bluuebunny/crossref_metadata_2025 huggingface dataset:
Correlation of Bioassay Crop Growth with Cinmethylin and Chlorimuron Application Rates for Two Soils
Authors: Boucounis T.G. , Whitwell T. , Toler J.E.
Published: October 2019

Ten crops were evaluated for potential use as field bioassay species for cinmethylin and chlorimuron application rates in two soil types. Cinmethylin injured sweet corn (Zea mays L.) and grain sorghum [Sorghum bicolor (L.) Moench] at concentrations as low as 0.28 kg·ha-1 on either soil type, while broadleaf crops were tolerant. Chlorimuron injured sweet corn, grain sorghum, radish (Raphanus sativus L.), cucumber (Cucumis sativus L.), and watermelon [Citrullis lanatus (Thunb.) Mansf.] at rates ≥ 2.5 g·ha-1, and squash (Cucurbita pepo L.) at rates ≥ 5.0 g·ha-1 on a Dothan sand. In a Congaree silt loam, chlorimuron injured cucumber at rates ≥ 5.0 g·ha-1, sweet corn, watermelon, and squash at rates ≥ 10 g·ha-1, and grain sorghum, radish, and cotton (Gossypium hirsutum L.) at rates ≥ 20 g·ha-1. Soybean and snapbean (Phaseolus vulgaris L.) were tolerant to chlorimuron in both soil types. Cinmethylin activity was not altered by soil type, but with chlorimuron greater crop injury was observed in the Dothan sand than in the Congaree silt loam. Sweet corn and grain sorghum were the most sensitive indicator species to cinmethylin and cucumber was the most sensitive to chlorimuron in both soils. Plant emergence and population alone are not valid indicators for crop tolerance to herbicides. Quantitative measurements such as shoot dry weight were more indicative of crop susceptibility to chlorimuron than plant populations. Chemical names used: exo -1-methyl-4-(1-methylethyl)-2 -[(2-methylphenyl) methoxy]-7-oxabicyclo[2.2.1]heptane (cinmethylin); 2-[[[[(4-chloro-6-methoxy-2-pyrimidinyl)amino] carbonyl]amino] sulfonyl]benzoic acid (chlorimuron).
Response of Apple Cultivars to Fumigation with Methyl Bromide
Authors: Meheriuk M. , Gaunce A.P. , Dyck V.A.
Published: October 2019

`Golden Delicious', `Delicious', and `Spartan' apples (Malus domestics Borkh.) showed a high, moderate, and low tolerance, respectively, to methyl bromide fumigation. Incidence of external and internal disorders increased, in most instances, with longer storage periods after fumigation treatments and with longer exposure times to the fumigant. Dips in diphenylamine before fumigation reduced, but did not prevent, disorders. Fumigation had little effect on firmness and no effect on soluble solids content or titratable acidity. Methyl bromide concentrations with a low risk of disorder development were 32 to 64 g·m-3 for `Golden Delicious', 32 to 48 g·m-3 for `Delicious', and 32 g·m-3 for `Spartan', all at 10C for 2 hours.
FLOWER BUD COLD HARDINESS OF NATIVE AZALEA ECOTYPES
Authors: Pellett Norman E. , Rowan Nancy , Aleong John
Published: October 2019

Flower buds of eight ecotypes representing three native North American azalea species being grown in Burlington, Vermont were compared for cold hardiness by laboratory freezing during the cold acclimation period for three years. Species were Rhododendron calendulaceum, R. prinophyllum, and R. viscosum. There was a high variation in the number of florets killed within an inflorescens in response to freezing temperatures. There was little difference in the cold hardiness of florets of R. Pinophyllum and R. calendulaceum florets, but R. viscosum florets were hardier. Some differences were noted in cold hardiness of florets of ecotypes, but these were not necessarily related to latitude of origin. Cold hardiness showed a relationship with the daily mean temperature of the three days preceding freezing tests.
BTOSTIMULATION OF PLANT PROPAGATION BY SEAWEED/HUMUS EXTRACTS
Authors: Poincelot Raymond P.
Published: October 2019

A seaweed/humus extract (ROOTS) was tested as a propagation biostimulant. Transplants from seed showed enhanced root, root hair, and shoot growth. Cultivars tested included: Broccoli `Bonaza', Coleus `Park's Bril1iant', Dahlia `Redskin', Eggplant `Early Bird', Gazania `Pinata', Geranium `Earliana' and `Hybrid Orbit', Impatiens `Shady Lady' and New Guinea `Tango', Marigolds `Gay Ladies' and `Climax', Nicotiana `Nikki', Pepper `Park's Whopper', Petunia `Total Madness', and Tomatoes `Sweet Million', `Good n Early', `Better Boy', `Early Girl', `Lady Luck' and `Super Steak'. Cuttings from citrus cultivars showed improved rooting (Lemon `Ponderosa', Lime `Bearss', and Orange `Calamondin'). Cuttings from succulents also showed improved propagation (Pedilanthus tithymaloides cucullatus, Senecio deflersii, and an unknown stapeliad species). Seaweed extracts, known growth stimulants, when fortified with humic acid, offer promise as a propagation biostimulant.
Cultivar and Canopy Position Effects on Seasonal Development of Vegetative Spurs of Apple
Authors: Barritt Bruce H. , Schonberg Bonnie J.
Published: October 2019

Vegetative (nonflowering) spur characteristics of `Granny Smith', `Lawspur Rome', and `Redchief Delicious' apples (Malus domestics Borkh.) at two canopy positions (1 and 2 m heights) were examined on eight dates throughout a growing season. `Granny Smith' had a greater leaf number/spur (LNO/SP) at each date than `Rome' and `Delicious'. Area/leaf (LA) and dry weight/leaf (LDW) for `Delicious' were substantially less than for `Granny Smith' and `Rome'. Area/leaf increased rapidly after full bloom (FB) until FB + 21 days for `Delicious', FB + 35 for `Granny Smith', and FB + 56 for `Rome', after which no further changes occurred. For each cultivar, leaf area/spur (LAMP) and leaf dry weight/spur (LDW/SP) increased rapidly from FB until FB + 35 days and then more gradually until FB + 104 days. From FB + 21 onward, `Granny Smith' had greater LA/SP and LDW/SP than `Rome', which, in turn, was greater than for `Delicious'. At harvest (FB + 160), LA/SP was 2.5-fold greater for `Granny Smith' and 1.7-fold greater for `Rome' than for `Delicious'. Cultivar differences for leaf dry weight/leaf area (LDW/LA) were small and canopy position differences were large. LDW/LA declined from 7 days before FB to FB + 7, then gradually increased to the end of the season. Dry weight of the vegetative spur buds (with leaves removed) was lower for `Delicious' than for `Rome' or `Granny Smith'. Total spur dry weight (bud + leaves) was, from FB + 21 onward, greatest for `Granny Smith', intermediate for `Rome', and lowest for `Delicious'.
Nitrogen and Phosphorus Preconditioning of Small-plug Seedlings Influence Processing Tomato Productivity
Authors: Garton Ronald W. , Widders Irvin E.
Published: October 2019

Seedlings of processing tomato `H 2653' (Lycopersicon esculentum Mill.) were cultured in 288-cell (< 6 cm3 volume) plug trays in a soilless growing medium. Pretransplant fertilization with nutrient solutions containing 10 or 20 mm N and 2 or 5 mm P for 10 days altered the total ammoniacal-N and P, and the soluble NO3-N and PO4-P concentrations in the shoot tissue at transplanting. Post-transplanting shoot and root growth were more rapid in late May plantings than in earlier plantings. The 20-mm N and 2-mm P pretransplant treatment caused the most rapid shoot growth following early season plantings in the field. Rapid seedling establishment after transplanting was generally not a good indicator of potential fruit yield. The 5-mm P pretransplant treatment produced higher marketable fruit yields in early plantings but not in later. Culture of seedlings under a low fertilization regime (5.4 mm N, 1.0 mm P, and 1.6 mm K) before pretransplant treatment produced as high or higher fruit yields than did seedlings from a higher regimen. Withholding fertilizer temporarily before transplanting resulted in a depletion in tissue N and P concentrations, slow post-transplanting shoot growth, and lower yields.
Leaf Tipburn in Cauliflower as Affected by Cultivar, Calcium Sprays, and Nitrogen Nutrition
Authors: Rosen Carl J.
Published: October 2019

Two separate field experiments were conducted to determine the influence of Ca sprays and N fertilizer rate on leaf tipburn incidence in `Snow Crown', `Self Blanche', and `Imperial 10-6' cauliflower. Incidence of leaf tipburn was highest in `Snow Crown' each year and varied with year in `Self Blanche' and `Imperial 10-6'. Delaying planting of `Snow Crown' by 3 weeks decreased tipburn incidence by 20% and decreased the number of tipburned leaves per tipburned plant by 60%. Sprays of CaCl2 or calcium chelate had no effect on cauliflower productivity, nutrition, or tipburn incidence. Increasing N fertilizer rate from 67 kg N/ha to 201 kg N/ha linearly increased yield without significantly affecting tipburn incidence. Concentrations of Ca in tips of nontipburned leaves were two to five times greater than those in tips of tipburned leaves of comparable physiological age. Basal leaf regions had similar Ca concentrations, regardless of tipburn status. Use of resistant cultivars appears to be the best method of reducing tipburn incidence in cauliflower.
Electronically Controlled Root Heating Tubes
Authors: Ingram Dewayne L. , Basford Brett H. , Foster William J. , Ramcharan Christopher
Published: October 2019

A solid-state, electronic controller was designed and built to maintain de“sired root-zone temperatures in specially designed root heating tubes. The controller uses a thermistor feedback mechanism to an operational amplifier circuit. The tubes were constructed from 7.5-cm-diameter metal pipe, electrical heating tape, a rubber coating, and pipe insulation. Each controller can maintain treatment temperatures in 16 tubes; four tubes at each of four temperatures. Temperatures can be maintained from ambient to 50C with a precision at 35 of ± 0.9C within and between tubes.
Pre-harvest Pecan Yield Estimation
Authors: Wright Glenn C. , Storey J. Benton , Harris Marvin K. , Sprinz Peter T.
Published: October 2019

Nut count (NC), trunk circumference (TC), competition factor (CF), days from budbreak (DAY), and high or low crop year (YR) data were collected on 40 trees at three sites across Texas in 1985 and 1986, to create a model that would predict pecan [Carya illinoensis (Wangenh.) C. Koch] yield. The model developed predicted the natural logarithm of the total nuts on the tree [In(NUTS)]: In(NUTS) = 2.112 + [0.634 × In(NC)] + (0.00119 × TC) – (0.0701 × In(CF)) + (0.00639 × DAY) + (0.728 × YR). The equation accounts for 87% of the variation in yield. The model is not sufficiently accurate to predict individual tree yields well, but additional data show an ability to accurately predict average tree yields.
PRELIMINARY STUDIES ON COLD HARDINESS OF SOUTHERN MAGNOLIA
Authors: Lindstrom Orville M. , Kent Glen W.
Published: October 2019

Magnolia has graced southern landscapes for many years. However, its northern distribution is limited due to injury at low, freezing temperatures. Laboratory methods are available to assess the cold hardiness of many plants, but specific methods for Southern magnolia have not been established. Effects of exposure time, temperature at which plants were frozen, rate of warming, sample size and methods of injury evaluation were investigated. With exposure to -1.5 and -4C the leaves and stems were not injured when frozen for up to 7h. Stems and leaves that were nucleated with ice at -4C underestimated the cold hardiness as compared to similar plants that were nucleated at -1.5 and -3C. Samples warmed as taken from the temperature bath at 4C or at 4C/hr in the bath exhibited less injury than those taken directly out of the bath and exposed to room temperature. Similar cold hardiness determinations were obtained using whole and half leaf samples, while a quarter of a leaf or a leaf disk exhibited high variability and resulted in unreliable cold hardiness determinations. Visual analysis for injury was compared to electrolyte leakage and similar cold hardiness levels were obtained using the two methods.
MOLYBDENUM SOURCES FOR POINSETTIAS
Authors: Sanderson Kenneth C.
Published: October 2019

`Annette Hegg Brilliant Diamond' poinsettias were directly rooted and grown in 1 sphagnum peat moss:l perlite medium treated with six treatments of Mo and a check. The treatments were: 1) 0.2 ppm Mo liquid weekly, 2) 3.0 mg Mo plaster-of-Paris tablet, 3) 0.6g per liter liquid STEM once, 4) 0.6 kg per m3 Micromax incorporated (Preplant), 5) 3.3 kg per m3 Perk incorporated, 6) 3.0 kg per m3 Esmigran incorporated, 7) 1.2 kg per m3 FTE 503, and 8) check (untreated). Plant height and foliar Mo, N, and Mn were affected by Mo treatments. Untreated plants were shorter than plants receiving Mo treatments. Weekly liquid Mo treatments (10.0 ppm) yielded plants with the highest foliar Mo content and differed from all other treatments. FTE 503 plants (4.2 ppm Mo) differ from other Mo treatments and check plants (1.4 ppm Mo). Liquid Mo plants (6.1% N) had the highest N content and differed from all treatments except Perk (5.8% N) and Micromax (5.8% N) and Micromax (5.8% N). plants. Perk-treated plants (155 ppm Mn) contained more Mn than other plants, whereas check plants (48.4 ppm Mn) and Mo tablet plants (38.4 ppm Mn) contained the least Mn content. Bract number, plant spread and Fe content were unaffected by Mo treatments.
SWEET POTATO GROWTH AND ROOT DEVELOPMENT IN FRITTED CLAY MEDIA
Authors: Ndolo P. J. , Rhoden E. G.
Published: October 2019

Root growth of sweet potato [Ipomoea batatas (L) Lam.] cvs `TI-82-155', `Centennial' and `Rojo Blanco' in coarse fritted clay soil, was investigated under greenhouse conditions. The sweet potato cultivars were harvested at 41 and 82 days after planting. Dry weight of fibrous roots of all cultivars were similar at day 41. Fibrous root weight of `Rojo Blanco' increased by 5% while those of the other cultivars increased by 168%. Mean fibrous root length per centimeter depth was not significantly different among cultivars. Although fresh weight of storage roots of `Rojo Blanco' was significantly lower than those of the other cultivars, their dry weights were similar. `TI-82-155' and `Rojo Blanco' had fewer storage roots compared to the other cultivars, however, storage root length of `TI-82-155' or `Rojo Blanco' was greater than that of `Georgia Jet' or `Centennial'. Length to diameter ratio of the storage root of `Rojo Blanco' was significantly greater than that of `TI-82-155' and `Georgia Jet'.
TEMPERATURE REGIMES UNDER ROW COVERS IN OVERWINTER ONION TRANSPLANT PRODUCTION
Authors: Bender David A.
Published: October 2019

Two cultivars of onions, `New Mexico Yellow Grano' and `Midstar' were seeded in single bed plots in mid-October 1985 and 1987 for overwinter transplant production. Plots were covered with spunbonded polyester (POL) or tunnels of clear polyethylene (CLR) or microperforated polyethylene (PER) (1985 only) in early November and compared to uncovered controls. Temperatures were monitored 5 cm above the soil surface under the covers in each plot with three parallel-wired thermocouples. Heat unit (HU) accumulation (number of degrees by which the daily mean temp exceeded 0°C) was recorded for each plot and compared with onion plant size. HU accumulation by mid-February 1986 under CLR, POL and PER was 139%, 131% and 113%, respectively, of that over bare ground. In mid-March 1988 cumulative HU under CLR and POL were 192% and 125% of those over bare ground. Plant diameter varied with variety but increased linearly with cumulative HU for all varieties. `New Mexico Yellow Grano' reached the minimum 4 mm size for transplanting at about 1800 HU while `Midstar' required only 1500 HU. CLR produced useable transplants by early March and the other covers by late March. Numbers of useable transplants per meter of bed in mid-March ranged from 3-6 in uncovered plots to 102-153 under PER tunnels, 185-203 under POL and 263-301 under CLR tunnels. CLR tunnels appear to provide sufficient HU accumulation to produce onion plants for transplanting in early March in West Texas.
BIENNIAL BEARING IN CRANBERRY. HOW EXTENSIVE IS IT?
Authors: Strik B.C. , Roper T.R. , DeMoranville C.J. , Davenport J.R. , Poole A.P.
Published: October 2019

Biennial bearing has long been thought to occur in cranberry (Vaccinium macrocarpon Ait). Researchers have shown that percent return bloom on fruiting uprights can range from 12% to 65% depending on year, bed vigor and cultivar. Resource limitation and/or hormonal factors in a fruiting upright may be related to flower bud initiation and, thus, percent return bloom the following year. This research was undertaken to determine the extent of biennial bearing by cranberry cultivar and growing region. Seven cultivars were studied; three found in all states (MA, NJ, WI, OR), two common to MA and NJ, and two different cultivars in WI and OR representing cultivars commercially grown in these areas. In the fall or winter of 1989/1990 six 2-m transects were randomly selected within a cranberry bed for each cultivar. Along the transect, 60 uprights that fruited in 1989 were tagged. In the summer of 1990, fifty of the uprights will be sampled to determine percent return bloom and percent set.
CARROT RUST FLY CONTROL FOR ORGANIC FARMERS
Authors: Giraud Deborah
Published: October 2019

The carrot rust fly (Psila rosae) lays eggs in the crowns of carrots, celery, and parsnips. Its larvae are dark brown maggots which burrow into the crown and roots of the plants making them unsalable. This is a pest of economic significance in coastal plantings. This project evaluated several non-chemical strategies available to organic farmers over three growing seasons. These included the use of traps to monitor populations and determine fields where infcstations are likely to occur, parasitic nematodes, the use of trap crops, and row covers as an exclusion technique. Floating row covers were the only successful treatment in reducing maggot damage in these fresh market carrots.
GENETIC STUDIES OF CUCUMIS MELO L. RESISTANCE TO MYROTHECIUM RORIDUM
Authors: Mackay W.A. , Ng T.J , Hammerschlag F.A.
Published: October 2019

Genetics of the host-pathogen interaction between Cucumis melo L. (muskmelon) and Myrothecium roridum were investigated by evaluating six populations: the parents, F1, F2, BCP1 and BCP2 of crosses between `Hales Best' (tolerant), `Perlita' (intermediate) and `Iroquois' (susceptible). A spore inoculation bioassay with detached-leaves was used to determine levels of resistance. Resistance was determined by measuring necrotic lesion diameter, chlorotic plus necrotic lesion diameter, and a subjective rating score. Parents and F1s had consistent performance while the segregating generations were inconsistent. Factors contributing to the response will be discussed.
POLYGALACTURONASE IN POLLENS
Authors: Pressey Russell
Published: October 2019

Polygalacturonase (PG) in higher plants has been considered to be associated with ripening fruits although it is now known to be present in foliage and storage organs. We recently found very high levels of PG in some grass pollens (Plant Science 59, 57-62, 1989). This prompted an examination of other pollens for PG activity. All of the pollens analyzed contained PG but the range of activities was great. Eastern cottonwood pollen contained the most PG, with a level about 12 times higher than that usually found in ripe tomato fruit. Pollens from the other members of Populus were generally high in PG. Pollens from the oak family also contained very high PG, with the highest amount in white oak pollen. Pollens from pecan, English walnut, willows, birch and hickories contained moderate levels of PG. The lowest amounts of PG were found in pollens from beech, sycamore and conifers. The PG's from the two richest sources (eastern cottonwood and white oak pollens) were partially purified and characterized. Both enzymes were found to be exopolygalacturonases that require Ca2+ for activity. PG may be involved in some function related to pollination but an explanation for the wide range of activities indifferent pollen is not obvious.
TEMPORAL PATTERN OF GROWTH IN ALSTROEMERIA
Authors: Aker Scott , Healy William
Published: October 2019

Alstroemeria `Regina' and A. `Orchid' Linn. plants were grown in rhizotrons to facilitate non-destructive observation of shoot, rhizome, and storage root growth. In plants grown at 21/11 C or 21/21 C day/night temperatures under either 8 hr night interruption or an 8 hour short days, storage root growth was favored by cool (11 C) night temperatures and long days. The seasonal patterns of storage root and rhizome growth were inversely related to the seasonal pattern of shoot growth. Growth of shoots and rhizomes followed a cyclic pattern. The cycles of shoot and rhizome growth were in phase with each other until the plants resumed vegetative growth due to high soil temperature. At this point, the cycles of shoot and rhizome growth were shifted out of phase with each other. Thinning shoots by 60% resulted in delay and damping out of the peak of storage root growth; the cyclic growth of storage roots was disrupted when plants were thinned by 60% such that the cycles of active storage root growth were delayed by 1 week.
GROWTH AND PHOTOSYNTHESIS OF MAGNOLIA GRANDFLORA HORT. `ST, MARY' IN RESPONSE TO CONTAINER VOLUME AND SHIFTING TREATMENTS
Authors: Martin Chris A. , Ingram Dewayne L , Nell Terril A.
Published: October 2019

Trees were grown for 2 years as a function of three container volumes (10, 27, and 57 liter) the first year and six shifting treatments (10 liter both years, 10 to 27 liter, 10 to 57 liter, 27 liter both years, 27 to 57 liter, or 57 liter both years) the second year when containers were spaced 120 cm on center, Height and caliper were greatest for magnolias grown in 27- or 57-liter containers both years. Caliper was greater for trees shifted from 10-liter containers to the larger container volumes compared to trees grown in 10-liter containers both years, Trees grown in 10-liter containers both years tended to have few roots growing in the outer 4 cm at the eastern, southern, and western exposures in the grow medium, During the second year, high air and growth medium temperatures may have been primary limiting factors to carbon assimilation during June and August. Using large container volumes to increase carbon assimilation and tree growth may be even more important when daily maximum air temperatures are lower during late spring or early fall compared to midsummer.
HEATED IRRIGATION FOR FROST PROTECTION
Authors: Martsolf J. David
Published: October 2019

An undertree sprinkler [Maxijet] irrigation system designed to deliver 42 to 80 l/hr to each of 570 citrus trees (planted 6.1 × 6.1 m, heights of the larger uniform trees: 2m) was fed through an irrigation water heater [Aquaheet]. The heater added up to a megawatt of heat to the irrigation pipeline by the combustion of diesel fuel. A porous orchard cover (59m × 64m × 3.6m; 0.38ha) sheltered one of six plots of similar size in a citrus orchard on the University of Florida campus in Gainesville. Two border zones, one 3 rows deep on the north border and one on the west tapering from 2 rows on the north to a single row on the south end reduce the edge effect for a total orchard area of 2.12 ha. A minicomputer based data acquisition system provided observations of temperature, wind speed and direction made as frequently as one scan per minute. The effect of the orchard cover, the undertree irrigation, the heated irrigation and combinations of these three methods on the orchard microclimate will be shown in graphs and diagrams of observations taken during the freezes of February 24-26, and December 24-25, 1989. A diagram of the potential effect of water temperature on latent heat transport in the orchard will be discussed as will be problems with documentation of dew point temperature with chilled mirrors under freezing conditions.
OPTIMAL CONDITIONS FOR ROOTING SHOOT CUTTINGS OF AZALEA (RHODODENDRON SP.) IN SOLUTION CULTURE
Authors: Green Carrie E. , Hershey David R.
Published: October 2019

Fundamental research on mineral nutrition of azalea has been restricted due to the lack of a model experimental system for growing azaleas in solution culture. The need to maintain a clean root system dictates that azalea cuttings be rooted in solution. A propagation system (HortScience 24:706) was used to root 10-cm long terminal shoot cuttings of azalea `Delaware Valley White' under intermittent mist in a greenhouse. Cutting bases were dipped in 8,000 mg/liter K-IBA for 40 seconds before rooting. Rooting percentages after 7 weeks were 6, 10, and 50% for rooting solutions of tap water, modified 20% Hoagland solution, and 2mM CaCl2, respectively. After an additional 5 weeks the rooting percentage had increased to 83% in the 2 mM CaCl2 treatment. Three other azalea cultivars were found to root much slower than `Delaware Valley White'. Acclimatization of rooted cuttings to the normal greenhouse environment is essential to prevent leaf necrosis and is accomplished by gradually reducing the misting frequency prior to removal from under intermittent mist.
EFFECT OF TIMING OF GA APPLICATION ON FLOWERING OF MACADAMIA
Authors: Nagao Mike A. , Ho-a Elodie B. , Yoshimoto Judy M.
Published: October 2019

Flowering of Macadamia integrifolia trees was monitored following application of 220 mg/liter gibberellic acid (GA3) at various times preceding the onset of the flowering season. In untreated trees, flowering extended over a 4-5 month period. When GA3 was applied at 2, 3 and 4 months before the onset of anthesis, raceme production during the entire flowering season was inhibited. A slight reduction in raceme production was observed when GA3 was applied at 1 month preceding anthesis. This application coincided with appearance of the earliest infloresceuces. GA3 application after the onset of anthesis did not alter the flowering pattern of trees during the remaining 4 months of the flowering season. Results suggest that GA3 inhibits flower initiation, but has no effect on raceme emergence after flower bud differentiation has occurred. The relationship between flower initiation and raceme emergence will be discussed.
EFFICACY OF SOLID WASTE COMPOST AS A PROPAGATION MEDIUM
Authors: Verkade S. D. , Fitzpatrick G. E.
Published: October 2019

The availability of organic components of potting media is limited due to supply and shipping costs. Disposal of solid waste has also become a serious problem for many municipalities. The utilization of solid waste compost in agricultural production promises to be a solution for both concerns. The objective of this experiment was to determine the efficacy of sol id waste compost from Miami, Dade County, Florida as a propagation medium for vegetative reproduction of ornamental and landscape plants.

Cuttings of Podocarpus macrophylla, Chrysobalanus icaro, and Impatiens spp. 1-13 cm long, treated with .2% NAA ppm IBA were rooted in media composed of sphagnum peatmoss: perlite (1:1) or Agrisoil (TM) solid waste compost: perlite (1:). Cutting rooted well in both media. Data included number of roots and root weight.
NOTCHING TECHNIQUES TO INCREASE BRANCHING OF YOUNG APPLE TREES
Authors: Greene Duane W. , Autio Wesley R.
Published: October 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.
THE EFFECT OF SEVERE PRUNING ON THE NEW GROWTH OF TWO TREE SPECIES.
Authors: Rose Mary Ann , Kuhns Larry J.
Published: October 2019

Large bare-root liners of Gleditsia triacanthos `Moraine' and Pyrus calleryana `Aristocrat' were planted in spring, 1989. Five trees of each species were pruned by removing 50% of the length of each shoot at planting; 5 control trees were not pruned. After 4 months the trees were harvested and the following measurements were taken on the season's new growth increment: total number of elongated shoots and unelongated shoots (< 1 cm in length), total and average length of elongated new shoots, stem and leaf dry weights.

Growth responses of the 2 species to treatments were nearly identical. Pruned trees had fewer shoots than controls but a much higher proportion of elongated to unelongated shoots. This could be the result of a release of apical dominance. The average new shoot length of pruned trees was 2-3 times that of controls, and the total new shoot length was significantly greater. New stem dry weights of the pruned trees were also greater than the controls, but leaf dry weights were not significantly different. Total shoot weights (stems plus leaves) were not different. In this study there was no difference between treatments in the total seasonal growth increment as measured by weight. An equivalent amount of new growth was distributed on fewer, but more rapidly-elongating branches in the pruned trees.
THE EFFECTIVENESS OF ROW COVERS AS A BARRIER TO INSECT PESTS ON ROMAINE LETTUCE (PARRIS ISLAND COS)
Authors: Scaroni Mark , Wheatley Jo Ann C.
Published: October 2019

This project examined a floating row cover as an alternative to chemical use for pest control. Insect and vertebrate pest control was excellent on the covered versus the uncovered crop plants. Average weight, length, and quality were enhanced through the use of covers. The interval of transplant-to-harvest was also decreased. While the cost of row cover use is quite high on a per-acre basis, additional gains in quality, yields, earlier plantings, and earlier harvests may justify the use of row covers as an alternative to chemical control. Although acceptance and use of row covers may ultimately rely on the consumer, demand for organically grown vegetables will warrant further evaluation of row cover materials.
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: October 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.
TOMATO MATURITY IN RELATION TO PRUNING AND CULTURE
Authors: Nicklow Clark W. , Wenning Bruce
Published: October 2019

Three different cultural methods were utilized in the evaluation of 150 indeterminate tomato hybrids. This study was conducted over a two year period. The hybrids were planted in the field through 1.52 m wide black plastic; (1) 30.5 cm apart in rows, trained upright end pruned to one growing point (1gp); (2) 91.4 cm apart in rows, trained upright end pruned to three growing points (3gp); and (3) 91.4 cm apart in rows end permitted to grow prostrate end unpruned (up). Accumulated total harvest patterns were different: August 5 (early yield) of the first year, the yield of all ripe or turning fruit was 2.43, 0.36 and 0.24 kg/m2 respectively; the yield resulting from pruning to 1gp was 6.75 X the yield of the plants with 3gp. Yields of plants with 1gp were 3.6 X and 2.6 X the yield of plants with 3gp, 20 and 40 days later respectively. The yield of the plants up were the lowest in early maturity but 40 days later surpassed the yield from plants with 1gp by 2.6 kg/m2.
FACTORS AFFECTING THE REGENERATION OF PEPPER (CAPSICUM ANNUUM L.)
Authors: Jacobs J. L. , Stephens C. T.
Published: October 2019

Several growth hormone combinations and silver nitrate concentrations were examined for their effect on regeneration of different pepper genotypes. Primary leaf explants from in vitro seedlings were cultured on a revised Murashige and Skoog medium supplemented with auxin, cytokinin and 1.6% glucose. Combinations of different concentrations of indole-3-acetic acid (IAA), 0-5 mg/l, and 6-benzylaminopurine (BAP), 0-5 mg/l, were tested to determine the most effective medium for shoot primordium formation. Experiments with IAA and BAP did not result in a specific growth hormone combination appropriate for regeneration of all genotypes tested. Of the silver nitrate concentrations tested, 10 mg/l resulted in the best shoot and leaf differentiation and reduced callus formation. Differences in organogenic response of individual genotypes were evaluated on a single regeneration medium. Whole plants were regenerated from 11 of 63 genotypes examined. Based on these experiments, a reproducible regeneration system for pepper was developed with a total of 500 plants regenerated to date.
FIELD STUDIES TO QUANTIFY POLYGENIC RESISTANCE IN SPINACH TO WHITE RUST AND DOWNY MILDEW.
Authors: Brandenberger L.P. , Morelock T.E. , Correll J.C.
Published: October 2019

Field observations indicate that polygenic resistance to downy mildew (Peronospora farinosa f. sp. spinaciae) was observed during the course of a breeding program to develop polygenic resistance to white rust (Albugo occidentalis). Field studies were initiated using five cultivars and one breeding line to quantify the level of resistance to downy mildew and white rust. Separate plots were inoculated with each pathogen at a specific spore concentration and then subjected to a minimum dew period of 12h. Infection was quantified by measuring latent period, lesion number, lesion size, sporulation and percent leaf area infected.
CLONAL MICROPROPAGATION OF MALE-STERILE ZINNIA ELEGANS
Authors: Rogers R.B. , Smith M.A.L. , Cowen R.
Published: October 2019

The only method for large scale production of pure hybrid seed in Zinnia elegans involves the use of male sterile individuals. The male sterile trait, however, is a three gene recessive which at best produces only 50% male sterile progeny from seed. Since no method of clonal propagation is available, seed-produced female lines require labor intensive field roguing to insure removal of all normal flowered individuals. Clonal micropropagation was investigated as a means of mass producing male steriles for use as female lines. Sterilization procedures were developed for seed and axillary bud explants. Shoot proliferation media containing various levels of BAP, 2ip, and kinetin were screened using in vitro germinated seedling explants of the inbred line `Orange Starlight'. Microshoots demonstrated a high rooting percentage after 2 weeks on basal medium without growth regulators. Plantlets were easily acclimated in 1 to 2 weeks in a high humidity environment. In vitro derived plants of identified male sterile plants were phenotypically evaluated as to their suitability for use in field production.
DRAWING AS A MEANS OF ALTERNATIVE EDUCATION IN PUBLIC BOTANICAL GARDENS
Authors: Bull Rebecca , Haque Mary
Published: October 2019

Increased interest in nature over the past three decades has generated a need for better educational programming in public botanical gardens. The purpose of this study was to develop stronger educational programming for public botanical gardens. Garden programs which have been most successful are those which incorporate interaction and the multi-media. Eight different programs, which conveyed the same information, were developed to test the impact of drawing on learning. The 240 volunteers observed six native plant either in the field or as slides in the classroom. A 3×4 Factorial Manova was used to evaluate if drawing had any effect on learning. It was concluded that drawing alone improves learning by 12.37%,
CHILLING ENHANCEMENT OF ROOT REGENERATION IN APPLE CAN OCCUR WITHOUT BUDBREAK OR GROWTH OF ROOT SUCKERS
Authors: Arnold Michael A. , Young Eric
Published: October 2019

After receiving 0, 600, 1200, or 1800 hr. of chilling at 5C, one-year-old Malus domestica Borkh. seedlings were given 10 sec. root dips either 10,000 ppm K-IBA solution or water control. Following chilling and IBA treatments, 20 seedlings of each combination were placed in forcing conditions of 20 ± 2C root temperatures and either 20 or 5 ± 1C shoot temperatures. Five seedlings of each treatment were harvested after 0, 7, 14, and 21 days of forcing. Five C prohibited budbreak and bark slipage for up to 21 days. Under 20C, budbreak, shoot elongation and root growth all occurred earlier, faster, and reached a higher level with increased chilling. Twenty C root and 5C shoot temperatures during forcing resulted in large increases in the growth of adventitious shoots on lateral roots, but had little effect on the formation of adventitious shoots on the tap root. K-IBA prohibited development of adventitious shoots on roots, reduced shoot elongation more so than budbreak, and increased root regeneration across chilling hours. K-IBA inhibition of adventitious shoots did not alter the overall pattern of root regeneration enhancement by chilling.
ROLE OF CARBOHYDRATE DEPLETION AND ETHYLENE IN FLOWER BUD ABSCISSION OF HIBISCUS ROSA-SINENSIS L.
Authors: Poole Barbara C. , Nell Terril A. , Barrett James E.
Published: October 2019

Premature flower bud abscission imposes a serious limitation on longevity of potted Hibiscus in interiorscape situations, Ethylene is known to be one causative factor. Past research has suggested that carbohydrate depletion of buds may also be involved,

A series of experiments was conducted to examine the relationship between carbohydrate levels and ethylene sensitivity of flower buds under low irradiance levels. Two cultivars were used: `Pink Versicolor', which is very susceptible to bud abscission, and the more resistant `Vista', In the first experiment, plants were harvested twice weekly after placement in interiorscape rooms (8.5 μmol m-2 s-1 for 12 hrs per day; 26.5°C day/night) until all buds had abscissed. At each harvest, buds from four size groups were collected for analysis. In the second experiment, source/sink strength of buds was manipulated by selective daily removal of certain sized buds. Remaining buds were collected just prior to abscission for analysis. In two additional experiments, `Pink Versicolor' plants were treated with either silver thiosulfate or ethephon prior to placement in interiorscape rooms. Plants were harvested twice weekly and buds collected. For all experiments, bud dry wt, total soluble sugars and starch content were determined.
EFFECTS OF MOIST HEAT TREATMENTS ON THE POSTHARVEST BEHAVIOR OF `CHANDLER STRAWBERRY
Authors: Yoshikawa F. T. , Mitchell F. G. , Mayer G.
Published: October 2019

Three successive experiments were included in this trial. The first experiment was a derailed screening program to test the effects of various temperatures and durations on the fruit quality of strawberry fruit. Fruit were exposed to temperatures of 37, 40, 43, and 46°C for durations of 20, 40, 60, 80, end 100 minutes at each temperature level. The temperatures and durations which were detrimental to fruit quality were eliminated; then experiments 2 & 3 were conducted using the remaining temperature and duration levels to study their effects on fruit quality, respiration, and ethylene production.

Strawberries heated to 46° C were too severely damaged for other test comparisons. Those exposed to temperature treatments of 43 °C for 30 or 60 mins were consistently less firm, had more heat damage, developed less decay, and had lower CO2 and ethylene production than fruit from lower temperature treatments or control fruit. Differences were sometimes significant.

While the heat damage scores from fruit exposed to the 43°C treatments indicated some serious injury, the fruit were stiff judged to be marketable. There were no significant differences in soluble solids content (SSC), titratable acidity, SSC/acid ratio, or juice pH among any of the treatments.
YIELD AND POD DISTRIBUTION OF CAYENNE PEPPERS AS AFFECTED BY PLANTING DENSITY
Authors: Friend Heather H. , Decoteau Dennis R.
Published: October 2019

The effect of planting density on yield and pod distribution of cayenne pepper (Capsicun annuum var. annuum L. cv. Carolina Cayenne) was investigated in a two year study. In 1988, planting density was adjusted by altering the in-row spacing of single row beds, while in 1989 planting density was adjusted by altering both in-row spacing and number of rows per bed. In-row spacings evaluated in 1988 were 60, 45, 30, and 15 cm, while in-row spacings of 60, 30, and 15 cm in single and double rows were evaluated in 1989. In 1988, pepper plants grown in the highest density (15 cm in-row spacing) produced less fruit per plant, but more fruit per hectare than those grown in lower densities. In 1989, greatest yields per hectare were recorded with either 15 cm in-row spacings with single rows per bed or 30 cm in-row spacings with double rows per bed, In general, greater percentages of fruits were located in the upper part of the plant canopy when planted in higher plant densities.
PENETRATION OF OCTYLPHENOXY SURFACTANTS THROUGH ISOLATED TOMATO FRUIT CUTICLES
Authors: Petracek Peter D. , Knoche Moritz , Bukovac Martin J.
Published: October 2019

Despite the widespread use of surfactants to enhance the performance of foliar applied chemicals, the mechanisms for this enhancement are poorly understood. The penetration of surfactant per se through the cuticular membrane (CM) may play a pivotal role. Thus, we examined CM penetration by octylphenoxy surfactants (Triton X series) using a finite dose (Franz) diffusion cell. The effect of hydrophile length was studied using 14C surfactant (15.9 mm in 20 mm citrate buffer: pH 3.2) with 3, 9.5, 12, 16, and 40 ethylene oxide units per molecule (EO). One 5-μl droplet of surfactant solution was applied to the outer morphological surface of CM enzymatically isolated from mature tomato fruit. The inner CM surface remained in contact with stirred buffer at 25°C. The buffer was sampled periodically through a side portal over 648 h. Penetration curves (time vs. % penetrated) for all surfactants were characterized by three phases: lag, linear, and asymptotic. Lag: There was no effect of EO on the length of the lag phase (average 5 h) Linear: Steady state penetration (0.6 to 1.1% / h) was inversely related to log EO content. Asymptotic: About 70% of applied short EO (3 to 16) surfactants penetrated while 25% of the 40 EO penetrated in 648 h.
PERFORMANCE OF AN INTEGRATED AQUACULTURE~ OLERICULTURE SYSTEM AS INFLUENCED BY COMPONENT RATIO
Authors: McMurtry Mark , Sanders Douglas
Published: October 2019

Fish and vegetable production were linked in a recirculating water system. Hybrid tilapia were grown in tanks and fed a commercial feed. Tomato or cucumber were grown in sand biofilters associated with each tank. Four tank to biofilter volume ratios, ranging from 1:0.67 to 1:2.25, were studied by varying the biofilter size. Plant populations were directly proportional to biofilter volume and surface irrigated 8 times daily with aquacultural `waste' water, Biofilter drainage returned to the fish tanks by gravity. Each system received identical nutrient inputs and plants received equal water. Biological filtration, aeration, and mineral assimilation by plants maintained water quality under rapid fish growth rates. Dissolved oxygen levels, make-up water, fish biomass increase and growth rates increased with biofilter volume. Total fruit yield increased but yield per plant decreased with increasing biofilter volume. Caloric content of the increase in fish biomass per liter of total water decreased white that of tomato increased with increasing biofilter volume. Calories in the combined yields per liter of water used did not differ by treatment. Total protein production per liter of water used decreased with increasing biofilter volume. Both caloric value and protein production in the combined outputs increased with biofilter volume irrespective of water consumption. Annualized economic value from the combined fish and `Laura' tomato production per composite unit area ranged from $98 to $124 m-2 with decreasing tank to biofilter ratio.
TEMPERATURE, TRANSPLANT TIME, AND PLUG SIZE EFFECTS ON GROWTH AND DEVELOPMENT OF PANSY, PETUNIA, VINCA, AND IMPATIENS
Authors: Al-hemaid Abdulrhman I. , Koranski David S.
Published: October 2019

Petunia `Red Flash', Vinca `Little Blanch', Pansy `Magestic Giant Purple', and Impatien `Super Elfin Red' plugs were held in the greenhouse after they reached the saleable size in 200, 406, 512, and 800 for 1 to 3 weeks Pansy plugs were held in coolers at 40, 50, or 60F under fluorescent light for 16 hrs photoperiod for 1 to 3 weeks in 200, 406, 512, or 800 plug trays. All plants ware transplanted weekly and were grown in the greenhouse until flowering and data were collected. For plants bald in the greenhouse, plants were affected by transplanting time. As the holding time increased the final height, diameter, flower number, and fresh and dry weight of plants decreased. The flowering time was delayed by increase the holding time, regardless of plant variety, As cell size decreased, plant height, diameter, flower number, and fresh and dry weight decreased. For plants held in the coolers, the flowering time was delayed by the transplant time, regardless of cooler temperatures Plant quality was not affected by the treatment. The height, diameter, flowers number, and fresh and dry weight of plants showed a little effects by temperatures, cell size, and transplanting time.
ENHANCING BUDBREAK IN DESERT-GROWN TABLE GRAPES
Authors: Williams Larry E. , Neja Rudy , Yates Lori
Published: October 2019

A study was conducted to determine the effects of various cultural practices on enhancing earlier and more uniform budbreak of Perlette grapevines grown in the Coachella Valley of California. Post-harvest irrigation treatments were imposed approximately July 1 for three consecutive years. This included cut-off dates (Sept 15 and Nov 15) and various irrigation amounts based upon a standard treatment in which continued vegetative growth was inhibited. The application of hydrogen cyanamide or lack of also was included in the experimental design. In 1989 and 1990, the early irrigation cutoff date resulted in earlier dates of budbreak compared to the late cutoff. Vines irrigated with the most water had delayed budbreak compared with those irrigated with less. There were significant (p < 0.05) interactions between irrigation amounts and cyanamide applications. The results indicate that the amount and timing of post-harvest irrigations in conjunction with cyanamide will promote earlier and more uniform budbreak of vines grown in the desert.
RESISTANCE OF WILD LETTUCE (LACTUCA SALIGNA L.) TO LETTUCE INFECTIOUS YELLOWS VIRUS
Authors: Haley Valerie , McCreight James D.
Published: October 2019

Segregating generations from crosses of cultivated lettuce (Lactuca sativa L.) with wild lettuce (L. saligna L.) are affected by sterility and abnormal growth. Resistance to lettuce infectious yellows virus (LIYV) was, therefore, studied in crosses of previously reported LIYV-resistant (PI 261653) with LIYV-susceptible (PI 490999, PI 491000 and PI 491001) L. saligna accessions. Simple Mendelian ratios for resistance (measured as numbers of symptomless and symptomatic plants, and as number of symptomatic leaves per plant) to LIYV were not evident. PI 491001 had the fewest symptomatic plants and the fewest symptomatic leaves per plant. The potential value of L. saligna for development of LIYV-resistant cultivated lettuce will be discussed.