A fruit can be defined as a mature ovary. Fruit development can generally be considered to occur in four phases, viz., fruit set phase, rapid cell division, cell enlargement, and maturation and ripening. Generally, fruit development follows a sigmoid growth. But, in case of stone fruits and some other fruits double sigmoid growth curve is noticed. Fruit set normally requires the full completion of fertilization, although in some plants fertilization can be bypassed leading to the formation of a seedless fruit, a process referred to as parthenocarpy. Ruan et al., (2012) put forwarded sugar signalling model and multihormonal model, which regulate the fruit set process. After fruit set, cell division and cell enlargement phases are regulated by hormones and the hormonal environments are again governed by seeds. It was found that cell division phase is more critical than subsequent cell expansion in determining final fruit size. Fruit maturity is a developmental point where the fruit has reached the competence to ripen but has yet to start the ripening process. During maturation, changes in phenolic, anthocyanin and flavonoid compounds were noticed (Li et al., 2019). Ripening, a complex process involving changes to the metabolic and physiological traits of a fruit starts just after maturation. Ethylene is the major hormone, which regulates most of the events occur during ripening. Chlorophyll degradation is a significant event during fruit ripening, which is mediated by chlorophyllase enzyme. Accumulation of carotenoids at different development stages was co-ordinately controlled by differential expression of biosynthetic pathway genes especially DkPSY, DkZDS, DkLCYb and DkBCH (Qi et al., 2019). Chea et al., (2019) noticed activities of cell wall modifying enzymes, viz., Polygalacturonase, α-Arabinofuranosidase, β-galactosidase, α-Mannosidase, β-Xylosidase and Endo-1,4-β-xylanase, which modified the cell wall components of blueberry to make the fruit soft. Hydrolysis of starch to sugar is a characteristic feature of fruit ripening. During maturation and ripening, sugars accumulate, whereas organic acids that accumulated in young fruits strongly decrease. During ripening, the volatile aroma compounds including alcohols, aldehydes, and esters are also accumulated. Germacrene B is the aroma compound present in all the biotypes of pitanga fruit (Ramalho et al., 2019). During entire developmental process of a fruit, calcium plays a pivotal role. Lots of variations were noticed in the fruit development of various plant species. So, further studies are required in this line.

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