The transcriptional landscape of the developmental switch from regular pollen maturation towards microspore-derived plant regeneration in barley

Plant formation from in vitro-cultivated microspores involves a complex network of internal and environmental factors.Haploids/doubled haploids(DHs)derived from in vitro-cultured microspores are widely used in plant breeding and genetic engineering.However,the mechanism underlying the developmental switch from regular pollen maturation towards microspore-derived plant regeneration remains poorly defined.Here,RNA-sequencing was employed to elucidate the transcriptional landscapes of four early stages of microspore embryogenesis(ME)in barley cultivars Golden Promise and Igri,which exhibit contrasting responsiveness to microspore-derived plant formation.Our experiments revealed fundamental regulatory networks,specific groups of genes,and transcription factor(TF)families potentially regulating the developmental switch.We identified a set of candidate genes crucial for genotype-dependent responsiveness/recalcitrance to ME.Our high-resolution temporal transcriptome atlas provides an important resource for future functional studies on the genetic control of microspore developmental transition.

Developing fertility control for rodents: a framework for researchers and practitioners

Fertility control is often heralded as a humane and effective technique for management of overabundant wildlife,including rodents.The intention is to reduce the use of lethal and inhumane methods,increase farm productivity and food security as well as reduce disease transmission,particularly of zoonoses.We developed a framework to guide researchers and stakeholders planning to assess the effectiveness of a potential contraceptive agent for a particular species.Our guidelines describe the overarching research questions which must be sequentially addressed to ensure adequate data are collected so that a contraceptive can be registered for use in broad-scale rodent management.The framework indicates that studies should be undertaken iteratively and,at times,in parallel,with initial research being conducted on(1)laboratory-based captive assessments of contraceptive effects in individuals;(2)simulation of contraceptive delivery using bait markers and/or surgical sterilization of different proportions of afield-based or enclosure population to determine how population dynamics are affected;(3)development of mathematical models which predict the outcomes of different fertility control scenarios;and(4)implementation of large-scale,replicated trials to validate contraceptive efficacy under various management-scalefield situations.In some circumstances,fertility control may be most effective when integrated with other methods(e.g.some culling).Assessment of non-target effects,direct and indirect,and the environmental fate of the contraceptive must also be determined.Developing fertility control for a species is a resource-intensive commitment but will likely be less costly than the ongoing environmental and economic impacts by rodents and rodenticides in many contexts.

Ethyl-iophenoxic acid as a quantitative bait marker for small mammals

Bait markers are indispensable for ecological research but in small mammals,most markers are invasive,expensive and do not enable quantitative analyses of consumption.Ethyl-iophenoxic acid(Et-IPA)is a non-toxic,quantitative bait marker,which has been used for studying bait uptake in several carnivores and ungulates.We developed a bait with Et-IPA,assessed its palatability to common voles(Microtus arvalis),and determined the dose-residue-relation for this important agricultural pest rodent species.Et-IPA concentrations of 40 to 1280μg Et-IPA per g bait were applied to wheat using sunflower oil or polyethylene glycol 300 as potential carriers.In a laboratory study,common voles were offered the bait and blood samples were collected 1,7,and 14 days after consumption.The samples were analyzed with LC-ESI-MS/MS for blood residues of Et-IPA.Sunflower-oil was the most suitable bait carrier.Et-IPA seemed to be palatable to common voles at all test concentrations.Dose-dependent residues could be detected in blood samples in a dose-dependent manner and up to 14 days after uptake enabling generation of a calibration curve of the dose-residue relationship.Et-IPA was present in common vole blood for at least 14 days,but there was dissipation by 33–37%depending on dose.Et-IPA meets many criteria for an“ideal”quantitative bait marker for use in futurefield studies on common voles and possibly other small mammal species.

Gut microbiota research nexus:One Health relationshipbetween human,animal,and environmental resistomes

The emergence and rapid spread of antimicrobial resistance is of global public health concern.The gut microbiota harboring diverse commensal and opportunistic bacteria that can acquire resistance via horizontal and vertical gene transfers is considered an important reservoir and sink of antibiotic resistance genes(ARGs).In this review,we describe the reservoirs of gut ARGs and their dynamics in both animals and humans,use the One Health perspective to track the transmission of ARG-containing bacteria between humans,animals,and the environment,and assess the impact of antimicrobial resistance on human health and socioeconomic development.The gut resistome can evolve in an environment subject to various selective pressures,including antibiotic administration and environmental and lifestyle factors(e.g.,diet,age,gender,and living conditions),and interventions through probiotics.Strategies to reduce the abundance of clinically relevant antibiotic-resistant bacteria and their resistance determinants in various environmental niches are needed to ensure the mitigation of acquired antibiotic resistance.With the help of effective measures taken at the national,local,personal,and intestinal management,it will also result in preventing or minimizing the spread of infectious diseases.This review aims to improve our understanding of the correlations between intestinal microbiota and antimicrobial resistance and provide a basis for the development of management strategies to mitigate the antimicrobial resistance crisis.

“Macrobot”:An Automated Segmentation-Based System for Powdery Mildew Disease Quantification

Managing plant diseases is increasingly difficult due to reasons such as intensifying the field production,climatic change-driven expansion of pests,redraw and loss of effectiveness of pesticides,rapid breakdown of the disease resistance in the field,and other factors.The substantial progress in genomics of both plants and pathogens,achieved in the last decades,has the potential to counteract this negative trend,however,only when the genomic data is supported by relevant phenotypic data that allows linking the genomic information to specific traits.We have developed a set of methods and equipment and combined them into a“Macrophenomics facility.”The pipeline has been optimized for the quantification of powdery mildew infection symptoms on wheat and barley,but it can be adapted to other diseases and host plants.The Macrophenomics pipeline scores the visible powdery mildew disease symptoms,typically 5-7 days after inoculation(dai),in a highly automated manner.The system can precisely and reproducibly quantify the percentage of the infected leaf area with a theoretical throughput of up to 10000 individual samples per day,making it appropriate for phenotyping of large germplasm collections and crossing populations.

Effect of toasting grain silages from field peas(Pisum sativum)and field beans(Vicia faba)on in vitro gas production,methane production,and post-ruminal crude protein content

Legume grains such as field peas and field beans can be produced on a local level,and may be reliable sources of dietary protein and energy apart from common soybean and rapeseed meals.In ruminants,protein,starch,and carbohydrates from peas and field beans are fermented in large part before reaching the small intestine.The objective of this study was to evaluate the effects of a combination of ensiling and hydro-thermic treatment(i.e.,toasting at 160℃for 30 min)of grains of peas and field beans on the concentrations of post-ruminal crude protein(PRCP)and rumen-undegraded protein(RUP).Moreover,24-h gas production and methane production were measured.For this,an in vitro batch culture system with ruminal fluid from sheep was used.Rumen-undegraded protein was determined using the Streptomyces griseus protease test.Scanning electron micrographs were used to visualize morphological changes of starch granules and their joint matrices in peas and field beans after ensiling,toasting,or a combination of both.Native pea grains contained crude protein(CP)at 199 g/kg DM,PRCP at 155 g/kg DM at a ruminal passage rate of 0.08/h(Kp8),RUP at 33 g/kg DM at Kp8,and starch at 530 g/kg DM.Native field beans contained CP at 296 g/kg DM,PRCP at 212 g/kg DM at Kp8,RUP at 54 g of/kg DM at Kp8,and starch at 450 g/kg DM.The PRCP did not considerably differ among native and treated peas or field beans.Especially in the peas,RUP at Kp8 increased after ensiling by 10 g/kg DM(i.e.,30%;P<0.05).Toasting increased RUP(Kp8)in ensiled peas by another 28%(P<0.05).Toasting had no effect on PRCP or RUP when the peas or field beans were not ensiled before.Gas and methane production were not affected by any treatment,and scanning electron micrographs did not reveal structural changes on the starches doubtless of any treatment.Protein seemed to be more affected by treatment with ensiled+toasted peas than with ensiled+toasted field beans,but starches and other carbohydrates from both legumes remained unaffected.