The role of crop-pollinator relationships in breeding for pollinator-friendly legumes: from a breeding perspective

Breeders are encouraged to develop breeding approaches that strive to integrate food production into the healthy functioning of agro-ecosystems. In the case of legumes, this approach should preserve bee fauna by providing suitable floral resources within the crops themselves. In parallel, legume breeding for sustainable agriculture is linked to the development of environmental services. Foraging places and nesting sites for solitary and social bees are some of the ecological services provided for legumes. Crops with floral attractiveness and rewards for insects can be used to enhance pollinator conservation as well as crop yield and yield stability. We analyze how understanding crop-pollinator relationships (CPR) can contribute to the production of high-yielding and pollinator-friendly varieties by examining: (1) The status of knowledge on mating systems and floral traits; (2) The contribution of CPR understanding to plant breeding for both hybrid-seed production and open-pollinated population improvement.     

Paraneoplastic hypoglycemia in a diabetic dog with an insulin growth factor-2-producing mammary carcinoma

A 6-year-old intact female Labrador Retriever had diabetes mellitus, which had been difficult to control with insulin. The dog also had a solid ductal mammary carcinoma with very rapid growth, which was temporally related to onset of hypoglycemia. Eight months after initial diagnosis of diabetes, the dog had a hypoglycemic crisis. Insulin administration was stopped and serum glucose concentration returned to normal. Three months after discontinuing insulin, another hypoglycemic crisis occurred. During subsequent months, serum glucose concentrations remained at life-threatening levels (1.64-2.12 mmol/L, reference interval 4.44-6.66 mmol/L) simultaneously with an increase in the size of the mammary tumor, which reached a diameter of about 16 cm. At the time of surgery for removal of the tumor serum glucose concentration was 2.20 mmol/L and was then monitored every 3 hours after excision of the tumor. The glucose concentration continued to rise and reached 9.99 mmol/L 12 hours after the removal of the mammary tumor. Immunohistochemical staining demonstrated expression of insulin growth factor-2 by tumor cells, which apparently had caused the hypoglycemia during tumor growth even in a diabetic dog. Hyperglycemia associated with diabetes was pronounced after excision of the tumor and had been masked by the paraneoplastic effect of the tumor.     

Parameterization of the duration of infection stages of serotype O foot-and-mouth disease virus: an analytical review and meta-analysis with application to simulation models

Foot-and-mouth disease (FMD) is considered one of the most important infectious diseases of livestock because of the devastating economic consequences that it inflicts in affected regions. The value of critical parameters, such as the duration of the latency or the duration of the infectious periods, which affect the transmission rate of the FMD virus (FMDV), are believed to be influenced by characteristics of the host and the virus. Disease control and surveillance strategies, as well as FMD simulation models, will benefit from improved parameter estimation. The objective of this study was to quantify the distributions of variables associated with the duration of the latency, subclinical, incubation, and infectiousness periods of FMDV transmission. A double independent, systematic review of 19 retrieved publications reporting results from experimental trials, using 295 animals in four reference laboratories, was performed to extract individual values related to FMDV transmission. Probability density functions were fitted to data and a set of regression models were used to identify factors associated with the assessed parameters. Latent, subclinical, incubation, and infectious periods ranged from 3.1 to 4.8, 2 to 2.3, 5.5 to 6.6, and 3.3 to 5.7 days, respectively. Durations were significantly (p < 0.05) associated independently with route of exposure, type of donor, animal species, strains, characteristics of sampling, and clinical signs. These results will contribute to the improvement of disease control and surveillance strategies and stochastic models used to simulate FMD spread and, ultimately, development of cost-effective plans to prevent and control the potential spread of the disease in FMD-free regions of the world.     

Detection and identification of Xanthomonas arboricola pv. pruni from symptomless plant material: results of an Italian test performance study

Xanthomonas arboricola pv. pruni, the causal agent of bacterial spot disease of stone fruits, is a regulated quarantine pathogen in the European Union, listed as an A2 pest by the European and Mediterranean Plant Protection Organization (EPPO). Because detection and identification of this pathogen is key for its management and to ensure the production of pest free propagation material, it should be based on reliable tests, in particular when dealing with symptomless material. The current EPPO diagnostic Standard (PM 7/64) does not provide specific molecular methods for detection of this pest. The present paper summarizes the results of a test‐performance study (TPS) to validate, at a national level, a detection procedure for this bacterium. A working group was established in order to evaluate the performance criteria for tests included in the current EPPO Standard, and for a conventional PCR. On the basis of the obtained performance criteria, a diagnostic procedure was elaborated and then applied to perform an inter‐laboratory comparison. Screening tests for the detection of the bacterium on symptomless plant material based on IF and/or PCR were proposed, in parallel with isolation on agar media. For identification two methods were suggested: a molecular test or IF. This paper reports on the results of the TPS and proposes a flow diagram for the detection and identification of X. arboricola pv. pruni.     

Isotope labeling studies on the formation of 5-(hydroxymethyl)-2-furaldehyde (HMF) from sucrose by pyrolysis-GC/MS

Although it is generally assumed that the reactivity of sucrose, a nonreducing sugar, in the Maillard reaction is due to its hydrolysis into free glucose and fructose, however, no direct evidence has been provided for this pathway, especially in dry and high temperature systems. Using specifically (13)C-labeled sucrose at C-1 of the fructose moiety, HMF formation was studied at different temperatures. Under dry pyrolytic conditions and at temperatures above 250 degrees C, 90% of HMF originated from fructose moiety and only 10% originated from glucose. Alternatively, when sucrose was refluxed in acidic methanol at 65 degrees C, 100% of HMF was generated from the glucose moiety. Moreover, the relative efficiency of the known HMF precursor 3-deoxyglucosone to generate HMF was compared to that of glucose, fructose and sucrose. Glucose exhibited a much lower conversion rate than 3-deoxyglucosone, however, both fructose and sucrose showed much higher conversion rates than 3-deoxyglucosone thus precluding it as a major precursor of HMF in fructose and sucrose solutions. Based on the data generated, a mechanism of HMF formation from sucrose is proposed. According to this proposal sucrose degrades into glucose and a very reactive fructofuranosyl cation. In dry systems this cation can be effectively converted directly into HMF.     

Diverse bacterial PKS sequences derived from okadaic acid-producing dinoflagellates

Okadaic acid (OA) and the related dinophysistoxins are isolated from dinoflagellates of the genus Prorocentrum and Dinophysis. Bacteria of the Roseobacter group have been associated with okadaic acid producing dinoflagellates and have been previously implicated in OA production. Analysis of 16S rRNA libraries reveals that Roseobacter are the most abundant bacteria associated with OA producing dinoflagellates of the genus Prorocentrum and are not found in association with non-toxic dinoflagellates. While some polyketide synthase (PKS) genes form a highly supported Prorocentrum clade, most appear to be bacterial, but unrelated to Roseobacter or Alpha-Proteobacterial PKSs or those derived from other Alveolates Karenia brevis or Crytosporidium parvum.