wheat is grown on 6.2 million hectares under different agr-climate conditions in iran. of 6.2 million hectares irrigated wheat, khazar warm humid climate regions (gorgan, mazandaran and moghan) with 350 thousand hectares are the most important wheat growing areas of the country. productive and rich lands, high rainfalls and favorable temperature and light in these regions provide good condition...

Plant diseases have become an important issue because they cause important reduction in each quality and amount of agricultural products. Automatic detection of plant diseases is an important analysis topic because it could significantly help in observation giant fields, and enable automatic detection the symptoms of diseases as soon as they appear on the plant leaves. In this paper an algorith...

A digital image analysis method previously used to evaluate leaf color changes due to nutritional changes was modified to measure the severity of several foliar fungal diseases. Images captured with a flatbed scanner or digital camera were analyzed with a freely available software package, Scion Image, to measure changes in leaf color caused by fungal sporulation or tissue damage. High correlat...

During 2000 and 2001, the prevalence of fungal diseases of alfalfa was surveyed underenvironmental conditions in Zanjan province, Iran. In total, 15 genera of fungal pathogens wereisolated from plants sampled from the fields. All of these disease interactions had not been previouslyrecorded in Zanjan and Colletotrichum truncatum, Leptotrochila medicaginis, Phoma medicaginis,Rhizoctonia crocorum...

Overview Each year the commercial carrot crop in Wisconsin suffers losses from alternaria leaf blight, cercospora leaf spot, and aster yellows. The first two are diseases caused by fungi (Alternaria dauci and Cercospora carotae). The third is a disease caused by the aster yellows phytoplasma, a parasitic bacterium of carrot phloem tissue and also of the aster leafhopper (Macrosteles quadrilinea...

Since ancient time plants have been used as source of therapeutic agents, plants play a significant role in the indigenous system of medicines to combat diseases. Plants are richest source of bioactive organic chemicals on earth. Phytochemical properties of leaf of Calotropis procera obtained from methanol and petroleum ether extracts were investigated .The results suggest that the Phytochemica...

Rhizoctonia sheath diseases of rice, comprising sheath blight, sheath spot and aggregate sheath spot, cause significant yield losses in many rice-growing regions of the world. The emergence of Rhizoctonia sheath diseases as economically important rice diseases is of recent date and has been attributed to the intensification of rice-cropping systems with the development of new short-stature, hig...

By the end of the 1980s, black leaf streak disease caused by Mycosphaerella fijiensis was present in all continents where bananas or plantains were grown, although distribution in some regions was limited to a few countries. In this presentation, the spread of the disease during the 1990s in several countries and regions, and the important socio-economic consequences are discussed. From 1990 to...