Identification and validation of informative SSR markers suitable for ensuring the genetic purity of brinjal (Solanum melongena L.) hybrid seeds

• 6 SSR markers identified for ensuring the identity and seed purity of brinjal hybrids.
• Multiplex PCR assay using 2 SSR markers establishes the identity of all 3 hybrids.
• Reliability of SSR marker assay in comparison with grow out test was established.

Farmers can harness the full potential of any hybrid only when they get genetically pure seeds of the hybrid. Hence, ensuring the genetic purity of certified seeds of brinjal hybrids is mandatory in India, which is done through field grow out test (GOT) based on the morphological characters of plants grown to maturity. GOT being land and labour intensive, time consuming and influenced by the environment, there is a need to identify rapid and reliable alternatives like DNA based assays. Therefore, the present study was undertaken to identify the SSR markers that could be used to test the genetic purity of three popular brinjal hybrids (viz., PH-5, PH-9 and Kashi Komal). Among 30 SSR markers studied, six markers were found to be suitable for testing the purity of these hybrids. The analysis of plant-to-plant variation within the parental lines of all the hybrids, using the identified hybrid specific markers, showed highly homogenous SSR profile, which further indicated the scope of application of these markers in maintenance and purity testing of hybrids and parental lines. Multiplexing of 2 polymorphic markers differentiated all the hybrids from each other, which can be used as referral markers for unambiguous identification, seed purity testing and protection of the hybrids. The validation of the identified markers in commercial seed lots of hybrids PH-5 and PH-9 revealed admixture of selfed seeds, which was confirmed through GOT.