variety ( Yencho et al., 2012 ). Intumescences on sweetpotato have not been extensively studied, and very few published research articles discuss the development of this disorder on the crop. One paper, “Intumeszenze fogliari di ‘Ipomoea batatas,’” was
Joshua K. Craver, Chad T. Miller, Kimberly A. Williams, and Nora M. Bello
D. Michael Jackson, Howard F. Harrison, Robert L. Jarret, and Phillip A. Wadl
is wide genetic and phenotypic diversity within the worldwide sweetpotato and Ipomoea germplasm collections for breeding efforts ( Gichuki et al., 2003 ; Jarret et al., 2019 ; Khoury et al., 2015 ; Su et al., 2017 ). Sweetpotato has high genetic
M. Mcharo, D. LaBonte, R.O.M. Mwanga, and A. Kriegner
Molecular markers linked to resistance to sweetpotato chlorotic stunt closterovirus [SPCSV (genus Crinivirus, family Closteroviridae)] and sweetpotato feathery mottle virus [SPFMV (genus Potyvirus, family Potyviridae)] were selected using quantitative trait loci (QTL) analysis, discriminant analysis and logistic regression. Eighty-seven F1 sweetpotato [Ipomoea batatas (L.) Lam.] genotypes from a cross of `Tanzania' and `Wagabolige' landraces were used to generate DNA marker profiles for this study. Forty-five of the clones were resistant to SPCSV while 37 were resistant to SPFMV. A combination of 232 amplified fragment length polymorphism (AFLP) markers and 37 random amplified polymorphic DNA (RAPD) markers obtained were analyzed to determine the most informative markers. All three statistical procedures revealed that AFLP marker e41m33.a contributed the greatest variation in SPCSV resistance and RAPD marker S13.1130 accounted for most of the variation in SPFMV resistance. The power of discriminant and logistic analyses is that you do not need a parent-progeny population. An evaluation of these two models indicated a classification and prediction accuracy rates of 96% with as few as four markers in a model. Both multivariate techniques identified one important discriminatory marker (e44m41.j) for SPCSV and two markers (e41m37.a and e44m36.d) for SPFMV that were not identified by QTL analysis.
Giovanni A. Caputo, Phillip A. Wadl, Lambert McCarty, Jeff Adelberg, Katherine M. Jennings, and Matthew Cutulle
Sweetpotato [ Ipomoea batatas (L.) Lam] is an economically important crop in the United States; in 2017, its worth was more than $733 million ( U.S. Department of Agriculture, 2018 ), and a total area more than 60,000 ha was planted throughout the
Nicholas A. George, Kenneth V. Pecota, and G. Craig Yencho
selected sweetpotato ( Ipomoea batatas (L) Lam.) varieties and breeding clones, p. 281–286. Scientist and farmer: Partners in research for the 21st century. Program Report, 1999–2000. Program Report 1999–2000. International Potato Center, Lima, Peru Martin
J.R. Bohac and S. Rajapakse
An Ipomoea accession from Indonesia, originally classified as I. trifida, was found to segregate in flower morphology. It was hypothesized to be either a very close relative of I. batatas (6x sweetpotato), or a hybrid between I. batatas (6x) and I. trifida (2x). Twelve seedlings of this accession were grown and precise measurements of sepal angle, corolla shape, and root morphology were taken. Samples were also compared on the DNA level using molecular markers. Based on morphological measurements, it was found that some individual seedlings of the unknown Ipomoea accession were not significantly different than I. batatas; others were not significantly different than I. trifida. The control I. batatas and I. trifida lines were significantly different from each other. DNA flow cytometry was used to determine that all seedlings were diploids with the same amount of DNA per cell. Overall plant morphology and molecular analysis confirmed that all of the seedlings were very closely related and the segregation in flower morphology was not due to a seed mixture. This data is consistent with the hypothesis that the accession is a hybrid between I. batatas and I. trifida.
Ming Liu, Aijun Zhang, Xiaoguang Chen, Rong Jin, Hongmin Li, and Zhonghou Tang
). Sweetpotato [ Ipomoea batatas (L.) Lam.] is an important human food, animal feed, and industrial raw material, which is grown in more than 100 countries and mainly produced in China ( FAO, 2011 ; Jin, 2012 ). Sweetpotato is a typical “K-favoring” crop ( Tang
Meng Wei, Aijun Zhang, Hongmin Li, Zhonghou Tang, and Xiaoguang Chen
and S deficiency during wheat grain filling J. Expt. Bot. 59 3675 3689 Islam, M.S. Yoshimoto, M. Yahara, S. Okuno, S. Ishiguro, K. Yamakawa, O. 2002 Identification and characterization of foliar polyphenolic composition in sweetpotato ( Ipomoea batatas
R.L. Jarret, N. Gawel, and A. Whittemore
Twenty-four accessions of Ipomoea, representing 13 species of section Batatas and the outgroup species I. gracilis and I. pes-caprae were analyzed for restriction fragment length polymorphisms. Polymorphisms were detected by probing Southern blots of restriction enzyme-digested genomic DNA with 20 low or moderate copy number sequences isolated from an I. batatas cv. Georgia Red genomic library. Data were analyzed cladistically and phenetically. Ipomoea trifida, I. tabascana, and collection K233 are, of the materials examined, the most closely related to sweetpotato (I. batatas). Ipomoea littoralis, the only Old World species in the section, is a sister species to I. tiliacea. Ipomoea littoralis, I. umbraticola, I. peruviana, I. cynanchifolia, and I. gracilis are shown to be diploid (2n = 2x = 30). In contrast, I. tabascana is tetraploid (2n = 4x = 60). The intrasectional relationships of section Batatas species and the role of tetraploid related species in the evolution of the cultivated I. batatas are discussed.
Dapeng Zhang and Wanda W. Collins
Randomly amplified polymorphic DNA (RAPD) analysis was performed on 18 accessions belonging to four different species of the genus Ipomoea, including sweetpotato and three related species. Twenty-two out of 30 primers tested revealed polymorphisms among these four species. Eight primers were selected on the basis of the number and repeatability of polymorphism produced. With these, a total of 98 different DNA bands were obtained and 85% of them were polymorphic. Based on the presence/absence of the bands, a genetic similarity among accessions and among species was calculated. Unweighted pair-group method with arithmetical averages (UPGMA) based on the similarity coefficients clearly discriminated these four species. Ipomoea trifida and sweetpotato share more genetic similarity. Ipomoea triloba and I. leucantha fall into another cluster. This study demonstrated that RAPD techniques can be a very useful tool for genotype/accession identification and studying the genetic relationship among genotypes/accessions of sweetpotato and among species of Ipomoea.