and Mackill 2009). Furthermore, CDDP marker techniques are agarose gel‐based, convenient, highly polymorphic, and capable of generating markers that are phenotypically linked to traits (Collard and Mackill 2009). The CDDP markers are similar in principle to resistance gene analog markers, designed from conserved regions in plant disease resistance genes (Chen et al. 1998). They possess different putative domains including auxin‐binding proteins, transcriptional factors for development, physiology, fruiting, and ripening processes, plant disease resistance pathways, secondary metabolism, abiotic and biotic stresses, and cellular morphogenesis (D'Hont et al. 2012). It has been shown that, within functional domains of well‐characterized plant genes, the CDDPs can generate informative banding patterns that are utilized for mapping, trait association, and germplasm genetic diversity studies (Collard and Mackill 2009; Poczai et al. 2013). Due to the inherent efficiency and ability of CDDP to easily generate functional markers (FMs) that are associated with given plant phenotypic expressions, they have been used in the improvement of different crops including Rosa rugosa (Jiang and Zang 2018); Chrysanthemum cultivars (Li et al. 2013); Peony cultivar (Li et al. 2014); bittersweet (Solanum dulcamara) (Poczai et al. 2011); date palm (Mam et al. 2017); Chickpea (Cicer arietinum L.) (Hajibarat et al. 2015); rice (Oryza sativa) (Collard and Mackill 2009); and wheat (Triticum aestivum L.) (Hamidi et al. 2014; Seyedimoradi et al. 2016).
Inter‐simple sequence repeat (ISSR) markers are arbitrary and target multiple genomic loci for amplification of DNA segments present between two identical microsatellite regions that are opposite with each other in orientation (Zietkiewicz et al. 1994), while SCoT markers were developed to target the conserved regions of the genome across various plant species due to their longer primer lengths and high annealing temperatures (Collard and Mackill 2009). However, ISSR and SCoT markers have been found useful in various crops for genetic diversity studies because of their high reproducibility and efficiency for detecting polymorphisms (Guo et al. 2012; Hamidi et al. 2014; Lamare and Rao 2015; Etminan et al. 2016; Igwe et al. 2017). Here, we utilize a basic systematic approach (Figure B7.4) involving the informative molecular markers (CDDP, SCoT, and ISSR) that generate unique and reproducible alleles (Figures B7.5–B7.7) to assess vital genetic diversity indicators and population structure of Musa species accessions for identification of those with novel traits and unique allelic variants. The identified ones are selected for mass production, maintenance, and germplasm conservation to ensure continuous availability to the farmers and breeders.
Figure B7.4 Summary of research activities on Musa species at the Center for Natural Sciences, Nursing, and Mathematics, Department of Natural Sciences, Bowie State University.
Figure B7.5 Amplification profiles of 66 banana and plantain samples using WRKYMus1a primer of CDDP marker gene: a = 1 kb step DNA ladder and b = 100 bp DNA ladder. Sample order (1–66 from left to right): 1 = Fougamou 1, 2 = Obino I'Ewai, 3 = Calcutta 4, 4 = Improved Lady Finger, 5 = Blue Torres Strait Island, 6 = Silk, 7 = Truncata, 8 = Cardaba, 9 = Lidi, 10 = Pelipita, 11 = Pelipita Manjoncho, 12 = Lai, 13 = Higa, 14 = Pisang Keling, 15 = Pisang Lawadin, 16 = Balonkawe, 17 = Gros Michel, 18 = Green Red, 19 = Plantain no.3, 20 = Pata, 21 = Chinese Cavendish, 22 = Dwarf Parfitt, 23 = Hochuchu, 24 = Umalag, 25 = Hsein Jen Chiao, 26 = Mons Mari (Pedwell), 27 = Lady Finger (Nelson), 28 = Pisang Rajah (South Johnstone), 29 = Tani, 30 = Pisang Lilin, 31 = Poteau Geant, 32 = Pisang Klutuk Wulung, 33 = Garbon 2, 34 = Zebrina (G.F), 35 = Khae (Phrae), 36 = Dole, 37 = Wompa, 38 = Pisang Palembang, 39 = Pisang Awak, 40 = Williams (Bell, South Johnstone), 41 = Plantain No.17, 42 = Kluai Tiparot, 43 = Tiau Lagada, 44 = Niyarma Yik, 45 = Selangor, 46 = Long Tavoy, 47 = Malaccenesis, 48 = Figure Pomme Geante, 49 = Highgate, 50 = Borneo, 51 = Honduras, 52 = Pome, 53 = Kunnan, 54 = Musa beccarii, 55 = Musa coccinea, 56 = JD Yangambi, 57 = Musa textilis, 58 = Tomolo, 59 = Pisang Berlin, 60 = FHIA‐23, 61 = No. 110, 62 = Dwarf Cavendish, 63 = SH‐3436‐6, 64 = Lal Velchi, 65 = Madang, and 66 = FHIA‐21 (#68). The primer, WRKYMus1a of CDDP marker, demonstrates polymorphism as indicated by the red colored arrows in the gel image.
Figure B7.6 Amplification profile of 66 banana and plantain samples using Start codon targeted 26 (SCoT26) polymorphic marker: a = 1 kb step DNA ladder and b = 100 bp DNA ladder. Sample order (1–66 from left to right): 1 = Fougamou 1, 2 = Obino I'Ewai, 3 = Calcutta 4, 4 = Improved Lady Finger, 5 = Blue Torres Strait Island, 6 = Silk, 7 = Truncata, 8 = Cardaba, 9 = Lidi, 10 = Pelipita, 11 = Pelipita Manjoncho, 12 = Lai, 13 = Higa, 14 = Pisang Keling, 15 = Pisang Lawadin, 16 = Balonkawe, 17 = Gros Michel, 18 = Green Red, 19 = Plantain no.3, 20 = Pata, 21 = Chinese Cavendish, 22 = Dwarf Parfitt, 23 = Hochuchu, 24 = Umalag, 25 = Hsein Jen Chiao, 26 = Mons Mari (Pedwell), 27 = Lady Finger (Nelson), 28 = Pisang Rajah (South Johnstone), 29 = Tani, 30 = Pisang Lilin, 31 = Poteau Geant, 32 = Pisang Klutuk Wulung, 33 = Garbon 2, 34 = Zebrina (G.F), 35 = Khae (Phrae), 36 = Dole, 37 = Wompa, 38 = Pisang Palembang, 39 = Pisang Awak, 40 = Williams (Bell, South Johnstone), 41 = Plantain No.17, 42 = Kluai Tiparot, 43 = Tiau Lagada, 44 = Niyarma Yik, 45 = Selangor, 46 = Long Tavoy, 47 = Malaccenesis, 48 = Figure Pomme Geante, 49 = Highgate, 50 = Borneo, 51 = Honduras, 52 = Pome, 53 = Kunnan, 54 = Musa beccarii, 55 = Musa coccinea, 56 = JD Yangambi, 57 = Musa textilis, 58 = Tomolo, 59 = Pisang Berlin, 60 = FHIA‐23, 61 = No.110, 62 = Dwarf Cavendish, 63 = SH‐3436‐6, 64 = Lal Velchi, 65 = Madang, and 66 = FHIA‐21 (#68). Some unique banding patterns are shown by the red arrows in some of the accessions.
Figure B7.7 Amplification profile of 66 banana and plantain samples using Inter‐simple sequence repeat 901 (UBC901) polymorphic marker: a = 1 kb step DNA ladder and b = 100 bp DNA ladder, Sample order (1–66 from left to right): 1 = Fougamou 1, 2 = Obino I'Ewai, 3 = Calcutta 4, 4 = Improved Lady Finger, 5 = Blue Torres Strait Island, 6 = Silk, 7 = Truncata, 8 = Cardaba, 9 = Lidi, 10 = Pelipita, 11 = Pelipita Manjoncho, 12 = Lai, 13 = Higa, 14 = Pisang Keling, 15 = Pisang Lawadin, 16 = Balonkawe, 17 = Gros Michel, 18 = Green Red, 19 = Plantain no.3, 20 = Pata, 21 = Chinese Cavendish, 22 = Dwarf Parfitt, 23 = Hochuchu, 24 = Umalag, 25 = Hsein Jen Chiao, 26 = Mons Mari (Pedwell), 27 = Lady Finger (Nelson), 28 = Pisang Rajah (South Johnstone), 29 = Tani, 30 = Pisang Lilin, 31 = Poteau Geant, 32 = Pisang Klutuk Wulung, 33 = Garbon 2, 34 = Zebrina (G.F), 35 = Khae (Phrae), 36 = Dole, 37 = Wompa, 38 = Pisang Palembang, 39 = Pisang Awak, 40 = Williams (Bell, South Johnstone), 41 = Plantain No.17, 42 = Kluai Tiparot, 43 = Tiau Lagada, 44 = Niyarma Yik, 45 = Selangor, 46 = Long Tavoy, 47 = Malaccenesis, 48 = Figure Pomme Geante, 49 = Highgate, 50 = Borneo, 51 = Honduras, 52 = Pome, 53 = Kunnan, 54 = Musa beccarii, 55 = Musa coccinea, 56 = JD Yangambi,
