cultivar stability of 6 characters: percentage of spinned midrib part, apical divergence angle, maximal pinnae width at the top leaf, percentage of solitary spine, spine length at the middle and maximal spine angle. These characters are steady; their measures are not affected by the change of cropping conditions. So they can be used for cultivars identification in any oasis and outside the fruiting period. Using these parameters, the genetic variation among 26 Tunisian date palm cultivars was studied. The graphic distribution identified by principal component analysis showed cluster according to fruit characteristics. We have distinguished a grouping of later maturity date palm varieties which opposed to those with earlier maturity. The Pearson coefficient showed significant correlation between the harvesting period and the percentage of spinned midrib part which can be used as an indicator of the cultivar maturity period. In addition, cultivars with the same fruit consistency are grouped together. These results are useful in the selection, collections and genes mapping.