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Breeding and quality traits of cereals at the State Stende Plant Breeding Station
1998
Kalinina, K. (State Stende Plant Breeding Station, Dizstende (Latvia))
The State Stende Plant Breeding Station was founded in 1922. The basic tasks of State Stende Plant Breeding Station are: to produce and introduce in production the winter and spring wheat, malting barley and oats varieties with high yielding, lodging and disease resistance, good quality acceptable to Latvian climatic conditions. Research work has been done in 7 groups and 3 laboratories: Winter Wheat Breeding Group; Spring Wheat Breeding Group; Barley Breeding Group; Oat Breeding Group; Cereal Growing Technology Group; Legume Growing Technology Group; Potato Seed Growing Group; Laboratory of Plant Pathology; Laboratory of Grain Technology; Laboratory of Agriculture Chemistry.
اظهر المزيد [+] اقل [-]Collar rot of peanut caused by Lasiodiplodia theobromae النص الكامل
1998
Phipps, P.M. | Porter, D.M.
In August and September of 1993, a collar rot disease of peanut was observed in several fields in Virginia and North Carolina. Only a few scattered plants exhibited symptoms and signs of the disease in Southampton County and Suffolk, Virginia, and Northampton County, North Carolina. The disease was severe at two farm sites in Dinwiddie County, Virginia where the affected areas exceeded 0.4 ha in size. Numerous plants were either chlorotic, wilted, or dead. Symptomatic plants exhibited blackened stem cankers and pods. Diseased stems and tap roots were easily shredded to reveal slate-gray to black internal tissues. Black, erumpent pycnidia were observed on stem lesions at the soil surface. Immature conidia were single-celled and hyaline. Mature conidia were two-celled and dark brown. Morphological features of the fungus on diseased plants and potato dextrose agar were consistent with descriptions of Lasiodiplodia theobromae (Diplodia gossypina). The fungus was isolated from discolored seed and asymptomatic seed from fields having plants which exhibited severe symptoms. Seed treatment with captan 1.125 g + pentachloronitrobenzene 0.375 g + carboxin 0.25 g a.i./kg reduced recovery of the fungus from seed, but did not eradicate the pathogen. This treatment on naturally infested seed provided significant early-season disease suppression and improved yield significantly in 1994. Season-long disease suppression and a significant yield increase were obtained in plots planted to fungicide-treated, commercial seed from non-infested fields. At-plant and mid-season applications of fungicides in 1994 and 1995 did not improve disease suppression over that of fungicide-treated, commercial seed. Overall, Virginia-type cultivars of peanut were more susceptible to collar rot than runner-type cultivars. Among the Virginia-type cultivars, NC-V 11 exhibited moderate susceptibility and the 79-X breeding line from Florida exhibited resistance. Georgia Browne and Southern Runner were the most resistant of the runner-type cultivars.
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