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.
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.
The authors of this study seek the answer to the question how to develop, in the first decade or decades of the 21st century, the university-level
horticultural scientific training, the horticultural innovation and the scientific co-operation between companies and universities in Debrecen and
in the North Great Plain Region and – in a w
of the prospects of past, present and future, they drew the following conclusions. The reconstruction of agriculture, horticulture and food industry
is a part of reforming Hungary's countryside. Horticulture, producing high added value, will be able to decisively contribute to the plan whereas
the value presently produced in an agriculturally cultivated area of 1,000 euros/hectare can reach 2,000 to 3,000 euros in the next two decades.
A necessary and indispensable precondition to achieving this is the strengthening of the innovation output of the Hungarian horticultural sector.
Despite the numerous technical criticisms formulated in connection with the serious problems of Hungarian agricultural and horticultural
scientific innovation, no progress has been made in this field for the past one and a half decade. The scientific research of this topic hardly
continued or did not continue at all, the up-to-date surveys and in-depth analyses were missing. The objective, basic principles and tasks of the
Act CXXXIV of 2004 (TTI) enacted concerning research-development and technological innovation are clear and progressive. The co-operation
between the National Research Technology Office and the Hungarian Academy of Sciences, the setting up of the Innovation Fund are heartening
opportunities. These – along with the new Higher Education Bill to be passed – may as well be suitable for restarting the Hungarian agricultural
and horticultural scientific innovation. In our opinion, this requires a new, well-considered national agricultural programme, which can be
conceived in the framework of the "Ferenc Entz National Horticultural Plan" proposed by us for horticulture. In the most eastern Hungarian
university knowledge centre, at the University of Debrecen, the continuing of the horticultural scientific innovation strategy started in the last
decade may be the focal point and generator of the development of the so-called "Hungarian Horticultural Triangle”, or "Hungarian
Horticultural Cluster". This region comprises the Northern and Southern Great Plain Regions and the area between the Danube and Tisza
Rivers. Here, about 70 to 75% of the total Hungarian horticultural commodity stock is produced. The objective of the HORT-INNOTECH
DEBRECEN programme planned in 2004 by the University of Debrecen, Centre of Agricultural Science is to establish the horticultural scientific
research-development and technological innovation structure and knowledge base of the Hungarian Horticultural Triangle / Hungarian
Horticultural Cluster. In harmony with this, the objectives are to bring about competitive, new horticultural products, to improve the conditions
of utilising them, to enhance the competitiveness of enterprises based on technological innovation, to make use of the research-development and
innovation opportunities available in the regions in an efficient manner, to as full extent as possible, to encourage the creation of places of
employment producing high added value in the field of horticulture, to improve the technical skills of those employed in horticultural researchdevelopment and to promote their enhanced recognition by the society.
The amounts of Fe, and Zn were measured in maize seedlings infected by smut gall tumour (Ustilago maydis Dc. Cda.) and in healthy seedlings five days after infection. The amount of elements was also measured under different stress intensities. Due to the infection, as a biotic stress, the amount and distribution of examined elements have been c...hanged. On the bases of the differences in the Fe distribution between the symptoms less and tumorial leaf parts, we have come to the conclusion that the infection also effects the mobilisation of Fe and Zn inside the plants. The Fe uptake was much higher in the infected plants and the tumour development also had an effect on the uptake and distribution of the examined elements. The experiments of infecting maize seedlings by monosporidial strain of crown gall tumour showed no tumour development. We found that the monosporidial strain also acts as a biotic stress and has an effect of iron and zinc distribution. We observed a slight difference in the iron and zinc contents in the roots of corn seedlings infected by different monosporidial sporidium concentrations, while the iron and zinc contents in the shoots were increased by the intensity of the infection. The roots do not form tumours. There is no difference between the roots of the infected and healthy corn seedlings. Since the Fe and Zn contents of the shoots of infected plants depend on the intensity of the infection, we have come to the conclusion that there must exist a „special” communication system regulating the transportation of the examined elements.
In the experiments with infected maize seedlings, it became necessary to get the iron chlorosis before the disease reaches the lethal phase. Although most of the iron reserves are located in the embryo, to accelerate the chlorosis, the endosperm was removed, and it was observed, that the iron chlorosis appears later in maize seedlings when the endosperm is removed. The relative chlorophyll content of the first and second leaves was measured in iron efficient and iron deficient maize seedlings at different times.
The higher IAA content of tumorial plant tissues is already known. The treatment with IAA decreases the iron concentration in the shoots and in the roots of +Fe precultured plants and increases at -Fe precultured ones. The TIBA retards the shoot-to-root transport of IAA. When the seedlings were treated simultaneously with IAA and TIBA, higher iron concentrations were observed in the shoots and in the roots of corn seedlings.
We found extremely high iron concentrations in the roots of infected seedlings and, in line with this, serious damage to the roots was observed that this can be caused by the high iron content generated free radicals. The results demonstrate that IAA has a role in the shoot to root communication.