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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Πειραματική καλλιέργεια ηλίανθου σε υπόστρωμα τέφρας με στόχο την εκτίμηση περιβαλλοντικών συνθηκών

Αναστασίου, Δημήτριος 02 February 2011 (has links)
Πραγματοποιήθηκε πείραμα με στόχο τη μελέτη των περιβαλλοντικών συνθηκών πειραματικής καλλιέργειας ηλίανθου σε υπόστρωμα τέφρας. Για την μελέτη του θέματος εγκαταστάθηκε πειραματικός αγρός στην παραλιακή περιοχή του χωριού Μηλάκι του δήμου Ταμυνέων (Αλιβερίου) στο νομό Ευβοίας. Η σπορά του ηλίανθου έγινε με την φύτευση σπόρου με το χέρι στις 27 Απριλίου του 2009 σε δυο διαφορετικά υποστρώματα, της ήδη υπάρχουσας στην περιοχή, τέφρας και σε κανονικό εδαφικό υπόστρωμα το οποίο μεταφέρθηκε στην περιοχή. Για τις ανάγκες του πειράματος χρησιμοποιήθηκαν και στα δυο υποστρώματα τα πιο κάτω εδαφοβελτιωτικά (γύψος, τύρφη, περλίτης, πριονίδι) καθώς και αναμείξεις αυτών. Η μέγιστη τιμή του ολικού ύψους των φυτών στο υπόστρωμα της τέφρας, παρατηρείται στις 18 Ιουλίου του 2009, ενώ για την παράμετρο της διαμέτρου των ανθοκεφαλών η μέγιστη τιμή της παρατηρείται στις 2 Αυγούστου του 2009. Τα ίδια συμπεράσματα προκύπτουν και από τα δεδομένα που ελήφθησαν από το κανονικό εδαφικό υπόστρωμα. Υπολογίστηκαν οι συντελεστές συσχέτισης των φυτικών παραμέτρων στα διάφορα πειραματικά πεδία. Αυτές έδειξαν ότι οι θετικές αλλά και οι αρνητικές συσχετίσεις μεταξύ των ίδιων συγκρινόμενων παραμέτρων (Μεσοδιάστημα Κοτύλη – 1ο φύλλο, Μεσοδιάστημα 1ο φύλλο – 2ο φύλλο, Ολικό ύψος, Φυλλική επιφάνεια 1ου φύλλου, Φυλλική επιφάνεια 2ου φύλλου, Διάμετρος ανθοκεφαλής, Βάρος φυτού), είναι μεγαλύτερες στο υπόστρωμα της τέφρας από αυτό του κανονικού εδαφικού υποστρώματος. Εξαίρεση αποτελούν δυο περιπτώσεις, όπου στο υπόστρωμα της τέφρας εμφανίζεται αρνητική συσχέτιση ενώ στο κανονικό εδαφικό υπόστρωμα εμφανίζεται θετική συσχέτιση. Διαπιστώθηκε ότι στο υπόστρωμα της τέφρας, οι μεγαλύτερες τιμές των παραμέτρων που μετρήθηκαν κατά τη διάρκεια του πειράματος παρατηρήθηκαν στα πειραματικά τετράγωνα με τα παρακάτω εδαφοβελτιωτικά: T5A, G.T4A, G.T5A, G.T.PL3A και G.T.PL4A. Στο κανονικό εδαφικό υπόστρωμα, διαπιστώθηκε ότι οι μεγαλύτερες τιμές των παραμέτρων που μετρήθηκαν κατά τη διάρκεια του πειράματος παρατηρήθηκαν στα πειραματικά τετράγωνα με τα παρακάτω εδαφοβελτιωτικά: G.T5B, G.T.PL4B, G.T.PL5B, G.T.PL.PN4B και G.T.PL.PN5B. / An experiment was realised amining at the study of environmental conditions experimental growing of sunflower in sublayer of ash. For the study of this subject was installed experimental field in the coastal region of the village Milaki at the municipality Tamyneon (Aliveriou) in the prefecture of Evia. The seeding of sunflower became with the planting of seed by hands on 27 April 2009 in two different sublayers, the already existing in the region, ash and in regular territorial sublayer which was transported in the region. For the needs of experiment they were also used in the two sublayers the below ameliorative of ground (gypsum, peat, perlite, sawdust) as well as mixtures of these. The biggest price of the total height of plants in the sublayer of ash, is observed on 18 July 2009, while for the parameter of heads diameter her biggest price is observed on 2 August 2009. The same conclusions also result from the data that were received from the regular territorial sublayer. They were calculated the correlation factors of the plant parameters in the various experimental fields. These showed that positive but also negative correlations between the same compared parameters (Cotyledon – first leaf interval, First leaf – second leaf interval, Total height, Leaf surface of first leaf, Leaf surface of second leaf, Head diameter, Weight of plant) are bigger in the sublayer of the ash from that of the regular territorial sublayer. Exception constitutes two cases, where in the sublayer of ash is presented negative correlation while in the regular territorial sublayer is presented positive correlation. It was realised that in the sublayer of ash, the biggest prices of the parameters that were measured at the duration of experiment were observed in the experimental squares with the following ameliorative of ground: T5A, G.T4A, G.T5A, G.T.PL3A και G.T.PL4A. In the regular territorial sublayer, was realised that the biggest prices of the parameters that were measured at the duration of experiment were observed in the experimental squares with the following ameliorative of ground: G.T5B, G.T.PL4B, G.T.PL5B, G.T.PL.PN4B και G.T.PL.PN5B.
52

Πειραματική καλλιέργεια φυτών με στόχο εφαρμογές για την προστασία του περιβάλλοντος

Δανιηλίδου, Ελένη 21 October 2011 (has links)
Οι σύγχρονοι ρυθμοί ανάπτυξης και εξέλιξης του ανθρώπου και της κοινωνίας του διαταράσσουν τις δυναμικές ισορροπίες που επικρατούν στο περιβάλλον, με αποτέλεσμα την αποσταθεροποίηση των εδαφών και κατ’ επέκταση τη διάβρωση και ερημοποίηση τους. Αυτή η διαταραχή μπορεί να μετατρέψει ένα απαραίτητο θρεπτικό ανόργανο σε ρυπαντή λόγο την υπερβολικά μεγάλης διαθεσιμότητας του. Στην προσπάθεια του ο άνθρωπος να επαναφέρει το περιβάλλον την πρότερη κατάσταση του έχει εφαρμόσει διάφορες φυσικές και τεχνικές μεθόδους απομάκρυνσης των ρύπων και σταθεροποίησης των εδαφών. Σε αυτή την μεταπτυχιακή διατριβή μελετήθηκε μια πειραματική καλλιέργεια ηλίανθου, Helianthus annnus και H. giant, με στόχο να εξαχθούν χρήσιμα συμπεράσματα για την προστασία του περιβάλλοντος. Χρησιμοποιήθηκαν υποβαθμισμένα εδάφη διαφορετικής σύστασης (φρύγματα σιδηροπυρίτη, μηλαϊκή γη και γύψος σε διάφορες αναλογίες) και μελετήθηκε ο βαθμός ανάπτυξης των ηλίανθων σε σχέση με αυτά τα υποστρώματα. Τα αποτελέσματα των μετρήσεων έδειξαν ότι ο βαθμός ανάπτυξης των φυτών ανάλογα με την ποιότητα του υποστρώματος είναι ικανοποιητικός ανεξάρτητα από την σύσταση του, επιτρέποντας τα φυτά να ολοκληρώσουν τον βιολογικό τους κύκλο χωρίς να παρουσιάζονται συμπτώματα χλώρωσης. Αξίζει να σημειωθεί ότι τα υποστρώματα με προσθήκη γύψου έδωσαν κοντύτερα φυτά σε σχέση με αυτά που είχαν μηλαϊκή γη που έδωσαν τα πιο ψηλά φυτά. / Man and his modern rythms of growth and development disturb the dynamic balances that prevail in the environment, as a result the destabilisation, the erosion and the desertation of the soil. This disturbance can change an essential nutritious element to a polluter because of the excessively big availability. In the effort to restore the environment at previous situation man has applied various natural and technical methods to remove of pollutants and stabilize the soil. In this postgraduate thesis was studied a experimental culture of sunflower, Helianthus annnus and H. giant, in order to exported useful conclusions on the protection of environment. It was used downgraded soil of different constitution (burned pyrite, coarse ground and plaster in various proportions) and was studied the degree of growth of sunflowers. The results of measurements showed that the degree of growth of plants depending on the quality of sublayer, was satisfactory independent from its constitution, allowing the plants to complete their biological circle without symptoms of chlorination. It has to be mentioned that sublayers with addition of plaster gave shorter plants compared to coarse ground which gave the tallest plants.
53

Biology and epidemiology of Plasmopara halstedii on sunflower.

Goossen, Philippus G. January 1965 (has links)
No description available.
54

Mechanisms of pathogenesis in Sclerotium bataticola on sunflowers.

Chan, James Yu-Ho. January 1968 (has links)
No description available.
55

Reticulate evolution in Helianthus (Asteraceae)

Timme, Ruth Evangeline 28 August 2008 (has links)
Not available / text
56

Studies of integrated control of selected root diseases of sunflowers using Trichoderma harzianum (ECO-T®) and silicon

Elungi, Konis. January 2009 (has links)
The soil-borne fungi Rhizoctonia solani Kuhn and Sclerotinia sclerotiorum De Bary are ubiquitous plant pathogens with a wide host range. They are among the most widespread and destructive diseases of many crops, including sunflowers. Although in many cases, the use of chemicals appears to be the most economical and efficient means of controlling plant pathogens, their environmental concerns and the development of tolerance in pathogen populations have led to drastic reduction in their usage and increased the need to find alternative means of disease control. The potential benefits of applying Trichoderma harzianum Rifai and silicon (Si) nutrition to plants have been extensively reviewed. In this study, the ability of T. harzianum (Eco-T®), soluble silicon, and their combination was evaluated on sunflower (Helianthus annuus L.), for their potential to suppress pathogenic strains of R. solani and S. sclerotiorum. The ability of this crop to take up and accumulate Si in different plant parts was also investigated. In vitro assessment of fungal responses to Si in PDA showed that both R. solani and S. sclerotiorum were inhibited in the presence of Si. More inhibition was observed as the Si concentration increased with a relative increase in pH. Maximum growth inhibition was observed at 3000 mg ;-1 – 6000 mg ;-1 of PDA. No difference in inhibition between the two pathogens was observed, thus confirming the fungitoxic/suppressive ability of high Si concentrations to fungal growth. In addition, in vivo trials showed that the Si concentration of 200 mg ;-1 applied weekly significantly increased the dry weight of plants inoculated with R. solani and S. sclerotiorum and was therefore considered the optimum concentration. Assessments on in vitro antifungal activities of Eco-T® on R. solani and S. sclerotiorum, showed that Eco-T® significantly inhibited mycelial growth, in both dual culture methods and volatile and non-volatile compounds produced by Eco-T®. In addition, the combination of Eco-T® and Si was most effective in suppressing damping-off and increasing plant dry weight of sunflower seedlings in the greenhouse. The combination of Si and Eco-T® significantly increased percentage germination, number of leaves and head dry weight of the sunflower cultivars tested. Silicon alone increased growth but was unable to control R. solani and S. sclerotiorum effectively. Rhizotron studies showed that S. sclerotiorum infected the host through the roots and the stem, whereas R. solani only infected the host through the roots. A study on Si uptake and distribution showed that sunflower accumulates Si in various plant tissues. Analysis of plant tissues revealed that more Si was accumulated in leaves > stems > roots, with the Si levels in leaves being significantly higher than in stems and roots. In conclusion, Si alone could be used to increase growth but was unable to control R. solani and S. sclerotiorum. However, Si together with Eco-T® provides an environmentally friendly alternative for the control of R. solani and S. sclerotiorum, and enhanced plant growth and yield. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.
57

Genetic diversity of proprietary inbred lines of sunflower, determined by mapped SSR markers and total protein analysis.

Erasmus, Tertia Elizabeth. January 2008 (has links)
This study compared DNA based SSR markers with total seed protein markers, used to evaluate genetic diversity of sunflower. The multiplex-ability, cost effectiveness and applicability of microsatellites as molecular markers for a genetic diversity study were investigated and evaluated based on pedigree data of the sunflower germplasm. A solution for oil and fat interference in ultrathin iso-electric focusing gels was investigated, in order to make imaging and interpretation easier and clearer. Total protein analysis was utilized for the determination of genetic diversity on the same inbred material used for the DNA analysis. Finally a correlation is made between the data obtained on DNA vs Protein compared with phenotype and expected pedigree data. A set of 73 SSR markers with known mapped positions were utilized to determine genetic similarity in a group of sunflower inbred lines. Cluster analysis of genetic similarity revealed an excellent correlation with the breeding background and source information obtained from breeders on all inbred lines used in this study. Cluster analysis gave a clear differentiation between B and R-lines, showing clearly defined heterotic groups of the proprietary set of inbred lines. The most outstanding single-locus SSR markers in the set used for this study were identified and used as a core set. Multiplex assays were designed and optimized for the most cost and time effective method for rapid variety identification. The selected markers produced robust PCR products, amplified a single locus each, were polymorphic among the elite inbred lines and supplied a good, genome-wide framework of completely co-dominant, single-locus DNA markers for molecular breeding. The use of a fluorescent-tailed primer technique resulted in a considerable cost saving. Furthermore, the SSR markers can be multiplexed through optimization, in order to avoid undesirable primer-primer interactions and non-specific amplification. First stage iso-electric focusing of total protein extracts were used to analyze sunflower looking at genetic purity and genetic variety verification on diverse sunflower germplasm. Severe visual interference was visible on most seed storage protein extracts of sunflower. This interference was visible as a distortion in the gel matrix on the anodal end of the gel, and caused important proteins to denature in the presence of heightened field strength and the absence of a uniform matrix. Adjustment of the extraction solutions removed this interference. Total protein profiles were generated with the use ultrathin layer iso-electric focusing (UTLIEF) to assess the level of genetic diversity on the same set of sunflower lines used for the SSR analysis. Finally, the genetic diversity of the sunflower germplasm was analysed by comparing proteomic, genomic and pedigree data from the same germplasm. A total of 295 alleles were amplified with a set of 73 SSR markers with known mapped positions. These were utilized to determine the genetic relatedness of a group of B-lines and R-lines of sunflower. In parallel, a total of 68 protein bands were visualized using protein samples of two types of seed storage proteins derived from exactly the same sunflower lines. Cluster analysis clearly differentiated between the B-lines and R-lines, identifying defined heterotic groups of this proprietary set of lines. The comparison of DNA and protein data for the application of genetic diversity studies is analysed, as well as the general comparison on the use of the two different molecules as markers. / Thesis (Ph.D)-University of KwaZulu-Natal, Pietermaritzburg, 2008.
58

Selecting donor inbred lines for enhancing the performance of single-cross hybrids from key heterotic groups of oilseed sunflower (Helianthus annuus L.)

Cheres, Mercy Tuiya 28 May 1998 (has links)
Graduation date: 1999
59

Effects of feeding raw and roasted sunflower seeds on ruminal fermentation, nutrient utilization and milk production of dairy cows

Sarrazin, Pascale. January 2003 (has links)
Three studies were conducted to determine the effects of roasting on ruminal degradability of sunflower seeds and the effects of feeding roasted sunflower seeds on ruminal fermentation, nutrient digestibility and milk yield and composition of dairy cows. Experimental treatments were a control diet with no added sunflower seed, a raw sunflower seed diet and a roasted sunflower seed diet. Sunflower seed diets contained 6% fat whereas the control diet contained 3% fat. In study one, two ruminally fistulated cows were used in a randomized complete block design to determine the effects of roasting on ruminal degradation of sunflower seeds. In the second study, three ruminally cannulated lactating Holstein cows were used in a 3 x 3 Latin square experiment to determine the effects of dietary treatments on ruminal fermentation and total tract nutrient utilization. In the last study, three primiparous and six multiparous Holstein cows were used in three 3 x 3 Latin squares to determine the effects of dietary treatments on milk yield and composition.
60

Cross protection in sunflower against Verticillium dahliae and Plasmopara halstedii

Price, Doris M. January 1984 (has links)
No description available.

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