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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.
11

Beiträge zur vergleichenden Anatomie von Zwiebel- u. Knollenschalen

Horst, Hellmuth. January 1909 (has links)
Thesis (doctoral)--Universität Zürich, 1909. / Cover title. Includes bibliographical references.
12

Scutellonema bradys as a pathogen of yam in Benin

Baimey, Hugues Kossi. January 2006 (has links)
Thesis (Ph.D.)(Microbiology and Plant Pathology)--University of Pretoria, 2006. / Includes summary. Includes bibliographical references. Available on the Internet via the World Wide Web.
13

Yield and quality of potatoes as affected by calcium nutrition, temperature and humidity

Modisane, Pulane Charity. January 2007 (has links)
Thesis (M.Sc.(Agric.))(Agronomy)--University of Pretoria, 2007. / Includes summary. Includes bibliographic references. Available on the Internet via the World Wide Web.
14

Influence of priming potato ( solanum tuberosum) seeds in solutions of three phytonematicides on potato growth and nematodes

Thopola, Tshegofatso Eva January 2020 (has links)
Thesis (M. A. Agricultural Management (Plant Production)) -- University of Limpopo, 2020 / Although potato seed priming in water is not allowed for quality-related reasons in tubers of the produced crop, it was viewed as necessary to use the technique as a carrier of active ingredients of phytonematicides, with the hope that should the technique work, then other solutions could be used for priming of potato tuber seeds. The objectives of this study were to investigate the feasibility of using potato seed tubers as carriers of cucurbitacin A, cucurbitacin B and momordin from triterpenoid- containing phytonematicides to improve management of nematode population densities in potato plants under greenhouse, microplot and field conditions, respectively. In single treatments (A1B0M0, A0B1M0 and A0M0B1), potato seed tubers were without any phytotoxicity in 3% solutions, in any two permutations (A1B1M0, A1B0M1 and A0M1B1) at 1.5% each and at three permutations (A1B1M1) at 1% each, for 7 h and then dried under shade for 2 h prior to planting. Twenty-cm-diameter plastic pots were filled with 2 700 ml growing medium under greenhouse conditions and placed on benches at 0.3 m × 0.2 m spacing. Under microplot 30-cm-diameter plastic pots were used and pots were then inserted into 20-cm-deep holes at 0. 5 m × 0.5 m spacing and under field conditions potato seed tubers were set at 30-cm-depth with a 0.6 m × 0.6 m spacing. A 2 × 2 × 2 factorial experiment was laid out in a randomised complete block design, with the eight treatments replicated 7 times. Nemarioc-AL (A), Nemafric-BL (B) and Mormodica (M) phytonematicides served as first, second and third factors, respectively. At 56 days after applying treatments, the A1B1M1 interactions were not significant on all plant variables under greenhouse and field conditions however under microplot the interaction was significant (P ≤ 0.05) on fresh tuber mass, fresh root mass and dry root mass, contributing 28, 26 and 26% in Total treatment variation (TTV) of the respective variables. In contrast, the A1B1M1 xxviii interactions were highly significant (P ≤ 0.01) on chlorophyll content, contributing 43 and 40% in TTV. Generally, relative to untreated control, the second and first order interactions, along with individual treatments, significantly increased fresh tuber mass by 31% relative to the untreated control, except for Nemarioc-AL × Mormodica and Nemafric-BL × Mormodica interactions which were not different to the untreated. The A0B1M1 interaction was highly significant on plant height, stem diameter, chlorophyll content, dry shoot mass, dry root mass and fresh tuber mass, contributing 45, 36, 37, 35, 60 and 35% in TTV of the respective variables under greenhouse conditions similar to the microplot experiment, the interaction relative to the untreated control, also did not have any effect on plant variables. However, under field conditions the first order interaction, A0B1M1, was highly significant on dry root mass, contributing 60% in TTV on the variable. Relative to untreated control, the interaction reduced dry root mass by 14%, which was not different to the effect of Mormodica phytonematicide at 13%, but was significantly different to that of Nemafric-BL phytonematicide. A1B0M1 interaction had significant effects on fresh tuber mass, contributing 33% in TTV on the variable. Relative to the untreated control, the interaction increased fresh tuber mass (yield) by 32%, which was not different to that of Nemarioc-AL phytonematicide at 40%, but significantly different to that of Mormodica phytonematicide at 16%. Nemafric-BL and Mormodica phytonematicides under greenhouse conditions, each reduced dry shoot mass by 18 and 22%, respectively, whereas their interaction effects on the variable did not differ significantly from the untreated control. Similarly, under microplot conditions Mormodica phytonematicide alone significantly reduced plant height by 12%, although this was not different from the effects of Nemafric-BL phytonematicide. Also, the effects of Nemafric-BL phytonematicide on plant height was not different to that of the untreated control. However, Mormodica phytonematicide increased FSM, xxix DSM and FTM by 31, 33 and 19%, respectively. Mormodica phytonematicide effect on the variables was significantly different to the untreated control. The phytonematicide also reduced FRM and DRM by 17% and the effect on the two variable which significantly differed from the untreated control. The second order interaction were not significant on nematode variable under greenhouse and field conditions, but the interaction was significant only on total nematodes in roots, reproductive potential (RP) and final population (Pf) of Meloidogyne species on roots of potato plants and in the soil under microplot conditions, contributing 11, 13 and 10% in TTV on the variables, respectively. Relative to untreated control Nemarioc-AL × Nemafric-BL × Mormodica phytonematicide interaction reduced total nematode, RP and PF by 18, 64 and 18%, respectively, whereas their effects on the variables differed significantly from untreated control. Generally, Nemafric-BL × Mormodica interaction consistently in all three experiment reduced all nematodes variables. Nemarioc-AL × Nemafric-BL × Mormodica interactions were only significant on Na, contributing 7% in TTV o the variable. Relative to untreated control the interaction reduced Na by 33% and effects on the variable was significantly different to those of untreated control also Nemarioc-AL, Nemafric-BL and Mormodica alone. However, the second order interactions were not significant in greenhouse and field conditions. The A0B1M1 first order interaction although the interactive effects, contributed highly in TTV on Na and Zn in potato tuber tissues, relative to untreated control, the effects were rather negligent at 2 and 4%, respectively. In all different conditions of the study validating that potato seed tubers could be used as carriers of active ingredients of phytonematicides when used through the priming technology. The Nemafric-BL and Mormodica phytonematicide interactions consistently reduced population densities of the Meloidogyne species and increased yield under microplot and field experiments.
15

Bud dormancy in developing tubers of yellow nutsedge altered by benzyladenine, gibberellic acid, and abscisic acid applications /

Villamar, Wilson Alvarado January 1980 (has links)
No description available.
16

Structural comparation of cereal and tuber amylopectins

Gutierrez P., Beatriz. January 1985 (has links)
Call number: LD2668 .T4 1985 G875 / Master of Science
17

Topinambo (Helianthus tuberosus L.) gumbų kokybės rodiklių vertinimas ontogenezės ciklo metu / The Evaluation of Jerusalem Artichoke (Helianthus tuberosus L.) Tuber Quality during their Ontogenesis

Kupčiūnaitė, Karolina 13 June 2014 (has links)
Darbo objektas– topinambų gumbų veislės: 'Albik', 'Rubik', 'Sauliai'. Darbo tikslas – įvertinti topinambų (Helianthustuberosus L.) gumbų cheminės sudėties kitimą jų vegetacijos laikotarpiu. Darbo metodai – Topinambų gumbų cheminės sudėties tyrimai atlikti Aleksandro Stulginskio universitete Maisto žaliavų, agronominių ir zootechninių tyrimų laboratorijoje. Eksperimentas buvo atliktas 2012 m. Petro Tiknevičiaus ekologiniame ūkyje, kuris yra Alytaus apskrityje, Varėnos rajone, Geidukonių kaime, pietrytinėje Lietuvos dalyje, smėlingoje Dainavos aukštumoje ir Eišiškių plynaukštėje. Atliktas dviejų veiksnių eksperimentas: veiksnys A – topimanbo veislė, veiksnys B – gumbų vystymasis ontogenezės ciklo metu (mėnesiai). Mėginiai imti 8 kartus: kovo, balandžio, gegužės, birželio, rugpjūčio, rugsėjo, spalio, lapkričio mėnesisias. Topinambų gumbuose standartizuotais metodais nustatyta cheminė sudėtis: sausųjų medžiagų, tirpių sausųjų medžiagų, vitamino C, žalių proteinų, žalios ląstelienos, žalių pelenų, nitratų ir kalio kiekiai. Tyrimų duomenys statistiškai apdoroti dviejų veiksnių dispersinės analizės metodu, apskaičiuotas mažiausias esminis skirtumas (R05). Paskaičiuotas koreliacinis priklausomumas, bei determinacijos koeficientas naudojant kompiuterinę programą Stateng. Paskaičiuoti vidurkiai ir standartiniai nuokrypiai. Darbo rezultatai: 'Albik' veislės gumbuose esmingai daugiausiai sausųjų medžiagų (25,3%) nustatyta lapkričio mėnesį, t.y. XII organogenezės etapo metu, o tirpių... [toliau žr. visą tekstą] / Object of the research: varieties of Jerusalem artichoke tubers “Albik“, “Rubik“, “Sauliai“. Research methods: the analysis of chemical structure of Jerusalem artichoke tubers was performed in the laboratory of Raw Materials for Food, Zootechnical and Agronomical Analysesat AleksandrasStulginskis University. The experiment was carried out in 2012, the place of the experimentwas PetrasTikneviciusorganic farm located in Alytus region, Varena district, Geidukoniai village. The village is located in the South East part of Lithuania, in sandy uplands of Dainava region and plateau of Eisiskes. A two- factor experiment was carried out: the factor A was represented by the variety of Jerusalem artichoke, whereas the factor B indicated the development of the tubers during the cycle of ontogenesis (months). The samples were taken eight times: in March, April, May, June, August, September, October, and November. The following chemical structure of Jerusalem artichokes was determined through the application of standardized methods: the amount of dry matter, soluble dry matter, vitamin C, crude proteins, crude cellulose, crude ash, nitrates and potassium. Processing of the data of the analysis was carried out through the application of the method of Dispersive analysis; the minimum essential difference (R05) between two factors was calculated. Correlation dependency and the ratio of determination were calculated through the application of computer program Stateng. Averages and... [to full text]
18

The effect of growth regulating compounds on physiological aging in potato tuber tissue

Melinder, Richard George. Chasson, Robert M. Nadakavukaren, Mathew. January 1969 (has links)
Thesis (Ph. D.)--Illinois State University, 1969. / Title from title page screen, viewed Aug. 24, 2004. Dissertation Committee: Robert M. Chasson, M.J. Nadakavukaren (co-chairs), Arthur D. Bond, John L. Frehn, David F. Weber. Includes bibliographical references (leaves 106-114). Also available in print.
19

Scutellonema bradys as a pathogen of yam in Benin

Baimey, Hugues Kossi 25 October 2006 (has links)
Please read the abstract on Chapter 5. / Thesis (PhD (Microbiology and Plant Pathology))--University of Pretoria, 2007. / Microbiology and Plant Pathology / unrestricted
20

Porovnání produkční schopnosti vybraných odrůd brambor v ekologickém a konvenčním systému pěstování / Production capacity of selected potato varieties in organic and convention growing

HOŠKOVÁ, Jana January 2015 (has links)
The dissertation investigated on the base of smallparcelled land the production abilities of chosen varieties of potatoes with different lenght of vegetation period in conventional and ecological system. The aim was to evaluate the yield of the tubers, weight of tubers, number of tubers under bunch, number of tubers with a proportion of market value tubers, amount of starch and amount of nitrates on the base of reached results of one years field experiment based on ecological and conventional grown system. The chosen varieties were divided in germinated and non germinated variantions in small parcelled experiment. It was found out that content of nitrates was by both grown technologies under hygienic limit. The lower values were reached in ecological grown system. The determinated starch content of tubers did not prove the differencies between varieties and growing system and it was determinated by 14 %. The conventional technology was better evaluated by yielded elements. Very early variety Magda non germinated showed from chosen varieties enhanced yield of tubers in ecological grown system and it was defined to 87 % of conventional yield for determinated variety. The whole number of tubers in ecological system reached 82 % of conventional technology. Positive influence of germinated seedlings was proved by the yield of consuming tubers. Despite the ecological way of growing was less productive in all evaluated criteria it has very important position in potatoes offer in the market.

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