ORCID Profile
0000-0002-8879-2449
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Publisher: Elsevier BV
Date: 11-2022
Publisher: Wiley
Date: 2007
Abstract: The relationships between various leaf functional traits that are important in plant growth (e.g., specific leaf area) have been investigated in recent studies however, research in this context on plants that are highly protected by chemical defences, particularly resource-demanding nitrogen-based defence, is lacking. We collected leaves from cyanogenic (N-defended) Beilschmiedia collina B. Hyland and acyanogenic (C-defended) Beilschmiedia tooram (F. M. Bailey) B. Hyland at high- and low-soil nutrient sites in two consecutive years that varied significantly in rainfall. We then measured the relationships between chemical defence and morphological and functional leaf traits under the different environmental conditions. We found that the two species differed significantly in their resource allocation to defence as well as leaf morphology and function. The N defended species had a higher leaf nitrogen concentration, whereas the C-defended species had higher amounts of C-based chemical defences (i.e., total phenolics and condensed tannins). The C-defended species also tended to have higher force to fracture and increased leaf toughness. In B. collina, cyanogenic glycoside concentration was higher with higher rainfall, but not with higher soil nutrients. Total phenolic concentration was higher at the high soil nutrient site in B. tooram, but lower in B. collina however, with higher rainfall an increase was found in B. tooram, while phenolics decreased in B. collina. Condensed tannin concentration decreased in both species with rainfall and nutrient availability. We conclude that chemical defence is correlated with leaf functional traits and that variation in environmental resources affects this correlation.
Publisher: Elsevier BV
Date: 08-2017
Publisher: Frontiers Media SA
Date: 26-04-2017
Publisher: Oxford University Press (OUP)
Date: 08-07-2010
Abstract: This review is focused on woody legumes from the southern continents. We highlight that the evolution of the Caesalpinioideae and Mimosoideae with old soils, with variable supplies of water and also with fire has produced a suite of advantageous physiological characteristics. These include good potential for nitrogen fixation and mechanisms for acquiring P. The latter includes the ability to form cluster roots and produce extracellular phosphatase enzymes. Further, many of the species in these subfamilies are known to synthesize in significant amounts osmotically compatible solutes, such as pinitol and other cyclitols olyols, that help them cope with even severe drought conditions. In many cases, these species regenerate prolifically after fire from seed. Such species and their beneficial characters can now be better exploited to help sequester carbon, provide key nutrients such as nitrogen and phosphorus for companion crops and other plants and provide feedstocks for a range of industries, including energy industries.
Publisher: Oxford University Press (OUP)
Date: 23-06-2010
Abstract: Plants have evolved a vast array of defence mechanisms to avoid or minimize damage caused by herbivores and pathogens. The costs and benefits of defences are thought to vary with the availability of resources, herbivore pressure and plant functional traits. We investigated the resource (nitrogen) and growth cost of deploying cyanogenic glycosides in seedlings of Eucalyptus cladocalyx (Myrtaceae). To do this, we grew the plants under a range of soil N conditions, from levels that were limiting for growth to those that were saturating for growth, and we measured correlations between foliar chemical and performance attributes. Within each N treatment, we found evidence that, for every N invested in cyanogenic glycosides, additional N is added to the leaf. For the lowest N treatment, the additional N was less than one per cyanogenic glycoside, rising to some two Ns for the other treatments. The interaction between cyanogenic glycosides and both condensed tannins and total phenolic compounds was also examined, but we did not detect correlations between these compounds under constant leaf N concentrations. Finally, we did not detect a correlation between net assimilation rate, relative growth rate and cyanogenic glycoside concentrations under any soil N treatment. We conclude that the growth cost of cyanogenic glycosides was likely too low to detect and that it was offset to some degree by additional N that was allocated alongside the cyanogenic glycosides.
Publisher: CSIRO Publishing
Date: 2006
DOI: 10.1071/FP05305
Abstract: This study examined two aspects of cyanogenesis in Brombya platynema F. Muell. (Rutaceae), a subcanopy tree endemic to tropical rainforest in far north Queensland, Australia. First, cyanogenic glycosides in foliage were fractionated and identified. The rare meta-hydroxylated cyanogenic glycoside, holocalin, was identified as the principal cyanogen, and traces of prunasin and amygdalin were detected. This is the first characterisation of cyanogenic constituents within the genus, and to the authors’ knowledge, only the third within the Rutaceae, and the order Rutales. Second, variation in cyanogenic glycoside content within a population of B. platynema in lowland tropical rainforest was quantified. Both qualitative and quantitative polymorphism for cyanogenesis was identified. Interestingly, ~57% of in iduals were considered acyanogenic, with concentrations of cyanogenic glycosides less than 8 μg CN g–1 DW. Among cyanogenic in iduals there was substantial quantitative variation in cyanogenic glycoside concentration, which varied from 10.5 to 1285.9 μg CN g–1 DW. This high frequency of acyanogenic in iduals is contrasted with the apparent absence of the acyanogenesis among populations of other tropical rainforest tree species. In the high herbivory environment of the tropical rainforest, this frequency of acyanogenesis among cyanogenic tropical tree taxa is unique.
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