bluuebunny/crossref_metadata_2025 huggingface dataset:
CHRONIC OZONE EXPOSURE AFFECTS FREEZE RESISTANCE IN CITRUS AND AVOCADO
Authors: Eissenstat D. M. , Syvertsen J. P.
Published: February 2019

The effects of elevated levels of ozone on growth, mineral nutrition and freeze resistance were studied using broadleaf-evergreen citrus and avocado trees. `Ruby Red' grapefruit (Citrus paradisi L.) trees on either Volkamer lemon (Citrus volkameriana Ten. & Pasq.) or sour orange (Citrus aurantium L.) rootstock and `Simmonds' or `Pancho' avocado trees (Persea americana Mill.) on the rootstock `Waldin' were exposed to ozone in open-top chambers for 4 mo in 1988 and in a second experiment in 1989 for 8 mo. Citrus tree growth, estimated by total leaf mass, was unaffected by ozone concentrations of 3 times ambient in either year but avocado growth was reduced by ozone concentration at 2 times ambient in 1989. All trees were well-fertilized and ozone had little effect on mineral nutrient concentrations in leaves. Freeze resistance, estimated by electrolyte leakage from leaf disks and survival of leaves, stems, and whole-plants following exposure to freezing temperatures, was often diminished in avocado and citrus at 3 times ambient ozone, but occasionally was increased at 2 times ambient. Thus, ozone can be related to shifts in freeze resistance that can occur prior to discernible growth effects.
PROTEIN PATTERNS DURING GERMINATION OF Lactuca sativa `Empire'.
Authors: Still David W. , Bradford Kent J.
Published: February 2019

Lettuce seeds were germinated at 20 C in the dark in water and sampled at various intervals during the first 18h of germination to determine quantitative and qualitative differences in proteins. The soluble protein fraction was partitioned into albumins and globulins by dialysis and the proteins of the globulin fraction were visualized by SDS-PAGE. Heat stable proteins were obtained by boiling the proteins, cooling on ice, and resuspending in buffer.

The soluble protein content remained constant during the first 8h of germination. Thereafter protein content decreased and was 6% of the amount present in unimbibed seed in 21 day old seedlings. The ratio of heat stable to heat unstable proteins decreased during the germination process. No differences in banding patterns were observed when the soluble protein fraction were run on SDS-PAGE. However, on gels run with the globulin fraction a 57 kD protein appeared 4 and 8 h after imbibition and had disappeared by 12 h after imbibition. The role of proteins and heat-stable proteins during germination and prevention of dessication during early seedling growth is discussed.
INTERNAL BROWNING IN `ATLANTIC' POTATO TUBERS AS AFFECTED BY CALCIUM, IRRIGATION, AND STRAW-MULCHING
Authors: Roberts C.R , Knavel Dean E. , Snyder John , Jones Terry , Spalding Dave
Published: February 2019

Internal brown spot (IBS) was found consistently in the `Atlantic' cultivar at Lexington in 1967, 1968 and 1989, and at Owensboro and Quicksand, KY in 1987, Treatments of foliar and soil applied CaSO4 in 1987, soil-applied CaSO4 in 1988, and straw mulching in 1989 did not reduce IBS. Irrigation increased IBS because of larger tubers and increased Ca content of plants as compared with non-irrigated plants. Tubers showing IBS had higher Ca content in affected tissue than in non-affected tissue. Both IBS and Ca content of leaves increased as the plants aged.
STAYMAN FRUIT CRACKING AS RELATED TO CW COMPOSITION
Authors: Weiser Russell L.
Published: February 2019

Stayman apples are predisposed to cracking. Trees whose trunks were scored and foliage sprayed with GA4+7, NAA 800, and Vapor Guard had significantly fewer apples crack than controls. The skin strength and stretch distance were the same for control and treated apples. However, slices of treated apple expanded significantly more than control apples when immersed in distilled water for 45 minutes. During this treatment the amount of water taken up was not significantly different, which may indicate the difference lies in the cell structure. Hypodermal cells of control apples appear to be more elongated and have thicker cell walls than treated apples. Cell wall sugar and amino acid components will be measured to see if this discrepancy can be attributed to cell wall structural properties. These results suggest that stayman cracking occurs when the expansion of the hypodermic cannot keep pace with expansion of the fruit. It is further hypothesized that this difference is due to a difference in cell wall composition and consequent effect on wall extensibility.
ASEXUAL PROPAGATION OF SHEPERDIA CANADENSIS AND SHEPERDIA ROTUNDIFOLIA
Authors: Krishnan Sarada , Shultz Kurt , Hughes Harrison
Published: February 2019

In recent years there has become an increased demand for native, drought-tolerant species for private landscaping and revegetation of disturbed sites; especially in the Rocky Mountains and high plains states. Sheperdia canadensis and S. rotundifolia, native to much of this area, have already increased in popularity due to their drought tolerance and general hardiness. Micropropagation and rooting of cuttings have been investigated for these two species. S. canadensis hardwood stem cuttings were successfully rooted with 0.8% IBA at 46.5% as compared to less than 5% from previous research. S. rotundifolia produced a greater number of axillary shoots on WPM as compared to MS medium and at a moderate concentration of BA.
WATER REQUIREMENTS OF WOODY LANDSCAPE SHRUBS
Authors: Klett James E. , Wilson Carl
Published: February 2019

Four woody plant species were grown during the 1988 and 1989 growing seasons under three irrigation treatments at two sites in two soil types. The three irrigation treatments which were implemented included: 1) control, 2) drip irrigated with no water stress, and 3) drip irrigated with water stress. Rainfall and additional water applied during the 1988 and '89 growing seasons were recorded. Analysis of this data showed the no stress treatment receiving more water at both sites, especially in 1989. After two years of growth, no statistical differences in new growth (height) were observed with any plant species evaluated at either site from the three water treatments. Comparing new growth, no statistical differences were observed except with Juniperus sabina. No visual differences were observed with Ribes alpinum and Cornus sericea. Visual differences were observed with Potentilla fruticosa and Juniperus sabina. The experiment will be continued during the 1990 growing season.
TIMED FERTILIZER APPLICATIONS EFFECT DWARF YAUPON HOLLY GROWTH AND FERTILIZER UTILIZATION
Authors: Yeager Thomas H.
Published: February 2019

Multiple branched liners of llex vomitoria were greenhouse-grown in 3-liter containers with a common nursery medium and received either 2.5 g N surface-applied in 1 application as Osmocote (18N-2.6P-10K) or a total of 0, 0.5, 1,5 or 2.5 g N per container from a solution that contained N, P and K in a ratio of 6:1:3. The solution fertilizer was applied either 1, 2, 3 or 4 times per week with total N applied per container equally divided among individual applications, After 26 weeks, shoot dry weights were greatest for plants that received 2.5 g of N as either 2 soluble applications per week or as Osmocote applied once at the beginning of the experiment. Plants that received 1.5 g of N applied 4 times per week had similar shoot dry weights. Nitrogen uptake will be calculated to determine if 4 applications par week resulted in greater utilization than 2 applications par week or 1 application of Osmocote during the growing season.
FOLIAR NUTRIENT–COMPOSITION OF DENDRANTHEMA GRANDIFLORA TZVELEV. `SPEARS' IN RESPONSE TO INCORPORATED APPLICATIONS-OF CONTROLLED-RELEASED FERTILIZERS
Authors: Owings Allen D. , Meadows Warren A. , Fuller Donald L. , Stewart Melinda R.
Published: February 2019

Recent studies at Louisiana State University evaluated incorporated rates (0.72, 1.08, and 1.44 kg N/m3) of controlled-release fertilizers (Chrysanthemum Mix 12N-4.4P-14.1K, Osmocote 14N-6.1P-11.6K, and Nutricote Type 70 14N-6.1P-11.6K) on the foliar nutrient composition of `Spears' potted chrysanthemums. Recently mature leaf tissue was sampled at flowering and analyzed for N, P, K, Ca, Mg, Fe, Zn, Cu, and Mn.

Increasing application rates reduced Ca and M g content in leaf tissue, while N, P, and K increased with an increase in application rates. Chrysanthemum Mix 12N-4.4P-14.1K provided more K to leaf tissue than did Osmocote or Nutricote Type 70 14N-6.1P-11.6K.
THE EFFECTS OF GROWTH REGULATORS ON FLOWERING, BRANCHING PATTERNS AND GROWTH OF NEW GUINEA IMPATIENS
Authors: McKnight J. Phillip , Klingaman G. L.
Published: February 2019

Eighteen New Guinea impatiens cultivars were evaluated for performance as bedding plants and for suitability as hanging basket plants. The cultivars were treated with three growth retarding chemicals (B-9, Sumagic and Cutless) to determine their effect on plant growth, branching and overall flower development. Two applications of 2500 ppm B-9 produced the most commercially acceptable plants. Height and spread were reduced by approximately 30 percent with no reduction in the number of flowers produced or the number of days to bloom. Cutless and Sumagic applications reduced growth approximately 50 percent and delayed blooming as much as 2 weeks when compared to the untreated control. Growth regulator treatment had no effect on the number of branches produced except with Sumagic which resulted in an overall reduction in branching.
BIOLOGICAL PEST CONTROL WITH CONTINUOUS GREENHOUSE CULTURE
Authors: D'Angelo Anthony J. , Quinn James
Published: February 2019

A strategy for controlling pests with biological control was sought for production of salad greens and herbs in a nutrient film technique (NFT) growing system. A case study was initiated in October 1989 using a one half hectare greenhouse range (1988 construction) with no past or present synthetic insecticide use. Problematic pests were aphids and thrips. A natural predator/pest cycle (NPC) area was established (5% of total greenhouse area with potted herbs on benches) to provide an area for predators to establish and reproduce. Introduced predators, which successfully reproduced in the greenhouse, were Apidoletes aphidimyza (aphid control), Amblyseius macKenzie, and A. cucumeris (thrip control), Encarsia formosa (whitefly control), and Phyoseiulus persimilus (two spotted spider mite control), Naturally occuring predators of importance included a wasp parasitoid of aphids (Hymenoptera) and an insect predator, the minute pirate bug (Hemipters, Anthocoridae), which feeds on thrips and aphids.

Two flying predators of aphids (A. aphidimyza and the wasp parasitoid) dispersed well from the NPC area and provided effective control. The technique of applying the thrips predators, a slow moving mite to flats shortly before transplanting provided good dispersal on all transplants. The time for effective control by the predator was 4 to 6 weeks. Effective control was observed in chives but not shorter cycle crops (3 to 5 weeks average). Immature minute pirate bugs were also observed in the chives assisting in control. Effective spider mite control was accomplished 2 to 3 weeks after the release of P. persimills into infested area. Whitefly populations have been effectively controlled by E. formosa.
HORTICULTURAL AND ECONOMIC COMPARISON OF HAND VERSUS MECHANICAL PRUNING IN A HIGH DENSITY FRENCH PRUNE ORCHARD
Authors: Southwick Stephen M. , Krueger W. , Yeager J.T. , Osgood J.
Published: February 2019

French prunes (Prunus domestica L.) on myrobalan seedling rootstock were planted in 1981 in an east-west direction with 4.9 m between rows and 2.7 m between trees on a poorly drained Class II soil in Glenn County, CA. A randomized complete block design was used with 8 trees per plot. Trees were pruned by hand to an open-center tree form or pruned by machine to a pyramid form in the dormant or summer season resulting in 6 pruning treatments. This high density system has led to high yields of good quality fruit (9.18 dry tons/acre in 1989, sized at 78 fruit per pound). Hand pruning led to higher yields, larger fruit, lower drying ratios and a greater dollar return per acre than any of the machine pruned trees. Dormant machine pruning led to larger fruit produced than those trees pruned in the summer by machine. Mechanical pruning may be possible for short time periods, but continued practice led to smaller fruit with lower yields than hand pruning. Certain locations within the tree canopy had smaller fruit size and it is within those lower locations where fruit size needs to be improved. These and additional experimental results obtained from 1987 through 1989 growing seasons will be presented.
USE OF YARD WASTE COMPOST IN POTTING MIXES
Authors: McConnell Dennis B. , Smith Wayne H.
Published: February 2019

Three foliage plants, Dracaena fragrans, Peperomia obtusifolia and Schefflera arboricola were grown in 24 different mixes. Potting mixes were formulated using yard waste compost from two sources, a commercial mix (Metro 300) and a prepared mix (peat: pine bark sand). All potting mixes produced acceptable plants with no phytotoxicity associated with any mix. Only minor differences were discerned in the growth rate of P. obtusifolia and S. arboricola.

The growth rate of D. fragrans showed the greatest response to potting mix formulations. Plants in a standard potting mix (P/PB/S) used in the industry for D. fragrans grew slower than plants in many of the mixes containing various fractions of yard waste compost. Chemical and physical properties of the potting mixes used showed physical properties had the greatest variability. Overall, the best growth for all 3 plants was in a potting mix composed of 87.5% Metro 300/12. 5% YWC#1 and worst growth was in YWC#2 (100% composted (live oak leaves).
GROWTH SUPPRESSION IN DWARF AND SEMIDWARF APPLE ROOTSTOCKS BY UNICONAZOLE
Authors: Saavedra J. Angel , Stang Elden J. , Palta Jiwan P.
Published: February 2019

Uniconazole (UCZ) can control tree size by suppressing tree growth. Growth control of one year-old `Haralred' on MAC 9 `MARK' (dwarf) and EMLA 7 (semidwarf) rootstock was evaluated in the greenhouse. Uniconazole (65 or 130 mg/L) was sprayed 0, 1, 2 or 3 times at 3 week intervals. Total shoot growth was inhibited 31% and 24% on `MARK' and EMLA 7 rootstock, respectively, with 130 mg/L. Rootstock and scion diameter and number of leaves per tree were not affected by UCZ. Total leaf area on `MARK' rootstock increased when UCZ was applied once at 65 or 130 mg/L. On EMLA 7 two 130 mg/L sprays resulted in 22% less total leaf area compared to the control. UCZ applied three times reduced specific leaf weight on EMLA 7 trees 12% compared to the control. Branch angle was increased proportional to UCZ applications on semidwarf rootstock from 40° to 47°, and decreased on dwarf rootstock from 47° to 39°. Stomatal conductance increased 43% on `MARK' with 130 mg/L UCZ applied two times. Net photosynthesis of attached leaves did not differ. All UCZ treatments produced 18 to 56% fewer total flower clusters per tree than the control. UCZ appeared to delay bloom significantly.
SPUR PRUNING `DELICIOUS' APPLE TREES
Authors: Marini Richard
Published: February 2019

Twenty-eight-year-old `Starkrimson Delicious' trees were spur pruned in 1986 and 1987 and/or treated with BA + GA4+7 in 1986 in an attempt to improve spur growth and fruit weight. Yield, fruit weight, and spur quality characters were recorded for 1986-1989. All treatment combinations failed to improve yield or fruit weight. Although spur-pruning improved spur length, spur bud diameter, leaf area per spur and leaf dry weight per spur, fruit weight was not improved. BA + GA4+7 reduced yield and fruit weight, and increased the number of pygmy fruit in 1986, but had little effect on fruiting for the three years after treatment.
TOXICITY SYMPTOMS OF MICRONUTRIENTS COPPER, MAGNESIUM AND ZINC FOR SELECTED BEDDING PLANTS
Authors: Lee Chi Won , Jeong Gye-Soon , Jeong Byoung-Ryong
Published: February 2019

Toxicity symptom of micronutrients copper, magnesium and zinc were investigated for geranium, marigold, vinca and zinnia. Plants were grown in peat-lite mix in 11 cm plastic pots and watered with nutrient solutions containing 0.05, 0.5, 1, 5, 10 mM concentrations of Cu2+, Mg2+ and Zn2+. In most species, the concentrations of these micronutrients higher than 5 mM greatly reduced plant growth and induced stem and foliar toxicity symptoms. Toxic levels of Cu2+ and Zn2+ reduced plant and leaf sizes without producing leaf spots in all species tested. Toxicity symptom of Mn2+ were characterized by numerous chlorotic or brown leaf spots. Visual leaf toxicity symptoms of these 3 micronutrients in each species are illustrated.
FLOWERING OF AESCHYNANTHUS `KORAL' UNDER DIFFERENT PHOTOPERIOD AND TEMPERATURE REGIMES
Authors: Whitton Brooks , Healy Will
Published: February 2019

Aeschynanthus `Koral' plants were grown in photoperiods of 8 to 14 hr (8 hr natural daylight plus 0-6 hr incandescent light of 3 μmolm-2s-1) beginning January, March, or June. The number of weeks to anthesis and number of leaves on shoots reaching anthesis were not affected by photoperiod, but differed when treatments began. Number of shoots reaching anthesis per plant was greatest in photoperiods of 13 hr for treatments beginning January or June. Time of year influenced flowering more than photoperiod, suggesting a temperature interaction. A. `Koral' plants were given photoperiods of 12 or 24 hr (daylight fluorescent lamps at 100 or 50 μmolm-2s-1 respectively) at temperatures of 18 or 24 C. After 8 weeks, 18 C plants had fewer nodes before the first flower bud than 24 C plants. Number of nodes to the first flower bud was decreased under the 24 hr treatments at 24 C, while no difference to photoperiod was observed at 18 C. Flowering of A. `Koral' appears to be promoted by 18 C temperature where the plant behaves as a day neutral plant. At 24 C, A. `Koral' responds as a long day plant.
EFFECTS OF TALL FESCUE TURF ON GROWTH AND NITROGEN FIXATION POTENTIAL OF THE WOODY LEGUME LUPINUS ALBIFRONS
Authors: Wu Lin , Torres Armando
Published: February 2019

The effect of tall fescue turf on growth, flowering, modulation, and nitrogen fixing potential of Lupinus albifrons Benth. was examined for greenhouse and field grown plants. No allelopathic effect was observed for lupine plants treated with tall fescue leachates. The nitrogen-fixing potential measured by nodule dry weight and acetylene reduction rates was not significantly affected by either tall fescue turf or low nitrogen fertilization. Both the greenhouse and field studies showed that the growth, sexual reproductive allocation, and number of inflorescences were significantly reduced when lupine plants were grown with tall fescue. The root length densities of tall fescue turf and lupine monoculture were measured. The tall fescue turf had 20 times higher root length density (20 cm cm-3 soil) than the lupine plants monoculture. This suggests that intense competition at the root zone may be a dominant factor which limits the growth of the lupine plants. The reproductive characters of the lupine plants was improved by phosphorus fertilization. Transplanting of older lupine plants into the turf substantially alleviated the tall fescue turf competitive effect.
DIFFERENCES IN CHILLING AND POST-REST HEAT REQUIREMENT OF VARIOUS PRUNUS SPECIES AND PEACH CULTIVARS (P. PERSICA L. BATSCH)
Authors: Beckman Thomas G. , Okie William R.
Published: February 2019

Differences in chilling and post-rest heat requirements of various stonefruits were investigated through the use of cuttings collected from field grown trees. Materials studied included P. angustifolia Marsh, P. besseyi Bailey, P. maritima Marsh, P. persica (L.) Batsch (`Agua 6-4', `Flordaking', `Pi Tao', `Redhaven', `Redskin', and `Ta Tao'), P. umbellata Ell. and a Japanese type plum (`Byrongold'). Cuttings were collected after natural leaf fall and shortly after the onset of of chill hour accumulation. Cuttings were stored at 4°C. Groups of cuttings were removed from storage after various amounts of chilling and allowed to develop at 16, 21 or 27°C. Cuttings were observed for both vegetative and flower bud break. Magnitude of differences in chilling and post-rest heat requirements and their implications in the breeding of peaches for low and moderate chill areas will be discussed.
CONSUMER PREFERENCE FOR POLYETHYLENE CONTAINERS WHEN PURCHASING ORNAMENTAL TREES
Authors: Purvis L.V. , Behe B.K. , Gilliam C.H. , Adrian J.L.
Published: February 2019

Product packaging influences consumer's purchase decisions, yet this influence is not defined for ornamental horticultural products. The objective of this study was to determine consumer preferences for three types of nursery plant containers: field ball and burlap, fabric bag, and polyethylene. Uniform Magnolia grandiflora and Photinia fraserii (1-2 m) grown in gro-bags ware either containerized in black polyethylene pots, wrapped to simulate traditional ball and burlap, or kept in fabric begs. Seventy-four consumers from Montgomery, Ala., were asked to indicate their preferences. Most (48%) preferred the polyethylene container, followed by the fabric bag (27%), ball and burlap (19%). These data suggest that fabric bags have similar consumer appeal compared to ball and burlap. Plants in polyethylene containers likely appeared healthier and more vigorous because they held more soil, retained more moisture, and gave plants a better appearance.
USAGE OF AND ATTITUDES TOWARD COMPUTERS FOR CUSTOMER-INTERACTIVE MARKETING IN GARDEN CENTERS
Authors: Howell Lauren E. , Dana Michael N.
Published: February 2019

A mail survey was conducted to determine attitudes held by garden center owners/managers about computers as customer-interactive marketing tools. The survey was sent to 220 garden centers in the 7-state North Central Region (IA, IL, IN, MI, MN, OH, WI), who were members of the Garden Centers of America. A response of 46% was received. Ownership of one or more computers was reported by 64% of respondents. Over 50% said they believe there is a place in garden centers for customer-interactive computer usage. Of those who did not agree that there is a place for point-of-sale computer usage in the garden center, the two most common objections were the impersonal nature of computers, and the cost. Survey results will contribute to development of perennial flower garden design software for use in point-of-sale marketing.
RESPONSE OF KIENTZLER NEW GUINEA IMPATIENS TO PINCHING
Authors: Starman Terri Woods
Published: February 2019

Manually pinched plants of 18 cultivars of Impatiens hybrids (Keintzler New Guinea impatiens) were compared to control plants to determine the effect of apical meristem removal on flowering, growth and branching. Pinching delayed days to anthesis (first flower) of all cultivars, however, further delay in days to marketability (5 flowers open) was dependent upon cultivar. Plant area and fresh and dry weight were not affected by pinching plants of any cultivar. Cultivar influenced response to pinching treatments for plant height and plant width. Secondary branch number was increased by approximately 3 branches for all cultivars when plants were pinched. There were interactions between cultivar and treatment for primary, tertiary, and total branch number. Measured improvements in plant form determined two cultivars, Sylvine and Thecla, should be pinched. Chemically pinching these two cultivars with dikegulac at 780 mg·liter-1 was comparable to manually pinching plants.
EFFICACY OF THREE SPECIALTY OSMOCOTE FORMULATIONS (POINSETTIA, POTTED CHRYSANTHEMUM, AND ZONAL GERANIUM)
Authors: Carver S.A. , Tayama H.K. , Prince T.L. , Campbell L.S.
Published: February 2019

Results from a preliminary study (growth parameters and foliar analyses) comparing a new specialty Osmocote formulation (12N-5.5P-12.4K) designed specifically for poinsettias with a standard Osmocote formulation (19N-2.6P-9.9K) revealed that the new formulation provided inadequate levels of nutrients at 1.0× and 1.5× the recommended rate. Average plant height (cm) for plants produced with 1.0× 12N-5.5P-12.4K, 1.5× 12N-5.5P-12.4K, 1.0× 19N-2.6P-9.9K was 33, 34, 37. Average plant diameter (cm) and foliar N content (%) was 42, 46, 53, and 2.8, 3.5, 4.1, respectively. Follow up studies (growth parameters and foliar analyses) comparing replacement shipments of three specialty Osmocote formulations (12N-5.5P-12.4K for poinsettias, 12N-4.4P-14.1K for potted chrysanthemums, and 13N-5.5P-9.1K for zonal geraniums) with Osmocote 19N-2.6P-9.9K and Peter's 20N-4.4P-16.6K injected at 200 mg N per liter of water at every irrigation showed all specialty formulations to be adequate sources of plant nutrients-comparable to the standard Osmocote. Average chrysanthemum height (cm) for plants produced with 1.0× 12N-5.5P-12.4K, 1.5× 12N-5.5P-12.4K, 1.0× 19N-2.6P-9.9K, Peter's 20N-4.4P-16.6K was 30, 30, 30, 29. Average chrysanthemum diameter (cm) and foliar N content (%) was 51, 50, 49, 50, and 4.5, 4.8, 4.4, 5.2, respectively.
RELATIONSHIP OF IRON AND MANGANESE AVAILABILITY IN PEAT-BASED MEDIA TO THE OCCURRENCE OF A SPECIFIC PHYSIOLOGICAL DISORDER IN TAGETES ERECTA
Authors: Halbrooks Mary C. , Albano Joseph P.
Published: February 2019

A specific physiological disorder of the recently matured leaves of Tagetes erecta has been demonstrated to be associated with high levels of iron and manganese in affected tissues. In previous work by the authors, the disorder was inducible and increased in severity with increasing levels of iron DTPA supplied to plants grown in peat-based media, but was much less severe when iron DTPA treatments were applied to plants grown hydroponically. At low concentrations of iron DTPA in solution, the occurrence of the disorder was more closely correlated with increased levels of manganese in leaf tissue than iron, Objectives of this study were to determine the effects of iron chelate (DTPA) on occurrence of the disorder and the availability of iron and manganese in the media in the absence of added manganese. Iron DTPA (1, 5, 15, and 20 ppm) was supplied to two cultivars of Tagetes erecta, `Voyager' and `First Lady', grown in a commercial peat-based media product under controlled environmental conditions. Concentrations of iron and manganese in leachate samples taken weekly, and in symptom and non-symptom tissue at harvest, and the progression of the symptoms in leaf tissue over time. will be discussed.
BLOOM AND RIPENING OF RIBES IN CORVALLIS, OR
Authors: Hummer Kim , Gerten Donna
Published: February 2019

In commercial growing regions the bloom period for currants and gooseberries is critical to crop development because of potentially damaging spring frosts. Breeding programs in northern latitudes include selection for frost avoidance mechanisms such as late blooming tendencies. Corvallis climate is milder than Ribes production regions, with the average winter minimum temperature about 10C and the coldest recorded April temperature of -5C in 1926. The last spring frost occurs by April 14 on average. About 30 cultivars and species selections of currants and about that same number of gooseberries were evaluated for blooming and fruiting at the National Clonal Germplasm Repository. Dates of first bloom, last bloom, first ripening, and last ripening during 1987 through 1989 were collected. The longest ripening period, 93 days, occurred in 1989 on a selection of R. burejense F. Schmidt. The shortest ripening period in 1989 was 70 days, occurring in many black currant cultivars including Black September, Crusader, Coronet, and Invigo. These same cultivars required a range from 62 to 66 days to ripen m 1987. For the years examined thus far, the earliest ripening dates occurred in 1987, starting as early as Julian date 150; the latest ripening date (192, Julian) occurred in 1988. Data from 1990 will be presented. The climate in the Pacific Northwest is favorable for the production of currants and gooseberries.
INFLUENCE OF A SOIL-INCORPORATED HYDROGEL ON IRRIGATION REQUIREMENTS AND QUALITY OF TRANSPLANTED SOD
Authors: Koski Anthony
Published: February 2019

The purpose of this study was to evaluate the effectiveness of soil-incorporated hydrogel to reduce irrigation requirements of transplanted Kentucky bluegrass (Poa pratensis) sod. The treatments included an untilled control, tilled soil, and tilled soil with incorporated hydrogel. Initial irrigation treatment were made daily, at various percentages of potential evapotraspiration (PET), to determine irrigation requirements of newly transplanted sod. Other irrigation treatments were later imposed on transplanted sod which had been established at 100% of PET, to determine irrigation requirements of established sod. Turf quality was measured weekly, and sod transplant rooting strength was also measured.
NOTCHING TECHNIQUES TO INCREASE BRANCHING OF YOUNG APPLE TREES
Authors: Greene Duane W. , Autio Wesley R.
Published: February 2019

A series of experiments were initiated to evaluate the influence of notching on improving lateral branching of young apple trees. Buds on 2-year-old wood of `Redspur' Delicious/MM.111 were notched at 2-week intervals from 6 weeks before bloom to 2 weeks after. Notching increased lateral branching cubically with the greatest response occurring when notching was done 2 to 4 weeks before bloom. Bud break occurred equally well and shoots grew comparably when `Redcort'/M.7 were notched at the tip, middle, or base. Bud break and shoot growth from unnotched buds was greatest at the tip, intermediate in the middle and least at the base. Limbs of `Spygold'/M.7 were spread to a 45 degree angle then one bud from each l-year-old shoot was notched at either the top, side or on the bottom of the shoot. Notching increased lateral branching from all bud positions, but the greatest response was from buds notched at the top and least from those located at the bottom of a branch. Buds of `Marshall McIntosh' were notched on either 1 or 2-year-old wood. Notching increased lateral branching more on 2-year than on 1-year old wood.
USING LOTUS 123 TO INTERCONVERT ILLUMINANCE, IRRADIANCE, AND PHOTON FLUX DENSITY VALUES
Authors: Wright Daniel C.
Published: February 2019

Because ASHS has adopted in their editorial policies the use of Systeme International (SI) units, it has become necessary to report light measurements in units other than footcandles. Since measurements using a radiometer can be tedious, tables providing values for different sources of light are often used to approximate required units. Using the tables provided by Thimijan and Heins [HortScience 18(6): 818-822], a Lotus 123 worksheet program was designed to interconvert photometric, radiometric, and quantum light units of measure. The worksheet is menu driven and can handle straight conversions or mixed conversions by entering requested information. Setup of the worksheet and instructions in its use will be provided at the meeting.
FIELD PERFORMANCE OF BIO-PRIMING FOR PROTECTION OF sh2 SWEET CORN FROM PREEMERGENCE DAMPING-OFF CAUSED BY PYTHIUM ULTIMUM.
Authors: Callan Nancy W. , Miller James B. , Mathre Don E.
Published: February 2019

Shrunken-2 supersweet (sh2) sweet corn is susceptible to preemergence damping-off caused by Pythium ultimum, especially when planted into cold soil. Bio-priming, a seed treatment which combines the establishment of a bioprotectant on the seed with preplant seed hydration, was developed to protect seeds from damping-off.

In a series of field experiments conducted in Montana's Bitterroot and Gallatin Valleys, bio-priming or seed bacterization with Pseudomonas fluorescens AB254 protected sweet corn from P. ultimum damping-off. Bio-priming corn seed with P. fluorescens AB254 was comparable to treatment with the fungicide metalaxyl in increasing seedling emergence. Seedlings from bio-primed seeds emerged from the soil more rapidly than from nontreated seeds and were larger at three weeks postplanting. Seeds of sh 2 and sugary enhancer (se) sweet corn, as well as that of several sh 2 cultivars, were protected from damping-off by bio-priming.
A HYPERCARD APPLICATION FOR THE SELECTION OF SOUTHERN LANDSCAPE PLANTS
Authors: Taylor Karen H. S. , Cobb Dr. Greg , Zajicek Dr. Jayne
Published: February 2019

Designing a landscape involves the selection of plants with certain characteristics such as height, color, hardiness zone, bloom time, etc. A Hypercard stack, which is a specific type of software application for Macintosh computers, was developed to aid landscapers in the location of plants with the desired characteristics. This Hypercard stack, called the “Plant Stack”, is based on the book, Identification Selection and Use of Southern Plants for Landscape Design, by Dr. Neil Odenwald and James Turner. The stack is also useful as an educational tool; for example, it can be used as a set of flash cards. Use of the software for selecting southern plants will be discussed as will use of the same software as an educational tool.
INFLUENCE OF TRICHODERMA ON THE GROWTH OF BEDDING PLANTS
Authors: Jeong GyeSoon , Brown John M. , Jeong Byoung Ryong
Published: February 2019

Trichoderm a spp. are currently being investigated for biological control of soil-borne pathogens and their potential to enhance plant growth and development. The influence of T. harzianum and T. hamatum on growth of 7 bedding plant species was Investigated. Trichoderm a formulated in peat moss and wheat bran, was mixed into germination and growing media at 1 × 106 cfu per gram of medium. Seeds were germinated in plugs and later grown in cellpacks containing a treated and non-treated medium until market stage. Plants were evaluated by measuring height, fresh and dry weight, and number and timing of flowering. Growth enhancement was found in marigold (14.8% dw), petunia (15.5% dw) and tomato (38.2% dw), however, no significant differences were seen in celosia, impatiens, salvi a and vinca. Results suggest that growth enhancement by Trichoderm a is species dependent and that Trichoderm a applied in the plug mix remains-effective through marketing stage.
REGENERATION OF CITRUS VIA SHOOT APECIES
Authors: Rogers Suzanne M.D. , Dias Kalyani , Byrne David
Published: February 2019

Viral damage is a major problem in citrus. As most citrus are asexually propagated, it is necessary to have an alternative way of regenerating virus-free plants from infected plants. Shoot apicies are the most suitable explant material for this purpose because that part of the plant is virus-free. Fifty sour orange shoot tips and 22 Swingle shoot tips, 1 mm - 1.5 mm long, were excised from in vitro germinated seedlings and cultured on semisolid Murashige and Skoog medium, without growth regulators, containing 0.2 % Gelrite. After 8-10 weeks, shoots and leaves developed in 68'% of the sour orange explants, and in 77% of the Swingle explants. Some explants produced roots, after 11-12 weeks, and could be removed from culture and established in soil medium.
HOME USE OF LAWN AND GARDEN CHEMICALS AND THE POTENTIAL FOR GROUND WATER CONTAMINATION
Authors: Halstead John M. , Kerns Walden R. , Relf P. Diane
Published: February 2019

Public concern over the impacts of pesticides and fertilizers on ground water quality has been increasing. Health impacts from ingestion of these chemicals in ground water vary considerably. Recent estimates of the volume of pesticides used in the U.S. indicate that home and garden uses account for about six to eight percent of total pesticides used. To obtain information on types and application rates of home garden chemical use, a telephone survey of Virginia homeowners was undertaken in the summer of 1988. Information was obtained on: 1) size of respondents' lawns and gardens; 2) use of a professional service to manage the lawn or garden, 3) what chemicals were applied and frequency; 4) sources of information used in making chemical use decisions; 5) use of product label instructions and difficulty in interpreting instructions; and 6) perceived threat to water quality, human health, or ground water from properly used home and garden chemicals.
EFFECTS OF CHRONIC SHADE AND FOLIAR NUTRIENT SPRAYS ON APPLE SPUR VIGOR AND PERFORMANCE
Authors: Robinson Terence L. , Ren Zhongbo
Published: February 2019

Eleven year-old Empire/M.7 apple trees were shaded continously for 4 years with half-tree shading cages. Shading reduced primary spur leaf duration, bourse shoot leaf area, specific leaf weight, spur diameter and bud diameter. Over the four years, shaded spurs continued to increase in length but spur diameter increased very little resulting in long and brittle spurs. However, shaded spurs continued to flower and set fruit. Leaf area development was similar inside and outside the cages at one week after bloom but by 2 weeks after bloom, spurs inside the cages had significantly lower leaf area. Shading reduced fruit set, fruit size, fruit color, fruit soluble solids and fruit dry matter. Fruit growth rate was reduced by shading early in the season but was no different than the unshaded controls by 4 weeks after full bloom.

In an attempt to reverse the negative effects of shading on spur vigor, foliar urea, zinc-EDTA and solubor were sprayed 3 times during the early growing season each year. Rather than increasing spur leaf area, foliar nutrient sprays significantly reduced bourse shoot leaf area and did not increase the duration of primary spur leaves. Although foliar nutrients reduced total spur leaf area, they improved fruit size, color and soluble solids slightly.
NEW SPECIALTY CROPS FOR HOME AND MARKET GARDENS
Authors: Newenhouse Astrid , Harrison Helen
Published: February 2019

The primary goal of this project is to introduce various citizenry groups within Wisconsin to new and potentially profitable alternative crops and production systems, and to acquaint them with crops and ornamental which may be common in Europe and Asia but which have not been extensively grown in our region. Approximately 50 new cultivars of gourmet vegetables, edible flowers, everlasting flowers, fresh cut flowers, and ornamental grasses were field tested 3 years for their adaptability for home and market gardens in Wisconsin. Cultivars were chosen for their unique flavor, color, shape, or texture. Greenhouse grown plants were transplanted onto black plastic mulch, with an annual rye–grass living mulch planted between crop rows. Aside from carbaryl and Bacillus thuringiensis used for cole crop insect control, no chemical pesticides or herbicides were used. Data taken includes notes on production, climate adaptability, disease and insect stress, maturation date, color, taste, and texture. Regional interest has been widespread from various groups including growers for gourmet restaurants, farmers market producers, garden clubs, youth organizations, and urban gardeners..
A FEASIBILITY STUDY ON A STATEWIDE YARDWASTE COMPORTING PROGRAM FOR VIRGINIA
Authors: May James H. , Relf P. Diane , Simpson Thomas
Published: February 2019

The Commonwealth of Virginia has mandated a recycling goal of 10% of municipal solid waste (MSW) by 1991, 15% by 1993, and 25% by 1995. Yardwaste (leaves, grass clippings, shrub and tree prunings) comprises 15% to 20% of MSW going to landfills daily. Yardwaste can be recycled by collecting material, piling it into large windrows, and allowing it to decompose by comporting. The finished product can be used as a soil amendment by nurseries, landscapers, farmers, local/state government projects, and homeowners.

The Virginia Co-op. Ext. Service at VPI&SU was authorized to perform a feasibility study on implementing a statewide yardwaste comporting program. The methods included a literature review, site visits in other states to assess technologies, and surveys to determine potential uses and users of composted yardwaste in Virginia.

The study was presented to the Virginia Dept. of Waste Mgmt. in November 1989, and as House Document No. 34 to the Virginia General Assembly. Three bills and one joint resolution are pending.
SPATIAL AND TEMPORAL TEMPERATURE VARIATION IN A GREENHOUSE
Authors: Rose Mark A. , White John W.
Published: February 2019

Temperature affects all major plant physiological processes. Traditional methods of controlling greenhouse temperatures use aerial sensors that do not monitor temperatures within each component of the soil-plant-atmosphere continuum.

Bench, pot, plant canopy, and aerial temperatures were monitored using thermocouples and thermistors processed by environmental computers during a wide range of greenhouse conditions. These include diurnal cycles of high and low solar radiation, night periods with and without artificial lighting, and various ventilation and heating conditions. Spatial temperature gradients of 10-22 °C were discovered during both day and night conditions. These spatial variations cause significant differences in average temperatures between and within benches over diurnal and even seasonal cycles.

Preliminary surveys of microclimatic variations that occur within the greenhouse experimental area are essential for choosing the proper experimental design. Continuous environmental monitoring during the experiment is necessary for interpreting experimental results.
SOURCES OF PLANT HUMOR FOR USE IN HORTICULTURAL EDUCATION
Authors: Hershey David R.
Published: February 2019

Research indicates that humor is an effective method to reinforce learning, yet humor is rarely used in horticultural textbooks. Use of humor in horticulture is easier than in many disciplines because humor dealing with plants is less likely to offend specific population segments since plants, not people, are usually the butt of the jokes. A large collection of plant humor has been assembled, including the following: Edward Lear's 32 line drawings of “Nonsense Botany”, e.g. Manypeeplia upsidonia; Gary Larson's macabre Far Side cartoons dealing with plants, e.g. the “Venus kidtrap”; periodic tables of vegetables and of fruits & nuts; Arcimboldo's Renaissance paintings of faces composed of flowers, vegetables, and plant parts and their modern imitations; Robert Wood's book, How to Tell the Birds From The Flowers, containing drawings and poems; Axel Erlandson's fantasticly grafted trees; plant movies like the two versions of Little Shop of Horrors, which is set in a flower shop; Joke Fountains of the Renaissance; and numerous cartoons from science periodicals.
A RAPID TEST FOR DETERMINING SEED VIGOR IN RED OAK
Authors: Cooper Chris , Struve Daniel , Bennett Mark
Published: February 2019

Previous experiments showed that a 10 day aerated water soak (water priming) increased red oak (Quercus rubra) seed vigor. After water priming most seed had split pericarps. Seed with split pericarps were observed to be more visorous than water primed seed without split pericarps. An experiment was conducted to determine if pericarp splitting could be used as an indicator of red oak seed vigor. The following experiment was conducted. Red oak seed from three open pollinated, half-sib families, were water primed for 10 days. Seed were separated into two groups, seed with split pericarps and without split pericarps, and a germination test conducted. Unprimed seed were used as a control. There were significant differences among the families in seed vigor (germination completeness, uniformity and speed). Primed seed with intact pericarps had lower seed vigor than primed seed with split pericarps and unprimed seed. The results suggest that pericarp splitting following water priming is an indicator of high seed vigor.
EVALUATION OF AN IRON-STRESS RESPONSE FOR PIN OAK AND RED OAK SEEDLINGS GROWING IN A STATIC SOLUTION CULTURE SYSTEM
Authors: Rees Cameron , Robbins James
Published: February 2019

The iron-efficiency of pin oak (Quercus palustris) and red oak (Quercus rubra) grown in a static solution culture system was evaluated. Treatments included nutrient solutions with no iron, an unavailable iron form (Fe2 O3), and an available iron form (FeEDDHA), each adjusted to a starting pH of 5.5 or 7.0. Both oaks grew better when the available form of iron was used than when the solution contained unavailable or no iron. There was no difference in the height or leaf color for plants of either species when grown with unavailable or no iron. Red oak grown with an available iron form significantly lowered the pH of the solution prior to a growth flush. A similar drop in solution pH was not observed for pin oak growing under similar conditions.
PHOTOPERIODIC REGULATION OF VEGETATIVE GROWTH AND GIBBERELLIN METABOLISM IN STRAWBERRY
Authors: Early Jack D. , Martin George C.
Published: February 2019

Photoperiod is an important environmental signal for regulating developmental patterns in many plant species. In several species, photoperiodic regulation of gibberellin A1 biosynthesis has been implicated as the mechanism by which photoperiod may alter development. To examine this phenomenon in strawberry, Fragaria virginiana plants grown under long day (LD) and short day (SD) conditions with equivalent total PAR were examined to determine changes in vegetative growth and GA1 biosynthesis.

LD conditions (16 hr) promoted vegetative growth. Runner production, total leaf area, area of individual leaves, and petiole lengths, all increased under LD conditions. No runner production occurred under SD conditions (8 hr); however, the number of branch crowns increased.

Gibberellins A44, A19, A20, and A1, all from the GA1 biosynthetic pathway, were identified in plants under both LD and SD conditions. However, SD conditions appeared to affect the 2β-hydroxylation of GA20 to GA1. Whereas levels of most GAs decreased under SD conditions, levels of GA20 increased, and only trace amounts of GA1 were found, indicating a possible blockage of the pathway at this point. As GA1 is considered the active component of the pathway, blockage of GA20 conversion under SD conditions may explain the concomitant reduction in vegetative growth.
FIELD RESPONSE OF MICROPROPAGATED CRANBERRY
Authors: Zeldin Eric L. , McCown Brent H. , Stang Elden , Klueh John
Published: February 2019

A project to determine the comparative growth response of micropropagated (MP) and field propagated (FP) cranberry plants was conducted in field plots at a commercial cranberry marsh. Microcuttings were derived from shoot culture and rooted in either plugs or peat pots filled with peat. Replicated 1 m2 plots of MP plants and 15 cm FP cuttings were planted in June. Survival of MP plants after one month was significantly greater than that of the FP plants. Significant growth differences were observed later in the season. The MP plants produced more branches and greater runner elongation, resulting in a much greater ground cover. Many of the FP plants flowered and produced fruit, while the MP plants produced neither. Far fewer new flower buds were set in the fall on the MP plants. Potential advantages of MP cranberries include the fast, uniform establishment of new marshes and consequently earlier achievement of full productivity, and the rapid introduction of new genotypes from breeding or genetic engineering.
ROOT CO2 EFFECTS ON THE PEACH ROOT SYSTEM
Authors: Glenn D. M. , Welker W. V.
Published: February 2019

Carbon dioxide is produced by microbial and plant respiration and accumulates in the soil. In previous field studies, CO2 levels were higher under a killed sod soil management system, relative to cultivation and herbicide systems (1.8 vs 0.8 and 1.0%), respectively. Our objective in these studies was to measure the effect of elevated levels of root system CO2 on root and shoot growth and nutrient uptake. Using soil and hydroponic systems in greenhouse studies, we maintained root system CO2 levels between 1.5 and 2.5%. Control CO2 levels were less than 1%. Root length density and dry matter partitioning to the root system were increased by root CO2 in soil and hydroponic studies; shoot growth was unaffected. In hydroponic culture, root CO2 increased P uptake, solution pH, root volume and the number of lateral roots/cm root axis. Elevated levels of CO2 in the root system stimulated root growth in both the soil and hydroponic studies.