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Sociolinguistics of Lesotho English in the Kingdom of Lesotho
No full textThesis (Ph.D.(Linguistics and Language Practice))--University of the Free State, 2021This study set out to investigate Sociolinguistics of Lesotho English in the Kingdom of Lesotho. Mainly premised on the principles of the qualitative research design and methodology, this study adopted the narrative interviews, rapid and anonymous observations as well as documentary sources for data collection in answer to the research questions. The research questions which this study set out to answer for achieving the research objectives are as follows: Is there any emerging variety worthy of the name Lesotho English (LesE) amongst the Basotho in Lesotho? If any, to what extent is such a variety critical in defining LesE at the levels of phonology, morphosyntax and lexicon? and How does LesE differ from Sub-Saharan Southern African Englishes, particularly Black South African English (BSAE) and/or other World Englishes? With the above questions, the study has, therefore, made general observations of linguisticvariations at the levels of phonology, morphosyntax and lexicon of LesE from both the oral and written data sets for this study.
In particular, using the above-mentioned instruments for collecting oral and written data from the target participants, the study has found systematic salient phonological variations from English which I assume to be BrE. The findings include recurrent spelling pronunciations, syllable-timing, aspiration, missing contrastive stress and syllabic consonants, diphthongal and neutralised vowel sound patterns as well as substitution of interdental fricatives across the oral data on LesE in the context of Lesotho. Further, the morphosyntactic variants discovered from the data comprise the progressive aspect and levelling of the preterite and perfect aspect, the modal system, grammatical and notional concord, relativisation, pronominal appositions, the article system and prepositional usages. Qualitative evidence has thus revealed systematic morphosyntactic variants from the oral and written data for this study, thus highlighting features, possibly unique to LesE and/or comparable to other outer-circle, and, to some extent, inner-circle varieties of English. Similarly, at the lexical level, LesE has been found to bear systematically salient lexical and orthographic variants, coupled with alternative spellings, heteronyms and dehyphenated compound words and sporadic variants of semantic extension. It is, therefore, concluded, in this study, that sociolinguistics of LesE in the Kingdom of Lesotho could be seen as bearing nativised, endonormative and exonormative variations of English, making LesE a comparably emerging English variety to other outer-circle and inner-circle Englishes.
___________________________________________________________________Hierdie studie het ten doel om die Sosiolinguistiek van Lesotho-Engels in die Koninkryk van Lesotho te ondersoek. Hoofsaaklik gegrond op die beginsels van die kwalitatiewe navorsingsontwerp en -metodologie, het hierdie studie die narratiewe onderhoude, vinnige en anonieme waarnemings sowel as dokumentêre bronne vir data-insameling in antwoord op die navorsingsvrae aanvaar. Die navorsingsvrae wat hierdie studie beoog om te beantwoord vir die bereiking van die navorsingsdoelwitte, is as volg: Is daar enige opkomende weergawe wat die naam Lesotho-English (LesE) waardig is onder die Basotho's in Lesotho? Indien enige, tot watter mate is so 'n weergawe krities in die definisie van LesE op die vlakke van fonologie, morfosintaksis en leksikon? En hoe verskil LesE van Suider-Afrikaanse Engels suid van die Sahara, veral Swart Suid-Afrikaanse Engels (SSAE) en/of ander Wêreld-Engels? Met bogenoemde vrae het die studie dus algemene waarnemings gemaak van linguistiese variasies op die vlakke van fonologie, morfosintaksis en leksikon van LesE uit die mondelinge en geskrewe datastelle vir hierdie studie. In die besonder, deur die gebruik van bogenoemde instrumente vir die insameling van mondelinge en skriftelike data van die teikendeelnemers, het die studie sistematiese opvallende fonologiese variasies van Engels gevind, wat ek aanvaar BrE is.
Die bevindinge sluit in herhalende spellinguitsprake, lettergreep-tydsberekening, aspirasie, ontbrekende kontrastiewe spanning en lettergreepkonsonante, diftongale en geneutraliseerde vokaalklankpatrone sowel as vervanging van interdentale frikatiewe oor die mondelinge data oor LesE in die konteks van Lesotho. Verder, die morfosintaktiese variante wat uit die data ontdek is, behels die progressiewe aspek en nivellering van die preteritum en volmaakte aspek, die modale sisteem, grammatikale en nosionele konkord, relativering, pronominale apposisies, die lidwoordsisteem en voorsetselgebruike. Kwalitatiewe bewyse het dus sistematiese morfosintaktiese variante van die mondelinge en geskrewe data vir hierdie studie aan die lig gebring, en sodoende kenmerke uitgelig, moontlik uniek aan LesE en/of vergelykbaar met ander buite-sirkel, en, tot 'n mate, binne-sirkel weergawes van Engels. Net so, op die leksikale vlak, is gevind dat LesE sistematies opvallende leksikale en ortografiese variante dra, tesame met alternatiewe spellings, heteronieme en ontkoppelde saamgestelde woorde en sporadiese variante van semantiese uitbreiding. Daar word dus in hierdie studie tot die gevolgtrekking gekom dat die sosiolinguistiek van LesE in die Koninkryk van Lesotho gesien kan word as 'n plaaslike, endonormatiewe en eksonormatiewe variasie van Engels, wat LesE 'n vergelykbaar opkomende Engelse weergawe maak met ander buite-sirkel en binne- sirkel weergawes van Engels.
___________________________________________________________________Diphuputso tsena di tla batlisisa thuto ya puo ya English ka hara setjhaba sa Lesotho. Mme boithuto bo tla tsepamisa maikutlo hodima boithutotlhalosi le mekgwa ya dipotso tse dumellanang le bopheti kgafetsa, hape bo sebedisa ho shebella ho ikgakantseng hape le ho sebedisa ditokomane e le mokgwa wa ho bokella ditaba tsa phuputso ho tla arabela dipotso tsa diphuputso. Dipotso tse hlophisitsweng ho tla arabelwa ke diphuputso tsena e le ho fihlela sepheo sa tsona ke tse latelang: Na ho na le tse hlahellang tsa bohlokwa tseo ho ka thweng ke English ya Lesotho ka hara setjhaba sa Lesotho? Haeba se le teng, ebe ekaba ke ho isa hokae, haholoholo se buuwang ke batho ba batsho ha kae hoo ho ka thweng ehlile se hlalosa English ya Lesotho (LesE) maeng a thutamedumo, thutamabopi ka hara dipolelo le mabitso? Hape English ya Lesotho (LesE) e ka utlwisiswa ho atamela English ya Sahara, haholoholo e buuwang ke batho ba batsho Afrika Borwa kapa English ya lefatshe? Ka dipotso tse hlano tsa boithuto bona, boithuto bo entse tlhahlobo e akaretsang ka mefuta ya sebopeho sa puo maemong a thutomedumo, mabopi ka hara polelo le mabitso a English ya Lesotho (LesE) bo ipapisitse le puo e buuwang le e ngotsweng ho batalletse boithuto bona mabala. Haholoholo ka tshebediso ya disebediswa tsa diphuputso tse boletsweng ka hodimo ho bokella ditaba ho batho ba bileng le seabo, mme boithuto bo fumane mabopi a fapaneng ho tswa puong ya English ao ke nahanang hore ke BrE. Ditshibollo di fumane hore mongolo, mokgwa wa pitso ya mantswe, dinokonako, manko, bosiyo ba ho hatella / ho toboketsa, le dinokopedi, didumi tse sa utlwahaleng, le didumi tse medumo ya tsona e hlapollotsweng le e kentsweng sebakeng sa mamomaino ka hara ditaba tse buuwang ho English ya Lesotho ka hara Basotho.
Ho feta moo, mabopi a polelo a fapakaneng a sibollotswe ka hara ditaba a kenyelletsa nako, le se nepahetseng sa mokgwa, sebopeho sa puo le ditumela, marui, dihanani tse hlahelletseng, mahlalosi a sebaka le tshebediso ya mahlalosi a sebaka. Nnetefatso ya lehlalosi e nnetefaditse tatellano ya mabopi a polelo a fapaneng ho tswa ho puo e buuwang le puo e ngotsweng bakeng sa boithuto bona, mme ditjhabisa dibopeho, mohlomong tse ikgethang tsa Englishya Lesotho kapa tse ka bapiswang le tse ding tse ka thoko le dibopeho tsa English ya mefuta e meng e ka hare. Ka mokgwa o tshwanang, boemong ba mantswe, English ya Lesotho, e fumanehile e ena le tatellano ya mantswe a thotseng le mongolo o fapaneng o matahaneng le mengolo e mmalwa, e tshwanang le e se nang sehalo tsa mantswe a kopantsweng le tse sa hlahelleng hangata, tsa meelelo e ekeditsweng. Ka hona, ha ho le jwalo, qeto ke hore, boithutong bona, thutapuo ka hara setjhaba ya English ya Lesotho, e ka shejwa e fupere mahalapa ho etswa puo ya lehae, mme hwa ipapiswa le ho amohelwa e le mofuta wa English ya Lesotho e le hore na se buuwa jwang Lesotho e se hore na moo se hlahang teng se buuwa jwang; tse etsang English ya Lesotho e ka bapiswang le English e hlahang e le mofuta o mong o ka ntle ho sedikadikwe le e ka hara sedikadikwe sa dipuo tsa English.
___________________________________________________________________Lolu cwaningo luhlose ukuphenya ngokusetshenziswa kolimi lwesiNgisi emphakathini waseLesotho ebukhosini baseLesotho. Ngokusekelwe kakhulu ezimisweni zomklamo wocwaningo lwekhwalithethivu kanye nendlela yocwaningo, lolu cwaningo lusebenzise izingxoxo ezilandayo, ukuqaphela okusheshayo nokungaziwa kanye nemibhalo njengemithombo yokuqoqa ulwazi ukuze luphendule imibuzo yocwaningo. Imibuzo lolu cwaningo oluhlose ukuyiphendula ukuze kufezwe izinjongo zocwaningo imi kanje: Ingabe kukhona okusafufusa okufanelekile ukubizwa ngesiNgisi saseLesotho phakathi kwaBasuthu eLesotho? Uma kukhona, kubaluleke kangakanani ekuchazeni isiNgisi saseLesotho emazingeni efonoloji, imofosintekthiki kanye nolwazi lwamagama? futhi isiNgisi saseLesotho sihluke kanjani eziNgisini zaseNingizimu Afrikha, ikakhulukazi isiNgisi sabantu Abamnyama baseNingizimu Afrikha kanye/noma esinye isiNgisi emhlabeni wonke? Ngale mibuzo engenhla, ucwaningo lubheke ngokujwayelekile ukuhlukahluka kokusetshenzisa kwezilimi emazingeni efonoloji, imofosintekthiki kanye nolwazi lwamagama esiNgisi saseLesotho kusukela olwazini lomlomo nolubhaliwe. Ikakhulukazi, kusetshenziswa amathuluzi ashiwo ngenhla ukuze kuqoqwe ulwazi lomlomo nolubhaliwe kuba bambiqhaza abaphokophelwe, ucwaningo luthole ukuhlukahluka okuhlelekile kwemisindo ehlukahlukene kusuka esiNgisini engicabanga ukuthi kuyi-BrE. Okutholiwe kuhlanganisa ukuphinyiswa kwesipelingi okuphindaphindiwe, isikhathi sohlamvu, ukuphimisa, ukugcizelela okungafaniyo nongwaqa bamagama, amaphethini onkamisa we-diphthongal kanye namaphethini emisindo yonkamisa abaphinyiswa ngokufana kanye nokufaka esikhundleni samagama athinta emazinyweni kulo lonke ulwazi lomlomo esiNgisini sase-Lesotho esimweni sase-Lesotho.
Ngaphezu kwalokho, ukwahlukahlukana kwemofosintekthiki okutholwe olwazini kufaka phakathi ingxenye eqhubekayo kanye nokulinganiswa kwengxenye yangaphambilini nephelele , isistimu ye-modali, ukuvumelana kohlelo lolimi nencazelo yegama, ukuhlobana , iziqalo zezabizwana, isistimu yegama elichazwayo kanye nokusetshenziswa kwama-preposition. Ngakho-ke ubufakazi bekhwalithethivu buveze ukuhlukahluka okuhlelekile kwemofosintekthiki kusukela olwazini lomlomo nolubhaliwe lwalolu cwaningo, ngaleyo ndlela kugqamisa izici, okungenzeka zihluke esiNgisini saseLesotho kanye/noma eziqhathanisekayo nezinye ezinye iziNgisi zamanye amazwe asebenzisa isiNgisi, futhi, nangezinga elithile, izinhlobo zesiNgisi soqobo. Ngokufanayo, ezingeni lamagama, isiNgisi saseLesotho sitholakale sinezinhlobonhlobo zamagama nobhalomagama ngokuhlelekile, okuhambisana nezinye izipelingi, ama-heteronyms namagama ayingxube angafakiwe uphawu lwe-hyphene kanye nokuhlukahluka okungavamile kokwandiswa kwencazelo yegama. Ngakho-ke kulolu cwaningo kuphethwa ngokuthi, ukusetshenziswa kolimi emphakathini okuyisiNgisi saseLesotho eMbusweni waseLesotho kungabonakala kunezinhlobonhlobo zesiNgisi ezinoguquguquko ngenxa yokungabibikho kwabanikazi bolimi, okwenza isiNgisi saseLesotho sibe uhlobo lwesiNgisi olusafufusa ngokuqhathaniswa nezinye iziNgisi kwamanye amazwe.
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Virtual prospecting in palaeontology using a drone-based orthomosaic map: an eye movement analysis
No full textPaleontological fieldwork is often a time-consuming process and resource intensive. With unexplored and remote areas, the satellite images, geology, and topography of an area are analyzed to help survey for a site. A drone-based orthomosaic map is suggested as an additional tool for virtual paleontology fossil prospecting. The use of an orthomosaic map was compared to the use of a typical satellite map when looking for fossil sites to prospect. Factors were chosen for their impact when prospecting for a fossil site and availability of data. Eye movement data were captured for a convenience sample of paleontologists from a local university. Each band within the satellite map measures 7741 × 7821 with a ground resolution of 30 m/pix, and the ground resolution of the orthomosaic map is 2.86 cm/pix with a resolution of 52,634 × 32,383. Experts displayed a gaze behavior suggestive of high analysis levels as well as being able to identify and analyze features rapidly—this is illustrated through the presence of both longer and shorter fixations. However, experts appeared to look at both maps in more detail than novices. The orthomosaic map was very successful at both attracting and keeping the attention of the map reader on certain features. It was concluded that an orthomosaic-based drone map used in conjunction with a satellite map is a useful tool for high spatial density virtual prospecting for novices and experts.Publisher's versio
Oikos of relational encounters: an Eco-Tourist Visitor’s Centre and Extension to Twinstreams Environmental and Education Centre in the Umlalazi Nature Reserve
No full textIn the time of the Anthropocene, we have reached a point as humans where we have removed ourselves from nature and, in turn, have idealized and romanticised views of our initial natural habitat. We have abandoned our initial biophilic relationship with nature. In the context of the Umlalazi Nature Reserve, the varying levels of our anthropocentric interventions are highly prevalent and serves as a metaphor of our relationship with the environment in the Anthropocene. The landscape is comprised of two prominent manmade forests- a eucalyptus plantation, as well as an indigenous forest that was planted years ago. This relationship, however, exists alongside a myriad of other relations, including spaces of liminality between manmade vehicular roads, a natural stream, a forest, as well as pathways and openings within the forests. It is evident that for our relations with nature to oppose the dominating forces of the Anthropocene, an awareness of the fragility of these relations needs to be stimulated. Professor and philosopher, Timothy Morton’s notion of ‘Dark Ecology’ proposes that, in order for a new ‘ecological awareness’ to emerge, we must abandon the romantic ideals that we have of nature and our surrounding environment. Dark Ecology, alongside principles of biophilic design are investigated throughout this dissertation as a way to recast the romantic expectations we have evolved to possess and stimulate a new form of ‘ecological’ awareness through an ‘oikos’ of relational encounters. This project and dissertation illustrates how the implementation of a biophilic architectural approached, shaped by Dark Ecology, may recast the romantic expectations of nature and stimulate richer relational encounters between the flaneur in the forest within the Anthropocene and eco-tourism industry
Depression and self-regulated learning as predictors of first-year students’ academic performance : a case study
No full textPredictors of first-year students’ academic performance, especially in Science, Engineering and Technology (SET) programmes, are more important now than ever before. Exploring the factors associated with academic success with reference to students’ mental health, as well as certain learning strategy dimensions that have a positive correlation with academic achievement, is an attempt to face the serious challenge of improving student access, success and throughput rates. Thus, the aim of this study was twofold: firstly, to examine depression and self-regulated learning as possible predictors of the academic performance of students in a first-year Biology module at the University of the Free State (UFS) and, secondly, to establish whether depression and self-regulated learning are associated. Furthermore, the researcher compared the influence of depression and self-regulated learning on the academic achievement of students in the access programme to that of students in the mainstream programme of the UFS Faculty of Natural and Agricultural Sciences. A further comparison was made between students in the two programmes in terms of the prevalence of depression and the incidence of the use of self-regulated learning techniques. The results obtained in the present study showed that levels of depression among students in the UFS Faculty of Natural and Agricultural Sciences are of great concern. Furthermore, the results confirmed that certain learning strategy dimensions have a positive correlation with academic achievement. The study also revealed that depression, self-regulated learning dimensions and academic performance are indeed interlinked. However, since depression did not emerge as a significant predictor of academic performance in the final multiple regression model, the study did not prove unequivocally that depression is indeed a predictor of lower academic performance. Nonetheless, a negative correlation between depression and certain selfregulated learning strategies for both the access and mainstream programmes were observed, which therefore indirectly influences the academic achievement of students in both programmes. Lastly, it transpired that mainstream students are not more prone to applying self-regulated learning techniques than those in access programmes. The researcher recommended that the high levels of depression among first-year students in the Faculty of Natural and Agricultural Sciences at the UFS undergo further evaluation and that the problem should be addressed. Self-regulated learning strategies that positively influence academic achievement, as identified in this thesis, should be developed and enhanced among first-year students since studies have shown that learning strategies can be learnt
Exploring the role of principal leadership in Grade 12 learner performance
No full textMany of South Africa’s former disadvantaged schools are now known as no-fee schools. These schools were prioritised as no-fee schools post-1994 in terms of funding because they have the same context and service the poor communities that surround them. Despite similarities of their funding and contextual challenges, these no-fee schools produce varying overall results in the National Senior Certificate (NSC) examinations, which is what triggered this study. The explanation for this poor performance in Grade 12 is still unverified (DBE, 2016:46). It appears as if the learner performance in some of the no-fee schools, which are all located in townships, can be ascribed to the leadership practices of the principals. This study therefore intended to explore principals’ leadership practices at no-fee secondary schools, where good performance is a necessity for survival in future for the learner. The study also intended to investigate the impact the principal’s leadership practices may have on Grade 12 learner performance, specifically in gateway subjects such as mathematics, physical sciences, economics and accounting. Embedded in constructivism, a qualitative research approach with a multiple-case-study research design was employed for this study guided by instructional leadership theory as its theoretical framework and integrated it with other learning theories. Data were gathered through semi-structured interviews with principals and focus group interviews with teachers, all purposefully selected, and some document analysis and observation. The research sites were four township no-fee secondary schools from Emfuleni municipality in Gauteng province. The gathered data were then transcribed, coded into themes and analysed. The findings of the study reflected that no-fee schools have inexperienced principals who are unable to deal effectively with contextual challenges, and minimal parental support, and these factors affect learner commitment and finally compromise good learner performance. The study will be useful and add to the existing body of knowledge on the understanding of the complex leadership roles of principals of no-fee schools. It also revealed the best practices which can be employed by poor-performing principals in order to lead and manage no-fee schools effectively and efficiently and to improve Grade 12 learner performance.University of the Free Stat
Role salience and the growth intention of women entrepreneurs: does work-life balance make a difference?
No full textWork and family are two of the most competing and salient roles in the life of every individual. As such, individuals often make behavioral decisions based on the relative salience (work or family) they attach to these life roles. Given that growth intention is a vital behavioral choice in the life of an entrepreneur, this study examined how role salience influences the growth intentions of women entrepreneurs. Moreover, for most women entrepreneurs, their family domain is highly entwined with the business domain, and as such, having an adequate work-life balance is often a vital personal goal. Thus, this study also examined the influence of work-life balance on the growth intentions of the women entrepreneurs as well as its moderating effect of on the relationship between role salience and growth intentions. Based on self-reported data from women entrepreneurs (N = 300), the findings of this study using logistic regression analysis revealed that both work role salience (b = .88, p < .001) and work-life balance (b = .73, p < .001) have a positive effect on the growth intentions of women entrepreneurs. Additionally, work-life balance also moderated the relationship between work role salience and growth intention such that the positive association is strengthened at high levels of work-life balance (b = .90, p < .001). The study culminates with a discussion of the implications and suggestions for future research.Publisher's versio
Pain, function and health-related quality of life in total knee arthroplasty
No full textIntroduction: Physiotherapists daily treat patients who undergo a total knee arthroplasty (TKA) and find that certain patients tend to function better during their rehabilitation than others. Although it is a successful procedure, some of the patients are not totally satisfied with the outcomes and develop chronic pain and limitations in activities of daily living (ADL). Aim: The aim of the study was therefore to determine the pain intensity, functionality, and health-related quality of life (pre-operatively and post-operatively), in persons undergoing a total knee arthroplasty. Methodology: A prospective cohort analytical study design was utilised. The cohort period was six weeks. Fifty (50) participants participated in this study. All participants were assessed after six weeks by completing several questionnaires and evaluations. Data were analysed by a biostatistician using descriptive statistics; namely, percentages and frequencies for categorical data and means and standard deviations or medians and percentiles for continuous data calculated per collection time point. The change between time points was calculated by means of 95% confidence intervals. Inferential analysis and significance testing was done. Results: There were statistically significant improvements in oedema of the knee, knee extension, average pain experienced daily, pain relief with medication, enjoyment of life, relations with other people, normal work ability, walking ability, mood, total WOMAC (Western Ontario and McMaster Universities Arthritis Index) score and subdivisions and in the Hospital Anxiety and Depression Score (HADS - anxiety and depression). Conclusion: The study describes the characteristics of the individuals who received an elective TKA in a private hospital in Bloemfontein. The importance of physiotherapy management pre-operatively and post-operatively is undeniable, as most of the patients experienced pain and decreased function that impacted their quality of life. Specific recommendations for further research have been put forward as well as clinical recommendations. This is to improve not only the outcomes of a TKA, but also to create awareness amongst physiotherapists regarding the challenges that individuals experience after a TKA and the importance of appropriate and relevant pre-rehabilitation and post-rehabilitation
Polypyridyl copper complexes as dye sensitizer and redox mediator for dye-sensitized solar cells
No full textDevelopments on the application of polypyridyl-based copper complexes in dye-sensitized solar cells (DSSCs) are briefly discussed in this mini review. Copper complexes in solar cells are special in that they can be used either as dye sensitizer and/or as redox mediator (redox couple) in dye-sensitized solar cells (DSSCs). Both the abundance and low cost of copper motivates research on the use of copper complexes, as cheaper and non-toxic alternative to the mostly used iodide/triiodide (I- /I3- ) electrolyte redox couple, and the expensive and rare rutheniumbased dyes of good performance, which currently are best known.Published versio
Genetic analysis of resistance to maize lethal necrosis with emphasis on strategies for improvement of host resistance
No full textMaize lethal necrosis (MLN) is a new disease in Sub-Saharan Africa (SSA) caused by double infection by maize chlorotic mottle virus (MCMV) with any of the many viral agents in the Potyviridae family. It has become one of the key constraints to maize production in the region due to the significant crop losses caused since its emergence in 2011. Sustainable management of MLN is achievable through genetic improvement and replacement of old susceptible varieties with farmer-preferred varieties that combine MLN resistance with tolerance to other prevailing biotic and abiotic stresses. To effectively breed for MLN resistance, it is important to identify sources of resistance, determine the genetic nature of resistance and employ efficient breeding techniques that will result in high genetic gains from selection. This study aimed to dissect the genetic nature of MLN using elite and introduced inbred lines from tropical and temperate maize genetic pools, new biparental populations and potential hybrids. The genetic analysis was conducted in five studies representing the major stages of maize breeding, from pre-breeding to variety development. In the pre-breeding study, the breeding potential for MLN resistance among 18 tropical and temperate inbred and doubled haploid (DH) lines was conducted to identify the best parents for population development. The second study on the genetic potential and usefulness of new pedigree populations was conducted using nine segregating biparental populations derived by crossing susceptible elite and recycled DH lines to two introduced MLN resistant lines from the KS23 pool. The third study, using a section of these populations, selected three sizable populations, which were phenotyped, genotyped and used to validate quantitative trait loci (QTL) linked to MLN resistance in the KS23 genetic background. The fourth study, moving towards product development, entailed determining the potential of new lines and single crosses for use as MLN resistant testers and hybrid parents. In this study, the combining ability for MLN resistance and agronomic traits was estimated among tropical MLN resistant maize lines and prospective single cross testers. Finally, MLN-resistant three-way test cross hybrids (potential new varieties) were evaluated to determine the magnitude of genotype by environment interaction (GEI) and yield stability of hybrids under stress and optimum conditions. Results indicated overall high genetic variation for MLN resistance among introduced and adapted inbred lines, segregating populations and test cross hybrids. High heritability estimates were also observed among the diverse germplasm categories. With the high heritability estimates observed, significant gains from selection can be achieved for both MLN resistance and agronomic traits. The pre-breeding assessment identified good inbred lines suitable for formation of new MLN resistant populations. Testcross analysis led to identification of two resistant inbred lines and seven potential single cross testers that could be used for routine MLN resistance breeding. Multi-location experiments on three-way testcross hybrids identified 11 potential hybrids stable under MLN pressure and disease-free conditions. These hybrids could be further tested, released and commercialised. Genetic analysis and QTL mapping using biparental populations led to the validation of one major recessively inherited QTL located on the long arm of chromosome 6, consistently linked to three Kompetitive allele-specific polymerase chain reaction (KASP) markers across three mapping populations. This major candidate QTL needs to be fine-mapped and high-quality markers linked to the QTL selected and used for routine MLN resistance breeding in SSA and globally
Biological control pre-release studies on the ecological impacts and biotic interactions of Robinia pseudoacacia L. (Black locust) with indegenous fauna and flora in South Africa
No full textThe growing invasion of Afromontane grassland ecosystems of South Africa by Robinia pseudoacacia, a tree from North America is threatening this fragile and fast disappearing biome. Despite numerous studies on the species in the northern hemisphere, a serious lack of information in the southern hemisphere was noted. With the species targeted for biological control in South Africa, there is a need to understand its impacts in a local context and set baseline indicators for future evaluation of management interventions. Thus, multi-scaled studies to determine and quantify the impacts of this IAP were undertaken in the eastern Free State Province of South Africa. These included interactions between the invasive alien tree, biotic and abiotic components of the ecosystem, and implications of control on human wellbeing. Robinia pseudoacacia functional traits such as phenology, canopy cover, tree diameter and population demographics such as population density were measured including how these influence abiotic components of the ecosystem such as temperature and light availability (microclimatic conditions). Furthermore, the cascading effects of environmental modification on native vegetation and grassland arthropods as well as interruption of key ecosystem services such as rangeland condition and pollination in agro-ecological ecosystems were evaluated. Contributions of the invasive alien tree to livelihoods of invaded communities were also assessed inorder to avoid any conflict of interest that may arise from its management.
Results showed that invasion by R. pseudoacacia significantly transforms understory microclimatic conditions. Temperatures were at least 2ºC lower under R. pseudoacacia stands as compared to uninvaded grassland while light availability differed by at least 1200 lumens-ft2. Grass communities subsequently differed by 96% between invaded plots and adjacent uninvaded grassland. Species richness was significantly lower in the understory where there was a dominance of exotic grasses . Furthermore, these habitat conditions differentially affect grassland arthropod assemblages, with grasshoppers in the family Acrididae, the most common grassland taxa to be excluded from invaded sites. Apart from the absence of thier main host plants, invasion mediated differences in microenvironments appeared to be the main driver of this shift in arthropod assemblages.
This study also provided evidence that important ecosystem services such as grazing and pollination, are affected by R.pseudoacacia invasion. Apart from the reduction in available rangeland, changes in grass communities also significantly lowers the grazing capacity of rangelands. Differences in grass species composition between invaded and uninvaded rangeland resulted in a reduction in range condition especially under smaller and dense R. pseudoacacia stands. Furthermore, results from paired flower visitation rates in an agro-ecological system showed that R. pseudoacacia shares pollinators with apples. Since the two plants develop flowers during the same period, there is competition for key pollinators such as Apis mellifera. Hence, successful pillonation of apples is compromised with a potential reduction in fruit yield and quality.
A survey conducted in this study showed that while the tree is currently being utilised by peri-urban dwellers, it is not the preferred species for several functions. Several respondents cited harvesting difficulties (due to thorns) and poor firewood qualities (production of bad smoke) as the major reasons for the underutilisation of R. pseudoacacia. Moreover, its contribution to household incomes is very insignificant while several negative impacts such as reduction in building space and uncontrollable spreading were noted.
Information generated from this study shows that R. pseudoacacia is negatively affecting grassland ecosystems and subsequent ecosystem services. Therefore, there is a need to find a sustainable management solution for the species. Considering the limited success achieved by current management efforts, biological control is expected to be the major technique implemented for the species. Several impacts quantified in this study can be used to prioritise the species for management as well as a baseline for evaluation of future management interventions.Department of Forestry, Fisheries and Environment through the Centre for Biological Control, Rhodes University – University of the Free State research partnership