fire blight is one of the most destructive diseases of stone and pome fruits. the causal pathogen is erwiniaamylovora, species in the family enterobacteriaceae. pears are the most susceptible, but apples, quinces and some other rosaceous plants are also vulnerable. in iran, the disease has been reported for the first time in baraghan in alborz province (zakeri & sharifnabi 1991). fire blight pr...

Background: There is a growing demand for mass production of shikalkin (a natural pigment consisted of shikonin and alkannin) due to its increasing applications in cosmetics, pharmaceutical and nutrition industries. The root of Iranian Arnebia euchroma produces shikalkin. The promising capability of this plant for shikalkin production has already been demonstrated in cell culture studies. Obje...

The retinal photoreceptors of a New World migratory bird, the bobolink (Dolichonyx oryzivorus) were examined using microspectrophotometry. Based on the absorbance spectra of their visual pigments and oil droplets, retinal photoreceptors include five classes of single cones, one double cone, and one rod. The single cones contain a long-wavelength pigment (lambda(max)=564nm) paired with a red or ...

Pinus pseudostrobus Lindl. is a species endemic to Mexico and widely used in reforestation programmes, as it highly adapted poor, shallow, limestone soils has high commercial importance. However, necessary preserve this genetic material since trouble due rates of deforestation, land use change, forest fires, so have effective strategies obtain good quality seedlings. Due the properties LED (lig...

Among the identified risk factors of age-related macular degeneration, sunlight is known to induce cumulative damage to the retina. A photosensitive derivative of the visual pigment, N-retinylidene-N-retinylethanolamine (A2E), may be involved in this phototoxicity. The high energy visible light between 380 nm and 500 nm (blue light) is incriminated. Our aim was to define the most toxic waveleng...

The present study is designed to evaluate the application of a simple method for rapid identification of Malassezia furfur among other Malassezia spp. based on production of a brownish-red pigment and its diffusion into the medium containing L-tryptophan as a sigle source of nitrogen.  91 strains of Malassezia (20% M. furfur, 2% M. sympodialis, 5% M. obtosa and 73% M. globosa) isolated from ski...

in order to detect hydrogen cyanide gene and to determine pseudomonas fluorescent efficiency in producing hydrogen cyanide for controlling the growth of rhizoctonia solanipathogen (the causal agent of sugar beet root and crown rot), samples were collected from sugar beet rhizosphere in sabzevar fields. after soil sampling and purification, 31 pseudomonas spp. isolates were separated on specific...