Universidade Federal de Mato Grosso

About: Universidade Federal de Mato Grosso is a education organization based out in Cuiabá, Brazil. It is known for research contribution in the topics: Population & Species richness. The organization has 7748 authors who have published 10181 publications receiving 89994 citations.

The side-effects of pesticides on the egg parasitoid Trichogramma cacoeciae Marchal (Hym., Trichogrammatidae), acute dose-response and persistence tests

Abstract: The side-effects of 21 pesticides were tested on the Hymenoptera egg parasitoid Trichogramma cacoeciae, using four different types of laboratory methods. The methods combined: (a) adult parasitoid exposure to fresh pesticide residue on glass plates – initial toxicity worse case to select harmless preparations, (b) direct spray of host eggs enclosing the parasitoid pupae (less susceptible life stage), (c) duration of harmful activity (persistence) on adults – select preparations that are less persistent and (d) dose-response exposures LD50 – to assess the risk margin. The results showed that the preparations (used at the highest recommended dose) greatly differed in their initial toxicity as well as in their persistence. The fungicide Topsin M® (thiophanat-methyl) and the herbicides Pyramin® (chloridazon), Butisan® S (metazachlor) and Banvel® 70 WG (dicamba) were harmless to T. cacoeciae. The insecticides Match® (lufenuron) and Admiral® (pyriproxifen), the fungicides Bavistin® (carbendazim), Aliette® (fosetyl) and Captan® 83 W (captan) as well as the herbicides Duplosan® 600 KV (mecoprop-p) and Focus® (cycloxydim) were slightly harmful. The fungicide Scala® (pyrimethanil) was moderately harmful. Telmion® (rape oil), Vertimec® (abamectin) and Scala were harmful in the initial toxicity test but only slightly persistent. These less persistent preparations are likely to have less impact on the natural enemy in the field. In the persistence test, Zolone Flow® (phosalon), Polo® (difenthiuron), Euparen® M (tolylfluanid), Dithane® M 45 (mancozeb), Kumulus® (sulphur) constantly reduced parasitism by between 90 and 100% and were rated as persistent. The direct spray of parasitized host eggs showed that Zolone Flow, Polo, Eupareum M, Dithane M 45, Scala and Touchdown® were harmless to the parasitoid pupae within the egg, that Telmion, Thiram® 80 WG and Kumulus were slightly harmful and Vertimec was moderately harmful. The dose-response test indicated a risk quotient (dose in g or ml product per ha/LD50 value) of spray drift for off-field parasitoids for the chemicals in the order of increasing risk as follows: Polo (1.33) followed by Thiram (3.62), Touchdown (7.54), Scala (10.39), Dithane M 45 (13.94), Telmion (27.04) and Zolone Flow (39.34).

Flagellate infections of Brazilian sand flies (Diptera: Psychodidae): isolation in vitro and biochemical identification of Endotrypanum and Leishmania

Abstract: Flagellate infections were found in 1,063 of 18,895 sand flies collected in the states of Amazonas, Para, Rondonia and Acre, Brazil. Infection rates were 13.4% (species group Shannoni); 7.5% (subgenus Nyssomyia); 6.7% (subgenus Lutzomyia series Cruciata); 0.5% (genus Psychodopygus) and 3.1% for other sand flies (various subgenera). Leishmania braziliensis guyanensis and L. mexicana amazonensis were isolated, respectively, from the known vectors, Lutzomyia umbratilis and L. flaviscutellata. Single stocks of L. braziliensis-like and L. mexicana-like organisms were isolated, respectively, from L. whitmani and L. yuilli. Thirty-eight flagellate stocks, isolated by direct culture from sand flies were characterized in detail by morphology in culture, behavior in hamsters and mice and by enzyme profiles. Sixteen stocks from Lutzomyia sp. (Shannoni group) were identified as Endotrypanum schaudinni; 8 stocks from Lutzomyia sp. (Shannoni group) were identified as Endotrypanum sp.; 7 stocks from Psychodopygus ayrozai and P. paraensis were identified as Leishmania sp. previously isolated from the armadillo, Dasypus novemcinctus; 2 stocks of Trypanosoma rangeli were isolated from recently fed Lutzomyia sp. (Shannoni group) sand flies; the remaining 5 stocks from L. umbratilis and L. yuilli could not be identified. Observations suggested that Shannoni group sand flies were the natural vectors of Endotrypanum. Leishmania sp. infections in the man-biting flies P. ayrozai and P. paraensis were restricted to the midgut and associated with recent bloodmeals. Unidentified flagellates in L. umbratilis and L. yuilli were distributed throughout the digestive tract with no trace of bloodmeals.

Reassessing the temporal evolution of orchids with new fossils and a Bayesian relaxed clock, with implications for the diversification of the rare South American genus Hoffmannseggella (Orchidaceae: Epidendroideae).

Abstract: The temporal origin and diversification of orchids (family Orchidaceae) has been subject to intense debate in the last decade. The description of the first reliable fossil in 2007 enabled a direct calibration of the orchid phylogeny, but little attention has been paid to the potential influence of dating methodology in obtaining reliable age estimates. Moreover, two new orchid fossils described in 2009 have not yet been incorporated in a molecular dating analysis. Here we compare the ages of major orchid clades estimated under two widely used methods, a Bayesian relaxed clock implemented in BEAST and Penalized Likelihood implemented in r8s. We then perform a new family-level analysis by integrating all 3 available fossils and using BEAST. To evaluate how the newly estimated ages may influence the evolutionary interpretation of a species-level phylogeny, we assess divergence times for the South American genus Hoffmannseggella (subfam. Epidendroideae), for which we present an almost complete phylogeny (40 out of 41 species sampled). Our results provide additional support that all extant orchids shared a most recent common ancestor in the Late Cretaceous (~77 million years ago, Ma). However, we estimate the crown age of the five orchid subfamilies to be generally (~1-8 Ma) younger than previously calculated under the Penalized Likelihood algorithm and using a single internal fossil calibration. The crown age of Hoffmannseggella is estimated here at ~11 Ma, some 3 Ma more recently than estimated under Penalized Likelihood. Contrary to recent suggestions that orchid diversification began in a period of global warming, our results place the onset of diversification of the largest orchid subfamilies (Orchidoideae and Epidendroideae) in a period of global cooling subsequent to the Early Eocene Climatic Optimum. The diversification of Hoffmannseggella appears even more correlated to late Tertiary climatic fluctuations than previously suggested. With the incorporation of new fossils in the orchid phylogeny and the use of a method that is arguably more adequate given the present data, our results represent the most up-to-date estimate of divergence times in orchids.