New Zealand Journal of Forestry Science最新文献

{"title":"Climate influence seed production in managed and unmanaged Nothofagus pumilio forests of Southern Patagonia","authors":"Julián Rodríguez-Souilla, J. M. Cellini, F. Roig, María Vanessa Lencinas, J. Chaves, P. L. Peri, G. M. Martínez Pastur","doi":"10.33494/nzjfs542024x295x","DOIUrl":"https://doi.org/10.33494/nzjfs542024x295x","url":null,"abstract":"Background: Annual seed production is key to understand natural forest dynamics and to apply sustainable forest management. This process is subjected to variations according to annual and seasonal climatic conditions, locally affected by El Niño-Southern Oscillation (ENSO) and the Southern Annular Mode (SAM) seasonality. Recognising how these variables affect the dynamics of harvested forests is useful for developing forest management strategies. Therefore, the objective of this study was to analyse annual seed production (SP) in Nothofagus pumilio (Poepp. & Endl.) Krasser stands harvested under variable retention and unmanaged primary forests in Tierra del Fuego, Argentina, related to the occurrence of climatic events over a 17-year period (2006-2022).\u0000Methods: Seed production (million ha-1 year-1) was annually measured in three managed stands with different retention levels (AR: aggregates; DRI: dispersed with aggregate protection; DR: dispersed without aggregate protection) and three primary forests (PF) stands as control sites (4 treatments x 3 areas x 6 replicates x 17 years). Values of occurrences of climatic events (positive or negative values of ENSO and SAM) were related to monthly temperature and rainfall. ANOVAs, correlation analyses and statistical modelling were performed to predict SP based on climatic variables and forest treatments.\u0000Results: Seed production varied over years and among forest treatments depending on annual climate variations, with annual averages for the studied period of: 9.35 million ha-1 year-1 for PF, 7.16 million ha-1 year-1 for AR, 2.25 million ha-1 year-1 for DRI and 1.08 million ha-1 year-1 for DR. ENSO+ and SAM+ acted as a trigger of high SP, associated to higher temperatures and dry conditions, mainly during spring and summer. The models predicted SP explaining 73-85% of its variability, considering minimum and maximum temperatures and ENSO mean values as better predictors.\u0000Conclusions: Findings presented in this study have important implications for forest management as a tool for understanding forest dynamics related to seeding, a key factor for forest regeneration in a context of high climate variability. However, within a context of climate change with extreme events, there is a need for long-term monitoring of seeding processes in Nothofagus forests.\u0000 ","PeriodicalId":19172,"journal":{"name":"New Zealand Journal of Forestry Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141806388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing the impacts of experimental mid-rotation forest fertiliser treatments on water quality","authors":"B. Baillie, J. Elleouet, Graham W. R. Coker","doi":"10.33494/nzjfs542024x356x","DOIUrl":"https://doi.org/10.33494/nzjfs542024x356x","url":null,"abstract":"Background: Planted forests face on-going challenges to increase productivity while remaining within sustainable limits. Forest management activities that potentially impact on water quality are under increasing public scrutiny and regulatory controls. New Zealand’s forest industry is experimenting with aerially applied, mid-rotation fertiliser treatments as a sustainable option to increase productivity from planted forests. However, the effect of such applications on water quality requires investigation.\u0000Methods: Field trials were established to assess the effects of two conventional fertiliser applications (either granular di-ammonium phosphate (DAP) or granular urea) and a new-to-forestry liquid foliar fertiliser blend, on nitrogen and phosphorus concentrations in stream water of three planted forest sites representing a range of New Zealand climatic and soil environments.\u0000Results: Overall, the liquid foliar fertiliser treatment had the least impact on water quality compared with the two conventional fertiliser treatments. On the day of fertiliser application, when compared with pre-treatment in-stream concentrations, the urea treatments resulted in short-term increases in total nitrogen. The DAP treatment increased total phosphorus and dissolved reactive phosphorus concentrations with peak concentrations declining within hours. In the post-application period, any increases in nutrient concentrations in stream water were mainly associated with rainfall events within six months of application and at one site, the resumption of stream flow following a dry spell. Riparian ‘no-spray’ buffers of varying widths assisted in mediating the impacts of fertiliser applications.\u0000Conclusions: Initial evidence from these trials indicates that mid-rotation fertiliser treatments have the potential to provide an alternate management option to increase forest productivity or disease resilience with minimal or only short-term effects to water quality. However, further research on their environmental effects would support the development of guidelines specific to mid-rotation fertiliser applications, particularly if mid-rotation fertiliser applications become standard management practice in the forest industry.","PeriodicalId":19172,"journal":{"name":"New Zealand Journal of Forestry Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141818225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mid-term results and prospects for irregular shelterwood systems in hardwood-dominated temperate rainforests in Chile","authors":"Pablo J. Donoso, Tomás Riquelme-Buitano, Daniel P. Soto","doi":"10.33494/nzjfs542024x323x","DOIUrl":"https://doi.org/10.33494/nzjfs542024x323x","url":null,"abstract":"Background: When possible, silviculture should aim to develop mixed-species multi-aged forests that can be more productive and resilient to disturbances, provide high-quality timber and sustain greater amounts of biomass. Southern Chile is covered by temperate rainforests dominated by a mixture of tree species, such as the Evergreen forest type (EFT). The irregular shelterwood regeneration method is a novel approach aimed at developing irregular multi-aged forests following the retention of the residual forest (no final cut). Here, we report mid-term results after implementing these cuttings in two EFT forests in the Coastal Range and discuss its prospects for other temperate rainforests.\u0000Methods: Two forests were sampled and evaluated in terms of composition, structure and growth, focusing on the new cohorts developed or released after the irregular shelterwood cuts. One forest was cut in a low-productivity site at 600 m (Hueicolla) in 1983, and the other in a medium-productivity site at 350 m (Llancahue) in 2009. In Hueicolla, 63% of the basal area was harvested from an old-growth forest where the main residual tree species were Eucryphia cordifolia, Laureliopsis philippiana and Saxegothaea conspicua. In Llancahue, 40% of the total basal area was harvested in a mature secondary forest dominated by Nothofagus dombeyi.\u0000Results: The understorey developed in Hueicolla had 3,600 trees per ha and a quadratic stand diameter of 15 cm. It was dominated by the mid-tolerant species Eucryphia cordifolia, Gevuina avellana and Lomatia ferruginea, plus the shade-tolerant Amomyrtus luma. In Llancahue, a dense lower canopy was dominated by Podocarpus salignus and Drimys winteri, both mid-tolerant species, which included 81,000 seedlings and saplings < 5 cm per hectare and 560 ingrowth 5-10 cm trees per hectare.\u0000Conclusions: The irregular shelterwood cuts allowed the development of dense understorey tree layers below the residual trees. However, the tree composition of the new cohorts largely differed from that of the residual trees and was dominated by mid-tolerant species, including some short-lived species. The irregular shelterwood method proves appropriate for the EFT and may likely be successful in other forest types with valuable mid-tolerant species.","PeriodicalId":19172,"journal":{"name":"New Zealand Journal of Forestry Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-04-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140683713","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Use of nitrogen-fixing plants to improve planted forest soil fertility and productivity in New Zealand: A review","authors":"Nicola M. Reid, Kathryn Wigley, Aysha Nusrath, S. Smaill, L. Garrett","doi":"10.33494/nzjfs542024x329x","DOIUrl":"https://doi.org/10.33494/nzjfs542024x329x","url":null,"abstract":"Background: Planted forests with low fertility soils are likely to require increased inputs of nitrogen (N) to satisfy increasing productivity demands. The use of N fertilisers will become more challenging due to their increasing cost and the risk of unwanted environmental impacts. Nitrogen-fixing plants may provide an alternative option to chemical fertilisers that is not only cheaper but has a lower greenhouse gas footprint.\u0000Methods: Information on N-fixing plants was collated from available literature, focusing on species previously associated with planted forests as well as other exotic N-fixing trees and New Zealand native plants not used in commercial planted forests.\u0000Results: Benefits to planted forest growth in New Zealand by N-fixing plants have been proven in only a few cases. Lupinus arboreus Sims was used in the 1970s and 1980s to increase N inputs in a planted Pinus radiata D.Don coastal forest, and improved P. radiata productivity was demonstrated. Productivity gains ceased when a blight disease infected the lupin population. Many N-fixing plants have been shown to tolerate low fertility soils and establish in planted forests, but there is limited information on their N contribution to the soil, and whether this N contribution increases P. radiata productivity. Such N-fixing plants include Lotus species, clover (Trifolium species) and weeds such as gorse (Ulex europaeus L.) and broom (Cytisus scoparius (L.) Link), which are commonly found in association with P. radiata forests. New Zealand native N-fixing shrubs may be suitable but there is limited information available describing N-fixation or forestry management for native plant species.\u0000Conclusions: Nitrogen-fixing plants are a valuable resource, which when managed properly could be used for enhancing productivity. Issues with pests and disease, and limited knowledge regarding the management of N-fixing species, restricts adoption in planted forests. Well-designed research is needed to assess impacts on whole forest system N cycling as well as selection of appropriate plant species for use in planted forests without unintended consequences such as competition for soil moisture or light. This research needs to be integrated with forest management and delivered as practical options to ensure success.","PeriodicalId":19172,"journal":{"name":"New Zealand Journal of Forestry Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140688782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diversity and growth patterns of woody species in the Mediterranean Coastal range of Chile: A case study in Altos de Cantillana","authors":"Stephanie Gibson-Carpintero, Anahí Ocampo‐Melgar, Alejandro Venegas González","doi":"10.33494/nzjfs542024x318x","DOIUrl":"https://doi.org/10.33494/nzjfs542024x318x","url":null,"abstract":"Background: The Altos de Cantillana mountain range (ACMR) in central Chile is composed of different vegetation communities, and is currently a priority site for conservation, due to its high endemism, high anthropogenic pressure and vulnerability to climate change. Research on biodiversity and carbon stocks in ACMR is essential to comprehend the resilience of these forests and to define conservation strategies. This study examines the spatial variability of biodiversity and tree biomass patterns along the entire altitudinal gradient of the ACMR.\u0000Methods: Six tree species communities were studied in Altos de Cantillana Nature Sanctuary, along an altitudinal gradient ranging from 415 to 2010 m. Woody species regeneration and inventory plots, as well as dendrochronological sampling in ~150 trees were carried out. Diversity patterns were analyzed using the Jaccard index and alpha index. Growth patterns of dominant trees species were analyzed by ring-width and trunk biomass chronologies, focusing on the recent megadrought period since 2010.\u0000Results: The forest inventory revealed a notable decline in alfa diversity patterns with increasing elevation. The moist sclerophyllous forest exhibited the highest diversity. However, we did not find a pattern between elevation and diversity (and abundance) at the seed regeneration inventory level. Additionally, we identified three clusters of woody species similarity: (i) sclerophyllous, shrubs and hygrophilous forest (<1,000 m.a.s.l.); (ii) high-elevation sclerophyllous forest (>1,500 m.a.s.l); and (iii) deciduous forests (~ 2,000 m.a.s.l). Furthermore, declining growth rates were observed in all communities studied beginning in the 1980s, with even a stronger reduction in radial growth (35% on average) and biomass accumulation (56% on average) when comparing the megadrought with six decades earlier.\u0000Conclusions: We concluded that there is a negative correlation between woody species diversity and elevation. However, there are no altitudinal patterns in seedling regeneration diversity and abundance, which puts the natural succession in ACMR at risk. Additionally, we have determined that the accumulation of trunk biomass in dominant woody species has been significantly impacted by the recent megadrought period. This has affected the sink capacity of forest communities in ACMR. Therefore, our findings can significantly contribute to more efficient and timely decision-making processes regarding the conservation and restoration of this globally unique ecosystem.","PeriodicalId":19172,"journal":{"name":"New Zealand Journal of Forestry Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140766425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seed thermo-priming accelerates the growth of Ceiba glaziovii (Kutze) K.Schum. seedlings","authors":"José Laurindo dos Santos Júnior, Elizamar Ciríaco da Silva","doi":"10.33494/nzjfs542024x264x","DOIUrl":"https://doi.org/10.33494/nzjfs542024x264x","url":null,"abstract":"Background: Global climate changes have caused temperature increases that can harm plant development, especially the initial growth and establishment of seedlings for the recovery of degraded areas. However, there are species in which these losses are attenuated when the seeds are thermo-primed to sublethal temperatures. Therefore, the objective of the present study was to evaluate the influence of seed heat conditioning on germination and initial growth of Ceiba glaziovii (Kuntze) K. Schum seedlings, an endemic species occurring in seasonally tropical dry forest in Brazil.\u0000Methods: Seeds of C. glaziovii were exposed to 70 oC for 15, 30, 45, 60 and 90 minutes as pre-germination treatments. The control did not undergo heat treatment. Germination variables, vegetative growth, survival rate and normal leaves were evaluated.\u0000Results: Thermo-priming negatively affected the germination proportion of C. glaziovii seeds with increasing exposure time. However, it significantly enhanced vegetative growth and seedling survival rate of this species after transplanting, without impairing the formation of normal leaves.\u0000Conclusions: Thermo-priming of seeds was found to produce more vigorous seedlings of Ceiba glaziovii.","PeriodicalId":19172,"journal":{"name":"New Zealand Journal of Forestry Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140397588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relationship between photosynthetic-water and nitrogen use efficiencies in young Pinus taeda L. trees at two contrasting sites","authors":"Marco A. Yáñez, S. Espinoza, J. Ovalle, C. Magni, Eduardo E. Martínez","doi":"10.33494/nzjfs542024x281x","DOIUrl":"https://doi.org/10.33494/nzjfs542024x281x","url":null,"abstract":"Background: Nitrogen and water are important limiting factors to forest productivity. At the plant level, there is contrasting empirical evidence about the trade-off between water use efficiency (WUE) and nitrogen use efficiency (NUE).\u0000Methods: A study was conducted on 3-year-old loblolly pine (Pinus taeda L.) trees sampled at two contrasting sites (Virginia Piedmont (VA) and North Carolina Coastal Plain (NC)) in the southeastern United States. We investigated the leaf-level relationship between water and nitrogen use efficiency (i.e., WUEins versus PNUE). Both parameters were measured in the fall, three years after outplanting.\u0000Results: WUEins and PNUE were higher at VA than NC. At both sites, WUEins increased from August to November, while PNUE showed a consistent decline for the same period only at NC, with no clear pattern observed at VA. The Pearson’s coefficient of correlation (r) between WUEins and PNUE was negative (r=0.50) at VA in August, positive (r=0.77) at NC in October, and insignificant for the other measurement dates.\u0000Conclusions: Regardless of the site, at the young stage of stand development, WUEins and PNUE were mostly uncoupled, although it can be speculated that a transient trade-off between these two variables can be expected depending on soil water rather than nitrogen availability.","PeriodicalId":19172,"journal":{"name":"New Zealand Journal of Forestry Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140398155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Peeler core and slabwood fibre properties for Pinus radiata D.Don pulp production","authors":"J. Elissetche, L. Apiolaza, R. Alzamora, Luis O. Soto, Jean Pierre Lasserre","doi":"10.33494/nzjfs542024x268x","DOIUrl":"https://doi.org/10.33494/nzjfs542024x268x","url":null,"abstract":"Background: Pulp production based on Pinus radiata D.Don is constantly improving the value recovery of logs. One example is using the peeler cores and slabwood derived from sawing and peeling processes to produce pulp. However, these two raw materials have not been characterised for their fibre properties. \u0000Methods: We report on four wood fibre quality attributes derived from peeler cores and slabwood, directly influencing pulp quality and pulping process: fibre length (mm), fibre width (µm), fines content (%), and coarseness (µg/m). This pilot study sampled two P. radiata stands grown on different sites and early silvicultural regimes in the Araucanía Region of Chile. Analysis of wood fibre consisted of three trees per stand, and six discs per tree: two at the bottom, two at breast height (1.3 m), and the last two at 5.23 m height. \u0000Results: The trajectory of mean annual increment in diameter at breast height (MAI) and periodic annual increment in diameter at breast height (PAI) for trees in the two stands aligned with their respective site qualities and silvicultural regimes. In Stand 1, with a site index of 36, and Stand 2, with a site index of 31, the average proportions of juvenile wood (measured at 1.3 m) were 50% and 53%, respectively. Thus, despite weed control and fertiliser application in Stand 1, there was no increase observed in the proportion of juvenile wood. There were significant differences in fibre properties between peeler core and slabwood, and these differences were present across the range of tree heights and diameters (p<0.05). While there were no statistically significant differences among disc positions, significant distinctions emerged between stands and wood types. The interaction between these factors was also found to be statistically significant (p<0.05).\u0000Conclusions: Our study suggests that adding these two materials into the mix for producing pulp would have positive implications due to pulp from peeler core is more suitable for printing and writing grades and addition of mature wood from slabwood, could improve strength properties of paper manufacture. However, it is necessary to test the optimal proportion for the final mix.","PeriodicalId":19172,"journal":{"name":"New Zealand Journal of Forestry Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140456554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Do leaf traits affect insect herbivory in a Chinese cork oak forest?","authors":"Xinliang Shao, Ke Cheng, Qin Zhang, Fei Xu, Lili Li","doi":"10.33494/nzjfs542024x294x","DOIUrl":"https://doi.org/10.33494/nzjfs542024x294x","url":null,"abstract":"Background: It is widely accepted that certain leaf traits indicating leaf quality play an important role in regulating insect herbivory. Numerous studies have attempted to find a clear relationship between insect herbivory and leaf traits. However, the results are inconsistent. In particular, it is still unclear whether leaf traits of a tree species affect insect herbivory in the field.\u0000Methods: We examined the effects of leaf traits including structural defensive traits (specific leaf area), nutritional traits (nitrogen content, water content, and soluble sugar content), and chemical defensive traits (tannin content and carbon content) on variation of insect herbivory among three forest strata (vertical variability) and 18 locations (horizontal variability) in a Chinese cork oak (Quercus variabilis) forest landscape.\u0000Results: Vertically, insect herbivory in the low-canopy stratum was significantly higher than in the other strata, but variation of leaf traits among strata had little explanatory power for the vertical pattern of insect herbivory. Horizontally, leaf carbon content had weak negative effects on insect herbivory while leaf tannin content had weak and divergent effects on insect herbivory in different strata.\u0000Conclusions: Leaf traits selected in this study have weak effects on insect herbivory in the Chinese cork oak forests we studied. These effects may be masked by other abiotic and biotic factors, but further examination is needed.","PeriodicalId":19172,"journal":{"name":"New Zealand Journal of Forestry Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140459095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of light intensity and seal type on the in vitro elongation and adventitious rooting of Eucalyptus grandis × E. urophylla","authors":"Denys Matheus Santana Costa Souza, Sérgio Bruno Fernandes, Vinícius Politi Duarte, Letícia Vaz Molinari, Gustavo Leal Teixeira, G. Brondani","doi":"10.33494/nzjfs542024x284x","DOIUrl":"https://doi.org/10.33494/nzjfs542024x284x","url":null,"abstract":"Background: Rejuvenation/reinvigoration of tissues through micropropagation has become an important tool for clonal propagation in eucalypts species. This study evaluated the effect of photomixotrophism (i.e., light intensity and seal type) on in vitro elongation and adventitious rooting to identify the limiting factors on in vitro culture of the Eucalyptus grandis × E. urophylla hybrid.\u0000Methods: Nodal segments (i.e., explants) from ministumps grown in a semi-hydroponic system were collected. The effects of light intensity and seal type on in vitro elongation and adventitious rooting stages were evaluated from a 40 μmol m-2 s-1 fluorescent lamp and 20, 40, and 80 μmol m-2 s-1 red/blue LEDs, with (through porous membranes) and without gas exchange.\u0000Results: Based on the results at 35 d, 40 μmol m-2 s-1 fluorescent lamp and gas exchange combination was the most suitable for in vitro elongation and adventitious rooting of Eucalyptus grandis × E. urophylla. Both factors increased the vigour, shoot length, photosynthetic pigment content, xylem, phloem, stomatal number and density, root length, diameter, number of roots per explant, and adventitious rooting fraction.\u0000Conclusions: Light intensity and seal type influences the in vitro elongation and adventitious rooting of Eucalyptus grandis × E. urophylla. The results contribute to optimising the cloning of commercial eucalypts species by the micropropagation technique.","PeriodicalId":19172,"journal":{"name":"New Zealand Journal of Forestry Science","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140460382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}