An integrated approach for increasing breeding efficiency in apple and peach in Europe

Despite the availability of whole genome sequences of apple and peach,there has been a considerable gap between genomics and breeding.To bridge the gap,the European Union funded the FruitBreedomics project(March 2011 to August 2015)involving 28 research institutes and private companies.Three complementary approaches were pursued:(i)tool and software development,(ii)deciphering genetic control of main horticultural traits taking into account allelic diversity and(iii)developing plant materials,tools and methodologies for breeders.Decisive breakthroughs were made including the making available of ready-to-go DNA diagnostic tests for Marker Assisted Breeding,development of new,dense SNP arrays in apple and peach,new phenotypic methods for some complex traits,software for gene/QTL discovery on breeding germplasm via Pedigree Based Analysis(PBA).This resulted in the discovery of highly predictive molecular markers for traits of horticultural interest via PBA and via Genome Wide Association Studies(GWAS)on several European genebank collections.FruitBreedomics also developed pre-breeding plant materials in which multiple sources of resistance were pyramided and software that can support breeders in their selection activities.Through FruitBreedomics,significant progresses were made in the field of apple and peach breeding,genetics,genomics and bioinformatics of which advantage will be made by breeders,germplasm curators and scientists.A major part of the data collected during the project has been stored in the FruitBreedomics database and has been made available to the public.This review covers the scientific discoveries made in this major endeavour,and perspective in the apple and peach breeding and genomics in Europe and beyond.

From Monoculture to Norfolk System: How the Number of Crops in Rotation Can Influence the Biodiversity of Arbuscular Mycorrhiza Assemblages in the Soil

Given the attention drawn since several decades by arbuscular mycorrhizal fungi (AMF) as potential biological alternatives to chemicals in a low-input agriculture, much effort has been spent in the investigation of mechanisms influencing the dynamics inside AMF communities. In the present study we evaluated the influence of different crop rotations on the AMF soil community, after a 50 y long-term field experiment established at Martonvásár, Hungary. Four types of crop rotation were chosen for sampling: corn monocropping, corn-alfalfa, corn-wheat, and corn-spring barley-peas-wheat. Community composition of AMF in soil was analyzed with a molecular approach amplifying a portion of 28S rDNA. The crop rotation practice didn’t show an influence on identity of the species composing AMF assemblages, but on the other hand seemed to affect positively the true diversity, defined as number of MOTUs present in the communities.

A Simplified Method to Estimate the Time Evolution of Oil Extraction from Different Substrates by Supercritical CO₂

To allow an easy individuation of the more suitable working conditions (temperature, pressure, flow rate, etc.) to be adopted to carry out the extraction of food grade oils from different substrates by supercritical CO2 (Sc-CO2), a simpli- fied kinetic approach has been introduced. This kinetic model was utilised to describe supercritical fluid extraction (SFE) of oil by Sc-CO2 not only from seeds (sunflower, soybean and rape) but also from microalgae (Nannochloropsis sp., Schizochytrium sp. and Spirulina (Arthrospira) platensis) characterised by a lipid fraction with a high proportion of polyunsatured fatty acids (C20:5w-3;C22:6w-3;C18:3w-6). Thanks to the high affinity occurring between oil and Sc-CO2 it was possible to introduce a simplified kinetic model able to describe the time evolution of oil extraction from substrates which deeply differ for biochemical and biophysical characteristics. Moreover the synergistic utilisation of the kinetic model introduced and of the Chrastil’s equation, allowed to predict the time evolution of oil extraction as a function of the: substrate used;amount of its fat content;mass of substrate charged inside the extractor;possible pre- treatments carried out on the used substrate;flow rate of Sc-CO2;working conditions adopted (temperature, pressure and then Sc-CO2 density).

Urban Forest Digital Cadastre

Urban forests being part of the Natural Capital,they provide goods and services for humans,the ecosystem services that are necessary for their survival.Over recent years,the importance of ecosystem services within urban landscapes has grown steadily.Determining the amount and the value of the ecosystem services provided by the Urban Forest is the main goal of the“Digital Green Cadastre”(DGC),a project in progress of survey,classification and mapping of the urban,agricultural and natural green assets.The DGC records the types of green cover and soil characteristics and utilizes the calculation of the total leaf area for the quantitative analysis of the botanical heritage,environmental performance and ecosystem benefits,such as water runoff management,air pollutant removal and urban heat island reduction.The case study of Abbiategrasso-a small town in Italy-is reported.

QTL analysis for ascorbic acid content in strawberry fruit reveals a complex genetic architecture and association with GDP-L-galactose phosphorylase

Strawberry(Fragaria×ananassa)fruits are an excellent source of L-ascorbic acid(AsA),a powerful antioxidant for plants and humans.Identifying the genetic components underlying AsA accumulation is crucial for enhancing strawberry nutritional quality.Here,we unravel the genetic architecture of AsA accumulation using an F1 population derived from parental lines‘Candonga’and‘Senga Sengana’,adapted to distinct Southern and Northern European areas.To account for environmental effects,the F1 and parental lines were grown and phenotyped in five locations across Europe(France,Germany,Italy,Poland and Spain).Fruit AsA content displayed normal distribution typical of quantitative traits and ranged five-fold,with significant differences among genotypes and environments.AsA content in each country and the average in all of them was used in combination with 6,974 markers for quantitative trait locus(QTL)analysis.Environmentally stable QTLs for AsA content were detected in linkage group(LG)3A,LG 5A,LG 5B,LG 6B and LG 7C.Candidate genes were identified within stable QTL intervals and expression analysis in lines with contrasting AsA content suggested that GDP-L-Galactose Phosphorylase FaGGP(3A),and the chloroplast-located AsA transporter gene FaPHT4;4(7C)might be the underlying genetic factors for QTLs on LG 3A and 7C,respectively.We show that recessive alleles of FaGGP(3A)inherited from both parental lines increase fruit AsA content.Furthermore,expression of FaGGP(3A)was two-fold higher in lines with high AsA.Markers here identified represent a useful resource for efficient selection of new strawberry cultivars with increased AsA content.

Climatic and anthropogenic factors explain the variability of Fagus sylvatica treeline elevation in fifteen mountain groups across the Apennines

Background:Fagus sylvatica forms the treeline across the Apennines mountain range,with an average elevation of 1589 ma.s.l.Previous studies evidenced that the current position of the treeline in the Apennines is heavily depressed as a result of a complex interaction between climatic factors and the past human pressure.In this study we correlated treeline elevation in the fifteen major mountain groups in the Apennines with selected climatic,geomorphological,and human disturbance variables in order to investigate in detail the site-specific features affecting the current treeline distribution.Results:Treeline elevation was lowest in the North Italy(Apuan Alps),while the highest treeline was found in Central Italy(Simbruini).An absolute maximum treeline elevation of F.sylvatica exceeding 2000ma.s.l.was found on 13 mountain peaks in Central and Southern Italy.Noteworthy,treeline elevation was largely lower on warmer south-facing slopes compared to northern slopes,with values several hundred meters lower in the Gran Sasso and Velino-Sirente.Although the causes of this pattern are still unknown,we argue that treeline elevation on southfacing slopes may be limited by the combination of climatic constraints(i.e.summer drought)and human disturbance.Evidence of a pervasive anthropogenic effect depressing treeline elevation was found in the North(Apuan Alps)Central(Gran Sasso,Velino-Sirente,Sibillini)and Southern part of Apennines(Pollino).By contrast,treeline elevation of the Laga,Simbruini,and Orsomarso mountain groups appears less affected by past anthropogenic disturbance.Finally,we recorded in the several mountain groups(i.e.Majella,Marsicani and Pollino)the coexistence of very depressed treelines just a few kilometers away from much higher treelines,among the highest ever recorded for F.sylvatica.Conclusions:Finally,we argue that F.sylvatica treeline across the Apennines is locally shaped both by the interaction of low temperatures experienced by the species in its earliest life stages in snow-free open spaces with summer soil water depletion and human disturbance.

Relationship between apoptotic markers in semen from fertile men and demographic, hormonal and seminal characteristics

Apoptosis in the testis has two putative roles during normal spermatogenesis; limitation of the germ cell population to numbers that can be supported by the Sertoli cells, and, possibly, selective depletion of meiotic and postmeiotic abnormal germ cells. We investigated the demographic and biological correlates of the pro-apoptotic marker Fas and the anti-apoptotic marker Bcl-xL in sperm cells of fertile men. Six hundred and four men from Greenland, Poland and Ukraine were consecutively enrolled during their pregnant wife＇s antenatal visits. Semen analysis was performed as recommended by the World Health Organization. Immunofluorescence coupled to flow cytometry was utilized for detection of apoptotic markers in the sperm cell. DNA damage was assessed by flow cytometry using both the sperm chromatin structure assay （SCSA） and the terminal deoxynucleotidyl transferase dUTP nick end labelling （TUNEL） assay. The percentage of Fas-positive sperm cells was higher in men with high total sperm count （P〈O.01）, more motile sperms （P=-O.04） and fewer sperm head defects （P=-O.05）. These associations were consistent within and across study regions. Furthermore, testosterone, follicle-stimulating hormone （FSH） and sexual hormone-binding globulin （SHBG） were significantly negatively correlated with Fas within and across regions as well. The data indicated no association between the anti-apoptotic Bcl-xL marker and semen or personal characteristics. The finding of Fas-positive sperm cells associated with better semen quality in a cohort of spouses of pregnant women seems different from previous data obtained in infertile men and warrants further investigation to clarify the biological significance of sperm apoptotic markers.

Combined forest and soil management after a catastrophic event

At the end of October 2018,a storm of unprecedented strength severely damaged the forests of the eastern sector of the Italian Alps.The affected forest area covers 42,500 ha.The president of one of the damaged regions asked for help from the University of Padua.After eight months of discussion,the authors of this article wrote a consensus text.The sometimes asper debate brought to light some crucial aspects:1)even experienced specialists may have various opinions based on scientific knowledge that lead to conflicting proposals for action.For some of them there is evidence that to restore a destroyed natural environment it is more judicious to do nothing;2)the soil corresponds to a living structure and every ecosystem’s management should be based on it;3)faced with a catastrophe,people and politicians find themselves unarmed,also because they rarely have the scientific background to understand natural processes.Yet politicians are the only persons who make the key decisions that drive the economy in play and therefore determine the near future of our planet.This article is an attempt to respond directly to the governor of a region who formally and prudently asked a university department called"Land,Environment,Agriculture and Forestry"for help before taking decisions;4)the authors also propose an artistic interpretation of facts(uncontrolled storm)and conclusions(listen to the soil).Briefly,the authors identify the soil as an indispensable source for the renewal of the destroyed forest,give indications on how to prepare a map of the soils of the damaged region,and suggest to anchor on this soil map a series of silvicultural and soil management actions that will promote the soil conservation and the faster recovery of the natural dynamic stability and resilience.

Effect of the rearing diet on gene expression of antimicrobial peptides in Hermetia illucens(Diptera:Stratiomyidae)

Insect proteins have been proposed for human and animal food production.Safeguarding the health status of insects in mass rearing allows to obtain high-quality products and to avoid severe economic losses due to entomopathogens.Therefore,new strategies for preserving insect health must be implemented.Modulation of the insect im-mune system through the diet is one such strategy.We evaluated gene expression of two antimicrobial peptides(one defensin and one cecropin)in Hermetia illucens(L.)(Diptera:Stratiomyidae)reared on different diets.Analyses were performed on prepupae and 10-day-old larvae reared on cereal-and municipal organic waste-based diets and on only prepupae reared on a cereal-based diet supplemented with sunflower,corn,or soybean oil.The inclusion of sunflower oil at different points in the cereal-based diet was also evalu-ated.Moreover,diet-driven differences in the inhibitory activity of the hemolymph were tested against Escherichia coli DH5αand Micrococcus yunnanensis HI55 using diffusion assays in solid media.Results showed that a municipal organic waste-based diet produced a significant overexpression of antimicrobial peptides only in prepupae.Inclusion of veg-etable oils caused an upregulation of at least one peptide,except for the corn oil.Higher expression of both genes was observed when sunflower oil was added 5 days before pupa-tion.All hemolymph samples showed an inhibitory activity against bacteria colonies.Our results suggest that municipal organic waste-based diet and vegetable oil-added diet may successfully impact the immune system of H.illucens.Such alternatives may also exist forotherspeciesofeconomic interest.

家禽红螨(鸡皮刺螨)的意义及防治

家禽红螨(鸡皮刺螨)严重威胁世界各地的家禽生产和母鸡健康。鸡皮刺螨不但逐渐被认为是疫病重要的载体,而且有越来越多的报告显示其还可攻击包括人类在内的其他宿主,可见这种害虫对经济的影响变得越来越严重。随着世界各地的家禽生产逐渐脱离传统的笼养方式,鸡皮刺螨在禽群中的影响将变得更加普遍,防控将变得更加困难。尽管已有耐药性和治疗失败的报告,但鸡皮刺螨的防治仍以合成杀螨剂为主。目前在鸡皮刺螨及螨虫管理的专项研究报告中已经提出一些替代防治措施。尽管许多替代防治措施仍处于商业化前期阶段,但仍有部分措施已经逐渐进入市场。本综述汇集了日益扩充的鸡皮刺螨的研究,并评估了其当前和未来可供选择的防控措施。得出的结论是,鸡皮刺螨防治的重大进展最有可能来自综合防控的措施,将最新的研究融入到现有的和新型的防治策略中,这种融合将改进的监测和建模相结合,更好地为治疗和干预该病提供信息支持。

Metamicrobiomics in herbivore beetles of the genus Cryptocephalus （Chrysomelidae）： toward the understanding of ecological determinants in insect symbiosis

The Cryptocephalus marginellus （Coleoptera： Chrysomelidae） complex is composed by six species that are supposed to have originated by events of allo- or parapatric speciation. In the present study we investigated the altemative hypotheses that the bacterial communities associated with six populations of this species complex are shaped by environmental factors, or reflect the proposed pattern of speciation. The microbiota associated with the six populations, from five species of the complex, have been characterized through 16S rRNA pyrotag sequencing. Based on a 97% sequence similarity threshold, data were clustered into 381 OTUs, which were analyzed using a variety of diversity indices. The microbiota of C. acquitanus and C. marginellus （Calanques） were the most diverse （over 100 OTUs）, while that from C. zoiai yielded less bacterial diversity （45 OTUs）. Taxonomic assignment revealed Proteobacteria, Tenericutes and Firmicutes as the dominant components of these beetles＇ microbiota. The most abtmdant genera were Ralstonia, Sphingomonas, Rickettsia, and Pseudomonas. Different strains of Rickettsia were detected in C. eridani and C. renatae. The analysis of β-diversity revealed high OTU turnover among the populations of C. marginellus complex, with only few shared species. Hierarchical clustering taking into account relative abundances of OTUs does not match the phylogeny of the beetles, therefore we hypothesize that factors other than phylogenetic constraints play a role in shaping the insects＇ microbiota. Environmental factors that could potentially affect the composition of bacterial communities were tested by fitting them on the results of a multi-dimensional scaling analysis. No significant correlations were observed towards the geographic distances or the host plants, while the composition of the microbiota appeared associated with altitude. The metabolic profiles of the microbiotas associated with each population were inferred from bacterial taxonomy, and interestingly, the obtained clustering pattern was consistent with the host phylogeny.

Evaluation of dietary addition of 2 essential oils from Achillea moschata,or their components (bornyl acetate,camphor,and eucalyptol) on in vitro ruminal fermentation and microbial community composition

This study investigated the effects of 2 Achillea moschata essential oils extracted from plants collected in 2 different valleys of the Italian Alps and 3 pure compounds of oils—bornyl acetate(BOR),camphor(CAM),and eucalyptol(EUCA)—on in vitro ruminal fermentation and microbiota.An in vitro batch fermentation experiment(Exp.1)tested the addition of all of the substances(2 essential oils and 3 compounds)in fermentation bottles(120 mL)at 48 h of incubation,whereas a subsequent in vitro continuous culture experiment(Exp.2)evaluated the pure compounds added to the fermenters(2 L)for a longer incubation period(9 d).In both experiments,total mixed rations were incubated with the additives,and samples without additives were included as the control(CTR).Each treatment was tested in duplicate and was repeated in 3 and 2 fermentation runs in Exp.1 and 2,respectively.Gas production(GP)in Exp.1 was similar for all of the treatments,and short chain volatile fatty acid(SCFA)production was similar in both experiments except for a decrease of SCFA produced(P=0.029)due to EUCA addition in Exp.2.Compared to CTR,BOR and CAM reduced the valerate proportion(P=0.04)in Exp.1,and increased(P<0.01)the acetate proportion in Exp.2.All treatments increased(P<0.01)total protozoa counts(+36.7%and+48.4%compared to CTR on average for Exp.1 and 2,respectively).In Exp.1,all of the treatments lowered the Bacteroidetes and Firmicutes and increased the Proteobacteria relative abundances(P<0.05),whereas in Exp.2,the EUCA addition increased(P=0.012)the Ruminococcus.In Exp.1,methane(CH4)as a proportion of the GP was lowered(P=0.004)by the addition of CAM and EUCA compared to CTR,whereas in Exp.2,EUCA reduced the amount of stoichiometrically calculated CH4 compared to CTR.Overall,essential oils extracted from A.moschata and the pure compounds did not depress in vitro rumen fermentation,except for EUCA in Exp.2.In both experiments,an increase of the protozoal population occurred for all the additives.

Evidence for a con served microbiota across the different developmental stages of Plodia interpunctella

Diversity and composition of lepidopteran microbiotas are poorly investigated, especially across the different developmental stages. To improve this knowledge, we characterize the microbiota among different developmental stages of the Indian meal moth, Plodia interpunctella, which is considered one of the major pest of commodities world-wide. Using culture-independent approach based on Illumina 16S rRNA gene sequencing we characterized the microbiota of four developmental stages: eggs, first-, and last-instar larvae, and adult. A total of 1022 bacterial OTUs were obtained, showing a quite diversified microbiota associated to all the analyzed stages. The microbiotas associated with P. interpunctella resulted almost constant throughout the developmental stages, with approximately 77% of bacterial OTUs belonging to the phylum of Proteobacteria. The dominant bacterial genus is represented by Burkholderia (?64%), followed by Propionibacterium, Delftia, Pseudomonas, and Stenotrophomonas. A core bacterial community, composed of 139 OTUs, was detected in all the developmental stages, among which 112 OTUs were assigned to the genus Burkholderia. A phylogenetic reconstruction, based on the 16S rRNA, revealed that our Burkholderia OTUs clustered with Burkholderia cepacia complex, in the same group of those isolated from the hemipterans Gossyparia spuria and Acanthococcus aceris. The functional profiling, predicted on the base of the bacterial 16S rRNA, indicates differences in the metabolic pathways related to metabolism of amino acids between preimaginal and adult stages. We can hypothesize that bacteria may support the insect host during preimaginal stages.

Evaluation of the potential exposure of butterflies to genetically modified maize pollen in protected areas in Italy

Environmental impacts of genetically modified crops are mandatorily assessed during their premarket phase. One of the areas of concern is the possible impact on nontar- get organisms. Crops expressing Cry toxins might affect Lepidoptera larvae living outside cultivated fields, through pollen deposition on wild plants, which constitute their food source. While pollen toxicity varies among different events, possible exposure ofnontarget species depends on the agro-environmental conditions. This study was conducted in two protected areas in Italy, characterized by different climatic conditions, where many Lepi- doptera species thrive in proximity to maize cultivations. To estimate the possible exposure in absence of the actual stressor （e.g., Cryl-expressing maize plants）, we conducted a two-year field survey of butterflies and weeds. Indicator species were selected--Aglais （Inachis） io in the Northern site and Vanessa cardui in the Southern site--and their phe- nology was investigated. Pollen dispersal from maize fields was measured by collection in Petri dishes. Duration and frequency of exposure was defined by the overlap between pollen emission and presence of larvae on host plants. Different risk scenarios are expected in the two regions： highest exposure is foreseen forA. io in the Northern site, while minimal exposure is estimated for V. cardui in the Southern site. In the latter case, locally grown maize cultivars flower in mid-summer in coincidence with an aestivation period for several butterfly species due to hot and dry conditions. Moreover, host plants of V. cardui are at the end of their life cycle thus limiting food availability.

The omnivorous predator Macrolophus pygmaeus,a good candidate for the control of both greenhouse whitefly and poinsettia thrips on gerbera plants

The poinsettia thrips Echinothrips americanus Morgan is a relatively new pest that has spread rapidly worldwide and causes serious damage in both vegetable and ornamental plants.In this study,we investigated if and how effective this pest can be controlled in gerbera by the omnivorous predator Macrolophus pygmaeus(Rambur).Because herbivores on plants can interact through a shared predator,we also investigated how poinsettia thrips control is affected by the presence of the greenhouse whitefly Trialeurodes vaporariorum(Westwood),a pest that commonly coexists with E.americanus in gerbera.In laboratory studies,we found that the predator M.pygmaeus fed on both pests when offered together.Olfactometer tests showed a clear preference of the predators for plants infested by whiteflies but not by thrips.In a greenhouse experiment,densities of both pests on single gerbera plants were reduced to very low levels by the predator,either with both pests present together or alone.Hence,predator‐mediated effects between whiteflies and thrips played only a minor role.The plant feeding of the shared predator probably reduced the dependence of predator survival and reproduction on the densities of the two pests,thereby weakening potential predator‐mediated effects.Thus,M.pygmaeus is a good candidate for biological control of both pests in gerbera.However,further research is needed to investigate pest control at larger scales,when the pests can occur on different plants.

Predicted and measured soil retention curve parameters in Lombardy region north of Italy

Water retention characteristics are fundamental input parameters in any modeling study on water flow and solute transport.These properties are difficult to measure and for that reason,we usually need to use direct and indirect methods to determine them.An extensive comparison between measured and estimated results is needed to determine their applicability for a range of different soils.However this study attempts to make a contribution specifically in this connection.These properties were determined in two representative sites located in Landriano field,in Lombardy region,northern Italy.In the laboratory we used the pressure plate apparatus and the tensiometric box.Field soil water retention was determined including measurements of soil water content with SENTEK probes and matric potential with tensiometers.The soil waer retention curves(SWRC)were also settled on with some recently developed pedo-transfert functions(PTFs).Field retention curves were compared against those obtained from PTFs estimations and laboratory measurements.The comparison showed that laboratory measurements were the most accurate.They had the highest ranking for the validation indices(RMSE ranging between 2.4%and 7.7%and bias between 0.1%and 6.4%).The second best technique was the PTF Rosetta(Schaap et al.2001).They perform only slightly poorer than the laboratory measurements(RMSE ranging between 2.7%and 10%and bias between 0.3%and 7.7%).The lowest prediction accuracy is observed for the Rawls and Brakensiek(1985)PTF(RMSE ranging between 6.3%and 17%and bias between 5%and 10%)which is in contradiction with previous finding(Calzolari et al.,2001),showing that this function is well representing the retention characteristics of the area.Due to time and cost investments of laboratory and field measurements,we conclude that the Rosetta PTF developed by Schaap et al.(2001)appears to be the best to predict the soil moisture retention curve from easily available soil properties in the Lombardy area and further field investigations would be useful to support this finding.

Box Behnken design-based optimized extraction of non-dioxin-like PCBs for GC-ECD and GC-MS analyses in milk samples

A multivariate optimization process of the sample extraction procedure by Box-Behnken design through a global desirability function is described for the determination of six non-dioxin-like polychlorinated biphenyls(NDL-PCBs#28,52,101,153,138 and 180)in milk by GC-ECD and mass spectrometry.Three factors were involved in refining the extraction conditions:the acetone percentage in the extraction mixture,the sample/solvent ratio,and the extraction time.The three-factor design required 26 experiments that were carried out in duplicate and in a randomized order to minimize the bias effects of uncontrolled variables.The optimized factors(acetone percentage:30%;sample-to-solvent ratio:0.11 g mL^-1;extraction time:45 min)ensured a low solvent consumption and a reduced extraction time,allowing a rapid and simultaneous preparation of multiple sample extracts.The method was validated according to the European directives(Decision 657/2002/EC,SANTE 2017/11813/EC)through the evaluation of linearity,selectivity,LOD,LOQ,recovery,precision,and ruggedness.

Alternate Wetting and Drying of Rice Reduced CH4 Emissions but Triggered N2O Peaks in a Clayey Soil of Central Italy

Reducing CH_4 and N_2O emissions from rice cropping systems while sustaining production levels with less water requires a better understanding of the key processes involved. Alternate wetting and drying(AWD) irrigation is one promising practice that has been shown to reduce CH_4 emissions. However, little is known about the impact of this practice on N_2O emissions, in particular under Mediterranean climate. To close this knowledge gap, we assessed how AWD influenced grain yield, fluxes and annual budgets of CH_4 and N_2O emissions, and global warming potential(GWP) in Italian rice systems over a 2-year period. Overall, a larger GWP was observed under AWD, as a result of high N_2O emissions which offset reductions in CH_4 emissions. In the first year, with 70% water reduction, the yields were reduced by 33%, CH_4 emissions decreased by 97%, while N_2O emissions increased by more than 5-fold under AWD as compared to PF; in the second year, with a 40% water saving, the reductions of rice yields and CH_4 emissions(13% and11%, respectively) were not significant, but N_2O fluxes more than doubled. The transition from anaerobic to aerobic soil conditions resulted in the highest N_2O fluxes under AWD. The duration of flooding, transition to aerobic conditions, water level above the soil surface, and the relative timing between fertilization and flooding were the main drivers affecting greenhouse gas mitigation potential under AWD and should be carefully planned through site-specific management options.

Mapping and ultrastructure of antennal chemosensilla of the wheat bug Eurygaster maura

Antennae of the wheat stink bug Eurygaster maura L. （Hemiptera： Scutelleridae） were investigated to elucidate structure and distribution of antennal chemosensilla in females. Five type of sensilla were identified and characterized using a scanning electron microscope （SEM） and a transmission electron microscope （TEM）. Type 1 sensilla are mechanical and contact chemoreceptors with a single apical pore. Types 2 and 3 sensilla are multiporous chemoreceptors both with typical features of olfactory sensilla. Type 4 are multiporous peg-like sensilla, short and with a grooved surface. Type 5 are sensilla coeloconica with a smooth and aporous peg completely inserted in a sub-cuticular chamber. All types are distributed on the two flagellar segments, but we considered only the apical flagellomere in which the largest number of sensilla are located. The most abundant sensilla are type 3, while the less numerous are type 5. All types, except type 2, decreased in number from the tip to the base of the segment. The lower density of sensilla was recorded on the dorsal-internal part of the apical antennomere, while the higher density was recorded on the opposite side （external-ventral）.

Soil Physical Quality of Citrus Orchards Under Tillage, Herbicide, and Organic Managements

Soil capacity to support life and to produce economic goods and services is strongly linked to the maintenance of good soil physical quality(SPQ). In this study, the SPQ of citrus orchards was assessed under three different soil managements, namely no-tillage using herbicides, tillage under chemical farming, and no-tillage under organic farming. Commonly used indicators, such as soil bulk density,organic carbon content, and structural stability index, were considered in conjunction with capacitive indicators estimated by the Beerkan estimation of soil transfer parameter(BEST) method. The measurements taken at the L'Alcoleja Experimental Station in Spain yielded optimal values for soil bulk density and organic carbon content in 100% and 70% of cases for organic farming. The values of structural stability index indicated that the soil was stable in 90% of cases. Differences between the soil management practices were particularly clear in terms of plant-available water capacity and saturated hydraulic conductivity. Under organic farming, the soil had the greatest ability to store and provide water to plant roots, and to quickly drain excess water and facilitate root proliferation.Management practices adopted under organic farming(such as vegetation cover between the trees, chipping after pruning, and spreading the chips on the soil surface) improved the SPQ. Conversely, the conventional management strategies unequivocally led to soil degradation owing to the loss of organic matter, soil compaction, and reduced structural stability. The results in this study show that organic farming has a clear positive impact on the SPQ, suggesting that tillage and herbicide treatments should be avoided.