Pre-flowering low temperature predisposition of sorghum to sugary disease (Claviceps africana)

• Published in: Journal of phytopathology Vol. 135; no. 4; pp. 328 - 334
• Main Authors: McLaren, N.W. (Grain Crops Research Institute, Potchefstroom (South Africa)), Wehner, F.C
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.08.1992; Blackwell
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; CLAVICEPS; Claviceps africana; Fundamental and applied biological sciences. Psychology; Fungal plant pathogens; Fungi; Getreide; Pathology, epidemiology, host-fungus relationships. Damages, economic importance; Phytopathology. Animal pests. Plant and forest protection; REPONSE DE LA PLANTE; RESISTANCE AUX MALADIES; RESISTENCIA A LA ENFERMEDAD; RESPUESTA DE LA PLANTA; SORGHUM BICOLOR; Spezifitaet; Suedafrikanische Republik; Temperatur; TEMPERATURA; TEMPERATURE; South Africa; Africa; Monocotyledones; Thermal factor; Cold; Mycosis; Night; Plant pathogen; Environmental factor; Cereal crop; Field experiment; Fungi; Infection; Sorghum bicolor; Genotype environment interaction; Gramineae; Angiospermae; Predisposition; Male sterility; Minimum temperature; Ascomycetes; Spermatophyta; Greenhouse study; Thallophyta
• ISSN: 0931-1785; 1439-0434
• DOI: 10.1111/j.1439-0434.1992.tb04318.x

The relationship between pre-flowering climatic conditions and sugary disease incidence in sorghum was quantified over two seasons. In field trials with three male normal genotypes, low night temperatures 3-4 weeks prior to flowering increased susceptibility to the disease. Average night temperatures of below 12 degrees C during the critical period resulted in male-normal genotypes being as reduced, suggesting that increased susceptibility was the result of low temperature induced sterility. Genotypes differed in their ability to tolerate pre-flowering cold stress. Greenhouse and growth chamber trials confirmed that cold stress applied 7-8 weeks after planting reduced pollen viability and that this was the primary reason for increased susceptibility to sugary disease