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Výskyt patogenů v porostu lilku bramboru
Novák, Ondřej
This bachelor thesis is focused on the occurrence of pathogens in the potato (Solanum tuberosum L.) crop. The objectives of the thesis were to describe potato, to describe the pathogens that attack potato and, in the practical part, to observe and evaluate the occurrence of late blight, early blight (on chemically treated and untreated parts of the plot) and Y – virus of potato. In each section, pathogen incidence was monitored on 15 varieties. Late blight occurred only minimally in the crop. This was due to the dry and warm weather during the growing season, which caused minimal spread of the disease. On the other hand, early blight occurred on all varieties surveyed. This disease usually appears in the crops during the warm and intermittently wet season. Y-virus of potato was significantly present on one third of the varieties surveyed. The occurrence was caused by a record infestation of the peach aphid, which transmits the PVY virus.
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Účinnost vybraných silic při ochraně bramboru vůči bakterii Pectobacterium atrosepticum
Mokrá, Kristýna
The aim of the thesis was to evaluate the effect of the active substances of essential oils (thyme, oregano, rosemary, natural thymol, synthetic thymol, carvacrol, menthon, cinnamon) against the Gram-negative bacterium Pectobacterium atrosepticum. The efficacy of essential oils was determined under laboratory conditions using the disk diffusion method, the values of minimum inhibitory concentration and minimum bactericidal concentration. Also, a pathogenicity test was performed on potato tubers with selected essential oils (thyme, thymol natural, and cinnamon). The components natural thymol, synthetic thymol, and the essential oil of cinnamon showed the best results, while menthone and carvacrol showed poor effects against the tested bacteria.
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Determination of nutritional values and antioxidant capacity of different edible roots
Ciffrová, Karolína ; Bendová, Agáta (referee) ; Němcová, Andrea (advisor)
This bachelor thesis deals with selected edible roots, their nutritional composition, antioxidant capacity and use in healthy eating. Eight selected edible roots were analyzed: type A, B and C potatoes, red potatoes, sweet potatoes, and purple potatoes were selected as representatives of potatoes. Jerusalem artichoke and cassava represent the other two root crops. The theoretical section of the thesis describes the basic characteristics of root crops, as well as the description and composition of the nutritional substances they contain, i.e. proteins, carbohydrates, fats, vitamins and antioxidant properties. The general characteristics of the methods used for analysis are also described here. The experimental part is based on specific analyses, procedures, results, chemicals and laboratory equipment used to determine the basic nutritional values and antioxidant capacity of these selected root vegetables. First, the total dry matter content was established to be about 23 % in the selected root crops. Higher dry matter content was determined for the cassava at 35 %. Crude protein content determined by the Kjeldahl method ranges from 6.5-9.9 %. The gravimetrically determined fiber in the given root crops was in the range of 0.27–0.91 %. The starch content is significantly higher in the cassava (46 %) than in other root crops. The inulin content was determined in sweet potatoes and Jerusalem artichokes instead of starch content; this value is significant for the Jerusalem artichoke (258.58 g/kg). Fat content in grams per 100 grams of dry matter was determined by Soxhlet extraction. Significant fat content was determined for sweet potatoes (12.6 g/100 g). From the extracted fats, the fatty acid profile was determined for individual root vegetables, such as the content of saturated (SFA), monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA). Total and reducing carbohydrates, determined by the spectrophotometric method, were measured separately in the peel and pulp of the root crops. Antioxidant capacity was determined using antioxidant activity values, polyphenol and flavonoid concentrations. Of the vitamins, vitamin C was determined, vitamin E only in type B, C and purple potatoes. For sweet potatoes, beta-carotene was determined to be 540.56 g/g. The measured and calculated results are plotted in graphs. Finally, there is a discussion of the conclusions of the individual methods.
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Biology and control of weeds in root crops (Solanum tuberosum Wild.)
SAMOHEJL, Petr
In the theoretical part, agricultural techniques in the cultivation of potatoes were described and selected weed species were characterized, those that cause damage not only regarding root crops. Chemical protection is currently considered to be an important and most represented method for the regulation of weed species. It resides in the use of plant protecting herbicide products to limit the population of weed species below the economic hazard threshold. The practical part of the bachelor's thesis is focused on monitoring the biology and regulation of weeds in the cultivation of root crops (Solanum tuberosum Wild.). On an experimental plot of land managed by the Samohejl family near the village of Malešice (district České Budějovice) in the South Bohemian Region. Three potato varieties (Adéla, Belana, Marabel) and three different herbicides (Arcade 880 WG, Mistral and Sencor Liquid) were compared and the yield of tubers of cultivated potato varieties was monitored at the same time. The results showed that the effect was different for each herbicide. Due to their active substance (metribuzin), the small effect of these products was manifested on sow thistle and creeping spider. As a secondary result, the yield of tubers of individual varieties of potatoes in different treatments was monitored, when individual varieties responded to different herbicide treatments and thus provided different yields in these cases.
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Využití entomopatogenních hub proti škůdcům
Skalníková, Leona
The bachelor thesis aims for verifying the efficiency of Naturalis agent against wi-reworms in growths of potatoes. Naturalis is a biological insecticide based on germinating spores of entomopathogenic fungi Beauveria bassiana (Bals.-Criv.) Vuill., (1912). The experiment was established on sites in Pasohlávky, Řepníky and Nyklovice from the 17th April to the 14th August 2018. Two variations were esta-blished for each site, one treated with Naturalis, one without treatment. Occurence of wireworms was assessed in food traps before and after the treatment. During the season, the assessment was realized up to three times. Wireworms were found on the site in Nyklovice only. 25 of individuals were found on the treated variation while 32 were found on non-treated variation. Presence of Beauveria bassiana was not noticed on any wireworm found. In 2018, the efficiency of Naturalis was not verified.
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Cryopreservation of sensitive potato genotypes
Faltus, Miloš ; Bilavčík, Alois ; Zámečník, Jiří
This methodology describes the preparation of explants prior to cryopreservation, dehydration of shoot tips, procedure and principles of sample cryopreservation, regeneration of control plants, including evaluation of explant survival and regeneration for sensitive potato genotypes which were formerly very difficult to cryopreserve. Ministry of agriculture of the Czech Republic is the user of this methodology and it applies it in the framework of the "National program for conservation and utilization of plant genetic resources, animals and micro-organisms important for nutrition and agriculture".
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Hereditary and non-hereditary factors affecting starch content in potato tubers
Malá, Lucie ; Sedláková, Vladimíra (advisor) ; Dvořák, Petr (referee)
This literature review relates to the starch which is presented in potato tubers, and hereditary and non-hereditary factors that influence content of the starch. At the beginning of the work, the attention is paid to the potatoes itself, especially their general characteristics. It should also mention the content of substances in tubers and their impact on human health. Further, the work is focused on the main thema, especialy starch present in potato tubers. Starch has considerable importance for the entire national economy, currently used not only in the starch industry, but it is more frequently used in other industries, for example paper or textile industry. Starch is composed from two important polysaccharides, amylose and amylopectin which are described in details. There are factors, that may influence starch content in potato tubers, like genetic and environmental factors. The simplest genetic factor that can influence the content of starch in potato tubers is crossing. The biosynthesis of starch is very important, which depends on several enzymes that initiate the metabolic pathway. It is pyrophosphorylase, starch synthase (SS), enzymes branched starch (SBEs) and enzymes unbranched starch (DBES). Starch synthase plays an important role here, in particular her isoform GBSS (granule bound starch synthase), which synthesizes amylose. Amylopectin is synthesized by a complex of enzymes SSI, SSII, SSIII, SSIV. The manipulation of single sugar genes metabolism can affect the formation and composition of starch in any variety of potatoes. This manipulation is called transgenesis and her goal is the creation of new potato genotypes. We can produce potato starch with high amylose by inhibiting enzymes SBE A and SBE B. A starch with a high amount of amylose is highy asked from the industry, because starch has unique functional properties. It should be mentioned DNA markers that has connection with the cultivation of potatoes and offers new opportunities for selecting potatoes genotypes. With DNA markers is linked MAS analysis and the associated method PCR polymerase chain reaction method. Another important method is QTL method. The environmental factors which influence the starch content of potatoes, which are mentioned in this work, are drought, light, cold. It should also be noted that even postharvest stress has a negative effect on starch content in potato tubers. Environmental stress affects and changes the yield of the starch.
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Acrylamide in potato products
Jiruška, Jan ; Sedláková, Vladimíra (advisor) ; Dvořák, Petr (referee)
This thesis provides a review describing acrylamide (AA), its detection and reduction. Botanical description and list of registered varieties of Solanum tuberosum in the Czech Republic is provided. Attention is payed to chemical composition of tubers. Next step is about AA. AA can cause carcinogenic and neurotoxic effects, particularly because it can be converted to a more reactive compound glycidamide in a human body. Thanks to animal experiments, we can reveal negative effects on the human body.
AA is formed by heat treatment over 120 °C in potatoes. Therefore, it is in potato chips and crisps. It is reaction of the free amino acids (especially asparagine) and reducing sugars (mostly glucose or fructose). It is all about several consecutive reactions that are included in the Maillard reaction. This reaction causes typical taste and aroma in products. Unfortunately, AA is one of the byproducts.
Today, formation of acrylamide has growing attention, because scientists want to reduce it as much as possible. Growing, industrial processing of potatoes and addition of additives during heat treatment is included. Antioxidants can significantly prevent formation of AA in food. There are also gathered informations on advanced analytical methods to detect AA in food. Rapid methods of detection are becoming more popular by scientits, that is why they are also included.
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Androgenesis and its using for interspecific hybridisation of potato
Suková, Eva ; Sedlák, Petr (advisor) ; Matiska, Pavel (referee)
The production of homozygous lines has been an important part of breeding programs. The most effective and widely used method suitable for the production of homozygous plants is induced androgenesis via anther, pollen and isolated microspore cultures. The principle of androgenic induction consists in reprogramming microspores from gametophytic to sporophytic development. Physical or chemical factors can be used on the whole inflorescence, flower-buds or isolated anthers for reprograming. The genotype of donor plant and poolen developmental stage plays a fundamental role in determination of androgenesis in vitro. Pre-treatments such as chilling, high temperature, high humidity, centrifugation, water stress, oxidative stress, osmotic pressure change in the level of endogenous growth substances, transfer anthers from anaerobic to aerobic environment, starvation, colchicine application and, heavy metals treatment are other important factors that affect the response of anthers to in vitro culture.
The aim of this work was to design and confirm the methodology used for induced androgenesis of potatoes. The achieved results of our experiment showing only trends and hypotheses. The size of the most suitable flower-buds for anther culture is 2-3 mm. It is highly likely that the sucrose concentration in MS medium had no impact on the callus induction. The genotype of tested hybrids probably plays a major role in the induced androgenesis process. The influence of the media on the formation of callus was statistically proven. Calluses were transferred to regeneration medium, but organogenesis has not yet come through.
The results show that the proposed methodology is appropriate to derive calluses at least.
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Výskyt patogenů v porostu bramboru
Petržela, David
This bachelor thesis is about the occurrence of pathogenes in the crop potatoes (Solanum tuberosum). The aim of thesis is observing the occurrence of Phytophtora infestans, kingdom Chromista. The observing was in Pustiměř, region Vyškov, in the year 2014. The presence of pathogens in the crop potatoes is evaluated according to the amount of rain and the temperature. The pathogen was found four times in this location during three months. The specific symptoms of Phytophtora infestans were observed approximately every seventh day after the rain. The other pathogens in the growth of potatoes had virus, bacterial or fungi characters.
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