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Citrus is one of the most important and widely grown fruit crops around the world. Citrus fruit drop is due to the influence of various biotic and abiotic factors. Major biotic factors include insects like fruit flies and diseases such as Huanglongbing (HLB) and postbloom fruit drop (PFD) due to Colletotrichum acutatum. The associated abiotic factors are temperature, rainfall, hailstorms, water stress, nutritional imbalance, etc. Studies have been conducted to understand fruit drop and its relation to various plant growth regulators. Plant growth regulators such as auxin and gibberellins have been categorised as abscission inhibitors, while ethylene, abscisic acid (ABA) and methyl jasmonate (MJ) are abscission promoters. Here, in this review, we have emphasised on the different phases of fruit drops, factors causing fruit drop, the role of plant growth regulators, fruit detachment force (FDF), rootstocks, water relation, nutrient status and different chemical, biological, botanical and hormonal strategies applied for controlling citrus fruit drop. Moreover, we have also discussed the molecular basis of citrus fruit drop and have reviewed recent studies involving biosynthesis/signalling pathway genes and phytohormone genes affecting fruit drop. This review offers comprehensive information about citrus fruit drop and shall provide the direction of future research for students, horticulturists, researchers and other stakeholders.

C3HC4-type RING finger gene family is one of the largest, ubiquitous, and diverse proteins, involved in positive regulation of stress response, and enhances drought and salt stress tolerance. The genome-wide characterisation and biological functions of this family protein are well characterised in several plants and animals. However, their characterisation and functions in Capsicum and its related species are unknown. In this study, we identified 16 C3HC4-type RING finger family genes in pepper (Capsicum annuum L). Moreover, chromosome localisation, gene structure, phylogenetic relationships, conserved domain analysis, and cis-element analysis were carried out. In silico expression analysis was carried out to determine the level of expression of these genes in different tissues of pepper. Moreover, RT-qPCR analysis validated that CaRHC1, CaRHC7, and CaRHC13 are upregulated, while CaRHC3, CaRHC4, and CaRHC6 are downregulated in various tissues of pepper. Upregulation and downregulation of few candidate C3HC4-type RING finger genes in the placenta and pericarp of pepper indicates their possible role in capsaicin biosynthesis and pungency, which needs to be investigated further. Thus, the genome-wide analysis provides a comprehensive understanding of C3HC4-type RING finger gene family in Capsicum genome and it shall help to design effective strategies for functional analysis of these genes.