Skin separation (puffiness) is a critical physiological disorder that significantly reduces the date palm (Phoenix dactylifera L.) fruit’s visual appearance and quality. The objectives of this study were to analyze fruit anatomy in skin-separated and normal date palm (var. Mejhoul) fruit and to assess the microclimatic conditions (temperature and relative humidity) during the fruit developmental stages and their association with skin separation. Fruit anatomy analysis was carried at different growth stages (Kimri-Khalal, Khalal, Rutab and Tamr) for two growing seasons. In addition, microclimatic conditions (specifically, temperature, and relative humidity) as well as soil moisture content were assessed across the study period 2020 and 2021. The anatomical analysis of the date palm fruit revealed that the exocarp or skin (cuticle, epidermis, hypodermis) thickness were quite similar across the developmental stages and over the study period (2020, 2021). Conversely, significantly more sclereid cells were found in skin-separated fruit (compared to normal fruit) at the Tamr stage. At that stage (Tamr), the percentage increase in sclereid cell number in skin-separated fruit ranged from 34–183%, sclereid clusters number 23–92%, cluster area 37–206%, and cluster perimeter 25–64%, as compared to normal fruit. In addition, sclereid cells at skin-separated areas of the fruit were clustered together, forming a chain of aggregates underneath the fruit skin, and were closer (42–50%, than normal) to the cuticle, leading to the partial separation of the exocarp from the fruit mesocarp. Although the weather data were similar across the growing seasons (temperatures, 33–34 °C; relative humidity, 45–46%), skin separation occurred in 14–15% of total fruit in 2020 and 30–34% in 2021. Therefore, we believe that skin separation disorder is not as heavily weather dependent as it seems to have been thought. In conclusion, changes in microclimate conditions were not the conclusive component for inducing the skin separation physiological disorder in date palm fruit. Further studies are required to identify the main factors that stimulate the development of sclereid clusters aggregates and the potential of agricultural practices to reduce skin separation.

Strawberries (Fragaria ananassa Duch.) are grown in Jordan year round due to the diversity of climatic conditions and the possibility of growing local or foreign varieties. More than six thousand g...

Next-generation sequencing technology was employed to read and assemble the complete plastid genome of the ‘Mejhoul’ date palm cultivar (Phoenix dactylifera L.). The genome consisted of 158,436 base pairs (bp) with a GC content of 37.24%, and it included 95 protein-coding genes, 44 tRNA genes, and eight rRNA genes. The plastome of five ‘Mejhoul’ genotypes from Jordan was compared with three genotypes from the USA, Morocco, and the UAE. It revealed 91 single-nucleotide polymorphisms (SNPs) and 23 insertions–deletions (InDels); the majority of them (62%) were located in intergenic regions, while the remaining variants were located in intragenic regions, including tRNA and rRNA genes. When the plastomes of all eight ‘Mejhoul’ genotypes were aligned, along with major cultivars ‘Barhee’ and ‘Khalas’, 24 SNPs and 23 InDels could be found. This would enable the development of a cultivar-specific fingerprint test for authentication. The phylogenetic tree was constructed using seventeen date palm cultivars. The phylogenetic analysis places ‘Mejhoul’ as a lineage derived within Clade I rather than as an early-diverging cultivar, suggesting it shares a more recent common ancestor with ‘Deglet Noor’ and ‘Barhee’.