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Mana Libran and David J. Williams

Leca clay pebbles were characterized and tested as a possible growing-medium for use in floriculture production systems that recycle irrigation water. Leca clay pebbles are light porous particles made by heating clay. X-ray diffraction tests indicate that high manufacturing temperatures (1100C) result in final particles composed primarily of quartz. Water-holding capacity was determined by pressure plate apparatus at eight pressures. Leca particles that were 4 to 8 mm retained more water than particles sized 12 to 18 mm. The bulk density of the particles were 0.43 and 0.37 g/cc for the 48-mm and the 12- to 18-mm particles, respectively. The pH of the leca particles was 7.77. The cation exchange capacity of the leca particles was relatively low compared to a standard soilless growing medium of 1 pine bark: 1 peat: 1 perlite (by volume). Leca particles have a CEC of o.82 me/100 g Ca and 6.36 me/100 g K, where the CEC of the previously mentioned soilless.medium was 24.21 me/100g Ca and 30.08 me/100 g K. Leca clay pebbles were tested as growing medium for the production of geraniums (Pelargonium hortorum) stock plants.

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David J. Williams and Rhonda Ferree

The State Of Illinois passed legislation banning landscape wastes deposition in land fills. Approximately 18% of all solid wastes going into Illinois landfills were landscape wastes including grass clippings, branch prunings, leaves and wood. A cooperative program between the Horticulture Department, the Cooperative Extension Service and the Illinois Department of Energy and Natural Resources was initiated to train county extension advisers, municipalities, and the consuming public on methods for landscape waste reduction and recycling.

Workshops, video tapes, Master Composters, mobile displays, fact sheets and a model municipal composting facility were developed. Publications and other educational materials will be displayed.

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David J. Williams and Michelle Antoinetti

Newspaper was pelletized and tested as a peat moss substitute in growing media used for producing bedding plants and woody ornamentals in containers. Varying amounts of urea was added to the newspaper prior to pelletization to improve the C:N ratio of the pellets Newsprint had a C:N ratio of 800:1. One quart of a 28% nitrogen solution per ton of paper consistently changed the C:N ratio to 400: 1 Additional quantities of the 28% N solution did not lower the C:N ration due to volatilization. The addition granular urea at 5.0 lbs. and 10.0 lbs. of urea per 300 lbs of newsprint altered the C:N ratio to 50:1 and 18:1 respectively. Media containing pelletized paper expanded about 40% in volume when water was added Following the first leaching electrical conductivity of the leachate was slightly elevated when compared to the check. In nine subsequent leachings the electrical conductivity was not significantly different than the check. The pH of the leachate averaged 7.2

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Rhonda J. Ferree and David J. Williams

Under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), private applicators who purchase and use restricted use pesticides (RUP's) are required to obtain certification. The Cooperative Extension Service has been assigned the responsibility of informing and educating those applicators about the safe and precise use of pesticides. In Illinois, area Agriculture advisors are responsible for the training. They are supported by State staff. Support is provided to area advisors through development of several teaching medias. A Private Applicator Training manual is the main educational media. That is supported by a slide set and script, videos, demonstration kits, handouts, and overheads. Trainers are encouraged to have students use workbooks, which were developed to follow the slide set, during training sessions. Additional support is provided through a newletter, equipment and video loans, advertising, meeting site rental, and yearly program updates. Train-the-Trainer classes are provided as needed. Trainers have been surveyed as to the quality of exiting and the need for new educational materials. Examples of publications and teaching materials will be on display.

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Karim H. Al-Juboory and David J. Williams

Shoot tip explants of Algerian Ivy Heder a canariensis were cultured on MS basal medium supplemented with a combination of salt strength and NAA and IBA. More roots per explant developed on full salt strength medium combined with NAA. The most roots per explant were obtained with a combination of IBA and 1/4 MS salt. There was an inverse relationship between an increase in IBA or NAA concentration and root length and number. Shoots proliferated better on full MS salt combined with NAA and IBA. The highest level of NAA (40 uM) and 0.1 uM TDZ produced the most shoots and roots, the longest roots, the highest rooting percentage, the largest plants with the most leaves and the best callus quality per explant. The leaves from in vitro were cultured on MS medium with varying levels of Thidiazuron (TDZ) and NAA in the presence of light produced the highest number of roots.

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David J. Williams and Karim H. Al-Juboory

The objective of this study was to evaluate the ability of various cultivars of Hosta ovary explants to generate adventitious shoots and obtain variegated plants in vitro. Immature inflorescences along with 8 to 10 cm of scape were harvested from Hosta cultivars. The ovaries were prepared for culture by cutting immature florets before anthesis. The florets were first cut just above the top of the immature ovary to remove the sigma, style, corolla, and anther. Then the calyx and filament bases were also removed. Ovaries were transversely cut into halves and transferred to baby jars containing Hosta initiation medium supplemented with naphthaleneacetic acid (NAA) at 0.5 mg/L and 6-benzylamino purine (BA). The explants produced adventitious shoots from ovary base via organogenesis. The number of shoots regenerated from shoot tips and callus increased linearly with repeatedf subculturing on MS medium. This method would provide an effective alternative to conventional propagation crown division of Hosta, an expensive and slow process. The long-term goal of this project is to improve Hosta.

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Kandy L. Walker and David J. Williams

Experiments in two consecutive years indicated that barnyardgrass (Echirzochloa crusgalli L.), large crabgrass (Digitaria sanguinalis L.), and giant foxtail (Setaria faberi Herrm.) reduced growth of container-grown `San Jose' juniper (Juniperus chinensis L. `San Jose') 83 days after transplanting grass seedlings into the containers. Grass densities of one to six weeds per container reduced `San Jose' juniper growth. By 83 days of grass interference, juniper shoot dry weight was reduced as much as 43% by six weeds per container.

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Karim H. Al-Juboory and David J. Williams

Shoot tip explants of Algerian Ivy Heder a canariensis were cultured on MS basal medium supplemented with a combination of salt strength and NAA and IBA. More roots per explant developed on full salt strength medium combined with NAA. The most roots per explant were obtained with a combination of IBA and 1/4 MS salt. There was an inverse relationship between an increase in IBA or NAA concentration and root length and number. Shoots proliferated better on full MS salt combined with NAA and IBA. The highest level of NAA (40 uM) and 0.1 uM TDZ produced the most shoots and roots, the longest roots, the highest rooting percentage, the largest plants with the most leaves and the best callus quality per explant. The leaves from in vitro were cultured on MS medium with varying levels of Thidiazuron (TDZ) and NAA in the presence of light produced the highest number of roots.

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Karim H. Al-Juboory and David J. Williams

Three node stem cuttings of Algerian Ivy Hedera canariensis were sprayed with growth regulators to incipient runoff under greenhouse conditions. The results demonstrated that the combination of BA + GA4+7, (Promalin) promoted branching of Algerian Ivy better than applications of BA or GA4+7 alone. Plants treated with Atrinal developed more shoots per node than those treated with GA4+7, BA, or Promalin. Increasing concentration of Atrinal from 0 to 3000 ppm, also reduced branch length and leaf number for both pinched and unpinched plants. 2,3,5—triodobenzoic acid (TIBA) significantly increased the branching of Algerian Ivy, although plant shape was not commercially acceptable due to epinasity of the foliage.

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David J. Williams and Karim H. Al-Juboory

University of Illinois, Department of Horticulture, Plant Science Lab, 1201 S. Dorner, Urbana, IL.

Calli were initiated from immature inflorescences of selected cultivars of Hosta in the light on Hosta initiation medium (Carolina Biological Supply Company, 1986). Three cultivars, Francee, Birchwood Park's Gold, and Wide Brim Sum & Substance, produced microshoots. The calli were compact and green in color. The highest percentage of callus formation occurred with the Francee cultivar. Nakaiana, Golden Edger, Golden Scepter, Obscura, Sum & Substance, and Shade Fanfare produced only calli. The calli were transferred to modified Murashige and Skoog salts. The media containing 5 × 5 factorial combinations of NAA and BA (0.0, 0.1, 0.5, 1.0, or 2.0 mg/l). The results show that media with NAA at 1.0 and 2.0 mg/l in combination with BA from 0.5 to 2.0 mg/l produced the highest number of microshoots per explant.