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991.
Thiago Alves Magalhães Denis Coelho de Oliveira Aline Yasko Marinho Suzuki Rosy Mary dos Santos Isaias 《Protoplasma》2014,251(4):747-753
Cell redifferentiation, division, and elongation are recurrent processes, which occur during gall development, and are dependent on the cellulose microfibrils reorientation. We hypothesized that changes in the microfibrils orientation from non-galled tissues to galled ones occur and determine the final gall shape. This determination is caused by a new tissue zonation, its hyperplasia, and relative cell hypertrophy. The impact of the insect’s activity on these patterns of cell development was herein tested in Baccharopelma dracunculifoliae—Baccharis dracunculifolia system. In this system, the microfibrils are oriented perpendicularly to the longest cell axis in elongated cells and randomly in isodiametric ones, either in non-galled or in galled tissues. The isodiametric cells of the abaxial epidermis in non-galled tissues divided and elongated periclinally, forming the outer gall epidermis. The anticlinally elongated cells of the abaxial palisade layer and the isodiametric cells of the spongy parenchyma originated the gall outer cortex with hypertrophied and periclinally elongated cells. The anticlinally elongated cells of the adaxial palisade layer originated the inner cortex with hypertrophied and periclinally elongated cells in young and mature galls and isodiametric cells in senescent galls. The isodiametric cells of the adaxial epidermis elongated periclinally in the inner gall epidermis. The current investigation demonstrates the role of cellulose microfibril reorientation for gall development. Once many factors other than this reorientation act on gall development, it should be interesting to check the possible relationship of the new cell elongation patterns with the pectic composition of the cell walls. 相似文献
992.
Carolin Marlen Degener Tatiana Mingote Ferreira de ázara Rosemary Aparecida Roque Cláudia Torres Code?o Aline Araújo Nobre J?rg Johannes Ohly Martin Geier álvaro Eduardo Eiras 《Memórias do Instituto Oswaldo Cruz》2014,109(8):1030-1040
A longitudinal study was conducted in Manaus, Brazil, to monitor changes of
adult Aedes aegypti (L.) abundance. The objectives were to
compare mosquito collections of two trap types, to characterise temporal changes of
the mosquito population, to investigate the influence of meteorological variables on
mosquito collections and to analyse the association between mosquito collections and
dengue incidence. Mosquito monitoring was performed fortnightly using MosquiTRAPs
(MQT) and BG-Sentinel (BGS) traps between December 2008-June 2010. The two traps
revealed opposing temporal infestation patterns, with highest mosquito collections of
MQTs during the dry season and highest collections of BGS during the rainy seasons.
Several meteorological variables were significant predictors of mosquito collections
in the BGS. The best predictor was the relative humidity, lagged two weeks (in a
positive relationship). For MQT, only the number of rainy days in the previous week
was significant (in a negative relationship). The correlation between monthly dengue
incidence and mosquito abundance in BGS and MQT was moderately positive and negative,
respectively. Catches of BGS traps reflected better the dynamic of dengue incidence.
The findings help to understand the effects of meteorological variables on mosquito
infestation indices of two different traps for adult dengue vectors in Manaus. 相似文献
993.
Male homosexual behavior is observed in many ruminant species; seasonality and isolation from females may affect the display of male–male sexual behavior. Our objectives were to determine whether: 1) homosexual behavior has a seasonal pattern in male goats (Capra hircus); 2) isolation from female goats influences the frequency of the display of homosexual behavior; and 3) the frequency of homosexual behaviors is related to testosterone concentration. Bucks were housed in a pen adjacent to another pen with 3 estrous goats (FC group) or in complete isolation from females (IF group). Homosexual behaviors and testosterone concentrations were recorded in October, December, February and May. Frequencies of penile display and flehmen increased in May and were observed more frequently in the IF than in the FC group. Ano-genital sniffing was more frequent in February and May and was more frequent in IF than in FC bucks. Lateral approaches were more frequent in May, in which period this was more frequently observed in IF bucks. Mount attempts and mounts were only observed in IF bucks. Testosterone concentrations increased from December to February and decreased in May, although they were still greater than in October and December. In May IF bucks had greater testosterone concentrations than FC bucks. Testosterone concentrations were only related to the number of lateral approaches in IF bucks in December. In conclusion, homosexual behavior was more frequent during the late breeding season than during the early and the non-breeding seasons, and in males isolated from females than in males housed near estrous females. Testosterone concentrations appear to be unrelated to homosexual behavior. 相似文献
994.
995.
Priscila Porto Alegre Ferreira Greta Aline Dettke Jorge Luiz Waechter Silvia Teresinha Sfoggia Miotto 《Brittonia》2014,66(3):269-273
A new species of Cuscuta (Convolvulaceae: Cuscuteae) from South America is described, illustrated, and studied under light and scanning electron microscopy. Cuscuta taimensis is similar to Cuscuta racemosa, but differs in having oblong to elliptic calyx lobes and a circumscissile capsule. 相似文献
996.
997.
998.
Nicolay Leme da Cunha Erich Fischer Aline P. Lorenz-Lemke Spencer C. H. Barrett 《Annals of botany》2014,114(8):1637-1649
MethodsStyle morph frequencies were sampled from 73 populations distributed across four flooding regimes differing in depth and duration. Measurements of flower size, sex-organ dimension, pollen size and pollen production were made in selected populations, and pollinator assemblages and their functional traits were recorded.ConclusionsThe similar morph structure and evenness of populations, regardless of flooding regime, suggest that sexual reproduction and clonal dispersal are sufficiently common to prevent the signature of founder events from dominating in a region. However, the pervasive occurrence of biased morph ratios in most populations suggests that many are in a non-equilibrium state. The reduced frequency of the mid-styled morph in trimorphic and dimorphic populations may be associated with the weak self-incompatibility of this morph resulting in selfing and inbreeding depression. Clonality in E. azurea and the weak self-incompatibility of the mid-styled morph may make it more vulnerable to geitonogamous selfing. 相似文献
999.
Marie Dumont Arnaud Lehner Sophie Bouton Marie Christine Kiefer-Meyer Aline Voxeur Jér?me Pelloux Patrice Lerouge Jean-Claude Mollet 《Annals of botany》2014,114(6):1177-1188