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Vaistinis smidras (Asparagus officinalis L.) daugelyje šalių auginamas kaip delikatesinė daržovė. Tai vertinga ankstyvo pavasario periodo daržovė, kuri auga toje pačioje vietoje ir dera 12-15 metų ir ilgiau. Vaistinio smidro introdukuotų veislių tyrimai atlikti Lietuvos žemės ūkio universiteto sodininkystės ir daržininkystės katedroje 2009. Tirtos vaistinio smidro veislių ‘D’Argenteuil Primaticcio’, ‘Schwetzinger Meisterschub’, ‘Eposs’, ‘Schneekopf’, ‘Rambo’, ‘Gartner Saat’, ‘Ravel’, ‘Ramos’, ‘Ramada’, ‘Rally’, ‘Ranger’ savybės, o taip pat kontrolinė ‘Mary Washington’ veislė, nustatytas derėjimo ankstyvumas ir trukmė, derlingumas, įvertinti ūglių kokybės rodikliai. Nustatyta, kad augalų vegetacija prasideda ne vienu metu. 2009 m. vegetacija prasidėjo balandžio 16-21 d. Tyrimų metais smidrų derėjimo trukmė buvo 24-28 d. Didžiausias ūglių derlius gautas iš veislių ‘Schwetzinger Meisterschub’ ir ‘Ravel’, didžiausią sausųjų medžiagų kiekį sukaupė ‘Schneekopf’ veislės ūgliai, vitamino C – ‘Schwetzinger Meisterschub’. Mažiausiai nitratų sukaupė ‘Rally’. Ūglių kokybės rodikliai (ilgis, skersmuo, vidutinė masė) atitiko kokybės reikalavimo standartus. / Officinal asparagus (Asparagus officinalis L.) is a vegetable that is grown in many countries. It can be harvested each year in early spring for a period of 12 – 15 years or more. The Department of Horticulture at the Lithuanian University of Agriculture performed a study of introductory varieties of officinal asparagus in 2009. The study included the adopted varieties of officinal asparagus ‘D’Argenteuil Primaticcio’, ‘Schwetzinger Meisterschub’, ‘Eposs’, ‘Schneekopf’, ‘Rambo’, ‘Gartner Saat’, ‘Ravel‘‚ ‘Ramos‘, ‘Rally‘, ‘Ramada‘ ‘Ranger‘ and a control variety, ‘Mary Washington‘. The study analyzed the time and duration of harvest, fertility and sprout quality indicators for each variety. The study concluded that the vegetation for plants starts at different times. In 2009, the vegetation started on April 16-21. During the years when the study was performed, the duration of the harvest was very similar, for 24-28 days. In 2009 the biggest harvest of the sprout of asparagus was received from the ‘Schwetzinger Meisterschub’ and ‘Ravel’ varieties. In 2009 the sprout of ‘Schneekopf’ piled up the biggest amount of dry substance, ‘Schwetzinger Meisterschub’ had the biggest amount of vitamin C. Lower levels of nitrates were ‘Rally’. The indicators (length, diameter, average mass) of the sprout quality matched the standards of quality.

Doctor of Philosophy / Department of Agronomy / Guihua Bai / Allan K. Fritz / Wheat pre-harvest sprouting (PHS), germination of physiologically matured grains in a wheat spike before harvesting, can cause significant reduction in grain yield and end-use quality. Many quantitative trait loci (QTL) for PHS resistance have been reported in different sources. To determine the genetic architecture of PHS resistance and its relationship with grain color (GC) in US hard winter wheat, a genome-wide association study (GWAS) on both PHS resistance and GC was conducted using in a panel of 185 U.S. elite breeding lines and cultivars and 90K wheat SNP arrrays. PHS resistance was assessed by evaluating sprouting rates in wheat spikes harvested from both greenhouse and field experiments. Thirteen QTLs for PHS resistance were identified on 11 chromosomes in at least two experiments, and the effects of these QTLs varied among different environments. The common QTLs for PHS resistance and GC were identified on the long arms of the chromosome 3A and 3D, indicating pleiotropic effect of the two QTLs. Significant QTLs were also detected on chromosome arms 3AS and 4AL, which were not related to GC, suggesting that it is possible to improve PHS resistance in white wheat. To identify markers closely linked to the 4AL QTL, genotyping-by-sequencing (GBS) technology was used to analyze a population of recombinant inbred lines (RILs) developed from a cross between two parents, “Tutoumai A” and “Siyang 936”, contrasting in 4AL QTL. Several closely linked GBS SNP markers to the 4AL QTL were identified and some of them were coverted to KASP for marker-assisted breeding. To investigate effects of the two non-GC related QTLs on 3AS and 4AL, both QTLs were transferered from “Tutoumai A” and “AUS1408” into a susceptible US hard winter wheat breeding line, NW97S186, through marker-assisted backcrossing using the gene marker TaPHS1 for 3AS QTL and a tightly linked KASP marker we developed for 4AL QTL. The 3AS QTL (TaPHS1) significantly interacted with environments and genetic backgrounds, whereas 4AL QTL (TaMKK3-A) interacted with environments only. The two QTLs showed additive effects on PHS resistance, indicating pyramiding these two QTLs can increase PHS resistance. To improve breeding selection efficiency, genomic prediction using genome-wide markers and marker-based prediction (MBP) using selected trait-linked markers were conducted in the association panel. Among the four genomic prediction methods evaluated, the ridge regression best linear unbiased prediction (rrBLUP) provides the best prediction among the tested methods (rrBLUP, BayesB, BayesC and BayesC0). However, MBP using 11 significant SNPs identified in the association study provides a better prediction than genomic prediction. Therefore, for traits that are controlled by a few major QTLs, MBP may be more effective than genomic selection.

This diploma thesis deals with a relatively new branch of tourism - wine tourism. It is a gentle form of tourism which is being developed as a follow-up to the trend of sustainability. Wine tourism is discussed in the analysis of literature. In connection with foreign experience it is being studied whether this form of tourism is really as gentle as proclaimed. The practical part of the thesis is devoted to the wine tourism in the Czech Republic, with an emphasis on the wine region of Bohemia. Illustrated with examples of the towns of Mělník, Litoměřice and Most, the present state of this branch and its development potential are evaluated. The emphasis is on the products of the wine tourism which are suitable for these cities (wine harvest, wine-growing events and festivals, shows and competitions, etc.). Finally, the work mentions the increasing demand and need for coordinated management of the region (Destination Management).

Doctor of Philosophy / Department of Agronomy / P. V. Vara Prasad / Sweet sorghum (Sorghum bicolor L. Moench) is an important bioenergy crop. There is a wide array of genetic diversity in sweet sorghum germplasm collections. However, information on traits associated with sugar yield, optimum harvesting time for maximum sugar yield, effects of abiotic stresses on sugar yield is scarce. The objectives of the present study were: to identify traits that are associated with sugar yield, to determine the optimum harvesting time for maximum sugar yield and to understand the physiological responses of different sweet sorghum genotypes to drought and high temperature. In order to meet these objectives, five independent field and greenhouse studies were conducted. Field experiments were conducted using 280 sweet sorghum germplasm and were evaluated for 2 years. From this study, 30 genotypes representing high and low sugar yielders were selected for the subsequent experiment. We observed a significant variation in physiological, morphological and sugar yield traits associated with biofuel production. In the selection experiment, investigations on the morphological, physiological attributes helped to identify those characters which influence or limit sugar yield in the sweet sorghum. Another field study was conducted to optimize the harvesting time for obtaining highest sugar and juice yields in sweet sorghum. Sweet sorghum variety M81E was harvested at ten growth stages. Our results suggest that the optimum time for harvesting of sweet sorghum cultivar M81E is between milk and hard dough stages when highest sugar yield was observed. Studies on different levels of water stress were studied under greenhouse conditions. Four sweet sorghum genotypes (Awanlek, Smith, Tracy and Wray) were subjected to three water stress treatments (100% pot capacity (PC); 70% PC and 30% PC) for 20 days at early seed filling (Milk) stage. The results showed that genotypes differed significantly for all growth and yield, biochemical and physiological traits. Severe water stress significantly decreased juice and sugar yields by decreasing net photosynthetic rate, transpiration rate, stomatal conductance and sucrose content in the stem juice. Genotypes Tracy and Wray produced significantly highest brix, stem fresh weight, juice and sugar yield under both irrigated and water stress conditions. In another greenhouse study, we quantified the effects of drought, high temperature, and their combinations on growth, physiology and yield of sweet sorghum genotypes. The same four genotypes above were subjected to four treatments, T1 - control, T2 - drought stress, T3 - high temperature stress and T4 - combination of drought and high temperature for 16 days after anthesis. The result showed that significant difference was observed for growth and yield traits, physiological traits and non-reducing and total sugar content in juice for genotypes and treatments. Among the genotypes Tracy recorded higher juice and sugar yield. Among the various treatments, combination of drought and high temperature was found to be more deleterious in reducing most of the biofuel traits followed by drought and high temperature stress. The above studies gave significant findings with regards to the identification of superior sweet sorghum germplasm, their tolerance capacity to different abiotic stresses, which allows better selection for the use of bioenergy production.

Doctor of Philosophy / Department of Diagnostic Medicine/Pathobiology / T. G. Nagaraja / Escherichia coli O157:H7 and over 380 non-O157 serotypes of Shiga toxin producing E. coli (STEC) are human food-borne pathogens that inhabit the hindgut of ruminants and are shed in the feces, which subsequently contaminate food products. Recent epidemiological data have shown that six non-O157 STEC (O26, O103, O111, O121, O45 and O145) account for majority of human STEC infections. Fecal shedding of STEC is influenced by a number of factors, including diets, supplements, and feed additives, because of their potential to alter hindgut ecosystem. Not much is known about the fecal shedding of non-O157 STEC in cattle because of lack of standardized detection methods. Fecal shedding of E. coli O157:H7 was studied to determine the effects of supplemental urea, monensin, an ionophore, and ractopamine, a beta-agonist. Cattle fed monensin at 44 mg/kg of feed had lower (P = 0.05) fecal O157:H7 prevalence than cattle fed 33 mg/kg. Supplemental urea (0.35 or 0.70% of the diet) and inclusion of ractopamine at 200 mg/animal/day had no effect on fecal shedding of E. coli O157:H7. In an experimental inoculation study, inclusion of corn starch to a distiller’s grains (DG)-supplemented diet had no effect on fecal shedding of E. coli O157 suggesting that either the decreased starch content in the DG-supplemented diet is not a factor in the increased shedding of E. coli O157:H7 or inclusion of pure starch in the diet may not have achieved our intended goal to have starch flow into the hindgut similar to that of corn grain. A multiplex PCR to detect O26, O45, O103, O111, O121, O145, and O157 was designed and applicability to detect the seven serogroups in cattle feces was evaluated. A multiplex PCR, designed to detect E. coli O104, feces showed presence of O104 in cattle feces (20.6%), but the isolated strains did not carry genes characteristic of the virulent strain responsible for the 2011 food-borne outbreak in Germany. Two preharvest interventions, a siderophore receptor and porin proteins-based vaccine and a Lactobacillus acidophilus-based direct-fed microbial, intended to control E. coli O157, had no effect on fecal shedding of O26 assessed by culture-based or PCR-based method.

Different techniques are being implemented in modern communication networks to ensure that their coverage, capacity, and other user-experience requirements are always met. In this thesis, I consider multi-antenna techniques, energy harvesting, and the dense deployment of small cell base stations in a two-tiered wireless powered communication network (WPCN) where multi-antenna transmitters utilize a Harvest Then Transmit (HTT) protocol to coordinate wireless energy harvesting and information transmission with their associated users. To satisfy network throughput requirements at all user positions, I formulate multi-constraint optimization problems to maximize the minimum data rate at both tier and network levels, solving the resulting non-convex expressions with an algorithm which incorporates the Perron-Frobenius non-negative matrix theory for alternate parameter optimization. I also present a less complex solution methodology, compared the performance of both and provided interesting insights on my findings. / October 2016

Tomatoes are widely produced and consumed due to their nutritional content and versatility. However, the tomato is a soft fruit liable to damage and flavour deterioration. Hence, the main challenge for the tomato producing industry is to prevent the high loss incurred during harvest, handling and transportation of the crops. The objective of this study was to investigate the overall nutritional implication of controlled storage of tomatoes using ozone on the ripening process and the basic nutritional components of tomatoes. This investigation was also designed to focus on the effect of different ozone doses on the basic components and properties (carotenoids, ascorbic acid, total antioxidant activity and soluble sugars content) of the quality and dynamic maturity of tomatoes. Green tomatoes (Rio Grande) were treated in glass chambers with ozone enriched air [(air + 2, 7 and 21 mg O3/g tomato) and control (air only)] under humidity and temperature of 90-95% and 14-17 oC respectively. Tomatoes were sampled after 14 days of ozone treatment in the storage chamber and analyzed for different quality parameters (appearance, weight loss, Total Soluble Solids (TSS), titratable acidity, total ascorbic acid and carotene) of the ripening. The variety Elegance tomatoes were selected and the fruits were graded by colour and subjected to treatment with ozone (in doses 0 (clean air), 0.25, 0.50, and1.00 mg O3/g tomatoes) during storage for 6 days under the same humidity and temperature conditions. The fruits were analysed for carotenoids, ascorbic acid content, total antioxidant activity and soluble sugars. Analysis of the fruits clearly showed that ozone significantly delayed the development of colour on the surface, particularly in the low doses, and caused black spots on the surface of the tomatoes, particularly in higher ozone doses. Ozone did not affect the ascorbic acid and titratable acidity content. However ozone did reduce the Total Soluble Solids (TSS) by about 10% at the lowest ozone dose. A high inhibition of accumulation of carotenoids, particularly at low dose, of the tomatoes (Rio Grande) was also observed. Tomatoes (Elegance) under ozone treatments contained higher ß-carotene than those under the control treatment and lycopene content increased during storage in the red stage of tomato fruits. Ascorbic acid (AsA), dehydroascorbic acid (DHA) and the total of AsA and DHA concentrations, and ratios of redox (ASA/ (ASA + DHA) and DHA/AsA in pericarp and pulp of tomatoes tissue, did not show clear differences between the different treatments. The concentrations of the glucose and fructose increased in the tomatoes which were subjected to ozone treatments. Results from this study show that controlled atmosphere storage of tomatoes using ozone is a viable technique which warrants further study.