Citrus, belonging to the Rutaceae family, is a commercial fruit worldwide, and it is mainly recognized for its nutritional, anti-oxidant, and significant medicinal properties. Citruses are a group of multifaceted fruit crops with a rich traditional knowledge, deeply rooted in ethnic culture, and the fruits have been considered to be health-protecting and health-promoting food supplements since ancient times. The presence of secondary metabolites and their bioactivities has led to the development of new alternative drugs in recent years. Diverse secondary metabolites such as flavonoids, alkaloids, carotenoids, phenolic acids, and essential oils and their high bioactive properties have imparted great value to human health based on their anti-oxidative, anti-inflammatory, anti-cancer, cardiovascular protective, and neuroprotective effects. The indigenous Citrus species of India—mainly Northeast India—have distinctive and valuable genetic traits, such as resistance to biotic and abiotic stress, distinctive aroma, flavor, etc. Hence, these species are considered to be repertoires of valuable genes for molecular breeding aimed at quality improvement. There is a need for awareness and understanding among the citrus-producing countries of the exploitation of biodiversity and the conservation of Citrus for sustainable development and bioprospecting. The current review presents a holistic view of Citrus biodiversity from a global perspective, including phytochemical constituents and health benefits. Advanced biotechnological and genomic approaches for Citrus trait improvement have also been discussed to highlight their relevance in Citrus improvement.

Citrus plants have a secure and important place in human health. Citrus is not only significant for its delicious fruits but also because of certain medicinal and pharmacological properties. The presence of secondary metabolites like flavonoids, limonoids, alkaloids, phenolics and coumarins has dramatically increased its efficacy in treating bacterial and fungal infections. Emergence of new and improved extraction techniques has helped researchers to isolate novel phytochemicals from citrus species, and there is a greater attention. Numerous studies throughout the world have focused to isolate novel metabolites from citrus plants. There is a rich biodiversity of citrus species in the Indian subcontinent based on climatic condition which supported the growth and maintenance of diverse varieties. Analysis of metabolomic and medicinal properties of local citrus plant will aid in understanding their importance in pharmacological industry. The present review is focused on the medicinal and secondary metabolite profile of citrus plants from India.

The importance of the citrus crops is recognized throughout the world. Despite tremendous advancements in agricultural technology, citrus fruit production is still considered a significant challenge. Various biotic factors have trampled down the production rate of Citrus in many places. Among them, canker caused by Xanthomonas axonopodis pv. citri (Xac) and Xanthomonas citri pv. citri (Xcc) is of great importance. Infection caused by Xac leads to lesion development in leaves, fruits, and stem. Defoliation and early fruit drop can occur as a result of severe infection, resulting in a loss of fruit output. Preliminary management techniques involve quarantining and sanitizing. Chemical copper-based bactericides are frequently employed in places with large-scale production. However, the continued use of chemicals, on the other hand, has led to the evolution of resistant microorganisms and increased the rate of soil pollution. Various alternative strategies have been suggested to address this issue. This review will go over the advances in biocontrol agents that have been used to combat the disease.