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Hans Lambers - One of the best experts on this subject based on the ideXlab platform.
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traits related to efficient acquisition and use of phosphorus promote diversification in Proteaceae in phosphorus impoverished landscapes
Plant and Soil, 2021Co-Authors: Patrick E. Hayes, Michael D. Cramer, Stephen D. Hopper, Francis J Nge, Patrick M Finnegan, Rafael S Oliveira, Benjamin L Turner, Graham Zemunik, Hongtao Zhong, Hans LambersAbstract:Plant species richness increases with declining soil phosphorus (P) availability, especially for Proteaceae in old infertile landscapes. This difference in richness might be attributed to faster diversification in lineages adapted to P-impoverished soils, i.e. species that possess specialised P-acquisition strategies, and have lower leaf P concentration ([P]) and higher seed [P]. Alternatively, a longer time for species accumulation might contribute to high species richness in low-P environments due to the geological stability of the landscapes in which they evolved. We assessed differences in diversification of Proteaceae in P-impoverished vs. nutrient-rich environments and whether these were linked to adaptations to P-impoverished soils. We explored mature leaf and seed [P] and investigated how these traits changed over the evolutionary history of the family, and within two species-rich genera (Banksia, Hakea). Faster diversification was correlated with lower leaf and higher seed [P] for species-rich genera across the Proteaceae. For Banksia and Hakea, diversification rates peaked at relatively low leaf [P], but not at the lowest leaf [P]. Ancestral state reconstructions indicated that low leaf [P] is a trait that was likely present in the early evolution of the Proteaceae, with recent transitions to higher leaf [P] across several species-poor rainforest genera. Diversification of Proteaceae correlated strongly with P-related traits. In an evolutionary context, functional cluster roots, low leaf [P] and high seed [P] were likely key innovations allowing diversification. Selection for low leaf [P] early in the evolutionary history of Proteaceae pre-adapted ancestors of this family to diversify into oligotrophic environments. We discuss how our findings are likely relevant for understanding diversification dynamics of other plant families that occur in P-impoverished environments.
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Phosphorus toxicity, not deficiency, explains the calcifuge habit of phosphorus-efficient Proteaceae.
Physiologia plantarum, 2021Co-Authors: Caio Guilherme Pereira, Patrick E. Hayes, Peta L Clode, Hans LambersAbstract:The calcifuge habit of plants is commonly explained in terms of high soil pH and its effects on nutrient availability, particularly that of phosphorus (P). However, most Proteaceae that occur on nutrient-impoverished soils in south-western Australia are calcifuge, despite their ability to produce cluster-roots, which effectively mobilise soil P and micronutrients. We hypothesise that the mechanism explaining the calcifuge habit in Proteaceae is their sensitivity to P and calcium (Ca), and that soil-indifferent species are less sensitive to the interaction of these nutrients. In this study, we analysed growth, gas-exchange rate and chlorophyll fluorescence of two soil-indifferent and four calcifuge Hakea and Banksia (Proteaceae) species from south-western Australia, across a range of P and Ca concentrations in hydroponic solution. We observed Ca-enhanced P toxicity in all analysed species, but to different extents depending on distribution type and genus. Increasing P supply enhanced plant growth, leaf biomass and photosynthetic rates of soil-indifferent species in a pattern largely independent of Ca supply. In contrast, positive physiological responses to increasing [P] in calcifuges were either absent or limited to low Ca supply, indicating that calcifuges were far more sensitive to Ca-enhanced P toxicity. In calcifuge Hakeas, we attributed this to higher leaf [P], and in calcifuge Banksias to lower leaf zinc concentration. These differences help explain these species' contrasting sensitivity to Ca-enhanced P toxicity and account for the exclusion of most Proteaceae from calcareous habitats. We surmise that Ca-enhanced P toxicity is a major factor explaining the calcifuge habit of Proteaceae, and, possibly, other P-sensitive plants.
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Ecophysiological Performance of Proteaceae Species From Southern South America Growing on Substrates Derived From Young Volcanic Materials.
Frontiers in plant science, 2021Co-Authors: Mabel Delgado, Susana Valle, Marjorie Reyes-díaz, Patricio J. Barra, Alejandra Zúñiga-feest, S. Ruiz, Ariana Bertin-benavides, M. Pereira, Hans LambersAbstract:Southern South American Proteaceae thrive on young volcanic substrates, which are extremely low in plant-available phosphorus (P). Most Proteaceae exhibit a nutrient-acquisition strategy based on the release of carboxylates from specialized roots, named cluster roots (CR). Some Proteaceae colonize young volcanic substrates which has been related to CR functioning. However, physiological functioning of other Proteaceae on recent volcanic substrates is unknown. We conducted an experiment with seedlings of five Proteaceae (Gevuina avellana, Embothrium coccineum, Lomatia hirsuta, L. ferruginea, and L. dentata) grown in three volcanic materials. Two of them are substrates with very low nutrient concentrations, collected from the most recent deposits of the volcanoes Choshuenco and Calbuco (Chile). The other volcanic material corresponds to a developed soil that exhibits a high nutrient availability. We assessed morphological responses (i.e., height, biomass, and CR formation), seed and leaf macronutrient and micronutrient concentrations and carboxylates exuded by roots. The results show that G. avellana was less affected by nutrient availability of the volcanic substrate, probably because it had a greater nutrient content in its seeds and produced large CR exuding carboxylates that supported their initial growth. Embothrium coccineum exhibited greater total plant height and leaf P concentration than Lomatia species. In general, in all species leaf macronutrient concentrations were reduced on nutrient-poor volcanic substrates, while leaf micronutrient concentrations were highly variable depending on species and volcanic material. We conclude that Proteaceae from temperate rainforests differ in their capacity to grow and acquire nutrients from young and nutrient-poor volcanic substrates. The greater seed nutrient content, low nutrient requirements (only for G. avellana) and ability to mobilize nutrients help explain why G. avellana and E. coccineum are better colonizers of recent volcanic substrates than Lomatia species.
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trait convergence in photosynthetic nutrient use efficiency along a 2 million year dune chronosequence in a global biodiversity hotspot
Journal of Ecology, 2019Co-Authors: Caio Guilherme Pereira, Patrick E. Hayes, Odhran S Osullivan, Lasantha K Weerasinghe, Peta L Clode, Owen K Atkin, Hans LambersAbstract:The Jurien Bay dune chronosequence in south‐western Australia’s biodiversity hotspot comprises sites differing in nutrient availability, with phosphorus (P) availability declining strongly with increasing soil age. We have explored the exceptionally high photosynthetic P‐use efficiency (PPUE) of Proteaceae in this region, triggering the question what the PPUE of co‐occurring species in other families might be along the Jurien Bay chronosequence. We explored how traits associated with PPUE, photosynthetic nitrogen (N)‐use efficiency (PNUE) and leaf respiration might converge along the chronosequence, and whether Proteaceae and non‐Proteaceae species differ in leaf traits associated with nutrient use. Seven to 10 species were sampled at three sites differing in nutrient availability (ranging from N‐ to P‐limited). Measurements of leaf light‐saturated photosynthesis and dark respiration were integrated with measurements of total N and P concentration in both mature and senesced leaves, and leaf mass per unit area (LMA). Contrary to what is known for other chronosequences, rates of photosynthesis and respiration did not decrease with increasing soil age and LMA along the Jurien Bay chronosequence. However, they increased when expressed per unit leaf P. Both N and P were used much more efficiently for photosynthesis on nutrient‐poor sites, in both Proteaceae and non‐Proteaceae species. Proteaceae had the fastest rate of photosynthesis per unit leaf P, followed by species that preferentially allocate P to mesophyll cells, rather than epidermal cells. Synthesis. Our results show that with declining soil P availability, photosynthetic P‐use efficiency of all investigated species from different families increased. Plants growing on the oldest, most nutrient‐impoverished soils exhibited similar rates of CO₂ exchange as plants growing on more nutrient‐rich younger soils, and extraordinarily high photosynthetic P‐use efficiency. This indicates convergence in leaf traits related to photosynthetic nutrient use on severely P‐impoverished sites.
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Calcium modulates leaf cell-specific phosphorus allocation in Proteaceae from south-western Australia
Journal of experimental botany, 2019Co-Authors: Patrick E. Hayes, Caio Guilherme Pereira, Peta L Clode, Hans LambersAbstract:Over 650 Proteaceae occur in south-western Australia, contributing to the region's exceptionally high biodiversity. Most Proteaceae occur exclusively on severely nutrient-impoverished, acidic soils (calcifuge), whilst only few also occur on young, calcareous soils (soil-indifferent), higher in calcium (Ca) and phosphorus (P). The calcifuge habit of Proteaceae is explained by Ca-enhanced P toxicity, putatively linked to the leaf cell-specific allocation of Ca and P. Separation of these elements is essential to avoid the deleterious precipitation of Ca-phosphate. We used quantitative X-ray microanalysis to determine leaf cell-specific nutrient concentrations of two calcifuge and two soil-indifferent Proteaceae grown in hydroponics at a range of Ca and P concentrations. Calcium enhanced the preferential allocation of P to palisade mesophyll (PM) cells under high P conditions, without a significant change in whole leaf [P]. Calcifuges showed a greater PM [P] compared with soil-indifferent species, corresponding to their greater sensitivity. This study advances our mechanistic understanding of Ca-enhanced P toxicity, supporting the proposed model, and demonstrating its role in the calcifuge distribution of Proteaceae. This furthers our understanding of nutrient interactions at the cellular level and highlights its importance to plant functioning.
Alejandra Zúñiga-feest - One of the best experts on this subject based on the ideXlab platform.
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Ecophysiological Performance of Proteaceae Species From Southern South America Growing on Substrates Derived From Young Volcanic Materials.
Frontiers in plant science, 2021Co-Authors: Mabel Delgado, Susana Valle, Marjorie Reyes-díaz, Patricio J. Barra, Alejandra Zúñiga-feest, S. Ruiz, Ariana Bertin-benavides, M. Pereira, Hans LambersAbstract:Southern South American Proteaceae thrive on young volcanic substrates, which are extremely low in plant-available phosphorus (P). Most Proteaceae exhibit a nutrient-acquisition strategy based on the release of carboxylates from specialized roots, named cluster roots (CR). Some Proteaceae colonize young volcanic substrates which has been related to CR functioning. However, physiological functioning of other Proteaceae on recent volcanic substrates is unknown. We conducted an experiment with seedlings of five Proteaceae (Gevuina avellana, Embothrium coccineum, Lomatia hirsuta, L. ferruginea, and L. dentata) grown in three volcanic materials. Two of them are substrates with very low nutrient concentrations, collected from the most recent deposits of the volcanoes Choshuenco and Calbuco (Chile). The other volcanic material corresponds to a developed soil that exhibits a high nutrient availability. We assessed morphological responses (i.e., height, biomass, and CR formation), seed and leaf macronutrient and micronutrient concentrations and carboxylates exuded by roots. The results show that G. avellana was less affected by nutrient availability of the volcanic substrate, probably because it had a greater nutrient content in its seeds and produced large CR exuding carboxylates that supported their initial growth. Embothrium coccineum exhibited greater total plant height and leaf P concentration than Lomatia species. In general, in all species leaf macronutrient concentrations were reduced on nutrient-poor volcanic substrates, while leaf micronutrient concentrations were highly variable depending on species and volcanic material. We conclude that Proteaceae from temperate rainforests differ in their capacity to grow and acquire nutrients from young and nutrient-poor volcanic substrates. The greater seed nutrient content, low nutrient requirements (only for G. avellana) and ability to mobilize nutrients help explain why G. avellana and E. coccineum are better colonizers of recent volcanic substrates than Lomatia species.
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New aluminum hyperaccumulator species of the Proteaceae family from southern South America
Plant and Soil, 2019Co-Authors: Mabel Delgado, Susana Valle, Marjorie Reyes-díaz, Patricio J. Barra, Alejandra Zúñiga-feestAbstract:Considering that some members of the Proteaceae family are aluminum (Al) and manganese (Mn)–hyperaccumulating species, we aimed to evaluate the presence of the metal hyperaccumulation trait in the Proteaceae family inhabiting southern South America. We also questioned whether other metals (e.g. iron (Fe), copper (Cu) and zinc (Zn)) are hyperaccumulated in the leaves of these species. Mature and senesced leaves of the six Proteaceae species (Embothrium coccineum, Gevuina avellana, Orites myrtoidea, Lomatia hirsuta, L. ferruginea, and L. dentata) as well as soil samples were collected at nine sites along a very extensive latitudinal gradient in southern Chile. Leaves and soil samples were used for chemical analyses. The results showed that G. avellana, L. dentata and O. myrtoidea are Al hyperaccumulators, with G. avellana showing the highest leaf Al concentrations. These leaf Al concentrations were independent of percentage of Al saturation and soil pH. No other metal (Fe, Cu, Zn, Mn) was hyperaccumulated in Proteaceae leaves. However, high Mn concentrations in leaves were found, especially in the species with the lowest values of Al concentrations in their leaves. Three of six species evaluated showed Al hyperaccumulation in their leaves, suggesting that this trait is common in Proteaceae from southern South America.
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Cluster root formation and function vary in two species with contrasting geographic ranges
Plant and Soil, 2019Co-Authors: Andrea Ávila-valdés, Frida I Piper, Alejandra Zúñiga-feestAbstract:AimsSouthern South American Proteaceae can occupy soils that are rich in total phosphorus (P) but poor in available P (for example volcanic soils) thanks to their cluster roots (CR), which mine soil P. However, some southern South American Proteaceae occur in a wide range of soil nutrition. We hypothesized that CR formation and function are more responsive to nutrient soil availability in the widely-distributed Embothrium coccineum than in the narrowly-distributed Orites myrtoidea , which exclusively occurs in recent volcanic depositions.MethodsSurvival, growth rate, CR formation (number, biomass) and function (carboxylate exudation, phosphatase activity) were evaluated in seedlings of both species after five months of growth in either a volcanic or organic substrate.ResultsE. coccineum exhibited full survival in both substrates, but had significantly lower growth, higher CR formation, higher CR citrate and malate exudation, and higher phosphatase activity in the volcanic substrate. By contrast, O. myrtoidea had similar growth rate in both substrates but 73% lower survival and null CR formation in the organic compared to the volcanic substrate.ConclusionsVariation in soil nutrient availability caused variation in growth and CR formation and function in a southern South American Proteaceae species of wider distribution, but not in a narrowly-distributed counterpart.
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Nutrient Use Efficiency of Southern South America Proteaceae Species. Are there General Patterns in the Proteaceae Family
Frontiers in Plant Science, 2018Co-Authors: Mabel Delgado, Susana Valle, Marjorie Reyes-díaz, Patricio J. Barra, Alejandra Zúñiga-feestAbstract:Plants from the Proteaceae family can thrive in old, impoverished soil with extremely low phosphorus (P) content, such as those typically found in South Western Australia (SWA) and South Africa. The South Western (SW) Australian Proteaceae species have developed strategies to deal with P scarcity, such as the high capacity to re-mobilize P from senescent to young leaves and the efficient use of P for carbon fixation. In Southern South America, six Proteaceae species grow in younger soils than those of SWA, with a wide variety of climatic and edaphic conditions. However, strategies in the nutrient use efficiency of Southern South (SS) American Proteaceae species growing in their natural ecosystems remain widely unknown. The aim of this study was to evaluate nutrient resorption efficiency and the photosynthetic nutrients use efficiency by SS American Proteaceae species, naturally growing in different sites along a very extensive latitudinal gradient. Mature and senescent leaves of the six SS American Proteaceae species (Embothrium coccineum, Gevuina avellana, Orites myrtoidea Lomatia hirsuta, L. ferruginea and L. dentata), as well as, soil samples were collected in nine sites from southern Chile and were subjected to chemical analyses. Nutrient resorption (P and nitrogen) efficiency in leaves was estimated in all species inhabiting the nine sites evaluated, whereas, the photosynthetic P use efficiency (PPUE) and photosynthetic nitrogen (N) use efficiency (PNUE) per leaf unit were determined in two sites with contrasting nutrient availability. Our study exhibit for the first time a data set related to nutrient use efficiency in the leaves of the six SS American Proteaceae, revealing that for all species and sites, P and N resorption efficiencies were on average 47.7% and 50.6%, respectively. No correlation was found between leaf nutrient (P and N) resorption efficiency and soil attributes. Further, different responses in PPUE and PNUE were found among species and, contrary to our expectations, a higher nutrient use efficiency in the nutrient poorest soil was not found. We conclude that SS American Proteaceae species did not show a general pattern in the nutrient use efficiency among them neither with others Proteaceae species reported in the literature.
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Table_1_Nutrient Use Efficiency of Southern South America Proteaceae Species. Are there General Patterns in the Proteaceae Family?.docx
2018Co-Authors: Mabel Delgado, Susana Valle, Marjorie Reyes-díaz, Patricio J. Barra, Alejandra Zúñiga-feestAbstract:Plants from the Proteaceae family can thrive in old, impoverished soil with extremely low phosphorus (P) content, such as those typically found in South Western Australia (SWA) and South Africa. The South Western (SW) Australian Proteaceae species have developed strategies to deal with P scarcity, such as the high capacity to re-mobilize P from senescent to young leaves and the efficient use of P for carbon fixation. In Southern South America, six Proteaceae species grow in younger soils than those of SWA, with a wide variety of climatic and edaphic conditions. However, strategies in the nutrient use efficiency of Southern South (SS) American Proteaceae species growing in their natural ecosystems remain widely unknown. The aim of this study was to evaluate nutrient resorption efficiency and the photosynthetic nutrients use efficiency by SS American Proteaceae species, naturally growing in different sites along a very extensive latitudinal gradient. Mature and senescent leaves of the six SS American Proteaceae species (Embothrium coccineum, Gevuina avellana, Orites myrtoidea Lomatia hirsuta, L. ferruginea, and L. dentata), as well as, soil samples were collected in nine sites from southern Chile and were subjected to chemical analyses. Nutrient resorption (P and nitrogen) efficiency in leaves was estimated in all species inhabiting the nine sites evaluated, whereas, the photosynthetic P use efficiency (PPUE) and photosynthetic nitrogen (N) use efficiency (PNUE) per leaf unit were determined in two sites with contrasting nutrient availability. Our study exhibit for the first time a data set related to nutrient use efficiency in the leaves of the six SS American Proteaceae, revealing that for all species and sites, P and N resorption efficiencies were on average 47.7 and 50.6%, respectively. No correlation was found between leaf nutrient (P and N) resorption efficiency and soil attributes. Further, different responses in PPUE and PNUE were found among species and, contrary to our expectations, a higher nutrient use efficiency in the nutrient poorest soil was not found. We conclude that SS American Proteaceae species did not show a general pattern in the nutrient use efficiency among them neither with others Proteaceae species reported in the literature.
Mabel Delgado - One of the best experts on this subject based on the ideXlab platform.
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Ecophysiological Performance of Proteaceae Species From Southern South America Growing on Substrates Derived From Young Volcanic Materials.
Frontiers in plant science, 2021Co-Authors: Mabel Delgado, Susana Valle, Marjorie Reyes-díaz, Patricio J. Barra, Alejandra Zúñiga-feest, S. Ruiz, Ariana Bertin-benavides, M. Pereira, Hans LambersAbstract:Southern South American Proteaceae thrive on young volcanic substrates, which are extremely low in plant-available phosphorus (P). Most Proteaceae exhibit a nutrient-acquisition strategy based on the release of carboxylates from specialized roots, named cluster roots (CR). Some Proteaceae colonize young volcanic substrates which has been related to CR functioning. However, physiological functioning of other Proteaceae on recent volcanic substrates is unknown. We conducted an experiment with seedlings of five Proteaceae (Gevuina avellana, Embothrium coccineum, Lomatia hirsuta, L. ferruginea, and L. dentata) grown in three volcanic materials. Two of them are substrates with very low nutrient concentrations, collected from the most recent deposits of the volcanoes Choshuenco and Calbuco (Chile). The other volcanic material corresponds to a developed soil that exhibits a high nutrient availability. We assessed morphological responses (i.e., height, biomass, and CR formation), seed and leaf macronutrient and micronutrient concentrations and carboxylates exuded by roots. The results show that G. avellana was less affected by nutrient availability of the volcanic substrate, probably because it had a greater nutrient content in its seeds and produced large CR exuding carboxylates that supported their initial growth. Embothrium coccineum exhibited greater total plant height and leaf P concentration than Lomatia species. In general, in all species leaf macronutrient concentrations were reduced on nutrient-poor volcanic substrates, while leaf micronutrient concentrations were highly variable depending on species and volcanic material. We conclude that Proteaceae from temperate rainforests differ in their capacity to grow and acquire nutrients from young and nutrient-poor volcanic substrates. The greater seed nutrient content, low nutrient requirements (only for G. avellana) and ability to mobilize nutrients help explain why G. avellana and E. coccineum are better colonizers of recent volcanic substrates than Lomatia species.
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New aluminum hyperaccumulator species of the Proteaceae family from southern South America
Plant and Soil, 2019Co-Authors: Mabel Delgado, Susana Valle, Marjorie Reyes-díaz, Patricio J. Barra, Alejandra Zúñiga-feestAbstract:Considering that some members of the Proteaceae family are aluminum (Al) and manganese (Mn)–hyperaccumulating species, we aimed to evaluate the presence of the metal hyperaccumulation trait in the Proteaceae family inhabiting southern South America. We also questioned whether other metals (e.g. iron (Fe), copper (Cu) and zinc (Zn)) are hyperaccumulated in the leaves of these species. Mature and senesced leaves of the six Proteaceae species (Embothrium coccineum, Gevuina avellana, Orites myrtoidea, Lomatia hirsuta, L. ferruginea, and L. dentata) as well as soil samples were collected at nine sites along a very extensive latitudinal gradient in southern Chile. Leaves and soil samples were used for chemical analyses. The results showed that G. avellana, L. dentata and O. myrtoidea are Al hyperaccumulators, with G. avellana showing the highest leaf Al concentrations. These leaf Al concentrations were independent of percentage of Al saturation and soil pH. No other metal (Fe, Cu, Zn, Mn) was hyperaccumulated in Proteaceae leaves. However, high Mn concentrations in leaves were found, especially in the species with the lowest values of Al concentrations in their leaves. Three of six species evaluated showed Al hyperaccumulation in their leaves, suggesting that this trait is common in Proteaceae from southern South America.
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Nutrient Use Efficiency of Southern South America Proteaceae Species. Are there General Patterns in the Proteaceae Family
Frontiers in Plant Science, 2018Co-Authors: Mabel Delgado, Susana Valle, Marjorie Reyes-díaz, Patricio J. Barra, Alejandra Zúñiga-feestAbstract:Plants from the Proteaceae family can thrive in old, impoverished soil with extremely low phosphorus (P) content, such as those typically found in South Western Australia (SWA) and South Africa. The South Western (SW) Australian Proteaceae species have developed strategies to deal with P scarcity, such as the high capacity to re-mobilize P from senescent to young leaves and the efficient use of P for carbon fixation. In Southern South America, six Proteaceae species grow in younger soils than those of SWA, with a wide variety of climatic and edaphic conditions. However, strategies in the nutrient use efficiency of Southern South (SS) American Proteaceae species growing in their natural ecosystems remain widely unknown. The aim of this study was to evaluate nutrient resorption efficiency and the photosynthetic nutrients use efficiency by SS American Proteaceae species, naturally growing in different sites along a very extensive latitudinal gradient. Mature and senescent leaves of the six SS American Proteaceae species (Embothrium coccineum, Gevuina avellana, Orites myrtoidea Lomatia hirsuta, L. ferruginea and L. dentata), as well as, soil samples were collected in nine sites from southern Chile and were subjected to chemical analyses. Nutrient resorption (P and nitrogen) efficiency in leaves was estimated in all species inhabiting the nine sites evaluated, whereas, the photosynthetic P use efficiency (PPUE) and photosynthetic nitrogen (N) use efficiency (PNUE) per leaf unit were determined in two sites with contrasting nutrient availability. Our study exhibit for the first time a data set related to nutrient use efficiency in the leaves of the six SS American Proteaceae, revealing that for all species and sites, P and N resorption efficiencies were on average 47.7% and 50.6%, respectively. No correlation was found between leaf nutrient (P and N) resorption efficiency and soil attributes. Further, different responses in PPUE and PNUE were found among species and, contrary to our expectations, a higher nutrient use efficiency in the nutrient poorest soil was not found. We conclude that SS American Proteaceae species did not show a general pattern in the nutrient use efficiency among them neither with others Proteaceae species reported in the literature.
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Table_1_Nutrient Use Efficiency of Southern South America Proteaceae Species. Are there General Patterns in the Proteaceae Family?.docx
2018Co-Authors: Mabel Delgado, Susana Valle, Marjorie Reyes-díaz, Patricio J. Barra, Alejandra Zúñiga-feestAbstract:Plants from the Proteaceae family can thrive in old, impoverished soil with extremely low phosphorus (P) content, such as those typically found in South Western Australia (SWA) and South Africa. The South Western (SW) Australian Proteaceae species have developed strategies to deal with P scarcity, such as the high capacity to re-mobilize P from senescent to young leaves and the efficient use of P for carbon fixation. In Southern South America, six Proteaceae species grow in younger soils than those of SWA, with a wide variety of climatic and edaphic conditions. However, strategies in the nutrient use efficiency of Southern South (SS) American Proteaceae species growing in their natural ecosystems remain widely unknown. The aim of this study was to evaluate nutrient resorption efficiency and the photosynthetic nutrients use efficiency by SS American Proteaceae species, naturally growing in different sites along a very extensive latitudinal gradient. Mature and senescent leaves of the six SS American Proteaceae species (Embothrium coccineum, Gevuina avellana, Orites myrtoidea Lomatia hirsuta, L. ferruginea, and L. dentata), as well as, soil samples were collected in nine sites from southern Chile and were subjected to chemical analyses. Nutrient resorption (P and nitrogen) efficiency in leaves was estimated in all species inhabiting the nine sites evaluated, whereas, the photosynthetic P use efficiency (PPUE) and photosynthetic nitrogen (N) use efficiency (PNUE) per leaf unit were determined in two sites with contrasting nutrient availability. Our study exhibit for the first time a data set related to nutrient use efficiency in the leaves of the six SS American Proteaceae, revealing that for all species and sites, P and N resorption efficiencies were on average 47.7 and 50.6%, respectively. No correlation was found between leaf nutrient (P and N) resorption efficiency and soil attributes. Further, different responses in PPUE and PNUE were found among species and, contrary to our expectations, a higher nutrient use efficiency in the nutrient poorest soil was not found. We conclude that SS American Proteaceae species did not show a general pattern in the nutrient use efficiency among them neither with others Proteaceae species reported in the literature.
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divergent functioning of Proteaceae species the south american embothrium coccineum displays a combination of adaptive traits to survive in high phosphorus soils
Functional Ecology, 2014Co-Authors: Mabel Delgado, L D B Suriyagoda, Alejandra Zunigafeest, Fernando Borie, Hans LambersAbstract:Summary 1. Proteaceae species in south-western Australia thrive on phosphorus-impoverished soils, employing a phosphorus-mining strategy involving carboxylate-releasing cluster roots. Some develop symptoms of phosphorus toxicity at slightly elevated soil phosphorus concentrations, due to their low capacity to down-regulate phosphorus uptake. In contrast, Proteaceae species in Chile, e.g. Embothrium coccineum J.R. Forst. & G. Forst., occur on volcanic soils, which contain high levels of total phosphorus, but phosphorus availability is low. 2. We hypothesised that the functioning of cluster roots of E. coccineum differs from that of south-western Australian Proteaceae species, in accordance with the difference in soil phosphorus status. With more phosphorus to be gained from the soil with high levels of total phosphorus, we expect less investment in biomass and more release of carboxylates. Furthermore, we hypothesised that E. coccineum regulates its phosphorus-uptake capacity, avoiding phosphorus toxicity when grown at elevated phosphorus levels. To test these hypotheses, E. coccineum seedlings were grown at a range of phosphorus supplies in nutrient solution. 3. We show that E. coccineum allocated at least five times less biomass to cluster roots that released at least nine times more carboxylates per unit cluster root weight compared with south-western Australian species (e.g. Banksia, Hakea). The highest phosphorus supply caused a growth inhibition and high leaf phosphorus concentration, without symptoms of phosphorus toxicity. We accept our hypotheses on the functioning of cluster roots and the high capacity to reduce the net phosphorus uptake in plants grown at a high-phosphorus supply. 4. This novel combination of traits indicates divergent functioning of Proteaceae species from southern South America, exposed to frequent phosphorus input due to volcanic activity, in contrast with the functioning of south-western Australian Proteaceae species that thrive on severely phosphorus-impoverished soils. These traits could explain the functioning of E. coccineum on soils that are rich in total phosphorus, but with a low concentration of available phosphorus.
Pedro W. Crous - One of the best experts on this subject based on the ideXlab platform.
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Species of the Colletotrichum gloeosporioides complex associated with anthracnose diseases of Proteaceae
Fungal Diversity, 2013Co-Authors: Fang Liu, Ulrike Damm, Lei Cai, Pedro W. CrousAbstract:Anthracnose disease of Proteaceae has in the past chiefly been attributed to infections by C. acutatum, C. boninense and C. gloeosporioides. In the present study, a multi-locus phylogenetic analysis (ACT, CAL, CHS-1, GAPDH, GS, ITS, TUB2) revealed that strains of the C. gloeosporioides complex associated with Proteaceae belong to at least six species. These include C. alienum, C. aotearoa, C. kahawae (subsp. ciggaro), C. siamense, and two new taxa, C. proteae and C. grevilleae. The most economically important pathogen of Proteaceae seems to be C. alienum, and not C. gloeosporioides as previously reported. All taxa associated with Proteaceae are morphologically described on different media in culture, except strains of C. siamense, which proved to be sterile. Furthermore, C. populi is synonymised with C. aenigma.
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Ilyonectria black foot rot associated with Proteaceae
Australasian Plant Pathology, 2013Co-Authors: Lorenzo Lombard, Carolien M. Bezuidenhout, Pedro W. CrousAbstract:Proteaceae is an important component of the South African cut flower industry. Propagation of these woody plants using vegetative cuttings is, however, hampered by fungal infections initiated in the nursery. Recently black foot rot disease symptoms were observed on vegetative cuttings of Protea and Leucospermum in a fynbos nursery near Stanford, Western Cape Province, South Africa. Isolations from symptomatic plant material revealed several isolates of Ilyonectria , which were identified as I. macrodidyma , I. torresensis and four novel taxa described here as I. capensis , I. leucospermi , I. protearum and I. vredehoekensis. Species were characterised based on DNA phylogenetic inference and morphological comparisons. Furthermore, pathogenicity tests were conducted, which confirmed all six Ilyonectria species capable of causing black foot rot of Proteaceae . Other than the novel plant pathogenic species described here, this study also represents the first report of black foot rot disease associated with the cultivation of Proteaceae cut flowers.
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Species of Botryosphaeriaceae occurring on Proteaceae.
Persoonia, 2008Co-Authors: Seonju Marincowitz, Michael J. Wingfield, Johannes Z. Groenewald, Pedro W. CrousAbstract:The Botryosphaeriaceae includes several species that are serious canker and leaf pathogens of Proteaceae. In the present study, sequence data for the ITS nrDNA region were used in conjunction with morphological observations to resolve the taxonomy of species of Botryosphaeriaceae associated with Proteaceae. Neofusicoccum luteum was confirmed from Buckinghamia and Banksia in Australia, and on Protea cynaroides in South Africa. A major pathogen of Banksia coccinea in Australia was shown to be N. australe and not N. luteum as previously reported. Neofusicoccum protearum was previously reported on Proteaceae from Australia, Madeira, Portugal and South Africa, and is shown here to also occur in Hawaii and Tenerife (Canary Islands). Furthermore, several previous records of N. ribis on Proteaceae were shown to be N. parvum. Saccharata capensis is described as a new species that is morphologically similar to S. proteae. There is no information currently available regarding its potential importance as plant pathogen and pathogenicity tests should be conducted with it in the future.
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Host specificity and speciation of Mycosphaerella and Teratosphaeria species associated with leaf spots of Proteaceae.
Persoonia, 2008Co-Authors: Pedro W. Crous, Brett A. Summerell, Lizel Mostert, Johannes Z. GroenewaldAbstract:Species of Mycosphaerella and Teratosphaeria represent important foliicolous pathogens of Proteaceae. Presently approximately 40 members of these genera (incl. anamorphs) have been recorded from Proteaceae, though the majority are not known from culture, and have never been subjected to DNA sequence analysis. During the course of this study, epitypes were designated for several important species, namely Batcheloromyces leucadendri, B. proteae, Catenulostroma macowanii, Mycosphaerella marksii, Teratosphaeria bellula, T. jonkershoekensis, T. parva, and T. proteae-arboreae. Several species were also newly described, namely Batcheloromyces sedgefieldii, Catenulostroma wingfieldii, Dissoconium proteae, Teratosphaeria persoonii, T. knoxdavesii, and T. marasasii. Although accepted as being highly host specific, some species were shown to have wider host ranges, such as M. communis (Eucalyptus, Protea), M. konae (Leucospermum, Eucalyptus), M. marksii (Eucalyptus, Leucadendron), T. associata (Eucalyptus, Protea), and T. parva (Eucalyptus, Protea), which in most cases were found to co-occur with other species of Mycosphaerella or Teratosphaeria on Proteaceae. Furthermore, earlier records of T. jonkershoekensis on Proteaceae in Australia were shown to be representative of two recently described species, T. associata and T. maxii. A phenomenon of underdeveloped, or micro-ascospores was also newly observed in asci of T. maculiformis and T. proteae-arboreae. The exact purpose of asci with two distinct types of ascospores remains to be clarified, as both types were observed to germinate on agar.
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Characterization of Colletotrichum species associated with diseases of Proteaceae
Mycologia, 2004Co-Authors: Carolien M. Lubbe, S. Denman, Johannes Z. Groenewald, Paul F. Cannon, S. C. Lamprecht, Pedro W. CrousAbstract:Colletotrichum spp. are known to occur on and cause diseases of Proteaceae, but their identities are confused and poorly understood. The aim of the present study thus was to identify accurately the Col- letotrichum spp. associated with diseases of cultivated Proteaceae. Colletotrichum spp. associated with pro- teaceous hosts growing in various parts of the world were identified based on morphology, sequence data of the internal transcribed spacer region (ITS-1, ITS- 2), the 5.8S gene, and partial sequences of the b- tubulin gene. Four species of Colletotrichum were found to be associated with Proteaceae. Colletotri- chum gloeosporioides, a cosmopolitan species known to occur on numerous hosts, was isolated from Protea cynaroides cultivated in South Africa and Zimbabwe, and from a Leucospermum sp. in Portugal. A recently described species, C. boninense was associated with Zimbabwean and Australian Proteaceae but also oc- curred on a Eucalyptus sp. in South Africa. This rep- resents a major geographical and host extension for the species and a description of the African strains is
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Species of Botryosphaeriaceae occurring on Proteaceae.
Persoonia, 2008Co-Authors: Seonju Marincowitz, Michael J. Wingfield, Johannes Z. Groenewald, Pedro W. CrousAbstract:The Botryosphaeriaceae includes several species that are serious canker and leaf pathogens of Proteaceae. In the present study, sequence data for the ITS nrDNA region were used in conjunction with morphological observations to resolve the taxonomy of species of Botryosphaeriaceae associated with Proteaceae. Neofusicoccum luteum was confirmed from Buckinghamia and Banksia in Australia, and on Protea cynaroides in South Africa. A major pathogen of Banksia coccinea in Australia was shown to be N. australe and not N. luteum as previously reported. Neofusicoccum protearum was previously reported on Proteaceae from Australia, Madeira, Portugal and South Africa, and is shown here to also occur in Hawaii and Tenerife (Canary Islands). Furthermore, several previous records of N. ribis on Proteaceae were shown to be N. parvum. Saccharata capensis is described as a new species that is morphologically similar to S. proteae. There is no information currently available regarding its potential importance as plant pathogen and pathogenicity tests should be conducted with it in the future.
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Host specificity and speciation of Mycosphaerella and Teratosphaeria species associated with leaf spots of Proteaceae.
Persoonia, 2008Co-Authors: Pedro W. Crous, Brett A. Summerell, Lizel Mostert, Johannes Z. GroenewaldAbstract:Species of Mycosphaerella and Teratosphaeria represent important foliicolous pathogens of Proteaceae. Presently approximately 40 members of these genera (incl. anamorphs) have been recorded from Proteaceae, though the majority are not known from culture, and have never been subjected to DNA sequence analysis. During the course of this study, epitypes were designated for several important species, namely Batcheloromyces leucadendri, B. proteae, Catenulostroma macowanii, Mycosphaerella marksii, Teratosphaeria bellula, T. jonkershoekensis, T. parva, and T. proteae-arboreae. Several species were also newly described, namely Batcheloromyces sedgefieldii, Catenulostroma wingfieldii, Dissoconium proteae, Teratosphaeria persoonii, T. knoxdavesii, and T. marasasii. Although accepted as being highly host specific, some species were shown to have wider host ranges, such as M. communis (Eucalyptus, Protea), M. konae (Leucospermum, Eucalyptus), M. marksii (Eucalyptus, Leucadendron), T. associata (Eucalyptus, Protea), and T. parva (Eucalyptus, Protea), which in most cases were found to co-occur with other species of Mycosphaerella or Teratosphaeria on Proteaceae. Furthermore, earlier records of T. jonkershoekensis on Proteaceae in Australia were shown to be representative of two recently described species, T. associata and T. maxii. A phenomenon of underdeveloped, or micro-ascospores was also newly observed in asci of T. maculiformis and T. proteae-arboreae. The exact purpose of asci with two distinct types of ascospores remains to be clarified, as both types were observed to germinate on agar.
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Characterization of Colletotrichum species associated with diseases of Proteaceae
Mycologia, 2004Co-Authors: Carolien M. Lubbe, S. Denman, Johannes Z. Groenewald, Paul F. Cannon, S. C. Lamprecht, Pedro W. CrousAbstract:Colletotrichum spp. are known to occur on and cause diseases of Proteaceae, but their identities are confused and poorly understood. The aim of the present study thus was to identify accurately the Col- letotrichum spp. associated with diseases of cultivated Proteaceae. Colletotrichum spp. associated with pro- teaceous hosts growing in various parts of the world were identified based on morphology, sequence data of the internal transcribed spacer region (ITS-1, ITS- 2), the 5.8S gene, and partial sequences of the b- tubulin gene. Four species of Colletotrichum were found to be associated with Proteaceae. Colletotri- chum gloeosporioides, a cosmopolitan species known to occur on numerous hosts, was isolated from Protea cynaroides cultivated in South Africa and Zimbabwe, and from a Leucospermum sp. in Portugal. A recently described species, C. boninense was associated with Zimbabwean and Australian Proteaceae but also oc- curred on a Eucalyptus sp. in South Africa. This rep- resents a major geographical and host extension for the species and a description of the African strains is
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Circumscription of Botryosphaeria species associated with Proteaceae based on morphology and DNA sequence data
Mycologia, 2003Co-Authors: S. Denman, Pedro W. Crous, Johannes Z. Groenewald, Bernard Slippers, Brenda D. Wingfield, Michael J. WingfieldAbstract:Botryosphaeria spp. occur on and cause dis- eases of Proteaceae, but accurate identification has been problematic due to the lack of clear species cir- cumscriptions of members of this genus. In this study, 46 isolates of Botryosphaeria from proteaceous hosts growing in various parts of the world were studied, using morphology, cultural characters and sequence data from the ITS region of the rDNA operon. Five Botryosphaeria spp. were found to be associated with Proteaceae. Botryosphaeria lutea was isolated from Banksia and Buckinghamia spp. in Australia, and a single isolate was obtained from Protea cynaroides in South Africa. Botryosphaeria proteae was associated only with South African Proteaceae, but occurred in many parts of the world. Another Botryosphaeria sp. that occurred exclusively on South African Protea- ceae represents a new taxon that is described as B. protearum. This pathogen was found on South Afri- can Proteaceae cultivated in Australia; Hawaii; Por- tugal, including the Madeira Islands; and South Af- rica. Botryosphaeria ribis was associated with both South African and Australian Proteaceae and was iso- lated from material collected in Australia, Hawaii and Zimbabwe. A single occurrence of B. obtusa as an endophyte was recorded from P. magnifica in South Africa. In addition to providing a taxonomic overview of Botryosphaeria spp. associated with Proteaceae, this paper clarifies for the first time the global distribu- tion of these species. A key also is provided to facili- tate their identification. A large number of new host
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Rhynchostomatoid fungi occurring on Proteaceae.
Mycologia, 2003Co-Authors: Seonju Lee, Joanne E. Taylor, Johannes Z. Groenewald, Francois Roets, Pedro W. CrousAbstract:A new ascomycete fungus, with long-necked perithecia having central ostioles and striate ascospores, was isolated from flowerheads of Protea burchellii and P. laurifolia in South Africa and is described here as Rhynchostoma proteae sp. nov. Sequence data obtained from the small-subunit ribosomal DNA (SSU nrDNA) place this fungus with 100% bootstrap support in a clade containing the type species of Rhynchostoma, R. minutum. A similar fungus with verruculose ascospores also was observed on a member of the Proteaceae from Australia, Lomatia polymorpha, which is described here as Rhynchomeliola lomatiae sp. nov. These two species are illustrated and contrasted with a third species from Proteaceae, Rhynchomeliola australiense, known from Grevillea in Australia.
