Search Results
Abstract
Foliar application of 6-benzylaminopurine (BA) to Ilex crenata cvs. Helleri and Rotundifolia increased the number of axillary shoots per plant. ‘Helleri’ axillary shoot number was increased 4 times by 500 ppm BA whereas axillary shoot number of Rotundifolia was increased 1.5 and 3 times by 100 and 500 ppm respectively. Leaf size and shoot length were significantly reduced by 500 ppm BA.
Abstract
‘Burfordii’ holly was grown at day/night temperature combinations of 26°/22°, 22°/18° and 18°/14°C under either a long photoperiod (LD = 9 hours + 3 hours dark interruption) or short photoperiod (SD = 9 hours). The number and growth of new shoots were significantly greater at 26°/22° than at 22°/18° and no shoot growth occurred at 18°/14°. Leaf size was significantly smaller at 26°/22° than at 22°/18°. Holly shoot growth was greater under LD than SD. No significant temperature-photoperiod interaction was observed.
Abstract
Inflorescence development and fruit set of ‘Burford’ holly was rapid at a day/night temperature of 26°/22°C and progressively slower at 22°/18° and 18°/14°. The number of flowers to set fruit, however, was increased at lower temperatures for both long photoperiod (LD = 9 hours + 3 hours dark interruption) and short photoperiod (SD = 9 hours). At 22°/18°, SD increased fruit set over LD. No significant temperature-photoperiod interaction was observed. A greater number of vegetative shoots developed as temperature increased and mean shoot length was correlated with the number of flowers to set fruit.
Abstract
The effects of 3 nitrogen levels and 2 growth regulators on growth of winter- and summer-rooted cuttings of Ilex crenata cv. Helleri were studied. Nitrogen applications promoted bud break immediately after rooting on summer cuttings and also enhanced the growth of winter-rooted cuttings. Generally, plants grown at 300 or 150 ppm N had greater shoot numbers and length, height, width, and dry weight compared to plants grown at 50 ppm N. Also spring growth of these liners was markedly enhanced by the higher level of N applied the previous season. Benzyladenine (BA) at 600 ppm increased the number of breaks and suppressed stem length, while gibberellic acid (GA3) at 400 ppm decreased the number of breaks and increased stem length.
Abstract
Rooted linears of Ilex crenata Thunb. ‘Helleri’ and ‘Rotundifolia’ were grown in polyvinyl chloride pipe sections from which longitudinal sections could be removed for root observations. Plants were fertilized at either 150 or 300 ppm N with a 20N–8.7P–16.5K soluble fertilizer. Rate of root and shoot growth was determined through 2-3 flushes of growth by taking weekly measurements of shoots and roots. Root growth of both cultivars was episodic in nature with active root growth usually preceding a shoot growth flush by 1 to 2 weeks. This growth pattern was observed in both fertility levels.
Abstract
Determinations of carbohydrates in the plant organs of Rhododendron spp. cv. ‘Sweetheart Supreme’ and ‘Hexe’, were made by chemical analysis, thin-layer chromatography (TLC) and gas-liquid chromatography (GLC). Reducing sugar content was 1.5 times higher in buds than in leaves for ‘Hexe’ with no significant differences for ‘Sweetheart Supreme’. Reducing sugars were also higher in the roots than stems with both cultivars. Sucrose content was 1.4 times greater in leaves than in buds of ‘Hexe’ and 1.6 times greater in ‘Sweetheart Supreme’. Starch was significantly higher in leaves and buds than in stems and roots. The predominant soluble sugars identified by TLC and GLC were sucrose, glucose, and fructose. Small but detectable amounts of raffinose and maltose and an unidentified compound were also found in the plant organs.
Abstract
Ilex cornuta ‘Burfordii’ holly plants were maintained at 3-4°C for 0, 2, 4, 6 or 8 weeks. Following these treatments, the number of flowers to develop were greatest on plants receiving 6 or 8 weeks of chilling. Time required for flowering to begin and the duration of flowering was shortened by the longer exposures to cold treatment
Abstract
‘Burford’ holly (Ilex cornuta Lindl. et Paxt. cv. Burfordii) differentiates primordia in September which were subsequently identified as flowers. The pistillate flower only partially differentiated by early winter and consisted of a pedicel, 2 bracts, 4 petals, and 4 stamens. Completion of flower differentiation and anthesis occurred in the spring.
Abstract
Higher N rates applied to Ilex crenata‘ Helleri’ holly liners grown in the greenhouse increased shoot growth but-decreased root growth resulting in a greater shoot:root ratio. Higher N rates reduced the time required for a shoot growth flush to occur. Ρ at 85-500 ppm had no effect on shoot or root growth. Continued growth of liners at 50 ppm N lowered the shoot:root ratio due to stimulation of root growth while 300 ppm N caused the shoot:root ratio to increase due to increased shoot growth.
Abstract
Ilex crenata ‘Helleri’ liners were greenhouse grown in sand culture and subjected to N rates which ranged from 14 to 108 ppm in one experiment and from 70 to 250 ppm in a second experiment. Maximum shoot dry weights occurred at 87 ppm N in the first experiment and at 100 ppm N in the second experiment. The number of plants per treatment initiating visible shoot elongation 17 days after the initiation of the fertilizer treatments was influenced by N treatment and 79% of the differences in final dry weights could be attributed to the time of visible shoot elongation initiation. The maintenance of 87–100 ppm N in the substrate nutrient solution, the range at which no further increase in shoot dry weight occurred, would maximize plant growth and most effectively utilize the applied fertilizer.