CHARACTERIZATION AND EVALUATION OF SUNFLOWER GERMPLASM FOR YIELD AND YIELD CONTRIBUTING CHARACTERS TO PERFORM WELL IN THE CONTEXT OF CLIMATE CHANGE IN BANGLADESH

Abstract

ABSTRACT A study on characterization and evaluation of yield and yield contributing characters of sunflower germplasm was carried out by using twenty-one sunflower (Helianthus annuus L.) genotypes in 2018-2019 at the research field of Oilseed Research Centre (ORC), Bangladesh Agricultural Research Institute (BARI), Gazipur, Dhaka. The aim of this study was to characterize the sunflower germplasm according to their yield contributing characters, estimate association among plot yield and yield related traits and partition the correlation coefficients into direct and indirect effects and identify high yielding, dwarf and short duration sunflower genotypes for future trial. Data were collected on days to 50% flowering, days to maturity, plant height (cm), head diameter (cm), stem diameter (cm), number of seed/head, 1000 seed weight (g), seed weight/head (g), % oil content and yield/plot (g). Mean performance of Sunflower accessions, variability of quantitative and qualitative morphological characters, correlation coefficient analysis, path coefficient analysis and cluster analysis were estimated. The ranges for days to 50% flowering, days to maturity, plant height (cm), stem diameter (cm), head diameter (cm), number of seeds/head, seed yield/head (g) ,1000 seed weight (g), % oil content and yield/plot (g) were 64-93, 92-137, 72.8-160.4 cm, 0.962.22 cm, 7.2-16.6 cm, 19-303, 1.2-18.8, 25-80 g ,37.20-40.33% and 49-525.2g respectively. The

genotype

ORCGP-21 produced taller plants of 160.4 cm and thicker stems of 2.22 cm. The genotype ORCGP-2 and ORCGP-13 produced maximum seed weight (80g). The genotype ORCGP-15 produced maximum oil percentage (40.325%) than rest of the genotypes. For the trait of yield/plot, the genotype ORCGP-21 produced maximum yield of 525.2g. Among the studied traits, high coefficients of variation were observed for the character seed yield/head (60.22g) followed by number of seeds/head (58.54) and plot yield (57.26 g). Plot yield was positively and highly significantly correlated with days to 50% flowering (0.55**), plant height (0.80**), stem diameter (0.56**), head diameter (0.40**), number of seeds per head (0.39**) and yield per head (0.34**).The path coefficient analysis showed that days to 50% flowering had the highest direct positive contribution on seed yield. Cluster analysis using R software classified the 21 sunflower populations into two main groups. A large number of accessions was placed in cluster V (6 accessions) followed by cluster I (5 accessions), cluster III (4 accessions) and cluster II and IV contains only three accessions. This result indicates a lot of diversity between these germplasm lines which can be exploited in future breeding program. The maximum genetic divergence was observed between cluster I and cluster V which may give rise to very good cross combination and desirable germplasms could be selected upon in the segregated generation. The accession ORCGP-16 and ORCGP-9 from cluster I and V respectively can be used in hybridization to synthesize new high yielding hybrids. The present study shows that short duration genotypes are ORCGP-14, ORCGP-15, ORCGP-16 and high-yielding varieties are ORCGP-6, ORCGP-10, ORCGP-11, ORCGP-12, ORCGP-16, ORCGP-21. It indicates that the inclusion of these genotypes as potential germplasms for future hybridization program would result in the development of superior sunflower cultivars.