The common smut of maize (corn smut, Ustilago maydis /DC/ Corda) can cause large economic losses in susceptible sweet corn hybrids as well. The protection against this pathogen is fundamentally based on prevention. Many methods to control corn smut have been recommended or evaluated, including crop rotation, sanitation, seed treatments, modific...ation of fertility, and biological control. In spite of these frequently mentioned control strategies, the host resistance seems to be the only effective method to manage common smut in those areas where Ustilago maydis is prevalent.
Corn smut disease is one of the most common maize diseases. In the previous years the disease lost from its importance, however nowadays it is becoming more and more important and widespread. The protection against it encounters great difficulties, therefore it is important to emphasize prevention and resistance based protection. The aim of the... research was to investigate under laboratory circumstances the resistance of Hungary’s most commonly cultivated maize hybrids to corn smut disease. Twelve species were investigated. We distinguished two susceptibility groups within the hybrids based on the investigated parameters. The results are intended to assist the protection against corn smut disease and to make a suggestion for the farmers so that they could apply more environmental friendly and economical production.
Coenological surveys were conducted in the Hortobágy National Park (Pap-ere and Zám-puszta) in May 2015 and 2016. During the tests,a total of 40 permanent plots were analyzed on grasslands grazed by extensive cattle (Hungarian Grey) and mixed genotype intensive cattle. The presence of plant species, percentages of... total coverage of species and vegetation cover were recorded. Two habitat types were chosen according to their moisture content: wet salt marsh meadow (Bolboschoenetum maritimi) and drier salt meadows (Beckmannion eruciformis).
We compared the impact of increased number of animals (2016 years) and the low number of animals (2015 years, initial state) and the grazing exclusion on vegetations.
We tested: (i) what is the impact of grazing on the vegetation, (ii) how do species composition and vegetation charachteristics differ in the two habitat types (iii) and is there a difference in the impact of different cattle breeds (Hungarian gray, intensive beef cattle) grazing on the grasslands species composition? During the investigation we found, (i) that the greatest number of species was recorded in 2015, on the area that received moderate to intensive grazing (14.3 species per m2). Somewhat the number of species was reduced in 2016 due to more intensive grazing. The control group had the lowest number of species (11.7 species per m2). The undergrass and legumes cover significantly increased on intensive grazed lands. (ii) Our results indicate that the effects of different grazing differ in the two studied habitat types. On the drier grasslands greater number of species were found (16.2 species per m2), oppositely to the wet grassland (11.2 species per m2). The cover of the undergrasses was higher in the drier habitat than in the wet. (iii) The extensive beef cattle left a bigger number of species (16 species per m2) than the intensive beef cattle (11.4 species per m2). The grass cover was more intense on areas grazed by intensive cattle. The absolute and potential weeds cover showed a higher value on areas grazed by Hungarian Grey. Our two-year results suggest that grazing by both extensive and intensive cattle breeds can be a proper tool for the conservation management of alkali grasslands.
The leaf chlorophyll content analysis is important for several reasons. The natural or anthropogenic stressors directly effect on the chlorophyll content. Through the measurement of the chlorophyll content it is possible to obtain data concerning the physiological status of the plant, moreover the chlorophyll content is closely related to the n...itrogen content, so it is linked to photosynthesis and the photosynthetic activity which determine biomass production.
One of the most common symptoms of plant diseases is the larger and smaller interveinal chlorotic areas. These might be local, or expand to the whole plant. There are multiply reasons of chlorosis such as reduction of chlorophyll content, unfavorable effects on the chlorophyll content,disorders regarding function of chloroplasts or ultimately destruction of the chloroplasts. Although such a chlorotic deviancy can contribute to significant losses in photosynthesis; however the underperformance photosynthesis of the sick plants is a more complex process.
As we unambiguously experienced during our investigations on common smut that the infected maize plants most common accompanying symptom was chlorosis on the leaves, so it is especially important to examine how the infection influenced on the chlorophyll content of different hybrids.
Corn smut disease (Ustilago maydis) is one of the most common maize diseases. In the previous years the disease lost some from its importance, however nowadays it turns into more and more important and widespread one. The control encounters great difficulties, therefore it should be emphasized the preventive and resistance-based protection.
Common smut disease of maize is one of the most frequent diseases of crop. In the last decades the importance of disease has decreased in feeding maize production, however its importance increasing again nowadays, especially at sweet maize hybrids. The aims of this work was to find hybrids possess of resistance, and to evaluate which ones are m...ore or less susceptible under field artificial inoculation circumstances. Among feeding maizes the less susceptible hybrid was ‘P9578’, and the most susceptible ’NK Columbia’ hybrid, and differences in cob infection between them was significant (8.8%). At sweet corn hybrids the less susceptible was ’Prelude’, while the most susceptible was ’Jumbo’ with very high significant 74.6% differences.