Alternative Host Research Articles

Insect Vector and Reservoir Plant of 'Fragaria × ananassa' Phyllody Phytoplasma (16SrXIII-F) in Central Region of Chile.

Strawberry phyllody has emerged as a prevalent disease affecting Chilean strawberry in recent years. The causal pathogen, 'Fragaria × ananassa' phyllody phytoplasma (StrPh), is categorized within the 16S ribosomal group XIII that is exclusively found in the Americas. In the context of economically significant crops, hemipteran insect vectors and alternative host plants play a pivotal role in their natural dissemination. This study comprehensively examined the key epidemiological facets of StrPh in the central region of Chile: the insect vector and alternative hosts. Through field surveys, we identified an abundance of an insect species, Cixiosoma sp., in an StrPh-infected strawberry field and confirmed its role as a vector of this phytoplasma through subsequent transmission assays. Moreover, we found a spontaneous weed species, Galega officinalis, to be infected with StrPh, raising the possibility of it being a potential alternative host plant for this phytoplasma. StrPh was also detected in cold-stored strawberry runners purchased from a nursery that supplies the local strawberry cultivation, suggesting a potential source of this phytoplasma in Chile. Collectively, these findings provide a significant epidemiological source of StrPh dissemination in central Chile.

First report of rust caused by Gymnosporangium in Iceland.

Sorbus is a genus of trees and shrubs in the Rosaceae commonly known as rowan and mountain-ash. They are usually found in temperate regions of the Northern Hemisphere and cultivated as ornamental trees for parks and gardens. In September 2023, infection by a rust was observed on a single Sorbus aucuparia tree in Sólbrekkuskógur, Reykjanesbær (64.046645, -22.707276; ~13 m) in Iceland. Infected leaves were collected from this single cultivated tree at an outdoor recreation area in a natural wooded location, with a 2% disease severity. Sori were infrequent, scattered, embedded within circular yellow lesions on leaf margins. On average, one sorus was observed per leaf and only 2% of leaves were infected. Spermogonia epiphyllous, punctate and aggregated, pale yellow to black. Hypophyllous aecia roestelioid with cornute peridium rupturing at apex with peridial cells rhomboidal, aeciospores yellowish brown globoid 17.67-25.17 x 17.20-21.94 µm, walls 1.22-2.28 µm thick (n = 20). The features of this rust and dimensions of spores are consistent with descriptions of Gymnosporangium cornutum (Arthur 1909, Kern 1911). To confirm the identity (specimen MCA9732), a ~620 bp region of the 28S subunit of the ribosomal DNA repeat was sequenced using primers Rust2inv and LR6 following published protocols (Aime 2006). The sequence (GenBank PP413765) shared 100% (649/649 bp) identity with a sequence deposited as Gymnosporangium cornutum (KY764066, BPI910184; J. E. Demers, M. K. Romberg, and L. A. Castlebury, unpublished data) from S. americana and 100% (620/620 bp) identity with G. cornutum (PURN11049) on Sorbus sp. from Canada when blasted against the RustHUBB database (Kaishian et al. 2024). The specimen has been deposited in the Arthur Fungarium at Purdue University as PURN24233. Disease on Sorbus sp. caused by G. cornutum has been reported in various countries in Africa, Asia, North America, and Europe (Kern 1911). To our knowledge, this is the first report of the occurrence of this genus in Iceland from any host. Gymnosporangium cornutum alternates on Juniperus species. In Iceland, J. communis (sect. Oxycedrus) seems to be the only naturally occurring Juniperus species but it is an alternate host for G. cornutum. The presence of the primary and alternative hosts in Iceland and the ability of Gymnosporangium spp. to produce systemic infections in Juniperus spp., represents the potential for reinfection of Sorbus every year, resulting in potential impacts on both host species. With J. communis being the only Juniperus spp. in natural habitats in Iceland, the presence of this rust represents a potential ecological disruption, as repeated infections may reduce host vitality and predispose the host to winter injury and attack from opportunistic pathogens or insects.

Community structure of parasitoids attacking Schizomyia sasakii (Diptera: Cecidomyiidae) and local adaptation of the gall midge in the Izu region

AbstractInsect community structures and biological interactions vary with the distance from the mainland to islands. Gall inducers are key organisms in local arthropod communities because their galls harbor diverse arthropods. We investigated the parasitoid community of a gall‐inducing cecidomyiid Schizomyia sasakii on the Izu Peninsula and the Izu Islands, Japan. We examined relationships between parasitism by Inostemma sp. and Torymus hirtipennis, and gall characteristics, and analyzed the directional selection on gall characteristics induced by S. sasakii in each locality. The species richness of parasitoids on the Izu Islands decreased with the distance from the Izu Peninsula to each island, and area of respective islands. Inostemma sp. preferably attacked large galls on Ohshima Island, and T. hirtipennis tended to attack relatively small galls in the Izu Peninsula. Directional selection on gall characteristics of S. sasakii favored the induction of larger galls and thicker tissues by S. sasakii on Ohshima Island. In contrast, no directional selection was detected in the gall characteristics on Hachijojima Island. The number of alternative host species of parasitoid may affect variation in parasitoid richness of S. sasakii on distant and small islands, because the species richness of gall midges is necessary to maintain local parasitoid populations. Our study supported the ovipositor limitation hypothesis for the torymid species, related to gall size. The directional selection of parasitoid attacks on the Izu Islands may act to favor the induction of large and hypertrophic galls by S. sasakii to avoid the parasitoids.

Survey of tenuipalpid mites (Acariformes: Tenuipalpidae) in orchid species with the presence of Cilevirus in Colombia

To understand and manage viruses causing citrus leprosis it is necessary to identify their alternate host plants and know their distributions. Currently, the citrus leprosis disease is associated with several viruses of the genera Cilevirus and Dichoravirus. In Colombia, symptoms of citrus leprosis have been related to citrus leprosis virus C (CiLV-C - Cilevirus leprosis) and citrus leprosis virus C2 (CiLV-C2 - Cilevirus colombiaense). To detect leprosis-associated viruses in plants of the family Orchidaceae and identify the possible associated vectors, inspections and samplings were carried out on garden plants and orchid crops, and molecular detection of viruses and the taxonomic identification of mites were accomplished. As a result, Brevipalpus californicus s. l., B. phoenicis s.s., and B. essigi (Prostigmata: Tenuipalpidae) are recorded for the first time on orchid plants from Colombia. A taxonomic key is provided to identify mites of the family Tenuipalpidae on orchids worldwide. The implications of these mites for the phytosanitary protection in citrus crops of Colombia are discussed.

High Diversity of Curtobacterium flaccumfaciens in Poinsettia and Detection of Three Pathogenicity Plasmids for Identification of C. flaccumfaciens pv. poinsettiae

Outbreaks in Europe have raised concerns about poinsettia bacterial canker caused by Curtobacterium flaccumfaciens pv. poinsettiae, described in the United States. Using a semiselective medium containing aztreonam and fosfomycin and selection during isolation based on matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) spectra, 424 Curtobacterium strains were isolated from Belgian poinsettias of African and European origin. Different populations coexisted: 130 strains were identified as C. flaccumfaciens with scores ≥2.0 and 294 with scores <2.0 or as another Curtobacterium. MALDI-TOF MS libraries constructed using similar medium and extraction procedure and a pathogenicity test on poinsettia were used to screen collections from poinsettia and wheat, a possible alternative host, for C. flaccumfaciens pv. poinsettiae. The concatenated recA- gyrB partial sequences showed that 114 poinsettia or wheat strains belonged to different Curtobacterium species. Eighty-eight nonpathogenic strains and four U.S. strains from litter were intermingled with bean pathogenic C. flaccumfaciens pv. flaccumfaciens strains in the three genetic groups of C. flaccumfaciens but lacked their pathogenicity markers. Four new European recA- gyrB sequatypes of C. flaccumfaciens pv. poinsettiae, obtained from symptomatic and asymptomatic poinsettias, were distinguished from three American sequatypes. Six sequatypes were pathogenic in tests, belonged to genetic groups related to two different genomospecies, and possessed a plasmid. Sequencing of six plasmids revealed three related plasmids containing proteases and a polygalacturonase found only in strains pathogenic in pathogenicity tests and specifically identified by polygalacturonase-based PCR and loop-mediated isothermal amplification assays. Similarities between plant and litter Curtobacterium and the role of plasmids in pathogenicity and punctual transmission of pathogenicity among heterogeneous C. flaccumfaciens are suggested.

Effects of Antheraea pernyi on Parasitization of Kriechbaumerella dendrolimi by Using Immunology and Metabolomics

Kriechbaumerella dendrolimi (Hymenoptera, Chalcididae) is a dominant pupal parasitoid species of various significant pine caterpillars, including Dendrolimus houi Lajonquiere (Lepidoptera, Lasiocampidae), with great potential for utilization. So far, the mass rearing of K. dendrolimi has been successfully established using Antheraea pernyi (Lepidoptera, Saturniidae) pupae as alternative hosts and released in the forest to suppress D. houi populations. However, the outcome is still expected to be improved due to lower parasitism rates, which might be related to the autonomous immune function of A. pernyi pupae. In our study, we investigated the effects of K. dendrolimi parasitization on the immune responses of A. pernyi pupae by measuring the expression of key immune factors: superoxide dismutase (SOD), polyphenol oxidases (PPOs), Attacin, Lysozymes (LYSs), and serine proteases (PRSSs). Our results show that parasitization significantly upregulated these immune factors, with distinct temporal patterns observable between 4 and 48 h post-parasitization. This upregulation highlights a robust immune response, adapting over time to the parasitic challenge. These findings suggest that specific immune mechanisms in A. pernyi pupae are activated in response to K. dendrolimi, shedding light on potential targets for enhancing host resistance. Metabolomic analyses complemented these findings by illustrating the broader metabolic shifts associated with the immune response. Specifically, Attacin was significantly upregulated twice, hypothesizing that the parasitoid’s venom contains at least two parasitic factors. Metabolomics analysis revealed a significant metabolite difference within parasitized A. pernyi pupae. The highest number of differential expression metabolites (DEMs) was observed at 16 h post-parasitism (1184 metabolites), with fewer DEMs at 8 h (568 metabolites) and 32 h (693 metabolites), suggesting a close relationship between parasitism duration and the number of DEMs. These fluctuations reflected the fundamental process of immune interaction. KEGG enrichment results showed that the DEMs were mainly enriched in energy metabolism and immune-related pathways, indicating that parasitism is a process of continuous consumption and immune interaction in the host. These DEMs could also become future targets for regulating the immune functions of A. pernyi pupae and could provide reference data for optimizing mass-rearing techniques.

Ontogeny and phylogeny of the genus Solus Watson, 1913 (Lepidoptera: Saturniidae)

Abstract Preimaginal stages of the enigmatic genus Solus Watson, 1913 are described for the first time, based on a completed life history of a representative species Solus parvifenestratus Bryk, 1944 fed with Camphora officinarum, with a report on testing of alternative potential host plants. The complete mitochondrial genomes are produced for two species within the genus and they are used to construct phylogenetic hypothesis and analyze nucleotide diversity. The alternative hypotheses derived from the molecular analyses are discussed in light of 14 morphological and biological features, the optimal result supports Solus to be the sister group of Saturniini + Attacini and justifies the establishment of the tribe Solini within the subfamily Saturniinae.

Understanding life cycle of parasitic weed Phelipanche ramosa infesting Brassica juncea in India: new host species and seed coat structure

ABSTRACT Broomrape (Phelipanche ramosa) is an obligate root parasitic plant that is known to infest many important crops. It is emerging as a serious biotic threat for Brassica juncea cultivation in India. There is very limited information available about broomrape species and its infestation in B. juncea. Hence, the present study encompassed a comprehensive five-year field survey spanning from 2018 to 2023 of 47 different B. juncea fields in the states of Rajasthan and Haryana in India. The level of broomrape infestation varied from season to season and field to field. In the B. juncea fields, broomrape with blue/violet color corolla, along with occasionally white color type were also noticed. The hairy anther, corolla shape and use of mitochondrial DNA-specific molecular markers revealed that both these broomrape types belong to Phelipanche ramosa. Scanning electron microscopy (SEM) analysis showed that P. ramosa seeds have varying shapes and seed coat have fibrillar periclinal cell wall. In addition to all the known host species for P. ramosa till date, we also identified a new host, a wild Brassicaceae weed species; Lepidium didymum in Haryana. The presence of an alternative weed host may help P. ramosa survive even in the absence of major crop host species. Overall, the present study revealed some insights into the P. ramosa-B. juncea host-parasite complex and its effect on B. juncea which could be further investigated in more detail.

Emergence and Potential Spread of Rust Disease on Wisteria floribunda and Corydalis incisa Influenced by Climate Change in Korea

Global climate change influences the emergence, spread, and severity of rust diseases that affect crops and forests. In Korea, the rust diseases that affect Wisteria floribunda and its alternate host Corydalis incisa are rapidly spreading northwards. Through morphological, molecular, phylogenetic, and pathogenicity approaches, Neophysopella kraunhiae was identified as the causal agent, alternating between the two host plants to complete its life cycle. Using the maximum entropy model (Maxent) under shared socioeconomic pathways (SSPs), the results of this study suggest that by the 2050s, C. incisa is likely to extend its range into central Korea owing to climate shifts, whereas the distribution of W. floribunda is expected to remain unchanged nationwide. The generalized additive model revealed a significant positive correlation between the presence of C. incisa and the incidence of rust disease, highlighting the role that climate-driven expansion of this alternate host plays in the spread of N. kraunhiae. These findings highlight the profound influence of climate change on both the distribution of a specific plant and the disease a rust fungus causes, raising concerns about the potential emergence and spread of other rust pathogens with similar host dynamics.

An important consideration when expressing mAbs in Escherichiacoli

Monoclonal antibodies (mAbs) are a driving force in the biopharmaceutical industry. Therapeutic mAbs are usually produced in mammalian cells, but there has been a push towards the use of alternative production hosts, such as Escherichia coli. When the genes encoding for a mAb heavy and light chains are codon-optimized for E. coli expression, a truncated form of the heavy chain can form along with the full-length product. In this work, the role of codon optimization in the formation of a truncated product was investigated. This study used the amino acid sequences of several therapeutic mAbs and multiple optimization algorithms. It was found that several algorithms incorporate sequences that lead to a truncated product. Approaches to avoid this truncated form are discussed.

Three Decades of Rust Surveys in the United States Reveal Drastic Virulence Changes in Oat Crown Rust.

To better understand how the pathogenicity of the oat crown rust pathogen Puccinia coronata f. sp. avenae (Pca) has changed in the United States, 30 years of United States Department of Agriculture (USDA) survey isolates (n = 5,456) tested on 30 to 40 differential lines were analyzed for overall and Pc-resistance-gene-specific virulence trends and correlations. Pca is incredibly pathologically diverse, with 88% of races represented by a single isolate. There are a slightly higher proportion of unique races from the Northern region of the United States, and for one fourth of the years, Northern region isolates were significantly more virulent than Southern isolates, which supports the idea that sexual recombination in this region is mediated by the alternate host as a major factor in creating new races. However, there is also support for regular isolate movement between North and South regions as isolates in the United States are steadily accumulating virulences at a rate of 0.35 virulences per year. Virulence significantly increased for 23 and decreased for four of the 40 differential lines. In the past few years, virulence has reached 90% or greater for 16 differential lines. There were also strong correlations in virulence for certain Pc genes that are likely identical, allelic, or target the same or closely linked pathogen effectors (e.g., Pc39, Pc55, and Pc71), and the results were largely in concordance with recent genome-wide association study (GWAS) effector studies using USDA isolate subsets. Understanding changes in Pca pathogenicity is essential for the responsible deployment and management of Pc resistance genes for sustainable and profitable oat production.

The capacity of Trichogramma chilotraeae (Hymenoptera: Trichogrammatidae) to parasitize Spodoptera frugiperda reared with natural diet vs artificial diet vs alternate host

Parasitoids can be mass-produced easily using artificial diets or an alternate host. This research examined Trichogramma chilotreae’s ability to parasitize S. frugiperda (reared on different diets) and Corcyra cephalonica eggs (alternate host). The research was conducted using a completely randomized design. The treatment used is the type of egg (50 eggs of S. frugiperda fed on a natural and artificial diet during the larval stage and 50 eggs of C. cephalonica). These eggs were exposed for 24 hours to one mated female of T. chilotraeae and then reared until the emergence of adult parasitoids. Results show that T. chilotraeae parasitized more S. frugiperda eggs fed on a natural or artificial diet than C. cephalonica eggs. However, the parasitization rate was the same between the three. Similar to the sex ratio of the resulting T. chilotraeae offspring, S. frugiperda eggs fed on a natural diet produced more female offspring than S. frugiperda eggs fed on an artificial diet or on C. cephalonica eggs, indicating that mass rearing of T. chilotraeae can be carried out using a host in the form of S. frugiperda eggs from adult fed on artificial diet during a larval stage or by using C. cephalonica eggs.

Seasonal fluctuation and alternative host plants of vegetable crop-infesting tephritids in non-vegetable growing areas in South Sudanese zone of Burkina Faso.

This study was carried out in 3 types of biotopes where vegetable crops are not grown to highlight their contribution to the dynamics of vegetable-infesting flies. To this end, a trapping system based on a sexual attractant, the Cuelure associated with an insecticide was set up in 18 biotopes (6 natural areas, 6 mango orchards, and 6 agroforestry parks) in the regions of Hauts Bassins and Cascades in the South-West of Burkina Faso. During the trapping monitoring, which was done every 2wk to collect insects captured, fruits present in 3 types of biotopes were sampled and incubated for insect emergence. Ten Dacus (Fabricius) [Diptera: Tephritidae]species and Zeugodacus cucurbitae (Coquillett) [Diptera: Tephritidae] were trapped in the study area. The predominant species captured was Z. cucurbitae (52.93%) followed by Dacus punctatifrons (Karsch) [Diptera: Tephritidae] (29.89%) and Dacus humeralis (Bezzi) (12.71%). Six tephritid species were emerged from 6 wild fruit species belonging to Cucurbitaceae, Apocynaceae, and Passifloraceae families. Fruit flies were more abundant from Jul to Nov with peaks observed in Aug or Oct depending on the species. Citrullus colocynthis L. (Cucurbitaceae), Lagenaria sp. (Cucurbitaceae), Passiflora foetida L. (Passifloraceae), and Passiflora sp. acted as reservoir host plants of Dacus ciliatus (Loew), Dacus bivittatus (Bigot), Dacus vertebratus (Bezzi) [Diptera: Tephritidae], D. punctatifrons, and Z. cucurbitae, the major vegetable insect pests in West Africa. The 3 types of biotopes acted as suitable refuge areas of vegetable crop-infesting fruit flies either for the favorable microclimate or for the alternative host plants.

Conservation of natural enemies of Diaphorina citri and their impact on Huanglongbing: Analysis and perspectives

Diaphorina citri is the main vector of Candidatus Liberibacter asiaticus (CLas), the causative agent of HLB, the most devastating citrus disease. Although the importance of biological control is recognized, insecticides are the main control tool used. Its use in citrus should be cautious, as it could interfere with the biocontrol of exotic pests already present. Diaphorina citri has a wide range of natural enemies; however, only the parasitoid Tamarixia radiata and some species of entomopathogenic fungi are used inundatively. Although the main predators of the vector occur naturally, few studies address their conservation in situ. This review supports the idea that the conservation of natural enemies should be the basis of the integrated management of D. citri and CLas. The conservation of alternate hosts, the inclusion of nectar plants, in situ conservation of parasitoids, and the autodissemination of entomopathogenic fungi are proposed. Studies carried out on conservation of natural enemies of D. citri and related pests, their probable impact on the disease, and prospects for implementation in Mexico are analyzed and discussed. The proposed strategies could enhance not only the biological control of D. citri-CLas, but also the autoregulation of citrus pests in general.

Life history and overwintering in multi‐ and univoltine species of family Tephritidae in a subtropical region of northwestern Argentina

AbstractAmong phytophagous insects, life history often evolves as a strategy to cope with seasonality in host plant availability. Whereas specialization often leads to dormancy, aestivation, or longevity, polyphagous species bridge between periods of host availability by exploiting alternative host plants. The aim of the present work was to characterize the life histories of four species of specialist and generalist uni‐ and multivoltine frugivorous fruit flies – Ceratitis capitata Wiedemann, Anastrepha fraterculus Wiedemann, Rhagoletis blanchardi Aczel, and Rhagoletotrypeta pastranai Aczel (all Diptera: Tephritidae) – inhabiting in sympatry in Las Yungas phytogeographical province in Tucumán (northwestern Argentina). For this purpose, infested host plant fruits were sequentially collected during two consecutive years, and flies recovered from these fruits were subjected to demographic experiments to establish longevity and overwintering mechanisms. The results indicated that life cycles were tightly related to host fruit availability, where multivoltine species sequentially exploit different host plants over the year, whereas univoltine species must undergo pupal dormancy to reach the next host fructification period and may extend the duration of dormancy when climatic conditions are acyclic and unpredictable. The present study may broaden knowledge about diapausing Tephritidae in subtropical regions and may contribute to an increased conceptual basis for the improvement of pest control strategies, such as the sterile insect technique (SIT).

Long-term suitability of an alternative host for rearing the sugarcane stalk borer parasitoid Tetrastichus howardi.

The continuous utilisation of an alternative host may influence parasitoid performance across successive generations due to conditioning in natal hosts. Tetrastichus howardi (Olliff) has successfully been reared using Tenebrio molitor L. pupae as a feasible alternative host. However, the extended rearing of T. howardi on this alternative host may impact the biological features of the parasitoids. Parasitoids were reared using T. molitor pupae for 30 consecutive generations. Quality criteria were assessed during the generations F5, F15, and F30, offering pupae of the target pest, Diatraea saccharalis (Fabr.), and compared with the F0 generation (parasitoids reared in D. saccharalis pupae). Criteria included assessments of parasitism performance, host selection, and wing form variation in the parasitoid wasps. Additionally, we examined the fecundity of T. howardi females that emerged from both hosts, considering their age, egg loading before and after one oviposition, as well as parasitism of sugarcane stalk borer pupae. Rearing T. howardi using pupae of T. molitor did not affect its biological traits or preference for the target pest for 30 generations. After parasitism, the parasitoid left the host pupa inside the stalk, and one oviposition was enough to kill D. saccharalis pupae and obtain viable parasitoid progeny. Female sexual maturation and egg loading occurred 72 and 96 h after parasitoid emergence. Egg-loading recovery after parasitism did not happen within 24 h. T. howardi can be reared for up to 30 generations using alternative hosts without compromising its parasitism performance or egg loading.

Host tree-based scenario modelling for predicting a key edible insect, mopane worm Gonimbrasia belina (Westwood, 1894) distribution in Southern Africa

Abstract Gonimbrasia belina, known as the mopane worm, is a large edible caterpillar in tropical and subtropical regions. However, little is known about the bioecology of this species as influenced by its host trees. This study evaluated the importance of different potential host trees in understanding mopane worms’ behaviour and spatial distribution. To assess their relative importance, the study compared models incorporating various mopane worm host trees and predictor variables. Using the species distribution modelling (SDM) package in R, an ensemble of random forest (RF), support vector machine (SVM), and boosted regression tree (BRT) algorithms were used to assess the spatial extent of mopane worm distribution in Southern Africa. Four host tree-based scenarios were developed to assess their contribution to the relative distribution of the mopane worm i.e. (1) by excluding all the potential host trees as explanatory variables and considering only the environmental variables, (2) focusing on the primary host tree, Colophospermum mopane as an explanatory variable together with the other environmental variables, (3) incorporating all the host trees, including C. mopane and (4) examining all other host trees excluding C. mopane. Results demonstrated that incorporating all host trees enhanced the models’ predictive abilities (mean AUC = 0.87) underscoring the significant impact of the alternative host trees on the mopane worm distribution patterns beyond just the C. mopane. This study highlights the significance of host trees in predicting the behaviour and distribution of mopane worm populations, providing valuable insights and decision-making for mopane worm use as an alternative protein source, conservation efforts, and land management practices.

Halophytic Bacterial Endophyte Microbiome from Coastal Desert-Adapted Wild Poaceae Alleviates Salinity Stress in the Common Wheat Triticum aestivum L.

Abiotic stresses threaten the strategic crops of Poaceae (Gramineae) worldwide. Habitat-adapted microbiome of wild plants has the potential to alleviate abiotic stresses in alternate hosts. Persian Gulf's coastal deserts are colonized by halophyte plants hosting habitat-adapted halophytic microbiota. Here, endophytic bacteria from wild Poaceae in coastal deserts of the north Persian Gulf at Hormozgan province, Iran, were isolated and screened for mitigating salinity stress in wheat. Accordingly, seven dominant species of wild Poaceae in the region, i.e., Aeloropus lagopoides, Aeloropus litiralis, Chrysopogon aucheri, Cymbopogon olivieri, Desmostachya sp., Halopayrum mucronatum, and Sporbuls arabicus, were explored. In total, 367 endophytic bacteria were isolated, 90 of which tolerated 2.5-M NaCl. Of these, 38 strains were selected based on their bioactivity and applied for in vitro wheat-interaction assays under 250-mM NaCl stress. Five superior strains promoted seed germination and growth indices in rain-fed winter wheat cv. Sardari, i.e., Bacillus subtilis B14, B19, & B27, Bacillus sp. B21, and Bacillus licheniformis Ba38. In planta assays in saline soil (2.7 dS m-1) using the superior strains indicated that Bacillus sp. B21 and Bacillus licheniformis Ba38 increased germination and root and shoot lengths and their dry and fresh weights in wheat seedlings. Moreover, phenolics and flavonoids contents of wheat seedlingswere influenced by endophyte application. Thus, the coastal desert-adapted microbiome of wild Poaceae could alleviate abiotic stress and promote growth in cultivated species of Poaceae, such as wheat.

Hordatines, dimerised hydroxycinnamoylagmatine conjugates of barley (Hordeum vulgare L.): an appraisal of the biosynthesis, chemistry, identification and bioactivities

AbstractHydroxycinnamoylamides are specialised metabolites widely distributed in the plant kingdom. These are phenolic moieties covalently linked to mono- or polyamines through amide bonds. Their oxidative coupling (dimerisation) leads to neolignanamides, a group of compounds showing high chemical, structural and functional diversity. Typical to barley, dehydro dimers of hydroxycinnamoylagmatines, hordatines are primarily found in germinated seeds and at the seedling stage. The first step in the biosynthesis of hordatines is catalysed by acyl-coenzyme A-dependent N-hydroxycinnamoyltransferases, and lead to the formation of hydroxycinnamoylagmatines (HCAgms). The oxidative homo- or hetero-dimerisation of the latter results in different hordatines (A, B, C or D). Hordatines can also undergo various types of conjugation and form hydroxylated, methylated or glycosylated derivatives. Although the research on the bioactivities of the hordatines is still nascent, the in planta antifungal properties have long been recognised. While hordatines are naturally and uniquely synthesised in barley plants, these molecules or lead compounds derived therefrom, also exhibit medicinal and pharmaceutical uses important for human health, stimulating research into the utilisation of biotechnology in alternative production hosts and to enhance agricultural yields and value-added production. This review summarises the older and recent knowledge about hordatines and derivatives and may serve as a springboard for future research on this intriguing class of secondary plant metabolites.

Why moving there? Spanish SIEs: factors and motivations involved in the choice of the host destination

PurposeThis paper aims to explore the Spanish Self-Initiated Expats’ (SIEs) motivations and factors involved in the choice of the host destination.Design/methodology/approachThrough an exploratory and qualitative study, drawing upon SIE literature on motivations and careers, 22 Spanish SIEs were interviewed in a semi-structured way.FindingsMost SIEs clearly detailed the line of reasoning behind the host destination choice (specific destination); a second group considered a limited number of potential countries to relocate to (alternative destinations), and the smallest one did not choose a specific location. Career motivations were the most mentioned ones and different degrees of career planning were found: those with a very defined career planning process relied upon one potential destination, while those with a less defined one considered several alternative host destinations. The European Region Action Scheme for the Mobility of University Students experience was one of the most mentioned factors influencing the choice of the host destination, which may be common to other European Union (EU) nationals. As to the limiting ones, the visa requirements outside the EU were identified. Other factors were particular to Spain, such as the perceived need for English proficiency for a successful global career and the degrees of career planning.Practical implicationsThese findings may assist Talent Management Managers to align organizational strategies with SIEs motivations. They may also help future Spanish and European SIEs in their individual career management process.Originality/valueThis study contributes to a better understanding of the expatriation motivations and factors influencing the destination location of Spanish SIEs, adding to the SIE and global career literature.