_____________________________________________________________________________________________________ *Corresponding author: E-mail: umaranierrabelli@gmail.com; Int. J. Environ. Clim. Change, vol. 12, no. 12, pp. 936-942, 2022 International Journal of Environment and Climate Change Volume 12, Issue 12, Page 936-942, 2022; Article no.IJECC.95319 ISSN: 2581-8627 (Past name: British Journal of Environment & Climate Change, Past ISSN: 2231–4784) Estimation of Genetic Parameters in Sunflower (Helianthus annuus L.) Germplasm Lines for Yield and Its Contributing Traits E. Umarani a* , A. Saritha a and A. V. Ramanjaneyulu b a Agricultural Research Station, Tornala, PJTSAU, Siddipet, Siddipet Dist., Telangana-502114, India. b AICRP on Agroforestry, PJTSAU, Rajendranagar, Hyderabad-500030, India. Authors’ contributions This work was carried out in collaboration among all authors. All authors read and approved the final manuscript. Article Information DOI: 10.9734/IJECC/2022/v12i121533 Open Peer Review History: This journal follows the Advanced Open Peer Review policy. Identity of the Reviewers, Editor(s) and additional Reviewers, peer review comments, different versions of the manuscript, comments of the editors, etc are available here: https://www.sdiarticle5.com/review-history/95319 Received: 15/10/2022 Accepted: 30/12/2022 Published: 30/12/2022 ABSTRACT Availability of appropriate genetic resources is a key to any crop improvement programme. The understanding and knowledge of genetic variation and genetic similarities present within individuals or populations are useful for the efficient use of genetic resources in breeding programme. Therefore, the present investigation was carried out to assess the variability, heritability and genetic advance in thirty-two sunflower germplasm lines for morphological characters. The analysis of variance revealed the presence of significant variability among the landraces of rice under study. Variability studies indicated that the estimates of phenotypic coefficient of variation (PCV) were slightly higher than genotypic coefficient of variation (GCV) for all the traits, indicating less influence of environment. Among all the characters under study, single plant yield exhibited highest PCV (38.64) and GCV (37.72), whereas lowest PCV (3.91) and GCV (3.49) were recorded for days to maturity. High heritability coupled with high genetic advance as per cent of mean estimates were Original Research Article