In this study, antifungal activity of essential oils of Cymbopogon citratus and Ocimum basilicum and two fungicides Mancozeb and Metalaxyl-Mancozeb in six different concentrations were investigated for controlling three species of Phytophthora, including P. capsici, P. drechsleri and P. melonis on pepper, cucumber and melon under in vitro and greenhouse conditions, respectively. Under the in vi...

Cocoa (Theobroma cacao L.) is a commodity produced in the developing countries of the tropics. It is mainly consumed in the middle and high income countries of the world’s temperate zone. Currently, over 50 countries are engaged in cocoa production and heavily rely only on cocoa exportation for their economic development, as this commodity contributes significantly to foreign exchange earnings....

A technique for inoculation with precise numbers of fungal spores on leaves and stems of plants was developed. The technique consisted of placing 1-μl drops with a fixed number of spores on the surface of leaves and stems, and covering each inoculum drop with a 10-μl drop of low-temperature gelling SeaPlaque agarose to fix the inoculum on the target site. With this technique single zoospores of...

Loss of heterozygosity (LOH) occurs in a variety of diploid organisms after chemical mutagenesis and was observed in the vegetable pathogen Phytophthora capsici after N-ethyl-nitrosourea (ENU) mutagenesis at three loci during reverse genetic screening. Our objectives were to determine (i) the frequency of LOH among mutants, (ii) the directionality of the LOH events and (iii) the length of the g...

Pyrimorph is a novel fungicide with high activity against the plant pathogen Phytophthora capsici. We investigated the risk that P. capsici can develop resistance to pyrimorph. The baseline sensitivities of 226 P. capsici isolates, tested by mycelial growth inhibition, showed a unimodal distribution with a mean EC(50) value of 1.4261 (± 0.4002) µg/ml. Twelve pyrimorph-resistant mutants were obt...

Phytophthora capsici is an oomycete that causes various symptoms, such as root, neck, stem, fruit rot, and leaf blight, in different plant species, including the genus Capsicum. One of tools to counteract this biotic problem, which may be more profitable respectful environment long term, using biocontrollers Bacillus, Pseudomonas, Streptomyces (bacteria), Trichoderma (fungus). It seems each the...

Phytophthora capsici and P.parasitica were transformed to hygromycin B resistance using plasmids pCM54 and pHL1, which contain the bacterial hygromycin B phosphotransferase gene (hph) fused to promoter elements of the Ustilago maydis heat shock hsp70 gene. Enzymes Driselase and Novozyme 234 were used to generate protoplasts which were then transformed following exposure to plasmid DNA and polye...

Fruit and vegetable growers continually battle plant diseases and food safety concerns. Surface water is commonly used in the production of fruits and vegetables and can harbor both human- and plant-pathogenic microorganisms that can contaminate crops when used for irrigation or other agricultural purposes. Treatment methods for surface water are currently limited, and there is a need for suita...

The potential for oxathiapiprolin resistance in Phytophthora capsici was evaluated. The baseline sensitivities of 175 isolates to oxathiapiprolin were initially determinated and found to conform to a unimodal curve with a mean EC50 value of 5.61 × 10(-4) μg/ml. Twelve stable oxathiapiprolin-resistant mutants were generated by fungicide adaptation in two sensitive isolates, LP3 and HNJZ10. The f...