SHORT COMMUNICATION Expression study of five genes involved in floral organ development in multiple seeded rice Soumya Prakash Das 1 • Debal Deb 2 • Narottam Dey 1 Received: 22 September 2018 / Accepted: 9 August 2019 Ó Society for Plant Biochemistry and Biotechnology 2019 Abstract Rice cultivar Jugal is a unique floral organ mutant from South Bengal and Odisa, the two sister states of Eastern India, carries more than one kernels in most of its spikelet. Most of the mature florets of this line possess more than one carpal which later developed into more than one kernels within a single grain on maturity. In order to study the role of floral organ development genes commonly involved, expression study of five selected floral organ developmental genes (OsMADS3, OsMADS13, OsMADS21, OsMADS58, and DL) were studied through real time based quantitative PCR for three con- secutive flower organ developmental stages (Sp5, Sp6, and Sp7) with reference to a normal rice line (IR36). All the studied genes showed differential relative expression in respect to the reference gene both in mutant and normal rice lines for the studied genes and stages and individual distinct pattern except DL gene which was almost similar in both Jugal and IR36 at early stage of floral organ development viz Sp5 and Sp6 stage. However, after Sp6 stage the expression is reduced in the normal rice (IR36) but in case of the mutant rice (Jugal) the expression started to increase and at Sp7 the expression level was much higher in the mutant line. The information resulted from the investigation form the basic idea on regulatory aspects of floral organ development in rice. Keywords Multiple seeded rice Á Floral organ mutant Á OsMADS Á DL Á Relative gene expression Abbreviations AG Agamous CRC Crabs claw DL Drooping leaf OsMADS Oryza sativa MADS-box Floral organ development is one of the most important physiological phenomenon in plants which determine the successful development of fruits through a series of phys- iological process. The most popular and elaborate genetic model describing the floral organ development in higher group of plants is the ABCDE model (Soltis et al. 2007; Dreni and Kater 2014; Hu et al. 2015) which was originally postulated for the model plant Arabidopsis thaliana and later extended for rice, the model plants of monocot where floral meristems first produces a lemma and a palea in opposite positions on the flank followed by two lodicules which are thought to be homologous to the petal of dicots. Six stamens then emerge in the whorl between these accessory parts and meristematic regions followed by a carpel at the centre of the flower. In addition to the normal regular floral structure, a number of natural mutant forms are available where either the number or the position of individual floral organ parts is altered. The mutant lines where floral organ numbers are altered are known as floral organ mutant. Detailed genomic study showed that AGA- MOUS (AG) gene of Arabidopsis which is the class-C function gene encodes MADS-box transcription factors which are reported to play crucial roles in floral meristem determinacy (Kyozuka et al. 2000; Kellogg 2001; Bommert et al. 2005; Zanis 2007). In rice AG subfamily genes were included into two groups (class C and class D gene family). The OsMADS3 and OsMADS58 are rice C-lineage genes & Narottam Dey narottam.dey@visva-bharati.ac.in Soumya Prakash Das soumyaprakash.das@visva-bharati.ac.in Debal Deb debaldeb01@yahoo.com 1 Rice Biotechnology Laboratory, Department of Biotechnology, Visva-Bharati, Santiniketan, West Bengal 731235, India 2 Centre for Interdisciplinary Studies, Basudha Biotechnology Laboratory for Conservation (Basudha Trust), 9 Old Calcutta Road, Barrackpore, Kolkata, West Bengal 700123, India 123 Journal of Plant Biochemistry and Biotechnology https://doi.org/10.1007/s13562-019-00526-y