bluuebunny/crossref_metadata_2025 huggingface dataset:
Micropropagation of Helleborus orientalis Lam. and Aconitum uncinatum Linn. (Ranunulaceae)
Authors: Lim C.C. , Kitto S.L.
Published: February 2019

The objectives of this study were to develop systems for mass proliferation, rooting, and reestablishment of microcuttings of Helleborus orientalis and Aconitum uncinatum. Basal medium for H. orientalis contained 1/2 MS with 0.4 mg thiamine–HCl/liter, 0.5 mg pyridoxine–HCI/liter, 0.5 mg nicotinic acid/liter, 100 mg i-inositol/liter, 5 mg BA/liter, 2% sucrose, and 0.7% Phytagar. There was no effect of GA (1 mg–liter–1) or TDZ (0.1, 1 mg–liter–1) on axillary shoot proliferation. Helleborus orientalis rooted in vermiculite, Redi-Earth, or 4 perlite: 1 peat with 50% to 56% survival. A field plot containing 18 clonal H. orientalis has been established. Basal medium for A. uncinatum contained WPM with 2% sucrose, 2.5 mg BA/liter, 150 ppm ascorbic acid, 150 ppm citric acid, and 0.7% Phytagar. There was no effect of photoperiod (8, 12, 14 h, 52.5 μmol–m–2–s–1 photosynthetic active radiation) or banana extract on axillary shoot proliferation. Significantly more axillary shoots were generated in the presence of BA (10 mg–liter–1) + kinetin (10 mg–liter–1). Medium containing 500 ppm of PVPP resolved blackening of microcutting bases. More than 500 in vitro-rooted microcuttings (1 mg IBA/liter) survived and grew when transplanted into MetroMix 510 and placed under humidity domes for 6 weeks in the mist.
The Mass Production and Acclimatization of Somatic Embryos in Oenanthe stolonifera DC.
Authors: Namkung Yong , Lee Byoung Yil
Published: February 2019

Immature florets were inoculated on MS basal salt media (3% sucrose + 0.8% agar) + 1.0 mg 2,4-D/liter to induce embryogenic callus. Induced embryogenic callus was sieved through serial metal mesh screens (40 and 60 mesh) and placed on the embryo induction media at different concentrations of cytokinins and osmotica. BAP (0.1 mg–liter–1) or TDZ (0.001, 0.01, 0.1, and 1.0 mg–liter–1) were treated on 1/2 MS (3% sucrose) according to the following schedules: 1) first 2 weeks of treatments, followed by 3 weeks of 1/2 MS (3% sucrose) (FT); 2) first 3 weeks of 1/2 MS (3% sucrose), followed by 2 weeks of treatment (LT); and 3) 5 weeks of treatments. PEG, mannitol (0, 2.5%, 5.0%, 7.5%, and 10.0%), and sucrose (0%, 3%, 6%, 9%, and 15%) also were used as osmotica with ABA (0.05 mg–liter–1), respectively. The treatment schedules were FT and LT. Several good quality embryos were produced at 0.001 mg TDZ/liter, 0.1 mg BAP/liter, or 7.5% and 10.0% PEG (only FT). Abnormal embryos were significantly reduced at 7.5% and 10.0% PEG. Leaves of the plants obtained through somatic embryos were compared with those of seed-propagated plants before and after acclimatization using SEM. Epidermal and conductive tissues developed little in the plants before acclimatization; however, they developed gradually after acclimatization and were similar to those of seed-propagated plants.
Effect of Irradiance Level and Iron Chelate Source on the Shoottip Culture of Carica papaya L.
Authors: Castillo B. , Madhavi D.L. , Smith M.A.L.
Published: February 2019

Interaction between irradiance levels (5–40 mM–m–2–s–1) and iron chelate sources (FeNa2EDTA and FeNaDTPA) on the establishment, growth, and proliferation of shoot tips of Carica papaya were tested. Reduced irradiance level (5 mM–m–2–s–1) enhanced the establishment of shoot tips regardless of the source of iron chelate tested. At higher irradiance levels (30 and 40 mM–m–2–s–1), presence of FeNaDTPA in the medium enhanced establishment of shoot tips. Continuous or alternating light/dark (16/8 h) photoperiods at high irradiance levels had no effect on the establishment or growth of the culture. At higher irradiance levels, the cultures produced smaller leaves as compared to lower irradiance levels. Low irradiance and FeNa2EDTA was preferred during the proliferation stage.
Validation of Boxwood Cultivars by Biochemical Markers
Authors: Marquard Robert D. , Chan Charlotte R. , Davis Eric P.
Published: February 2019

Leaf tissue from 10 Buxus spp. cultivars were collected and evaluated for differences in isozyme and random amplified polymorphic DNA (RAPD) markers. In addition, samples of named cultivars were collected from multiple locations to estimate the degree of cultivar fidelity across locations. In general, isozymes were highly polymorphic among cultivars. Aconitase, malate dehydrogenase, aminoaspartate transferase, and phosphoglucose isomerase were the most useful isozymes to distinguish among the selected clones. Good quality DNA was readily extracted from leaf tissue using a standard CTAB procedure. RAPDs were generated from polymerase chain reactions using a random set of primers. Of 200 primers that were screened, 20 gave reproducible and polymorphic patterns that could be used to distinguish among the boxwood cultivars. In general, cultivar fidelity among commercial nurseries was fair. Biochemical analyses could be used to resolve problems with cultivar identity once baseline information is collected.
Accelerated Test of Paper Mulch Degradation
Authors: Stewart K.A. , Jenni S. , Martin K.A.
Published: February 2019

In 1994, field trials were undertaken to evaluate the agronomic performance of a range of paper mulches in vegetable production. During the course of the experiments, the majority of the paper mulches tested degraded part way through the growing season. Before the next growing season, a range of Kraft papers differing in densities and compositions were subjected to an accelerated degradation test to determine which mulches would be suitable for use under Quebec field conditions. A mixture of equal parts black soil, sand, and manure (two parts sheep manure and one part liquid cow manure) was placed into trays of 26 x 52 cm. Experimental papers were cut into strips measuring 2.5 x l.5 cm and put into the trays such that half of the strips were covered with the mixture. The trays were placed in a growth cabinet (30C with a relative humidity of 50%). Three replicates of each treatment were sampled 3, 5, 7, 11, and 14 days after placement to determined the amount of degradation that had taken place. It was found that the length of time taken for degradation in the accelerated system was 3.7 times less than that of the field.
The Advances in the Study on Mycorrhizas of Fruit Trees in China
Authors: Runjin Liu , Kun Xu , Pengqi Liu
Published: February 2019

The study of mycorrhizas of fruit trees was carried out in the 1980s in China. More progress has been made in resources, taxonomy, anatomy and morphology, physiology, ecology, effects, and application of mycorrhizas in fruit trees. The present status and research trends in the study of fruit tree mycorrhizas in China were introduced, and the application prospects of mycorrhizas in fruit tree cultivation also were discussed.
Peroxidase, Polyphenoloxidase, and Superoxide Dismutase Activities in Relation to Apple Fruit Development, Ripening, and Storage
Authors: Abbasi Nadeem A. , Kushad Mosbah M.
Published: February 2019

Peroxidase (POD), polyphenoloxidase (PPO), and superoxide dismutase (SOD) activities were measured during several phases of bud development, ripening, and storage of `Oregon Spur Red Delicious' (Malus domestica Borkh) apple fruit. POD, PPO, and SOD activities were significantly altered as a result of bud development. At the early stages of fruit development, the activities of these enzymes were significantly higher, then declined as the fruit increased in size. The activities of these enzymes declined as the fruit reached full maturity. Fruits harvested 3 weeks before commercial maturity and stored for up to 6 months have higher enzyme activities than fruits harvested at or beyond commercial maturity. The activities of these enzymes in relation to fruit firmness, soluble solids, and ethylene will be determined and related to overall fruit quality.
WinRHlZO™, a Root-measuring System with a Unique Overlap Correction Method
Authors: Arsenault J.-L. , Poulcur S. , Messier C. , Guay R.
Published: February 2019

WinRHlZO™ is a new root measuring system (1993) based on an optical scanner instead of a video camera. Scanners produce high-quality images, free of illumination problems, over large areas (typically 11 × 17 inches). They are also extremely easy to use, and do not need to be recalibrated each time the optical set up or the resolution is changed. Different lighting systems are also available. WinRHlZO™ is an interactive system; the user can see on screen with color codes what the system is measuring and can make corrections if needed. WinRHlZO™ has the capacity to detect overlapping root parts and to compensate for them in the final results. It measures total length, projected area, surface area, and root length for different width intervals chosen by the user. The results are shown in a printable histogram placed above the image. The system also counts root tips and branching points. It is possible to verify the width at different points along the root by clicking them in the image. WinRHlZO™ can analyze whole images or different parts of them. It runs on IBM-compatible software under Microsoft Windows 3.1 or NT, and on Macintosh computers.
Relationship between Texture and Cell Wall Polysaccharides of Fruit Flesh in Various Species of Citrus
Authors: Muramatsu Noboru , Takahara Toshio , Kojima Kiyohide , Ogata Tatsushi
Published: February 2019

Various species and cultivars of citrus were studied to determine the relationship between texture and cell wall polysaccharide content of fruit flesh. Among those tested cultivars, navel orange (Citrus sinensis Osbeck) and hassaku (C. hassaku Hort. ex Tanaka) were firmest, `Fukuhara orange' (C. sinensis Osbeck) was intermediate, and satsuma mandarin (C. unshiu Marc.) was softest. There was a 3-fold difference in firmness among the 12 citrus cultigens measured. Cohesiveness values ranged from 0.30 to 0.49 and were not correlated with fruit firmness. Sugar content in each cell wall fraction was highest in the water and EDTA fractions, followed by the hemicellulose fraction, and was lowest in the cellulose fraction. Correlation coefficients between firmness and sugar content ranged from 0.69 to 0.88 and were highest in the cellulose fraction. This study suggests that firmness of fruit flesh among the cultigens is influenced by cell wall polysaccharide composition. Chemical name used: ethylenediaminetetraacetic acid (EDTA).
Isozymes and Canonical Discriminant Analysis to Identify Pistachio (Pistacia vera L.) Germplasm
Authors: Barone Ettore , Di Marco Luigi , Marra Francesco P. , Sidari Maria
Published: February 2019

Canonical discriminant analysis (CDA) of morphometric data of buds, leaves, and fruit, as well as isozyme analysis (esterase, peroxydase, and acid phosphatase) of leaf samples, were used to identify eight male pistachio selections and 10 female pistachio cultivars. According to the CDA, 77% and 93% of the total variance was summarized by the first three canonical discriminant functions for the female and male selections, respectively. Fruit characteristics, particularly fruit fresh and dry weights and fruit length, accounted for most of the discriminatory power for the female cultivars, while the dimensions of the leaves, principally leaf rachis length, were the most effective discriminating characters for the males. Isozyme analysis showed a higher degree of polymorphism in the male than the female genetic pool. Hence, using only three enzymes, it was possible to identify all of the male selections, but only 50% of the females. Peroxidase polymorphism clearly demonstrated the greater phylogenetic distance between `Kerman' and the local cultivars, as well as between `Cerasola', a quite different cultivar with a reddish hull, and the others tested. The combination of CDA and isozyme analysis enhanced the possibility of uniquely identifying the female cultivars.
Dry-matter and Nitrogen Yields of Legumes Interseeded into Sweet Corn
Authors: Guldan Steven J. , Martin Charles A. , Cueto-Wong Jose , Steiner Robert L.
Published: February 2019

Five legumes [hairy vetch (Vicia villosa Roth.), barrel medic (Medicago truncatula Gaerth.), alfalfa (Medicago sativa L.), black lentil (Lens culinaris Medik.), and red clover (Trifolium pratense L.)] were interseeded into sweet corn (Zea mays L.) at last cultivation when sweet corn was at about the V9 (early) or blister (late) stage. The effect of legume interseeding on sweet corn yield, and late-season dry-matter and N yields of aboveground portions of the legumes was determined. Sweet corn yield was not affected by legume interseeding. In 1993, legume dry-matter yields were 1420 kg·ha–1 interseeded early and 852 kg·ha–1 interseeded late. Nitrogen yields were 49 kg·ha–1 interseeded early and 33 kg·ha–1 interseeded late. In 1994, dry-matter yields were 2760 kg·ha–1 interseeded early and 1600 kg·ha–1 interseeded late. Nitrogen yields were 83 kg·ha–1 interseeded early and 50 kg·ha–1 interseeded late. In 1993, barrel medic was the highest-yielding legume with dry matter at 2420 kg·ha–1 and N at 72 kg·ha–1 interseeded early, while red clover yielded the lowest with dry matter at 340 kg·ha–1 and N at 12 kg·ha–1 interseeded late. In 1994, dry-matter and N yields ranged from 4500 and 131 kg·ha–1, respectively, for early interseeded barrel medic to 594 kg·ha–1 and 16 kg·ha–1, respectively, for late interseeded red clover.
Petaloid Male-sterile Plants from Carrot Cell Cultures
Authors: Wright Jolene , Reilley Ann , Labriola Jean , Kut Stephanie , Orton Thomas
Published: February 2019

An experiment was conducted to determine the types, extent, and heritability of new phenotypic variants recovered from carrot cell cultures initiated from mature tap-root explants of the male-fertile carrot (Daucus carota L.) `Slendero'. Embryogenic callus was transferred to plant-growth-regulator-free medium 66 days after culture initiation, and regenerated plantlets were harvested and eventually planted in a field. The tap roots of mature regenerated plants were vernalized at 5C for 9 weeks and replanted. Of 31 flowering regenerants, 25 exhibited some form of petaloid male sterility; the remaining six regenerants were male fertile. All plants from the same original explant were either all sterile or all fertile. Three generations of sterile regenerant × petaloid cytoplasmic male sterility (CMS) maintainer (M) progeny tests showed that the new CMS behaved in a similar manner to that previously reported. Comparison of mitochondrial DNA restriction patterns of sterile and fertile regenerants with those of `Slendero', petaloid CMS, petaloid M, and brown anther CMS lines resulted in the following conclusions: 1) the sterile regenerants exhibited patterns identical to the known petaloid CMS and 2) the fertile regenerants were different from the original `Slendero' and the sterile regenerants and nearly identical to a known petaloid CMS M line. The high frequency of CMS among regenerants from `Slendero' carrot cell cultures may provide an efficient method to develop sterile M tandem lines and corresponding new hybrid varieties.
Inheritance of Specific Flower Colors in Petunia hybrida
Authors: Griesbach R.J.
Published: February 2019

The biochemistry of flowers is very complex, depending not only on the specific anthocyanin present but also on vacuolar pH, presence of metal ions, type of co-pigment present, and the molar ratio of co-pigment to anthocyanin. Because of the wide array of different flower colors, Petunia hybrida is an excellent model system to study the genetic interaction of all of these factors. The segregation of the different flower colors in an F2 population from a red × violet outcross could be explained through the combined inheritance of anthocyanin pigmentation and pH. The inheritance of anthocyanin pigmentation was controlled by two independent genes (hf and Mf) that followed simple Mendelian genetics. The inheritance of pH was more complex, being controlled by two independent co-dominant genes (Ph1 and Ph2). Linkage of the various pH and anthocyanin genes prevented the expression of all of the potential gene combinations.
Water Use and Crop Coefficients of Woody Ornamentals in Containers
Authors: Schuch U.K. , Burger D.W.
Published: February 2019

Twelve species of woody ornamental plants were grown for 2 years in containers at Riverside and Davis, Calif., to determine plant water use (WU) and compare crop coefficients (Kcs). WU was determined gravimetrically in 1993 and 1994, five times each year in Riverside and four times each year in Davis. WU and Kc were affected by significant interactions among species, location, and time of year. WU was primarily influenced by the month, while Kc was most affected by location. Rhaphiolepis and Pittosporum, followed by Juniperus and Photinia, respectively, were the highest water users in Riverside when averaged over the 2 years. Arctostaphylos was the highest water user in Davis, followed by Juniperus, Cercis, and Pittosporum, respectively. Rhamnus, Prunus, and Cercocarpus were among the lowest water users in both locations. Heteromeles, Buxus, and Ceanothus were intermediate water users. The largest difference in species WU between the two locations was found for Arctostaphylos and Cercis, both high water users in Davis, but moderate or low water users in Riverside. The other species ranked similarly in both locations. Kcs of the 12 species, when averaged over the 2-year sampling period, ranked similar to water use. Kcs tended to be artificially high in the winter months and were not correlated to the low WU during that time.
Effects of Irrigation Rate and Frequency on Young Citrus Tree Performance and Root Distribution
Authors: Parsons Larry R. , Wheaton T. Adair
Published: February 2019

Hamlin orange trees on Swingle rootstock planted in 1991 were subjected to six different rates of irrigation with approximately the same amounts of water applied either daily (1-day), every other day (2-day), or every 4th day (4-day). Rates provided from 0.43 to 1.95 of historical daily evapotranspiration (ET) applied to the wetted area. Irrigation was delayed following rainfall. The effects of irrigation rate and frequency on trunk and canopy growth, yield, soil water content, root distribution, and total water use were studied. There was little effect of irrigation rate or frequency during the first 2 years after planting. However, tree growth improved with increasing irrigation rate during the 3rd and 4th years, and growth in these years was greater when irrigation was scheduled daily. Effects of rate and frequency on growth were not as great as expected. Yield increased as irrigation increased in 1994. Leaf nitrogen was generally higher at the lower irrigation rate. Soil water content varied with depth. Extraction of soil water was more rapid in the top 45 cm of soil. Roots after 4 years did not extend below 45 cm with 60% of the roots in the top 15 cm and 90% in the top 30 cm. Roots were concentrated closer to the trunk for trees at the lower irrigation rates.
Early Nodulin Gene (ENOD2) Expression in Maackia amurensis Rupr. & Maxim. (Amur maackia)
Authors: Foster Carol M. , Graves William R. , Horner Harry T.
Published: February 2019

A complete picture of legume nodulation has yet to be elucidated. Most studies of the molecular mechanisms responsible for nodule organogenesis have focused on herbaceous legumes. We investigated the presence of a putative ENOD2 gene and studied the temporal and organ-specific production of its transcripts in an ornamental woody legume, Amur maackia. Primers derived from proline-rich pentapeptide repeats of conserved ENOD2 sequences and the genomic DNA of Amur maackia were used to obtain a 543-bp PCR fragment. Southern and Northern blots were probed with this cloned fragment. The Amur maackia genome contained an ENOD2 sequence that is similar to sequences in other species. Expression of the putative ENOD2 gene was detected in roots, 4 days after rhizobial inoculation, but not in leaves or stems. New data on the characteristics of nodulin genes in woody legumes will be beneficial in clarifying the nature and evolution of nodulation in legumes and may have implications for developing sustainable nursery production protocols.
Cold Storage and Harvest Date Modifies the Ethylene Requirement for Kiwifruit Ripening.
Authors: Ritenour Mark A. , Crisosto Carlos H. , Cheng Guiwen W. , Garner David T.
Published: February 2019

The development of ethylene preconditioning treatments for kiwifruit have made it possible to deliver ripe kiwifruit to consumers early in the season. We report on how maturity and length of storage time affect the ripening responses of kiwifruit [Actinidia deliciosa (A Chev) Liang et Ferguson cv Hayward] preconditioned with 100 ppm ethylene at 0°C for 24 hours and ripened for 10 days at 20°C. Kiwifruit freshly harvested at weekly intervals continued to soften faster in response to ethylene preconditioning compared to air controls for at least 5 weeks following commercial harvest. In contrast, kiwifruit commercially harvested and stored at 0°C for more than 2 weeks no longer responded to low-temperature ethylene preconditioning. However, kiwifruit stored more that 5 weeks were still responsive to exogenous ethylene and softened faster when exposed to continuous ethylene at either 0 or 20°C. Kiwifruit had relatively high respiration rates 1 days after transferring from 0 to 20°C, which quickly dropped to base levels within 1 day. Fruit stored >1 week at 0°C always had higher initial respiration than freshly harvested fruit on transfer to 20°C, and ethylene preconditioning increased initial respiration of freshly harvested fruit but had less of an effect on initial respiration of stored fruit. Plotting firmness against individual fruit's respiration and ethylene production revealed a distinct rise in respiration and ethylene production only after fruit softened to <6.5 N. Preconditioning fruit at 0°C did not significantly alter the timing of the climacteric respiration or ethylene peaks.
Postharvest Factors Affecting Quality of Butternut Squash during Storage
Authors: Manseka Vuvu D. , Hicks James R.
Published: February 2019

Butternut squash was harvested at two stages of maturity in 1994 and was cured for 10 days at 26°C and 80% or 95% relative humidity (RH) before storage in air at 12°C and 65% or 80% RH for 144 days. Fresh weight was assessed right after harvest along with carotene (milligram per 100 grams fresh weight), carbohydrates (milligrams per gram dry weight) and internal color (L, a, b). Percent weight loss and all quality components were assessed immediately after curing and every 48 days thereafter. Weight loss increased with days in storage and was substantially minimized by a humidified environment down to 6%. The 95% curing treatment reduced weight loss to levels below the upper threshold for consumer acceptance (<15%) after 144 days. Maturity at harvest did not affect weight loss during storage, but rather the percent dry weight. Beta-carotene increased by >100% during storage. A positive correlation was established between weight loss and beta-carotene and also between the a value and beta-carotene. Curing at 95% RH obviously reduced beta-carotene content to less than one-third of its corresponding amount in noncured fruit. Sucrose increased as glucose and fructose and starch decreased during storage in cured and noncured fruit. Starch was found to decrease by 26% after 144 days in storage. The lowest levels of starch were found early during storage in fruit cured at 95% RH, but the difference between treatments disappeared by the end of storage.
Effect of Foliar Application of Urea and Boric Acid on Red Roomy Grapevines: I. The Effect on Behavior of Buds, Growth, and Vine Nutritional Status
Authors: Akl A.M. , Wassel A.M. , Ahmed F.F. , Hady M.A. Abdel
Published: February 2019

This study was performed during the 1991, 1992, and 1993 seasons to study the effect of different concentrations and number of sprays urea and/or boric acid on behavior of buds, vegetative growth, and vine nutritional status of Red Roomy grape vines. Two, three, four, or five sprays for both urea at 0.5%, 1.0%, or 1.5% and/or boric acid at 0.1%, 0.2%, 0.3% in addition to the control treatments were applied. A gradual increase was observed in the percentages of burst and fruiting buds, main branch length, leaf area, cane thickness, total chlorophyll, and total carbohydrates in the leaves and considerable depression was observed in the percentages of dormant and vegetative buds. The most pronounced effect on growth and nutritional status was detected on vines sprayed four times with urea at 1.0% plus boric acid at 0 2% during the growing season.
Optimization of Parameters for Particle Bombardment of Genes to Garlic
Authors: Myers J. Michele , Simon Philipp W.
Published: February 2019

We evaluated the efficiency of transformation in garlic for promoter activity, osmoticum effect and shaker speed using particle bombardment as the method of gene delivery. Callus was produced from root segments on a modified B-5 medium for four garlic clones. Suspension cultures were then established on a modified B-5 medium + 2,4-D using 6-month-old callus. Cells were collected by vacuum filtration and the Bio-Rad PDS-1000/He system was used to deliver genes. The activities of CaMV 35S, maize Adh1, and rice Act promoters were evaluated for transient expression using the β-glucuronidase (GUS) reporter gene. Osmotic conditioning of cells was performed by adding both mannitol and sorbitol to the medium. Osmoticum effect was evaluated for enhancement of transformation efficiency using GUS. The effect of shaker speed (120, 180 and 240 rpm) on cell type was evaluated for transformation efficiency using GUS. CaMV 35S promoter activity was much higher for garlic than either the maize Adh1 or rice Act promoters. Osmoticum did not enhance promoter activity, but differences in response to osmoticum among garlic clones were observed. Shaker speed did affect cell type, and transformation efficiency was greatly increased at higher shaker speeds. Confirmation of stable transformation and regeneration are in progress.
Factors Affecting Agrobacterium-mediated Transformation of Common Bean (Phaseolus vulgaris L.)
Authors: Zhang Zhanyuan , Mitra A. , Coyne D.P.
Published: February 2019

Factors influencing Agrobacterium–mediated DNA transfer of P. vulgaris were examined using an intron-containing β-glucuronidase (GUS) gene as a reporter system. Tissue culture procedures used were based on direct shoot organogenesis. Two A. tumefaciens strains, A2760 and EHA105, were used with more emphasis on the former due to its overall higher transformation rate. Ten bean entries including breeding lines and cultivars from both Meso-American and Andean origins were compared for compatibility with the two bacterial strains under different pre- and coculture conditions. Pinto `Othello' was extensively used in testing different transformation conditions. Factors found to have significant effects on transformation rate included Agrobacterium-host interactions, explant maturity, preculture and cocultivation conditions, as well as selection schemes, based on transient expression. Some factors, such as the effect of explant maturity and dark preconditioning of explants on gene transfer, have not been reported before. The best transformation conditions included the use of susceptible genotypes and mature explants, preconditioning of explants in darkness, followed by a maximum cocultivation period in the presence of cytokinin, and the use of high selection pressure.
Two-year Evaluation of Pansy Cultivars in the Florida Landscape
Authors: Howe T.K. , Waters W.E.
Published: February 2019

Pansy cultivars were evaluated for number of days to flower, flower size, flower color, plant habit, plant dimensions, weather tolerance, floriferousness, uniformity, and overall appearance during the winters of 1994–95 and 1995–96. In 1994–95, the number of days from sowing of seed to first flower among 122 cultigens ranged from 68 days for `Allegro Beaconsfield' to 94 days for `Springtime New Red'. Flower diameter ranged from 4.1 cm for `Allegro Pure Yellow' to 6.5 cm for `Bingo Yellow with Blotch'. Plant height after 114 to 122 days from seed sowing ranged from 11.4 cm for `Allegro Pure Orange' to 19.7 cm for `Fama See-Me'. Subjective ratings showed few differences among the cultigens in plant uniformity and floriferousness, but differences with respect to overall appearance. In 1995–96, the number of days from seed sowing to first flower for 113 cultigens ranged from 75 days for `Rally Light Blue with Blotch' to 97 days for `Happy Face White'. Flower diameter ranged from 4.8 cm for `Sprite Beaconsfield' and `Sprite Yellow' to 7.5 cm for `Bingo Yellow with Blotch'. Plant height at 140 to 143 days after seed sowing ranged from 12.4 cm for `Maxim Chiffon' to 26.5 cm for `Universal Plus White'. Subjective ratings showed no differences among the cultigens in plant uniformity or overall appearance and few differences in floriferousness or flower display.
Advanced Evaluation System of Hazelnut Germplasm
Authors: Wang Mingqi , Peng Lixin , Wu Banghua
Published: February 2019

Based on our investigation of hazelnut germplasm and Thompson's evaluation system for European hazelnuts, an in-depth study on character description of hazelnut germplasm was conducted from 1991 to 1994. Eighty characters were evaluated for the 58 tested species. It was found that eight characters should be eliminated from Thompson's system, such as annual branch length and hair, lentical color, and serration depth. The best leaf sampling position, sample volumes for quantitative characters, and scoring standards were also determined. Therefore, an advanced evaluation system for hazelnut germplasm was developed. The advanced system is easier and simpler, and will significantly expedite systematical studies of hazelnut germplasm.
Cultivar and Conditioning Treatment Affect Development of Red Drupe in Blackberry Fruit
Authors: Perkins-Veazie P. , Collins J.K. , Clark J.R.
Published: February 2019

Blackberry fruit often exhibit an unattractive discoloration following harvest and storage. This redness appears at random on the berry and has been associated with sunburn or high temperature damage, or with fruit harvested less than fully ripe. We began a study to separate and identify causes of red drupe. Black (fully ripe) berries, free of sunburn, of six blackberry cultivars were harvested in the morning and subjected to conditioning treatments of 20 hours at 2 or at 20°C, followed by 7 days storage at 2°C. Strong cultivar differences and effects of conditioning treatment were found. `Navaho', `Arapaho' and `Chester' had little or no red drupe, regardless of conditioning treatment. As much as 50% of `Shawnee' and `Choctaw' berries exhibited red drupe, with more appearing in fruit conditioned at 2°C. Development of red drupe in berries conditioned at 2°C was quadratically related to total anthocyanin and juice pH, while that of fruit conditioned at 20°C was quadratically related to percent titratable acidity. The red drupe disorder in blackberries is exacerbated by low temperature storage and may be due to decreased cellular pH and subsequent anthocyanin glycosylation in individual drupelets.
Optimizing Bud Harvest Time and Duration of Temporary Cold Storage for Cryopreservation of Dormant Apple Buds
Authors: Forsline Philip L. , McFerson James R. , Lamboy Warren F.
Published: February 2019

The USDA–ARS active collection of Malus includes over 2500 accessions maintained as field-grown trees at the Plant Genetic Resources Unit (PGRU), Geneva, N.Y. Nearly 30% of this collection is presently cryopreserved as dormant buds at the National Seed Storage Laboratory, Fort Collins, Colo., as a backup security collection. Successful bud-grafting recovery rates (≥40%) after one to four years of cryogenic storage have been documented for over 675 of 750 accessions tested. However, current protocols dictate budwood collection at PGRU from late December through early March, when buds are thought to be optimally acclimated for desiccation and slow freezing to –30°C, our pretreatment for cryopreservation. This causes a processing bottleneck. Our observations suggest temporary storage of budwood at –4°C after field harvest is possible, but we had not tested this directly. Therefore, we collected budwood from four accessions representing different levels of cold tolerance on six dates from January to March, 1995. Dormant buds were processed for cryopreservation monthly after storage in sealed bags at –4°C for 1 to 6 months. Recovery rates ranged from 55% to 100%. Neither collection date nor length of storage at –4°C affected rate of recovery. These results suggest we can significantly increase the throughput and efficiency of our cryopreservation efforts, thereby enhancing management and security of the Malus collection.
Comparing Potting Media Available to Consumers through Garden Centers and National Chain Stores
Authors: Kuhns Larry J. , Harpster Tracey L.
Published: February 2019

A study was initiated to determine how well plants would grow in potting media available to consumers through garden centers and national chain stores. Nine media were evaluated. The chemical and physical characteristics were determined, and six geraniums (Pelargonium sp) and six marigolds (Tagetes patula) were grown in each of the media. Three of each six were fertilized, three were not. The plants that were fertilized received 100 ppm N and K and 50 ppm P once a week. Three months after seeding the flowers, flowers and buds on the marigolds were counted and the plants were harvested. Dry weights were determined. Nitrate-N ranged from 6 to 627 ppm, pH from 4.9 to 7.1, phosphorus from 88 to 502 pounds/A, potassium from 1.0 to 6.9 meq/100 g, magnesium from 1.4 to 10.8 meq/100 g, calcium from 5.2 to 30.0 meq/100 g, soluble salts from 20 to 151 mmhos, and CEC from 13.0 to 43.8 meq/100cc. Bulk density ranged from 21 to 53 g/100cc, water holding capacity from 32 to 53 ml/100cc, percent air-pore space from 2.7 to 15.7, and total porosity ranged from 65% to 78%. Unfertilized marigolds weighed between 0.1 and 9.6 g; fertilized marigolds weighed 1.4 to 17.2 g. Unfertilized geraniums weighed between 1.4 and 23.3 g; fertilized geraniums weighed 4.4 to 56 g. There were 1.3 to 16 flowers on unfertilized and 7 to 24.3 flowers on fertilized marigolds.
Number of Containers Affects Nitrate Nitrogen in Runoff
Authors: Cashion Geraldine J. , Yeager Thomas H.
Published: February 2019

Multiple branched liners of Rhododendron sp. cv. Duc de Rohan were potted in 3-L containers using a 5 pine bark: 5 Florida peat: 1 sand medium (by volume) amended with Prokote Plus (20N–1.3P–8.3K, 9.2 kg·m–3) and placed on one of five treatment platforms (1.2 × 2.4 m) in a commercial nursery in Manatee County, Fla. Treatments were 88 plants per square grid with containers touching (T1), 44 plants per square grid with containers touching (T2), 44 plants per square grid with containers touching in rows and 15 cm between rows (T3), 22 plants per square grid with containers touching (T4), and 22 plants per square grid with 15 cm between containers in rows and 15 cm between rows (T5). Irrigation was applied by overhead impact nozzles (0.13 cm/0.5 h) before collecting runoff. Runoff volume was measured and ppm nitrate N determined on day 6, 23, 38, 63, 92, 161, 189, 217, and 274. Average nitrate N ranged from 97 ppm for T1 to 10 ppm for T5 and corresponded to volumes of 19 and 20 L, respectively. Volumes were not different due to spacing or number of containers; however, nitrate N increased linearly with container number when containers were touching (T1, T2, and T4). Nitrate N in runoff was similar for the same number of containers regardless of spacing.
Changes in Soluble Carbohydrates in Floral Organs of Lilium longiflorum during Flower Development
Authors: Ranwala Anil P. , Miller William B.
Published: February 2019

Easter lily flower buds at five stages of development (stage 1, 3–4 cm in length; stage 2, 6–7 cm; stage 3, 9–10 cm; stage 4, unopened buds, 13–14 cm; and stage 5, open flower one day after anthesis) were harvested, and flower organs were dissected for carbohydrate analysis. Extracting soluble sugars in distilled water at 70°C gave the optimum yield of soluble sugars among the several extraction methods tested including 80% ethanol, and distilled water at various temperatures. Separation of the extracted soluble sugars by alkaline high performance anion exchange chromatography revealed the presence of glucose, fructose, sucrose, and two other sugars of unknown identity. Glucose and fructose concentrations increased remarkably during the flower development in sepal (about 15-fold), style (about 10-fold), and filament (about 5-fold), while sucrose levels remained constant at low concentrations. In stigma, sucrose levels increased parallel to the increase of hexose sugars during development. Ovary had high sucrose levels relative to hexoses that remained constant while hexoses increased gradually. In anther, hexose concentrations increased at the stage 2 and then dropped at stage 3 and 4. Sucrose levels were higher than hexoses in anther, and it increased from stage 1 to stage 2, then dropped at stage 3, and increased thereafter. In addition to these sugars, anthers at stages 2 and 3 had a series of late eluting oligosaccharides. These oligosaccharides could be hydrolyzed to glucose with hot 1 m H2SO4 or with amyloglucosidase.
Response of New Guinea Impatiens to Various Water Qualities in a Subirrigation System
Authors: Armstrong Traci , Kent Matthew W. , Reed David Wm.
Published: February 2019

With the rising concern for the environment and an increase in governmental regulation, greenhouse growers must find alternative methods for irrigation that will avoid ground and surface water contamination. Subirrigation is one of these alternatives, but subirrigation is more sensitive to water quality than traditional systems and many growers are faced with poor water quality. This experiment tested seven different water sources from across the state of Texas. Each source was replicated twice using New Guinea impatiens `Illusion'. Leaf count, plant height, and plant width were measured at 2-week intervals. Plants were harvested at 8 weeks and measured for shoot fresh weight, shoot dry weight, and overall quality. Electrical conductivity of the upper, middle, and bottom layers of the container medium was measured. Compared to the reverse osmosis control, fresh weight was reduced by 12% to 30%, average leaf number by –7% to 56%, quality evaluation by –8% to 61%, average width by –5% to 27%, and the average height by 8% to 34%. The results will be explained based on differences in analysis of the various water and media samples.
INFLUENCE OF LIGNITE-ACTIVATED WATER ON SEED GERMINATION, CUTTING PROPAGATION, AND PLANT PERFORMANCE
Authors: Emrick Rachel , Creech D. L. , Bickerstaff G.
Published: February 2019

This project tested rates of lignite-activated water (LAW) for its influence on seed germination, cutting propagation, and plant performance. LAW is a product of CAW Industries, Rapid City, S.D. LAW is water-activated by lignite in a process that includes the addition of sulfated castor oil, calcium chloride, magnesium sulfate, sodium meta silicate, and fossilized organics from refined lignite. LAW is reported to improve many plant performance traits. Four rates were used in this study. Seed germination trials indicated no significant differences in germination percentage with LAW applications with the two species tested, Echinacea purpurea and Hibiscus dasycalyx. In a “closed” system, LAW enhanced cutting propagation success of Aster caroliniana, Cuphea micropetala, and Verbena `Homestead Purple', as measured by percent rooting and dry weight of roots produced. Cutting propagation of two woody species, Illicium henryi and Rosa banksiae, was not improved with LAW additions. In the SFASU Arboretum, pansy performance, as measured by plant dry weight, was improved one month after establishment.
OZONE SENSITIVITY OF BUDDLEIA CULTIVARS
Authors: Findley Doug , Keever Gary J. , Chappelka Arthur H. , Gilliam Charles H. , Eakes D. Joseph
Published: February 2019

Five cultivars of buddleia, Buddleia davidii, were exposed to subambient, ambient, and twice-ambient levels of ozone in open-top chambers for 8 weeks during 1995. Plants were evaluated for foliar injury, growth index, and inflorescence characteristics during and following the exposure period. Destructive harvests were conducted at the end of the exposure period to determine the dry weight of both above- and below-ground plant components. All cultivars showed signs of visible injury in the twice-ambient treatment at both 3 and 8 weeks after treatment initiation (WAT). At 3 WAT, `Pink Delight' was the most severely injured, followed by `Opera'. The other three cultivars had similar lower levels of foliar injury. Reductions in growth index as well as dry weight were found for all cultivars in the twice-ambient treatment. The number of developing floral buds and inflorescences was reduced in the twice-ambient treatment for all cultivars. Differences among the cultivars was due to normal differences in growth habit and not due to elevated ozone levels. These data indicate that Buddleia cultivars are sensitive to levels of ozone similar to those found in urban areas of the southeastern United States.
EVALUATION OF SUMMER COVER CROPS FOR USE IN VEGETABLE PRODUCTION SYSTEMS
Authors: Creamer Nancy G.
Published: February 2019

Five grasses, six broadleaf species, and five legume/grass mixtures were evaluated for their production of aboveground biomass (AGB), nitrogen contribution, C: N ratio, ability to compete with weeds, and susceptibility to three methods of mechanical kill. Of the legume species, sesbania, cowpea, and soybean produced the most biomass, which totaled 5542, 4227, and 3934 kg·ha–1, respectively. Nitrogen in the AGB of these species was 109, 95, and 83 kg·ha–1, respectively. AGB production of the grass species ranged from 8677 kg·ha–1 for sorghum–sudangrass to 5247 kg·ha–1 for pearl millet. Nitrogen in the AGB for the grass species ranged from 68 to 38 kg·ha–1. In general, the cover crops most competitive with weeds were those that had an excess of 3900 kg AGB/ha. The broadleaf species were effectively controlled by mowing, while undercutting controlled five of the species, and rolling provided little control. Undercutting provided the best control of the grasses, while rolling was effective on the most mature species, and mowing provided little control.
GROWTH REGULATORS: FRUIT SET EXPERIMENTS ON BLUEBERRIES IN SOUTHERN GEORGIA
Authors: Mullinix Benjamin , Krewer Gerard , Nesmith Scott , Scarborough S. , Clark J. , Stanaland D.
Published: February 2019

Five experiments were run using surfactants and gibberellic acid (ProGibb). Fruit set is a problem with rabbiteye blueberry plants. Gibberellic acid sprayed on plants when they are in bloom does enhance fruit set. Currently, it costs $247/ha to achieve this enhanced fruit set. `Tifblue', `Climax', and `Woodard' cultivars were used in on-farm experiments. Usually, applications of 80 + 80 are used. With use of X-77 and L-77 surfactants, rates were reduced to 40 + 40. Other rates examined were 32 + 32, 24 + 24, 16 + 16 + 16. Fruit was enhanced significantly over no spraying. Airblast I sprayer performed better PropTec, whether used for day or night applications. Spraying slanting downward produced greater fruit set than from the side. E1: Trt = 15 – 20, C = 11 lb/lo. E2: 32 + 32 = 12, 16 + 16 = 7 lb/lo. E3: AB = 64, PT = 48 %FS; Trt = 56, C = 35 %FS; `C' = 73, `T' = 39 %FS. E4: 5% FS with Trt; `T' = 53, `W' = 57 %FS. E5: 30 + 30 = 87, – 40 + 40 = 80 %FS.
FERTILIZING MATTED ROW STRAWBERRIES: AN OVERVIEW
Authors: Himelrick David G. , Woods Floyd M.
Published: February 2019

Generalized recommendations for the southeastern U.S. would typically include soil testing well in advance of establishment. Lime, P, and K should be applied at least 2 weeks before planting. Nitrogen is either broadcast and incorporated before planting or sidedressed 2 to 4 weeks after planting at 30 to 70 kg·ha–1. Additional N at 30 to 65 kg·ha–1 is applied late August to mid-September. A late winter N application at 20 to 30 kg·ha–1 is suggested for sandy soils. On established plantings fertilization takes place at renovation, with P and K being applied based on soil test or foliar analysis results. Nitrogen rates are typically in the range of 35 to 60 kg·ha–1. Later season fertilization generally follows the rates and timings of fall and winter recommendations of the establishment year. Minor nutrients can be limiting on sandy soils and B may be required in a wider range of soil types.
CONTAINER PRODUCTION OF UNDERUTILIZED URBAN TREES USING KENAF AND COCONUT COIR PITH
Authors: Goyne Mitchell W. , Arnold Michael A.
Published: February 2019

Growth responses during nursery production in 2.2- and 11.4-liter plastic containers to conventional and alternative media of four species of small trees of limited availability for potential use in urban sites in the southwest United States (Acacia wrightii, Chilopsis linearis, × Chitalpa tashkentensis, and Rhus lanceolata) were compared to that of a commercially available small tree (Fraxinus velutina). Four media combinations, at 3:1 (v/v) of bark: sand (conventional), bark: coconut coir pith, kenaf stalk core: peatmoss, and kenaf: coir, with three fertilizer concentrations (3.6, 7.2, and 10.7 kg·m–3 of 18N–2.6P–10K Osmocote) were tested with each species. All species exhibited commercially acceptable growth (80 to 167 cm mean heights in 11.4-liter containers in 240 days) with near 100% survival in most media and fertilizer combinations with the following exceptions: shoot extension of Rhus lanceolata was reduced by 20 to 30 cm and survival by 20% to 50% in kenaf media with high fertility rates; and Acacia wrightii had acceptable shoot extension but exhibited poor trunk diameter growth across media relative to the other species. Slightreductions in growth of some species were noted with kenaf media and slight increases with coconut coir, but differences were not likely of commercial significance. Kenaf media was significantly lighter (20% to 80%) than bark media, but had elevated initial electrical conductivity (EC) and shrank to 60% to 70% of its initial volume after 240 days. Kenaf: peatmoss media had a slightly lower mean pH (6.34) compared to the other media (pH 6.41–6.49).
MECHANICAL AND CHEMICAL ALTERNATIVES FOR WEED CONTROL IN WATERMELON
Authors: Roberts Warren , Shrefler Jim , Duthie Jim , Edelson Jonathan
Published: February 2019

A study was conducted in southeastern Oklahoma to determine treatments or combinations of treatments that provided the best weed control and crop yield for watermelon. `Allsweet' watermelons were grown with different combinations of mechanical and chemical weed control. Treatments included naptalam, clomazone, naptalam + clomazone, bensulide, naptalam + bensulide, napropamide, trifluralin, dcpa, ethalfluralin, sethoxydim, paraquat, glyphosate, cultivation, cultivation + hoeing, cultivation + paraquat, cultivation + glyphosate, and one treatment with no weed control. Glyphosate and paraquat were applied as wipe-on when weeds were taller than watermelons. The five treatments with greatest yields were (in descending order) cultivation + hoeing, trifluralin, cultivation + paraquat, cultivation, and dcpa. The treatments with lowest yield were the control, paraquat, glyphosate, and naptalam. A visual rating (0–10, 0 is poor, 10 is ideal) was taken about 5 weeks after seeding. Treatments with a visual rating of 6 or more were trifluralin (9.4), cultivation + hoeing (9.3), napropamide (9.3), cultivation + glyphosate (7.5), cultivation + paraquat (6.8), dcpa (6.7), and cultivation (6.5). With the exception of the cultivation + hoeing, all plots were weedy at harvest time. Suppression of selected weeds by a herbicide usually allowed rapid growth of the remaining weeds.