Differential reproductive success in Cassia fistula in different habitants-A case of pollinator limitations?

Differences in flower success patterns in two habitat types that differed drastically with respect to rainfall, tree density and species composition were studied at Mudumalai wildlife sanctuary, India. Observations on phenological patterns of two species, Cassia fistula and Gmelina arborea, were made from April 1988 through June 1990. Quantitative data on flower-fruit ratio, insect visitation rates, pollen grain per stigma and the number of fruits per tree were recorded. Data were also collected on the number of pollen deposited on the stigma after different types of bees visited the flower. The data suggested that only carpenter bees (Xylocopa spp) effect pollination in C. fistula. The differences in fruit-flower ratios were attributed to the differences in insect visitation rates to inflorescences between sites. The low pollen number per stigma and the resultant reduction in reproductive success in C. fistula are attributed to the competing species G. arborea receiving more visitations from pollinators in the wetter site. These results suggest that pollinator limitation is another constraint in reproductive success of plants.

Halichondria sulfonic acid, a new HIV-1 inhibitory guanidino-sulflonic acid, and halistanol sulfate isolated from the marine sponge Halichondria rugosa Ridley & Dendy

A new sulfur-containing guanidino derivative, halichondria sulfonic acid (1) showing anti-HIV-1 activity, and halistanol trisulfate (2) with anti-tumor activity have been isolated from the marine sponge Halichondria rugosa Ridley & Dendy collected in the

Genetic parentage in the squat lobsters Munida rugosa and M. sarsi (Crustacea, Anomura, Galatheidae)

Munida is the most diverse and cosmopolitan genus of the galatheid squat lobsters. The group has attracted much attention in recent years from both systematic and evolutionary perspectives, yet information on the biology, ecology, and evolution of this genus is very limited. We investigated the genetic parentage of two North Atlantic species; Munida rugosa and M. sarsi sampled from the Clyde Sea on the west coast of Scotland. Microsatellite markers were used to establish the parental contribution from embryos of berried females (M. rugosa, n=25 and M. sarsi, n=5). The frequency of multiple paternity observed in both species (86% for M. rugosa and 100% for M. sarsi) is the highest ever reported for any marine crustaceans. Invariably more than two sires were involved in each case (minimum of two to three for M. rugosa and four for M. sarsi). Findings indicate that multiple paternity is likely to be the norm in both species. Within most multiply sired broods, sire contribution was highly skewed towards a single male (66% of broods for M. rugosa and 100% for M. sarsi). Furthermore, embryos from different sires were randomly distributed across the female's brood patch. This is the first report of multiple paternity in galatheids. While a number of theories can account for the high incidence of multiple paternity in these species (e.g. convenience polyandry as a result of cryptic female choice, forced copulations, the influence of fishing pressures), at present it is not possible to disentangle their individual and/or combined effects.

Evaluación del uso de quercus rugosa née y quercus resinosa liebm en la alimentación de pequeños rumiantes.

Tesis (Doctor en Ciencias con acentuación en Alimentos) UANL, 2014.

Lipase Production by Candida rugosa

Strain improvement is one of the major objectives for maximizing the microbial production of industrially significant primary and secondary metabolites. This goal can be achieved by judicious tuning of the organisms by monitoring its growth parameters and optimizing adequate supply of micro and macro nutrients, inducers, pH, temperature and other factors which control fermentation. Though C. rugosa has been under extensive studies for lipases, maximum world production is only 36 units. In fact, in India, enhanced production conditions for lipases have not yet been initiated. C. rugosa has been cultivated in diverse environments like liquid, semi-solid, solid—state and immobilized conditions, though major emphasis is on SmF or suspension culture. Hence the present investigations mainly focused on increasing the yield by adjusting the physico-chemical growth parameters and to characterize the lipase isoforms secreted by C. rugosa in the culture medium. Maximum possible improved methods were investigated to achieve these objectives. Within this under-optimised background, enhancement of lipase production and its characterization were investigated, employing modified liquid, semi-solid, solid—state and immobilized fermentation strategies

Anti-proliferative effect of rhein, an anthraquinone isolated from Cassia species, on Caco-2 human adenocarcinoma cells

Objective: In recent years the use of anthraquinone laxatives, in particular senna, has been associated with damage to the intestinal epithelial layer and an increased risk of developing colorectal cancer. In the present study we evaluated the cytotoxicity of rhein, the active metabolite of senna, on human colon adenocarcinoma cells (Caco-2) and its effect on cell proliferation. Methods: Cytotoxicity studies were performed using MTT, NR and TEER assays whereas 3H-thymidine incorporation and western blot analysis were used to evaluate the effect of rhein on cell proliferation. Moreover, for genoprotection studies Comet assay and oxidative biomarkers measurement (malondialdehyde and reactive oxygen species) were used. Results: Rhein (0.1-10μg/ml) had no significant cytotoxic effect on proliferating and differentiated Caco-2 cells. Rhein (0.1 and 1 μg/ml) significantly reduced cell proliferation as well as MAP kinase activation; by contrast, at the high concentration (10μg/ml) rhein significantly increased cell proliferation and ERK phosphorylation. Moreover, rhein (0.1-10μg/ml) (i) did not adversely affect the integrity of tight junctions and hence epithelial barrier function, (ii) did not induce DNA damage rather it was able to reduce H2O2-induced DNA damage and (iii) significantly inhibited the increase in malondialdehyde and ROS levels induced by H2O2/Fe2+. Conclusions: Rhein, was devoid of cytotoxic and genotoxic effects in colon adenocarcinoma cells. Moreover, at concentrations present in the colon after a human therapeutic dosage of senna, rhein inhibited cell proliferation via a mechanism which seems to involve directly the MAP kinase pathway. Finally, rhein prevents the DNA damage probably via an anti-oxidant mechanism.

Antiparasitic activity of biochanin A, an isolated isoflavone from fruits of Cassia fistula (Leguminosae)

The fractionation through bioguided antileishmanial activity of the dichloromethane extract of Cassia fistula fruits (Leguminosae) led to the isolation of the active isoflavone biochanin A, identified by spectroscopic methods. This compound showed 50% effective concentration (EC(50)) value of 18.96 mu g/mL against promastigotes of Leishmania (L.) chagasi. The cytotoxicity of this substance against peritoneal macrophages resulted in an EC(50) value of 42.58 mu g/mL. Additionally, biochanin A presented an anti-Trypanosoma-cruzi activity, resulting in an EC(50) value of 18.32 mu g/mL and a 2.4-fold more effectiveness than benznidazole. These results contribute with novel antiprotozoal compounds for future drug design studies.

Competition of sicklepod, cassia obtusifolia l., densities on soybean, glycine max (l.) merr., at variable row distance

Competition studies with soybeans, Glycine max (L.) Merr. "Bragg." and sicklepod, Cassia obtusifolia L., were conducted at the Agricultural Research and Education Center of the University of Florida in Quincy, Florida. Two field experiments were established, one on May 22, 1975. and the other four weeks later, on June 19, 1975, to determine the competitive effects of various sicklepod densities and the influences of soybean row distances on weed dry matter, soybear plant characteristics, yield components and seed yield, and on soil nutrient content. Control, low, medium, and high sicklepod densities in the first experiment were O, 25,000, 53,000, and 77,000 p1ants/ha, respectively; while the second experiment presented control, low, medium, and high sicklepod densities of O, 36,000, 68,000, and 122,000 plants/ha, respectively. Three soybean row distance treatments were tested using a constant pattern of 90-, 60-, and 45-cm widths throughout the growing season. Three other treatments, evaluated in a variable patern, were initially seeded in 30-cm row widths. Five weeks after planting, an appropriate number of soybean rows were harvested from the 30"cm pattern to establish row distances of 90, 60, and 30-60 cm for the remainder of the season. ln the greenhouse a test was conducted to evaluate the effects af those variables on seed germination and seedling vigor for the next soybean generation. As a result of full-season sicklepod competition, soybean plants were less branched, set fewer leaves, and presented thinner stems as compared to the control. However, height of soybean plants was not affected by the presence of sicklepod. ln one of the two experiments, number of nodes decreased for soybeans under weed campetition. The yield components--number of pods; number of seeds, and seed yield per soybean plant--were all similarly reduced due to weed competition. Seeds per pod were decreased to a lesser extent. Soybean seed yields per unit area were significantly diminished by increasing levels af sicklepod ínfestation. While the control produced 3120 kg/ha, the sicklepod densities of 25,000, 53,000, and 77,000 plants/ha reduced seed yíelds 47, 65, and 73%, respectively. As soybean row distances decreased, number of branches, number of leaves, and stem diameter of soybeans decreased. However, the height of soybean plants increased with narrwing of row width. The components of seed yield--number of pods, number of seeds, and seed yield per soybean plant--diminished as row spacing was reduced. Maximum difference between row distances for these attributes was attained for soybean plants under weed-free conditions. Generally, as row width decreased, soybean seed yield per unit area increased. Specifically, soybear.s in 90-cm rows, either in constant or variable row pattern, yielded less than soybeans in 60- and 30-60-cm rows in the variable pattern. Soil contents of phosphorus, potassium, calcium, and magnesium were not affected by the various levels of sicklepod and soybean populalions. Neither the sicklepod densities nor the soybean row distances influenced seed germination and seedling vigor in the next soybean generation. Sicklepod was a strong competitor with soybeans at all density ranges investigated. Because sicklepod grows taller than soybeans during the reproductive stages of the crop, limited success can be reached by varying row spacing alone. However, this practice is considered an integral measure to complement other methods of sicklepod control. Compared to constant rows, the soybean cropping system using variable row spacings presents the choice of planting soybeans at close row spacings to provide early competition with weeds and the possibility of obtaining a forage crop after the first month of growth, without any decreases on the final seed yields.

Entomofauna visitante das flores de Cassia spectabilis (L.) D C. (Leguminosae)

Realizaram-se estudos sobre sistemas de reprodução de Cassia spectabilis (L.) D C. (Leguminosae) observando-se a diversidade, freqüência e constância dos insetos visitantes em diferentes horários. Também testou-se a influência dos fatores ambientais em relação às visitas. Os resultados de polinização manual sugerem que C. spectabilis é autocompatível, porém, a xenogamia é o sistema de reprodução predominante. As inflorescências foram visitadas por uma grande quantidade de insetos, havendo predominância de abelhas. O horário de maior ocorrência dos insetos nas flores de C. spectabilis foi das 8 às 14 h e de menor ocorrência entre 7 e 8 h e das 17 às 18 h. Quanto ao comportamento dos insetos em relação à flor de C. spectabilis, observou-se que Xylocopa frontalis Olivier, X. suspecta Camargo & Moure, Bombus morio Swederus e Centris scopipes Friese possuem comportamento e morfologia adequados aos polinizadores legítimos; C. similis F., Oxaea flavescens Klug e Epicharis rustica flava Cockerell foram considerados polinizadores ocasionais. Pseudaugochloropsis graminea (F.), Tetragonisca angustula Latreille e A. mellifera L. foram considerados pilhadores. A polinização por vibração é o método usado pelas abelhas para coleta de pólen.