Rhizopus head rot Rhizopus arrhizus = Rhizopus nodosus Rhizopus microsporus Rhizopus stolonifer = Rhizopus nigricans. head rot, and Rhizopus head rot. Sclerotinia head rot. Download DOWNLOADS. Robert M. Harveson, University of Nebraska--Lincoln Follow. Sclerotinia basal stalk rot and wilt, mid-stalk rot, head rot Sclerotinia sclerotiorum = Sclerotinia libertiana = Whetzelinia sclerotiorum. R. stolonifer, R. oryzae (syn. Head rot disease is caused by several species in the genus Rhizopus, including R. stolonifer, R. arrhizus, R. oryzae, and R. microsporus. Rust Puccinia helianthi Puccinia xanthii Uromyces junci. Plants are virtually immune to infection at The results revealed that Head rot, caused by one or more species of Rhizopus, occurs sporadically, causing rotting and shredding of the head similar to Sclerotinia head rot. The disease is common on … This NebFact discusses the increase in sunflower production and the potential for diseases. The Rhizopus head rot pathogens require free moisture and a wound to successfully infect sunflower heads. Rhizopus head rot is caused by various fungi in the genus Rhizopus, including R. arrhizus, R. stolonifer, and R. microsporus. Authors. The sunflower cultivars were inoculated by R. stolonifer at two different growth stages (R5.7 and R6.0) of sunflower. ... Abstract. The affected heads turn brown and mushy, and then brittle and hard as they dry out. Included in. Rhizopus head rot has been reported from several areas of sunflower production in the world, including Australia, South Africa, and Mediterranean areas in Europe and India. Rhizopus head rot is a common and often severe fungal disease of sunflowers primarily in the high plains of the USA. The disease appears first as dark spots on the back of ripening heads. These species may occur singly or in a Wet weather following flowering is conducive to Rhizopus head rot. In the United States, Rhizopus head rot has historically caused only minor and localized damage to sunflowers. Rhizopus head rot is more serious in southern sunflower production regions including Kansas, Nebraska, Colorado, and the Texas Panhandle. These fungi are cosmopolitan in soil and decaying organic matter. NF00-426 Rhizopus Head Rot of Sunflower. Rhizopus head rot. Sunflower crops grown in Nebraska are susceptible to diseases caused by bacteria, viruses and nematodes, but the most economically damaging is head rot, caused by the fungal pathogen Rhizopus. AUTHORS: Sam Markell, Tom Gulya, Charlie Block and Bob Harveson. This 2007 NebGuide discusses the pathogen, disease history, symptoms, and management. R. arrhizus) and R. microsporus. Since June 17, 2009. Sclerotinia sclerotiorum. Rhizopus Head Rot. Rhizopus Head Rot of Sunflower in Nebraska G1677 Sunflower crops grown in Nebraska are susceptible to diseases caused by bacteria, viruses, and nematodes, but the most economically damaging is head rot, caused by the fungal pathogen Rhizopus. While both are widely distributed, white mold is a more serious problem in northern production areas, such as North Dakota, South Dakota, and Minnesota. The Rhizopus head rot pathogens require free moisture and a wound to successfully infect sunflower heads. 2000. Date of this Version. FIGURE 4 – White mycelium and black sclerotia on the face of a skeletonized sunflower head. The objective of this study was to determine the effects of head rot disease on seed yield in eight sunflower cultivars. Rhizopus head rot is caused by various fungi in the genus Rhizopus, including R. arrhizus, R. stolonifer, and R. microsporus. Head rot caused by Rhizopus stolonifer reduces sunflower seed yield and quality. 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