We provide evidence for structural and detoxification-related mechanisms … On hybrids with race-specific resistance, lesions are small and yellow and produce no spores (Figure 4). Keywords: Gray leaf spot, Grey leaf spot, GLS, Cercospora, QTL, Maize, Corn Background Gray leaf spot (GLS) is a foliar disease of maize that was highlighted as a threat to maize production in the USA in the 1980s [1], reported in South Africa in the 1990s [2], and currently has a worldwide distribution in maize Key words: Maize, Zea mays, grey leaf spot, grain yield, combining ability. Maize (Zea mays L.) is one of the important food crops for human and animal in Egypt as well as in the world. It has become well established in the province of KwaZulu-Natal, and is capable of reducing grain yields by 20 to 60%. Until the middle oft the 90s leaf blight of maize was considered to be a problem of warm humid maize growing areas as in our neighbouring countries in the south and overseas. Lesions start as small yellowish spots that latter turn dark-purple to black, oval spots usually occur on the midribs of leaves 2. Diplodia Leaf Streak (Stenocarpella macrospora) SyMptoMS: Symptoms of Diplodia leaf streak can occur on all leaves including the ear leaves. Lesions are large (up to 10 cm long), gray-green and elliptical with a water-soaked appearance. Not only is it a threat to maize 1. The disease is now recognised as one of the most significant yield-limiting diseases of maize worldwide and certainly in the province of KwaZulu-Natal (see Table 1). Holcus leaf spot is not known to spread from infected leaves to healthy leaves, and lesions are typically larger than lesions caused by Curvularia leaf spot. Dark-purple, round spots may also occur on leaf sheaths, stalk, and sometimes on the outer ear husks and tassels of maize Management and Control 1. Symptoms of eyespot are very similar to Curvularia leaf spot symptoms. Brown spot lesion s fir st appear as very small, rou nd-to-ob long, y ellowish spots on the leaf blade (Figure 1) , leaf she ath (Figu re 2), st alk, and r arely on the husks and tassel of the outer ear. Figure 2. Turcicum leaf blight is ubiquitous in hill environments and can cause severe losses if the variety does not have good genetic resistance. Similaarly, gray leaf spot disease is emerging as problematic during rainy NCLB lesions may also appear on the leaf sheaths and husks of susceptible hybrids. The occurrence of this disease is recorded for the first time in the country in 2006. ABSTRACT Grey leaf spot is a relatively new fungal disease of maize in South Africa. Banded leaf and sheath blight (Rhizoctonia solani) was increasing in severity and prevalence in all environments. The local maize breeders could now incorporate the genes for GLS resistance in CML 373 and TZMI 711 and the grain yield genes in CML 384 into elite lines using recurrent and backcross methods, respectively in order to increase maize production and productivity in Kenya. Gray leaf spot (GLS) is an important and destructive disease of maize in the hills of Nepal. GREY LEAF SPOT OF MAIZE by Dr Julian Ward Introduction Grey leaf spot (GLS) of maize is caused by the fungus Cercospora zeae-maydis. Northern Corn Leaf Blight Purdue extension lesions, and fewer fungal spores. Grow Seed Co tolerant hybrids 2. The disease is spreading to neighbouring provinces and are splashed or wind-blown to upper leaves or to other plants. The spots may occur in bands across the leaf blade. Infected tissues tur n a choc olate br own to re ddish See University of Kentucky Extension Publication, Holcus Leaf Spot (PPFS-AG-C-06), for more information. 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