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Linda McMahan

The science of botany is often daunting to people who are training to become Master Gardener volunteers. However, the range of natural diversity of plants as well as practical information about plant anatomy are essential foundations for other parts of Master Gardener training. I will present a botany module that I have developed over the past 5 years. The module focuses on relevance to the trainee and builds on basic information to examine more complex aspects of botany, all in the space of the 3–6 hours often allotted for basic botany training. It begins with a “tour” of the plant kingdom and plant relatives like algae and fungi, mosses, liverworts, and ferns. I follow this with basic morphology of stems, roots, and leaves; this basic morphology is used to answer the question of how water and minerals move from the soil into and throughout plants, even reaching the height of the tallest tree. A short segment on mycorhizzae reinforces water and mineral transport, while providing a link to the plant kingdom tour. The mycorhizzal section also reinforces or complements training on soils, which is often presented in another portion of the training schedule. Finally, a segment on flowers introduces basic terminology and winds up a discussion of how to recognize monocotyledons and dicotyledons. Several optional hands-on activities help active learners assimilate the information and provide needed reflective time for more traditional learners. The module has been adopted as the official OSU Extension Master Gardener™ Program botany module in Oregon.

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Sauveur Mahotiere and Clarence Johnson Jr.

Mary Washington, UC157F1, and UC157F2 asparagus cultivars were grown from 1-year-old crown under greenhouse conditions in 30-liter pots containing Pro-Mix medium. The roots were cut to 10 cm prior to planting on 12 Feb. 1991. On July 12, 1991 the plants were transferred outdoors and sprayed with BA, GA4/7 and Promalin at 400 mg. liter-1 using tap water as control. On July 16, 1991 the treated ferns were cut at ground level and the plants were returned to the greenhouse, and arranged in a RCB design. Seven reps with one pot/rep were used. Data on time of emergence of first shoots were recorded daily until all pots had produced at least 1 shoot. When all plants had sprouted, cumulative number of all shoots/pots was recorded weekly thereafter over 5 weeks. BA and Promalin reduced time of emergence of shoots and increased the number of shoots/plant. GA4/7 had no effect on shoot emergence or shoot number.

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Aaron J. Brown

Polyethylene glycol (PEG) was evaluated for its influence on hardening of in vitro-propagated `Fern' strawberries (Fragaria ×ananassa) when applied just before transplanting. Strawberries were micropropagated via shoot tips and grown in vitro until roots were well developed. Plantlets were then transferred onto filter paper bridges in liquid medium with 15% (w/v) of PEG-8000. After treatment in the medium for various periods, the plants were compared to the control (no PEG) for water loss from detached leaves, stomatal aperture, and survival rates after transplanting. Leaf epicuticular wax was also quantified. Overall, the in vitro PEG treatment was not successful in significantly increasing hardiness and survivability of the strawberry plants after transplanting from in vitro conditions to a soil medium. Osmotic stress was created, but apparently not for the time needed to increase survival. Further tests are needed to pinpoint the proper exposure time required to increase hardiness and survivability after transplanting plantlets. To increase survival, the time exposed to PEG should be 15, 18, or possibly 21 days.

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David E. Yarborough and Timothy M. Hess

Three hundred, 1 m2 plots with either 0%, 25%, 50%, 75% or 100% dogbane or bracken fern weed cover were used in the study. The experimental design was completely randomized with two species, three treatments (mow, wipe and untreated), five densities and 10 replications. One half of each plot had weed cover and one half was kept weed free in order to compare the effect of weed density on yield. Plots were treated with either 10% v/v glyphosate in a hand held weed-wiper, mowed with a string trimmer or left untreated. Wiping was more effective than mowing for reducing weed numbers in the following year. However, wiping reduced yields compared to mowing at higher weed densities. Mowing proved more effective at increasing yields up to 50% weed cover compared to wiping or not treating. Averages from 1991 and 1992 study indicate mowing increases yields compared to wiping up to 50% then tend to decline, but yields remain greater than not treating.

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Melinda S. Conner and Gerald Klingaman

Studies were undertaken to compare plant growth and water use in a new commercially produced media that contained a hydrophilic polymer combined with a traditional peat-lite media. Rooted cuttings of nephytis, spathiphyllum, parlor palm, pothos, corn plant, `Dallas' fern, and gold dust dracaena were planted into 15cm plastic pots containing either a peat-lite media or the media with hydrophilic polymer. Both mediums were amended with 2.4 kg/m3 gypsum and then treatments of 0, 1.5, or 3 kg/m3 of dolomitic limestone were added. Plant height, width, growth index, top fresh weight and dry weight were measured. Preliminary tests indicated that the media with the hydrophilic polymer performed better with slow-release fertilizer than a constant liquid fertilization program. Plant growth appeared to be optimum at the 0 or 1.5 kg/m3 rate of dolomite. Plants grown in the media with the hydrophilic polymer produced plants of comparable quality to those in the peat-lite media.

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D. J. Makus and J. R. Morris

Supplemental calcium supplied foliariy as Ca glutarate, soil incorporated as gypsum, fertigated as CaNO3, in 3-way combination, or none at all, had no effect on fruit firmness, as measured by shear, reduced fruit decay by as much as 23%. over controls (1986-1988), and generally improved fruit Ca levels only in the combination treatment of 904 kg/ha. Fruit raw product quality (pulp pH, acidity, soluble solids concentration, and Hunter color values) were not consistently affected, although there were significant interactions between cvs Fern and Cardinal, harvest dates, holding time, and years. Supplemental Ca reduced fruit size, but tended to increase yield. In 1988, individual fruits were partitioned into upper/lower, dermal/interior, and upper/lower seeds (6 parts), Ca was the third most abundant mineral nutrient in receptacle tissue, but most abundant in seeds. Highest Ca levels were found (descendingly) in the seed, dermal, and interior pulp tissue, Ca was higher in the upper (stem) end. Differences in fruit Ca levels between cvs were found in the seeds and not the receptacle. No clear relationship was observed between fruit firmness, decay, and Ca level.

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W.A. Bergfield, D.N. Sasseville, R.J. Kremer, and T. Souissi

Pesticides are used extensively in ornamental production. Studies of repeated pesticide applications indicate that microbial changes occur in the rhizosphere of the plant. In addition to controlling the target pest, often a population shift of bacteria may occur. This has been previously shown in research associated with leatherleaf fern [Rumohra adiantiformis (Forst.) Ching] and the fungicide benomyl. Rhizobacteria (root-associated bacteria) of anthurium (Anthurium andraeanum) were investigated with respect to total populations and isolates that are potentially phytotoxic. The anthurium sample roots were taken from commercial Jamaican production sites. The sites had either a benomyl or non-benomyl history. Rhizobacterial populations were estimated by dilution plating and subcultures were taken for a phytotoxicity bioassay. Micrographs of samples were prepared to examine treatment effects on the morphology of roots. Rhizobacteria populations were frequently at 106 colony forming units per gram fresh weight. Consistently, greater than 50% of the isolates from each treatment were potentially phytotoxic. However, in the benomyl history samples, there was a greater diversity of phytotoxic isolates.

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Han Yulin and Wan Jingli

Three-river Plain, the key agriculture and animal husbandry developing region of China is located in the northeast part of Heilongjiang province. There were rich resources of wild ornamental plants in Three-river Plain. 134 species of those were investigated belonging to 54 families. 35 were woody plants and 99 herbaceous. The domestication and cultivation of several plants with high decorative value were studied and briefed as follows: (1) Vibrunnum sargenti Koehne propagates by seeds beginning to blossom in 3 years and by rhizome. The plants grown in the plain are subject to insect pests: (2) Sambucus buergeriana Blume propagates by seeds after sand cultivation for 4-6 months and begins to blossom in the next year; (3) Acanthopanax Senticocus (tupr. et (maxim) harmes propagates by seeds, shoot layering and root cutting. The germination of seeds is lower and the shoot layering is best. It grows slowly in the white clay soil, (4) Hemerocallis midendorffii Tranty. et Mey, propagates by seeds and suckers and blossoms in the next year, growing well in the plain; (5) Ostrich fern (Matteuccia struthiopteris (L.) Todaro) propagates by spore. The spore grows to sporophyte in 70-90 days after sowing and the sporophyte grows to sporophyll in 4 years.

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Yves Desjardins, André Gosselin, and Michel Lamarre

Asparagus (Asparagus officinalis L.) transplants and in vitro-cultured clones were grown and acclimatized under two photosynthetic photon flux (PPF) conditions (ambient and ambient + 80 μmol·s-1·m-2) and three atmospheric CO2 concentrations (330, 900, and 1500 ppm). Short- and long-term effects were measured in the greenhouse and after two seasons of growth in the field, respectively. In the greenhouse, CO2 enrichment (CE) and supplemental lighting (SL) increased root and fern dry weight by 196% and 336%, respectively, for transplants and by 335% and 229%, respectively, for clones. For these characteristics, a significant interaction was observed between SL and CE with tissue-cultured plantlets. In the absence of SL, CE did not significantly increase root or shoot dry weight. No interaction was observed between CE and SL for transplants, although these factors significantly improved growth. It was possible to reduce the nursery period by as much as 3 weeks with CE and SL and still obtain a plant size comparable to that of the control at the end of the experiment. Long-term effects of SL were observed after two seasons of growth in the field. Supplemental lighting improved survival of transplants and was particularly beneficial to in vitro plants. Clones grown under SL were of similar size as transplants after 2 years in the field.

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Eric Hinesley and John Frampton

Orthotropic shoots (tips of primary axes) from 3-year-old Fraser fir seedlings [Abies fraseri (Pursh) Poir.] were grafted onto rootstocks of Fraser fir, Korean fir (A. koreana Wils.), momi fir (A. firma Sieb. & Zucc.), Nordmann fir (A. nordmanniana (Steven) Spach.), Turkish fir (A. bornmuelleriana Mattf.), and West Virginia balsam fir from Canaan Valley (Canaan fir) [A. balsamea (L.) Mill. var. phanerolepis Fern.]. Firstyear survival in the greenhouse was 92% to 98% except for momi fir (83%). The percentage of grafted plants with orthotropic shoots was 92% to 98%, except for Korean (81%) and momi fir (86%). Plants were subsequently established in replicated field experiments on three sites in the piedmont and mountains of North Carolina. In general, leader elongation of grafted Fraser fir scions was greater than leader growth on nongrafted transplants, including Fraser fir. Differences in survival appear to reflect interspecific variation in resistance to phytophthora root rot and/or tolerance of warm environments. Grafting may offer the potential to grow Abies Christmas trees on previously unsuitable sites, or to reclaim or continue using sites already seriously impacted by root rot.