Exogenous Cytokinin Induces Callus and Protocorm-Like-Bodies Formation in Root Tips of Andrews.

Vanilla is a popular flavouring essence derived from the pods of vanilla orchid plants. Due to the high demand for vanilla flavour, high yielding vanilla plantlets are necessary for establishing vanilla plantations. Clonal micropropagation is a viable technique for the mass production of high yielding vanilla plantlets.

Chitosan controls postharvest anthracnose in bell pepper by activating defense-related enzymes.

Anthracnose, a postharvest disease caused by the fungus Colletotrichum capsici is the most devastating disease of bell pepper that causes great economic losses especially in tropical climates. Therefore, the objective of this study was to evaluate the antifungal properties of chitosan (low molecular weight from crab shell, Mw: 50 kDa and 75-85 % deacetylated) against anthracnose by inducing defense-related enzymes. The concentrations of 0, 0.

The potential for underutilized crops to improve security of food production.

Staple crops face major challenges in the near future and a diversification away from over-reliance on staples will be important as part of the progress towards the goal of achieving security of food production. Underutilized or neglected crops species are often indigenous ancient crop species which are still used at some level within the local, national or even international communities, but have the potential to contribute further to the mix of food sources than they currently do. The most cost-effective and easily disseminated changes that can be made to a crop are changes to the genetics, as these are contained within the seed itself and, for many species, the seed is a pure breeding, self-replicating, resource.

Effect of a novel edible composite coating based on gum arabic and chitosan on biochemical and physiological responses of banana fruits during cold storage.

The composite effects of gum arabic (GA) (5, 10, 15, and 20%) and chitosan (CH) (1.0%) on the biochemical and physiological characteristics of banana fruits stored at 13 ± 1 °C and 80 ± 3% relative humidity (RH) for 28 days and afterward for 5 days at simulated marketing conditions (25 °C, 60% RH) were investigated. Significant (P ≤ 0.

Use of quantitative PCR to understand within-host competition between two entomopathogenic fungi.

Interactions between the entomopathogenic fungi Zoophthora radicans and Pandora blunckii infecting larvae of Plutella xylostella were investigated. This is the first report to quantify within-host growth of one fungus in the presence of another competing for the same host resource using quantitative PCR (qPCR) at regular time points during the infection process. In larvae inoculated only with Z.

Competition and co-existence of Zoophthora radicans and Pandora blunckii, two co-occurring fungal pathogens of the diamondback moth, Plutella xylostella.

The entomopathogenic fungi Zoophthora radicans and Pandora blunckii co-occur in field populations of Plutella xylostella and, therefore, are likely to interact during the infection process. We have investigated the possible outcomes of these interactions in the laboratory. Using four isolates, two of each fungal species, inter-specific interaction experiments were done in Petri dishes and on intact plants.

Intraguild interactions between the entomopathogenic fungus Pandora neoaphidis and an aphid predator and parasitoid at the population scale.

The interactions that occur between the entomopathogenic fungus Pandora neoaphidis and a predator (Coccinella septempunctata) and a parasitoid (Aphidius ervi) were assessed in microcosm and polytunnel experiments. Transmission of P. neoaphidis to the pea aphid, Acyrthosiphon pisum, was enhanced in the presence of both C.

Development of species-specific diagnostic primers for Zoophthora radicans and Pandora blunckii; two co-occurring fungal pathogens of the diamondback moth, Plutella xylostella.

Species-specific primers for Zoophthora radicans and Pandora bluckii were developed. To achieve this, partial sequences of DNA that encode for rRNA, more specifically, the ITS region (rDNA-ITS) were obtained from different isolates and analysed. Seven Z.

Immunolocalization of deformed wing virus particles within the mite Varroa destructor.

Deformed wing virus (DWV) induces wing deformation when bees are infected during their pupal development. Field observations and laboratory experiments suggest that the mite Varroa destructor is a vector of the virus. Moreover, it has been stated that DWV replicates within this mite.

Phenolic content and antioxidant capacity of hybrid variety cocoa beans.

Cocoa (Theobroma cacao L.) is a major, economically important, international crop and has been associated with several nutritional benefits including high antioxidant capacity. New cocoa hybrids have been developed in Ghana that exhibit resistance to pest damage during storage.

Behavioural responses of Tribolium castaneum (Herbst) to volatiles identified from dry cocoa beans.

New hybrid types of cocoa beans are attractive to insects in storage, however some of the insects feed little, if at all, on these beans compared to those of the traditional type (mixed genotypes). Based on a sniffing test using GCMS, differences in flavour volatiles in these types of beans have been determined and from these, six major volatiles of cocoa beans were selected for olfactometric analysis using a Pettersson olfactometer to determine which of them contributed to the attraction of Tribolium castaneum (Herbst) to the cocoa beans. The behaviour of Tribolium was affected by dose of 2-phenyl ethanol, acetophenone, 3-methyl butyraldehyde, ethyl butyrate, ethyl 3-hydroxybutyrate and butyl 2-methacrylate.

The growth of Tribolium castaneum (Herbst) and Lasioderma serricorne (Fabricius) on feed media dosed with flavour volatiles found in dry cocoa beans.

Acetophenone, ethyl butyrate and 2-phenyl ethanol were used as additives to media on which Tribolium castaneum (Herbst) and Lasioderma serricorne (Fabricius) were cultured for 65 days. Acetophenone and ethyl butyrate had a positive impact on the weight and multiplication of the insects. The weight and rate of multiplication was higher in feed media containing acetophenone alone.

Effect of fungal infection on the reproductive potential of aphids and their progeny.

The effect of infection by Pandora neoaphidis and Beauveria bassiana on the reproductive potential of the pea aphid, Acyrthosiphon pisum, and their progeny was assessed. Infection by either P. neoaphidis or B.

Pandora neoaphidis transmission and aphid foraging behaviour.

Pandora neoaphidis is an aphid-specific entomopathogen that produces infective conidia. As aphid movement increases, so does the likelihood of contact with conidia. Volatile distress signals released in response to aphid infestation as an indirect defence against herbivory may affect aphid foraging and, therefore, the fungus-aphid interaction.

Response of the entomopathogenic fungus Pandora neoaphidis to aphid-induced plant volatiles.

We used a model plant-aphid system to investigate whether the aphid-specific entomopathogenic fungus Pandora neoaphidis responds to aphid-induced defence by the broad-bean plant, Vicia faba. Laboratory experiments indicated that neither in vivo sporulation, conidia size nor the in vitro growth of P. neoaphidis was affected by Acyrthosiphon pisum-induced V.

Effect of spatial heterogeneity on the role of Coccinella septempunctata as an intra-guild predator of the aphid pathogen Pandora neoaphidis.

The foraging behavior of starved and non-starved adult and larval Coccinella septempunctata on groups of plants in the presence of Pandora neoaphidis-infected Acyrthosiphon pisum, uninfected aphids or a mixture of these two prey types was compared. In general results of these studies confirmed the results of previous work comparing foraging behavior on a smaller spatial scale in Petri dishes. However, behaviors were modified in response to spatial complexity, prey quality, and the host plant.

Laboratory evaluation of temperature effects on the germination and growth of entomopathogenic fungi and on their pathogenicity to two aphid species.

As part of an approach to select potential mycoinsecticides for aphid biocontrol, we investigated the effects of temperature on the growth, germination and pathogenicity of some hyphomycete fungi. Commercially available mycoinsecticides (based on Beauveria bassiana (Balsamo) Vuillemin and Verticillium lecanii (Zimmermann) Viegas) and other isolates of B bassiana, V lecanii, Metarhizium anisopliae (Metschnikoff) Sorokin and Paecilomyces fumosoroseus (Wize) Brown & Smith were evaluated. The rate of in vitro conidial germination of all isolates was slower at 10 and 15 degrees C than at 20 and 25 degrees C.

Effects of fungal infection on the alarm response of pea aphids.

Pea aphids (Acyrthosiphon pisum, Homoptera: Aphididae) infected with the fungal pathogen Erynia neoaphidis (Zygomycetes: Entomophthorales) were less sensitive to the aphid alarm pheromone (E)-beta-farnesene than uninfected aphids. Approximately 83% of the healthy aphids and 45% of the infected aphids (2 and 3 days post-inoculation) responded to the alarm pheromone. The percentage of nonresponding aphids increased as the disease progressed.

Implications of predator foraging on aphid pathogen dynamics.

The foraging behavior of starved and nonstarved second and fourth instar Coccinella septempunctata larvae on dead Acyrthosiphon pisum aphids, either infected with the entomopathogenic fungus Erynia neoaphidis (sporulating) or uninfected, was examined. Larvae searched for longer and fed less when presented with infected rather than uninfected A. pisum.