The effectiveness of flower strips and hedgerows on pest control,pollination services and crop yield: a quantitative synthesis

Floral plantings are promoted to foster ecological intensification of agriculture through provisioning of ecosystem services. However, a comprehensive assessment of the effectiveness of different floral plantings, their characteristics and consequences for crop yield is lacking. Here we quantified the impacts of flower strips and hedgerows on pest control (18 studies) and pollination services (17 studies) in adjacent crops in North America, Europe and New Zealand. Flower strips, but not hedgerows, enhanced pest control services in adjacent fields by 16% on average. However, effects on crop pollination and yield were more variable. Our synthesis identifies several important drivers of variability in effectiveness of plantings: pollination services declined exponentially with distance from plantings, and perennial and older flower strips with higher flowering plant diversity enhanced pollination more effectively. These findings provide promising pathways to optimise floral plantings to more effectively contribute to ecosystem service delivery and ecological intensification of agriculture in the future.     

Light controls stamen elongation via cryptochromes,phytochromes and COP1 through HY5 and HYH

In Arabidopsis, stamen elongation, which ensures male fertility, is controlled by the auxin response factor ARF8, which regulates the expression of the auxin repressor IAA19. Here, we uncover a role for light in controlling stamen elongation. By an extensive genetic and molecular analysis we show that the repressor of light signaling COP1, through its targets HY5 and HYH, controls stamen elongation, and that HY5 – oppositely to ARF8 – directly represses the expression of IAA19 in stamens. In addition, we show that in closed flower buds, when light is shielded by sepals and petals, the blue light receptors CRY1/CRY2 repress stamen elongation. Coherently, at flower disclosure and in subsequent stages, stamen elongation is repressed by the red and far‐red light receptors PHYA/PHYB. In conclusion, different light qualities – sequentially perceived by specific photoreceptors – and the downstream COP1–HY5/HYH module finely tune auxin‐induced stamen elongation and thus male fertility.     

Length–weight relationships of five selected demersal fishes from the Cabo Verde Islands (eastern-central Atlantic)

The length–weight relationships (LWR) were estimated for five selected demersal marine fishes from the relatively undisturbed shelves and slopes of the Cabo Verde Islands. Most of them were of ecological and/or commercial interest. Occasional sampling was carried out during different fisheries research projects. LWRs were taken for the following bycatch species for which no such estimates exists in the science literature: Myroconger compressus, Synaphobranchus affinis, Physiculus cyanostrophus, Physiculus caboverdensis and Canthidermis maculata. Total length and fork length (to the nearest 0.1 cm) and total weight (to the nearest 0.1 g) were determined. The resulting length–weight equations are characterized by a high accompanying coefficient of correlation. The present data help improving the knowledge base needed for further fish biology studies and fisheries management.     

Phenotypic plasticity of invasive Carpobrotus edulis modulates tolerance against herbivores

The anthropogenic movement of species has favoured the introduction of invasive plants worldwide. Invasive plants are frequently released from their natural enemies; however, new associations with generalist herbivores may induce defence mechanisms of non-native plants. Defensive traits are often directly related to the highly competitive ability, but also to potential antagonisms and mutualisms that they can establish with soil microorganisms. Here, we examined whether the intraspecific competition and soil microorganisms influence the morphological and physiological traits of Carpobrotus edulis when is being attacked by the native generalist snail Theba pisana. To achieve this, we grew two C. edulis individuals in separate and same pots filled with live or sterile sand, and with or without T. pisana. Our results indicated that herbivory induced an increase of shoot biomass in attacked C. edulis individuals (i.e., treated donor plants), as well as in un-attacked neighbouring individuals co-growing in the same pot (i.e., untreated recipient plants). Nevertheless, intraspecific competition nor soil microorganisms did not affect the growth of C. edulis despite reduced physiological activity and damage caused by the herbivore. Overall, our findings revealed that C. edulis individuals tolerate snail attack by inducing a compensatory growth response. We conclude that phenotypic plasticity of invasive C. edulis favours tolerance against herbivores, but we also suggest that plant-plant interactions probably determine the plant growth of un-attacked neighbouring C. edulis individuals, thus favouring their invasion mechanisms.

     

Nighttime Sugar Starvation Orchestrates Gibberellin Biosynthesis and Plant Growth in Arabidopsis

A plant’s eventual size depends on the integration of its genetic program with environmental cues, which vary on a daily basis. Both efficient carbon metabolism and the plant hormone gibberellin are required to guarantee optimal plant growth. Yet, little is known about the interplay between carbon metabolism and gibberellins that modulates plant growth. Here, we show that sugar starvation in Arabidopsis thaliana arising from inefficient starch metabolism at night strongly reduces the expression of ent-kaurene synthase, a key regulatory enzyme for gibberellin synthesis, the following day. Our results demonstrate that plants integrate the efficiency of photosynthesis over a period of days, which is transduced into a daily rate of gibberellin biosynthesis. This enables a plant to grow to a size that is compatible with its environment.     

Homoploid hybrid speciation in Doronicum L. (Asteraceae)? Morphological,karyological and molecular evidences

Abstract

The first unambiguous documentation of hybridism in the genus Doronicum (Senecioneae – Asteraceae) is reported. All our morphological, karyological and molecular data concur to indicate that Doronicum × minutilloi Peruzzi hybr. nov. (2n = 60) is a hybrid growing in Monti Aurunci (Central Italy), originated from the spontaneous crossing D. orientale Hoffm. (2n = 60) × D. columnae Ten. (2n = 60). This new hybrid shows a slightly higher morphological, karyotypic and ribotypic affinity with D. columnae, but shares a trnL-trnF IGS haplotype with D. orientale, and co-occurs with the latter species only; it has reduced fertility and a high potential for vegetative propagation through rhizome fragmentation. Our results led us to suspect in fieri homoploid hybrid speciation.     

How Skill Expertise Shapes the Brain Functional Architecture: An fMRI Study of Visuo-Spatial and Motor Processing in Professional Racing-Car and Na?ve Drivers

The present study was designed to investigate the brain functional architecture that subserves visuo-spatial and motor processing in highly skilled individuals. By using functional magnetic resonance imaging (fMRI), we measured brain activity while eleven Formula racing-car drivers and eleven ‘naïve’ volunteers performed a motor reaction and a visuo-spatial task. Tasks were set at a relatively low level of difficulty such to ensure a similar performance in the two groups and thus avoid any potential confounding effects on brain activity due to discrepancies in task execution. The brain functional organization was analyzed in terms of regional brain response, inter-regional interactions and blood oxygen level dependent (BOLD) signal variability. While performance levels were equal in the two groups, as compared to naïve drivers, professional drivers showed a smaller volume recruitment of task-related regions, stronger connections among task-related areas, and an increased information integration as reflected by a higher signal temporal variability. In conclusion, our results demonstrate that, as compared to naïve subjects, the brain functional architecture sustaining visuo-motor processing in professional racing-car drivers, trained to perform at the highest levels under extremely demanding conditions, undergoes both ‘quantitative’ and ‘qualitative’ modifications that are evident even when the brain is engaged in relatively simple, non-demanding tasks. These results provide novel evidence in favor of an increased ‘neural efficiency’ in the brain of highly skilled individuals.     

Roux-en-Y Gastric Bypass Increases Intravenous Ethanol Self-Administration in Dietary Obese Rats

Roux-en-Y gastric bypass surgery (RYGB) is an effective treatment for severe obesity. Clinical studies however have reported susceptibility to increased alcohol use after RYGB, and preclinical studies have shown increased alcohol intake in obese rats after RYGB. This could reflect a direct enhancement of alcohol’s rewarding effects in the brain or an indirect effect due to increased alcohol absorption after RGYB. To rule out the contribution that changes in alcohol absorption have on its rewarding effects, here we assessed the effects of RYGB on intravenously (IV) administered ethanol (1%). For this purpose, high fat (60% kcal from fat) diet-induced obese male Sprague Dawley rats were tested ∼2 months after RYGB or sham surgery (SHAM) using both fixed and progressive ratio schedules of reinforcement to evaluate if RGYB modified the reinforcing effects of IV ethanol. Compared to SHAM, RYGB rats made significantly more active spout responses to earn IV ethanol during the fixed ratio schedule, and achieved higher breakpoints during the progressive ratio schedule. Although additional studies are needed, our results provide preliminary evidence that RYGB increases the rewarding effects of alcohol independent of its effects on alcohol absorption.