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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

The Yellow Scare: Developing <i>Bananapocalypse</i> from the Page to the Stage

Clark, David W. 01 May 2011 (has links)
This thesis presents the written documentation and evaluation of the development of the original play Bananapocalypse from conception to realized production at Southern Illinois University Carbondale. I wrote this play to exist as a unique, live theatrical experience that utilizes the theatre audience in ways that other media, such as television and film, simply cannot, but doing so in a potent and purposeful way connected to the play's plot and ideas. In doing so, I wrote a play that existed to primarily be a comedy, using its humor to reflect on our society and satirically to poke holes in our national identity. Chapter One is a detailed exploration of the play's origins, plot and character creation, goals of the production, and script development through its selection as part of the 2010-2011 Season. Chapter Two discusses the production process, following the play's continuing evolution as it was brought to the stage in collaboration with a director, actors, and designers. Chapter Three focuses entirely on the audience, detailing their reactions to the play in performance. Chapter Four serves as my evaluation of the process, the performance, and the audience reaction, discovering what these aspects and my journey says about the play and how it needs to further develop. The final chapter is the production draft of the full play script. Recording of original music is included in supplementary material.
42

Efeito da radiacao gama em properiedade da farinha de banana verde / Effect of gamma radiation in properties of green banana flour

UEHARA, VANESSA B. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:09Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:17Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
43

Efeito da radiacao gama em properiedade da farinha de banana verde / Effect of gamma radiation in properties of green banana flour

UEHARA, VANESSA B. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:33:09Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:17Z (GMT). No. of bitstreams: 0 / O amido de bananas tem sido pesquisado na área de nutrição a partir da introdução do conceito de Amido Resistente (AR). O amido de Musa AAA-Nanicão e Musa AAB-Terra já foram caracterizados quanto as suas respostas fisiológicas. A banana verde possui boa quantidade de amido resistente. O principal interesse em relação ao amido resistente é o seu papel fisiológico. Por não ser digerido no intestino delgado, este tipo de amido se torna disponível como substrato para fermentação pelas bactérias anaeróbicas do cólon Dessa forma, essa fração compartilha muitas das características e benefícios atribuídos à fibra alimentar no trato gastrintestinal. O processo de irradiação por radiação gama pode causar uma variedade de modificações nas macromoléculas, algumas de aplicação industrial, como é o caso de perda de viscosidade e alteração de textura. No presente trabalho, farinhas de banana verde (FBV) de duas origens, foram utilizadas para estudar a sensibilidade a radiação por meio de medidas de viscosidade, textura, colorimetria e pH. As amostras de farinha de banana verde foram irradiadas com raios gama em doses de 0 a 10 kGy e taxa de dose em torno de 2kGy/h. As soluções de FBV apresentaram-se como fluidos não-newtonianos, A irradiação não alterou significativamente o pH dos hidrogéis das farinhas de banana verde FBV1 e FBV2. A viscosidade, de maneira geral, diminuiu com a dose de radiação aplicada. Quando analisada a textura a força máxima de ruptura dos hidrogéis de FBV1 e FBV2 decresceu conforme aumento da dose de irradiação. Entretanto, em particular quando irradiada a dose de 3 kGy, a FBV2 apresentou força de ruptura aumentada. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
44

The prevention of postharvest heat and chilling injury in bananas.

De Villiers, Bernard Johann 17 April 2008 (has links)
Seasonal variations had a great influence on the ripening patterns of banana fruit. Normal ripening was enhanced or delayed by the effect of the maturing season on the fruit. Fruit maturing in summer (harvested in autumn) showed an increase in the rate of ripening, while fruit harvested in winter and spring showed a decrease in the rate of ripening. The banana fruit are sensitive to temperatures outside of their acclimated range. Due to ineffective storage and faulty handling procedures, cold and heat stress is a universal problem in bananas. Large amounts of fruit are lost due to heat and cold stress. Chilling injury occurs when bananas experience or are stored at temperatures below 13C, for a few hours to a few days. Temperatures slightly above 30C may cause extensive heat damage. The three main mechanisms suggested for the prevention of chilling and heat injury are the synthesis of small heat shock proteins, changes in the saturation of fatty acids of the membranes and suppression of the ethylene production and respiration rates. The prevention of cold and heat stress is investigated by monitoring the effect of short-term heat treatment and treatment with ethylene inhibitors on the ripening of the fruit. To determine changes in ripening the following eight ripening parameters are monitored: Yellowing, firmness of the pulp, sugar concentration, starch content, ethylene synthesis, respiration rate, rate of moisture loss and ion leakage. It was found that 1-methylcyclopropene (1-MCP) alleviates the symptoms of heat injury up to a point, but the symptoms of chilling injury were not affected. The effects of the three temperatures investigated: 35°C, 40°C and 45°C for different times. A short pre-heat treatment of 35˚C for 20 minutes proved successful to delay the ripening of the banana fruit, but did not protect the fruit against heat or chilling injury. The results of this study clearly indicate that both chilling and heat injury involve the action of ethylene and suggested that longer exposures to 1-MCP may be effective in preventing both types of injury. / Prof. C.S. Whitehead
45

Social capital and technology adoption on small farms : the case of banana production technology in Uganda

Katungi, Enid Mbabazi 15 May 2007 (has links)
In recent years, development practitioners and policy makers have increasingly become interested in social capital as an additional instrument for economic development. However, within the applied economics literature on the adoption of agricultural technologies, research on the role of social capital in adoption decision-making is scant. Furthermore, there is a paucity of information regarding the determinants of social capital accumulation among rural households in developing economies. This study examines the nature of the relationship between social capital and crop management decisions of Ugandan banana farmers. This dissertation develops a model of technology adoption that incorporates social capital and offers two explicit mechanisms through which social capital may influence technology adoption. A model of the agricultural household, which considers the effects of incomplete markets in farm production decisions, provided the theoretical framework for an econometric analysis to predict the choice and demand of improved banana management technology. The core theoretical framework was extended by explicitly incorporating social capital as a component of exogenous income and information accumulation processes. Empirical analysis was based on the primary data collected in a survey of 400 banana-producing households in Uganda through face-to-face interviews with the primary production decision makers. The households were selected from the three major banana-producing regions of Uganda using multi-stage random sampling methods. A combination of econometric methods was employed. A Probit model was used to estimate the probability of using an improved banana management practice and participation in an association. The extent of use of improved banana management practices was estimated by two methods, namely, ordinary least squares (OLS) and the Heckman procedure to account for sample selection in some equations. Intensity of participation in associations was estimated with a Poisson model. A negative binomial model that allows for over dispersion in the data was employed to identify the determinants of the intensity of participation in private social networks. The results of the study indicate that different aspects of social capital shape the decision to use and the extent of use of an improved management practice, but the nature of effect is specific to the practice as well as the form of social capital. Participation in associations and the characteristics of those associations are important determinants of banana production management decisions. Participation in associations and private social networks is, in turn, influenced by household wealth, education, institutional environment, and social heterogeneity of the community. Aside from social capital, other factors that are significant in explaining variation in use of improved crop management practices among farmers have been identified. Market incentives and household factor endowments were the most important of these factors in decisions regarding use of improved banana management practices. The existence of separability between consumption and production decisions, a major analytical feature of the model of the agricultural household, also appears to be practice-specific, which suggests that production orientation is associated with the use of practices. / Thesis (PhD (Agricultural Economics))--University of Pretoria, 2007. / Agricultural Economics, Extension and Rural Development / unrestricted
46

Host-endophyte-pest interactions of endophytic Fusarium oxysporum antagonistic to Radopholus similis <i/>in banana (Musa spp.)

Athman, Shahasi Yusuf 07 December 2006 (has links)
Radopholus similis is one of the key pests of banana in the East African Highlands and in the world. Although control of this pest has mainly relied on the use of clean planting material, re-infestation of plants in the field remains a critical concern. Alternative management options such as the use of fungal endophytes may be used to provide protection and extend plant life. In this study, a total of 35 endophytic Fusarium isolates were screened for the production of secondary metabolites antagonistic to R. similis in culture. Undiluted and diluted culture filtrates were tested against motile stages of R. similis and eggs. Tests were conducted using culture filtrates of the fungal isolates grown in banana corm broth. All isolates tested demonstrated some level of in vitro antagonistic activity on the mobility of R. similis mixed stages (males, females and juveniles). The percentage of immobilized nematodes increased with increase in the length of exposure time to culture filtrates. After 24 hrs exposure, up to 100% of nematodes were immobilized compared to 26.5% in control treatments. Mortality of mixed stages of R. similis exposed to culture filtrates for 24 hrs, followed by rinsing with sterile distilled water, demonstrated that the effects of culture filtrate treatment were irreversible, as nematodes did not recover and were considered dead. Nematode mortality rates after 24-hr exposure periods ranged from 76.4% to 100.0%. The effects of culture filtrates on R. similis motile stages increased with increasing culture filtrate concentration. Culture filtrates also demonstrated inhibitory effects on hatching of R. similis eggs. Radopholus similis males were more sensitive to culture filtrate treatment than females. The results obtained demonstrate the potential for using endophytic Fusarium isolates as biological control agents against R. similis and/or toxic derivatives as potential nematicides against the nematode. / Thesis (PhD (Plant Pathology))--University of Pretoria, 2006. / Microbiology and Plant Pathology / unrestricted
47

The development of a trickle irrigation system for banana (Musa spp.) production in St. Lucia.

Madramootoo, Chandra Alastair, 1954- January 1981 (has links)
No description available.
48

The role of meta-topolins on the physiology of micropropagated 'Williams' bananas (Musa spp. AAA)

Aremu, Adeyemi Oladapo. January 2012 (has links)
Banana production ranks fifth behind cereals as a food crop and has potential, along with other major crops, to feed the world's increasing population. Globally, continuous efforts and techniques including the use of plant tissue culture (PTC) have been devised for increasing the production of several Musa species. The choice of cytokinin (CK) is one of the most critical factors in developing a successful PTC protocol. Since the discovery of topolins as naturally occurring aromatic CKs, they have emerged as genuine alternatives to the long serving CKs (benzyladenine = BA, zeatin = Z and kinetin = KIN) in PTC. Globally, the past 15 years has witnessed a surge in the use of topolins and their derivatives in research laboratories. Topolins have demonstrated great potential during culture initiation and protocol optimization as well as for counteracting various in vitro induced physiological disorders in some species. In terms of general physiology (growth, phytochemical and photosynthetic pigment contents as well as genetic fidelity), the topolins were compared with BA using 'Williams' bananas with minimal residual exogenous CK carry-over effects. The five topolins tested were meta-Topolin (mT); meta-Topolin riboside (mTR); meta-Methoxy topolin (MemT); meta-Methoxy topolin riboside (MemTR) and meta-Methoxy topolin 9-tetrahydropyran-2-yl (MemTTHP). Based on evidence of potential CK- and auxin-like activity of smoke-water (SW) and karrikinolide (KAR1) at low concentrations, a similar comparative study involving both compounds and mT was performed. For a further understanding of banana physiology in vitro, the effect of supplementing either mT- or BA-requiring cultures with roscovitine (a cyclin-dependent kinase and N-glucosylation inhibitor) and INCYDE (an inhibitor of CK degradation) on the endogenous CK profiles was investigated. In addition, greenhouse experiments geared towards improving the acclimatization competence of tissue-cultured banana plantlets via application of different concentrations of SW and vermicompost leachate was conducted. Sterile shoot-tip explants were cultured on modified Murashige and Skoog (MS) media supplemented with 10, 20 or 30 μM of the tested CKs for 42 days while rooting experiments involved the use of classic auxins as well as SW and KAR1. Apart from 10 μM BA and 30 μM MemTTHP treatments, the number of shoots produced with all the CK treatments were significantly higher than the control. Treatment with 30 μM mT resulted in the highest number of shoots (7.3±1.0) which is an indication of the requirement of exogenous CK for increased shoot proliferation in 'Williams' bananas The use of 10 μM MemTTHP had the least root inhibitory effect during the shoot proliferation phase. As an indication of the toxicity of applied CK, MemT- and MemTR-regenerants were the most deformed while mTR-regenerated plantlets demonstrated the best quality across all the CKs tested. In mT- and BA-derived shoots, SW and KAR1 significantly increased the number and length of roots compared to the control. During the rooting phase, topolin treatments produced more off-shoots than BA-treated ones which inevitably improved the overall number of regenerated shoots. Total phenolic levels were highest in 10 μM mT- and 30 μM MemTTHP-treated plantlets detected in the aerial and underground parts, respectively. It is interesting that in the underground parts, 10 μM mT resulted in the production of the highest amount of proanthocyanidins which was approximately five-fold higher than in the control plants. On the other hand, 10 μM MemTTHP-treated plantlets had significantly higher total flavonoids within the aerial parts. In view of the stimulation of secondary metabolites in the majority of the CK-treated plantlets, the current results indicate the role of the type and concentration of applied CK as potential elicitors in PTC. Generally, the maximum photosynthetic pigment content was attained between 40-50 days. The control plantlets had the highest pigment content (1150 μg/g FW) while 10 μM MemTTHP had the best pigment stimulatory effect among the tested CKs. Nevertheless, in vitro propagation of banana devoid of CKs is not a practical option due to low shoot proliferation rates. Scanning electron microscopy (SEM) of the foliar surface showed that the stomatal density was highest in 10 μM MemTTHP-treated and lowest in 10 μM MemTR-treated plantlets. Prolonging the culture duration as well as increasing CK concentrations reduced the pigment content. However, the drastic breakdown in chlorophyll pigments beyond 50 days was slightly inhibited by the presence of mT, mTR, MemTTHP and BA compared to the control. Current findings indicate the potential anti-senescence activity of the topolins such as mT, mTR and MemTTHP under in vitro conditions. This study articulates that the right choice and concentration of CKs applied during in vitro propagation may alleviate photomixotrophic-induced physiological stress that usually accompanies the transfer of plantlets to ex vitro conditions. Findings indicate that the effect of subculturing contributed significantly to the higher rate of variation in 'Williams' bananas in vitro. The presence of CK in the culture media apparently aggravated the stress on the explants as indicated in the relatively higher percentage polymorphic bands compared to the controls. Among the tested CKs, the use of mTR and MemTTHP caused the least detrimental effect on the regenerants while mT-treated plantlets had the most polymorphic bands. Hence, it is recommended that subculturing cycles from the initial explant establishment should be limited to a maximum of five. The use of SW and KAR1 improved the level of photosynthetic pigment and phenolic compounds in the micropropagated bananas. However, they had a negative effect on shoot proliferation; hence their inclusion is more desired when used at the rooting phase of micropropagation. Perhaps, these compounds could be used in conjunction with auxin to increase the number of roots prior to the acclimatization stage. The enhanced photosynthetic pigment level resulting from addition of SW and KAR1 would also play a vital role during acclimatization of the micropropagated plants. The present finding serves as an alternative approach, available to researchers for improving the quantity of secondary metabolites in micropropagated plants. The highest regeneration rate (93%) was observed in BA + roscovitine treatment while mT + INCYDE-treated plantlets produced most shoots. Treatment with BA + roscovitine had the highest shoot length and biomass. Although not significant, there was more proanthocyanidins in BA + roscovitine treatments compared to the treatment with BA alone. On the contrary, total phenolics were significantly higher in mT + roscovitine treatment than in the mT-treated regenerants. The presence of roscovitine and/or INCYDE had no significant effect on the photosynthetic pigments of the banana plantlets. Forty-seven aromatic and isoprenoid CKs categorized into nine CK-types were detected at varying concentrations. The presence of mT + roscovitine and/or INCYDE increased the levels of O-glucosides, while 9-glucosides remained the major derivative in the presence of BA. Generally, the underground parts had higher CK levels than the aerial parts; however the presence of INCYDE increased the level of CK quantified in the aerial parts of both CK treated plantlets. Apparently, the presence of INCYDE serves to enhance transportation of the CK towards the aerial regions. From a practical perspective, the use of roscovitine and INCYDE in PTC could be crucial in the alleviation of commonly observed in vitro-induced physiological abnormalities. Soil drenching with SW significantly increased the root length (1:1000 and 1:500 dilutions) as well as fresh and dry weight (1:1000; 1:500 and 1:250 dilutions) when compared to foliar application. Vermicompost leachate (1:10 and 1:5 dilutions) significantly enhanced the shoot length, root length, leaf area and dry weights. Vermicompost leachate (1:20; 1:10 and 1:5 dilutions) also significantly increased the number of off-shoots. The positive effect on rooting is beneficial for acclimatization and establishment of tissue-cultured banana plantlets in nurseries and subsequent transfer to the field. However, field trials will be necessary to substantiate the effects demonstrated by these compounds. In an attempt to contribute to improving banana micropropagation, the current findings provide additional evidence on the increasing advantage of topolins over BA. Nevertheless, some detrimental physiological effects observed with some of the topolins (for example, MemT and MemTR) are clear indication that they should not be taken as a panacea in PTC. Besides optimizing efficient PTC protocols through stringent choice of CKs, other associated physiological and metabolic events taking place in culture during the optimization process need more in-depth investigation. In addition to contributing towards the better understanding of the mode of action of these CKs, such an approach will help solve associated physiological and developmental problems in vitro. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.
49

Agrobacterium tumefaciens-mediated transformation of Fusarium oxysporum f. sp. cubense for pathogenicity gene analysis

Meyer, Tanja 12 June 2009 (has links)
Fusarium wilt of banana, caused by Fusarium oxysporum f. sp. cubense (Foc), is one of the most destructive plant diseases in recorded history. The disease was first discovered in Australia in 1874 but became renowned for the severe losses it caused to export banana plantations during the 1960s in Central America. The banana export industry was saved only by replacing Gros Michel bananas, the dessert banana grown for the export market, with highly resistant Cavendish banana cultivars. Despite this apparent solution, the fungus was found to attack Cavendish bananas in the sub-tropics, where plants were believed to be predisposed to the disease by the cool winter climate. Good management practices and conventional disease management strategies have not been sufficient to reduce losses and stop the disease from spreading, and today Fusarium wilt can be found in almost all banana-producing countries of the world. Since 1988, Foc has been responsible for significant losses of Cavendish bananas in tropical Asia. The only sustainable control measure, the use of resistant varieties, is not always popular as people prefer to eat locally adopted varieties that, unfortunately, are susceptible to Foc. Sustainable Fusarium wilt management in banana depends on the improvement of existing banana cultivars or the development of novel disease management strategies. Molecular biology and biotechnology provide opportunities to introduce foreign resistance genes into existing cultivars and to develop new, environmentally friendly products that can protect susceptible bananas from Foc. Better knowledge of the Fusarium wilt pathogen, its diversity, and its mechanisms of pathogenesis will contribute significantly to developing these novel approaches for control of the disease. Molecular information on the pathogenicity of Foc, however, is limited, whereas other formae speciales of F. oxysporum have been better studied. In this thesis, Agrobacterium tumefaciens-mediated transformation of (ATMT) was employed to investigate genes responsible for pathogenicity of Foc to banana. Chapter 1 provides an overview of pathogenicity in F. oxysporum. Pathogenic and non-pathogenic forms of the fungus are first introduced to the reader, and then the biology, epidemiology and etiology of pathogenic forms of F. oxysporum are discussed. The genetic make-up and ability of the Fusarium wilt fungus to cause disease in plants concludes the first part of the review. In recent years, there has been a noted increase in the number of techniques available to study hostpathogen interactions. The second part of the review concentrates on these techniques and their applications in studying pathogenicity of the Fusarium wilt pathogen. In Chapter 2, an ATMT and screening system for Foc was developed. Five A. tumefaciens strains were evaluated for their efficiency to transform Foc with a randomly integrating vector that confers hygromycin B resistance and expression of green fluorescent protein (GFP). A small insertion mutant library of Foc was created, and a subset of transformants was characterized by determining the number of T-DNA inserts present, the location and identity of predicted genes disrupted by T-DNA insertion, and whether transformants of Foc were altered in their virulence against susceptible banana plants. In Chapter 3, the role of a known pathogenicity gene, Frp1, of the tomato pathogen F. oxysporum f. sp. lycopersici (Fol) was investigated in Foc. The first objective was to isolate and characterize the Frp1 gene in Foc, and to compare it to the homologous gene in Fol. A vector containing a modified Fol Frp1 gene was then obtained and used for targeted disruption of the gene in Foc via ATMT. Mutants in which the Frp1 gene was disrupted were then analyzed for GFP expression, culture morphology, and alterations in pathogenicity to banana. / Dissertation (MSc)--University of Pretoria, 2008. / Microbiology and Plant Pathology / unrestricted
50

Breeding investigations for black Sigatoka resistance and associated traits in diploids, tetraploids and the triploid progenies of bananas in Uganda.

Barekye, Alex. January 2009 (has links)
Reduced banana yield owing to black Sigatoka Mycosphaerella fijiensis Morelet is a threat to the livelihoods of Ugandan subsistence farmers who depend entirely on the banana crop for food security. The objectives of this investigation were to: (i) assess farmers’ knowledge of black Sigatoka disease in central Uganda; (ii) document the qualities farmers would desire in the banana genotypes to be developed for black Sigatoka resistance; (iii) appraise the methods for assessing black Sigatoka resistance in diploid banana populations; (iv) determine the phenotypic variation for black Sigatoka resistance and agronomic traits in diploid and tetraploid bananas; (v) determine the influence of tetraploid and diploid parents on the black Sigatoka resistance and agronomic traits in the triploid progenies; and (vi) evaluate 2x by 2x banana progenies for yield and black Sigatoka resistance. A survey that focused on low and medium banana production zones in Uganda established that there was limited awareness of black Sigatoka disease as a constraint on banana production in the areas surveyed. It was also established that farmers liked local bananas because of their superior taste, early maturity, and marketability. There were farmers who had been exposed to new black Sigatoka resistant materials but never liked these new banana materials because of poor taste and lack of market. Farmers desired new banana materials with good taste on cooking, heavy bunches, resistance to pests and diseases, drought tolerance, and early maturing capacity in that order. The results indicated that the banana farmers in Uganda attached more importance to food quality attributes than to production attributes especially when considering new banana materials. This suggested that farmers mainly grow bananas for consumption. Three black Sigatoka assessment methods, youngest leaf spotted, disease development time and area under disease progress curve (AUDPC) were appraised using a diploid population. All the three methods were able to classify the diploid accessions into resistant and susceptible clones. The cultivar rankings of AUDPC correlated strongly with the rankings of disease development time. The cultivar rankings of AUDPC correlated positively with the rankings of youngest leaf spotted method. The youngest leaf spotted at flowering and AUDPC predicted significantly total number of leaves at flowering (R2 = 0.53). Overall AUDPC had the highest coefficient of determination (R2=0.84) in assessment of banana diploids for black Sigatoka resistance indicating that it accounted for the highest variation in disease response observed among the diploid clones. From this investigation it was recommended that AUDPC should be used to assess resistance on black Sigatoka in Musa species. A phenotypic analysis on the diploid and synthetic tetraploids, and a molecular analysis using RAPD markers on the tetraploid population were conducted. Results indicated that the diploid population had significant (P<0.001) variation for plant height, plant girth, days from flowering to harvest, bunch weight, number of suckers, youngest leaf spotted, total leaves at flowering, area under disease progress curve, and number of functional leaves at harvest. Principal component analysis showed that plant height and girth explained most of the variation observed in the diploid population. In the tetraploid population, significant differences were observed for plant height, plant girth, and number of suckers (P<0.05). In the tetraploids principal component analysis, indicated that youngest leaf spotted and total leaves at flowering had higher loadings on principal component one. Genetic distances computed from RAPD markers indicated limited genetic variability in the tetraploid population. Another investigation was also carried out to determine the influence of tetraploid and diploid parents on black Sigatoka resistance and agronomic traits in the triploid progenies generated from tetraploid-diploid crosses. The results indicated that diploids transferred black Sigatoka resistance to triploid progenies as measured by disease development over time, the number of functional leaves at flowering and at harvest. On the other hand, the female synthetic tetraploids influenced plant height and bunch weight in the triploid progenies generated from tetraploid-diploid crosses as observed from triploid progeny correlations and parent-offspring regressions. Therefore, it is important to select tetraploids with heavy bunch weights to generate high yielding triploids in tetraploid-diploid crosses. Lastly, this thesis investigated the relationship between bunch weight and black Sigatoka resistance traits in 2x by 2x progenies generated using a random polycross design. Phenotypic correlations revealed strong positive relationships between bunch weight with total leaves at flowering, youngest leaf spotted, plant girth, and days from planting to flowering among the 2x by 2x progenies. Linear regression analysis indicated that girth, total fingers and finger length significantly predicted bunch weight (R2=0.67). However, days from planting to flowering, and total leaves at flowering had strong indirect effects on bunch weight via plant girth. The results imply that selection for parents with good combining ability for girth, finger length and total fingers can improve bunch weight in a diploid population. / Thesis (Ph.D.) - University of KwaZulu-Natal, Pietermaritzburg, 2009.

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