Morphological variation in selected Sri Lankan rice (Oryza sativa L.) accessions in relation to the vegetative parameters

Abstract

Morphological variation of 16 rice accessions representing both traditional and improved varieties was assessed using 12 vegetative traits as described in International Rice Research Institute descriptor for rice, in sand medium using a Complete Randomized Design. The single linkage clustering, morphological dendrogram, multivariate analysis of variance and the Principal Components Analysis were performed to assess the traits. According to the cluster analysis, accessions 2840 and 10617 were the most closely associated among the varieties. Based on the variations associated with morphologically important vegetative traits, all the rice accessions were classified into three major groups as two traditional and one new improved variety groups. Existence of such clusters was validated by the Wilks' lambda statistics. The first four principle components explained over 80% of the total variation associated with the varieties. Among them the first two principle component cumulatively explained 54.46% of the total variation. Rice accessions 8920 and 2835 representing Bg360 and Bg 450, respectively showed the highest principle component 1scores. Traditional rice varieties showed the comparatively higher scores in both principle components 1 and 2 than newly improved varieties. This study indicated that measured vegetative agro-morphological traits were helpful for preliminary characterization of varieties and also they can be used as a broad-spectrum approach to assess morphological diversity among morphologically distinguishable rice accessions.

Morphological variability of Indonesian rice germplasm and the associated SNP markers

“…This morphological traits related to leaf could be major descriptor contributing in differentiation of rice germplasm collection (Toshinori, 1991;Shikari et al, 2009). In addition, the contrast between the characters with a positive loaded value in PC1 but a negative loaded value in PC2 suggest that These predominant traits observed in our study like leaf, panicle and culm characters were also found to be important in other Asian countries (Shikari et al, 2009;Sinha and Mishra, 2013;Wijayawardhana et al, 2015).…”

“…Moreover, group or sub-gene pool within indica rice in tropical and temperate regions were still overlap, indicating seed exchange has been existed for many varieties/ accessions, in which diversified rice types were used for various agronomic and cultural practices. Importantly, the morphological changes probably were achieved by the successive rice improvement program (Wijayawardhana et al, 2015). Similar morphological characteristics that are expressed phenotypically could show dissimilarity among accessions in their genomes (Cole-Rodgers et al, 1997).…”

Assessment of morphological characteristics among upland rice (Oryza sativa and Oryza glaberrima) germplasm

“…According to Wijayawardhana et al (2015), cluster analysis has the singular efficacy and ability to identify crop accessions with highest level of similarity. The dendrogram obtained from the present study also proved the above statement in terms of similarity existing among accession further.…”

Morphological diversity of Sri Lankan traditional rice varieties “Pachchaperumal” and “Suduru samba”

“…An initial identification of the phenotypically distinguishable Sri Lankan traditional rice varieties could be important to assess the molecular genetic background and its diversity for future breeding approaches (Wijayawardhana et al 2015). Chandrarathna (1964) explained the gene interactions involved in pericarp colour as very important to determine the genetic variation of similar accessions of a variety.…”

“…According to the dendogram derived through the hierarchical cluster analysis based on morphological characters and flowering time, 2 major clusters were formed at the rescale distance of 25 separating accessions of (Suriyagoda et al 2011;Wijayawardhana et al 2015). An initial identification of the phenotypically distinguishable Sri Lankan traditional rice varieties could be important to assess the molecular genetic background and its diversity for future breeding approaches (Wijayawardhana et al 2015).…”