دانلود کتاب پیشرفت‌ها در زیست‌شناسی تکوینی در محصولات میوه درختی و آجیلی

Tree fruit and nut crops constitute a vital component of global agriculture, not only by virtue of their nutritional and economic importance, but also because of the complexity of their developmental processes. These crops often exhibit intricate regulatory networks that govern flowering, fruit set, fruit expansion, ripening, and senescence, all of which are significantly influenced by environmental conditions, genetic makeup, and horticultural practices [1]. Over the last two decades, extensive research has revealed that the developmental biology of tree fruit and nut crops is shaped by a multilayered interplay of hormonal signaling, transcriptional regulation, epigenetic modification, and metabolic reprogramming [2]. Advances in molecular tools and high-throughput “omics” approaches have accelerated our ability to decipher these complex networks, thus opening new frontiers in fruit quality improvement, stress tolerance, and sustainable orchard management [3]. Despite these remarkable strides, many gaps remain. One such gap concerns the interplay between hormone homeostasis and the transcription factors controlling fruit development. Classical phytohormones—such as auxins, gibberellins, cytokinins, abscisic acid, and ethylene—are well established as central regulators of fruit development and ripening [4]. However, new classes of regulators, including microRNAs and long noncoding RNAs, have been identified as having profound influences on gene expression and metabolic pathways during the progression of fruit growth and senescence [5]. The role of these non-coding RNAs in perennial fruit crops is less well characterized than in annual species such as tomato or Arabidopsis, indicating a pressing need for more comprehensive functional studies in tree fruit and nut crops [6]. In addition to hormonal and transcriptional regulation, fruit development is strongly impacted by carbohydrate metabolism, cell wall remodeling, and secondary metabolite biosynthesis. Carbohydrate availability in the developing fruit depends on source–sink relationships, which are dynamic throughout the growing season. Sink strength is modulated by the activity of sugar transporters, invertases, and other enzymes that allocate carbon to the developing fruit [7]. Meanwhile, the biosynthesis of pigments and secondary metabolites—such as anthocyanins, flavonols, and terpenoids—plays a key role in fruit quality, influencing color, flavor, and nutritional value [8]. These traits are crucial for consumer acceptance and market competitiveness. Modern breeding programs increasingly target these quality attributes, seeking to integrate molecular markers for sugar, acid, and secondary metabolite content into conventional breeding pipelines [9]. However, the genetic and biochemical networks underlying these traits can vary significantly across different tree fruit and nut species, complicating efforts in translating knowledge from model systems to diverse germplasm resources [10]. Climate change further complicates our understanding of developmental biology in perennial fruit and nut crops. Rising temperatures, altered rainfall patterns, and the increased frequency of extreme weather events challenge the stability of orchard systems worldwide [1]. Changes in winter chill accumulation, for instance, can disrupt dormancy release and flowering times, leading to mismatches between pollinators and bloom periods, ultimately affecting fruit set. Concurrently, abiotic stresses such as drought and salinity can drastically reduce photosynthetic efficiency, alter hormonal homeostasis, and accelerate or delay ripening [2]. Consequently, the need to develop climate-resilient cultivars and adaptive orchard management practices has never been more urgent. Researchers are thus intensifying their efforts to identify stress-responsive genes, investigate their regulatory mechanisms, and incorporate this knowledge into breeding programs and horticultural protocols [3]. In this rapidly evolving landscape, the application of cutting-edge technologies— ranging from CRISPR/Cas9-based gene editing to single-cell transcriptomics—has opened up unprecedented opportunities for dissecting and manipulating key developmental pathways [4]. Tree fruit and nut crops have historically lagged behind annuals in adopting such technologies, partly due to their extended juvenile phases, large genome sizes, and complex polyploidy in certain genera [5]. Yet, recent successes in the transformation and editing of fruit tree species suggest that the gap is closing. For instance, breakthroughs in Agrobacterium-mediated transformation protocols and the development of genotypeindependent transformation systems have significantly improved the feasibility of functional genomics studies in fruit crops [6]. Furthermore, the field is witnessing an expansion of integrated multi-omics approaches. By combining genomics, transcriptomics, proteomics, metabolomics, and epigenomics, researchers are painting an increasingly comprehensive picture of how multiple layers of regulation converge to shape fruit and nut development [7]. In particular, integrative omics has proven instrumental in pinpointing candidate genes and pathways linked to traits of agronomic interest, such as fruit size, flavor, texture, and stress tolerance [8]. Once identified, these candidate genes can be validated through functional assays, thus expediting the process of varietal improvement.