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Exploring the prevalence and molecular basis of tomato leaf mould caused by Fulvia fulva on disease-resistant tomato cultivars in commercial New Zealand glasshouses : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Plant Breeding at Massey University, Palmerston North, New Zealand
(Massey University, 2026) Ferrada-Hartley, Francisco
Leaf mould disease, caused by the fungus Fulvia fulva (formerly Cladosporium fulvum), can significantly reduce tomato yields in commercial glasshouses. Protection against this disease has predominantly been based on the introgression of one or two Cf resistance genes from wild tomato species. For example, most resistant cultivars contain the Cf-9 locus, which harbours the resistance genes Cf-9B and Cf-9C. In all cases, these Cf genes encode immune receptors that recognise specific virulence factors of F. fulva called effectors. Unfortunately, however, resistance conferred by Cf genes can be overcome through mutation or deletion of the genes encoding the recognised effectors. This has led to the global emergence of F. fulva strains capable of overcoming all deployed Cf genes. As such, currently deployed Cf genes no longer provide reliable control against leaf mould disease. Recently, wild tomato plants with one or more of 10 new Cf resistance genes were identified, suggesting that these genes could be stacked in commercial tomato cultivars through breeding to provide durable resistance. However, before these Cf genes can be introduced into commercial tomato cultivars, it must first be determined whether they have already been overcome by F. fulva through mutation of the corresponding effector genes. In the current study, I aimed to address this knowledge gap by investigating F. fulva strains present in commercial tomato glasshouses across New Zealand. Specifically, this project sought to determine the prevalence of leaf mould on various cultivars currently grown in the country, particularly those carrying Cf-derived resistance genes (including cultivars marketed as “Ff:A–E”, which harbour the Cf-9 locus). Initial glasshouse observations revealed apparent leaf mould symptoms on cultivars previously considered to be resistant. Establishing whether these cultivars remain protected, or whether their resistance genes have been widely overcome, is essential for informing future breeding programmes. To address this aim, a field survey was conducted across 20 tomato growing sites in New Zealand, encompassing mostly commercial glasshouses, during which leaf mould-infected samples were collected, for the most part, from tomato cultivars considered to be resistant. Leaf mould was recorded on all four resistant cultivars sampled, indicating that these cultivars did not remain reliably protected under the conditions encountered, though confirming this pattern nationally would require wider scrutiny across more cultivars and locations. F. fulva was isolated from three samples (one from a resistant cultivar and two from F. fulva collections), visually characterised, stored, and prepared for genomic DNA extraction. The three isolates spanning a temporal range (collected in the 1980s, 2022 and 2025) were whole-genome sequenced, and the coding sequences of 20 known avirulence (Avr) and extracellular protein (Ecp) effector genes were reconstructed and compared against published reference alleles to identify mutations, truncations and gene-loss events. The effector repertoire was largely conserved, with changes concentrated in the Avr genes: a mutation profile consistent with the predicted evasion of several deployed Cf genes. In contrast, the effectors recognised by the recently identified resistances were largely intact across all isolates, indicating that these new Cf genes are predicted to remain effective and represent viable candidates for deployment. Together, these findings provide a first genomic assessment of the current status of leaf mould resistance in commercially grown tomato cultivars in New Zealand. By clarifying which Cf resistance genes appear to have been overcome and which are predicted to remain effective, this research supports evidence-based cultivar deployment, reduces the risk of resistance breakdown, and strengthens Integrated Pest Management (IPM) strategies within the New Zealand tomato industry.
Exploring young people’s understandings of relationships and sexuality education (RSE) in Aotearoa New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Master of Arts in Psychology at Massey University, Aotearoa (New Zealand)
(Massey University, 2026) Brogan, Melody Shea Collecutt
Relationships and Sexuality Education (RSE) plays an important role in supporting young people’s sexual and emotional wellbeing by developing their knowledge and skills to navigate relationships, sexuality, and identity. However, concerns remain about whether current approaches adequately reflect young people’s lived experiences and the complexities of contemporary sexual lives. In Aotearoa New Zealand, RSE has traditionally prioritised biological understandings of sexuality and risk prevention, with less emphasis on emotional, relational, and identity-based aspects of wellbeing. I explored young people’s understandings of school-based RSE in Aotearoa New Zealand and its relevance to their sexual and emotional wellbeing. Drawing on a contextualist epistemological framework, an anonymous online qualitative survey was conducted with 32 tertiary students aged 18 years and older who had completed school-based RSE within the previous five years. Data were analysed using Braun and Clarke’s (2006) reflexive thematic analysis. Four themes were developed: (1) RSE had limited usefulness and was incomplete; (2) RSE experienced as not inclusive; (3) how RSE was delivered shaped student engagement; and (4) informal sources became a substitute for RSE. Participants described RSE as largely focused on biology, sexual health risks, and pregnancy prevention, while emotional intimacy, communication, pleasure, diverse identities, and real-world relationship experiences were often absent or insufficiently addressed. When formal education did not meet their needs, participants actively sought knowledge through peers, online resources, and personal experience. The findings highlight a disconnect between the RSE participants received and the knowledge and skills they considered necessary to navigate contemporary sexual and relational experiences. By centring young people’s voices, the findings demonstrate the need for RSE that is more inclusive, relational, and responsive to young people’s realities, moving beyond predominantly biological and risk-based approaches to better support lifelong sexual and emotional wellbeing.
Phenotypic variation is greater in the absence of gene flow in three alpine grasshoppers
(The Royal Society, 2026-04-02) Meza-Joya FL; Morgan-Richards M; Trewick S
Alpine organisms distributed on mountain ranges with broad latitudinal and elevational gradients provide an appropriate setting to explore clinal phenotypic variation and the role of gene flow. We used Bayesian generalized linear mixed models to investigate body size variation along genetically connected (elevation) and disrupted (latitude) gradients in three flightless alpine grasshopper species endemic to the Southern Alps (Kā Tiritiri o Te Moana) of New Zealand (Aotearoa), and test whether variation relates to geographic differences in environmental conditions. We found latitudinal size clines in all species, but little phenotypic variation was explained by elevation. Size clines are consistent with theoretical expectations of local adaptation, with minor roles for plasticity and drift. Size variation in each species has distinct climatic association, potentially reflecting microhabitat selective pressures and distinct evolutionary histories. Latitudinal size clines suggest that phenotypic differences may result from barriers to gene flow among mountaintop populations, while gene flow on steep elevational clines homogenizes body size. Rapid environmental change imposes selection that could result in local adaptation, but we have shown here that selection pressure cannot be considered in isolation from gene flow when predicting how populations will respond to climate change.
Achieving English proficiency : a qualitative study of Chinese students’ language learning strategies while studying in Aotearoa New Zealand : a research report in partial fulfilment of the requirements for the degree of Master of Business Studies, School of Humanities, Media, and Creative Communication, Massey University, New Zealand
(Massey University, 2026) You, Sylvia
Chinese students invest considerable effort in English learning to achieve the required English test scores to enroll in New Zealand universities. However, many of them still struggle to use English effectively in real-life communication. These challenges include language, academic study, social integration and emotional factors. The reasons for students’ uneven English skills are complex and involve cultural, contextual, and affective influences. Existing studies have not sufficiently explored how students select and interact with language-learning strategies in real communication contexts, from both students' and teachers’ perspectives. This study employs a qualitative approach to explore the effective language-learning strategies that Chinese students use to address various challenges in real-life contexts. It examines students’ perceptions of English proficiency, the challenges they encounter, and the strategies they take and the reasons for those actions. Teachers’ perspectives are also included to identify any issues that may be overlooked by students and to provide professional interpretation of the challenges. The analysis is informed by Oxford’s S2R model to interpret how students address these challenges in their lives. Findings show that cognitive strategies are mainly used to deal with language and academic tasks, social interaction is valuable for improving English proficiency through communication with people in the host environment, and affective strategies are used throughout the process to reduce stress and maintain motivation. Overall, effective language learning requires learners to be flexible, select and combine cognitive, social interaction, and affective strategies to meet individual needs and learning context.
Mātauranga māori of the mouth and teeth among Tairāwhiti Māori : thesis presented in partial fulfilment of the requirements the degree of Master of Health Science at Massey University, Palmerston North, New Zealand
(Massey University, 2025) Reihana, Wiremu
Ko te waha te kuaha ki te ao — the mouth is the doorway to the world. Māori understand the waha (mouth) as a taonga carrying whakapapa, mana, and identity. Colonisation disrupted these relationships, reducing the waha to a biomedical object and contributing to persistent oral-health inequities among Māori, particularly in Te Tairāwhiti. Tamariki experience some of the highest rates of preventable decay, and whānau often inherit the normalisation of toothlessness as inevitable (Haag et al., 2021; Ministry of Health, 2024). This thesis addresses that problem by reframing oral health within a kaupapa Māori worldview. Using a mixed approach—literature review grounded in mātauranga Māori and thematic analysis of interviews with kaumātua, practitioners, and whānau—the study explores the cultural, spiritual, and ecological dimensions of the waha. Data were analysed through reflexive thematic coding aligned with whakapapa and tikanga principles (Smith, 2012; Pihama, 2010). Findings reveal that the waha remains a vessel of identity, ceremony, and relational authority. Despite colonial disruption, mātauranga Māori persists in everyday practices such as karakia, waiata, and rongoā, and is being revitalised through whānau-led initiatives (Royal, 2003; Kāretu, 1993). Reclaiming the waha emerges as both a health strategy and a decolonising act—restoring cultural confidence, strengthening whānau authority, and challenging systemic inequities (Reid et al., 2014; Stuart et al., 2011). The thesis contributes to academic scholarship by advancing a kaupapa Māori framework of oral health that integrates cosmology, ecology, and relational ethics. For community practice, it offers practical recommendations for whānau-centred models, Kaupapa Māori-led service design, and policy reforms that embed tikanga, reo, and mātauranga Māori (Durie, 1994; Robson et al., 2011). Ultimately, it calls for an Aotearoa where Māori oral health is not defined by loss, but by sovereignty, resilience, and mauri ora.