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Traditionally, chapattis are flatbreads made from atta (wholemeal Indian wheat flour). Non-atta chapattis have not been popular due to substandard product quality. To investigate what makes atta special for making chapattis, products were made using atta, Australian wholemeal wheat flour, gluten-free lupin flour, and a blend of lupin and wheat flours. Doughs were characterised by measuring strain-hardening and elastic recovery in compression and also bubble structures via 3-D X-ray micro-tomography. A method was developed to identify and separate bran, which appears as bubbles, in scans of doughs. 相似文献
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Andrés F. Sánchez-Restrepo Nadia L. Jiménez Viviana A. Confalonieri Luis A. Calcaterra 《国际虫害防治杂志》2019,65(3):244-257
AbstractLeaf-cutting ants (LCA) are considered one of the main herbivores and one of the most destructive pest insects of the Neotropics. Northeastern Argentina harbors the greatest species richness of these ants and in turn comprises the highest surface with forest plantations. Our aim was to establish which species of leaf-cutting ants are most commonly associated with forest plantations by analyzing their geographic distribution using published and unpublished species occurrence data. Also, estimate their potential areas of distribution along a latitudinal gradient that entirely encompasses northeastern Argentina using Ecological Niche Modeling. Only seven of the 20 species recorded were strongly associated with productive systems along the gradient, but only 2–3 species in each region could be considered high-risk species for forest plantations. High-risk species composition shows a turnover between regions. Our models show the potential distribution areas where LCA could become more abundant and dominant, and possibly causing a detrimental effect on the forest plantations in the studied region. We find that ecological niche models are useful tools to assess the environmental suitability of important LCA. 相似文献
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Bigi MF Torkomian VL de Groote ST Hebling MJ Bueno OC Pagnocca FC Fernandes JB Vieira PC da Silva MF 《Pest management science》2004,60(9):933-938
The focus of this study was the identification of compounds from plant extracts for use in crop protection. This paper reports on the toxic activity of fractions of leaf extracts of Ricinus communis L (Euphorbiaceae) and isolated active compounds in the leaf-cutting ant Atta sexdens rubropilosa Forel and its symbiotic fungus Leucoagaricus gongylophorus (Singer) M?ller. The main compounds responsible for activity against the fungus and ant in leaf extracts of R communis were found to be fatty acids for the former and ricinine for the ants. 相似文献
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BACKGROUND: Leaf‐cutting ants collect plant fresh material for the cultivation of their mutualistic fungus. Atta sexdens rubropilosa Forel (Hymenoptera: Formicidae) cause great economic losses through their foraging activity, mainly in agriculture. The main control method is the application of granulated toxic baits incorporated with an active ingredient (AI). The present goal is to evaluate the effect of caffeine on in vitro growth of the mutualistic fungus and on the survival of the leaf‐cutting ants, aiming to verify the potential toxicity of this secondary metabolite over these organisms. RESULTS: Three distinct patterns of fungal growth correlated with caffeine concentration were observed: (1) no effect (0.01% caffeine); (2) intermediate growth reduction (0.05% caffeine); (3) drastic growth reduction (0.10 and 0.50% caffeine). The highest caffeine concentration causes fungus death in the first week. As for insect survival, caffeine does not seem to exert any effect. The treatments with diet containing caffeine showed similar values of M50, irrespective of caffeine concentration. CONCLUSION: As caffeine was shown to reduce growth of the mutualistic fungus of Atta sexdens rubropilosa, but with no conclusive effect on insect survival, a hypothetical explanation for the selection of different Coffea species by this leaf‐cutting ant species might be associated with caffeine toxicity to the fungus. Copyright © 2011 Society of Chemical Industry 相似文献
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Leaf‐cutting ants are generally recognized as important pest species in Neotropical America. They are eusocial insects that exhibit social organization, foraging, fungus‐cultivation, hygiene and a complex nest structure, which render their management notoriously difficult. A lack of economic thresholds and sampling plans focused on the main pest species preclude the management of leaf‐cutting ants; such management would facilitate their control and lessen insecticide overuse, particularly the use of insecticidal baits. Recent restrictions on the use of synthetic compounds for such purposes impose additional challenges for the management of leaf‐cutting ants. Considerable effort has been exerted regarding these challenges, which are addressed herein, but which also remain challenges that are yet to be conquered. © 2013 Society of Chemical Industry 相似文献
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Victor SR Crisóstomo FR Bueno FC Pagnocca FC Fernandes JB Correa AG Bueno OC Hebling MJ Bacci Júnior M Vieira PC da Silva MF 《Pest management science》2001,57(7):603-608
The development of Leucoagaricus gongylophorus, the fungus cultured by the leaf-cutting ant Atta sexdens was inhibited in vitro by synthetic compounds containing the piperonyl group. In addition, worker ants that were fed daily on an artificial diet to which these compounds were added had a higher mortality rate than the controls. The inhibition of the fungal growth increased with the size of the carbon side chain ranging from C1 through C8 and decreasing thereafter. 1-(3,4-Methylenedioxybenzyloxy)octane (compound 5) was the most active compound and inhibited the fungal development by 80% at a concentration of 15 micrograms ml-1. With worker ants the toxic effects started with compound 5 and increased with the number of carbons in the side chain. Thus, for the same concentration (100 micrograms ml-1) the mortality rates observed after 8 days of diet ingestion were 82%, 66% and 42%, for 1-(3,4-methylenedioxybenzyloxy)decane, 1-(3,4-methylenedioxybenzyloxy)dodecane and compound 5, respectively, whereas with commercial piperonyl butoxide the mortality was 68%. The latter compound, which is known as a synergist insecticide, was as inhibitory to the symbiotic fungus as the synthetic compound 5. The possibility of controlling these insects in the future using compounds that can target simultaneously both organisms is discussed. 相似文献
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Studies assessing the characteristics of active ingredients (AIs) of toxic baits for leaf-cutting ants are still scarce, although
the need for a delayed action of these compounds on adult workers has been well accepted (mortality ≤15% at 24 h and ≥90%
at 21 days). Therefore, we determined the insecticidal action of two AIs used in commercial baits, diflubenzuron and dechlorane,
over time in workers, and discussed the control of colonies in relation to the existing literature. Dechlorane presented excellent
insecticidal activity with a delayed action at all concentrations tested, although its commercial use has been prohibited
due to its organochlorine nature. In contrast, diflubenzuron did not cause significant mortality or symptoms of intoxication,
indicating that the successful cases reported with the use of baits containing this AI were in fact due to an accidental contamination
with dechlorane. We comment about the ineffectiveness of diflubenzuron on alternative targets, i.e., young forms and the mutualistic
fungus, supporting the concept that the AI needs to a have a delayed action on adult workers. 相似文献
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Recent studies have shown an insecticidal effect of Tithonia diversifolia (Hemsl.) Gray (Asterales: Asteraceae) foliage on workers of Atta cephalotes L. and inhibitory effects of this plant on the growth of the symbiotic fungus Leucoagaricus gongylophorus (A. Müler) Singer. To evaluate the potential of T. diversifolia as a biological control treatment of this important pest, we assessed the effect of green manure (mulch) of this plant on natural nests of A. cephalotes, in Cali, Colombia. Three treatments were randomly assigned to 30 nests: 1) green mulch of T. diversifolia, 2) green mulch of Miconia sp., Ruiz & Pav. and 3) unmulched control. Every 2 wk for 6 mo, the surface of the nests was completely covered with leaves. Physical and chemical parameters of nest soil were assessed before the first and after the last application of the mulch. Ant foraging in T. diversifolia-treated nests decreased by 60% after the initial applications of the mulch, while nest surface area decreased by 40%. When the nests covered with T. diversifolia were opened, it was observed that the superficial fungus chambers had been relocated at a greater depth. In addition, microbial activity and soil pH increased by 84% and 12%, respectively, in nests covered with plant residues. In conclusion, the continued use of T. diversifolia mulch reduces foraging activity and negatively affects the internal conditions of the colonies, thereby inducing the ants to relocate the fungus chambers within the nests. 相似文献
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Britta Denise HARDESTY 《Integrative zoology》2011,6(3):222-226
Seed dispersal and subsequent recruitment is the template on which forest regeneration takes place. Hence, considering the scale over which ecological processes occur is key for understanding the overall impact of various dispersal agents. To explore leafcutter ant (Atta colombica) dispersal effectiveness in space and time, seed movement and subsequent recruitment of a large‐seeded predominately vertebrate‐dispersed tree, Simarouba amara (Aubl. Simaroubaceae), was investigated on Barro Colorado Island, Panama. At each of 218 reproductive‐sized adults (≥20 cm diameter at breast height), presence or absence of a leafcutter ant colony was noted, with extensive checks for Atta activity taking place at or in close proximity to seed and seedling transects, which extended 4 cardinal directions for 30 m from each reproductive female tree (n= 74). Only at 2 S. amara trees were nests observed, and in these areas a dense S. amara seedling carpet was observed. Although nearby nest and dump sites might increase local S. amara recruitment in the short term, mortality at these sites is complete or nearly so. Hence, the seed dispersal effectiveness by leafcutter ants appears to be ephemeral and likely contributes inconsequentially to the long‐term recruitment and distribution patterns of the species. This finding highlights the importance of evaluating disperser effectiveness at ecologically relevant spatiotemporal scales. 相似文献
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