Together with lime, lemon is recognized as the third most extensively cultivated citrus species worldwide, trailing only behind orange and mandarin. The enhancement in the economic value of lemons as a valuable resource in Southern Italy depends by the competitiveness of local lemon production in both domestic and international markets. This necessitates conducting a comprehensive study that thoroughly explores the available indigenous germplasm at the local and national levels. This study aims to identify the most promising Sicilian and Campanian cultivars that are well suited for both fresh fruit consumption and the production of processed goods. This re-study assumes even greater importance considering the ongoing climate changes, as environmental stresses significantly impact the ripening process and the timing of fruit development. Our study has highlighted a notable diversity among the 18 investigated lemon cultivars, particularly highlighting specific cultivars that possess desirable attributes for fresh consumption. The cultivars that showed the greatest cumulative production over the 10 years of the study were Erice with 467.89 kg/tree and Femminello Siracusano 2KR with 408.44 kg. Notably, cultivars like Segesta, Erice, and Kamarina have exhibited higher percentages of juice content ranging from 27.30% to 31.08%. These cultivars show great potential for abundant juice content and optimal acidity levels for direct consumption. On the other hand, cultivars characterized by enhanced yield, such as Femminello Siracusano 2KR, Femminello Fior d’Arancio m79, and Erice, may prove to be particularly well suited to produce processed goods. Overall, our findings provide valuable insights into some qualitative parameters of lemon cultivars, important either for fresh consumption or for transformed products.
Almond (Prunus dulcis (Mill.) D.A. Webb) is one of the most economically important nut crops worldwide, valued for its nutritional properties and adaptability to diverse agroecological environments. This review summarizes current knowledge on almond domestication, genetic diversity, production trends, and improvement strategies, with a focus on drought tolerance under climate change. Archaeobotanical and molecular evidence indicate central Asia and the eastern Mediterranean as key centers of origin, where recurrent introgression from wild Prunus species contributed to the high genetic variability of cultivated almond. Global production trends reveal increasing challenges due to prolonged drought, climate variability, and rising water and energy costs, particularly affecting major producers such as the United States. Mediterranean regions are transitioning from traditional low-density orchards to intensive systems, where cultivar and rootstock choice are crucial for sustainability. Self-fertile and late-blooming cultivars improve yield stability, while interspecific hybrid rootstocks enhance water use efficiency and tolerance to drought and poor soils. Drought stress impacts almond physiology and yield, although moderate deficit irrigation can maintain productivity and improve kernel quality. Future improvement relies on germplasm conservation, marker-assisted selection, and genomic tools to develop climate-resilient cultivars integrated with sustainable water management strategies.
Despite the economic and ecological importance of the carob tree, few studies are available on the morphological characterization and chemical composition of carob in Algeria. This has resulted in the lack of selection of commercial cultivars of high seed and sugar content. The present study aims to assess the diversity of 11 wild and 1 cultivated carob populations in various regions of Algeria, characterized by diverse geographical and climatic conditions. The final objective is to assess the diversity of neglected carob plants that exhibit superior fruit quality traits and/or are well adapted to different pedoclimatic conditions. The current study focuses on analyzing pod and seed diversity by investigating 12 morphological and 5 physiochemical traits. The analysis of variance revealed significant differences between populations (p < 0.001) for all traits studied, indicating high morphological and chemical variability among these carob populations. Principal component analysis (PCA) was employed to study the relationship between these traits and the geographical origin. High seed yields characterized wild populations, whereas cultivated populations were rich in sugar. Based on morphological traits of pods, seeds and chemical compositions, a hierarchical clustering grouped the carob populations into four groups. The findings of this study represent a significant advancement towards establishing effective cultivar breeding programs in Algeria. They demonstrate that the germplasm examined in this research exhibits an optimal level of morphological and chemical diversity, which is instrumental in the identification of specific traits of both commercial and environmental significance.
Carob (Ceratonia siliqua L. Fabaceae) is a species of significant economic, ecological, and cultural importance in the Mediterranean region. It is valued for its adaptability to various environments and wide-ranging agricultural and industrial applications. Despite its potential, the genetic characterization of this species in Algerian territories has received little attention to date. The present study aims to decipher carob’s genetic structure and diversity in Algeria. This study presents a comprehensive morphological characterization of 39 Algerian carob accessions based on pod traits and molecular genotyping using eight nuclear and three chloroplast SSR markers across different geographical locations and environmental conditions. The morphological analysis revealed a discrete differentiation among accessions, primarily influenced by their area of origin. The genetic analysis identified 38 unique genotypes. Allelic richness indicated high polymorphism, with an average of 3.81 alleles and 5.36 genotypes for nuclear SSR markers. Chloroplast SSR markers showed lower variability but provided insights into population structure. Genetic analysis revealed distinct genetic clusters aligned with geographical and bioclimatic regions, supported by minimum spanning network analysis that showed the genetic flow patterns among accessions. Discriminant analysis of principal components identified five optimal sub-population groups, highlighting a genetic structure linked with different bioclimatic conditions. These findings evidence the complex genetic diversity of Algerian carob germplasm and offer valuable insights for the sustainable exploitation of carob genetic resources.
Efficiency in vitro regeneration is a crucial prerequisite for the application of New Nenomics Techniques (NGTs) in grapevine (Vitis vinifera L.) for improving resistance to biotic and abiotic stresses. This is especially true given that their management must be addressed sustainably, considering the impact of climate change. Unfortunately, in vitro plant regeneration and the establishment of embryogenic calluses are two genotype-dependent processes. Up to now, extensive research has been conducted on major international cultivars, whereas studies on the application of in vitro protocols for autochthonous cultivars remain limited. In this study, protocols for the acquisition of embryogenic calluses were applied on the most relevant Sicilian grapevine cultivars: the red-skinned ‘Frappato’, ‘Nerello mascalese’, and ‘Nero d’Avola’, and the white-skinned ‘Grillo’, ‘Carricante’, and ‘Catarratto’. Stamens and pistils were cultured in two different induction media (PIV and MSII) and at three stages (mother cells in the late premeiotic phase, tetrads, and mature pollen) to induce embryogenic calluses. Five thousand explants per cultivar were cultured, forming calluses in four selected cultivars. Plantlets were successfully generated from calluses of ‘Carricante’, ‘Frappato’, and ‘Nero d’Avola’. Moreover, protoplasts were isolated from ‘Frappato’ and ‘Nero d’Avola’. Our results establish a critical foundation for developing successful regeneration protocols for the future application of NGTs in Sicilian grapevine cultivars.
In plants, xylem is directly involved in conveyance of water and dissolved minerals, mechanical support of the plant, and tolerance to drought stress. Moreover, for several fruit crops affected by vascular diseases, an association between the morphology of xylem vessels and susceptibility was described. In fact, compartmentalization represents a key determinant mechanism of plant resistance to vascular infections. Mal secco is a severe tracheomycosis affecting many citrus species of relevant economic importance. Currently, both chemical and agronomic measures are not sufficient to contain the diffusion of the pathogen raising the interest for the elucidation of the host tolerance mechanism against mal secco. This study investigated the constitutive morphology of xylem tissue, in terms of vessel diameter and vessel density in 28 citrus genotypes, all characterized by a different degree of tolerance/susceptibility towards the disease. One‐year‐old stems, in three replicates per each genotype, were cut into 50‐μm sections and observed under an optical microscope after staining in safranine‐O. Analysis revealed a positive correlation between xylem vessel density and susceptibility to mal secco disease. These findings suggest that the constitutive morphology of xylem tissue could play a role in tolerance to mal secco, even though other mechanisms, both at histological and biochemical level, need to be unlocked and better elucidated.