Bacillus licheniformis M2-7 Decreases Ochratoxin A Concentrations in Coffee Beans During Storage.

Microbial contamination of coffee beans arises from various factors such as harvesting, handling, and storage practices, during which ochratoxin A (OTA)-producing fungi develop and proliferate. The presence of elevated concentrations of OTA poses a serious health risk to coffee consumers. Therefore, the implementation of a post-harvest treatment involving the use of bacteria known to antagonize OTA-producing fungi constitutes a safe alternative for reducing or eliminating the toxin's concentration in coffee beans. In this study, coffee beans (Coffea arabica L.) were inoculated with Bacillus licheniformis M2-7, after which we monitored fungal growth, in vitro antagonism, and OTA concentration. Our findings demonstrated that coffee beans inoculated with this bacterial strain exhibited a significant decrease in fungal populations belonging to the genera Aspergillus and Penicillium, which are known to produce OTA. Moreover, strain M2-7 decreased the growth rates of these fungi from 67.8% to 95.5% (P < 0.05). Similarly, inoculation with B. licheniformis strain M2-7 effectively reduced the OTA concentration from 24.35 ± 1.61 to 5.52 ± 1.69 µg/kg (P < 0.05) in stored coffee beans. These findings suggest that B. licheniformis M2-7 holds promise as a potential post-harvest treatment for coffee beans in storage, as it effectively inhibits the proliferation of OTA-producing fungi and lowers the toxin's concentration.

Seasonal variation in the response of a monoecious crop to increased temperature and fertilizers.

Climate warming may affect the performance of plants directly through altering vegetative or reproductive traits, and indirectly through modifying interactions with their pollinators. On the other hand, the addition of fertilizers to the soil may increase the quantity and quality of floral rewards, favoring the visitation of pollinators and, consequently, the reproductive success of plants. However, it is still unknown whether fertilizers may counteract the effects of increased temperature on the vegetative, floral, and reproductive traits of plants, as well as on the interaction with their pollinators. The aim of this study is to evaluate the effects of the input of organic and synthetic fertilizers on several vegetative and floral traits, and on the rate of legitimate floral visitors and reproductive success of the squash during two seasons, under a scenario of an increase in ambient temperature. During the dry and the rainy seasons, three vegetative, eleven floral, and two reproductive traits, as well as the duration of visits and visitation rate of legitimate floral visitors were evaluated in squash plants distributed into six treatments in a bifactorial design: temperature (ambient or elevated temperature) and fertilizer (organic, synthetic or without supplementary fertilizers). Contrary to our predictions, we found that an increase of ~1.5°C in ambient temperature, positively influenced several vegetative, floral, and reproductive traits in this crop, and that organic fertilizers, in general, was not better than synthetic fertilizers in improving those traits. Interestingly, the response of the squash and indirectly on their legitimate floral visitors to the increase of temperature and the input of fertilizers vary widely among seasons, suggesting great temporal variation in plant-pollinator responses to temperature and nutrient availability, which makes food security more unpredictable.

Hábitos alimenticios de Caranx vinctus (Perciformes: Carangidae), especie de importancia comercial en la bahía de Acapulco, Guerrero, México / Feeding habits of Caranx vinctus (Perciformes: Carangidae), a commercially important species in Acapulco Bay, Guerrero

Introducción: Caranx vinctus es una especie importante en las pesquerías locales, utilizada como fuente de proteína para el consumo humano, sin embargo, su ecología trófica es poco conocida en las costas de Pacífico mexicano. Objetivo: Conocer los hábitos alimenticios de C. vinctus. Metodología: Se analizaron los contenidos estomacales de 268 ejemplares, capturados mediante el arte de pesca, chinchorro playero, en la sociedad cooperativa Playa las Hamacas, en la Bahía de Acapulco, Guerrero, México. Se aplicó el índice de importancia relativa específica de la presa (% PSIRI) para determinar las principales categorías alimenticias (ítems). La amplitud de la dieta se calculó utilizando el índice de Levin. Las posibles diferencias en la dieta por sexo, madurez sexual o temporada se identificaron a través del índice Morisita Horn y un análisis multivariado ANOSIM. Resultados: Los principales ítems fueron crustáceos representados principalmente por larvas megalopa de Portunoidae (16.51 %), Teleostei (12.7 %), materia orgánica no identificada (11.2 %), y Anchoa ischana (10.6 %) El índice de Levin indica baja amplitud del nicho trófico (Bi = 0.29) por lo que se le puede considerar como un depredador especialista con marcadas preferencias hacia algunos tipos alimentarios. El índice de Morisita Horn indicó que, se presentó un traslape entre las dietas por sexo (hembras y machos Cλ = 0.84), pero no entre madurez sexual (Juveniles y adultos Cλ = 0.56) y temporadas (Lluvias y secas Cλ = 0.03). Un análisis ANOSIM indicó que había diferencias significativas en la dieta de C. vinctus por sexo, madurez sexual y temporada. Conclusión: Se estableció que de manera general C. vinctus es una especie zooplantófaga e ictiófaga (Nivel Trófico = 3.39).

Abtract Introduction: Caranx vinctus is an important species in local fisheries, used as a source of protein for human consumption, however, its trophic ecology is little known on the Mexican Pacific coast. Objective: Know the feeding habits of C. vinctus. Methods: The stomach contents of 268 specimens, captured beach nets, in the Playa Las Hamacas cooperative society, in Acapulco Bay, Guerrero, Mexico, their food items were analyzed. The prey-specific index of relative importance (% PSIRI) was applied to determine the main food categories (breadth was calculated using Levin's index. Possible differences in the diet by sex, sexual maturity, or season were identified through Morisita Horn index and a multivariate ANOSIM analysis. Results: Crustaceans mainly represented by megalopa larvae of Portunoidae (16.51 %), Teleostei (12.7 %), unidentified organic matter (11.2 %), and Anchoa ischana (10.6 %) were the most important food items. The Levin index indicates low amplitude of the trophic niche (Bi = 0.29) so C. vinctus can be considered as a specialist predator with marked preferences towards some food items. The Morisita Horn index indicated that there was an overlap between sexes (females and males Cλ = 0.84), but not between sexual maturity (Juveniles and adults Cλ = 0.56) and seasons (Rainy and dry Cλ = 0.03). ANOSIM analysis indicated that there were significant differences in the diet of C. vinctus by sex, sexual maturity, and season. Conclusion: It was established that in general C. vinctus is a zoplantophage and ichthophagus species (Trophic Level = 3.39).

Influence of pollen limitation and inbreeding depression in the maintenance of incomplete dichogamy in Salvia elegans.

The widespread presence of incomplete dichogamy (i.e., partial separation in time between male and female phases) in flowering plants is a long-standing question in floral evolution. In this study, we proposed four scenarios in which depending on the particular combination of pollen limitation and inbreeding depression, the presence of complete dichogamy, incomplete dichogamy, or adichogamy may be favored. Moreover, we evaluated the role of pollen limitation and inbreeding depression in a natural population of Salvia elegans to test the validity of our predicted scenarios. Our results indicate that S. elegans is partially protandrous as pollen viability and stigma receptivity overlap in the last days of life of the flower. Furthermore, through pollination treatments, we found no evidence of pollen limitation or inbreeding depression in any of the evaluated fitness components. As expected by one of the proposed scenarios, incomplete dichogamy seems to be favored in plants with absence of inbreeding depression and pollen limitation as a way to diminish interference between male and female functions.

A quantitative review of pollination syndromes: do floral traits predict effective pollinators?

The idea of pollination syndromes has been largely discussed but no formal quantitative evaluation has yet been conducted across angiosperms. We present the first systematic review of pollination syndromes that quantitatively tests whether the most effective pollinators for a species can be inferred from suites of floral traits for 417 plant species. Our results support the syndrome concept, indicating that convergent floral evolution is driven by adaptation to the most effective pollinator group. The predictability of pollination syndromes is greater in pollinator-dependent species and in plants from tropical regions. Many plant species also have secondary pollinators that generally correspond to the ancestral pollinators documented in evolutionary studies. We discuss the utility and limitations of pollination syndromes and the role of secondary pollinators to understand floral ecology and evolution.

Influence of pollination specialization and breeding system on floral integration and phenotypic variation in Ipomoea.

Natural selection should reduce phenotypic variation and increase integration of floral traits involved in placement of pollen grains on stigmas. In this study, we examine the role of pollinators and breeding system on the evolution of floral traits by comparing the patterns of floral phenotypic variances and covariances in 20 Ipomoea species that differ in their level of pollination specialization and pollinator dependence incorporating phylogenetic relatedness. Plants with specialized pollination (i.e., those pollinated by one functional group or by few morphospecies) displayed less phenotypic variation and greater floral integration than generalist plants. Self-compatible species also displayed greater floral integration than self-incompatible species. Floral traits involved in pollen placement and pick up showed less variation and greater integration than floral traits involved in pollinator attraction. Analytical models indicate that both breeding system and the number of morphospecies had significant effects on floral integration patterns although only differences in the former were significant after accounting for phylogeny. These results suggest that specialist/self-compatible plants experience more consistent selection on floral traits than generalist/self-incompatible plants. Furthermore, pollinators and breeding system promote integration of floral traits involved in pollen placement and pick up rather than integration of the whole flower.

Effects of habitat disruption on the activity of nectarivorous bats (Chiroptera: Phyllostomidae) in a dry tropical forest: implications for the reproductive success of the neotropical tree Ceiba grandiflora.

In the tropical dry forest of the central Pacific coast of Mexico the pollination and reproductive success of the bombacaceous tree Ceiba grandiflora was negatively affected by habitat disruption. Two of the three bat species that function as effective pollinators for this species ( Glossophaga soricina and Musonycteris harrisoni) visited flowers found in trees in disturbed habitats significantly less than trees found in undisturbed habitats. A similar pattern was observed for the effective bat pollinator, Leptonycteris curasoae; however the difference was not significant. The three nectarivorous bats that functioned as effective pollinators of C. grandiflora also visited flowers to exclusively feed on pollen by biting or pulling off an anther (see Fig. S1 of Electronic Supplementary Material). The number of pollen grains deposited on stigmas from flowers in undisturbed areas was significantly greater than from flowers in disturbed habitats. The greater visitation rate and the greater number of pollen grains deposited on flowers from trees in undisturbed forest resulted in a significantly greater fruit set for trees in these areas. Our study demonstrates the negative effect that habitat disruption has on bat pollinators in tropical dry forest ecosystems and documents the negative consequences for the plants they pollinate.