Response of the Invasive Cat's Claw Creeper,Macfadyena unguis-cati(Bignoniaceae), to Simulated and Actual Defoliation byCharidotis auroguttata(Coleoptera: Chrysomelidae)

The specialist tingid, Carvalhotingis visenda, is a biological control agent for cat's claw creeper, Macfadyena unguis-cati (Bignoniaceae). Cat's claw creeper is an invasive liana with a wide climatic tolerance, and for biological control to be effective the tingid must survive and develop over a range of temperatures. We evaluated the effect of constant temperatures (0-45 degrees C) on the survival and development of C. visenda. Adults showed tolerance for wider temperature ranges (0-45 degrees C), but oviposition, egg hatching and nymphal development were all affected by both high (>30 degrees C) and low (<20 degrees C) temperatures. Temperatures between 20 degrees C and 30 degrees C are the most favourable for adult survival, oviposition, egg hatching and nymphal development. The ability of adults and nymphs to survive for a few days at high (40 degrees C and 45 degrees C) and low (0 degrees C and 5 degrees C) temperatures suggest that extreme temperature events, which usually occur for short durations (hours) in cat's claw creeper infested regions in Queensland and New South Wales states are not likely to affect the tingid population. The potential number of generations (egg to adult) the tingid can complete in a year in Australia ranged from three to eight, with more generations in Queensland than in New South Wales.

In classical weed biological control, assessing weed response to simulated herbivory is one option to assist in the prioritization of available agents and prediction of their potential efficacy. Previously reported simulated herbivory studies suggested that a specialist herbivore in the leaf-feeding guild is desirable as an effective biological control agent for cat's claw creeper Macfadyena unguis-cati (Bignoniaceae), an environmental weed that is currently a target for biological control. In this study, we tested (i) whether the results from glasshouse-based simulated herbivory can be used to prioritise potential biological control agents by evaluating the impact of a leaf-sucking tingid bug Carvalhotingis visenda (Drake & Hambleton) (Hemiptera: Tingidae) in quarantine; and (ii) the likely effectiveness of low- and high-densities of the leaf-sucking tingid after its release in the field. The results suggest that a single generation of C. visenda has the potential to reduce leaf chlorophyll content significantly, resulting in reduced plant height and leaf biomass. However, the impact of one generation of tingid herbivory on below-ground plant components, including the roots and tuber size and biomass, were not significant. These findings are consistent with results obtained from a simulated herbivory trial, highlighting the potential role of simulated herbivory studies in agent prioritisation.

The expanded growth model is developed to describe accumulation of plant biomass (Mg ha−1) and mineral elements (kg ha−1) in with calendar time (wk). Accumulation of plant biomass with calendar time occurs as a result of photosynthesis for green land-based plants. A corresponding accumulation of mineral elements such as nitrogen, phosphorus, and potassium occurs from the soil through plant roots. In this analysis, the expanded growth model is tested against high quality, published data on corn (Zea mays L.) growth. Data from a field study in South Carolina was used to evaluate the application of the model, where the planting time of April 2 in the field study maximized the capture of solar energy for biomass production. The growth model predicts a simple linear relationship between biomass yield and the growth quantifier, which is confirmed with the data. The growth quantifier incorporates the unit processes of distribution of solar energy which drives biomass accumulation by photosynthesis, partitioning of biomass between light-gathering and structural components of the plants, and an aging function. A hyperbolic relationship between plant nutrient uptake and biomass yield is assumed, and is confirmed for the mineral elements nitrogen (N), phosphorus (P), and potassium (K). It is concluded that the rate limiting process in the system is biomass accumulation by photosynthesis and that nutrient accumulation occurs in virtual equilibrium with biomass accumulation.

Introduced as an ornamental vine, cat’s claw creeper Dolichandra unguis-cati (syn. Macfadyena unguis-cati) has invaded coastal and subcoastal areas of subtropical eastern Australia. Two varieties have been indentified, one of which (‘short-pod’) is found throughout south-eastern Australia, while the other (‘long-pod’) appears to be restricted to several sites in south-eastern Queensland. We compared the growth and biomass allocation patterns of the two varieties in the field over a 22-month period to determine if a higher growth rate and/or more efficient allocation of biomass may contribute to this disparity in distribution. The long-pod variety produced greater aboveground and total biomass than the short-pod variety in both riparian and non-riparian zones. Belowground the two varieties produced a similar number of tubers and overall biomass, though the long-pod variety allocated a smaller portion of its carbon belowground. High growth rates and greater biomass allocation aboveground are characteristic of invasive species, allowing them to outcompete and crowd out existing vegetation. There was no significant site by variety interaction, an indication of consistency in variety performance across riparian and non-riparian sites. Results from our study suggest that differences in growth and biomass allocations are unlikely to have contributed to the disparity in distribution of the two varieties. Despite currently occupying a relatively small range, the long-pod variety may be a more adept invader than the short-pod variety, and could become more prevalent in the future.

Cat’s claw creeper vine, Dolichandra unguis-cati (L.) Lohmann (syn. Macfadyena unguis-cati (L.) Gentry) (Bignoniaceae), is a major environmental weed in Australia. Two distinct forms of this weed (‘long’ and ‘short’ pod), with differences in leaf morphology and fruit size, occur in Australia. The long pod form has only been reported in less than fifteen localities in the whole of south-east Queensland, while the short pod form is widely distributed in Queensland and New South Wales. This study sought to compare growth traits such as specific leaf area, relative growth rate, stem length, shoot/root ratio, tuber biomass and branching architecture between these forms. These traits were monitored under glasshouse conditions over a period of 18 months. Short pod exhibited higher values of relative growth rates, stem length, number of tubers and specific leaf area than long pod, but only after 10 months of plant growth. Prior to this, long and short pod did not differ significantly. Higher values for these traits have been described as characteristics of successful colonizers. Results from this study could partly explain why the short pod form is more widely distributed in Australia while long pod is confined to a few localities.

ABSTRACTAfforestation is one of the widely used methods of reclamation in cutaway peatlands where spontaneous revegetation is not feasible, but fertilization or liming is usually required to encourage the development of vegetation cover. Wood ash application increases planted tree biomass, but the role of spontaneously incoming species in early‐stage biomass accumulation is lesser known. The amount of below‐and aboveground biomass accumulation was evaluated in relation to the drainage ditch position (2 or 9 m from the ditch edge) and the amount of wood ash applied (0, 5, 10, or 15 megagrams ha−1) three years after fertilization. The biomass accumulation, species richness, and plant carbon and nitrogen ratio were positively impacted by wood ash treatment, but biomass allocation was species dependent: for all tree and herbaceous species with individual root systems, the proportion of biomass accumulated in roots was higher in the unfertilized group, but for Phragmites australis with a clonal root system, it was contrariwise. The application of 10 Mg ha−1 wood ash was the most productive, with an average of 485.0 g/m2 total plant dry biomass accumulation next to and 301.3 g/m2 further from the drainage ditch, compared to the unfertilized 36.8 g/m2 (2 m from ditch) and 13.9 g/m2 (9 m from ditch). During the initial vegetation establishment, herbaceous species comprised the majority of the biomass, primarily graminoids.

Cat's claw creeper, Dolichandra unguis‐cati (Bignoniaceae), a perennial woody vine native to tropical America, is a target for biological control in Australia and South Africa. The cat's claw creeper leaf‐tying moth Hypocosmia pyrochroma (Lepidoptera: Pyralidae) from tropical South America was released as a biological control agent for cat's claw creeper in Australia from 2007 to 2010. A total of 2,277 adults, 837 pupae and 77,250 larvae were released at 40 sites in Queensland and New South Wales. Releases were made mostly in open fields (85%), and at limited sites (15%) in insect‐proof cages erected over naturally occurring cat's claw creeper infestations in the field. Sampling was conducted annually in spring and autumn to monitor the establishment and dispersal of H. pyrochroma. Establishment of H. pyrochroma was first noticed in 2012 at three release sites and since then the number of established sites has increased to 80 in 2020. Establishment was evident on both ‘short‐pod’ and ‘long‐pod’ forms of cat's claw creeper and was more widespread in sites where releases were made within insect‐proof field cages (50%) than in sites with open field releases (9%). The moth was active from late spring to late autumn with peak larval activity in late summer. To date, all field establishments have been in areas predicted by a CLIMEX model as climatically suitable but restricted mostly to riparian environment (93% of establishment), where the moth has continued to spread from 1.5 to 23 km from release sites. In contrast, there is the only limited establishment and spread in non‐riparian corridors, highlighting the role of microclimate (riparian) as a limiting factor for establishment and spread. Future efforts will focus on redistribution of the agent to river/creek systems where the moth is currently not present.

El objetivo de esta investigación fue evaluar la respuesta de la papa (Solanum tuberosum) a la fertilización de nitrógeno (N), fósforo (P) y potasio (K), en la acumulación de biomasa, índice de cosecha y número de tubérculos bajo condiciones de hidroponía bajo invernadero. El diseño experimental utilizado fue el San Cristóbal, con 12 tratamientos. Las variables que se evaluaron fueron: biomasa de hoja, tallo, raíz, estolón y tubérculo, índice de cosecha y número de tubérculos. La distribución de biomasa en todos los tratamientos, con respecto a la biomasa total, varió de 9.88 a 13.1% en hoja; 1.83 a 4% tallo, 1.9 a 4.9% raíz, 0.8 a 1.31% estolón y de 77.6 a 83.6% en tubérculo. El tratamiento de fertilización con 250N-80P-300K mg L-1 obtuvo la mayor acumulación de biomasa total por planta, 63.54 g; para hoja, 6.78 g, tallo 2.36 g, estolón 0.5, raíz 1.2 g y tubérculos 52.56 g. Mientras el tratamiento que presentó el índice más alto de cosecha fue T2 (200N-30P-250K) con 0.83, sólo diferente a los tratamientos T7(100N; 130P; 350K) y T11(150N; 180P; 300K) con 0.77 y 0.78, respectivamente. El índice de cosecha no estuvo relacionado con el número de tubérculos por planta, pues los tratamientos con mayor número de estos fueron el T8 (200N-130P-250K) con 18.6 tubérculos y T12(150N-80P-400K) 18.2, con un índice de cosecha de 0.82, mientras el T3 con el mayor indice (0.83) solamente produjo 13.7 tubérculos por planta.

The main influential factor of biomass accumulations between male and female Populus cathayana seedlings was investigated from the point of factor analysis under drought stress. The results shows that biomass accumulations of seedlings under drought stress are mainly associated with stem dry mass (SDM), root dry mass (RDM), height growth (HG), basal diameter (BD), total leaf number (TLN) and other morphologic changes, and have little relation with intrinsic water use efficiency (WUE). There is sex differences in the mode of biomass accumulation between male and female plants. Biomass accumulation in female plants depends on morphologic changes, followed by hormonal regulation, and finally physiological progress. However, biomass accumulation in male plants depends on morphologic changes, followed by physiological progress, and finally hormonal regulation. Moreover, biomass accumulation in female plants on the morphologic aspects mainly depends on SDM, while is not relevant to TLN. However, male plants mainly depend on SDM, and have relationship with TLN. In sum, our study demonstrates that biomass accumulations in male and female P. cathayana seedlings under drought stress have different strategies.

The main influential factor of biomass accumulations between male and female \emph{Populus cathayana} seedlings is investigated from the point of factor analysis according to biomass of \emph{P. cathayana} seedlings under drought stress as well as related morphological, physiological, and biochemical indicators. The results shows that biomass accumulations in male and female plants under drought stress are mainly associated with stem dry mass (SDM), root dry mass (RDM), height growth (HG), basal diameter (BD), total leaf number (TLN) and other morphologic changes, and have little relation with intrinsic water use efficiency (WUE). There is sex differences in the mode of biomass accumulation between male and female plants. Biomass accumulation in female plants depends on morphologic changes, followed by hormonal regulation, and finally physiological progress. However, biomass accumulation in male plants depends on morphologic changes (similar to female plants), followed by physiological progress, and finally hormonal regulation. Moreover, biomass accumulation in female plants on the morphologic aspects mainly depends on SDM, while is not relevant to TLN. However, male plants mainly depend on SDM, and have relationship with TLN. In sum, our study demonstrates that biomass accumulations in male and female \emph{P. cathayana} seedlings under drought stress have different strategies.

Previous articleNext article No AccessNotes and CommentsIs Interspecific Variation in Relative Growth Rate Positively Correlated with Biomass Allocation to the Leaves?Hendrik Poorter, and Hans LambersHendrik Poorter Search for more articles by this author , and Hans Lambers Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The American Naturalist Volume 138, Number 5Nov., 1991 Published for The American Society of Naturalists Article DOIhttps://doi.org/10.1086/285282 Views: 5Total views on this site Citations: 24Citations are reported from Crossref Copyright 1991 The University of ChicagoPDF download Crossref reports the following articles citing this article:Gabriela Woźniak, Damian Chmura, Marcin K. Dyderski, Agnieszka Błońska, Andrzej M. Jagodziński How different is the forest on post-coal mine heap regarded as novel ecosystem?, Forest Ecology and Management 515 (Jul 2022): 120205.https://doi.org/10.1016/j.foreco.2022.120205Maria Amélia Martins-Loução, Teresa Dias, Cristina Cruz Integrating Ecological Principles for Addressing Plant Production Security and Move beyond the Dichotomy ‘Good or Bad’ for Nitrogen Inputs Choice, Agronomy 12, no.77 (Jul 2022): 1632.https://doi.org/10.3390/agronomy12071632Maria Pepe, Loretta Gratani, Maria Fiore Crescente, Giacomo Puglielli, Laura Varone Daily Temperature Effect on Seedling Growth Dynamic of Three Invasive Alien Species, Frontiers in Plant Science 13 (Mar 2022).https://doi.org/10.3389/fpls.2022.837449Prakash Bhattarai, Zhoutao Zheng, Kuber Prasad Bhatta, Yagya Prasad Adhikari, Yangjian Zhang Climate-Driven Plant Response and Resilience on the Tibetan Plateau in Space and Time: A Review, Plants 10, no.33 (Mar 2021): 480.https://doi.org/10.3390/plants10030480Vanessa Buzzard, Sean T. Michaletz, Ye Deng, Zhili He, Daliang Ning, Lina Shen, Qichao Tu, Joy D. Van Nostrand, James W. Voordeckers, Jianjun Wang, Michael D. Weiser, Michael Kaspari, Robert B. Waide, Jizhong Zhou, Brian J. Enquist Continental scale structuring of forest and soil diversity via functional traits, Nature Ecology & Evolution 3, no.99 (Aug 2019): 1298–1308.https://doi.org/10.1038/s41559-019-0954-7Sarathi M. Weraduwage, Marcelo L. Campos, Yuki Yoshida, Ian T. Major, Yong-Sig Kim, Sang-Jin Kim, Luciana Renna, Fransisca C. Anozie, Federica Brandizzi, Michael F. Thomashow, Gregg A. Howe, Thomas D. Sharkey Molecular Mechanisms Affecting Cell Wall Properties and Leaf Architecture, (Oct 2018): 209–253.https://doi.org/10.1007/978-3-319-93594-2_8Jianshuang Wu, Susanne Wurst, Xianzhou Zhang Plant functional trait diversity regulates the nonlinear response of productivity to regional climate change in Tibetan alpine grasslands, Scientific Reports 6, no.11 (Oct 2016).https://doi.org/10.1038/srep35649Vanessa Buzzard, Catherine M. Hulshof, Trevor Birt, Cyrille Violle, Brian J. Enquist, Markku Larjavaara Re‐growing a tropical dry forest: functional plant trait composition and community assembly during succession, Functional Ecology 30, no.66 (Oct 2015): 1006–1013.https://doi.org/10.1111/1365-2435.12579R. Milla, J. Morente-López, T. Peeters Limited evolutionary divergence of seedlings after the domestication of plant species, Plant Biology 17, no.11 (Jun 2014): 169–176.https://doi.org/10.1111/plb.12220Dianne B. J. 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Enquist On the Vegetative Biomass Partitioning of Seed Plant Leaves, Stems, and Roots. K. J. Niklas and B. J. Enquist, The American Naturalist 159, no.55 (Jul 2015): 482–497.https://doi.org/10.1086/339459M. A. Zavala, J. M. Espelta, Javier Retana Constraints and trade-offs in Mediterranean plant communities: The case of holm oak-Aleppo pine forests, The Botanical Review 66, no.11 (Jan 2000): 119–149.https://doi.org/10.1007/BF02857785 Roderick Hunt and J. H. C. 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Los elicitores son sustancias de diversas fuentes tanto inorgánicos como orgánicos que pueden inducir efectos fisiológicos y cambios como la activación de respuestas defensivas y la acumulación de fitoalexinas en el organismo al cual son aplicados, por lo cual, el objetivo de esta investigación fue conocer el efecto de la aplicación de dos elicitores de origen natural sobre el vigor de plantas y la calidad de frutos de tomate en condiciones de estrés biótico causado por Fusarium oxysporum f. sp. lycopersici (FOL). Los elicitores de origen natural (E1 y E2) se aplicaron a los 7, 15 y 56 ddt (días después del trasplante); la inoculación del FOL se realizó a los 19 ddt, usando una concentración de 1×106 esporas mL-1. El vigor en las plantas consistió en medir: la incidencia y severidad de la enfermedad, unidades SPAD, conductancia estomática durante el desarrollo de las plantas, altura, peso seco total y rendimiento; así como el pH, sólidos solubles, firmeza y el contenido de vitamina C en los frutos. La aplicación de los elicitores disminuyó la severidad de los síntomas de la enfermedad. El elicitor E2 incrementó la altura de las plantas tratadas, la acumulación de biomasa y evitó la reducción en el rendimiento, también disminuyo el contenido de sólidos solubles en los frutos. Se concluye que la aplicación de elicitores de origen natural provenientes de extractos de plantas tuvo un efecto positivo sobre el vigor de las plantas de tomate inoculadas con FOL al incrementar la altura y la acumulación de biomasa total, además de que se modificaron algunas variables de calidad del fruto.&#x0D; &#x0D;

Abstract. Githaiga MN, Kotut K, Kariuki F, Kairo JG. 2019. Structure and biomass accumulation of natural mangrove forest at Gazi Bay, Kenya. Bonorowo Wetlands 9: 18-32. The goal of this study was to determine the forest structure and estimate biomass accumulation above and below ground in the mangrove forest of Gazi Bay. The western, middle, and eastern forest blocks of the Gazi Bay mangrove forest were investigated for forest structure, whereas the western forest block was determined for biomass accumulation. To calculate below-ground biomass accumulation, in-growth cores of 80 cm long, 20 cm broad, and 60 cm deep were employed. Above-ground biomass accumulation was calculated using data on tree height and stem diameter at breast height (DBH-130). Leaf phenology was observed by tagging shoots. At the start, environmental variables were measured every four months for a year across four mangrove species zones. The linear regeneration sampling approach was used to determine the composition and distribution pattern of natural regeneration (LRS). Salinity revealed a strong negative connection with above-ground biomass accumulation among the soil environment characteristics studied. Sonneratia alba had the highest biomass accretion rate of 10.5 1.9 t ha-1 yr-1 among the four forest zones. Rhizophora mucronata (8.5 0.8 t ha-1 yr-1), Avicennia marina (5.2 1.8 t ha-1 yr-1), and Ceriops tagal (2.6 1.5 t ha-1 yr-1) were the next most abundant species. Above-ground and below-ground biomass accumulation differed significantly among zones (F (3, 8) = 5.42, p = 0.025) and (F (3, 8) = 16.03, p = 0 001), respectively. There was a significant difference in total biomass accumulation across zones (F (3, 8) =15.56, p = 0.001). For the entire forest, a root : shoot biomass accumulation ratio of 2 : 5 was calculated. This study's findings provide more accurate estimates of mangrove carbon capture and storage, which can be used in carbon credit discussions in the emerging carbon market.

Abstract: Cat's claw creeper, Macfadyena unguis‐cati, a major environmental weed in coastal and sub‐coastal areas of Queensland and New South Wales, Australia is a target for classical biological control. Host specificity of Hypocosmia pyrochroma Jones (Lep., Pyralidae), as a potential biological control agent was evaluated on the basis of no‐choice and choice larval feeding and survival, and adult oviposition preference tests, involving 38 plant species in 10 families. In no‐choice tests, larval feeding and development occurred only on cat's claw creeper. In choice tests, oviposition and larval development was evident only on cat's claw creeper. The results support the host‐specificity tests conducted in South Africa, and suggest that H. pyrochroma is a highly specific biological control agent that does not pose any risk to non‐target plants tested in Australia. This agent has been approved for field release by relevant regulatory authorities in Australia.

Accumulation of plant biomass (Mg ha−1) with calendar time (wk) occurs as a result of photosynthesis for green land-based plants. A corresponding accumulation of mineral elements (kg ha−1) such as nitrogen, phosphorus, and potassium occurs from the soil through plant roots. Field data from literature for the warm-season annual cotton (Gossypium hirsutum L.) are used in this analysis. The expanded growth model is used to describe accumulation of biomass and mineral elements with calendar time. The growth model predicts a simple linear relationship between biomass yield and the growth quantifier, which is confirmed with the data. The growth quantifier incorporates the unit processes of distribution of solar energy which drives biomass accumulation by photosynthesis, partitioning of biomass between light-gathering and structural components of the plants, and an aging function. A hyperbolic relationship between plant nutrient uptake and biomass yield is assumed, and is confirmed for the mineral elements nitrogen, phosphorus, and potassium. It is concluded that the rate limiting process in the system is biomass accumulation by photosynthesis and that nutrient accumulation occurs in virtual equilibrium with biomass accumulation. The expanded growth model describes field data from California and Alabama rather well. Furthermore, all model parameters were common for the two sites with the exception of the yield factor A which accounts for differences in soil types, environmental conditions, fertilizer levels, and plant population.