Inheritance of Leaf Characters in Sweet Potato (Ipomoea batatas [L.] Lam.)

Abstract

This study aimed to establish foundational knowledge regarding the inheritance patterns of two foliar traits (leaf morphology and midrib pigmentation) in Ipomoea batatas. To overcome the challenges associated with discretely classifying color and shape frequencies, five morphometric descriptors were employed. Two of these parameters addressed leaf shape (Circularity and Aspect Ratio), while three characterized the color of the central vein using the CIE L*a*b* color space. To elucidate the genetic control of these traits, parental genotypes exhibiting contrasting phenotypic attributes were selected, enabling the development of segregating populations. A total of 879 reciprocal crosses were performed, yielding 581 successful pollinations (63.87%). Incomplete dominance was observed for leaf morphology, with lobed leaves exhibiting dominance over the unlobed form. Regarding the circularity index, the highest frequency distribution (87.8%) fell within the 0.4 to 0.6 range. Segregation patterns for midrib color revealed a ratio of 4:1:4 among green, pink, and red phenotypes, respectively. Additionally, evidence of transgressive segregation was detected for both green and red pigmentation.