Citrus indica Yu. Tanaka is a wild and endangered progenitor species of citrus endemic to North East (NE) India. It is reported to be restricted to Nokrek Biosphere Reserve in the Garo hills of Meghalaya. A wild orange morphologically resembling 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 was 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 citrus species found in Dailong Forest is monophyletic with the C. indica sequence reported earlier from Garo hills, Meghalaya. Both morphological and molecular characterizations confirm the taxonomic identity of the wild citrus collected from Dailong Forest of Manipur as C. indica. However, lack of knowledge and extensive deforestation in the particular habitat zone is posing a serious threat to the existence of this rare citrus species. There is an urgent need for the implementation of conservation strategies to safeguard this endangered species. This study also supports the evidence that NE India is one of the centres of citrus origin and the findings from this study could help in taking up proper conservation measures for the C. indica found in the region.

柑橘籼稻。田中是印度东北部 (NE) 特有的野生濒危柑橘祖先物种。据报道，它仅限于梅加拉亚邦加罗山的 Nokrek 生物圈保护区。在位于印度-缅甸生物多样性热点地区的曼尼普尔邦塔蒙隆区的戴隆森林中发现了一种形态类似于籼稻的野生橙子。进行了调查以确定可能的籼稻的确切身份，并研究了大龙林区的自然栖息地。使用三个叶绿体区域（trnL-F、psbK-I、matK-5'trnK间隔）和一个核（ITS）区域。系统发育分析表明，在戴龙森林中发现的柑橘属与早先在梅加拉亚邦加罗山报道的C. indica序列是单系的。形态学和分子学特征均证实了从曼尼普尔邦戴隆森林采集的野生柑橘的分类学特征为C. indica. 然而，在特定栖息地缺乏知识和广泛的森林砍伐正对这种稀有柑橘物种的存在构成严重威胁。迫切需要实施保护战略来保护这种濒临灭绝的物种。这项研究还支持印度东北部是柑橘产地中心之一的证据，这项研究的结果可能有助于对该地区发现的籼稻采取适当的保护措施。