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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

Manipulating rooting of micropropagated plants

Nicholas, Julian January 1990 (has links)
No description available.
2

Rooting patterns, water use and productivity in wheat, rye and triticale

Khan, M. F. January 1989 (has links)
No description available.
3

Root systems of oilseed and pulse crops-morphology, distribution and growth patterns

Liu, Liping 10 July 2009
This study determined the key characteristics of temporal patterns of root growth during the crop development period, as well as the vertical patterns of root distribution in the soil profile for important oilseed and pulse crops grown on the semiarid Canadian Prairie. Rooting characteristics greatly influence the nutrient acquisition and water-use patterns for any plants. However, crop root systems have not been studied intensively due to time, labor and costs constraints. In the literature, root studies mostly focus on cereal crops and very limited information is available for oilseeds and pulses even though these broadleaf crops are critical in the diversification of cropping systems. Thus the objectives of this study were to 1) examine the root morphological characteristics, root distribution patterns in the soil profile, and the fine root distributions of oilseeds and pulses in comparison with wheat; 2) to determine the rhizospheric properties of pulse crops. In 2006 and 2007, canola (<i>Brassica napus</i> L.), flax (<i>Linum usitatissimum</i> L.), mustard (<i>Brassica juncea</i> L.), chickpea (<i>Cicer arietinum </i> L.), field pea (<i>Pisum sativum</i>L., lentil (<i>Lens culinaris</i>), and spring wheat (<i>Triticum aestivum</i> L.) were grown under low- (natural rainfall) and high-water (rainfall+irrigation) conditions in southwest Saskatchewan. Roots were sampled at the seedling, early-flower, late-flower, late-pod, and physiological maturity growth stages, and root parameters determined using image analysis. The growth of roots progressed markedly from seedling to late-flowering and then declined to maturity. Root growth of pulse crops was not significantly affected by water conditions, but canola had 70% greater root length, 67% more root surface area, and 79% more root tips under high-water than under low-water conditions. At the late-flower stage, over 70% of the roots in oilseeds and pulses were distributed within the 0-60 cm soil profile and the largest proportion (around 50%) were found in the top 20-cm of the soil depth. About 85% of the roots in oilseeds and pulses were classified as extra fine (diameter <0.4mm). The rhizosphere fungi were significantly different among tested pulses and also pulse rhizosphere fungi were significantly affected by soil depth but not by water conditions. Inoculation of <i>Penicillium bilaiae</i> (product -JumpStart®) to the pulse crops increased the amount of the fungi in their rhizospheres by as much as 42% compared to the pulses not inoculated. Results from this study are novel and provide the baseline for model-related studies on water use and nutrient uptake by root systems of oilseed and pulse crops in semiarid environments.
4

Root systems of oilseed and pulse crops-morphology, distribution and growth patterns

Liu, Liping 10 July 2009 (has links)
This study determined the key characteristics of temporal patterns of root growth during the crop development period, as well as the vertical patterns of root distribution in the soil profile for important oilseed and pulse crops grown on the semiarid Canadian Prairie. Rooting characteristics greatly influence the nutrient acquisition and water-use patterns for any plants. However, crop root systems have not been studied intensively due to time, labor and costs constraints. In the literature, root studies mostly focus on cereal crops and very limited information is available for oilseeds and pulses even though these broadleaf crops are critical in the diversification of cropping systems. Thus the objectives of this study were to 1) examine the root morphological characteristics, root distribution patterns in the soil profile, and the fine root distributions of oilseeds and pulses in comparison with wheat; 2) to determine the rhizospheric properties of pulse crops. In 2006 and 2007, canola (<i>Brassica napus</i> L.), flax (<i>Linum usitatissimum</i> L.), mustard (<i>Brassica juncea</i> L.), chickpea (<i>Cicer arietinum </i> L.), field pea (<i>Pisum sativum</i>L., lentil (<i>Lens culinaris</i>), and spring wheat (<i>Triticum aestivum</i> L.) were grown under low- (natural rainfall) and high-water (rainfall+irrigation) conditions in southwest Saskatchewan. Roots were sampled at the seedling, early-flower, late-flower, late-pod, and physiological maturity growth stages, and root parameters determined using image analysis. The growth of roots progressed markedly from seedling to late-flowering and then declined to maturity. Root growth of pulse crops was not significantly affected by water conditions, but canola had 70% greater root length, 67% more root surface area, and 79% more root tips under high-water than under low-water conditions. At the late-flower stage, over 70% of the roots in oilseeds and pulses were distributed within the 0-60 cm soil profile and the largest proportion (around 50%) were found in the top 20-cm of the soil depth. About 85% of the roots in oilseeds and pulses were classified as extra fine (diameter <0.4mm). The rhizosphere fungi were significantly different among tested pulses and also pulse rhizosphere fungi were significantly affected by soil depth but not by water conditions. Inoculation of <i>Penicillium bilaiae</i> (product -JumpStart®) to the pulse crops increased the amount of the fungi in their rhizospheres by as much as 42% compared to the pulses not inoculated. Results from this study are novel and provide the baseline for model-related studies on water use and nutrient uptake by root systems of oilseed and pulse crops in semiarid environments.
5

Effect of Rooting Media, Cultivars and Genotype on the Propagation of Blueberry

Saha, Tripti 12 August 2016 (has links)
The objectives of this research were to study: 1) the effects of five different propagation media containing composted materials on the rooting of semi hardwood blueberry cuttings and 2) the effects of four cultivars and one genotype on rooting responses of these cuttings. The media used were: peat moss and horticulture grade per lite as control, composted pine bark fines with only one-time application of ammonium nitrate, pine bark fines with composted cotton gin waste, hardwood with and composted chicken litter and pine bark with composted chicken litter. There were no significant differences among the media for rooting from semi hardwood cuttings. Cultivars or genotype, media, and the interaction of individual media and cultivar or genotype had effect on rooting responses. Climax and Tifblue showed higher number of rooting from cuttings compared to other lines. Climax had the highest number of callus and survival percentage among all.
6

Spatial analysis of the formation of adventitious shoot meristems /

Tian, Hui-Cheng 01 January 1992 (has links) (PDF)
No description available.
7

Rooting techniques for selected tree species

Laubscher, Charles Petrus January 1999 (has links)
Thesis (MTech (Horticulture))--Cape Technikon, Cape Town, 1999 / Vegetative propagation techniques for rooting of cuttings of indigenous tree species, i.e. Olea europaea subsp. African, Podocarpus falcatus, Syzigium cordatum and introduced species, i.e. Acacia mearnsii, A. melanoxylon, Eucalyptus grandis and Melia azedarach were studied and improved at the Cape Technikon nursery from May 1994 to June 1998. These tree species are considered problematic since the indigenous species produce unwanted fruits in urban areas which attract frugivores, while the introduced species are a threat to indigenous vegetation and natural habitats, though they are of great commercial value. The progress in mutation breeding of sexual sterility in most of the problematic species created a need to propagate them vegetatively. Without cloning of seedless species, their beauty and economic value to South Africa will be lost, as the indigenous species will be neglected, while invasive species will continue to threaten the natural habitat of indigenous species. Experiments were conducted to test age, type and length of cuttings, environmental factors, growth season, hormone application, various treatments and rooting media for each of these species. This study showed that relatively few publications relevant to the vegetative propagation of indigenous tree species are available. However, some introduced species, e.g. Eucalyptus grandis, are propagated successfully for commercial forestry purposes. Ficus sur and Syzicium cordatum showed the highest rooting success, i.e. 85-90%, followed by Olea europaea subsp. africana (75-80%), and Podocarpus falcatus (60%). The introduced species showed no rooting success, however, callusing in Eucalyptus grandis (35-61%), and Melia azedarach (50%), and survival rates in Acacia mearnsii (10%) and A. melanoxylon (20%) were achieved. Treatments, i.e. etiolation, placing plants under stress, sealing basal stems of cuttings, and fungicide treatments all showed positive results in promoting callusing success. The study showed that rooting success in individual species are directly related to the growth stage of parent plants as well as the season during which the cuttings were taken. With progress towards successful vegetative propagation of sterile problem plant species, propagators and horticulturists can in future apply these improved techniques. These plants will then continue to supply timber, fire wood and improve aesthetics in the South African urban environment.
8

The control of rooting of MM106 apple tree rootstocks

Campen, R. January 1988 (has links)
No description available.
9

The performance and rooting of eucalyptus grandis x nitens cuttings.

Murugan, Nelisha. January 2007 (has links)
Hybrid clones of Eucalyptus grandis and E. nitens (GN) have consistently been shown to be suitable for planting in cold, dry, marginal plantation sites, where they exhibit high yields and superior pulp properties. However, their clonal propagation is hindered by the very poor rooting success of cuttings. The present study aimed at assessing the effect of cutting type, time of year of setting cuttings and Seradix 2 application on rooting and development of cuttings of a commercially important Eucalyptus grandis x Eucalyptus nitens clone (GN107). Cuttings were prepared from clonal hedge coppice at the Mondi Business Paper, Trahar Technology Centre, Hilton. Three cutting types were used (cut at different distances from the node) for each terminal (situated below the apical bud) and non-terminal cuttings. The leaves were trimmed and, for half the cuttings, the base of the stem of cuttings were dipped in Seradix 2 rooting powder (3 g kg-1 4-(indole-3-yl)-butyric acid (IBA). They were then placed into rooting trays (128 inserts/ tray arranged as 8 rows x 16 columns). Seradix 2-treated and Seradix 2-untreated terminal and non-terminal cuttings, cut at, above and below the node (twelve treatments in total) were set in trays with one treatment per column of eight replicates, per tray. There were nineteen trays overall. The trays were filled with peat, perlite and vermiculite (3:3:1) and were maintained in a Mondi greenhouse, with air temperature at 25°C to 27°C (thermostatically activated fans), root zone temperature at 28°C (bed heaters) and 20 second misting at 10 minute intervals (automatic misters). The study was carried out in November 2005, April 2006 and June 2006. In the first experiment, both terminal and non-terminal cuttings were used; thereafter only non-terminal cuttings were used. The plantlet yield was very low, regardless of cutting type, Seradix 2 treatment and the time of year the cuttings were set. The highest plantlet production (12.5%) and rooting frequencies (13.8%) were achieved with non-terminal cuttings treated with Seradix 2. Although not statistically significant, Seradix 2 inhibited shoot production (31.4% for Seradix 2-untreated and 24.2% for treated cuttings). The position at which inserts were cut in relation to the node did not significantly affect the number of plantlets produced and non-terminal cuttings appeared hardier and performed better than terminal cuttings. The time of year of setting cuttings did not have any significant effect on plantlet yield, nonetheless, plantlet yield was highest in cuttings set in November (9.2%) and lowest in April (0.4%). In addition, cuttings set in November (spring), had superior shoot development in terms of the number of cuttings that produced shoots (regardless of root production), shoot length and the mass of shoots relative to root mass. The highest percentages of cuttings that produced roots (regardless of shoot growth) (10%) and the highest number of roots per cutting (2) were part of the June trial. Therefore, cuttings set in June (winter) had superior root development as compared with cuttings set in November (spring) or April (autumn). In all of the studies, three rooting patterns were observed in cuttings: roots produced only from the cut area only (type 1), only from the sides of the stem (type 2) and from both sites (type 3). Non-terminal cuttings treated with Seradix 2 showed a higher incidence of types 2 and 3 rooting patterns than the terminal cuttings. Seradix 2 application increased the prevalence of types 2 and 3 rooting patterns. Although not statistically different, cuttings dipped 2.5 cm into Seradix 2 produced more types 2 and 3 rooting patterns than cuttings dipped at the abaxial end only. Light microscopy of stem sections of cuttings indicated that roots appeared to originate from the xylem archs as well as from the cambium. The collected data indicate that it is necessary to continue research towards improving the efficiency of plantlet production of GN107 via cuttings. It appears that cuttings of this clone may be set throughout the year and that terminal cuttings should be avoided. In addition, the present practice at the Mondi Hilton nursery of treating cuttings with Seradix 2 needs to be reconsidered as although it increases rooting, it does not increase plantlet production due to its apparent inhibitory effect on shoot development. / Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2007.
10

Square rooting by iterative multiply-additions

Ito, Masayuki, 高木, 直史, Takagi, Naofumi, Yajima, Shuzo 09 December 1996 (has links)
No description available.

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