bluuebunny/crossref_metadata_2025_split huggingface dataset:
VA MYCORRHIZAL INFLUENCE ON GROWTH AND MINERAL UPTAKE OF POTATO
Authors: McArthur D.A.J. , Knowles N.R. 
Published: February 2019

The growth response of potato to infection by vesicular-arbuscular mycorrhizal fungi (VAM) (Glomus dimorphicum, G. intraradices, and G. mosseae), at increasing levels of soil phosphorus (P), was related to VAM-altered mineral status of the plant. In addition, the morphological development of the VAM was characterized using light and scanning electron microscopy.Four weeks after inoculation, arbuscules and coiled hyphae were the predominate fungal structures within the roots, however, vesicle development increased steadily over the remainder of the 12 week growth period. As expected, the percent infection of roots by VAM decreased with increasing soil-P level. Leaf area, relative growth rate (RGR), lateral branching and root dry weight were increased by VAM, although the relative-response diminished with increasing soil-P level. A similar response to VAM-infection was evident for the concentration of and total shoot N, P and K. Examination of the shoot N status indicated that VAM influenced the rates at which the plant was partitioning N into various N pools. But again, differences between non-VAM and VAM plants tended to decrease with increasing soil-P level. These results indicate that VAM modification of dry matter accumulation and nutrient uptake is mostly a consequence of the alleviation of P-deficiency of the plant and the improved growth of roots, allowing increased mineral absorption.
EFFECT OF TWO-SPOTTED SPIDER MITE FEEDING ON GAS EXCHANGE AND CHLOROPHYLL CHARACTERISTICS OF RED RASPBERRY LEAVES
Authors: Cameron J. Scott , Hartley Carol A. , Shanks Carl H. , Garth Jeannie K. L. 
Published: February 2019

At two-week intervals from 17 June to 15 July, three groups of `Meeker' red raspberry plants were infested with two-spotted spider mites (Tetranychus urticae) in a greenhouse. While populations on individual plants were allowed to develop freely, control plants were kept free of mites with a chemical miticide. Gas exchange measurements were made on 27 July prior to visible mite damage, and on 7 October after injury was apparent. The relationships between mite populations and leaf gas exchange and chlorophyll characteristics were described using a logarithmic function.Physiological responses to mite feeding were observed prior to visible leaf injury. On both dates, CO2 assimilation rates decreased (p ≤ 0.001) with increasing mite numbers per leaflet. On 27 June, a significant relationship (R2 = 0.61***) was found between mite number and mesophyll conductance (gm). On 7 October, significant relationships (p ≤ 0.001) were also observed with gm, stomatal conductance (gs), and transpiration (E). Total chlorophyll content of leaves decreased with increasing mite populations, but chlorophyll a/b ratio and dry weight per leaf unit area were unchanged.
PRODUCTION OF SOME FLOWERS IN HYDROPONICS AND SOILLESS MEDIA
Authors: Al-Mana Fahed A. , El-Kiey Tarik M. 
Published: February 2019

Production of five commercial cut flowers in different culture media, namelyI nutrient film technique (NFT), soilless media (perlite and an equal mix of perlite and peatmoss), and soil mix (2 sand: 1 loam by volume), was investigated in controlled fiberglass-house. Two rose varieties (Rosa hybrida var. Baccara and Madina); carnation (Dianthus caryophyllus var. William Sim); Chrysanthemum morifolium var. Delta, and Dahlia hybrida var. variabilis were used. Plants were watered as they needed by the same nutrient solution used for NFT.Generally, growth and yield of Baccara and Madina roses, Chrysanthemum and Dhalia plants were superior in NFT than in the other media. On the contrary, the growth and yield of carnation plants were significantly greater in conventional soil or perlite and peatmoss mix than in NFT or perlite.Flower crops grown in NFT generally reached harvest stage 5-10 days earlier than those grown in the other media except carnation plants. There were variations in the accumulation of N, P, K mg, ca, and Fe in plant leaves among the various culture media.
HORTICULTURAL THERAPY
Authors: Flagler Joel 
Published: February 2019

It has been observed that the process of horticulture can help to heal physical, mental, and social disabilities. Professionally trained horticultural therapists prescribe and administer planting and gardening activities to provide benefits to people of all ages and abilities. Horticultural therapy programs are now commonplace in hospitals, geriatric centers, schools, rehabilitation facilities, community gardens and prisons. One common goal in all of these programs is to help heal, teach and retrain individuals through the use of plants.As a result of repeated successes, horticulture is being widely accepted as an effective therapeutic tool. Research is underway to measure the effectiveness of horticultural therapy in clinical and correctional settings. Databases are being developed to document and substantiate the beneficial effects of horticulture on human well-being. With such research results we can better understand the value of horticultural therapy in the recovery and rehabilitation processes.
SWEET CORN YIELD AND INSECT DAMAGE AS AFFECTED BY COVER CROPS AND NITROGEN
Authors: Roberts Warren , Cartwright Bob 
Published: February 2019

The effects of cover crops and nitrogen on yield and insect damage of sweet corn were examined. In 1989, sweet corn was grown in bare soil plots, plots covered with rye (Secale cereale), and plots covered with hairy vetch (Vicia villosa). In 1990 a black plastic mulch treatment was substituted for the hairy vetch treatment. Each soil cover was fertilized with 45, 90, 134, or 179 kg/ha nitrogen (N) in 1989, and 34, 101, 168, 235, or 302 kg/ha N in 1990. Covers were planted in the fall, followed by sweet corn the following spring. There was no mowing or tilling of the cover crops.
Corn yields were lower each year in the rye covered plots. There were more corn earworms on the rye covered plots. Corn pollination was poorer on the rye covered plots, but responded positively to increasing rates of N.
EFFECTS OF SURFACE MOISTURE AND COLONIZATION BY INA BACTERIA ON FROST DAMAGE TO TOMATO SEEDLINGS
Authors: Drown Glenn , Anderson Jeffrey 
Published: February 2019

Natural colonization of tomato transplants (Lycopersicon esculentum Mill. `Supersonic') by ice nucleation active (INA) bacteria was monitored during a warm, dry period in the spring and during a rainy period in the fall. Populations of INA bacteria and freezing temperatures were determined for seedlings on days 1 to 5, 7, 9, 12, and 15 after transplanting. During the spring experiment, plant freezing temperatures ranged from -6.4C to -3.6C. INA bacteria were detected from day 1 after transplant with populations ranging from 6 to 630 cells/g fresh wt. Most plants had detectable levels of INA bacteria after 3 days in the field, but some plants did not have detectable levels after 15 days. In the fall, populations of INA bacteria were similar to spring levels for the first week after transplant. Numbers of INA bacteria were higher and plant freezing temperatures warmer on days 9 through 15 in the fall compared with the same period in the spring.
Laboratory experiments were conducted using plants without INA bacteria. Seedlings with dry surfaces supercooled to lower temperatures than tomato plants with wet surfaces.
CONTRIBUTION OF CARBON AND NITROGEN RESERVES TO VEGETATIVE AND REPRODUCTIVE GROWTH OF RABBITEYE BLUEBERRY
Authors: Birkhold Keith T. , Darnell Rebecca L. 
Published: February 2019

Partitioning of carbon and nitrogen reserves were examined in two cultivars of rabbiteye blueberries (Vaccinium ashei] differing in their timing of vegetative budbreak relative to floral budbreak. Floral budbreak precedes vegetative budbreak in `Climax', while floral and vegetative budbreak occur concomitantly in `Bonita'. Twenty eight containerized plants from each cultivar were dual labeled in the fall with 105 μCi of 14C02 and 0.6 g of nitrogen enriched with 5% 15N. Plants were grown outdoors throughout the winter and the following growing season. At five dates, beginning 27 days prior to full bloom and ending at fruit maturity, plants were harvested into old shoots, roots, fruit, and vegetative growth. Fall leaf drop accounted for loss of 12% of applied N and 20% of applied 14C. In the first harvest, approximately 73% of the recovered 15N and 50% of the recovered 14C was in the roots for both cultivars. By fruit maturity, approximately 8% of the recovered 15N was in the fruits, 51% in new vegetative growth, and 41% in old shoots and roots. Approximately 1.2% of the recovered 14C was in fruit, 1.5% in vegetative growth, and 97% in old shoots and roots. Data suggest that differences in the timing of vegetative budbreak between these two cultivars do not influence overall partitioning patterns of reserve carbon and nitrogen.
MECHANICAL BUD DAMAGE TO BRANCHED AND UNBRANCHED `BRADFORD' PEAR TREES DURING POST HARVEST HANDLING
Authors: Jacyna Tadeusz 
Published: February 2019

Branched (B) and unbranched (UB) one-year-old `Bradford'/`OHFx97' trees were examined at intervals between preparation for bare root harvest and long term storage to determine the extent of mechanical bud damage caused by the various handling steps. After hand stripping of leaves, digging, transportation to the storage facility, and grading, and tying of bundles, there was a marked difference in the percentage of damaged buds between branched (26%) and unbranched (53%) trees. The B/UB live bud ratio before and after harvest was 1:0.45 and 1:0.26, respectively. This difference may have been due to a various morphological growth pattern which both types of trees had produced.
EFFECTS OF MYCORRHIZAE, MEDIA AND CONTAINER TYPE ON THE GROWTH OF GREEN PEPPER AND LETTUCE TRANSPLANTS
Authors: Watson Ray A. , Stewart Katrine A. , Furlan Valentin 
Published: February 2019

The effects of two mycorrhizal species (Glomus versiforme and Glomus intraradix) and a control on the growth of green pepper, Capsicum annuum, and lettuce, Lactuca sativa, seedlings have been evaluated using four types of growing media (Peatwool, Fafard bulk mix. Cornell mix and a compost based mix) and two types of containers, Cell Packs (125 cc volume) and Pro-Trays (65 cc volume) for green pepper and Cell Packs (125 cc volume) and Plug Flats (33 cc volume) for lettuce. The experiments were split plot randomized Complete block design with 6 blocks (lettuce) and 4 blocks (pepper). Seeds were sown directly into the containers of mycorrhizal inoculated media. All treatments received the same fertilizer regime. Cell volume had no significant effects on green pepper fresh weight, dry weight, stem diameter, leaf area or leaf number but the lettuce Cell Pack plants had significantly higher fresh and dry weights, more leaves and higher leaf area. The Fafard Bulk and the Compost mix gave significantly higher fresh and dry weights than did the other two media for both green pepper and lettuce. Mycorrhizal species did not influence plant growth with the exception of leaf area in green peppers and shoot dry weight in lettuce.
EFFECTS OF COMPACTION ON SUBSTRATE CO2 IN A SUBIRRIGATION SYSTEM
Authors: Khoury Noreen S. , Holcomb E. Jay 
Published: February 2019

Greenhouse substrates are designed to allow maximum aeration. Substrate water holding capacity can be increased by media compaction. Six inch standard pots, fitted with gas tight openings for removing gas samples, were filled with Metromix 350 and Peatwool at 2 different compaction rates. Half the pots were planted with rooted cuttings of Poinsettia pulcherrima `Glory' and half were left fallow. Air samples were taken at both wet and dry soil moisture conditions at early, mid point and at the end of the cropping cycle. In general, wet substrates had higher CO2 than drier substrates and more compacted substrates had higher CO2 than less compacted. CO2 decreased with time in all treatments. The highest CO2 levels occurred in wet heavily compacted Peatwool with a plant and the lowest occurred in dry Metromix with no plant.
IN VITRO ORGANOGENESIS OF `BEAUREGARD' SWEETPOTATO
Authors: Rivas Roberto A. , Evans P.T. , LaBonte D.R. 
Published: February 2019

Methodology is presented for organogenesis of `Beauregard sweetpotato, a cultivar released in 1987 that is rapidly increasing in commercial use in the U.S. Regeneration of `Beauregard' sweetpotato plantlets was obtained when complete leaves and 10 mm internode explants were cultured in liquid and solid media respectively over a period of 8 weeks. Leaves in liquid Murashige and Skoog medium containing 2 mg/l of IAA placed on a shaker under dark conditions produced white callus at the cut end of the petiole and roots underneath the callus in 4 weeks. Leaves were subsequently transferred to MS medium containing 500 mg/l of Chlorocholine chloride (CCC) and 0, 1, 5 and 10 mg/l of BAP for 4 more weeks. Shoots were regenerated from callus using 1 mg/l of BAP. The effect of NAA auxin and various concentrations of the cytokinin Thidiazuron on internodes was examined under 16 hr. light and 8 hr dark photoperiod using MS solid medium. Explants on 0.05 mg/l NAA alone produced roots and shoots. The most plantlets however, were regenerated using 0.05 mg/l of NAA and 0.01 mg/l Thidiazuron. Regeneration of plants from leaves and internodes may be a useful system for a clean and rapid propagation of `Beauregard' sweetpotato.
INFLUENCE OF SUPRAOPTIMAL ROOT-ZON E TEMPERATURES ON RUBISCO ACTIVITY, CHLOROPHYLL AND CAROTENOID LEVELS IN `ROTUNDIFOLIA' HOLLY
Authors: Ruter John M. , Ingram Dewayne L. 
Published: February 2019

High root-zone temperatures have been shown to affect photosynthate partitioning, respiration, nitrogen nutrition and growth of `Rotundifolia' holly. The loss of chlorophyll and protein in shoots of other plants in response to high root-zone temperatures has been documented. Therefore, the objectives of this research were to look at the effects of supraoptimal root-zone temperatures on RUBISCO activity, leaf protein and photosynthetic pigment levels. Soluble protein levels in leaves increased linearly as root-zone temperature increased from 30 to 42 C. RUBISCO activity per unit protein and per unit chlorophyll responded quadratically to root-zone temperatures. Total chlorophyll, chlorophyll a & b, and carotenoid levels decreased linearly with increasing root-zone temperature. It is possible that `Rotundifolia' holly was capable of redistributing nitrogen to maintain RUBISCO activity for photosynthesis.
MINIMUM IRRIGATION OF LANDSCAPE GROUNDCOVERS.
Authors: Pittenger D.R. , Hodel Donald R. , Shaw David A. , Holt D.B. 
Published: February 2019

A previous field study had shown that Baccharis pilularis, `Twin Peaks', Drosanthemum hispidum, Vinca major, Gazania hybrid, Potentilla tabernaemontanii and Hedera helix, `Needlepoint', express no loss in relative aesthetic appearance when irrigated for one season at 50% of reference evapotranspiration (ETo), but three species did not perform acceptably at 25% of ETo. In this study these six species were grown in the field for 16 months under treatments of 50%, 40%, 30% and 20% of real-time ETo to more closely determine their minimum irrigation needs.
Analysis of seasonal plant performance ratings indicates that for Vinca, Gazania and Potentilla there is no significant increase in relative performance when irrigated at more than 30% of ETo. Baccharis, Drosanthemum and Hedera exhibited no significant improvement in performance when irrigated above 20% of ETo. A general decline in aesthetic appearance and performance was observed during the study in Gazania and Potentilla at all treatments, suggesting that their long-term minimum irrigation need may be more than 50% of ETo.
NITROGEN LEACHING LOSSES FROM CONTAINER-GROWN ROSES.
Authors: Cabrera Raul I. , Evans Richard Y. , Paul J. L. 
Published: February 2019

Nitrogen leaching losses of 21, 40 and 49% were measured from container-grown `Royalty' roses irrigated for one year with nutrient solutions containing 77, 154 and 231 mg N/l. There were no significant differences in number of flowers per plant or dry matter per plant. The N present in the harvested flowers accounted for 43, 27 and 17% of the N applied for the 77, 154 and 231 mg N/l treatments, respectively.
Plants receiving 154 mg N/l at leaching fractions of 0.1, 0.25 and 0.5 had corresponding N leaching losses of 22, 38 and 56%. In this experiment, however, the 0.5 leaching fraction produced yields significantly higher than those of the 0.1 and 0.25 treatments. The N recovered in the harvested flowers accounted for 28, 25 and 19% of that applied to the 0.1, 0.25 and 0.5 treatments, respectively.
The results of these studies suggest that modifications in current irrigation and fertilization practices of greenhouse roses would result in a considerable reduction of N leaching losses and enhance N fertilizer use efficiency, without loss of cut flower yield and quality.
BLOOM THINNING OF FUJI, ROYAL GALA, AND BRAEBURN APPLE WITH MONOCARBAMIDE DIHYDROGENSULFATE
Authors: Myers Stephen C. , McArtney Steven , Tustin Stuart , Cashmore Wendy , Mangin Richard 
Published: February 2019

Foliar applications of monocarbamide dihydrogensulfate (D-88, Unocal Chemicals Division) at rates of 0, 2.5 ml/1, 3.75 ml/1 or 5.0 ml/1 were made to mature apple trees of “Fuji”, “Royal Gala” or “Braeburn” on MM106 root-stock. Treatments were applied dilute when spurs were at 95% full bloom. D-88 was applied at 5.0 ml/1 to “Fuji” at three different times during the day (0730, 1400 or 1810) with and without surfactant in an attempt to evaluate the effect of different atmospheric and drying conditions. Fruit set (number of fruit per 100 flower clusters) was determined after natural fruit drop.
D-88 had no effect on fruit set of “Royal Gala” or “Braeburn”. There was a linear effect between D-88 rate and fruit set on “Fuji”, with the 5.0 ml/1 rate reducing set by 30%. D-88 affected the number of fruit at individual fruiting sites, most significantly the percentage of flower clusters setting 3 fruits decreasing with increasing rate. Timing and surfactant had no effect.
Fruit finish, mean fruit weight, seed number and soluble solids concentration were measured at harvest.
FOUR NON-CIRCULATING, HYDROPONIC METHODS FOR GROWING GREENHOUSE TOMATOES
Authors: Kratky B.A. 
Published: February 2019

Total salable yields of `Vendor' greenhouse tomatoes produced with 4 non-circulating, hydroponic methods were not significantly different from yields produced with conventional soil bed culture (5.69 kg/plant).
Three methods employed a capillary, sub-irrigated system wherein the plant container rested in a shallow, covered, polyethylene-lined tank containing 5 cm of nutrient solution. Plant containers consisted of 7 and 25 liter plastic pots containing a 1 hapuu:2 cinder medium plus 1 and 2 plants, respectively, and rockwool blocks (7.5 × 7.5 × 6.5 cm) resting on larger rockwool blocks (15 × 15 × 7.5 cm).
The fourth method consisted of rockwool blocks (7.5 × 7.5 × 6.5 cm) resting on a screen placed in a covered, 20 cm deep, polyethylene-lined tank filled with nutrient solution.
VARIABILITY IN CHLOROPHYLL, RUBISCO, AND FOURTH DERIVATIVE SPECTRA AND THEIR RELATIONSHIP TO CO2 ASSIMILATION RATES OF EIGHT FRAGARIA CHILOENSIS GENOTYPES
Authors: Foote Paul W. , Cameron J. Scott , Chen Chuhe , Klauer Stephen F. 
Published: February 2019

Gas exchange rates were measured in the field on middle leaflets of Fragaria chiloensis (L.) trifoliates which were then used for Rubisco quantity and activity assays. Side leaflets of the same leaf were utilized for fourth-derivative spectroscopy, chlorophyll extraction, and specific leaf weight data. Differences of CO2 assimilation (A) rates were highly significant between genotypes ranging from 16.2 to 27.6 μmol CO2·s·m. Chlorophyll a and b, and total chlorophyll per unit area were positively correlated to A (r = 0.48**, 0.45**, and 0.49**, respectively). Total chlorophyll per unit dry weight had a correlation coefficient with A of 0.6**.
Fourth-derivative analysis of in vivo leaf attenuance spectra showed a positive correlation between A and Ca693 peak amplitude and a negative correlation of A and Ca677 peak amplitude. Peak amplitude of Ca693 was also correlated with chlorophyll content.
Activity per unit Rubisco was not a significant factor influencing A, but Rubisco quantity on either a leaf area or a dry weight basis was positively linked to A (r = 0.40** and 0.44**, respectively).
IMPORTING PLANT GERMPLASM INTO THE UNITED STATES
Authors: Dale Mary E. 
Published: February 2019

International plant germplasm resources are an invaluable source of information, and bringing viable plant materials into the United States is a necessity for many researchers.
Quarantine regulations vary based on the plant pests and pathogens occurring in the country of origin to prevent the introduction of injurious plant pests and diseases. These regulations also depend on the type of germplasm (such as live plant, cuttings, or seeds), size and age of specimen, and the media grown in. Plants in soil are prohibited, while those in agar, or bare root may be allowed to enter.
Procedures to follow for bringing plant germplasm of international origin (including CITES species), forms and permits, ports of entry, delays to expect or avoid along with other information on successfully bringing plant germplasm resources into the United States will be discussed.
FERTIGATION EFFECTS ON APPLE TREE GROWTH, CROPPING, AND DRY WEIGHT PARTITIONING
Authors: Robinson T. L. , Stiles W. C , Lakso A. N. 
Published: February 2019

In two field studies with `Redchief Delicious'/MM.106, 'Empire'/M.9/MM.106 and 'Mutsu'/M.9/MM. 106 trees on fertile silt loam soils, trickle irrigation increased vegetative growth during the first three years and resulted in a 16%-20% increase in cumulative yield over the first five years. When fertilizer was injected into the irrigation water weekly from mid-April until the end of June, tree growth was further increased and cumulative yield was improved an additional 11%-15% for a total of 27%-35% greater yield than the non-irrigated trees. In these studies, ground fertilization did not improve growth or yield unless trickle irrigation was also applied. However, ground fertilization was not as effective as fertigation.
Irrigation and fertigation increased the dry weight of roots by 23% and that of shoots by 36% in the first year resulting in a 10% reduction in the root/shoot ratio. Total tree dry weight was increased by 30% if trees were planted early (April 14) but only 14% if trees were planted late (June 10).
Early planting resulted in 17% greater cumulative yield than trees planted late. Initial tree caliper also had a significant effect on early growth and yield with large caliper trees yielding 12% more than the small caliper trees. The interaction of planting date, tree caliper and fertigation resulted in a 50%-70% increase in yield during the first five years.