bluuebunny/crossref_metadata_2025 huggingface dataset:
778 PB 392 AXILLARY BUD DEVELOPMENT OF `RED SAILS' POINSETTIA IS INHIBITED BY HIGH DAY TEMPERATURES
Authors: Faust James E. , Heins Royal D.
Published: February 2019

Poor lateral branching sometimes occurs when certain poinsettia (Euphorbia pulcherrima) cultivars are pinched. Two experiments were conducted to determine the effect of high temperatures on axillary bud development. In Expt. 1, `Red Sails' plants were grown in a high-temperature environment (HTE) of 27°C at night (8 hr) and 30°C (3 hr), 33°C (10 hr), and 30°C (3 hr) in the day for two months, then transferred to a 20°C environment. In Expt. 2, plants grown at 20°C were transferred into the same HTE described above for 0, 2, 4, 8, 16, or 32 days and were then moved back into the 20°C environment. Axillary buds were examined for viability at the end of each experiment. In Expt. 1, only 8% of the lateral buds forming in the HTE were viable, while 80% of the buds forming in leaf axils of leaves unfolding after the plants were transferred to the 20°C environment were viable. In Expt. 2, 80% of buds produced in axils of the first four leaves to unfold after the start of the experiment were viable in all the treatments. However, the percentage of viable buds in the axils of leaf numbers 5 to 8 was 100, 100, 100, 96, 56, and 0 for the plants placed in the HTE for 0, 2, 4, 8, 16, and 32 days, respectively. These data indicate day temperatures of 30 to 33°C adversely affect lateral shoot development of `Red Sails' poinsettia.
782 PB 424 INVERTASE ACTIVITY AND CARBOHYDRATE COMPOSITION IN DEVELOPING ANTIRRHINUM MAJUS L. FLOWERS
Authors: Campos Ricardo , Miller William B.
Published: February 2019

The relationship between the activity of soluble acid invertase and metabolism of soluble carbohydrates was investigated in snapdragon flowers. Flowers were harvested at three different developmental stages, and at four different dates. Soluble carbohydrates were extracted and analyzed by HPLC; invertase activity was determined in crude enzyme extracts. Sucrose concentration slowly increased throughout flower development from a closed bud to a fully open flower. Fructose and glucose concentration were relatively lower at the bud stage, increased during petal elongation, then slightly decreased at flower maturity. Mannitol concentration showed little change during flower development. An unknown compound increased in concentration during petal elongation and decreased at maturity. For all harvest dates, the specific activity of acid invertase increased with flower development. These results show a positive correlation of invertase activity and hexose sugars accumulation. It is possible that at maturity sugars are metabolized at a faster rate than produced, causing a slight decline in hexose sugars.
791 PB 033 INFLUENCE OF GIBBERELLIC ACID ON SIZING OF THOMPSON SEEDLESS TABLE GRAPES IN SOUTHWEST ARIZONA
Authors: Butler Marvin D. , Rush Robert E.
Published: February 2019

Early berry maturity with adequate size and sugar is a high priority for table grape producers in the desert southwest trying to capture the early fresh market, when prices are historically at their highest. Application of gibberellic acid is used, in combination with girdling to increase berry size. Research was conducted at Valley Grapes near Dateland, AZ on 1.5 hectare unreplicated plots in 1987 and 1988, and 0.2 hectare plots replicated four times in 1989 and 1990. The influence of 120g/h, 160gh and 200g/h of gibberellic acid, applied two to three times in various combinations, was evaluated on Thompson seedless grapes. Preharvest samples provided berry weight and soluble solids data. Yield and quality were determined from the number and grade of 10 kilogram boxes harvested for each pick. Berry weight tended to increase with increased rates of gibberellic acid while yield and quality were highest for more moderate rates. Three applications generally out-performed two applications with the same, or similar, total amount of gibberellic acid.
802 PB 106 PLANT REGENERATION THROUGH SOMATIC EMBRYOGENESIS AND ORGANOGENESIS IN GRAPE ROOT STOCK CULTIVAR AXR#1
Authors: Waneck Don , Mathews H. , Stamp J. , Bestwick R.
Published: February 2019

Zygotic embryo explants of grape cultivar AXR#1 were isolated from maw-e seeds and cultured on medium supplemented with naphthoxy acetic acid beta-(NOA) and benzylaminopurine (BA). Embryo explants dedifferentiated to form embryogenic callus. Globular stage embryos were visible in 9-10 months. On transfer 10 a growth regulator free medium supplemented with charcoal these globular embryos underwent further stages of embryo development. In a period of 30-40 days embryogenic tissues turned into clumps of somatic embryos displaying different stages of development Cotyledonary stage embryos were separated and transferred to basal medium. These embryos developed into complete plants. Cold and desiccation treatment of somatic embryos significantly enhanced the rate of plant conversion. Hypocotyl segments of elongated somatic embryos were good source explant for induction of shoot organogenesis. The hypocotyl-length and the proximity to-shoot-apex were found to influence the rate of shoot induction from hypotyl segments. Multiple shoot complexes which formed on hypocotyl segments were separated and individual shoots were grown on a root induction medium resulting in complete plant development. The possibility of both embryogenic and organogenic modes of plant regeneration make somatic embryos a highly versatile explant source for experiments on genetic manipulation.
805 PB 115 FRACTAL CHARACTERIZATION OF GRAPE BERRY WAX SURFACE STRUCTURE.
Authors: Wiest Steven C , Hellman Edward W.
Published: February 2019

Scanning electron micrographs of grape berry surfaces, which resemble mountainscapes, contain a wealth of structural information. A typical statistical characterization of features such as root mean square peak-to-peak spacings, peak density, etc., is readily performed on these images. However, a much richer base of information is accessible by analyzing the images with fractal geometry. Fractal box dimension is a quantitative measure of surface roughness, and varies with the contour at which it is determined in both cultivars `Foch' and `Perlette', suggesting that the surfaces are multifractal structures. Fourier spectral analyses of the surfaces produce a similar conclusion. Thus, the unambiguous quantitative resolution of cultivars on the basis of their wax surface structure looks promising, but requires further work.
813 PB 222 A COMPARISON OF SEED RATE, SPACING, AND WEED CONTROL METHODS IN THE VIRGINIA TECH TRANSPLANTED MEADOW
Authors: Harkess Richard L. , Lyons Robert E.
Published: February 2019

Combinations of seed rate, spacing and weed control treatments were evaluated for their effect on the performance of The Virginia Tech Transplanted Meadow technique. The treatments consisted of seed rates of 112 g or 56 g per 90 m-2; within-row transplant spacing of 30, 45, or 60 cm; and mulch, oryzalin, or nothing applied for weed control. Plant competition alone was insufficient for effective weed control whereas oryzalin was the best but also reduced the plant stand and floral display. Mulch provided effective weed control with maximum floral display. Close transplant spacing within rows resulted in quick site coverage but this advantage disappeared after 8 weeks when no difference in floral display was observed. Seeding rate did not affect site coverage until the meadow reached maturity at 12 weeks. The lower seed rate allow ed more lodging, resulting in a more open appearance and greater light transmission through the canopy. Chemical name used: 4-(dipropylamino)-3,5dlnitrohenzenesulfonamide (oryzalin).
821 P8 266 EVALUATING PULP AND PAPER SLUDGE AS A SUBSTITUTE FOR PEAT MOSS IN CONTAINER MEDIA
Authors: Tripepi R.R. , George M.W. , Campbell A.G.
Published: February 2019

Pulp and paper sludge is a byproduct of paper production, yet this fibrous material may be suitable as an alternative amendment for peat moss in container media. Newsprint mill sludge was composted 6 weeks and cured before use. One-year-old seedlings of lilac (Syringa vulgaris L.) and amur maple (Acer ginnala Maxim.) as well as rooted cuttings o cistena plum Prunus × cistena Hansen) were planted in 3-liter pots that contained a barksand (2:1 by vol) mix, 25% or 50% peatamended media, or 25% or 50% sludge-amended media. After 14 weeks outdoors, shoot dry weight and changes in plant height were measured. All species planted in sludge-amended media grew as well as those potted in peat-amended media or the bark:sand mix. In fact, some species grew best in sludge-amended media. Lilac seedlings planted in 25% sludge produced almost double the amount of shoot dry weight and were 80% taller than plants in the bark:sand mix or 25% peat. Maple plants grown in 500% sludge produced over 100% or 3590 more shoot dry weight than those grown in 25% or 50% peat-amended media, respectively. Plum cuttings pottedin25910 sludge grew at least 53% taller than plants grown in either peat-amended medium. These results indicate that composted newsprint sludge can be used as a peat moss substitute in a container medium for the landscape plants tested.
825 PB 278 THE RESPONSE OF BEDDING PLANTS TO THE INCORPORATION OF HYDROGEL INTO LANDSCAPE BEDS
Authors: Boatright Jennifer L. , Zajicek J. M.
Published: February 2019

Hydrogel (Hydrosource™, Western Polyacrylamide, Inc.) was incorporated into 102 cm × 122 cm landscape beds at 25, 50, 75, or 100 lbs per 1000 sq ft. Weed barrier and 2 cm of pine bark mulch were added to the top of each bed. Controls consisted of 1) no hydrogel with weed barrier and mulch and 2) no hydrogel with mulch but no weed barrier. Each treatment was replicated four times with ten plants of petunia, marigold, and vinca planted per bed, for a total of forty plants of each species per treatment. Flower number of vinca and petunia increased with hydrogel incorporation, 75 lbs of hydrogel having the greatest number of flowers. Petunia also had higher visual ratings with increased hydrogel rates. Soil temperatures directly under the mulch and 10 cm below the mulch, at 1400 hr, were 49C and 40C respectively for controls, compared to 42C and 36C for beds with hydrogel.
826 PB 301 WATER USE OF LANDSCAPE SHRUBS SURROUNDED BY 4 DIFFERENT MULCHES
Authors: McReynolds Shelley A. , Zajicek J.M. , Mackay W.A. , Heilman J. L.
Published: February 2019

A study was conducted to explore how different mulches affect water use of landscape plants. Plots 4.9 m × 7.3 m, were covered with 5cm pine bark, cypress, white rock, or clay aggregate. 3 potted plants of Ligustrum japonicum (wax-leaf ligustrum) and Photinia × fraseri (red tip photinia) were placed in each plot so that the top of each pot was at ground level. 1 plant of each species was planted directly into each plot. Water loss was measured on a daily basis, both gravimetrically and using heat balance stem flow gauges, during both the 1992 and 1993 growing seasons. Stomatal conductance was measured periodically during each growing season. Surface, air, and soil temperatures at two depths were recorded. During 1992, pine bark mulched plants consistently used more water than the other treatments, as opposed to summer 1993 when the most water was used by plants over white rock. Surface temperatures of pine bark, cypress and clay aggregates were higher than those of white rock both years, by as much as 20C, while temperatures under the mulch varied as much as 5C between pine bark and white rock.
838 PB 358 CONTROL OF LOW-TEMPERATURE GERMINATION OF MELON (CUCUMISMELO L.) SEEDS BY SEED-COAT STRUCTURE AND OXYGEN AVAILABILITY
Authors: Edelstein M. , Nerson H. , Corbineau F. , Kigel J.
Published: February 2019

The involvement of the seed coat in low temperature germination of melon seeds was examined in two accessions differing in their ability to germinate at 14°C: `Noy Yizre'el' (NY) (a cold-sensitive cultivar) and `Persia 202' (P-202) (a cold-tolerant breeding line). Submerging the whole seed, or covering the hilum with lanolin, strongly depressed germination of NY, but not of P-202. Accessions differed in germination response to decreasing O2 concentration, with NY showing higher sensitivity to hypoxia. Intercellular spaces in the outer layer of the seed-coat were evident in the more tolerant P-202, while in the sensitive NY this layer is completely sealed. Sensitivity to hypoxia was greater at 15°C than at 25°C and was greater in NY than in P-202. It is proposed that the seed-coat imposed dormancy at low temperature in NY is the combined result of more restricted oxygen diffusion through the seed coat and a greater embryo sensitivity to hypoxia, rather than imbibition impairment or a physical constraint.
839 PB 381 EFFECTS OF ANTITRANSPIRANT AND POLYACRYLAMIDE GEL ON EARLY GROWTH OF MUSKMELON (CUCUMIS MELO L. CV. HILINE)
Authors: Daningsih Entin , Hodges Laurie , Brandle James R.
Published: February 2019

Field experiments were conducted in 1991, 1992, and 1993 to evaluate the effects of antitranspirant (Folicote, Aquatrol Inc.) and polyacrylamide gel (Supersorb, Aquatrol Inc.) on early growth of muskmelon. A RCBD with split plot arrangement was used with sheltered and exposed areas as the main treatments and seven combinations of antitranspirant spray and gel dip applications as subtreatments. Two greenhouse experiments were also conducted to simulate field research. A RCBD with seven treatments described as subtreatments in the field research was used in the greenhouse studies. Based on destructive harvests in the field, treatments and subtreatments did not affect dry weight or leaf area index. Specific contrasts, how ever, showed that gel application significantly increased dry weight and leaf area index whereas the spray application tended to reduce these factors during the first three weeks after transplanting. Significant differences between dip and spray subtreatments disappeared by five weeks after transplanting. In both greenhouse experiments, gel dip application increased dry weight and leaf area index of muskmelon at all observations from 2 weeks to five weeks after transplanting. We conclude that gel application generally will provide more benefit during early muskmelon growth compared to the use of antitranspirant spray.
841 PB 387 PHOSPHORUS RATES AND MEDIA FOR PRODUCTION OF TOMATO TRANSPLANTS USING THE FLOAT SYSTEM
Authors: Wyatt Jim E. , Akridge Marla C.
Published: February 2019

Tomato transplants were grown in plastic foam trays floated in nutrient solutions using a system adapted from tobacco transplant growers. Nutrient solutions were compared which contained equivalent amounts of nitrogen and potassium and either 35 or 70 mg·liter-1 phosphorus (P). Growing media tested were 1) Jiffy-Mix*, 2) Pro-Mix®, 3) horticultural vermiculite, or 4) perlite. The higher P rate caused increases in stem diameter, and in plant fresh and dry weight. Plant height, root dry weight and leaf area were not affected by P rate. Transplants grown in Pro-Mix® had significantly greater plant height and stem diameter than other media. Leaf area, and plant fresh and dry weight did not differ between Pro-Mix* and Jiffy-Mix@. Vermiculite and perlite produced smaller tomato transplants and should not be considered when using this production system.
CONTROLLED ATMOSPHERIC ENVIRONMENTS AND THEIR EFFECTS ON APHIDS AND WESTERN FLOWER THRIPS ON FLORAL PRODUCTS
Authors: Walter Virginia R. , Shelton Mark D. , Cavaletto Richard A.
Published: February 2019

Shipments of floral products to Pacific rim markets must meet stringent pest-free requirements. Conventional fumigation methods with methyl bromide will soon become unavailable. Studies show that controlled atmosphere (CA) environments can offer effective insect control. Currently, CA overseas marine shipping is occuring with fresh fruits and vegetables. These shipments use microprocessors to precisely control O2, CO2, temperature and relative humidity. This study is evaluating similar commercial shipments with fresh flowers and foliage under low temperature and low O2 and high CO2 atmospheres. Preliminary results with shipments conducted by TransFresh to Guam indicate that properly maintained CA shipments of 0.5 % O2 kill insects and that flowers in properly maintained atmospheres can withstand 14 days of marine shipment with minimum effect on post-harvest life. Adequate regulation of CA storage during transit seems to be the primary limitation to the expansion of floral markets using this method of shipment.
851 PB 396 THE EFFECT OF EUCALYPTUS MULCHES ON GERMINATION OF ANNUAL AND PERENNIAL WEED SPECIES
Authors: Downer A. James , Faber Ben
Published: February 2019

Eucalyptus mulch is considered by many horticulturists to be toxic to cultivated plants and weeds. The purpose of this study was to determine the weed suppressive effect of mulch made from various Eucalyptus species. Propagation flats were seeded with 100 seeds each of nine weed species and covered with peat-perlite media, or composted or fresh Eucalyptus globulus, E. citriodora, E. rudus, E. polyanthemos, E. sideroxylon, E. maculata or E. ficifolia. Fresh mulch suppressed germination of all species. Compost mulched weeds seeds germinated more and produced more dry weight than fresh mulch treatments. Barnyardgrass (Echinochloa crusgalli) died in all flats treated with fresh E. sideroxylon.
854 PB 425 CHEMICAL ROOT PRUNING OF CONTAINER-GROWN TREES USING TRIFLURALIN AND COPPER IMPREGNATED FABRIC
Authors: Newman Steven E. , Quarrels Jesse R.
Published: February 2019

Many nurseries are using the pot-in-pot (PNP) system to grow trees in containers. This system protects the roots from temperature extremes and prevents tipping. PNP is not without problems, trees with vigorous roots may escape the container and root into the external soil making harvest difficult. PNP has no effect on root circling. Our objective was to determine if a polypropylene fabric disk treated with either trifluralin or copper placed in the bottom of a container would prevent root circling. Cercis canadensis and Quercus shumardii seedlings were grown in 19 liter polyethylene containers with eight root control treatments, which included trifluralin or copper impregnated polypropylene fabric disks placed in the bottom of the containers. Ttifluralin treatments, BioBarrier and trifluralin impregnated fabric, had few roots in the bottom of the containers. Of the copper treatments, Spinout® impregnated fabric was the only copper treatment that had any effect on root development in the bottom of the containers.
864 PB 543 RESPONSE OF NIGELLIA SATIVA L. PLANTS TO FERTILIZATION AND GROWTH REGULATOR TREATMENTS. I. VEGETATIVE GROWTH AND SEED YIELD
Authors: Al-Badawy Ahmed A. , Abdalla Nadia M. , Hassan Mahmoud A. , Ali Ahmed F.
Published: February 2019

Nigellia sativa L. plants were fertilized with different rates of NPK fertilizers and sprayed with the growth regulators BL-2142 at 0, 250, 500, and 1000 ppm, CCC at 0, 500, 1000, and 1500 ppm and Multiprop at 0. 12.5, 25, and 50 ppm.

The results indicated that both of NPK fertilization and growth regulator treatments enhanced the plant growth in terms of stem diameter, branch number and herb dry weight. Also, these treatments caused early flowering, increased fruit number and seed yield compared to the control plants.

The interaction between NPK fertilization and growth regulators had a synergistic effect. The highest seed yield was obtained when the plants received 200, 100, and 25 kg/feddan (feddan = 4200 sqm) of urea, calcium superphosphate and potassium sulphate, respectively and sprayed with CCC at 500 ppm.
865 PB 544 RESPONSE OF NIGELLIA SATIVA L. PLANTS TO FERTILIZATION AND GROWTH REGULATOR TREATMENTS. II. CHEMICAL COMPOSITION
Authors: Al-Badawy Ahmed A. , Abdalla Nadia M. , Hassan Mahmoud A. , Ali Ahmed F.
Published: February 2019

Nigellia sativa L. plants were fertilized with different rates of NPK fertilizers in combination with the growth regulators, BL-2142, CCC and Multiprop sprayed at varied concentrations.

Fertilization and growth regulators increased the volatile and fixed oil content in the seeds. The photosynthetic pigments in the leaves, the reducing sugar and the total carbohydrate contents, N, P, and K uptake in the herb were also increased.

The interaction between fertilization and growth regulators had a synergistic effect on increasing the volatile and fixed oil percentage and yield, the photosynthetic pigments, N, P, K uptake. The highest volatile oil yield was found when the plants received 100, 200 and 50 kg/feddan (4,200 sqm) of urea, calcium superphosphate and potassium sulphate, respectively and sprayed with 500 ppm BL-2142, 1000 ppm CCC or 12.5 pm Multiprop. The volatile oil, fixed oil yield and seed yield were highly and significantly correlated with each other.
867 PB 546 FLOWERING RESPONSE, SEED OIL, AND VERNOLIC ACID CONTENTS OF VERNONIA GALAMENSIS INTRASPECIFIC HYBRIDS
Authors: Dierig David A. , Thompson Anson E. , Johnson Earl R. , Dahlquist Gail H.
Published: February 2019

Vernonia galamensis is a potential new crop for production of epoxidized oil with many industrial applications. This plant is native to equatorial Africa, and not adapted for culture in temperate zones since it requires a short daylength to initiate flowering and subsequent seed development. One collection of V. galamensis ssp. galamensis var. petitiana, flowered freely and produced seeds during long-day conditions throughout the United States. This variety lacks important plant characters for successful commercialization. The favorable genetic recombination of day-neutral response with more desirable plant growth characteristics, desirable seed oil and fatty acid content from other accessions of V. galamensis has been accomplished in hybrids and segregating populations, and selections are being widely evaluated throughout the U.S..
869 PB 548 THE MARKETING OF MEDICINAL PLANTS IN THE VIRGIN ISLANDS: PAST, PRESENT, AND FUTURE PROSPECTS
Authors: Thomas Toni A. , Palada Manuel C.
Published: February 2019

In the U.S. Virgin Islands (USVI) more than 400 plants are recorded as having been used for medicinal purposes. Traditional use of medicinal plants (locally known as “bush”) is based on Amerindian, African and European influences. Despite the predominance of “western medicine”, many Virgin Islanders still use medicinal plants for self-treatments, beverages and culinary purposes. Traditionally, medicinal plants were either collected growing wild or cultivated and often sold in marketplaces for local consumption. This method of marketing still exists, but new marketing outlets are developing. Selections of popular medicinal plants (imported and local) appear both fresh and packaged dry in supermarkets and specialty shops. Blended brews (i.e. “bush teas”) are available in restaurants, bakeries and delicatessens. Creatively packaged products are featured in stores and hotels catering to the tourist trade. Current expanding marketing trends target the great number of tourists visiting the USVI. Future plans with significant impact on marketing include the use of solar driers and establishment of a Fanners' Cooperative.
879 PB 267 Micropropagation of Grand Crinum Lily (Crinum asiaticum L.)
Authors: Mohamed-Yasseen Yasseen
Published: February 2019

Grand crinum Lily is an ornamental plant which is considered to be one of the architect's favorite accent. plants and one that bloom most of the year. A protocol for plant propagation from inflorescence is described. Explants were excised from inflorescence at the primordial stage. and cultured on Murashige and Skoog medium (MS: alone or supplemented with benzyladenine 4.4 or 13.3 uM benzyladenine (BA) and 0.5 uM naphthaleneacetic acid (NAA) and incubated for four weeks. Explants cultured on BA-containing media produced white flower-like structures on the receptacle which produced multiple shoots after additional four weeks on a fresh medium containing 4.4 uM BA and 0.05 uM NAA. Shoots were transferred to a fresh medium for further growth during which the basal stem reached 3 to 5 mm diameter. At this stage shoots, with or without roots, were transferred to soil, without acclimatization, and normal plants were established in soil.
880 PB 270 In Vitro Flower and Plant Formation from Opuntia dillenii Haw. and Opuntia cochenillifera Mill.
Authors: Mohamed-Yasseen Yasseen
Published: February 2019

The genus Opuntia includes a number of species which produce nutritious fruits and edible young joints, moreover, they are used as forage crop and for medicinal purposes. A procedure for flower and plant formation is described. Explants were excised from young flower receptacle and cultured on Murashige and Skoog medium (MS) supplemented with 0.9, 1.8, 4.5, or 9 uM thidiazuron and 0.5 uM naphthaleneacetic acid. Produced shoots were bisected longitudinally and cultured in a fresh medium from the same composition, other half shoots were subjected to a second cut by dividing transversely into distal and proximal explants before culture. About 80% explants of O. dellini produced flowers which produced shoots form the distal ales. only shoots were formed from O. cochenillifera explants. The distal explants produced more shoots than proximal explants. All formed shoots which attained 3 mm in length or longer were rooted directly in soil and all shoots formed roots and produced normal plants.
882 PB 276 IN VITRO PROPAGATION AND CHIMERAL TRAITS OF Cryptanthus `Marian Oppenheimer' (WIDE LEAF CLONE)
Authors: Koh Yong Cheong , Davies Fred T.
Published: February 2019

The leaves of vegetative stolons of greenhouse grown Cryptanthus `Marian Oppenheimer' (wide leaf clone) were cultured in modified MS media to induce adventitious shoot formation via callus formation. The best callus induction medium was basal MS medium with 10 μM NAA, IBA and BA. Pure green (843), maroon (3), striped (2) and albino plantlets were obtained. Most of the albino plantlets were stunted, tightly clumped together and impossible to score. The medium which produced the highest average number of non-albino plantlets was basal MS medium with 0.3 μM NAA, IBA and BA All non-albino plantlets were rooted in MS medium with 5.4 μM NAA and transplanted ex vitro with a survival rate of 96.7%. The maroon plantlets became green two weeks after transplanting. Histological studies revealed that C. `Marian Oppenheimer' (wide leaf clone) has two tunicas (L1 and L2) and a corpus (L3). Callus on the leaf explant arose mainly from the L2 and L3. Apparently C. `Marian Oppenheimer' (wide leaf clone) is a GWG periclinal chimera.
897 PB 511 ACCLIMATIZATION AND SUBSEQUENT GAS EXCHANGE, WATER RELATIONS, AND GROWTH OF MICROCULTURED APPLE SHOOTS AFTER TRANSPLANTING
Authors: Díaz Juan C , Shackel Kenneth , Sutter Ellen
Published: February 2019

Apple plantlets were cultured in a MS medium with agar and transplanted to a soilless mix. Before transplanting, plantlets were acclimatized in a chamber where humidity was linearly decreased from 99% to 75% (21 C) over a period of four days. Gas exchange measurements were made at 95% RH (21 C) and at an irradiance of 350 μmol m-2 s-1. Leaf conductance (g1) was measured with a porometer and net photosynthesis (Pn) with an IRGA. At the end of the gas exchange measurements, shoot relative water content (RWC) was determined. The results showed that plant water status was an important factor for plant survival and growth after transplanting. Acclimatization before transplanting allowed the plant to maintain a higher RWC, probably because of a better stomatal control of transpiration. Such higher water status was associated with higher growth rates in acclimatized than in non-acclimatized plants. There was a positive correlation of RWC with both a and Pn. Transplanted plants had higher values of g1 and Pn compared to in vitro plantlets. Photosynthesis of in vitro plantlets was limited by both stomatal and nonstomatal factors.
902 PB 517 CHANGES IN THE ACTIVITIES OF CATALASE, PEROXIDASE, AND SUPEROXIDE DISMUTASE DURING CHILLING STRESS IN ZUCCHINI SQUASH
Authors: Wang Chien Yi
Published: February 2019

The activities of catalase and superoxide dismutase decreased while peroxidase activity increased in zucchini squash (Cucurbita pepo L., cv. `Elite') during storage at 5°C. Preconditioning of squash at 15°C for 2 days prior to the cold storage reduced the decline of catalase activity and suppressed the increase in peroxidase activity. The superoxide dismutase activity remained higher in temperature conditioned squash than in untreated squash. These results indicate that acclimation to chilling temperature in squash may also involve modifications in the activities of catalase, peroxidase, and superoxide dismutase.
906 PB 529 FREEZING TOLERANCE AND ACCLIMATION CAPACITY INCREASED IN CULTIVATED POTATO CROSSED TO WILD POTATO SPECIES
Authors: Weiss Laurie S. , Bamberg John B. , Palta Jiwan P.
Published: February 2019

Solanum acaule (acl) and Solanum commersonii (cmm) represent the extremes of frost tolerance and cold acclimation ability among potato species. We have combined these species with cultivated S. tuberosum (tbr) to develop a potato with desired tuber traits and a high degree of frost tolerance. For this purpose diploid cmm was made 4x and crossed with naturally 4x acl. The F1 and F2 appear to exhibit hybrid vigor for vine growth for flowering, but none had frost tolerance greater than the parents. The F1 and F2 were crossed with S. tuberosum ssp. andigena and Katahdin via 2n eggs resulting in 6x 3-way hybrids. These hybrids were evaluated both in the field and laboratory for frost tolerance and acclimation ability. Results showed an increase of 1°C of frost tolerance and 2°C increase in cold acclimation capacity in the hybrids as compared to the sensitive tbr parents. Some of the 6x (3-way) hybrids produced significant tubers but yield and earliness needs much improvement. These results demonstrate that it should be possible to move both non acclimated freezing tolerance and cold acclimation ability from wild to cultivated species and offer exciting opportunities to enhance potato production in frost prone areas in the world.

Supported by USDA/NRI grant 91-3700-6636 to J.P.P. and J.B.B..
IMAGING SPECTROMETER AND ITS APPLICATION TO PLANT STRESS PHYSIOLOGY
Authors: Li Ning , Daley Larry S.
Published: February 2019

The goal of our project is to develop a non-invasive means to monitor the physiological status of plants. Spectral image acquisition is a powerful analytical approach for determining chemically distinct species in heterogeneous materials. It was found by Callis and Brukner that the combination of a continuously tunable monochromatic light with a thermoelectric-cooled CCD detector offered the best approach. In the in vivo spectra of leaf, researches has been focused on interpreting the visible spectra in terms of the profile of various types of chlorophyll-protein complexes and relating these to selected aspects of plant pathology and physiology. A computer interfaced imaging spectrometer employing a CCD detector was constructed. It can record the transmitted spectra of up to 31,680 positions for each sample. The instrument was used to study in vivo spectra of sugar cane and barley leaves. The light harvesting complex proteins were then `interpreted from the spectra and were shown graphically. Excellent results were also obtained when we measured the relative respiration rate of plant roots. A pH sensitive dye Resazurin was used to show the pH changes around a soybean root. The spectral images changing as a function of time were recorded and the relative respiration rate of any position of the root could be determined.
912 PB 156 EFFECT OF SOIL STERILIZATION WITH METHYL BROMIDE GAS ON GROWTH AND PRODUCTION OF STRAWBERRY (Fragana × ananassa) Duch
Authors: Ragab M. I. , Okasha Kh. A.
Published: February 2019

The objective of thus work was to study the effect of soil fumigation with methyl bromide and different mulching types on growth and productivity of the strawberry cultivar Chandler. The experiment Included 8 Treatments which were the combination of 2 soil fumigation treatments × 4 mulching polyethylene types A split plot design with four replicates was adopted Soil fumigation treatments (fumigated and non fumigated) were assigned as main plots, whereas the four mulching polyethylene treatment (control, black, white and transparent) were distributed as subplots.

Results Indicated that in order to improve the vegetable growth and to increase the high yielding ability of strawberry cv. Chandler, it is recommended to fumigate soil with methyl bromide gas (50 gm/m2) and apply transparent polyethylene soil mulching

Moreover, in strawberry fields where weeds show serious problem. it is better to use the black polyethylene in controlling weeds of both the fumigated and non fumigated soils.
914 PB 182 INDUSTRY/UNIVERSITY COMMITMENTS SPARK RESEARCH AND EXTENSION EFFORTS ON STRAWBERRY IN FLORIDA
Authors: Chandler Craig K. , Crocker T. E. , Albregts E. E.
Published: February 2019

During the past 10 years, the Florida strawberry growers, through the Florida Strawberry Growers Association, have made a serious commitment to fund university research on strawberries. They have purchased equipment and donated monies for facilities at Dover. They have also helped support a new faculty position in breeding and genetics. During this same period, the University of Florida has made an equally strong commitment to support strawberry research and extension. These commitments are beginning to pay significant dividends for industry and the University. Cultural and pest management information has been generated that is saving the industy money, and the breeding program is developing new cultivars that will keep the industry competitive in the marketplace. The University has benefitted through the acquisition of new facilities, equipment, and faculty and graduate student support.
918 PB 194 EFFECT OF FLORICANE NUMBER AND PRIMOCANE PRUNING ON PRIMOCANE GROWTH IN `MARION' BLACKBERRY
Authors: Cortell Jessica M. , Strik Bernadine C.
Published: February 2019

Treatments consisting of 0, 4, 8, or 12 floricanes were established in March 1993. An additional treatment was set up with zero floricanes and early primocane pruning. Starting in April and continuing through early November, weekly primocane measurements were taken including: number of nodes, number of primocanes, number of branch canes, length of primocanes, and length of branch canes. Additional plants in each treatment were harvested in August to assess total biomass partitioning. The zero floricane treatment had a significant increase in the number and length of both primocanes and branches. Primocanes grown without competition from floricanes had a 65 % increase in primocane dry weight. Primocane pruning resulted in significantly shorter internodes, an increase in branch dry weight, and a decrease in total length of the primocanes. The increase in total primocane biomass with removal of the floricanes should contribute to higher yields the following season.
928 PB 503 ANTIOXIDANT ACTIVITY AND TOTAL PHENOLIC CONTENT IN DIFFERENT GENOTYPES OF POTATO (SOLANUM TUBEROSUM)
Authors: Al-Saikhan Mohamed S. , Howard Luke R. , Miller J. Creighton
Published: February 2019

Two varieties of yellow flesh (Granola and Yukon Gold) and two white flesh (Viking and Russet Norkotah) potatoes were grown near Springlake, Texas in the summer of 1992. Varieties were investigated for their antioxidant activity and total phenolic content. Varieties were significantly different in antioxidant activity and total phenolic content (P = 0.0001). Granola had the highest antioxidant activity and Russet Norkotah the highest total phenolic content, while Yukon Gold had the lowest antioxidant activity and total phenolic content. Further study was conducted on tuber parts (distal end, center, and stem end) and among sections within each tuber part. Differences were slight among tuber parts in antioxidant activity, but significant in total phenolic content. Moreover, the differences were slight among the three sections for antioxidant activity and total phenolic content, while the fourth section containing the skin (epidermal tissue) had the highest antioxidant activity and total phenolic content.
947 SCREENING MARIGOLD CULTIVARS FOR SUSCEPTIBILITY TO IRON TOXICITY
Authors: Todd Nancy K.
Published: February 2019

Marigolds are susceptible to a specific nutritional disorder known as “bronze speckling”. It has been reported that the disorder is caused by excessive uptake of iron by the plant, which may be due to high levels of Fe in the soil solution or low soil pH. In this experiment, 12 cultivars of marigold (Tagetes erecta and T. patula) were grown using increasing levels of Fe (0, 5, 15, and 20 mg/l) from Fe DTPA. In the susceptible cultivars, symptoms were observed within 5 days of initial treatment and appeared as a chlorotic mottling. Initial symptoms resembled spider mite damage on older leaves, which gradually became bronze colored in appearance, and finally became necrotic. Downward cupping of leaves was observed in severely affected plants. Severity of necrosis and percent of plant leaves affected (dry weight basis) were evaluated to determine susceptibility of the different cultivars to the disorder. There was a direct correlation between increasing concentration of Fe and occurrence and severity of symptoms. The most susceptible to least susceptible cultivars were determined to be: First Lady, Inca, Discovery, Galore, Pineapple Crush, Perfection Excel, Voyager All Seasons, Nugget, Zenith, Voyager F1 and Diamond Jubilee.
955 PB 455 EVALUATION OF WINTER PROTECTION STRATEGIES FOR RED RASPBERRY CANES
Authors: Badertscher Kerrie B. , Hughes Harrison G.
Published: February 2019

Renewed interest in red raspberry production in Colorado has been limited by winter kill of canes. Winter kill in Colorado may be the result of extreme cold temperatures, desiccation, or a combination of the two. We are evaluating winter protection strategies to increase survival and to better understand the winter stress of raspberries. The four (4) cane treatments of red raspberry, Rubus ideaus L. cv. Heritage, used were (1) canes bent and wrapped with plastic; (2) canes bent and mulched with hay and soil; (3) canes upright with anti-desiccant spray; (4) a control of canes upright without protection. Moisture content and electrolyte leakage were evaluated at intervals. Relative moisture loss was greatest in the control as compared to the other treatments. The terminal sections of the canes exhibited greater moisture loss as compared to basal sections in the control with a similar trend in the other treatments. Relative survival as indicated by electrolyte leakage was monitored and will be correlated with moisture loss.
1004 THE DUAL ROLE OF MANNITOL AS OSMOPROTECTANT AND PHOTOASSIMILATE IN CELERY
Authors: Pharr D.M. , Stoop J.M.H. , Feusi M.E. Studer , Williamson J.D. , Massel M.O. , Conkling M.A.
Published: February 2019

Mannitol, a six carbon sugar alcohol, is widely distributed in nature and is a major phloem-translocated photoassimilate in celery. II may also function as a compatible osmolyte providing stress tolerance. Until recently, little was known about the route of mannitol catabolism in sink tissues of higher plants. An enzyme. mannitol dehydrogenase. (MDH) that oxidizes mannitol to mannose utilizing NAD as the electron acceptor was discovered (Arch. Biochem. Biophys. 1991. 298:612-619) in “sink” tissues of celery and celeriac plants. The activity of the enzyme is inversely related to tissue mannitol concentration in various parts of celery plants suggesting a role for the enzyme in mannitol catabolism. In osmostressed celery plants, the activity of the enzyme in sink tissues decreases as mannitol accumulates.

Celery cells growing heterotrophically in suspension culture utilize either sucrose or mannitol as the sole carbon source and grow equally well on either carbohydrate. Mannitol-grown cells contain more MDI-I activity than sucrose-grown cells, and the activity of the enzyme is correlated with the rate of depletion of mannitol from the culture medium. Cells growing on mannitol contain an internal pool of mannitol but little sugar. Cells growing on sucrose contain internal sugar pools but no mannitol. Mannitol-grown cells are also more salt tolerant than cells grown on sucrose. Our laboratory is involved in studies of the physiological role of the mannitol oxidizing enzyme in regulating mannitol utilization and the role of the enzyme in regulating mannitol pool size during salt and osmostress in both celery plants and celery suspension cultures. Current studies on the molecular control of expression of the enzyme will be discussed.
1008 ANTHOCYANIN BIOSYNTHETIC GENES AND THEIR APPLICATION FOR FLOWER COLOR MODIFICATION
Authors: Courtney-Gutterson Neal
Published: February 2019

The biosynthetic pathway for anthocyanins has been studied using genetic, biochemical and molecular biological tools. In the past decade, the core pathway genes have been cloned; a number of genes which act to modify anthocyanin structure have been cloned more recently. The first results in color modification have been reduced flower color intensity using gene suppression methods. In particular, we have utilized chalcone synthase (CHS) and dihydroflavonol reductase (DFR) genes and sense suppression in our experimental system, Petunia hybrida, and in the commercial crops, chrysan-themum (Dendranthema morifolium) and rose (Rosa hybrida). In petunia a range of new phenotypes was obtained; genetic stability of suppressed pheno-types will be described. In chrysanthemum a white-flowering derivative of a pink-flowering variety will be described. In rose uniform, partial reduction in pigment intensity throughout the flower was observed in over a dozen trans-genie derivatives of a red-flowering variety.
1023 MANAGING BORON NUTRITION IN DECIDUOUS TREE FRUIT ORCHARDS
Authors: Peryea Frank J.
Published: February 2019

Boron (B) is an essential micronutrient that is often in inadequate supply in many deciduous tree fruit orchards and must therefore be added as fertilizer. It can also occur at phytotoxic levels because of over-fertilization, use of high-B irrigation water, or naturally in arid soils that are natively high in B. Tree B status is usually characterized by leaf analysis although other diagnostic criteria are being evaluated. Several tests are used to characterize soil B status. Symptoms of B deficiency include blossom blast, poor fruit set and development, shortened internodes, terminal bud death, and shoot dieback. To ameliorate deficiency, B fertilizer may be broadcast or sprayed over the soil surface or sprayed on tree canopies. In some regions, maintenance applications of B fertilizer are made to prevent development of B deficiency. Sodium borates or orthoboric acid are usually used. Fertilizer rates and timing vary with location and farming practices. Symptoms of B excess include reduced or no yield, impaired fruit quality, leaf marginal chlorosis and necrosis, defoliation, and shoot dieback. Boron toxicity is alleviated by leaching B-enriched soil to move B below the root zone.
1024 FERTIGATION IN CITRUS ORCHARDS: A PROMISE OF MORE EFFICIENT AND ENVIRONMENTALLY SOUND FERTILIZATION
Authors: Swietlik Dariusz
Published: February 2019

The public is increasingly concerned with the danger of ground water pollution with fertilizer nitrogen and other chemicals. This is because slow water movement in underground aquifers assures the long lasting existence of contaminants. Citrus orchards commonly are heavily fertilized with nitrogen and other mineral nutrients. Fertigation through a low volume irrigation system is a promising new method of efficient use of fertilizer materials because it places mineral nutrients only in the wetted zones where roots are most active. Preliminary studies in Texas indicate that applying nitrogen fertilizers through a low volume irrigation system is a potentially powerful tool in minimizing N fertilizer leaching. When coupled with partial sodding in close tree proximity further reductions in NO3 leaching may be achieved presumably through uptake into the cover plants and/or indirectly by enhancing biological fixation in the soil. Other potential benefits of frequent N fertigations in citrus orchards will also be discussed based on the experimental data collected in various parts of the world.
1031 EFFECT OF COMMERCIAL HUMIC ACIDS ON MICRONUTRIENT UPTAKE BY VEGETABLES
Authors: Hernández Eovaldo
Published: February 2019

Most of the studies on the effect of humic acids on micronutrient uptake by plants has been carried out in nutrient solutions. Commercial companies have tried, without adequate experimental support, to extend the conclusions of these studies to the production of vegetables in agricultural soils. The effect of humic acids on micronutrient uptake by plants has been attributed' to (a) the improved supply of micronutrients to the soil solution caused by a higher rate of release from soil minerals (probably via chelate formation by humic acids) and (b) the improved uptake of micronutrients as consequence of the larger root system promoted by hormonal compounds in the humic acids. In soils with limiting concentration of micronutrients (such as some calcareous soils) and low content of organic matter, chelation of micronutrients by added commercial humic acids might increase their availability to plants. However, in agricultural soils with and adequate content of organic matter, no significant effect of commercial humic acids on micronutrient uptake by plants can be detected.
1045 IMPACT OF SEED VIGOR ON PRODUCTIVITY OF VEGETABLE TRANSPLANT NURSERIES AND MECHANICAL TRANSPLANTING OPERATIONS.
Authors: Adams Steven C.
Published: February 2019

Seed vigor has a very subtle effect on the productivity of greenhouses producing vegetable transplants, celery, cauliflower, lettuce, etc. and on todays highly mechanized automatic or semi-automatic transplanting operations. As greenhouse production technology moves from traditional bare root to plug/tray growing systems and as automatic and semi-automatic transplanting operations increase in number, the impact of poor seed vigor is realized.

Measures to mitigate the impact of poor seed vigor in the nursery are: Seed density grading; increased growing cycle in the nursery, hand culling or replanting. Measures to mitigate the impact of poor seed vigor in automatic transplanting operations: increase the number of people following the planter to replace poor vigor plants; use hand fed transplanters.
1058 IMPROVING CROP MANAGEMENT SYSTEMS FOR THE PRODUCTION OF CULINARY HERBS IN THE VIRGIN ISLANDS
Authors: Palada Manuel C. , Crossm Stafford M.A.
Published: February 2019

The Caribbean region is one major source of most herbs and spices consumed in the U.S. Although the U.S. Virgin Islands (USVI) is part of the Caribbean, local production of herbs and spices does not contribute significantly to exports into the U.S. market. Nevertheless, culinary herbs area” important horticultural crop in the USVI and their sale provides income for many small-scale growers. Little research has been done to improve field production in the USVI. Inefficient cultural practices used by growers result in low yields. Lack of information on fertilizer rates, irrigation and pest control methods is a major constraint to high yields. In 1988, the Agricultural Experiment Station initiated a project to improve field production of herbs and spices in the USVI. Use of drip irrigation, mulching and fertilizers has improved yields of basil (Ocimum basilicum) and thyme (Thymus vulgaris). This paper will discuss crop management studies to improve culinary herb production in the USVI. Increasing production may help reduce U.S. imports of these specialty crops from other Caribbean island nations.