bluuebunny/crossref_metadata_2025 huggingface dataset:
746 PB 102 DIFFERENCES IN SUCROSE METABOLISM RELATIVE TO ACCUMULATION OF BIRD-DETERRENT SUCROSE LEVELS IN FRUIT OF VACCINIUM SPECIES
Authors: Darnell R.L. , Cano-Medrano R. , Koch K.E.
Published: February 2019

Variability in sucrose levels and metabolism in ripe fruit of several Vaccinium species were examined. The objective was to determine if sufficient variability for fruit sucrose accumulation was present in existing populations to warrant attempts to breed for high-sucrose fruit, which potentially would be less subject to bird predation. Three-fold differences in fruit sucrose concentration were found among species, ranging from 19 to 24 mg·(g fw)-1 in V. stamineum and V. arboreum to about 7 mg·(g fw)-1 in cultivated blueberry (V. ashei and V. corymbosum) and V. darrowi. Soluble acid invertase activity was negatively correlated with fruit sucrose concentration. There was no apparent correlation between fruit sugar concentration and either sucrose phosphate synthase or sucrose synthase activities, both of which were low for all species studied. The degree of variability in fruit sucrose accumulation among Vaccinium species supports the feasibility of developing high sucrose fruit, which would be a potentially valuable addition to current strategies of minimizing crop losses to birds.
748 PB 108 THE RELATIONSHIP BETWEEN ROOT HAIR DEVELOPMENT AND OTHER ROOT ATTRIBUTES IN CITRUS AND CITRUS RELATIVES
Authors: Crawford Richard J. , Eissenstat David M.
Published: February 2019

The relationship of genotypic variation in root hair development with root proliferation, mycorrhizal colonization, and specific root length (length / dry mass) was studied in sixteen field-grown citrus relatives. The species varied widely in hair development, root length and mass density, and specific root length. No correlation was found between hair development, mycorrhizal colonization, root proliferation, and specific root length. However, there was a significant correlation (r=.55) between the percentage of total root length with hairs and the percentage of hairs with adhered soil. In a second experiment, the phenotypic plasticity in root hair development was studied in four-citrus rootstooks: Swingle citsumelo, Sour orange, Trifoliate orange and Volkamer lemon. Roots were grow” in either mineral soil or high organic matter media. After eight weeks, root length density and percentage of root length with hairs averaged over all four rootstocks was 232 % and 85 % greater in the organic media than in the mineral soil. Similar to the first experiment the percentage of total root length with hairs was significantly correlated (r=.99) with the percentage of hairs with adhered soil.
752 PB 120 TRANSPORT OF TRYPTOPHAN AND CONVERSION TO IAA IN AVOCADO TISSUES
Authors: Bertline Isa , Lovatt Carol J.
Published: February 2019

Tryptophan is known to be a precursor of IAA in plants. The amount of IAA available for the development of avocado fruit might be a limiting factor for its growth. It is well known that IAA is not transported into developing fruit along its strictly basipetal transport route. Therefore, IAA present in fruit must be synthesized in situ. We investigated the possibility that tryptophan or its metabolites are transported from leaf to fruit.

An HPLC method was developed to quantitatively isolate and measure tryptophan and all well known intermediates in the synthesis of IAA. Avocado leaves were fed L-[side chain-3-14C] tryptophan and its transport and metabolism to IAA within the leaf and within the fruit were monitored over time. Significant movement of tryptophan or a metabolite from leaf to fruit occurs in 24 h.
755 PB 149 IN VIV0 POLLEN GERMINATION AND TUBE ELONGATION ON FEMALE FLOWERS IN `SHAHANI' DATE PLAM
Authors: Tavakkoli Asad , Tafazoli Enayat
Published: February 2019

Hand pollinated pistilate date palm flowers were removed 2, 6, 10, 16, 20 hours after pollination, fixed. cleared with 8N NaOH and stained with aniline blue. The Fluoresced pollen tubes were abserved under ultra violet microscope. It was noted that under natural conditions with mean temperature of 19C pollen tube reached the ovary after 16 hours.

Viability test of fresh and stored pollen grains using Brewbaker & Kwack's media at room temperature was 85 and 52.5%. respectively.
759 PB 181 WATER AND HORMONAL INVOLVEMENT IN GROWTH AND DEVELOPMENT OF PEACH TREES UNDER ROOT RESTRICTION
Authors: Alvarez Leonardo , Beyl Caula A.
Published: February 2019

A greenhouse study was established to evaluate the effect of different levels of root restriction on morphology, hydraulic conductivity, root length, and t-zeatin and dihydrozeatin riboside levels in exudate in peach trees. One-year-old `Redhaven' peach on `Lovell' rootstock were grown for 18 weeks in containers with volumes ranging from 1.93 to 11.55 liters. Plants grown in the most restricted containers (1.93 to 3.85 L) had roots that were smaller and exhibited fewer primary and secondary branches with less average length. Final leaf, stem, root fresh and dry weight and root length were reduced in the highly restricted versus the less restricted treatments (7.7 and 11.55 L). Root hydraulic conductivity (Lp) was not affected by container volume. There was less dihydrozeatin riboside and trans-zeatin in exudate of the most restricted plants versus the less restricted ones. Cytokinin levels continued to decrease over the time course of treatment. Shootroot ratio was not altered by the container volume suggesting a coordination of root and shoot growth modulated by the container size.
762 PB 190 RELATIONSHIP OF PHENYLALANINE AMMONIA LYASE AND ANTHOCYANIN SYNTHESIS IN APPLE
Authors: Ju Zhiguo
Published: February 2019

Three years of experiments were carried out with both Delicious fruit on trees and fruit skin discs. There were two peaks of phenylalanine ammonia lyase (PAL) activity during fruit development. One occurred in the fruitlet stage and the other in the fruit enlargement stage. The first peak was coincident with anthocyanin synthesis in fruitlet but the second peak did not correlate with pigment formation during maturation. In fact, PAL activity decreased gradually during fruit maturation and coloration. Treatment with L-α-aminooxy-B-phenylpropionic acid, a specific PAL inhibitor, decreased PAL activity in fruit and in skin discs 57% and 80%, respectively, but did not change anthocyanin content. Cycloheximide inhibited anthocyanin synthesis by 76% in fruit and 85% in skin discs, but did not significantly inhibit PAL activity. On the other hand, PAL activity was positively correlated with concentrations of simple phenols which were direct products of PAL and precursors for synthesis of lignin, anthocyanin and other flavonoid.
764 PB 310 GROwTH AND FLOWERING OF HEUCHERA CULTIVARS
Authors: Albrecht M. L. , Crockett D. M.
Published: February 2019

Heuchera cultivars were studied to examine the influence of photoperiod and refrigerated storage on vegetative and reproductive growth. As daylength increased from 9 to 15 hours, using day extension, petiole length and leaf area increased. Daylength during the forcing period appears to have minimal influence on reproductive growth. Forcing under 15-m daylength reduced the time to inflorescence emergence and delayed the time to anthesis of first floret and inflorescence maturity in comparison to natural daylengths or short days. Cold storage (4°C) for 14 weeks resulted in quicker inflorescence emergence than no storage or 10 weeks of storage.
766 PB 316 INFLUENCE OF PHOTOPERIOD AND LIGHT INTENSITY ON PLANT HEIGHT OF LILIUM LONGIFLORUM THUNB
Authors: Blom Theo J. , Tsujita M.J. , Roberts Glen L.
Published: February 2019

Potted plants of Lilium longiflorum Thunb. cvs. `Ace' and `Nellie White' were grown either under an ambient photoperiod (APP) or under an 8-hour photoperiod (8PP) in a greenhouse. The latter photoperiod was achieved by pulling black cloth over the plants at 1615HR and removing the cloth at 0615HR each day, from emergence to flowering. Within each photoperiod, ambient light intensity was reduced by 0, 20, 40 or 60% using various shade cloths permanently suspended above the plants. Heating was set at 20/16C for the dark/light period, respectively. Plant height, determined from the rim of pot to the top of plant, was 25% lower under 8PP compared to APP for both cultivars. Plant height of `Ace' and `Nellie White' increased by 1.5 mm and 2.5 mm, respectively, per 1% light reduction.
767 PB 319 CONTROL OF CYCLAMEN DEVELOPMENT BY IRRADIANCE AND TEMPERATURE
Authors: Karlsson Meriam G. , Hanscom Jan T.
Published: February 2019

Seeds of cyclamen `Laser Scarlet' were germinated at 20C in darkness. Four weeks after germination, the seedlings were moved to a greenhouse at 20C and 16 hours daylength and 4 weeks later transplanted into 10 cm (520 cm3) pots. Plants were grown under 8 or 16 hours daylength in combination with 3.0, 7.5 or 12.0 mol·day-1m-2 for 9 weeks after transplant. The instantaneous irradiance was adjusted based on photoperiod to provide the desired total daily irradiance levels. After the 9 weeks photoperiod and irradiance treatment, plants were allowed to develop and flower at 16 hours daylength, 7.5 mol·day-1m-2 (130 μmol·s-1m-2) and 15C. There was a trend for an increased number of leaves for cyclamen grown at higher total daily irradiance levels at either 8 or 16 hours photoperiod. The largest number of leaves (14 ± 2.2 leaves) after the 9 weeks was observed for cyclamens grown at 16 hours photoperiod and 12 mol·day-1m-2 (210 μmol·s-1m-2). The plants grown at the longer day length and highest irradiance level also, accumulated most dry weight (92 ± 18.7 mg) during the 9 weeks of photoperiod and it-radiance treatment.
776 PB 386 THE INFLUENCE OF FOUR COMMERCIAL GROWTH RETARDANTS ON THE GROWTH AND DEVELOPMENT FLOWERING CABBAGE AND KALE CULTIVARS
Authors: Carter Johnny , Mahotiere Sauveur
Published: February 2019

During the Fall of 1993, four commercial growth retardants (B-nine, Cycocel, A-rest and Bonzi) were compared for their effectiveness in controlling the growth and development of three ornamental cabbage cultivars (white, red and pink) and two flowering ornamental kale cultivars (frizzy red and red peacock). Two weeks after transplanting; seedling of each cultivar were sprayed with aqueous solutions of the four commercial growth retardants. Treatments for each cultivar were arranged in a randomized complete block design with 6 replications. Plant height, plant width and dry weight were the parameters used to measure growth and development. Results showed that all the growth retardants except for cycocel significantly affected growth and development without any effect on head formation and color development. Bonzi caused the greatest growth suppression.
EFFECTIVENESS OF PACLOBUTRAZOL ON HEIGHT CONTROL OF MINI-POINSETTIAS
Authors: Whipker Brian , Hammer P. Allen
Published: February 2019

Mini-poinsettias are a popular form of potted plant, but there is a need to control plant height because tall growing cultivars are used. A study was conducted to determine the suitability of paclobutrazol to control height of mini-poinsettias. Cuttings of poinsettia cultivars Freedom and Red Sails were taken on 10 Sept. 1993 and rooted under mist. On 11 Oct. when short days began, plant height was measured and 4 plant growth regulator (PGR) treatments were applied as foliar sprays using a volume of 204 ml·m-2: paclobutrazol at 15, 30, 45 and 60 mg·liter-1, plus an untreated control. At anthesis, plant height (pot rim to top of plant) and bract diameter (measured in 2 directions and averaged) were measured. Data for plant height gain (PHG), the difference between plant height at anthesis and when PGRs were applied, and bract diameter were analyzed statistically.

PHG was significantly different at the cultivar × treatment interaction. For `Red Sails' all paclobutrazol treatments significantly retarded PHG, but there were no significant differences in PHG with increased rates of application. For `Freedom' only paclobuuazol rates at 30 and 45 mg·liter-1 significantly retarded PHG. Bract diameter was significantly different at paclobunazol rates 30 mg·liter-1 or greater, with diameter decreasing as the rate of PGR applied increased
779 PB 395 PULSING TEMPERATURES AND SYRINGING AT SUNRISE REDUCE STEM ELONGATION OF EASTER LILY
Authors: Faust James E. , Verlinden Sven , Heins Royal D.
Published: February 2019

Rapid reduction in temperature for two to three hours starting at sunrise reduces stem elongation compared to elongation of plants maintained under constant temperatures during the day. This experiment was designed to determine if syringing plants with water at sunrise would substitute for a reduction in air temperature or enhance the response to the drop in temperature. Easter lily (Lilium longiflorum Thumb.) plants were exposed to constant 20°C or to 20°C and then 16°C for a 3-hr period following sunrise. Half the plants in each temperature regime were syringed at 30-minute intervals with 20°C water for 3 hr starting 20 minutes before sunrise. Shoot-tip temperature during the three-hr pulse time averaged 20.0 and 17.3°C for the dry plants and 17.3 and 14.7°C for the syringed plants. Total elongation for the dry plants at 20°C was 30 cm and for the temperature-pulsed plants, 4.8 cm less; for the syringed plants, 3.3 and 5.8 cm less, respectively. While shoot-tip temperature of dry plants averaged 0.9°C above air temperature during the remaining hours of the day, syringed plants averaged 1.0°C cooler than the same air temperature even though plants had dried. The data indicate the reduction in stem elongation from a low-temperature pulse at sunrise can be enhanced by evaporative cooling.
784 PB 430 NONCONTACT GROWTH ANALYSIS USING 3-D IMAGE PROCESSING
Authors: Shimizu Hiroshi , Heins Royal D.
Published: February 2019

A computer vision system for noncontact growth analysis was developed. Front and side images of a plant were captured simultaneously using a mirror system and CCD camera and were magnetically stored on a magneto-optical disk. Images acquired at night were obtained by irradiating plants with incandescent light filtered to wavelengths of 850 nm and greater. Images were automatically captured and saved every 12 minutes. After images were collected, outlines of plant shape were extracted from stored images, a three-dimensional center line of the plant was extracted from the outline, and the elongation rate was computed. The outline extraction algorithm was modified to improve spatial resolution of images, and the thinning algorithm created a representative line of the plant by calculating a center line of the stem so the three-dimensional length could be calculated. Results of growth analysis on Verbena bonariensis L. plants grown under three photoperiods (8, 12, and 16 hours) and three day/night air-temperature combinations (15/25, 20/20, and 25/15) will be presented.
785 PB 433 VALIDATION OF A ROSE SHOOT DEVELOPMENTAL MODEL
Authors: Pasian C.C. , Lieth H.J.
Published: February 2019

Temperature effects on the rate of flowering rose shoot development were previously modeled using a thermal units (heat units) approach. The current objective was to validate this model for three rose cultivars and to determine its suitability for use in rose production. Flowering shoots of `Cara Mia', `Royalty', and `Sonia' plants, grown in greenhouses at three temperature settings, were observed daily to determine when each of the following developmental events occurred: “harvest”, “bud break”, “unfolding of each leaf”, “visible flower bud”, and “shoot ready for harvest”. Each stage was defined to facilitate accurate, repeatable observations. Average hourly air temperatures were used in computing the accumulated thermal units (TU) required for shoots to develop from from one stage to the next. The base temperature (used in the TU computation) did not differ significantly among the cultivars; the value of 5.2C was used. Using these to predict the days on which the shoot was ready for harvest resulted in ±2 day accuracy for most shoots of `Royalty' and `Sonia' and ±2.5 days accuracy for most `Cara Mia' shoots. This indicates that this method is suitable for timing of rose crops and deciding on temperature set-points.
790 PB 030 EVAPORATIVE COOLING AND PRUNING DATE AFFECT REST DEPTH AND BREAK OF PRIMARY BUDS IN `FLAME SEEDLESS' GRAPEVINES
Authors: Osorio-Acosta Guadalupe , Siller-Cepeda Jorge
Published: February 2019

Table grapes growing under desert conditions present a short and shallow rest mainly due to low chilling and high daily temperatures. Results using Evaporative Cooling (EC) have shown that rest is modified, and the opening of primary buds and number of clusters per plant depended on pruning date and cyanamide rate. From Oct 26 until Dec 30, rest depth was assessed under lab conditions on `Flame Seedless' canes from EC-treated and control vines. We found that rest depth was shallow and final budbreak was higher in EC-treated plants at all sampling dates. However, hydrogen cyanamide treated canes under both conditions showed no difference on final budbreak, although the opening of primary buds was higher on the EC-treated plants. Field trials were established to quantify the effect of pruning date associated with those treatments (EC and Control) on the number of clusters per plant. Plants were pruned on Dec 14, Dec 22, and Dec 30, and cyanamide (5% Dormex) was applied immediately. Plants under EC conditions and pruned on the earliest dates enhanced the number of cluster per vine by 40 and 21.7% respectively, as compared with control plants.
796 PB 068 STOMATAL FUNCTION OF IN VITRO GRAPE PLANTLETS TREATED WITH AND WITHOUT POLYETHYLENE GLYCOL
Authors: Ali-Abmad Masooma , Hughes Harrison
Published: February 2019

Scanning electron microscopy was used to study stomatal function of grape (Vitis sp. `Valiant') plantlets grown in vitro, polyethylene glycoltreated (PEG) in vitro and greenhouse. Fully open stomata were observed in in vitro grown plants with large aperture (13.5μm) as compared to narrow stomatal opening and small aperture in PEG-treated (4.9pm) and greenhouse grown plants (3.2μm). Furthermore, stomates of persistent leaves initiated during in vitro culture remained fully open with large apertures (12.8μm) two weeks after transplanting in the greenhouse. In contrast, newly-formed leaves produced in the greenhouse from in vitro cultured plants showed narrow stomatal opening with small apertures (3.3μm). In vitro produced leaves exhibited rapid wilting followed by irreversible tissue damage and severe desiccation within three hours of transplantation into the greenhouse. However, PEG-treated plantlets showed a reduced stomatal opening with associated minimal stress when directly transferred into the greenhouse. Thus use of an osmotic agent, PEG, induced more normal stomata1 function as well as improved survival after transfer to the greenhouse.
798 PB 074 CHANGES IN WEED SPECIES WITH DIFFERENT COVER CROPS IN TWO CALIFORNIA VINEYARDS
Authors: Elmore Clyde L. , Steinmaus Scott , Donaldson Dean
Published: February 2019

Cover crops are grown in vineyards for many reasons, including erosion control, maintaining organic matter and changing pest complexes. Changing a management practice from using resident vegetation as a cover to other planted cover crops will change the vineyard floor flora. The cover crops of `Olge' oat, `Olge' oat and purple vetch, and purple vetch alone were compared to resident vegetation as winter planted cover crops. The cover was harvested in April of each year and blown under the vine row; The cover crop remains were disked into the middles after mulching. Three varieties of subterranean clover were planted in the vine rows at each location in one-half of each of the cover crops. The winter annual weed species, black and wild mustard, common chickweed and annual bluegrass decreased in the inter-row areas. The perennial weed field bindweed increased in all cover crop treatments.
799 PB 077 SUSCEPTIBILITY OF AMERICAN, EUROPEAN, AND INTERSPECIFIC HYBRID GRAPE CULTIVARS TO THE FUNGUS SEPTORIA AMPELINA
Authors: Mitchell James K. , Ford Robert H. , Patterson W. Keith
Published: February 2019

European Vitis vinifera L. (four cultivars); interspecific hybrid (seven cultivars); and American V. aestivalis Michx. (one cultivar), V. labrusca L. (three cultivars), and V. rotundifolia Michx. (two cultivars) grapevines were tested for susceptibility to Septoria leaf spot disease. V. rotundifolia cultivars Cowart and Fry exhibited hypersensitive-type resistance. All other American, European, and hybrid cultivars tested were susceptible with varying levels of disease severity. Cultivars with little (e.g. interspecific hybrid) or no (e.g. European) V. labrusca L. heritage were more susceptible to Septoria leaf spot than American V. labrusca cultivars.
804 PB 112 INFLUENCE OF CULTURE CONTAINER ON IN VITRO SHOOT PRODUCTION AND CALLUS FORMATION OF MUSCADINE GRAPE
Authors: Robacker Carol D.
Published: February 2019

Nodes from in vitro grown shoots of `Regale' and `Triumph muscadine grape (Vitis rotundifolia) were cultured in 25 × 95-mm glass vials, 25 × 150-mm glass culture tubes, 55 × 70-mm glass baby food jars and 100 × 25-mm plastic petri dishes. Culture medium consisted of Murashige and Skoog salts and vitamins, 80 mg/l adenine sulphate, 170 mg/l sodium phosphate, 2 mg/l BA and 8 g/l agar. Amount of medium dispensed was 8 ml per vial, 18 ml per culture tube and jar, and 70 ml per petri dish. Containers were covered with clear plastic lids, sealed with parafilm, and placed under fluorescent lights for six weeks. The number of shoots per explant that formed in petri dishes was three to four times greater than those formed on explants in vials, tubes and jars. However, the number of nodes per shoot were fewer in dishes than in the other containers. Callus formation was excessive in jars to the detriment of shoot production. Vials and tubes had small amounts of callus, while little or no callus was observed in dishes.
807 PB 141 LEAF EPICUTICULAR WAX OF IN VITRO GRAPE PLANTLETS TREATED WITH AND WITHOUT POLYETHYLENE GLYCOL
Authors: Ali-Ahmad Masooma , Hughes Harrison
Published: February 2019

Scanning electron microscopic (SEM) studies and gravimetric analysis of in vitro cultured leaf surfaces showed reduced epicuticular wax (EW) structurally and quantitatively as compared to greenhouse plants. However, leaves of in vitro plantlets subjected to polyethylene glycol-treatment (PEG) showed an increase in quantitative and structural EW which was similar to that of greenhouse plants. Furthermore, leaves initiated during in vitro culture and which persisted, when transferred to the greenhouse, showed an increase in structural wax as well as in amount, 30 days after transplanting in the greenhouse. Similarly, leaves newly-formed in the greenhouse from in vitro cultured plants developed more dense crystalline structure and greater levels of wax than those leaves observed immediately after removal from culture. A correlation between density of structural EW and amount of EW were observed in in vitro cultured, PEG-treated in vitro cultured and greenhouse grown leaves.
808 PB 144 EFFECTIVNESS OF AEROSOL SPRAYS FOR CONTROLLING ROT IN TABLE GRAPES
Authors: Ahmedullah M. Ahmed
Published: February 2019

Fruit of Vitis vinifera cvs. Flame Seedless, Thompson Seedless and Black Monukka were fumigated with 4, 6 and 8 Deccodione Smoke Tables (DST) for 30 minutes. Fruit was stored at 32 F and high relative humidity. Decay control index, freshness of stems and bleaching around the capstem were recorded at 4, 8, 12 and 16 weeks of storage. Size of the aerosol particles was determined using an electrical aerosol analyzer. Fruit was analysed for Deccodione residues.

Lower rates of the fungicide gave unsatisfactory decay control. Eight DSTs successfully controlled decay upto a period of 14 weeks. There was no bleaching of pigments commonly associated with sulfur dioxide fumigation. Majority of the aerosol particles were between 0.18 and 0.32 micrometers. Deccodione residues on the fruit were within the acceptable limits established for Deccodione. There was no perceptible difference in taste between treated and control fruit. This method of decay control could provide a viable alternative to sulfur dioxide fumigation.
816 Text THE RELATIONSHIP BETWEEN CONTAINER SIZE AND TRUNK DIAMETER OF RIVER BIRCH
Authors: Milbocker Daniel C.
Published: February 2019

Trees grown entirely in containers have slim trunks. Since large tree sizes are measured interms of their trunk diameter, heavier trunks increase salable tree sizes. River Birch, Betula nigra liners were grown in containers that were increased in size at different rates determined by their trunk diameter. These measurements revealed the minimum container size necessary for unconstricted growth and measured the reduction in trunk diameter induced by smaller container sizes.
822 PB 269 PINE BARK SOIL AMENDMENTS AND NUTRITION AFFECT GROWTH AND DROUGHT TOLERANCE OF VIBURNUM PLICATUM VAR. TOMENTOSUM `MARIESII'
Authors: Wood Carleton B , Smalley Timothy J. , Rieger Mark
Published: February 2019

Container-grown Viburnum plicatum var. tomentosum `Mariesii' were planted in tilled beds and tilled beds amended with aged pine bark. After transplanting, plants were fertilized at three different rates: no fertilizer, 18.4 g of N m-2, and 36.8 g of N m-2. A 31 day drought was begun 73 days after planting. Fertilization of tilled plots induced ammonium toxicity, which caused a linear reduction in leaf area, shoot dry weight, and root dry weight. Fertilization of amended plots had no effect on shoot growth but reduced mot growth by 54%; thus, amendments ameliorated ammonium toxicity. Between 10 and 28 days after beginning the drought, plants in unfertilized-amended plots maintained higher relative leaf water contents (RLWC) and relative leaf expansion rates (RLER) than plants in unfertilized-tilled plots. Amendment induced nitrogen deficiencies contributed to the increased drought tolerance of plants from unfertilized-amended plots. Since fertilized plants developed symptoms of ammonium toxicity, we were unable to determine if increasing fertility would counteract the drought tolerance conferred by pine bark soil amendments.
823 PB 272 CAN A POROUS CERAMIC SOIL AMENDMENT LIMIT WATER STRESS OF CONTAINER-GROWN IMPATIENS `ACCENT RED'?
Authors: Triff Michael B. , Smalley Timothy J. , Rieger Mark , Radcliffe David
Published: February 2019

Isolite is a ceramic-like, porous soil amendment purported to sustain plant growth under reduced irrigation and increase plant survival during drought. The purpose of this greenhouse experiment was to determine the effect of an Isotite-amended soilless container medium on: (1) growth under reduced irrigation frequency and (2) water stress during drought of Impatiens × hybrids `Accent Red'. On 2 June 1993, seedlings were transplanted into 13.2 liter black plastic pots containing a 4:1 composted pine bark:coarse sand (vol.) medium amended with Isolite CG-1 granules at rates of 0%, 10%, 15%, and 20% (vol.). Study I. Seedlings were. irrigated with 500 ml tap water every two days for two weeks followed by a 4 week schedule of 500 ml tap water every 1, 2, 3, 4, or 5 days. In general, growth parameters were explained by irrigation treatment effects and did not differ with Isolite rate. Growth indices ranged from +54% to + 143%, while final visual quality grades ranged from 2.4 to 5.0 (5-point scale), shoot dry weight from 8.7 to 30.7 g, root dry weight from 2.0 to 7.9 g, and leaf area from 0.14 to 0.48 m2. Study II. Seedlings were irrigated with 500 ml tap water every 2 days for rive weeks followed by a two week drought. Plant water status parameters were similar at all rates of Isolite. Leaf expansion rates ranged from + 89% to +98%, white a final mid-day xylem pressure potential of -0.4 MPa and a final visual quality grade of 2.0 were uniform across all treatments. Under these conditions, Isolite did not limit water stress of container-grown Impatiens `Accent Red'.
830 PB 314 FORCING HERBACEOUS PERENNIALS TO FLOWER AFTER STORAGE OUTDOORS BENEATH A THERMOBLANKET
Authors: Iles Jeffery K. , Agnew Nancy H.
Published: February 2019

Nine herbaceous perennial species were evaluated for use as flowering pot plants for late winter and early spring sales. Plugs of Achillea `King Edward', Arabis sturii, Armeria `Alba', Bergenia `New Hybrid', Chrysogonum virginianum, Dianthus `War Bonnet', Phlox `Chattahoochee', Platycodon `Sentimental Blue', and Veronica `Sunny Border Blue' were established in 14-cm (0.8-liter) round plastic containers, grown for one season, and covered with a thermoblanket for winter. Five plants of each species were transferred to a 21 ± 3C glasshouse for forcing under natural daylength at six 10-day intervals beginning 1 Dec. 1993. By this date plants had experienced approximately four weeks of temperatures below 5C. Ambis, Chrysogonum, and Phlox, species that naturally flower in spring, were the most floriferous. Days to first flower for Arabis decreased from 30 to 26 while flower number increased 44% by the 20 Dec. forcing date. For Phlox, days to first flower decreased from 36 to 31 by 20 Dec., but flower numbers were similar regardless of forcing date. Chrysogonum averaged eight flowers throughout the study, but days to first flower increased from 25 (1 Dec.) to 31 in all following forcing dates.
834 PB 346 DEVELOPMENT OF SEED QUALITY IN RED CABBAGE
Authors: Still David W. , Bradford Kent J.
Published: February 2019

Brassica crops have an extended flowering period due to both progressive development within a given raceme and variability among multiple racemes. Early harvest can result in poor seed quality due to immaturity, while delayed harvest may sacrifice yield due to shattering. To characterize the development of seed quality, we measured maturity indices and conducted vigor tests on hybrid red cabbage (Brassica oleracea var capitata) seed harvested weekly starting 33 days after full bloom (DAF). Viability and germination rate increased from the top to the bottom of the raceme, and were maximal by 40 and 48 DAF, respectively. After 48 DAF, there was little difference in seed quality due to position on the raceme. Seed dry weight also reached a plateau by 48 DAF, when rapid dehydration began. Sensitivity of germination to inhibition by reduced water potential or abscisic acid (ABA) was assessed using a threshold model based upon germination rates. Germination became less sensitive to both factors and more uniform during maturation, with -1.0 MPa or 50 μM ABA being required to inhibit germination by 50% after about 48 DAF Seed ABA content reached a peak of 10 μg/g dry wt. by 40 DAF, then declined linearly to 1.5 μg/g dry wt. by 68 DAF Overall, optimal seed quality was attained at 54 DAF
835 PB 349 HIGH-TEMPERATURE EFFECTS ON SOLUBLE OLIGOSACCHARIDE LEVELS IN SPINACH SEEDS DURING IMBIBITION AND GERMINATION
Authors: Esensce Virgil , Leskovar Daniel I.
Published: February 2019

Spinach (Spinacia oleracea, L. cv. `Ark88-354'. `Fall Green', `Cascade') seeds of varying sensitivities to high temperatures during imbibition and germination were subjected to constant 18, 30 and 36°C for 96 hours during imbibition. Those cultivars less sensitive to high temperatures (`Ark88-354' and `Fall Green') imbibed water more rapidly at higher temperatures and had greater initial levels of raffinose and sucrose than the sensitive cultivar `Cascade'. Glucose levels were initially zero in all cultivars and increased slightly with time. Germination was more rapid at 18°C and 30°C in `Ark88-354' and `Fall Green' than with `Cascade'; the latter also failed 10 germinate at the higher temperature. Raffinose and sucrose have been implicated in membrane stabilization during desiccation and extreme low temperatures. They may serve a similar role during imbibition and germination of spinach at high temperatures, reducing secondary thermodormancy.
837 PB 355 A COMPARISON OF BROCCOLI SEED PRIMING TREATMENTS
Authors: Jett Lewis W. , Welbaum Gregory E.
Published: February 2019

Various osmotic solutions and solid carriers have been used to prime (controlled hydration followed by drying) seeds. Broccoli (Brassica oleracea L., var. italica, cvs. Brigadier and Earlidawn) seeds were primed in solutions of polyethylene glycol, potassium nitrate (KNO3), and mannitol or calcium silicate (Micro-ccl E) and vermiculite to determine which treatment provided the greatest enhancement of germination. Germination percentage and rate as well as head yield were determined in a series of laboratory, glasshouse, and field experiments over a three year period. Water potentials (Y) ranged from -0.8 to -2.6 MPa at 20°C for both osmotic solutions and carriers. The duration of the priming treatments were 3, 7, or 10 days. All priming treatments, except KNO3 and mannitol, consistently reduced the mean time to germination in the laboratory, reduced the mean time to field emergence, increased final stands, but did not affect the mean time to harvest. However, solid phase was more effective than osmotic priming at each Ψ tested. The best solid priming mixture was 1.0:0.8:1.8 (seed:carrier:water) for 7 days at 20°C using Micro-cel E. This treatment was measured to have a Y = -1.2 MPa, and other types of priming at the same Y were less effective. The Y threshold below which no priming effect was obtained was Ψ= -2.4 MPa. Priming response was closely associated with, but not entirely dependent on, the Ψ of the treatment.
845 PB 491 CAUSES OF POSTHARVEST LEAF YELLOWING IN EASTER LILIES
Authors: Rartwala Anil P. , Miller William B. , Hammer P. Allen , Kirk Terri
Published: February 2019

The possible factors contributing to leaf yellowing during the postharvest phase of Easter lilies (Lilium longiflorum Thunb.) were investigated. Higher levels of growth retardants, forcing under negative DIF conditions, cold storage (4.0°C) at the `puffy bud' stage and shipping stress were shown to increase leaf yellowing during postharvest holding. Concentrations of soluble carbohydrates and starch under inductive and non-inductive conditions were determined to investigate the correlation of it to leaf yellowing. Lilies grown under negative DIP had lower concentrations of leaf, stem and flower soluble carbohydrates and starch compared to plants grown under positive DIF. Investigation of diurnal fluctuations of leaf carbohydrates revealed low carbohydrate levels in negative DIP-forced plants at all times during the diurnal cycle. Supplemental light (50-60 μmo1 m-2s-1) during cold storage increased leaf carbohydrate levels. Higher levels of bud abortion and reduced flower longevity were also observed under conditions inductive of leaf yellowing.
847 PB 515 SHORT INTERRUPTIONS OF THE COLD CHAIN REDUCE THE VASE LIFE OF ASTER ERICOIDES, CHRYSANTHEMUM, DIANTHUS, AND GYPSOPHILA CUT FLOWERS
Authors: van Gorsel Rik , Ravesloot Marc
Published: February 2019

Postharvest temperature and transport duration affect the vase life of cut flowers. necessitating temperature control throughout the marketing chain. However, in practise interruptions of this cold chain often occur, e.g. at the auction, airport or other transfer points. We investigated the effect of an early interruption of the cold chain on water loss, rate of development and vase life of four cut flower species. The experiment had a factorial design: three durations of interruption (8.16 and 40 h), each at five temperatures (8, 12, 16, 20 and 24C), and three containers (replicates) per treatment. A standard marketing chain simulation and vase life evaluation followed each treatment. Controls were 0 h interruption with and without marketing chain simulation. The experiment was carried out twice for each species. Water loss was proportional to vapor pressure deficit, with a sometimes synergistic effect of temperature. A short exposure to 20C accelerated the development of all flower species compared to continuous 8C. The effect of the higher temperature became more apparent later in the marketing chain. Averaged over the interruption temperatures, a one-day delay in the marketing chain resulted in a one day (Aster and Gypsophila) to three days (Dianthus and Chrysanthemum) decrease in vase life. A temperature of 20C for 40 hours reduced the vase life by 30% to 40% compared to continuous 8C.
849 PB 390 PREEMERGENT WEED CONTROL IN CONTAINER-GROWN HERBACEOUS PERENNIALS
Authors: Klett James E. , Staats David , Hillock David
Published: February 2019

During the 1992 season six preemergent herbicides (Devrinol) at 4.5 and 9.1 kg/ha, Metolachlor (Pennant) at 4.5 and 9.1 kg/ha, Isoxaben (Gallery) at 1.1 and 2.3 kg/ha, Oxyfluorfen + Oryzalin (Rout) at 3.4 and 13.6 kg/ha, Oryzalin (Surflan) at 2.8 and 4.5 kg/ha and Trifluralin (Treflan) at 4.5 and 9.1 kg/ha, were tested on Rudbeckia fulgida “Goldstrum”, Digitalis purpurea “Excelsior”, Chrysanthemum maximum “Alaska”, Stokesia laevis “Blue Danube”, and Geum hybrids “Mrs. Bradshaw”. Gallery at both rates resulted in visual phytotoxicity on Chrysanthemum, Digitalis and stunting in Rudbeckia at the 2.3 kg/ha rate. During the 1993 season the same herbicides plus Oxadiazon (Ronstar) at 4.5 and 9.1 kg/ha, were tested on Achillea tomentosa, and Thymus pseudolanuginosus. Gallery and Pennent at both rates resulted in visual phytotoxicity and stunted growth on Thymus pseudolanuginosus. Rout at the 13.6 kg/ha rate resulted in visual phytotoxicity on Achilles tomentosa.
853 PB 422 USING POTENTIAL OF COPPER TO CONTROL THE ROOTS CIRCLING OF TREES CONTAINER PRODUCIION
Authors: Iraqi Driss , Duchesne Isabelle , Rioux Jacques-Andre
Published: February 2019

Root system growth in limited volume containers can have important consequences on stem growth and root morphology. The most widespread deformation observed is root circling. Consequently, root circling often reduces growth, root regeneration and tree anchorage at transplanting time. The objective of this study is to restrict root tips. Three tree species were used in the study; Fraxinus Pennsylvanica, Acer saccharinum and Malus baccata. All species were grown in containers lined with one of six combinations of polymer (P) (0, 30 and 60 g/m2 and copper (Cu) (0, 0.4 and 0.8%) coated fabric. Two other treatments were included as controls: a plastic container and a fabric container. Treatments were randomized in complete blocks with six repetitions. Preliminary results of root circling length and dry weight indicate good restriction of root tips for two combinations (30 g of P/m2 - 0.8% Cu; 60 g of P/m2 - 0.8% Cu) for all species. However, treatments did not cause any reduction in stem height, trunk diameter or stem and root dry weight. Phytotoxic symptoms were not observed throughout the experiment.
COPPER HYDROXIDE-TREATED POTS IMPROVE THE ROOT SYSTEM OF BOUGAINVILLEA CUTTINGS
Authors: Aldrich James H. , Norcini Jeffrey G.
Published: February 2019

The response of the root system of `Barbara Karst' bougainvillea [Bougainvillea buttiana (Bougainvillea glabra Choicy × Bougainvillea peruviana Humb. & Bonpl.) `Barbara Karst'] cuttings to 100 g Cu(OH)2·liter-1 in a white latex paint applied to the interior surface of square 66 ml, 120 ml, or 280 ml plastic pots was determined. Cuttings (10 cm long; 3-5 nodes; 2 leaves) were scored on opposite sides and dipped in 6000 mg·liter-1 KIBA for 3 sec. The cuttings were placed in treated or untreated pots that contained a medium of 1 Canadian sphagnum peat: 1 coarse perlite (v/v). The pots were completely randomized in a 3×2 factorial design. The cuttings were rooted under intermittent mist 9 sec·min-1 for 12 hr·day-1 in a greenhouse (20% shade). The number of primary roots, fresh and dry weights, and root quality were determined 15 June. The Cu(OH)2-treated pots resulted in a more compact, well-branched root system and eliminated root circling. However, root fresh weight was reduced by Cu(OH)2 treatment. Pot size influenced the number of primary roots and fresh and dry weights.
859 PB 440 ANTIDESICCANTS APPLIED TO PACKAGED ROSE PLANTS AFFECT GROWTH AND FIELD PERFORMANCE
Authors: Karlik John F. , Schuch Ursula K.
Published: February 2019

Moisture loss from bare-root plants during postharvest handling and storage can have a significant effect on plant growth and survival during establishment. Three film-forming antitranspirants and hot wax were applied to bare-root roses packaged after harvesting from the field and before three months of cold storage to determine effects on vegetative growth and flowering. Subsequently, during three weeks under display conditions, plants treated with hot wax resumed growth at the fastest rate compared to control or antitranspirant treatments. Hot wax-treated plants continued to grow at a faster rate than the other plants for two weeks following transplanting in the field. For the remaining 10 weeks of the experiment no differences in vegetative growth or flowering development were found between treatments. Over 70% of the plants treated with hot wax became sunburned, resulting in severe cane damage and plant dieback. Less than 20% of the plants from the other treatments were damaged.
860 PB 539 GROWTH RESPONSES OF CULANTRO (Eryngium foetidum L.) TO GIBBERELLIC ACID SPRAYS
Authors: Ramcharan Christopher
Published: February 2019

Culentro, an umbelliferous aromatic saponin-containing biennial herb native of Central America and the West Indies is a major ingredient of many West Indian and Latin American dishes. Although closely related to the Asian culinary herb - cilantro or coriander, culantro is mainly prized for its green serrate spatulate-shaped leaves the main source of its oil. Like many other umbelliferoids under high temperatures and long summer days of the tropics culantro produces large umbel inflorescences and seedheads which are labor-intensive to remove, retard leaf growth and hence decrease the market value of the plant. Preliminary studies using ProGibb sprays from 50 to 200 ppm to 3- to 4-month old culantro plants grown under 53% shade showed increased leaf growth and chlorophyll content response to increasing levels of ProGibb. Maximum leaf length, fresh leaf weight, chlorophyll content and decreased flower growth were obtained at 100 ppm spray application. Treated plants remained in a vegetative phase for almost two years when vegetative side shoots were established. Postharvest observations showed no apparent decrease in shelf life nor loss of characteristic leaf aroma in leaves harvested from GA-treated plants. Inflorescences from sprayed plants were highly reduced in size, had leaf-like appearance and produced characteristic culantro aroma Indicating that they may also be utilized in culanto cuisines.
861 PB 540 In Vitro Adventitious Shoot Formation and Plant Regeneration from Culantro (Eryngium foetidium L.) Leaf
Authors: Mohamed-Yasseen Yasseen
Published: February 2019

Culantro is a perennial herb with odor like that of corinder, native to tropical America and the West Indies. Explants were excised from leaf petiole of mature culantro plant. Explants were cultured on MS alone or supplemented with 4.4, or 13.3 uM BA with 0.5 uM NAA, or supplemented with 0.3, 1.8, 4.5, or 3 uM Thidiazuron (TDZ) wth 0.5 uM NAA. leaf explants formed callus and were transferred to the same medium for shoot induction. Only explants which were cultured on MS supplemented with 13.3 uM BA or 0.9, l.8, 4.5, or 3 UM TDZ produced shoots. Shoots were regenerated in all TDZ-containing media with high 100% frequency. Shoot number increased with the increase of TDZ concentration but shoot length decreased. Although cytokinins are reported to inhibit root initiation, regenerated shoots formed roots with 100% frequency in BA-and TDZ-containing media. Regenerated shoots were transferred to MS containing 3.9 UM TDZ for further growth. Rooted shoots were transferred to soil and normal plants were obtained.
862 PB 541 VARIATION IN MINT GERMPLASM FOR CHEMICAL COMPOSITION
Authors: Rawgappa M. , Bhardwaj H.L. , Mohamed A.I. , Showhda M.E. , Kraemer M.E.
Published: February 2019

Thirty-five mint accessions were evaluated during 1993 for agronomic characteristics (leaf texture, color, and pubescence), plant vigor, cold hardiness, insect population interactions, and contents of essential oils, ash, and total protein. These accessions were obtained from National Clonal Germplasm Repository, Corvallis, Oregon during 1992. The rhizomes were planted in the greenhouse on April 2, 1992 and transplanted to the field on May 29, 1992 as a randomized complete block design with three replications. The chemical composition data from whole plants indicated that ash content was dependent upon location from which an accession was collected, ploidy level (diploid vs. polyploid), type of mint (peppermint vs. spearmint), and genetics (hybrid vs. non-hybrid). Diploid accessions had significantly higher essential oil content. The protein content was higher in peppermint types than spearmint types. The hybrid accessions had lower protein content in comparison to non-hybrids.
863 PB 542 SENSITIVITY OF ARTEMISININ YIELD FROM SWEET WORMWOOD (ARTEMISIA ANNUA) TO CHANGES IN CULTURAL PRACTICES
Authors: Shock Clint C. , Feibert Erik B. G. , Saunders Monty
Published: February 2019

Sweet worm wood is a source of the anti-malarial plant secondary compound artemisinin. The effects of water stress, nitrogen rates, plant growth regulators, and harvest timing on vegetative growth and yield of artemisinin were tested in separate experiments. In the harvest timing trial, total biomass, leaf yield, leaf artemisinin content and total artemisinin yield increased during the season. The wettest treatment tested decreased the total plant dry to fresh weight ratio, but had no effect on height, total biomass, leaf yield, leaf artemisinin content and artemisinin yield. Nitrogen fertilization increased plant height, but had no effect on total biomass, leaf yield, leaf artemisinin content and artemisinin yield. The plant growth regulators decreased plant height, increased total biomass, but had no effect on leaf yield, leaf artemisinin content and artemisinin yield. The effects of chemical weed control and post-harvest leaf drying will also be discussed.
870 PB 200 INFLUENCE OF SCARIFICATION AND TEMPERATURE TREATMENTS ON SEED GERMINATION OF LUPINUS HAVARDII
Authors: Davis Tim D. , Mackay Wayne A. , Sankhla Daksha
Published: February 2019

Seeds of Lupinus havardii Wats. (Big Bend bluebonnet), a potential cut flower crop, were subjected to a variety of scarification and temperature treatments. Without scarification, only 10-20% of the seeds germinated within one week. Germination percentages increased sigmoidally as scarification time in concentrated sulfuric acid increased. Nearly 100% germination was obtained within one week after seeds were placed in sulfuric acid for 120 min. Nicking the seed coat with a razor blade also resulted in near 100% germination. Soaking the seed in water for 24 h failed to enhance germination. Soaking the seed in ethanol, methanol, or acetone for 2 h likewise failed to enhance germination. Total germination of scarified seed was >90% between 21 and 33C within 28 h. The most rapid germination occurred within a range of 24-29C. Above or below this range germination was delayed. At 35C, seedling, mortality was observed and total germination was reduced to <50%. Our data indicate that seed of this species requires scarification for optimum germination but the seed can germinate over a relatively wide temperature range.