Rediscovery and Characterization of Citrus Indica Tanaka, A Wild Endangered and Progenitor Species in Dailong Forest, Manipur, and Recommendations for Its Conservation.

Abstract Citrus indica Tanaka is a wild endangered and one of the progenitor species of citrus endemic to North East (NE) India, which is reported in Nokrek Biosphere Reserve in the Garo hills of Meghalaya. A wild orange morphologically claimed to be C. indica was encountered in the Dailong forest of Tamenglong district, Manipur which is located in the Indo-Burma biodiversity hotspot region. Surveys were conducted to establish the exact identity of possible C. indica and study the natural habitat in Dailong forest area. The traditional morpho-taxonomic description for the identification of the plant is performed along with the molecular characterization using three chloroplast regions (trnL-F, psbK-I, matK-5′trnK spacer) and one nuclear (ITS) region. Phylogenetic analysis revealed that the C. indica found in Dailong Forest is monophyletic with the earlier reported C. indica sequence from Garo hills, Meghalaya. Both morphological and molecular data support the identity of C. indica that has been collected from Manipur. However, lack of knowledge and clearing of forest cover has led to an urgent need for the implementation of conservation strategies to safeguard this endangered species. This study supports the evidence that NE India is one of the origin centres for citrus and this finding can guide the conservationists to initiate priority for adopting possible methods of proper conservation of C. indica in the region.