Lysiloma Latisiliquum Research Articles

Diversity, composition, and structure of wood species of tropical dry forest in Lerma, Campeche

The objective of this study was to describe the diversity, composition, and structure of the woody vegetation in a section of LDF in Lerma, Campeche. Between August and September 2018, 10 plots of 10 × 10 m2 (1 000 m2 in total) were delimited, measuring all woody individuals with diameter at breast height (DBH = 1.30 cm). The structure of the site was described based on the relative values of density, frequency, and dominance (IVI), as well as the distribution of diameter classes. Diversity was estimated with the Shannon-Wiener index (H'), while equity was measured by the Pielou index. 40 woody species were recorded, belonging to 35 genera and 19 families. The H' index had a value of 2.92, and the Pielou index was 0.79, the density was 8 950 ind ha-1. Gymnopodium floribundum (204 individuals) and Lonchocarpus xuul (129) were the most abundant species. Bursera simaruba and Lysiloma latisiliquum showed higher diameter values (36 and 28.6 cm DBH, respectively). The families Rubiaceae (eight species), Fabaceae (five species), Ebenaceae and Polygonaceae (three species each) were the most representative. The species with the highest IVI were Gymnopodium floribundum (48.24%), Lonchocarpus xuul (29.12%), Bursera simaruba (26.11%) and Lysiloma latisiliquum (24.98%), these species being the most important in the structure of the LDF in the site. The distribution of the diameter classes suggests that the section of the LDF in Lerma Campeche is in an adequate state of regeneration.

Unravelling genetic diversity of whitefly species on different host plants from New Delhi

Aim: This study investigates the genetic diversity and distribution of different species of whiteflies on 20 host plants vegetables (cucumber, summer squash, pumpkin, tomato, brinjal, okra), field crops (sunflower, lettuce, field bean, lobia), commercial crops (cotton, tobacco), ornamentals (chrysanthemum, bellflower, marigold), fruit crops (lemon), trees (mulberry, wild tamarind, ficus), and others (wild brinjal) in New Delhi. Methodology: Genetic diversity was assessed through mitochondrial cytochrome oxidase-I gene-based molecular markers. Results: Phylogenetic analysis revealed that whitefly Bemisia tabaci was the most prevalent pest species across the crops reported in this study. The other whitefly species, viz., Dialeurodes sp., Singhiella simplex, Aleuroclava sp., Tetraleurodes acaciae, Trialeurodes vapororium, and Aleurodicus floccissimus were reported as pests of different horticultural crops. Interpretation: Genetic diversity of B. tabaci revealed that the genetic groups Asia II-1 and Asia II-7 were most prevalent, while Asia I was the minor one. Understanding the species composition and genetic diversity of whiteflies will help in devising appropriate control strategies. Key words: Hosts, Molecular markers, mtCOI, New Delhi, Phylogenetic analysis, Whitefly diversity

The in vitro rumen exsheathment test for studying the effect of plant extracts on the exsheathment of Haemonchus contortus infective larvae

This study applied the in vitro rumen exsheathment test (IVRET) to evaluate the exsheathment kinetics of Haemonchus contortus infective larvae (L3) incubated in ruminal liquor (RL) containing acetone:water extracts of Acacia pennatula (AP), Gymnopodium floribundum (GF), Havardia albicans (HA) or Lysiloma latisiliquum (LL). The role of polyphenols in the biological activity of the evaluated extracts was also determined. Larvae were incubated in RL either alone or added with a different plant extract (AP, GF, HA, or LL) at 1200 μg/mL. Polyethylene glycol (PEG) was added to block polyphenols in each treatment (RL+PEG, AP+PEG, GF+PEG, HA+PEG, and LL+PEG). After incubation times of 0, 1, 3, 6, 9, and 24 h, the exsheathment process was stopped to count the number of ensheathed and exsheathed L3. A Log-Logistic model was used to determine the L3 exsheathment kinetics in the different RL treatments. The inflection point of the respective kinetic curves, which indicates the time to reach 50 % exsheathed L3 (T50), was the only parameter that differed when comparing the exsheathment models (99 % probability of difference). The T50 values obtained for GF, HA, and LL treatments (T50 = 7.11 – 7.58 h) were higher in comparison to the T50 of RL (5.72 h) (≥ 70 % probability of difference). The L3 incubated in RL added with GF, HA, and LL extracts delayed their exsheathment at 3 and 6 h of incubation (28.71 – 48.06 % exsheathment reduction) compared to the RL treatment. The T50 value for AP, AP+PEG, GF+PEG, HA+PEG, and LL+PEG were similar to RL and RL+PEG (T50 = 5.34 – 6.97 h). In conclusion, the IVRET can be used to identify plants with the potential to delay the exsheathment of H. contortus L3 in the ruminal liquor. The acetone:water extracts of G. floribundum, H. albicans, and L. latisiliquum delayed the T50 of H. contortus exsheathment, which was evident at 3 and 6 h of incubation in ruminal liquor. The observed exsheathment delay was attributed to the polyphenol content of the extracts.

Umbonia crassicornis (Amyot & Serville, 1843) (Hemiptera: Membracidae) nymphal aggregation size and density affect host plant and treehopper growth

There was a significant negative relationship between the density of Umbonia crassicornis (Amyot & Serville, 1843) aggregations and the average length of the newest growth on its host plant, Lysiloma latisiliquum Benth. (Fabaceae). There was also a significant negative relationship between aggregation size and the dry mass of the teneral adults of both sexes. Teneral female U. crassicornis were significantly longer and had a significantly greater dry mass than their male siblings. I suggest that feeding by treehopper nymphs reduces the nutrient pool of the host plant, resulting in reduced plant and treehopper growth.

Foliage of Tropical Trees and Shrubs and Their Secondary Metabolites Modify In Vitro Ruminal Fermentation, Methane and Gas Production without a Tight Correlation with the Microbiota.

Simple SummaryRuminants produce methane, a potent greenhouse gas, as a byproduct of microbial activity during ruminal fermentation. To lessen greenhouse gases emissions, it is necessary to evaluate methane-reducing feeding alternatives for ruminants, such as the use of tropical trees and shrubs. The secondary metabolites produced by these plants have been shown to reduce ruminal methane emissions. Here, we evaluated the effect of the foliage of eleven tropical trees and shrubs edible for cattle in ruminal fermentation, methane production and microbiota in an in vitro assay. The content of condensed tannins and saponins in the foliage was variable between the species of plants. We observed a reduction in methane production and changes in microbial populations depending on the species of tree or shrub. Additionally, condensed tannins reduced methane production. The inclusion of the foliage of tropical trees and shrubs in the diet of ruminants may be a step towards diminishing greenhouses gases emissions, and therefore reducing the contribution to global warming from cattle production.Ruminants, mainly cattle, contribute to greenhouse gases (GHG) emissions as methane (CH4) is produced by ruminal fermentation. Hence, various anti-methanogenic feed strategies have been studied, including the use of plants with secondary metabolites. This study evaluated in vitro ruminal fermentation metrics, microbial composition by digital droplet PCR (ddPCR) and the CH4 production of the foliage of several tropical trees and shrubs: Leucaena leucocephala, Moringa oleifera, Albizia lebbeck, Enterolobium cyclocarpum, Piscidia piscipula, Brosimum alicastrum, Lysiloma latisiliquum, Guazuma ulmifolia, Cnidoscolus aconitifolius, Gliricidia sepium and Bursera simaruba, using Cynodon plectostachyus grass as control. The results showed a wide variation in the chemical composition of the foliage, as well as in the ruminal microbiota. The crude protein (CP) content ranged from 11 to 25%, whereas the content of condensed tannins (CT) and saponins (S) was from 0.02 to 7%, and 3.2 to 6.6%, respectively. The greatest dry matter degradability (DMD) after 72 h was 69% and the least 35%, the latter coinciding with the least gas production (GP). A negative correlation was found between the CT and CH4 production, also between protozoa and fungi with the SGMT group of archaea. We concluded that the foliage of some tropical trees and shrubs has a high nutritional value and the potential to decrease CH4 production due to its CT content.

On the basic chemical composition of selected biomass types from four regions of Mexico, for bioenergetic purposes

The chemical composition of hardwoods sawdust and citrus residues from four states of the Mexican Republic (Quintana Roo, Durango, Veracruz, and Sonora) were determined. The results ranged as follows: total extractives from 8.2% (Quercus spp.) to 35.0% (lime leaves), holocellulose from 45.4% (lime leaves) to 70.6% (Lysiloma latisiliquum), lignin from 3.9% (lemon peels) at 25.4% (Caesalpinia platyloba), ash from 0.4% (orange branches) to 6.3% (lemon peels), pH from 5.1 (Swartzia cubensis) to 7.3 (orange branches), and calorific value of 19.8 MJ/kg (Lysiloma latisiliquum and Quercus spp.) to 21.7 MJ/kg (Olneya tesota). With the exception of the oak samples, in all the biomass samples the extractives content is relatively high (10.1% for Lysiloma latisiliquum to 35% for Persian lime leaves), and could represent a potential for future study and applications in the field of antioxidants. Due to the chemical properties and calorific value, the biomass samples studied present potential for local use as densified biofuels (pellets or briquettes).

Restoring commercial timber species through silvicultural patch clear-cuts and natural regeneration in Mexico’s Maya Forest: Composition and growth 11 years after three treatments

The natural regeneration of 27 commercial and potentially commercial timber species was studied on experimental clearings in managed forests on three ‘ejidos’ and one private property in Quintana Roo, Mexico. Eight ½ ha clear-cuts had been created 11 years earlier using each of three different clearing treatments: slashing, felling and leaving (felled); slashing, felling and burning (burned); and machine-clearing. More than 6000 trees of 108 species were identified and measured on six 49 m2 quadrats on each of the experimental clear-cuts, and on the same number and size of quadrats in the neighboring forest. The Basal Area (BA) of different commercial timber groups differed among treatments. After machine-clearing, 47% of the BA was made up of currently commercial timber species, 39% the more valuable decorative hardwoods and 8% lesser value softwoods; on burned treatments, 40% of the BA was currently commercial timber species, 29% decorative hardwoods and 11% softwoods. On both these treatments Lysiloma latisiliquum, one of the most valuable hardwoods, accounted for more than 25% of the BA. On felled treatments, 29% of the BA was commercial timber species; 6% decorative hardwoods, 22% softwoods and 1% precious woods (Swietenia macrophylla). On controls, currently commercial species accounted for 27% of the BA, of which 21% was decorative hardwoods, 5% softwoods and 1% precious woods. The decorative hardwood species L. latisiliquum did not occur on control plots and was rare on felled plots. Depending on the treatment, palms and non-commercial species accounted for 31% to 52% of the BA, and ‘potentially commercial’ species or ‘other species of commercial interest’ accounted for 15% to 41% of the BA. On felled clearings, 30% of individuals were sprouts, as compared to 19% on burned clearings and 11% after machine-clearing. The largest trees on burned and machine-made clearings had grown approximately 1 cm in diameter year−1. Opening small clearings within the forest matrix using the same slash and burn treatments that local farmers use to open their agricultural fields, or machines like bulldozers, stimulated the natural regeneration of commercially valuable decorative hardwood species, of which 75% have been classified as shade-intolerant. These do not regenerate satisfactorily under the current regime of selective logging. The silvicultural management system for the Maya Forest must include patch clear-cuts and the conservation of seed trees and their pollinators and dispersors to sustain the commercial timber value of the forest, and its biodiversity.

Variation in Results of Three Biology‐Focused Search Engines: A Case Study Using North American Tree Species

Variation in Results of Three Biology‐Focused Search Engines: A Case Study Using North American Tree Species

Modelos altura-diámetro con efectos mixtos para Lysiloma latisiliquum (L) Benth. en Quintana Roo, México

El objetivo fue determinar el modelo alométrico con efectos mixtos que mejor describe la relación altura total-diámetro normal (A-d) para árboles de Lysiloma latisiliquum en Quintana Roo, México. Con 2214 pares de datos A-d obtenidos del Inventario Nacional Forestal y de Suelos (2004-2009), se calculó el índice de esbeltez (IE: A/d) y se ajustaron seis modelos locales; posterior a la elección del mejor modelo se incluyeron bajo el enfoque de modelos de efectos mixtos las covariables de conglomerado, diámetro de copa (dc), altura de fuste limpio (Af), municipio (M), tipo vegetación primaria (Vp) y altitud, para mejorar el ajuste. El IE disminuye a medida que aumentan las dimensiones del arbolado. El modelo de Hossfeld (1822) con la inclusión de la covariable de conglomerado en el parámetro resulto ser el mejor para describir la relación A-d, ya que explica más de 70% de la variabilidad muestral y tiene un sesgo de 0.00013 m. Además, al contrastar las estimaciones con datos de una muestra independiente, no se observaron diferencias significativas a un nivel de 99% de confiabilidad. La inserción de las diferentes condiciones ambientales y de crecimiento, modifican la relación alométrica A-d en Lysiloma latisiliquum en los bosques tropicales de Quintana Roo, México y los modelos mixtos mostraron ser una opción de mejora estadística y precisión en la estimación.

Estructura y composición florística de la selva mediana subcaducifolia en Hobomó, Campeche, Campeche, México

Se estudió florísticamente la composición y estructura de la selva mediana subcaducifolia en dos sitios del área de Hobomó, Campeche, México. Se seleccionaron dos sitios, en cada uno se delimitaron 10 parcelas de 10 m2 × 10 m2 (1000 m2) y se midieron todos los individuos de ≥ 1 cm de diámetro. El análisis estructural de la selva mediana subcaducifolia se basó en los valores de importancia de las especies. La diversidad se estimó con el índice de Shannon-Wiener (H’). Mediante observaciones y recolectas se detectaron 79 especies de plantas vasculares, pertenecientes a 67 géneros y 30 familias. Las familias más diversas fueron Fabaceae y Rubiaceae en ambos sitios. El género más diverso fue Diospyros, seguido de Coccoloba y Guettarda. La diversidad de especies leñosas en los sitios 1 y 2 fue de 3.68 y 3.59, sus valores de equidad (uniformidad) de acuerdo con el índice de Pielou fueron de 0.88 y 0.87 y su densidad fue de 6610 individuos por hectárea (ind/ha) y 8670 ind/ha, respectivamente. Las tres especies con mayor densidad fueron Malpighia glabra, Guettarda combsii y Lonchocarpus xuul en el sitio 1 y Machaonia lindeniana, Coccoloba cozumelensis y Malpighia glabra en el sitio 2. Los valores más altos de los índices de valor de importancia fueron Bursera simaruba, Lonchocarpus xuul, Guettarda combsii, Platymiscium yucatanum y Malpighia glabra en el sitio 1 y Lysiloma latisiliquum, Bursera simaruba, Vitex gaumeri, Lonchocarpus xuul y Machaonia lindeniana en el sitio 2. Estas especies son las más importantes en la estructura y fisonomía de la comunidad vegetal. Se puede concluir que la riqueza de especies arbóreas de los dos sitios estudiados es similar (sitio 1con 63 spp. y sitio 2 con 62 spp.). La escasez o abundancia de las especies está relacionada con la actividad humana (extracción de madera), la cual afecta la estructura y composición florística.

Wood anatomical and topochemical analyses to characterize juvenile and adult wood of lesser-known species from Central America (Mexico)

ABSTRACT Anatomical and subcellular characteristics of juvenile and adult wood of seven species (Manilkara zapota (L.) P. Royen, Platymiscium yucatanum Standl., Lonchocarpus castilloi Standl., Roseodendron donnell-smithii (Rose) Miranda, Terminalia buceras (L.) Wright, Tabebuia rosea (Bertol.) DC., Lysiloma latisiliquum (L.) Benth. from Mexico, including a histometric evaluation, were investigated by light microscopy with a digitized image analysis system and by X-ray diffractometry using the SilviScan® system. The topochemical distribution of lignin and phenolic deposits in the tissue was studied by means of cellular UV-microspectrophotometry (UMSP). Extractive contents (acetone/water and water) were determined gravimetrically. The results of the structural and topochemical analyses were compared with the interrelations of certain anatomical and subcellular structures as well as the topochemical composition with regard to the physical and mechanical properties of the timbers investigated. The objective was to provide a detailed cellular and subcellular description of the heartwood of seven lesser-known timbers from Central America. All examined tree species show significant differences between juvenile and adult heartwood. For individual species, however, the differences vary greatly and have to be individually assessed in addition to general trends observed for all studied species. It has been shown that vessel size, fibre length, size of fibre lumina, and height and width of rays, as well as the content of extractives and topochemical composition of the cell walls, are suitable indicators for the differentiation of the two heartwood types. The results also contribute to a better understanding of the wood properties of the investigated timbers in relation to their utilization and added value increase.

Habitat generalization of a predatory ladybird, Harmonia yedoensis (Coleoptera: Coccinellidae), in an allopatric area with respect to its sibling species Harmonia axyridis

ABSTRACTIn central Japan, Harmonia yedoensis is a specialist ladybird that is confined to pine tree habitats, whereas its sibling species Harmonia axyridis is a generalist that feeds on a wide range of aphid species in nature. Interestingly, H. axyridis is not distributed in the Ryukyu Archipelago, southern Japan. We hypothesized that the ecological niche of H. yedoensis should be wider in the Ryukyu Archipelago, where its competitor species in central Japan, H. axyridis, is absent. We undertook fieldwork and a survey of published works to examine habitat utilization by H. yedoensis in the Ryukyu Archipelago. We found that H. yedoensis adults in the Ryukyu Archipelago visited several kinds of deciduous trees, including wild tamarind, Chinese hibiscus, Taiwan cherry and Malayan banyan, as well as pine trees. These observations suggest that habitat generalization has occurred in H. yedoensis in the Ryukyu Archipelago, where it does not compete with H. axyridis.

Crecimiento en diámetro de tres especies arbóreas en una selva secundaria de Quintana Roo, México

Bursera simaruba, Lysiloma latisiliquum y Piscidia piscipula son tres especies de las selvas subperennifolias de Quintana Roo que son valoradas favorablemente por su madera. Para seguir incentivando su aprovechamiento y conservación, así como su conocimiento ecológico, se requiere determinar la tasa de crecimiento anual y los factores que lo modulan. En el presente estudio se midió el crecimiento en diámetro de Bursera simaruba, Lysiloma latisiliquum y Piscidia piscipula, en selvas secundarias medianas subperennifolias del ejido Andrés Quintana Roo, Quintana Roo. Setenta y tres árboles fueron categorizados en cinco intervalos de diámetro y medidos cada dos meses, empleando bandas dendrométricas; el estudio abarcó desde enero de 2011 hasta mayo de 2012. Los incrementos se correlacionaron con la precipitación, temperatura promedio del aire y humedad relativa locales. Los incrementos se ajustaron a un modelo polinómico de tercer orden. L. latisiliquum presentó la tasa de crecimiento promedio anual más alta (0.18 cm), seguida por P. piscipula (0.10 cm) y por B. simaruba (0.06 cm). Las categorías diamétricas de las tres especies presentaron diferencias significativas en sus incrementos; las de 20 cm, de forma general, crecieron más que las restantes. Los incrementos se correlacionaron de forma significativa (p ≤ 0.01) con la temperatura en las tres especies; la precipitación y la humedad relativa no tuvieron una influencia marcada en el engrosamiento del fuste. La presente investigación demostró tres patrones distintos de crecimiento, distinguiendo a la temperatura como un factor de influencia en el aumento del diámetro.

Crecimiento y regeneración avanzada de Lysiloma latisiliquum (L.) Benth. en una selva de Quintana Roo


 
 
 Aunque muchos árboles tropicales se extraen con fines comerciales, son escasas las investigaciones que han abordado el estudio de su regeneración, tasas de crecimiento y las técnicas sustentables para su aprovechamiento. La carencia de este tipo de información representa una de las mayores debilidades de los programas de manejo forestal, en las regiones tropicales de méxico. Lo anterior se refleja, por ejemplo, en que la caoba (Swietenia macrophylla) y el cedro (Cedrela odorata) están cada vez menos disponibles en las selvas de Quintana roo. un efecto secundario de la disminución del volumen del cedro y la caoba es el incremento del número de las especies susceptibles de aprovecharse, y los volúmenes que de ellas se cosechan; tal es el caso del tzalam (Lysiloma latisiliquum), por lo que el objetivo del presente estudio fue contribuir al conocimiento sobre el crecimiento y la regeneración del tzalam, mediante la evaluación de 74 árboles entre 2002 y 2008 (en una selva sujeta a manejo comercial). se obtuvo una tasa de crecimiento anual de 0.41 cm y la ausencia de individuos con daP entre 2 y 10 cm, en 176 sitios de 30 m2. del total de ejemplares muestreados 84% se localizaron en suelo negro, que representa solamente 5% de los suelos de la selva estudiada. el futuro comercial sustentable del tzalam está muy amenazado, por la falta de plantas con daP de 2 y 10 cm.
 
 

EMERGENCIA DE PLÁNTULAS DE ESPECIES MADERABLES NATIVAS DE LA PENÍNSULA DE YUCATÁN


 
 
 La biodiversidad regional en la Península de Yucatán registra especies arbóreas nativas con potencial para ser usadas en la reforestación; sin embargo, su aprovechamiento requiere el estudio de sus características ecológicas, de ahí que la presente investigación se enfoque en la emergencia de plántulas de taxa maderables procedentes de dicha zona en vivero y bajo diferentes grados de sombra (0, 35, 60 y 90%); así como a la emergencia y supervivencia a partir de la siembra directa de semillas en lomeríos de la misma región. Para ello, se realizó la evaluación del cedro (Cedrela odorata), chakté (Caesalpinia mollis), ciricote (Cordia dodecandra), ja’abín (Piscidia piscipula), tzalam (Lysiloma latisiliquum) y granadillo (Platymiscium yucatanum). En vivero, C. mollis mostró diferencias significativas (p = 0.006), ya que obtuvo la mayor emergencia (53 y 49%) en los tratamientos de 0 y 35% de sombra; mientras que, en campo la consiguió en la posición alta de los lomeríos (p = 0.015, 1.9%); en contraste con P. piscipula (p = 0.005) que se originó en la baja (14.3%). Por otra parte, altos niveles de sombra (60 y 90%) redujeron los días necesarios para alcanzar 95% de plántulas emergidas en C. odorata, la cual presentó una supervivencia más alta (73.5%) en la posición elevada (p = 0.001) de los lomeríos, a diferencia de C. dodecandra (84.2%) que lo hizo en la inferior (p = 0.02). Los resultados expresan que el porcentaje de sombra influye poco en el tiempo de emergencia total de las plántulas y que los taxa estudiados difieren en sus preferencias por las posiciones en el paisaje.
 
 

Chemical composition and thermal properties of tropical wood from the Yucatán dry forests

Six different species of dry forest trees were collected, and their chemical compositions and thermal properties were determined. Three of the six species (Senegalia gaumeri, Havardia albicans, and Lysiloma latisiliquum) were chosen due to their high preference as firewood in local communities, while the remaining three species (Croton glabellus, Lonchocarpus yucatanensis, and Neomillspaughia emarginata) were chosen because of their abundance at the sampling site. The chemical compositions were consistent with the composition of tropical woods reported in previous literature, with an ash content of 4.8% to 6.8% and total extractible content in the range of 15.4% to 28.5%. The lignin content was in the range of 17.6% to 24.0%, while the range of holocellulose was 53.9% to 63.0%. The calculation of the calorific values was performed using the elemental analyses, and values ranging between 16.2 and 18.5 MJ/kg were obtained. The fuel value index (FVI) values for the samples indicated that S. gaumeri and L. yucatanensis were the best species for fuelwood given their high densities and relatively high calorific values. The kinetics of pyrolysis showed a higher level of reactivity for H. albicans and L. yucatanensis compared to the other species studied.

Ultrastructural study of adult Haemonchus contortus exposed to polyphenol-rich materials under in vivo conditions in goats.

This study assessed the ultrastructural changes caused in adult Haemonchus contortus obtained from goats fed fodder based on polyphenol-rich plants Lysiloma latisiliquum or Onobrychis viciifolia or from goats drenched with quebracho extract, Schinopsis spp. The H. contortus were obtained from artificially infected goats used as models to investigate the anthelmintic effect of feeding or drenching with the polyphenol-rich materials. Nematode populations were exposed to polyphenol-rich plant materials by feeding host goats for 8 consecutive days (D28 to D35 post-infection) with (a) L. latisiliquum fodder at 800 g fresh basis/day, (b) O. viciifolia fodder offered ad libitum, and (c) drenched with a solution containing quebracho extract (90 g/day). Meanwhile, control H. contortus were obtained from goats fed polyphenol-free diets. The H. contortus specimens were recovered from the goats on D36 post-infection, and transmission electron microscopy (TEM) was used to identify ultrastructural changes. In vivo exposure to different polyphenol-rich plant materials caused vacuolization of the nematodes’ intestinal, muscular and hypodermal cells. These alterations represent the first evidence of cell damage caused in H. contortus when hosts were fed or drenched with polyphenol-rich materials. Ultrastructural changes affecting several types of cells could explain modifications in worm motility and nutrition, eventually affecting H. contortus reproductive success. This study contributes to our understanding of the mechanisms of action of polyphenol-rich plants against H. contortus when given as nutraceuticals to goats.

An in vitro approach to evaluate the nutraceutical value of plant foliage against Haemonchus contortus.

Nutraceutical plants provide nutrients for the animal as well as secondary compounds that can affect the biology and survival of gastrointestinal nematodes (GIN). Current screening of nutraceutical plants is based on in vitro evidence of anthelmintic (AH) activity against different life stages of GIN, but nutritional information is omitted or scarce. This study proposes an integral in vitro screening protocol to identify the nutraceutical value of the foliage from plant species consumed by small ruminants, using Haemonchus contortus as a biological model. The leaves from Acacia collinsii, A. pennatula, Bunchosia swartziana, Gymnopodium floribundum, Havardia albicans, Leucaena leucocephala, Lysiloma latisiliquum, Mimosa bahamensis, Piscidia piscipula, and Senegalia gaumeri were evaluated for their chemical composition and in vitro digestibility. Acetone:water extracts (70:30) from leaves of each plant were evaluated using the egg hatch assay and larval exsheathment inhibition assay. Respective effective concentrations 50% (EC50) were determined for each assay. The ten plant species showed good nutritional value for ruminants, including crude protein (> 10%), metabolizable energy (> 2.9MJ/kg DM), and varied CT content (from 1.0 to 37.6%). The best AH activity against H. contortus eggs (EC50 = 401.8μg/mL) and L3 (EC50 = 83.1μg/mL) was observed for S. gaumeri extract. Although all the plant species showed in vitro nutraceutical potential, the leaves of S. gaumeri had the best values. The proposed in vitro protocol showed to be useful for the integral assessment of the nutraceutical potential of different plant species as it included the nutritional value and the AH activity against eggs and L3 in the selected plant species.

Vibrations guide thornbug treehoppers in pursuit of love

Cunningly disguised as thorns to avoid the unwanted attention of predators, thornbug treehoppers (Umbonia crassicornis) lead a sedentary existence. Sucking sap from the shrubs that they inhabit, the insects grow up in large family clusters until the youngsters strike out to find a mate. ‘Males fly from shrub to shrub, producing vibratory courtship signals, pausing to listen, then flying on to the next shrub if they receive no reply from a female’, says Jeremy Gibson, from the University of Strathclyde, UK. However, after homing in on an amorous female's shrub, the pressure is on to locate her as female thornbug treehoppers mate only once with the first male to arrive. Embarking on a duet in a bid to become united, the would-be lovers shiver their abdomens and the vibrations are carried down their legs and into the plant. However, Gibson and his graduate advisor Rex Cocroft, from the University of Missouri, USA, were unsure how thornbug treehopper males interpret the responses of their inamoratas in the pursuit of love.Arranging thornbug treehopper blind dates on young false tamarind trees (Lysiloma latisiliquum), Gibson recorded the vibrations generated by the duetting insects as the vibrations travelled through the shrub while filming the male's progress toward his intended. Then Gibson abducted the male, tricking the female into continuing her serenade while measuring the minute vibrations that she generated and the motion of the plant stem at the locations where the male had paused, to build a picture of the vibration features that had guided him.At the outset of each search, Gibson and Cocroft found that the males covered longer distances (up to 34 cm) before pausing for periods of 1.3–14.2 s as they vibrated their abdomens and then waited to feel the females’ responses before going on their way again. The male pursuers also located the objects of their affection more speedily and accurately when the females were located high in the tree, taking more wrong turns when lower down on the trunk. In addition, the males were able to determine the direction from which the vibrations approached – by sensing whether the vibration arrived at the front or rear legs first – and their accuracy improved when the vibrations travelled more slowly through the thinner twigs and as the vibrations became stronger when the male neared the female.It was also clear that the vibrations generated by the females became increasingly distorted the further they travelled through the shrub to reach the expectant males, prompting admirers to travel further between check points in order to improve their chances of making the right choice when next they paused. And sometimes the males continued walking even while serenading, pausing only to pay attention to the female's responses, possibly allowing the male to speed up his search in a bid to reach his lady love ahead of competing suitors.However, Gibson and Cocroft point out that the challenges facing vibration-guided amorous male thornbug treehoppers are likely to be even more testing in the rowdy real world – where the insects must also contend with buffeting wind, rain and the cacophony of competitors and predators – and the scientists are keen to learn more about the sensory strategies that the insects employ to ensure success.

Is there a negative association between the content of condensed tannins, total phenols, and total tannins of tropical plant extracts and in vitro anthelmintic activity against Haemonchus contortus eggs?

In vitro studies using plant extracts suggest a relationship between their polyphenol contents and their anthelmintic (AH) activity against Haemonchus contortus. High polyphenol content appears to increase the efficacy of plant extracts against H. contortus as assessed by the larval exsheathment inhibition assay (LEIA) while appearing to reduce the AH efficacy measured using the egg hatch assay (EHA). In addition, some plants lack AH activity. Therefore, the present study investigated the relationship between the contents of condensed tannins (CT), total phenols (TP), and total tannins (TT) in methanol:water extracts (70:30) obtained from ten tropical plant species consumed by small ruminants as well as their AH activity against H. contortus evaluated by LEIA and EHA. Extracts of Acacia collinsii, Lysiloma latisiliquum, Havardia albicans, Senegalia gaumeri, Mimosa bahamensis, Piscidia piscipula, Acacia pennatula, Gymnopodium floribundum, Leucaena leucocephala, and Bunchosia swartziana were examined. Positive correlations were found between the effective concentration 50% (EC50) (EHA) of extracts and their CT (r=0.6809, P<0.05, n=10) and TP (r=0.9152, P<0.05, n=10) content, suggesting that their concentration negatively affected AH activity against eggs. Based on the LEIA, there was no significant association between the EC50 and the CT, TP, or TT of all extracts evaluated. Thus, if sheep and goats consume a complex feed mixture with high amounts of CT, TP, and TT, it might be difficult to observe an AH effect against H. contortus egg hatching. However, the AH effect upon L3 establishment might be feasible.