Vol. 11, Issue 2 (2022)

Author(s):
SK Mundotiya, Jagdish Goyanka, Ravi Kumar Mundotiya and Sunil Ramling Swami

Abstract:
Rice (Oryza sativa L.) is one of the cultivated cereal plant species, known to show the wide diversity and adaptability to growing conditions. The Plant Variety Protection system varied considerably among different countries and was adopted as per the needs and international conventions. Under the PPV&FR Act, rice varieties are registered on the basis of Novelty, Distinctiveness, Uniformity and Stability (NDUS) characters which are taken as per the stage of observations listed in DUS guidelines. Keeping in view the importance of DUS test for cultivar characterization and differentiation, the present study was carried out to characterize the extant rice varieties for plant morphological traits and assessment the extent of variability and associated constraints in these varieties for above characters. The complete DUS database of plant morphological characters for all the rice varieties were generated as per DUS guidelines (Rice) no. SG/ 01/ 2007. The study grouped the 28 rice extant varieties into five different clusters based on these DUS parameters. The experimental material under study thus revealed considerable variability for most of the morphological characters, indicating their utility in the characterization and use in rice variety improvement programme. At the same time DUS characterization has limitation as morphological differences between the varieties is less due to narrow genetic base and requires skilled human power which is subjective in nature. Also this process is time, labour and cost intensive. Hence, the manual identification of varieties/seeds by specialized technicians is slow, has low reproducibility, and possesses a degree of subjectivity that is hard to quantify. So, it is suggested that in addition to the existing DUS guideline for establishing varietal distinctiveness, recent technologies like use of molecular markers or image analysis techniques need to be complemented with field morphological studies to have a more reliable assessment.