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  • Mass occurrence of a Phoma-like fungus on common ragweed (Ambrosia artemisiifolia) in Hajdúság region, East Hungary
    55-60
    Views:
    233

    Common ragweed (Ambrosia artemisiifolia L.) is one of the most important, allergenic weed species in Hungary. A. artemisiifolia invades both a broad range of often disturbed areas (brownfields) and either undisturbed ones like waste lands, roadsides, riverbanks and railway tracks. In field crops it can cause considerable yield losses mainly in sunflower, maize, cereals and soybean. In Hungary many inhabitants suffer from allergy caused by Ambrosia pollen which results a serious human-health risk. The aim of the control is to prevent flowering and seed propagation of A. artemisiifolia. Until now the occurrence of numerous pathogenic fungi which attack common ragweed plants have been identified in Hungary, however there is not yet available biological weed control program because of shortage in acceptable effectiveness, and endangering cultural plant species. During our weed surveys in the region of Hajdúság (East-Hungary) we found numerous common ragweed plants showing heavy necrotic lesions on leaves and stems. The objective of this study was to identify the fungus which was isolated from diseased tissues of common ragweed (A. artemisiifolia). The identification of fungus based on morphological characters of colonies and features of conidia and chlamydospores developed on malt extract agar (MEA) plates. After examination of axenic cultures we revealed that the fungus isolated from the leaves ands stems of common ragweed was a Phoma-like species.

  • The effect of water supply and crop year on the yield potential of sweet maize (Zea mays L. convar. saccharata Koern.) hybrids with different genotypes
    203-210
    Views:
    201

    The successfulness of crop production is significantly affected by not only the the average yields that provide cost effectiveness, but also the success of striving for yield safety, therefore, varieties and hybrids tolerant to environmental stress factors are worth being included into the sowing structure. Our aim was to further the decision making of producers in prepaering the right sowing structure by the evaluation of sweet maize hybrids’ tolerance to excess rainfall.
    We performed our examinations in an extremely wet year (2010) on chernozem soil on three sweet maize hybrids (GSS 8529, GSS 1477, Overland) in 12 replications. Comparing the yields of 2010 with those that can be expected under optimal rainfall conditions, we showed that the examined hybrids react to the amount of rainfall higher than their needs with yield depression. The excess rainfall tolerance of the examined hybrids is different in the case of each hybrid.

  • Developing vegetable and fruit marketability potentials in Hajdu-Bihar county in terms of Hungary’s EU accession
    60-69
    Views:
    92

    prearrangement, Hungary will be ready to join the EU by the 1st of January 2003. In the course of negotiations, the Government places special emphasis on agriculture, because Hungary is an agrarian country. Agricultural production is an important economic factor in Hungary: larger a factor in its economic structure than in those of the present EU member-states. In order to preserve competitiveness, Hungarian farmers and its
    processing industry require information on the EU's CAP and other market influences.
    In Hajdú-Bihar county the quality of agricultural products fall behind the standards of the European Union. There is no real solidarity among farmers, so they are left alone and are unable to meet higher, those standards, which were introduced by the structural changes of the market. Unfortunately, there is only one fruit and vegetable marketing organization (PO) in the county, although its necessity and effectiveness has been proved several times.
    Within the framework of Rural Development, agricultural marketing is vital, because together with the local FVM institutes, it can help the farmers by providing consultation, information, and by marketing their products. Since fruit and vegetable growing has a considerable history in Hajdú-Bihar county, marketing activities can be effective in assisting both the farmers and the processing industry in preparation for EU integration.

  • Production technology development of millet at different ecological conditions
    63-67
    Views:
    167

    The millet is a very special plant with good adaptation that gives the possibility for the late sowing and secondary production. However the effects of late sowing modifies the efficiency of the agrotechnological elements. The exainations – focused on this aspect – was conducted in the DU RINY and DU RIK in small plots in four replications in 2014. Among the examined factors (sowing time, nutrient supply, growing area) sowing time had the largest effect. The effectiveness of the agrotechnological elements decreases under unfavourable circumstances caused by the late sowing.

    The agrotechnical elements modifies the yields in the examined genotype. Sowing time had the biggest effect on the yields of millet. The genotype „Maxi” had the highest yield in the different treatment variations.

    The yield differences were significant between the sowing time and plant density variations, but the nutrient supply had not significant effect (the rate of precipitation was unfavourable in 2014 season).

  • New methods of compost homogeneity determination in sewage sludge based compost prisms
    49-52
    Views:
    183

    There is no effective method of homogeneity measurement of compost prism. The most frequently used technology is the examination of the particle distribution. This method needs a lot of time and large number of samples. The aim of our research is establishing different effective methods to determine the homogeneity of compost prisms. During our work, we examined the homogeneity of a prism made of sewage sludge and saw-dust mixture.
    The measurements were based on the different properties of raw materials. According to this we examined the homogeneity by moisture content, heavy metal content and gas distribution measurements.
    The most effective method is the measurement of gasconcentration. Although gas-concentration measurements it need special equipment it has more advantages than the other methods. The examination of gas-distribution compensates the problem of sampling because the measurement is direct. It provides the opportunity to estimate the amount of emitted toxic gases and to determine the maturity of the compost and the effectiveness of the degradation.

  • The management and economical aspects of GPS based machine-control and tractor-implement sincronisation
    161-167
    Views:
    207

    Precision farming has an array of technological equipment, elements and complete systems which are in themselves suitable to create conditions for efficient farming, to reduce environmental load and to provide farmers with optimal return on their investment.

    On the leading edge of my research is to introduce the economic benefits of precision logistic optimization with satellite navigation in wheat and maize harvesting. My hypothesis, claiming that a well-organized system can increase the number of working days by 4 days per harvesting season in maize, and 2 days in wheat crop. If the farmer makes contract works for harvesting it means for him 2 or 4 days extra work by using the precision farming technologies with satellite communication system. Overall, as pertains to wheat and maize harvest seasons, yearly revenues can be increased by 7 760 000 HUF. I would like to introduce that the precision technologies increase combine costs by merely 5.4% which can be return in the first year of using.

  • Possibilities of downsizing sweet cherry trees via growing techniques
    71-74
    Views:
    194

    By applying smaller crown sizes and intensive growing techniques, many advantages can be identified compared to the extensive orchards. Also, nursing/pruning and harvest work can be performed more effectively. The outer and inner quality parameters of the fruit and the effectiveness of plant protection techniques are improved. The smaller crown size enables us to apply technologies for ensuring yield safety (e.g. hail, rain, bird nets), resulting in an increase in productivity. The introduction of smaller trees poses a great challenge to cherry production. Trials with dwarfing rootstocks have not yet been successful, therefore, we must use the cv. Mahaleb rootstock, which is excellently adapted to the Hungarian conditions, and also has a stronger growth. In addition, rootstocks with such strong growth are needed for the necessary regeneration of the productive parts of cherry cultivars, there is a need for. At the research garden of the University of Debrecen in Pallag, we planted 21 cherry cultivars on cv. Mahaleb (CT500) rootstock, in a 4 m x 1 m spacing pattern, in the spring of 2000. In our study, we demonstrated the possibilities of developing and maintaining the string super spindle through repeated summer pruning, in terms of growth, bud and fruit formation,. Based on these parameters, we determined which cultivars are the most suitable for intensive production.

  • Study of animal welfare status in dairy cow herds in Hungary – looking for causes of lameness
    47-50
    Views:
    198

    In the last 20–30 years lameness in cattle was found to be third the most influential disease next to mastitis and reproduction disorders. Studies have been established to explore reasons for lameness and prevention. The problem with more robust prevention plans is that knowledge and research evidence is not strong enough to run an effective prevention plan. The aim of the research is to look for reasons of lameness by observing number of cows on 6 farms during 2 lactations. Performance data will be put together to body condition score (BCS) and lameness scores. Other examination is focused on monitoring of 40 farms. This part of the project is more related to extension, collecting and sharing solutions for decreasing lameness. Producers are advised what kind of measures are possible to reduce occurrence of lameness. Effectiveness of those actions will be measured at the end of the study. The first preliminary results show lack in almost all preventive measures needed to be taken in minimising lameness. Those areas are related to poor facilities, lack of straw, problems with labour and basic management.

  • Study on Human Resource Management in Agriculture
    171-181
    Views:
    93

    The human factor has been reassessed with regard to strategic initiatives towards obtaining and preserving competitive advantage. Knowledge, experience and special skills are a specific form of capital, forming part of the organisations’ assets and serving as an organisational strategic resource. Their development and use require major investments, both on the part of the individual and the organisation. In a Europe undergoing integration, the quality of human resources enjoy priority among our really important values and specific features. The opportunities of the near future can be utilised, and agricultural economic organizations can survive and increase their organizational effectiveness, if they possess a basis of human capital which is able to make a shift in perspective and behaviour which is of primary importance from the point of view of incorporating market mechanisms and implementing them in practice. My investigations were focused on the current position of human resource management in a comprehensive manner; further, on the approach of top managers regarding the future. Analysing the business and other indicators of the companies studied, I have set the objective to describe the differences and special features of the human resource management practice of companies, which are different in size, operational form, and from the perspective of success or failure.
    Human resource management is directed to attracting, retaining, motivating and utilising labour. A given work process can be successful or unsuccessful – given the same conditions – depending on who performs it. Therefore, human resource management related tasks require special attention when enterprises are planned, established and operated. On analysing the responsibilities of human resource management, I have found that the functions and responsibilities of human resource have low or medium importance in the operation of economic organisations today. Regarding the future, top managers have expressed higher expectations of human resource management responsibilities in all areas and they consider individual functions to be more important. The establishment and operation of a human resource information system has been presented as the most important need for change. Correlation analyses have proved that the higher the sales revenues of a company, the higher the development of human resources is regarded by its manager, and the same holds for training, career support and a proper establishment and continuous evaluation of job profiles.

  • An advanced classification method for urban land cover classification
    51-57
    Views:
    214

    This manuscript presents a detailed comparative analysis of three advanced classification techniques that were used between 2018 and 2020 to classify land cover using Landsat8 imagery, namely Support Vector Machine (SVM), Maximum Likelihood Classification (MLSC), and Random Forests (RF). The study focuses on evaluating the accuracy of these methods by comparing the classified maps with a higher-resolution ground truth map, utilising 500 randomly selected points for assessment.

    The obtained results show that, compared to MLSC and RT, the Support Vector Machine (SVM) approach performs better. The SVM model demonstrates enhanced precision in land cover classification, showcasing its effectiveness in discerning subtle differences in landscape features.

    Furthermore, using the precise classification results produced by the SVM method, this study examines the temporal variations in land cover between 2018 and 2020. The results provide insight into dynamic land cover changes and highlight the significance of applying reliable classification techniques for thorough temporal analysis with Landsat8 images.

  • Preliminary results on Siberian sterlet (Acipenser ruthenus marsiglii) fries rearing under intensive conditions
    27-31
    Views:
    135

    In our experiments production performances of Siberian sterlet were tested under intensive tank conditions. During the 25 days long experiment effectiveness of weaning to artificial diet of the fish was investigated. Production performances of fish fed on exclusively dry diet from the beginnings were lower than the other two groups. Between the values of sterlets fed on live food also then suddenly vs. continuously were weaned to dry diet there were no significant differences. Based on our results live food feeding could be suggested for the Siberian sterlet larvae for some days but the method of the weaning to dry diet has no significant influence to the production performances.

    In 21 days long experiment four different feeding frequencies were tested in Siberian sterlet (~13 g) fingerlings. Dry feed was offered for the fish continuously, 2, 3 and 4 times per day. There were no significant differences between the values of the four treatments. Based on our results there is no high influence of feeding frequency in case of this size group of Siberian sterlet.

    During the nursing in two different size groups of Siberian sterlet the optimal daily amounts of feed were aimed to determine. In case of growth values of the group fed at 7% of the total biomass were higher than the other two groups (3 and 5%). Feeding performances of fish fed at 5% were significantly better than fish fed at 7%. Based on our results for ~20 g size of the subspecies at least 5% of total body weight could be suggested.

    In case of ~150 g size of the fish the production performances of fish fed at 1% were lower than the other two groups (2 and 3%). Between the values of stocks fed at 2 and 3% there were no significant differences. Based on these results 2% of total body weight of dry feed could be suggested for the Siberian sterlet with ~150 g body weight.

  • Crop Load, Fruit Thinning and their Effects on Fruit Quality of Apple (Malus domestica Borkh.)
    29-35
    Views:
    376

    Crop load, a quantitative parameter used by industry, is generally defined as the number of fruit per tree. It is often expressed in terms of number of fruit per trunk cross-sectional area (fruit/TCSA). Crop load is the most important of all factors that influence fruit size, and the removing of a part of the crop is the most effective way to improve fruit size.
    The potential size of a given pome fruit is determined early in the season and growth proceeds at a relatively uniform rate thereafter. This uniform growth rate permits the accurate prediction of the harvest size of the fruit as early as mid-summer. The growth rate, once established, is not easily altered, and fruit numbers, therefore, can affect fruit size only within definite limits and maximum effectiveness requires adjustment in fruit numbers relatively early in the season. It was established, that „thinning does not change a potentially small fruit into a large fruit, but rather insures that a potentially large fruit will size properly.” Emphasis should be on estimating fruit numbers rather than fruit size.
    Fruit thinning can quickly reach the point of diminishing returns. Rather than a high percentage of large fruits, the objectives of thinning should be the elimination of the smallest fruits, improved fruit quality and annual production. Fruit thinning is accomplished by hand or chemical thinning. Chemical thinners are separated into categories as bloom thinners and post-bloom thinners. Early removal of potential fruit (blossom thinning) is currently used in many apple producing areas to enhance flower initiation for next year’s crop and thus, return bloom. It also results in reduced competition for photosynthates. Blossom thinners usually have a caustic effect on floral parts.
    The amount of fruit left on a tree should be determined by the vigor and general condition of the tree. Leaf area per fruit affects the number of spurs flowering the following season. It can be difficult to separate timing and fruit number effects in crop loading studies, as abscission rates after hand thinning of retained flowers/fruitlets tend to very with the time of hand thinning.

  • Alternatives of microclimate control in orchards
    209-212
    Views:
    174

    The aim of the study was to find out which of the methods used to avoid damages of late frosts would be the most effective for the fruit growing practice. We tested the antifrost irrigation method in Debrecen-Pallag. For that purpose microjet sprayers are used, which are thrifty and does not need for that purpose large containers. With the aim to secure an even distribution of water, the sprayers are distributed on three levels: above and inside of the crown as well as on the level of trunks. On a large scale, a single microjet above the crown level would be sufficient. By means of a detailed analysis  served to set the optimum intervals between spraying phases: with each 15, 10, 5 and 3 minutes during half a minute. The synchronous presence of water and ice below the freezing point, the released freezing heat plus the water used much above the freezing point
    (9–10 °C) altogether maintains the temperature above around 0 °C near the flowers or growing fruitlets, meanwhile, the surrounding air cools down to -8 °C. The effectiveness of the generally used antifrost would be increased substantially by the former application of cooling irrigation, which delays the blooming date. 

  • Study of Educational Motivation among Agricultural Managers
    161-170
    Views:
    107

    It is a priority for companies to utilise human resources as much as possible. The form and effectiveness of the utilisation of labour largely depends on how much the manager of the company and the human resource management area support and encourage labour to develop individually and work more efficiently – as far as the size of the company justifies and allows. Effective incentive methods have to be set and run. Training incentives will have to play an important part in the future.
    There has been no major difference between training incentives between managers and subordinates. Material incentives continue to be the key factor. For managers, exchange of information is currently a primary training incentive, as is the opportunity to meet other experts and exchange their ideas. Further, performance-related payment and bonuses applied jointly are also some material incentives. In the future, material incentives will gain in importance. For subordinates, the operation of material incentives is currently highly important as a training incentive. This is not expected to change in the future either, while expectations linked to quality work will strengthen.

  • Testing of paraffin oil efficiency against grape powdery mildew in Eger wine region
    73-80
    Views:
    410

    The aim of the present study was to examine the efficiency of paraffin oil against powdery mildew in Eger wine region. The experiment has been carried out in 2013 and 2014 with Chardonnay and Kékfrankos grape varieties, which have different resistance against powdery mildew. The effectiveness of the oil was examined on leaves and clusters (frequency and intensity). This oil was effective against Erysiphe necator infection on field trials in Chile and Brazil. The spread of downy mildew (Plasmopara viticola) was also inhibited by this material in some experiments conducted in Spain and France.

    The differences between oil treatments represented the sensitivity of the grape varieties in accordance with the applied dosages. The oil was effective against powdery mildew with different extent as a result of the so called ”vintage effect”. In 2013, the treatment of the highest dosage (D3) didn’t differed significantly in frequency and intensity of infection from the regular treatment (clusters of Kékfrankos, leaves of Chardonnay). In 2014, the oil was not so effective against powdery mildew compared to 2013. No remarkable differences were detected between the treatments due to the strong pressure of powdery mildew. Furthermore, no any effect of the lowest dosage (D1) was detected in the case of the sensitive clusters of Chardonnay and leaves of Kékfrankos in both experimental years.

    In summary, the oil treatment has an effect against powdery mildew, however this efficiency largely depends on the vintage characteristics and the pressure of powdery mildew. Further investigations are neccessary, for example field trials with combinations of other sprays. The oil can be useable as fungicide with proper care in eco-friendly integrated and bio (ecological) viticulture.

  • Findings on the cultivation of potatoes in organic farming
    113-116
    Views:
    101

    This paper explores the effectiveness of organic and plastic mulching for potato production in the Czech Republic. The mulching with chopped grass (GM) and black textile mulch (BTM) were compared to non-mulching control variant (C) with mechanical cultivation. Especially in plots with BTM were first formed ridges and covered by the black polypropylene non-woven textile and then they were planting. During vegetation the infestation of Colorado potato beetle (CPB), weeds biomass, course of soil temperature and soil water potential were assessed. The results showed that surface of GM had a positive effect on soil temperature reduction, soil water potential depression. This study also indicated a positive effect of GM on the larvae of CPB diminution, on the other hand higher incidence of larvae and higher defoliation was observed in BTM. GM had a significant effect on the yield of potatoes. The yield of ware potatoes was higher by 27 % higher on plots with GM and by 16 % lower on plots wit BTM in comparison with C. NeemAzal T/S decreased statistically significantly % of defoliation and increased yield of ware potatoes by 35 % in comparison with control.

  • The analysis of ostrich chick vitality
    35-40
    Views:
    135

    Examinations on ostrich chick vitality can help to improve the effectiveness of Hungarian ostrich husbandry and hatching technology. The investigations were carried out on an ostrich breeder farm in Eastern Hungary. For the analyses, the Tona et al. (2003) scoring system was applied presenting eight main criteria (activity, feather, condition, eyesight, the condition of navel and leg, the amount of the remaining shell membrane and egg content, and the size and tenderness of the abdomen). Most chicks (98.08%) were vigilant and had clean and dry feathers. There was no difference between the average hatching weights between May and August but a decreasing tendency was shown during the laying season. The vitality total score was above 90 in each evaluated month and was not affected by the hatching month. Our results revealed that the vitality of chicks was not affected by either the hatching month (P=0.51) or the weight category (P=0.11). Neither the hatching weight of chicks and leg condition were correlated (P=0.79). Results showed that the Tona scoring system with small modifications can be well applied to ostrich chicks. Practical on-farm usage of the system can be suggested as an aid in day-old chick evaluation. After individual marking of chicks, the investigation of growth and culling rate could be carried out for more precise conclusions, involving more farms and laying seasons.

  • Congruency Analyses in Agricultural Organizations
    56-61
    Views:
    82

    Management is one of the ancient activities. Managerial behaviour helped humans to become sociable creatures. The aims and roles of management have continually changed along with social and economic changes. Some management theories in the early literature interpret the managerial function as „to instruct” and „to control” subordinates. The manager – having the appropriate authority – unilaterally appoints the expected activities in accordance with the objectives of the organization and his/her own wish. Its form is the instruction or the command.
    Later, organizations and management theories defined the managerial function rather as the impact on the employees than (or instead of) a unilateral manifestation of will. These focus on collaboration and imitation instead of on obedience. These theories were based on the fact that the employees work hard to succeed in meeting organizational goals because they want to meet their own needs, desires and wishes.
    Today, management means being in a relationship with colleagues, effective and successful working methods and, last but not least, commitment and liability for the company. The responsibilities of directors are to estimate the employees’ competences and to apply the workforce expediently.
    In our opinion, the two most important questions of human resource management (HRM) will be:
    • the expectations made of the manager by the subordinates,
    • the expectations made of the subordinates by the manager.
    The expectations of management have continuously evolved along with the social, political and economical improvement. We consider the most important requirements will be the following:
    • the exploitation of employees’ abilities (especially the leaders’),
    • the exploitation of human resource,
    • aim-oriented leadership related to different management levels.
    The actual research covers only the examination of managerial requirements. We experienced that the expectations are affected by many factors starting with the fulfillment of a specific task to the social environment as a whole. Managements of the last century did not require such self-reliance, creativity and broad knowledge from their subordinates as they do today. Employees have to be able to adapt to new tasks, technology and methods; have to react quickly against the problems; and be loyal to the company and the manager.
    We plan to expand our research backwards as well, in which we will search for the answer what kind of expectations are formulated by subordinates on the manager. Thus, we can approach and reveal the expectations (the examined factors) from two sides.
    Due to this method, we would like to work out such coherences which can help us to demonstrate the opinions of the differently qualified employees of the organisations. The applied method provides us facilities to carry it out in various organisational parameters, such as functional form, size, effectiveness, range of activity.

  • Soil biological challenges in our age
    193-196
    Views:
    155

    The paper deals with the soil biological research and its contribution to the changed cropping strategy and to the sustainable and environmentally friendly farming and management. The paper emphasizes the importance of biodiversity, as one of the most important ecological functions of soil. The organisms, populations and communities living in the soil play a key importance in the preservation of soil fertility. The most important research areas are presented dealing with in the last decades the national researchers and the challenges we face regarding the current soil biological problems. We have to prepare to examine the soil biological effectiveness of the more widely spread bio-preparations, bacterium preparations, and bioregulators. The prerequisites are the versatile knowledge of the biological state of soils and monitoring examination of the different effects soils had (including the mentioned preparations).

  • Environmental Consequences of Efficient Use of Nitrogen Fertilizers
    41-46
    Views:
    92

    Nitrogen fertilizer represents major economic burden. For this reason, although the efficiency of nitrogen utilization varies highly, its actual use generally remains at low levels; these averaging between 25 and 50%. We set up an experiment at the Oradea Research Station, using 15N labeled fertilizers, in order to investigate the possibility of increasing N fertilizer efficiency in winter wheat under irrigation conditions.
    Fertilizers labeled with 15N allows us to individually determine its effect on yield formation, as well as the use efficiency of N from fertilizer following application rate and time. The amount of N derived from fertilizer as determined in straw and grain yield is high. When the labeled fertilizer is applied at tillering time, the values of this indicator rise when higher N levels we applied.
    In separate experiments, we investigated a series of aspects connected to chemical fertilizer regarding the determination of the type of fertilizer, optimum time and rates of application; all these as a function of the special pedoclimatic conditions.
    The results obtained in the field show that the effectiveness of N utilization in wheat is most variable and generally low, often ranging between 25 and 33%, owing to N loss within the system through leaching and NH3 volatilization.
    A readily achievable increase in efficiency of 5 percentage points would result in considerable savings, and can be brought about by reducing nitrogen losses. The added benefits to the environment in terms of reduced ground/water contamination and lowered nitrous oxide (N20) emissions would also be substantial.
    The figures for N fertilizer use efficiency (% N range from 35.5 to 72.6, the highest value being recorded with an N application of 120 kg/ha at tillering, when the previous crop was sunflower).
    INTRODUCTION

  • A morphological survey of Ustilago trichophora, a smut fungi and evaluation as bioherbicidal agent for barnyard grass (Echinochloa crus-galli)
    91-93
    Views:
    169

    Ustilago trichophora (Link) Kunze is a widespread smut fungus in all over the world. This fungus is pathogenic on species of Echinochloa genus. The subject of present research was that smut fungi occurrence on barnyard grass (Echinochloa crus-galli). Numerous barnyard grass plants with symptoms of smut galls caused by Ustilago trichophora on stems were collected from two counties, víz. Hajdú-Bihar (East-Hungary) and Jász-Nagykun-Szolnok (Middle-Hungary). The infested plants were examined in laboratory, which included the observation of the symptoms and the morphological properties of the spores and the colonies developed from sporidia. The results suggested that this fungus could be effective against barnyard grass weed so the biological control of this weed plant (Echinochloa cruss-galli) can be managed by using Ustilago trichophora biopreparates. As Ustilago trichophora can produce abundant sporidia in liquid culture, a high effectiveness control should be apply by Ustilago trichophora smut fungus as a mycoherbicide in Echinochloa weed control.