Applications of CRISPR/Cas genome editing in economically important fruit crops:recent advances and future directions

Fruit crops,consist of climacteric and non-climacteric fruits,are the major sources of nutrients and fiber for human diet.Since 2013,CRISPR/Cas(Clustered Regularly Interspersed Short Palindromic Repeats and CRISPR-Associated Protein)genome editing system has been widely employed in different plants,leading to unprecedented progress in the genetic improvement of many agronomically important fruit crops.Here,we summarize latest advancements in CRISPR/Cas genome editing of fruit crops,including efforts to decipher the mechanisms behind plant development and plant immunity,We also highlight the potential challenges and improvements in the application of genome editing tools to fruit crops,including optimizing the expression of CRISPR/Cas cassette,improving the delivery efficiency of CRISPR/Cas reagents,increasing the specificity of genome editing,and optimizing the transformation and regeneration system.In addition,we propose the perspectives on the application of genome editing in crop breeding especially in fruit crops and highlight the potential challenges.It is worth noting that efforts to manipulate fruit crops with genome editing systems are urgently needed for fruit crops breeding and demonstration.

Recent progress and future prospects for mechanized harvesting of fruit crops with shaking systems

Mechanized harvesting technologies with shaking systems for fruit industry have been widely investigated and significantly developed over the past several decades which were presented by a large amount of literature.This paper reviews the research and development progress of mechanized harvesting of fruits systematically with a focus on the theoretical study,fruit crop variety,shaking system categories,abscission chemical agents,and their actual applications.Based on the comprehensive review,mechanized harvesting systems for different fruit crops appear multifarious shaking modes with various vibratory mechanisms and structural dimensions.Major advantages in the development of fruit mechanical harvesting with effective vibratory patterns and catching frames provide a series of economic and agronomic benefits,such as reducing labor costs,promoting standardized planting,and increasing productivity.However,fruit injury and tree damage are the main reasons why mechanical shaking systems are rarely used for fresh fruit harvesting because of tenderness and frangibility of the fruit crops.Therefore,more efforts should be concentrated on the innovative shake-and-catch system with suitable frequency and amplitude to achieve low fruit damage or even nondestructive harvesting for fresh fruit market.This overview summarized the advantages and bottlenecks of these shaking systems for fruit harvesting and proposed the challenges and some constructive prospective viewpoints aimed at the major issues of mechanical harvesting techniques.In addition,employing sorting technologies to classify the postharvest fruits provide a new direction for the further development of mechanized harvesting in high-value fruit crops,as well as bring more benefits to growers and increase their interest in equipment investment on the mechanical shaking harvester for the fruit industry.

Recent advances in fruit crop genomics

In recent years,dramatic progress has been made in the genomics of fruit crops.The publication of a dozen fruit crop genomes represents a milestone for both functional genomics and breeding programs in fruit crops.Rapid advances in high-throughput sequencing technology have revolutionized the manner and scale of genomics in fruit crops.Research on fruit crops is encompassing a wide range of biological questions which are unique and cannot be addressed in a model plant such as Arabidopsis.This review summarizes recent achievements of research on the genome,transcriptome,proteome,miRNAs and epigenome of fruit crops.