Browsing by Author "Roskruge N"

Now showing 1 - 4 of 4
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    Co-production of insights for place-based approaches to revitalise te taiao in Aotearoa New Zealand
    (John Wiley and Sons Australia, Ltd on behalf of New Zealand Geographical Society, 2024-11-16) Turner JA; Stokes S; Jones RTH; Hemi M; Collins H; Vannier C; Burkitt L; Bradley C; Doehring K; Macintosh KA; Young J; Roskruge N; Perry-Smith P; Iosefa RK; Walker N; Young F; Bell A; McDermott A; Wood C
    Communities across Aotearoa New Zealand are collaborating to reverse ecological decline, but little attention has been given to understanding the deeper relationship required with our physical and socio-cultural landscapes. We used knowledge co-production to develop 11 insights to support place-based strategies that nurture a collective responsibility to revitalise both people and place. Twenty-five subject matter experts across communities, government, industry and research drew from their collective expertise and the review of 63 local-to-global case study examples of farm-to-community-scale place-based approaches. A key output from this work is an Aotearoa New Zealand framework that diagrammatically represents the interdisciplinary nature of the 11 insights.
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    Effects of Abiotic Stress Associated with Climate Change on Potato Yield and Tuber Quality Under a Multi-environment Trial in New Zealand
    (Springer Nature, 2024-03-06) Siano AB; Roskruge N; Kerckhoffs H; Sofkova-Bobcheva S
    In the 2018/19 growing season, a multi-environment trial in Opiki, Hastings, and Ohakune located in three different regions of the North Island of New Zealand was conducted to evaluate responses of selected potato cultivars to abiotic stress associated with climate change. Heat and drought stresses were evident with supra-optimal temperatures (> 25 °C) in Opiki and Hastings and sub-optimal rainfall (< 500 mm) in Opiki, which influenced the different morpho-physiological characteristics of the potato crop, ultimately affecting yield and tuber quality. These abiotic stresses also increased the incidence of malformation, growth cracks, and second growth in tubers reducing the total and marketable tuber yields by 43% and 45%, respectively. In addition, the genotype × environment analysis showed that Ohakune had the most favourable environmental conditions for potato production since all cultivars in this site had superior marketable tuber yields. ‘Taurus’ was the most stable and adaptable cultivar across trial sites (wide adaptation), whilst ‘Hermes’ and ‘Snowden’ were more adapted under Opiki and Hastings conditions (specific adaptation), respectively. As established in this study, heat and drought stresses have significant effects on the morpho-physiology, yield, and tuber quality of commercial potato cultivars in New Zealand.
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    Nitrous Oxide Treatment after Pollination Induces Ploidy Changes in Statice (Limonium sp.)
    (MDPI (Basel, Switzerland), 2024-08-01) Cordoba-Sanchez J; Funnell K; Hedderley D; Roskruge N; Morgan E; Neri D
    The production of statice (Limonium sp.) plants with higher ploidy through induction of whole-genome duplication (WGD) via the spindle disrupter nitrous oxide (N2O) was examined as a strategy to increase the germplasm diversity of the species. Furthermore, the impact of the resulting ploidy changes on the morphological features of the progeny was examined. Intraspecific crosses between diploid plants of Limonium sinuatum (L.) Mill and L. perezii (Stapf) Hubb. were conducted daily for seven consecutive days, with subsequent exposure to N2O. Within the resulting progeny, between 16% and 35% of plants were polyploid when N2O was applied between one and four days after pollination. A comparative analysis between diploid and tetraploid progeny was conducted, using a selection of 10 L. sinuatum (5 diploids and 5 tetraploids) and 7 L. perezii (4 diploids and 3 tetraploids) genotypes. The results revealed differences between tetraploids and their diploid counterparts for most of the evaluated characteristics. Tetraploid plants of L. sinuatum and L. perezii exhibited pollen grains 1.5 times larger in plan area; the leaves and main floral stem diameter were 1.2 and 1.5 times thicker for L. sinuatum and L. perezii, respectively, the guard cell length was 1.4 times greater for both species, while the stomatal density was 0.6 times lower for L. perezii and 0.8 for L. sinuatum. The leaf area and main floral stem wings were affected by the ploidy increase only for L. sinuatum. In this regard, tetraploid plants of L. sinuatum displayed leaves 1.8 times bigger and main floral steam wings 2.4 times wider in comparison to diploid plants. In conclusion, the production of tetraploid Limonium plants using N2O shortly after pollination creates new diversity for breeding. These findings underscore the potential for leveraging polyploidy as a strategy to enhance desirable traits in Limonium species.
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    Yield and tuber quality variability in commercial potato cultivars under abiotic stress in New Zealand.
    (2018) Siano A; Kerckhoffs LHJ; Roskruge N; Sofkova-Bobcheva S