Musa Varieties Research Articles

Assessment of metabolic variability and diversity present in leaf, peel and pulp tissue of diploid and triploid Musa spp.

Banana (Musa spp.) plants produce many health promoting compounds in leaf, peel and pulp. For a robust metabolic analysis of these tissues, leaf at five developmental stages were compared to assess suitable sampling practices. Results confirmed that the common sampling practise of leaf 3 is applicable for metabolic comparisons. The developed work flow was applied to analyse the metabolite diversity present in 18 different Musa varieties, providing baseline levels of metabolites in leaf, peel and pulp tissue. Correlation analysis was then used to ascertain whether similar trends can be detected in the three plant tissues of the diversity panel. The genome group displayed a dominant role in the composition of the metabolome in all three tissues. This led to the conclusion that a correlation between tissues was only possible within a genome group as the different parental backgrounds caused too great a variation in the metabolomes. It also suggests the metabolome could be used to monitor the interaction/hybridisation of genomes during breeding programmes.

Molecular and morphological characterization of Musa spp. (Zingiberales : Musaceae) cultivars.

Objectives: The overall goal was to analyze genetic diversity in cultivars of Musa acuminata (Colla) and M. balbisiana (Colla), commonly grown in farms from Caldas department. Scope: Characterization of the genetic variability, at the molecular and morphological level of cultivars of M. acuminata and M. balbisiana, found in farms from Caldas farmers using morphological descriptors and fluorescent microsatellites. Methodology: Phenotyping evaluations comprised 57 morphological characters following the descriptors proposed by IPGRI for the Musa genus, and for genotyping evaluations, nine fluorescent microsatellites (Simple Sequence Repeats-SSR) were used to allow the precise identification of alleles. Additionally, cluster analyses were carried out independently for both morphological and genotypic characterizations under Principal Component Analysis (PCA) and Bootstrapping methods respectively. Main results: Positive and negative highly significant correlations were found for the morphological descriptors, where traits such as presence/ absence of male bud was the rule, as well as the diameter and perimeter of this trait, plus the diameter and perimeter of the peduncle, number of fruits, pseudostem height and fruit length contributed considerably to the variability among the cultivars allowing the discrimination of three main groups in the cluster analyzes. From the molecular perspective a total of 72 polymorphic alleles were obtained, with an average genetic diversity of 0,79, polymorphic information content (PIC) of 0,77 and heterozygosity of 0,48, showed a moderate degree of genetic differentiation (FST = 0,061) among Musa cultivars, generating three main sub-clusters based on their genetic dissimilarity. Conclusions: The identification of certain morphological traits showed to be suitable for the discrimination of Musa cultivars evaluated here. On the other hand, molecular characterization allowed to establish the genetic relationships among groups, also fluorescent SSR were highly informative and accurate, in such a way that can be considered suitable for characterizations in Musa varieties.

Efficient regeneration and genetic transformation platform applicable to five Musa varieties

Background Banana (Musa spp.) is an important staple food, economic crop, and nutritional fruit worldwide. Conventional breeding has been seriously hampered by their long generation time, polyploidy, and sterility of most cultivated varieties. Establishment of an efficient regeneration and transformation system for banana is critical to its genetic improvement and functional genomics.

Efficient regeneration and genetic transformation platform applicable to five Musa varieties

800x600 Background: Banana ( Musa spp.) is an important staple food, economic crop, and nutritional fruit worldwide. Conventional breeding is seriously hampered by their long generation time, polyploidy, and sterility of most cultivated varieties. Establishment of an efficient regeneration and transformation system for banana is critical to their genetic improvement and functional genomics. Results: Herein, a vigorous and repeatable transformation system for banana using direct organogenesis was developed. The greatest number of shoots per explant for all five Musa varieties was obtained using MS medium supplemented with 8.9 μM benzylaminopurine (BA) and 9.1 μM thidiazuron (TDZ). One immature male flower could regenerate 380-456, 310-372, 200-240, 130-156, and 100-130 well-developed shoots in only 240-270 d for Gongjiao, Red banana, Rose banana, Baxi, and Xinglongnaijiao, respectively. Longitudinal sections of buds were transformed through particle bombardment combined with Agrobacterium-mediated transformation using a promoterless β-glucuronidase (GUS) reporter gene; the highest transformation efficiency was 9.81% in regenerated Gongjiao plantlets in optimized selection medium. Transgenic plants were confirmed by histochemical assay of GUS, Polymerase Chain Reaction (PCR), and Southern blot. Conclusions: Our robust transformation platform successfully generated hundreds of transgenic plants. Such a platform will facilitate molecular breeding and functional genomics of banana. Normal 0 21 false false false ES X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";}

Phenylphenalenones protect banana plants from infection by Mycosphaerella fijiensis and are deactivated by metabolic conversion.

Phenylphenalenones, polycyclic aromatic natural products from some monocotyledonous plants, are known as phytoalexins in banana (Musa spp.). In this study, 1H nuclear magnetic resonance (NMR)‐based metabolomics along with liquid chromatography and mass spectrometry were used to explore the chemical responses of the susceptible ‘Williams’ and the resistant ‘Khai Thong Ruang’ Musa varieties to the ascomycete fungus Mycosphaerella fijiensis, the agent of the black leaf Sigatoka disease. Principal component analysis discriminated strongly between infected and non‐infected plant tissue, mainly because of specialized metabolism induced in response to the fungus. Phenylphenalenones are among the major induced compounds, and the resistance level of the plants was correlated with the progress of the disease. However, a virulent strain of M. fijiensis was able to overcome plant resistance by converting phenylphenalenones to sulfate conjugates. Here, we report the first metabolic detoxification of fungitoxic phenylphenalenones to evade the chemical defence of Musa plants.

Rapid, specific, simple, in-field detection of Xanthomonas campestris pathovar musacearum by loop-mediated isothermal amplification.

To develop and evaluate a loop-mediated isothermal amplification (LAMP) assay for Xanthomonas campestris pathovar musacearum (Xcm), the causal agent of banana Xanthomonas wilt, a major disease of banana in Africa. LAMP primers were designed to the general secretion pathway protein D gene and tested against 17 isolates of Xcm encompassing the known genetic and geographic diversity of the bacterium and all isolates were detected. Seventeen other Xanthomonas isolates, including closely related Xanthomonas vasicola, other bacterial pathogens/endophytes of Musa and two healthy Musa varieties gave negative results with the LAMP assay. The assay showed good sensitivity, detecting as little as 51fg of Xcm DNA, a greater level of sensitivity than that of an Xcm PCR assay. Amplification with the LAMP assay was very rapid, typically within 9min from bacterial cultures. Symptomatic field samples of Musa from Uganda were tested and all produced amplification in less than 13min. The LAMP assay provides rapid, sensitive detection of the pathogen that is ideally suited for deployment in laboratories with basic facilities and in-field situations. This is the first LAMP assay for Xcm which provides a significant improvement compared to existing diagnostics.

Structure−Activity Relationship in the Interaction of Substituted Perinaphthenones with Mycosphaerella fijiensis

The levels of native fungitoxic perinaphthenone phytoalexins in susceptible Musa varieties (banana), which are commercially grown in large plantations, are too low to provide plants with long-lasting protection against highly pathogenic fungi. Novel strategies for plant protection are necessary to reduce crop losses and to prevent the development of resistant fungal strains. The synthesis of novel fungicides based on the structures of perinaphthenone natural products is considered to be a promising strategy. Thirteen substituted perinaphthenones, among them two known natural products (1, 2) and 11 synthetics (3-13), were evaluated for their activity against Mycosphaerella fijiensis , and their half-maximal inhibitory concentrations (IC(50)) were calculated to establish structure-activity relationships (SAR). A SAR trend was hypothesized, leading to the design of a new compound, 4-methoxy-2-nitro-1H-phenalen-1-one (14); the new compound displayed significantly enhanced in vitro activity against M. fijiensis compared to other perinaphthenone derivatives. The activity of 14 was comparable to that of two commercial fungicides.

Antinutrients and heavy metals in new NigerianMusahybrid peels with emphasis on utilization in livestock production

Introduction. A comparative study of antinutrients and heavy metals in the peels of five improved varieties of plantain and banana hybrids was investigated. Our aim was to provide information on plantain and banana peels that may circumvent huge losses during fruit processing by converting waste into wealth and health. Materials and methods . Four new plantain hybrids developed at the IITA, Nigeria, named PITA 14, PITA 17, PITA 24 and PITA 26, one cooking banana hybrid (BITA 3) and an African plantain landrace, Agbagba, were investigated. Antinutrient and heavy metal contents of the dried peels from the different cultivars were determined and the data were statistically analyzed. Results and discussion . The plantain hybrid PITA 14 differed significantly from other cultivars in saponin, tannin and oxalate. A significant difference was observed between PITA 17 in phytate compared with other cultivars. Cyanogenic glucosides found in PITA 17, PITA 26 and BITA 3 differed significantly from the values obtained in other cultivars. Both BITA 3 and Agbagba are significantly different from other cultivars in phenolic content, while PITA 24 and Agbagba differed significantly from other cultivars in lead. PITA 24 peels differed significantly from other cultivars in cadmium, but no significant difference was found among the different Musa varieties in mercury. Conclusion . In spite of the antinutritional properties ascribed to the various constituents investigated, the levels found in the peels of new Musa hybrids suggest that new varieties might not constitute a health hazard when ingested. Plantain and banana peels may be converted into livestock feeds, which will eventually provide protein and other nutrients to humans from consumption of meat and other products derived from the animals.

Sampling Strategies and Variability in Fruit Pulp Micronutrient Contents of West and Central African Bananas and Plantains (Musa Species)

The variability in fruit micronutrient contents in a selection of Central and West African Musa varieties cultivated under standardized field conditions was studied. Analysis of the within-fruit, within-hand, and within-plant as well as the between-plant variations demonstrated that both provitamin A carotenoids (pVACs) and mineral micronutrient (Fe, Zn) contents vary significantly across all sample groups. The variations in pVACs contents appear to be at least partly related to differences in the developmental status of the fruit, but the observed trends were genotype-specific. The mean pVACs concentrations per genotype indicated that there is substantial genetic variation in the fruit pVACs contents between Musa cultivars, with orange-fleshed plantain varieties (AAB) having generally higher fruit pVACs contents than dessert bananas (AAA). It was not possible to identify consistent trends between the sampling position and fruit Fe/Zn contents. Once the within-bunch micronutrient variability has been accounted for, the mean variations in fruit micronutrient contents between individual plants of a variety generally fell to within acceptable limits. Results are discussed within the framework of standardizing sampling and developing strategies to screen for the nutritional values of new and existing Musa varieties.

In vitro screening for resistance to Radopholus similis in Musa spp.

The burrowing nematode, Radopholus similis, is the most important nematode pest of banana and plantain worldwide, causing severe yield losses in commercial and local consumption cultivars. Chemical control is currently the most-used method to manage the nematodes, although nematicides are dangerous, toxic and expensive. Therefore, nematode control through genetic improvement is widely encouraged. Protocols have been set up to detect sources of resistance in the existing Musa germplasm, but the screening under greenhouse and field conditions is laborious and time consuming. In vitro screening could facilitate this process by picking up sources of resistance at an early phase. In this study, a procedure for in vitro screening for the resistance to R. similis was set up by determining the optimal incubation time and the optimal nematode inoculum. In a second step, the optimized procedure was confirmed by screening a selection of Musa varieties with a known host plant response. Except for ‘Yangambi Km5’, their host response under in vitro conditions corresponded to their host response under greenhouse or field conditions. The susceptible status of ‘Grande Naine’, ‘Gros Michel’ and ‘Cachaco’ was confirmed, as well as the resistant status of ‘Pisang Jari Buaya’ and ‘SH-3142’.