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Copyright of Biotechnologie, Agronomie, Societe et Environnement is the property of Les Presses Agronomiques de Gembloux and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Stromatinia cepivora, the causal agent of white rot, is responsible for 60–80% of economic losses in onion and garlic crops. This work aimed to select biological control agents (BCAs) to control white rot. Ten microorganisms were tested for hyperparasitic activity on S. cepivora sclerotia in garlic (Allium sativum). Bioassays consisted of pots filled with sterile soil and 50 sclerotia in a plastic tulle bag. Four microorganisms were selected to compare their capability for degrade sclerotia on garlic. Our results showed that increasing degradation happened when Th034, Th035, Th003, and Bs006 were added to the pots containing garlic. Subsequently, three application techniques (seeds, seedlings at transplant, and seeds and transplant) were evaluated. Seven BCAs applied singly and in mixtures were evaluated in semi-field experiments for their ability to reduce white rot symptoms in onion plants in soil inoculated with 300 sclerotia per kilogram. The results indicated that efficacy was dependent on microrganism, mixture, and technique of application. The synergy factor showed that only two treatments have synergistic effects. In both cases, the mixture consisted of a strain of Bacillus and two species of Trichoderma (T. koningiopsis, T. atroviride) applied twice. In most cases, antagonistic interactions among BCAs were observed. [ABSTRACT FROM AUTHOR]

Crown gall is a globally recognized bacterial disease caused by Agrobacterium tumefaciens. This bacterium is characterized by its potential to infect a wide range of plants, specifically fruit trees. In Morocco, almond trees (Prunus amygdalus) are among the most heavily affected species by this disease. In our study, all tested bacteria were isolated in the laboratory from infected almond samples exhibiting tumors at the crown and root of the sampled trees collected from northwestern of Morocco. Biochemical, pathogenicity and molecular identification were performed to identify the causal agent of almond crown gall. Molecular identification was done using a duplex PCR (A/C9 and A/E9) targeting virD2gene located in the pTi plasmid, which is the oncogenic element of the bacterium. The results showed that 12 from 20 isolates were identified as tumorigenic A. tumefaciens with the presence of pTi. Moreover, these isolates were found to exhibit tumorigenic properties both in vitro and in vivo when tested on indicator plants, specifically tomato and carrot discs. The efficacy of agrocin synthesized by Agrobacterium radiobacter strain K1026, a biopesticide known as NoGall, was tested in vitro and in planta against tumorigenic strains of A. tumefaciens. Our results revealed a significant inhibitory effect in vitro, with inhibition percentages ranging from 29.5% to 38.9%. Additionally, we observed a complete reduction in tumor growth at the inoculation sites on indicator plants, with a 100% reduction percentage.

This study aimed to investigate the efficacy of Ascophyllum nodosum extract, in combination or not with biocontrol agents, in the management of Meloidogyne javanica in soybean, assess treatment effects on soil biological activity, and determine the total phenolic content of the extract. The experiment was conducted according to a 5 × 2 factorial design, with three biocontrol agents (Bacillus methylotrophicus, Pochonia chlamydosporia, and Trichoderma harzianum), a chemical nematicide (abamectin, positive control), and an untreated (negative) control, each in the presence and absence of A. nodosum extract. Treatments included six replications. Nematode inoculation (2000 eggs + juveniles of M. javanica per plant) was performed at the time of sowing. Sixty days later, plants were evaluated for height, shoot weights, numbers of M. javanica eggs and J2 extracted from roots, and soil biological activity. Biological and chemical nematicide treatments were effective in reducing M. javanica multiplication. There was a synergic effect of A. nodosum extract on M. javanica multiplication for the treatments with A. nodosum + T. harzianum, A. nodosum + abamectin (Trial 1) and A. nodosum + P. chlamydosporia (Trial 2). B. methylotrophicus and T. harzianum treatments enhanced plant development and soil microbial biomass carbon. Higher values of soil basal respiration and metabolic quotient (qCO2) were observed in the A. nodosum + abamectin treatment. A. nodosum extracts at 75 g L−1 had a total phenolic content of 13 255 and 11 608 mg GAE 100−1 g in Trials 1 and 2, respectively. [ABSTRACT FROM AUTHOR]

Bracon hebetor Say, a versatile parasitic wasp known for its adaptability and gregarious behavior, plays a crucial role in controlling lepidopteran pests in various environments. This study aimed to investigate the reproductive success of a wild population of Bracon hebetor within a storage facility in Ouargla, Algeria. The study focused on two date varieties, Itim and Ghars, which were stored in crates and cloth bags, respectively. The parameters assessed included the infestation rate by date moth larvae, parasitism rate, and life cycle stages of Bracon hebetor in the dates. The results revealed a higher infestation rate of Itim dates by Ectomyelois ceratoniae compared to Ghars dates. Furthermore, 39% of infested Itim dates and 23% of infested Ghars dates contained Bracon hebetor individuals. The reproductive success of Bracon hebetor was relatively low, as indicated by the presence of a higher number of dead pupae in both date varieties. These findings contribute to the understanding of dynamics of the Bracon hebetor and its effectiveness in controlling date moth populations. Itim dates are more susceptible to infestation, emphasizing the need for targeted pest management strategies. This research provides valuable insights for the development of effective date moth control measures in date production systems. Further research is warranted to explore these factors. [ABSTRACT FROM AUTHOR]

Avian species were historically thought to have a very limited sense of smell. However, recent studies suggest that odor plays an important role in many areas of avian life, including foraging and navigation. It has been shown that insectivorous birds can interact in a tritrophic fashion with plants and their herbivores by cuing in on herbivore-induced plant volatiles (HIPVs), important signaling compounds released by plants in response to herbivorous damage. This phenomenon has been observed in a number of plant species, including complex HIPV blends in corn (Zea mays). However, in other species, simpler single-compound HIPVs can act as phytohormones, causing the release of additional HIPVs, and have also been shown to be attractive to birds. Here we test if 2 single-compound general HIPVs, methyl jasmonate and methyl salicylate, attract avian predators to insect prey on corn plants using clay caterpillar models. We observed appreciable levels of bird attacks on our models across 10 experimental sites. However, we did not observe any difference between HIPV and control treatments. Interestingly, we did find that several weather variables, including wind speed and temperature, were significant or near significant predictors of avian predation activity, respectively. Together with previous studies, our results add to a nuanced picture of how birds may be using HIPVs to locate insect prey. Additionally, the potential for birds to act as a natural form of biocontrol in agricultural settings may be affected by physical location and local climate. On pensait historiquement que les espèces aviaires avaient une olfaction très limitée. Cependant, des études récentes suggèrent que l'odeur joue un rôle important dans de nombreux domaines de la vie aviaire, y compris la recherche de nourriture et la navigation. Les oiseaux insectivores peuvent interagir à travers trois niveaux trophiques avec les plantes et leurs herbivores par les signaux des substances volatiles végétales induites par les herbivores (HIPV), les composés de signalisation importants libérés par les plantes en réponse aux dommages causés par les herbivores. Ce phénomène a été observé chez plusieurs espèces végétales, comme le maïs (Zea mays) et ses mélanges complexes d'HIPV. Chez d'autres espèces, les HIPV plus simples et mono-composés peuvent agir comme des phytohormones, provoquant l'émission d'autres HIPV, qui se sont également avérés attrayants pour les oiseaux. Ici, nous testons si deux HIPV à un seul composé, le jasmonate de méthyle et le salicylate de méthyle, attirent les prédateurs aviaires vers les insectes proies sur les plants de maïs en utilisant des modèles de chenilles en argile. Nous observâmes des niveaux appréciables d'attaques d'oiseaux sur nos modèles dans dix sites expérimentaux. Cependant, nous ne trouvâmes aucune différence entre les traitements d'HIPV et les témoins. Il est intéressant de noter que nous constatâmes que plusieurs variables météorologiques, notamment la vitesse du vent et la température, étaient des prédicteurs significatifs ou presque significatifs de l'activité de prédation aviaire, respectivement. Nos résultats, combinés à des études précédentes, décrivent comment les oiseaux peuvent utiliser les HIPV pour localiser les proies d'insectes. De plus, le potentiel des oiseaux à agir comme une forme naturelle de lutte biologique dans les milieux agricoles peut être affecté par l'environnement physique et le climat local. [ABSTRACT FROM AUTHOR]

The citrus leaf miner, Phyllocnistis citrella, is considered a serious pest of nurseries and young citrus plantations, not only in Morocco, but all over the world. According to the literature, different management and control methods; including chemical and biological; control this insect. Chemical control has shown its effectiveness through various active ingredients, such as Imidacloprid and Thiamethoxam (from the Neonicotinoid family), Abamectin (Avermectins) and Fenvalerate (Pyrethrinoids), but it is not sustainable. Biological control in turn knows the use of natural enemies, namely predators and parasitoids as well as other biological control techniques. In this context, ants, lacewings, ladybugs, spiders and bedbugs have been identified as effective predators of the leafminer. Parasitoids also contribute to the control of this pest, and most of them belong to the Eulophidae family. Numerous studies have reported that the species: Ageniaspis citricola, Citrostichus phyllocnistoides, Semiolacher petiolatus, Cirrospilus sp, Chrysocharis sp. and Pnigalio sp are the most effective wasps against the citrus leafminer. Mating disruption has been shown to be effective in reducing leafminer populations. This technique with its various pheromone components has been reviewed in this article. Research is underway to find other tools of control and above all to avoid possible resistance of the insect to commonly used insecticides.

Biocontrol (biological control) and "biocontrôle" (which can be translated into English as "Bioprotection") are concepts of crop protection that have common points but also have their specificities. The former has been known since the 1880s, while the latter appeared in the French landscape in the 2010s. In recent years, there has been regular confusion in the terms and interpretations of these concepts, which are not of the same nature: biocontrol is defined by strategies and "biocontrôle" by products. This paper therefore aims to respond to a need for clarification: it contributes to distinguishing the perimeters and contents of these concepts, to pointing out certain abusive comparisons and to proposing semantic clarifications. It reviews the English and French terms related to biocontrol and "biocontrôle" (Bioprotection) at the European level. Finally, the paper discusses the role and relevance of the two concepts in agroecological crop protection (ACP). Conservation biocontrol has a central place in ACP, as it is based on a systemic and preventive approach to crop pest risks. While some bioproducts are promising for the prevention of pest risks, many of them are part of a curative approach, similar to the use of synthetic chemical pesticides, with the same types of commercial spin-offs for the agro-industry. [ABSTRACT FROM AUTHOR]

Biocontrol, an alternative to chemical control against plant pathogens, may also improve plant health and enhance fruit yield. Tomato production in open fields or greenhouses is constrained by the pathogens Fusarium oxysporum f. sp. lycopersici race 3 (Fol R3) and F. oxysporum f. sp. radicis-lycopersici (Forl). In this work, we studied the biocontrol effect of the antagonistic bacteria Acinetobacter calcoaceticus AcDB3, Bacillus thuringiensis BtMB9, B. subtilis BsTA16, and B. amyloliquefaciens BaMA26 in field trials with four tomato hybrids over two consecutive growing seasons (2019–2020 and 2020–2021). The effect of these bacteria on plant growth was also evaluated. The presence of F. oxysporum in field soil and/or infected plants was confirmed microbiologically. All four bacterial strains significantly suppressed the severity of Fusarium crown and root rot of tomato (FCRRT) and Fusarium wilt symptoms, as well as increased tomato yield under field conditions. Among the four strains, B. subtilis BsTA16 showed the highest reduction in symptoms of Fusarium wilt (68%) and FCRRT (74%). To the best of our knowledge, this is the first report of biological control agents (BCAs) exerting antagonistic activity against both FCRRT caused by Forl and Fusarium wilt caused by Fol in tomato under field conditions. [ABSTRACT FROM AUTHOR]

The purpose of this study was to study the effect of the leaves of Rosmarinus officinalis L. (Lamiaceae), Lonicera japonica L. (Caprifoliaceae) and Nerium oleander L. (Apocynaceae) on some biological parameters of the L5 larvae of the plant. Desert Locust Schistocerca gregaria, by direct feeding and by injection (leaf extracts) under laboratory conditions. The fresh leaves of L. japonica were well appreciated by the S. gregaria L5 larvae and showed no adverse effect on the different parameters studied. On the other hand, leaves and extracts of N. oleander and R. officinalis caused disturbances in the various biological parameters studied, including low weight gains, high mortality rates, and inhibition of fledging. In view of the results obtained, the plants of R. officinalis and N. oleander offer a promising alternative to the use of synthetic pesticides in Desert Locust control. [ABSTRACT FROM AUTHOR]

Copyright of Silva Lusitana is the property of Unidade de Investigacao de Silvicultura e Productos Florestais and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bud rot pathogens cause diseases on Cannabis sativa L. (cannabis, hemp) worldwide through pre- and post-harvest infections of the inflorescence. Seven indoor or outdoor cannabis production sites and three hemp fields were sampled for bud rot and stem canker presence during 2019–2020. Among 178 isolates recovered from diseased tissues, sequences of the ITS1-5.8S-ITS2 region of rDNA, the glyceraldehyde-3-phosphate dehydrogenase (G3PDH) gene and the heat shock 60 (HSP) gene identified the following: Botrytis cinerea (162 isolates), B. pseudocinerea (2), B. porri (1), Sclerotinia sclerotiorum (5), Diaporthe eres (3) and Fusarium graminearum (5). Pathogenicity studies conducted on fresh detached cannabis buds inoculated with spore suspensions or mycelial plugs showed that B. cinerea, S. sclerotiorum and F. graminearum were the most virulent, while B. pseudocinerea, B. porri and D. eres caused significantly less bud rot. Optimal growth of Botrytis species occurred at 15–25°C. In vitro antagonism tests showed that Bacillus spp., Trichoderma asperellum and Gliocladium catenulatum inhibited B. cinerea and S. sclerotiorum colony growth. When applied as a spray 48 h prior to B. cinerea inoculation, all biocontrol agents significantly (P < 0.01) reduced disease development on detached inflorescences. Prolific growth and sporulation of T. asperellum and G. catenulatum were observed on bud tissues. The pathogens B. porri, S. sclerotiorum, D. eres and F. graminearum are described for the first time as cannabis bud rot pathogens. Inoculum from neighbouring fields of diseased garlic, cabbage, blueberry and hay pasture, respectively, likely initiated infection of inflorescences. Several biological control agents show potential for disease reduction through competitive exclusion. [ABSTRACT FROM AUTHOR]

The inventory of the arthropodological fauna in the two agro-systems studied, i.e. the palm grove and the greenhouse, allowed us to note that the family Coccinellidae occupies the first place among the order Coleoptera with an AR% = 35,62% in the month of April in the palm grove and 40.76% in the greenhouse. The palm grove is the richest in ladybird species with 07 species reported (248 individuals) with a predominance of Pharoscymnus ovoideus (13,63%) and Pharoscymnus numidicus (13,46%). At the level of the Greenhouse, only 04 species (325 individuals) are recorded, namely Coccinella algerica (36,30%), Coccinella novomnotata (42,15%), Hippodamiatredecim punctata (15,38%) and Coccinella undecimpunctata (6,15%). The study of the predatory capacity of the ladybirds inventoried showed that Pharoscymnus ovoideus is more voracious (19,33 individuals of white cochineal/24h) compared to Pharoscymnusnumidicus. The aphidiphagous ladybirds also show different predatory abilities. Coccinellanovemnotata is the most voracious with an average of 61,67 individuals/24h. The species Coccinella algerica devours the least amount of aphids with an average of 49,67 individuals/24h. [ABSTRACT FROM AUTHOR]

The fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae) is a voracious pest that preferentially feeds on cereals and other crops of economic importance. Native to America, it has recently invaded sub-Saharan African countries where it is currently threatening food security. There is limited knowledge of the natural enemies of the fall armyworm in Africa. In this study, we aimed to identify arthropods, fungi and entomopathogenic nematodes that naturally control this pest in Burkina Faso. Insect samplings, including larvae and egg masses, were conducted in 47 maize farms from October 2019 to November 2020. About 20 species of parasitoids, predators and entomopathogenic fungus associated with the fall armyworm were identified. The overall parasitism rate was 10.5%. Nematodes (Mermithidae) were the most frequent parasites (73.2% of the parasitized larvae). Identified parasitoids included Hymenopterans [Coccygidium luteum (Brullé), Chelonus bifoveolatus (Szépligeti)] and Dipterans (Drino sp.). Predators included Areneae and insects belonging to the following families: Carabidae (Calleida sp.), Coccinellidae [Cheilomenes sulphurea (Olivier)], Forficulidae [Diaperasticus erythrocephalus (Olivier), Forficula senegalensis (Serville)], Formicidae [Pheidole megacephala (Fabricius) and others], Mantidae, Pentatomidae and Reduviidae (Rhynocoris sp.). The most abundant predators were members of the Forficulidae (51%), Formicidae (15%) and Coccinellidae (13%). We advocate for the development of conservation biological control since this approach can be simple and cost-effective to control this pest. [ABSTRACT FROM AUTHOR]

Copyright of Biotechnologie, Agronomie, Societe et Environnement is the property of Les Presses Agronomiques de Gembloux and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Powdery mildew, caused by Podosphaera xanthii (U. Braun & Shishkoff), is a widespread disease on greenhouse cucumber in many countries, including Canada. The efficacy of seven biological or chemical products to manage powdery mildew was evaluated. These included Rhapsody® (Bacillus subtilis Ehrenberg strain QST 713), Microflora PROTM (B. subtilis, Bacillus amyloliquefaciens Priest et al., Bacillus pumilus Meyer & Gottheil), Prestop® (Gliocladium catenulatum J.C. Gilman & E.V. Abbott strain J1446), Double Nickel LC (B. amyloliquefaciens strain D747), Active Flower™ (fertilizer containing N:P:K of 8:4:12 plus 3% boron), Luna® (fluopyram and pyrimethanil) and Pristine® (pyraclostrobin and boscalid). Products were applied as preventative or eradicative treatments at weekly intervals to the moderately susceptible cucumber cultivars 'Picowell RZ' or 'Tasty Green'. Disease severity was rated after 3–4 applications as the number of colonies that developed on leaves, or as a percentage of leaf area infected calculated using image analysis. Rhapsody at a rate of 1.5% provided the most significant disease reduction compared with the other three biological products, although rates of 2% and 4% also resulted in high disease suppression in a second experiment. The fungicides Luna (0.5 mL L−1) and Pristine (0.66 g L−1) provided a level of control comparable to Rhapsody. Application of ActiveFlower at 0.5 and 0.3 mL 100 mL−1 significantly reduced powdery mildew after three applications, but some phytotoxicity was observed at the higher rate. The products tested in this study can be part of an integrated powdery mildew management programme for greenhouse cucumber. [ABSTRACT FROM AUTHOR]

The use of chemicals against crop pests is more popular, in the world, than organic alternatives. These pesticides have shown harmful effects on humans and their environment. The present study aims to contribute in the creation of a biological control method against the cereal aphid Rhopalosiphum maidis by the application of extracted essential oils from rosemary (Rosmarinus officinalis) collected from three regions in Algeria (Tebessa, Constantine and El Wadi). In order to test the insecticidal potential of this plant against the adults of this pest, three concentrations (50ųl, 100ųl and 200ųl) were tested. The results reveal that R. officinalis has a very important effect on the individuals of R. maidis because the mortality, which increases with time and concentration, reached 100% with the 3rd dose after only five days. Besides, the samples from Tebessa seem more efficient than those from other localities because this rate was recorded after only three days. [ABSTRACT FROM AUTHOR]

Thirty-three species of aphids are now established in New Caledonia. All species appear to have been introduced accidentally by human activity in the last century. Here, 17 aphid species are recorded for the first time: Aphis eugeniae, Aphis glycines, Aphis odinae, Aulacorthum solani, Brachycaudus helichrysi, Cerataphis orchidearum, Greenidea psidii, Hyperomyzus carduellinus, Hysteroneura setariae, Lipaphis pseudobrassicae, Micromyzus katoi, Myzus ornatus, Pentalonia caladii, Rhopalosiphum nymphaeae, Rhopalosiphum rufiabdominale, Schizaphis rotundiventris, and Tetraneura fusiformis. Thirteen more species are also more or less regularly intercepted at the borders through biosecurity surveys, without further establishment. This demonstrates that aphids represent a major biosecurity threat, including a threat as potential plant virus vectors. The reinforcement of biosecurity is a priority for such biodiversity hotspots, from the perspectives of both agriculture and the native environment. Prioritisation and promotion of local development of vegetable and fruit production, rather than their risky importation from abroad, is desirable. Such an approach also should be promoted and extended to other Pacific islands, which all share the lack of native aphid fauna and their associated plant disease vector risks. [ABSTRACT FROM AUTHOR]

Copyright of Biotechnologie, Agronomie, Societe et Environnement is the property of Les Presses Agronomiques de Gembloux and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A shift to larger farms, bigger equipment and reduced crop diversity has been occurring in North American agriculture for many years. This has resulted in an increased reliance on genetic resistance and pesticides because much of the pest reduction from natural biological control (ecosystem services) associated with crop rotation and biological diversity has been lost. This shift has contributed to erosion of cultivar resistance and loss of sensitivity to pesticides. However, the impending change to autonomous field equipment represents an opportunity to reverse the trend towards ever-larger farm equipment. Small autonomous units have the potential to make intercropping, deployment of multi-lines, precision agriculture and even crop rotation, easier and more cost-effective. Remote sensing using drones, combined with precision application of pesticides and improved weather forecasts to help select optimum conditions, could improve the efficacy of both biocontrol agents and synthetic pesticides. Similarly, technologies such as marker-assisted selection for complex traits, gene editing to provide novel sources of resistance, and RNAi (gene silencing) to manage target pest populations could reduce reliance on synthetic pesticides. Crop rotation and improved strategies for deploying genetic resistance, combined with smaller fields, improved scouting and optimized pesticide application, could shift the balance back towards biological diversity and natural biological control within fields. Adding improved genetics for resistance to this mix could further reduce the need for large-scale pesticide application, and minimize both the use and impact of synthetic pesticides in agricultural systems. [ABSTRACT FROM AUTHOR]

Copyright of Biotechnologie, Agronomie, Societe et Environnement is the property of Les Presses Agronomiques de Gembloux and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Since years, many plants contain components that have antifungal effect against plant pathogens. As a biological control, several plant extracts, belonging to the family of Amaranthaceae, have been tested against some phytopathogenic fungi from different crops. For this, an antifungal test of an indigenous plant extracts from the south eastern Algeria was evaluated for its inhibitory effect on phytopathogenic fungicausing date palmdiseases, Alternaria sp., Fusarium sp., Phytophthora sp. and Cladosporium sp.The aqueous extract of this plant showed the maximum inhibition with Phytophthora sp.which recorded 90,6 % at 100% and 83,0 % at 50%, followed by Cladosporium sp. (D2: 89,02%; D3: 89,10%; D4: 86,15%). Statistical analysis confirms that all the doses of H. strobilaceum had a significant effect, comparatively with the control, of inhibition against the tested phytopathogenic fungi mentioned before with p < 0,05; p = 0,0087. High inhibition was detected against Phytophthora sp. and Cladosporium sp. with all the doses, unlike, Fusarium sp. was exhibited only in the fourth dose and Alternaria sp. that was revealed a low rate in the fourth dose. These effective plant extracts may contribute to development of potentially effective and environmentally safer alternative fungicide to control date palm diseases caused by these phytopathogenic fungi. [ABSTRACT FROM AUTHOR]

Copyright of Biotechnologie, Agronomie, Societe et Environnement is the property of Les Presses Agronomiques de Gembloux and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Postharvest diseases pose serious threats to the pome fruit industry worldwide. Grey mould, Mucor rot and blue mould decay on apples, caused by Botrytis cinerea, Mucor piriformis and Penicillium expansum, respectively, are the most economically important postharvest fungal pathogens in apple storage in British Columbia, Canada. The biocontrol capability of Pseudomonas fluorescens isolate 4–6 alone, or in combination with calcium chloride (CaCl2), sodium bicarbonate (SBC) or salicylic acid (SA), against B. cinerea, M. piriformis and P. expansum was evaluated in vitro and on 'Ambrosia' apple in commercial cold storage at 1°C. The combination of the antagonist with the chemical additives generally did not enhance the level of control of the pathogens in vitro. The combination of isolate 4–6 with SBC did provide levels of control of B. cinerea, M. piriformis and P. expansum comparable to the commercial fungicide Scholar® on 'Ambrosia' apples after 15 weeks in cold storage. The biocontrol capability of P. fluorescens isolates 1–112, 2–28 and 4–6 to control B. cinerea, M. piriformis and P. expansum was also evaluated on 'Ambrosia' apples in commercial controlled atmosphere (1.5% CO2 + 1.2% O2) storage at 1°C. All three isolates of P. fluorescens significantly (P < 0.05) inhibited the development of grey mould and blue mould on 'Ambrosia' apples after CA storage, and provided levels of control comparable to BioSave® (containing Pseudomonas syringae ESC-10). These results suggest that P. fluorescens has the potential to control common postharvest fungal pathogens during commercial storage, and by combining the antagonist with SBC, decay can be reduced to a commercially acceptable level. [ABSTRACT FROM AUTHOR]

Copyright of Biotechnologie, Agronomie, Societe et Environnement is the property of Les Presses Agronomiques de Gembloux and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Algerian Journal of Environmental Science & Technology is the property of Algerian Journal of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The control of soilborne crop pathogens is conditioned by the limited management options due to difficult access to active infection courts and to restrictions in the use of synthetic pesticides in Europe. For most soilborne sunflower pathogens, an effective management relies on genetic resistance which is, however, hindered by new pathogen populations (new races). Special emphasis is thus put on updated monitoring and characterization of pathogens and on the enlargement of the set of tools for disease management. Concerning characterization, advances on the population structure of Verticillium dahliae affecting sunflower by means of genetic, molecular and pathogenic approaches are presented. Also in relation to increases of sunflower wilt diseases recently observed, the fungus Cadophora malorum has been identified in Russia and reported as a new pathogen of this crop. Third, new races of Plasmopara halstedii (sunflower downy mildew), have been identified in Spain and Portugal. Most of them have a high virulence, since they overcome several genes for resistance. With regard to alternatives for disease control, entomopathogenic fungi (EF) constitute a novel tool. Used for years in Integrated Pest Management strategies due to their efficacy in controlling insect pests affecting crops, new ecological roles of these fungi have recently been reported. The EF species Beauveria bassiana and Metarhizium brunneum have been assessed by their in vitro effect against V. dahliae and C. malorum by our research group. Our results suggest that antibiosis and/or competition for ecological niche are operating in some EF-pathogen interactions. In summary, pathogen characterization is essential for genetic resistance for worldwide environments of sunflower production. Moreover, the security of sunflower yield and profitability is dependent not only on effective genetic resistance, but also on additional new control options that can be included in successful strategies of sunflower disease management. [ABSTRACT FROM AUTHOR]

The biocontrol strain BJ-1 was isolated from a contaminated Magnaporthe oryzae culture plate and identified as Bacillus subtilis based on morphological characteristics, Biolog Microlog identification and 16S rDNA sequence analysis. The dual culture test showed that BJ-1 has a wide antimicrobial spectrum, and is especially potent against M. oryzae. The culture filtrates of BJ-1 significantly inhibited mycelial growth of M. oryzae P131, caused mycelial disintegration and induced swollen germ tubes. RT-PCR revealed the expressions of seven lipopeptide synthesis genes, encoding surfactin (srfAA and SPAB-ERIB), fengycin (fenB and FENCEA), subtilin (spa and spaS) and bacilysin (BACD) in BJ-1. Application of 1 × 108 CFU mL−1 bacterial cells or 5% culture filtrates of BJ-1 completely suppressed rice blast on detached leaves. In pot experiments, both spray and seed treatments using culture broth provided more than 50% disease suppression on rice blast. Interestingly, rice seeds soaked in culture broth of BJ-1 before planting induced host systemic resistance to inhibit rice blast development and promote plant growth, with disease reduction of over 70%, at a similar level as the fungicide tricyclazole. Expressions of two PR genes (OsPR1a and OsPR10) and three genes (OsPAL, OsICS1 and OsAOS2) known to function in salicylate- and jasmonate-dependent defence signalling pathways in rice plants after seed treatment by culture broth of BJ-1 were significantly induced. This is the first description of the use of B. subtilis as a seed treatment for control of rice blast and these results indicate that B. subtilis BJ-1 is a highly promising biocontrol agent for suppression of rice blast disease. [ABSTRACT FROM AUTHOR]

Copyright of Fruits is the property of International Society for Horticultural Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Heterobasidion irregulare(Underw.) Garbel. & Otrosina is an important fungal parasitic basidiomycete of coniferous trees throughout temperate regions of the world. In Canada, the disease was first reported on red pine in Ontario in 1955, then in Quebec in 1989. As infection probability is proportional to the density of its aerial basidiospores infecting freshly cut pine stumps, the purpose of this study was to quantify theH. irregulareaerial basidiospore deposition along a southern Quebec transect. Spore counts from automated rotary arm collectors were determined by using a ribosomal ITS TaqMan real-time PCR detection assay. Total count was performed on rods at each location, with the highest score of 706.3 spores in Harrington, then 459.6 spores in Cowansville, rapidly decreasing to 52.3 spores in Compton and reaching lows in St-Aubert and Rimouski, with an eastward direction on the transect. Clearly, plantations in southwestern Quebec are at a higher risk of infection than anywhere else in the province. With few exceptions, weekly spore depositions at all sites other than Harrington were greatly below 0.2 per m−2 h−1. Despite this very low spore deposition rate observed in one season, the large number of trees thinned annually warrants that stump treatment with Rotstop® C is still the best strategy, especially in valuable plantations, to prevent against infection byHeterobasidion. Heterobasidion irregulare(Underw.) Garbel. & Otrosina est un important basidiomycète parasite des conifères des régions tempérées de la planète. Au Canada, la maladie a été détectée pour la première fois en Ontario, en 1955, sur le pin rouge, puis au Québec en 1989. Étant donné que la probabilité d’infection est proportionnelle à la densité des basidiospores dispersées par voie aérienne infectant les souches des arbres qui viennent d’être coupés, l’objectif de cette étude était de quantifier le dépôt des basidiospores deH. irregularedispersées par voie aérienne le long d’un transect traversant le sud du Québec. Les d&#xe9.comptes de spores résultant des collecteurs automatiques à bras rotatifs ont été déterminés par analyse de détection basée sur une PCR en temps réel de type TaqMan de l’ITS ribosomique. Le d&#xe9.compte total a été effectué sur des tiges à chaque location, le plus haut compte étant de 706.3 spores, provenant de Harrington, puis de 459.6 spores, de Cowansville, décroissant rapidement à 52.3 spores à Compton pour atteindre les plus bas comptes à Saint-Aubert et à Rimouski, en direction est en suivant le transect. De toute évidence, les plantations du Sud-Ouest québécois sont plus susceptibles d’être infectées que celles des autres régions de la province. À quelques exceptions près, les dépôts hebdomadaires de spores à tous les sites, sauf à Harrington, étaient bien sous les 0.2/m−2h−1. Malgré ce très faible taux de dépôt de spores observé en une saison, le grand nombre d’arbres prélevés chaque année garantit que le traitement des souches avec Rotstop C est encore la meilleure stratégie, spécialement dans les plantations de grande valeur, pour prévenir l’infection causée parHeterobasidion. [ABSTRACT FROM AUTHOR]

Copyright of Fruits is the property of International Society for Horticultural Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)