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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.
1

Parasites and predators of Dendroctonus ponderosae Hopkins (Coleoptera : Scolytidae) in ponderosa pine /

Billings, Ronald Forrest. January 1970 (has links)
Thesis (M.S.)--Oregon State University, 1970. / Typescript. Mounted photographs. Includes bibliographical references (leaves 67-73). Also available on the World Wide Web.
2

Pine litter as substrate for propagation of vegetable transplants in trays

Mphaphuli, NS, Van Averbeke, W, Bohringer, R 18 March 2005 (has links)
The study evaluates the potential of pine litter for use as a substrate in the propagation of vegetable transplants in trays. Sub-optimum pH and electrical conductivity of pine litter were addressed by incorporating 10 % feedlot manure by volume. The water holding capacities of pine litter and the pine litter-feedlot manure mixture were higher than the minimum required, but their air filled porosities were below optimum. The pine litter-feedlot manure mixture reduced the germination percentages of cabbage seedlings by 17 % and lettuce seedlings by 13 % relative to composted pine bark, but the germination percentage of tomato seedlings was similar in both substrates. There were no significant differences in the growth of vegetable transplants between the two substrates. In both substrates increasing nutrient availability by adding controlled-release fertilizer had similar positive effects on the growth transplants. Substrate-nutrient availability interactions were only observed in dry shoot mass of lettuce seedlings and dry root mass of tomato seedlings. Composting the pine-litter animal manure mixture could possibly improve the observed low germination percentage of vegetable transplants in pine litter.
3

Studies related to: bark extractives of western white pine; and synthesis of indole alkaloids

Eigendorf, Günter Klaus January 1974 (has links)
Part I of this thesis describes the structural elucidation of eleven triterpenes isolated from the benzene extract of Western white pine (Pinus monticbla Dougl.) bark. Chemical and detailed spectroscopic investigations revealed the presence of a common tetracyclic A9(ll)-lanostene skeleton in all of the investigated materials. Structural variations were found at the C3 position and in the side chain at C17. The following assignments have been made: compound I, 33~methoxy-5a-lanost-9(ll)-en-24S,25-diol (43); compound II, the corresponding 33-hydroxy derivative (51); compound III, 33-methoxy-5a-lanost-9(11)-en-24-one (59); compound IV, 33-methoxy-5a-lanost-9(11),25-dien-24S-ol (65); compound V, 3a-hydroxy-5a-lanost-9(ll),25-dien-24-ol (66); compound VI, 33-methoxy-5a-lanost-9(ll)-en-22,25-diol (70); compound VII, 33-methoxy-26,27-bis nor-5a-lanost-9(ll)-en-24-one (71). Compound VIII was shown to be the ethylidene derivative of 33-methoxy-5a-lanost-9(ll)-en-24S,25-diol (76) and compounds IX and X were assigned to structures (78) and (80), respectively. A novel dimeric steroidal structure (83) has been proposed for compound XI. Part II describes synthetic investigations which lead to the development of a sequence providing a synthon [(193) and (194)] for the synthesis of vobasine (78)- and sarpagine (77)-type alkaloids. 2-Amino-3-indolyl(3a)-propanol (121), obtained by lithium aluminum hydride reduction of L-tryptophan (106), was converted to its ditosylate (150). Treatment of the latter with cyanide ion provided 3-(N~tosylamino)-4-indolyl(3a)-butanonitrile (151) which was transformed to 3-(N-tosylamino)-4-indolyl(3a)-butanoic acid (152) by means of 30% sodium hydroxide solution. 3-Amino-4-indolyl(3a)-butanoi.c acid methyl ester (155) was obtained through reductive cleavage of (152), followed by Fischer esterification. Compound (155) could then be converted to 3-CN-.formylami.no)-4- (N-benzyl-indolyl)(3a)-butanoic acid methyl ester (163) by treatment with a mixture of formic acid and acetic anhydride followed by sodium hydride and benzyl bromide. Reaction with trifluoroacetic acid converted compound (163) to the tricyclic 3-carbomethoxymethyl-N -benzyl-3,4-dihydrocarboline (173) which upon condensation with 3-methylene-pentan-2-one (126) afforded the tetracyclic 2-oxo-3-ethyl-6-carbomethoxymethyl-l,2,3,4,6,7,12,12b-octahydro-(N-benzylindolo)(2,3-a)-quinolizine (175). The ethylene ketal (177) of the latter material was treated with diisopropyllithium amide and methyl chloroformate to provide 2-oxo-3-ethyl-6-dicarbomethoxymethyl-l,2,3,4,6,7, 12,12b-octahydro-(N-benzylindolo)(2,3-a)-quinolizine ethylene ketal (178), which possesses a highly activated acidic proton (C6a) in the side chain. A suitable leaving group at the C2 position, necessary for subsequent transannular cyclisation, was available through conversion of the tetracyclic ketone (175) to the corresponding C2cx-alcohol (181) and further transformation of the latter into various derivatives such as the acetate (182), the mesylate (183) and the p-nitrobenzoate (185). In order to allow generation of an exocyclic olefin at C3, the C2-olefin, 3-ethyl-6-carbomethoxymethyl-l,4,6,7,12,12b-hexahydro-(N-benzylindolo)(2,3-a)quinolizine (184), obtained via dehydration of the alcohol (181), was converted to 2,3-a-dihydroxy-3-ethyl-6-carbomethoxymethyl-l,2,3,4,6,7,12,12b-octahydro-(N-benzylindolo) (2,3-a)-quinolizine (186) by osmium tetroxide oxidation. Treatment of (186) with acetic anhydride or p-nitrobenzoyl chloride provided the diacetate (187) or the C2 mono p-nitrobenzoate (188), respectively. The 10-membered ring system, present in the vobasine skeleton, became availahle through reductive cleavage of the C/D ring junction in the tetracyclic alcohol (181), thus, affording 2a-hydroxy-3a-ethyl-N^-methyl-6-carhomethoxymethyl-l,2,3,4,6,7,12,12b,12b-nonahydro-(N-benzyl-indolo)(2,3-a)-12b,N^-seco-quinolizine (190). Acetic anhydride treatment of the ethylene ketal (177) provided two isomeric components, 2-oxo-3-ethyl-Nb-acetyl-6-carbomethoxymethyl-1,2,3,4,6,7,12,12b-octahydro-12b-acetoxy-(N-benzylindolo)(2,3-a)-12b,Nb-seco-quinolizine ethylene ketal (191a and b), also possessing the 10-membered ring skeleton. Furthermore, the latter materials enable an entry into the family of 2-acylindole alkaloids as well as members of the dimeric alkaloids such as voacamine (75). / Science, Faculty of / Chemistry, Department of / Graduate
4

Performance of ancymidol as influenced by pine bark in the container media /

Bhat, N. R. January 1982 (has links)
No description available.
5

Iron and manganese requirements of containerized plants growing in pine bark

Leda, Carol E. January 1986 (has links)
Three species of woody plants, Ilex crenata 'Helleri', Juniperus chinensis procumbens 'Nana', and Ligustrum lucidum, were grown in one-liter containers filled with pine bark to determine Fe and Mn requirements with regard to rate and ratio. FeEDTA and MnEDTA were applied at either a 2:1 or 1:2 ratio of Fe:Mn at 5 concentrations each, 3 times per week with each irrigation. Medium solutions were collected every 21 days on one species and analyzed for Fe and Mn levels. Dry weight and tissue Fe and Mn levels were determined for all three species. Neither rate nor ratio of applied Fe and Mn had an effect on shoot dry weights. Control treatments, in general, had the lowest medium solution and tissue levels of Fe and Mn, however, there was no difference in dry weights between control and treatment plants. These results suggest that pine bark supplies adequate levels of Fe and Mn for growth under the conditions of this study. In a second study, three sources of Fe and Mn were applied to Tagetes erecta 'Inca' growing in 500 cc plastic pots containing sieved pine bark at 3 lime rates: 0, 3, and 6 kg m⁻³. Sources of Fe and Mn were pre-plant Micromax, liquid sulfate salts, and liquid chelates applied in the irrigation water. No difference in growth between micronutrient sources was detected, however, growth was greater at the 3 and 6 kg m⁻³ lime rates. Levels of Fe and Mn in medium solution and tissue decreased with increasing lime rate, with availability of Fe and Mn greatest with chelate as the source, regardless of lime rate. A similar study was conducted with a control and liquid sulfate treatment. There was no difference in dry weight between the sulfate treatment and the control, except at 0 kg m⁻³ lime where the control plants were larger. Again, lime additions increased growth, and Fe and Mn availability in medium solution and tissue levels decreased. These results suggest that if Fe and Mn additions are needed, all sources provide adequate Fe and Mn for growth. / M.S.
6

Effect of Micronutrient Rate on the Growth of Containerized Quercus palustris Seddlings in Pine Bark

Kelk, Lisa 05 February 2003 (has links)
The objectives for this research were to determine: 1) the rate of Micromax which will produce maximum growth of pin oak (Quercus palustris Munchh.), a landscape tree which has shown a previous growth response to the addition of Micromax at the manufacturer's recommended rate, 2) which micronutrient(s) is most associated with maximum growth, and 3) the rate of Cu, Fe, Mn, and Zn required to produce maximum growth of Quercus palustris. Q. palustris seedlings were container-grown in pine bark amended with the following rates of Micromax: 0, 0.15, 0.3, 0.6, 0.9, 1.8, or 2.7 kg(m-3 in 2000, 2001, and 2002. For all three years, the maximum growth was obtained at rates near the manufacturer's recommended rate of 0.9 kg(m-3. A micronutrient mix was formulated by increasing the levels of Zn, Mn, Fe, and Cu individually while holding the other micronutrients constant based on the grams of each micronutrient contained in Micromax at 0, 0.15, 0.3, 0.6, 0.9, 1.8, or 2.7 kg(m-3 for 2001 and 0, 0.45, 0.9, or 1.8 kg(m-3 for 2002. In addition, Cu, Fe, Mn, and Zn were also applied alone to pine bark at rates of 0, 0.45, 0.9, or 1.8 kg(m-3 without the addition of any other micronutrients. Holding all other micronutrients constant and increasing the rate of one micronutrient did not increase growth. However, when Cu, Fe, Mn, or Zn was added to pine bark alone at increasing rates, growth increased. For Cu and Zn, the growth increased was linear suggesting that a higher rate of Cu and Zn than that provided by Micromax at the manufacturer's recommended rate might be advantageous. / Master of Science
7

Sulfur Requirements of Container-grown Pin Oak and Japanese Maple

Browder, Jake Forrest 03 December 2004 (has links)
The objectives for this research were to determine: 1) whether sulfated micronutrient addition increased growth of container-grown pin oak (Quercus palustris MuÌ nchh) and Japanese maple (Acer palmatum Thunb.) seedlings by supplying micronutrients, sulfur, or decreasing substrate pH, 2) S requirements of Q. palustris and A. palmatum container-grown in a pine bark (PB) substrate, and 3) if there are any conditions that will affect these S requirements. Container grown Q. palustris and A. palmatum seedlings were grown in PB, amended (or not) with the following treatments: control (no amendment), Micromax (commercial micronutrient fertilizer [sulfate form]), K2SO4, H2SO4, HCl, chelated micronutrients, elemental S, or CaSO4. Dry weights of plants in all treatments supplying S were higher than for plants receiving no S. These data indicate that S, not micronutrient application, was the primary cause of increased growth from the addition of sulfated micronutrients. In other experiments these two species were fertilized with 8 different concentrations of S application (0, 1, 2, 5, 10, 20, 40, or 80 mg·liter-1). Regression analysis revealed dry weights of both species were near maximum at the extrapolated application concentration of 30 mg·liter-1 S, which corresponded to approximately 15 and 7 mg·liter-1 S in substrate solution for oak and maple, respectively. In another set of experiments plants were fertilized with Micromax or FeSO4 with or without lime. In the plus lime treatments (substrate pH 6.1), plant dry weights were higher in Micromax fertilized plants than for FeSO4 fertilized plants. However, in the minus lime treatment (substrate pH 4.5), FeSO4 addition effectively supplied S to plants. / Master of Science
8

Investigating the natural history and predator complex of the native pine bark adelgid (Pineus strobi) in southwestern Virginia

Wantuch, Holly Anne 27 February 2018 (has links)
The pine bark adelgid, Pineus strobi (Hemiptera: Adelgidae) is a native herbivore of eastern white pine, Pinus strobus (Pinales: Pinaceae), in eastern North America. It is a sessile insect that settles on P. strobus and inserts its stylet bundle to feed on the tree’s phloem. Although P. strobi is not considered a serious pest, it shares its range with the invasive hemlock woolly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae). Predators introduced as biological control agents of A. tsugae interact with P. strobi and its native predators, including Laricobius rubidus LeConte (Coleoptera: Derodontidae). Prior to this study, little work had been done to document the phenology or predators of P. strobi, particularly in its southern range. In the present study, the phenology of P. strobi is reported in southwestern Virginia. Patterns in overwintering population dynamics varied notably from those described from this species’ northern range. The number of annual generations could not be measured due to overlap following two distinct spring generations. Adult body size varied seasonally and was greatest in the spring. Variation between observations from the northern and southern ranges of P. strobi indicate phenological plasticity that informs biological control efforts and offers insight into implication of climatic effects on population dynamics of this and related species. Arthropod predators associated with P. strobi in forests of southwest Virginia were collected during a two-year survey. Morphology and DNA barcoding were used for identification. Species of predators found included: Laricobius rubidus (Coleoptera: Derodontidae), a native adelgid specialist, and two species from the dipteran family Chamaemyiidae, Leucopis piniperda Malloch and L. argenticollis Zetterstedt, which are adelgid specialists. Members of the families Cecidomyiidae, Coccinellidae, Chrysopidae, Hemerobiidae, and Syrphidae were also recovered. Most diverse were the Cecidomyiidae, with 15 different species inferred from their DNA barcodes. Additional work was performed to quantify supercooling points of L. rubidus collected from November – December 2016. These will be compared to those of other Laricobius species in a parallel study. Knowledge of this predator complex is beneficial to describing P. strobi ecology, and also with regard to potential biological control of invasive adelgids in the same region. / Ph. D.
9

A comparison of growth media on cyclamens in a controlled environment

Adriaanse, Pierre 08 July 2014 (has links)
Cyclamens are deemed an essential cold season crop for supplementing the income of commercial growers during winter. However, cyclamens have the reputation of being a demanding commercial crop mainly due to difficulty in successful crop cultivation, lengthy production time and production costs. The economic and environmental landscape in South Africa dictates that careful consideration be given to reducing production time and costs, but still improving the quality of the commercial crop for market readiness. Growth medium are considered an important factor contributing significantly to the quality of commercially grown container cyclamens in a controlled environment. The focus of this study was on establishing the most suitable growth medium for commercially grown cyclamens in a South African environment in order to improve the quality of the commercial crop. Only one F1 variety of cyclamen was used as the sample population with a sample size of five plants per growth medium mixture planted according to a randomised block design in a specified area within a greenhouse. Seven commercially available growth medium mixtures, five locally available and two imported, were subjected to a typical production cycle of commercial cyclamens in a controlled greenhouse. The growth medium mixtures for comparison were Cyclamen Mix; 45 Mix; 50% Cyclamen Mix - 50% 45 Mix; 49 Mix; 7 Mix; coarse coir; Klasmann base 4 Substrate mix . The measuring instrument used in the study was adapted from existing instruments used in the comparison of cyclamens and growth medium. It included various measurements and observations: Plant height, plant diameter, plant weight, number of leaves, leaf width, foliage fresh weight, number of flowers, diameter of tuber and root fresh weight. The results obtained in the comparison determine the most suitable growth medium for container cyclamens for South African circumstances. The physical properties of peat retain water for a longer time which is beneficial for the production of container cyclamen. The results of this study therefore indicate that growth mediums containing peat performed better than mediums containing no peat. / Agriculture and  Animal Health / M.Sc. (Ornamental Horticulture)
10

A comparison of growth media on cyclamens in a controlled environment

Adriaanse, Pierre 08 July 2014 (has links)
Cyclamens are deemed an essential cold season crop for supplementing the income of commercial growers during winter. However, cyclamens have the reputation of being a demanding commercial crop mainly due to difficulty in successful crop cultivation, lengthy production time and production costs. The economic and environmental landscape in South Africa dictates that careful consideration be given to reducing production time and costs, but still improving the quality of the commercial crop for market readiness. Growth medium are considered an important factor contributing significantly to the quality of commercially grown container cyclamens in a controlled environment. The focus of this study was on establishing the most suitable growth medium for commercially grown cyclamens in a South African environment in order to improve the quality of the commercial crop. Only one F1 variety of cyclamen was used as the sample population with a sample size of five plants per growth medium mixture planted according to a randomised block design in a specified area within a greenhouse. Seven commercially available growth medium mixtures, five locally available and two imported, were subjected to a typical production cycle of commercial cyclamens in a controlled greenhouse. The growth medium mixtures for comparison were Cyclamen Mix; 45 Mix; 50% Cyclamen Mix - 50% 45 Mix; 49 Mix; 7 Mix; coarse coir; Klasmann base 4 Substrate mix . The measuring instrument used in the study was adapted from existing instruments used in the comparison of cyclamens and growth medium. It included various measurements and observations: Plant height, plant diameter, plant weight, number of leaves, leaf width, foliage fresh weight, number of flowers, diameter of tuber and root fresh weight. The results obtained in the comparison determine the most suitable growth medium for container cyclamens for South African circumstances. The physical properties of peat retain water for a longer time which is beneficial for the production of container cyclamen. The results of this study therefore indicate that growth mediums containing peat performed better than mediums containing no peat. / Agriculture and  Animal Health / M.Sc. (Ornamental Horticulture)

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