Solanum insanum L. (Solanaceaeae) is the wild progenitor of common eggplant (S. melongena L.) and is naturally distributed in south and southeast Asia, Madagascar and Mauritius. Despite interest in its potential for eggplant breeding it has not been studied extensively. Solanum insanum has been subjected to various taxonomic treatments, with several discussions and arguments on its delimitation as a species, due to its close similarities with the cultivated S. melongena and the wild species S. incanum L. from the Middle East and northern Africa. Solanum insanum has long been used in a variety of medicinal and culinary preparations across many different Asian ethnolinguistic groups. Limited studies carried out on its chemical composition and pharmacognostical properties coupled with ethnobotanic studies reveal that S. insanum has potential for eggplant improvement with respect to phytochemical properties of interest for human health. Further study of morphological and genetic diversity in S. insanum is essential to promote its utilization in eggplant breeding, in light of its potential to hybridize with cultivated eggplant successfully. Here we compile and review the taxonomy, phytogeography, ecology and habitat characteristics, cytology, ethnobotany, breeding and phytochemical analysis of S. insanum. A comprehensive botanical description and illustrations for S. insanum are provided. A detailed comparison of S. insanum and its closely allied species, S. melongena and S. incanum is also made. The potential of S. insanum for crop improvement and future research priorities are discussed.

Elsevier Ranil, RH.; Niran, HML.; Plazas Ávila, MDLO.; Fonseka, R.; Hemal Fonseka, H.; Vilanova Navarro, S.; Andújar Pérez, I.... (2015). Improving seed germination of the eggplant rootstock Solanum torvum by testing multiple factors using an orthogonal array design. Scientia

Purpose: Solanum insanum L. is remaining as an underutilized crop due to little evidence from scientific studies on its medicinal and nutritional values.  Lack of such basic information on the plant obscured the in-depth biochemical or molecular studies as well as its uses in plant breeding. The study was aimed to identify the morphological variations of S. insanum and its selected biochemical properties.Research Method: Characterization of 71 accessions collected from different agro-ecological regions was carried out following the descriptor developed by the IBPGR and antioxidant activity, total phenolic content and browning of the fruits were also measured at the level of 5% probability.Findings: The results revealed that there were two distinct groups of S. insanum accessions, mainly based on prickliness of the plants. Non prickly plants showed 20.30 ± 0.52% radical scavenging activity (DPPH), 51.98 ± 0.16 mg/100 g fruit weigh (FW) of total phenolic content while prickly plants with 7.10 ± 0.59% radical scavenging activity (DPPH) and 50.62 ± 0.09 mg /100 g FW of total phenolic content in their fruits at the edible maturity. In terms of browning, time taken for color development up to “Grayed orange group 165 b” was 380 ± 10 seconds in fruits of non-prickly plants while 450 ± 17.32 seconds for fruits of prickly plants.Research limitations: Due to the out-crossing nature of the plant, it is difficult to find typical S. insanum plant either from wild or cultivated lands.Originality/Value: Characterization and evaluation of different accessions of S. insanum via morphological characteristics is a prime need before carrying out comprehensive biochemical or molecular studies. It provides fundamental basis for the classification based on vegetative, inflorescence and fruiting characteristics. Accordingly, the results will provide baseline information on S. insanum paving way to select superior germplasm for the taxonomists, breeders and those who are engaged in studies on S. insanum.