bluuebunny/crossref_metadata_2025 huggingface dataset:
200 Comparison of Spinach Growth and Development Under Broad- and Narrow-spectrum Lighting Sources
Authors: Goins Gregory D. , Yorio Neil C. , Lewis Lynn V.
Published: February 2019

Various electric lamp sources have been proposed for growing plants in controlled environments. Although it is desirable for any light source to provide as much photosynthetically active radiation (PAR) as possible, light spectral quality is critical in regard to plant development and morphology. Light-emitting diodes (LEDs) and microwave lamps are promising light sources that have appealing features for applications in controlled environments. Light-emitting diodes can illuminate a narrow spectrum of light, which corresponds with absorption regions of chlorophyll. The sulfur-microwave lamp uses microwave energy to excite sulfur and argon, which produces a bright, continuous broad-spectrum white light. Compared to conventional broad-spectrum sources, the microwave lamp has higher electrical efficiency, and produces limited ultraviolet and infrared radiation. Experiments were conducted with spinach to test the feasibility of using LEDs and microwave lamps for spinach production in controlled environments. Growth and development comparisons were made during 28-day growth cycles with spinach grown under LED (at various red wavelengths), microwave, cool-white fluorescent, or high-pressure sodium lamps. Plant harvests were conducted at 14, 21, and 28 days after planting. At each harvest under all broad-spectrum light sources, spinach leaf growth and photosynthetic responses were similar. Major differences were observed in terms of specific leaf area and weight between spinach plants grown under 700 and 725 nm LEDs as compared to plants grown under shorter red wavelengths.
205 Non-destructive Surface Area Determination of Vegetables
Authors: Upadhyaya M.K. , Furness N.H.
Published: February 2019

Surface area of cucumbers, carrots, parsnips, and beets was determined using the following non-destructive methods: Baugerod's method, Baugerod's method with inclusion of a factor correcting for substitution of weight for volume in the formula, and a novel image analysis method. Accuracy of the methods was ascertained by comparison with a direct shrink-wrap replica method of surface area measurement. Vegetables ranged in shape from cylindrical (cucumber and carrot) to conical (parsnip and beet). No difference in accuracy among methods of surface area determination was detected for carrots or beets. Baugerod's method and the image analysis technique differed significantly from the direct shrink-wrap replica technique for surface area determination of parsnips and cucumbers, respectively. Inclusion of a correction factor in Baugerod's method did not increase the accuracy of this method for any of the vegetables. The precision and repeatability of each method was determined by repeated measures analysis. Baugerod's method lost precision and repeatability for the conically shaped vegetables. Conversely, the shrink-wrap replica method lost precision and repeatability for the cylindrically shaped vegetables. The image analysis technique was precise and highly repeatable over the range of vegetable shapes. The development of a rapid, accurate, and precise non-destructive method of surface area measurement using image analysis techniques will provide a useful tool in the physiological study of vegetable products. Applicability of such a method over a range of vegetable shapes will be of additional value.
209 Influence of Lettuce Growth with High Temperature and Low Solar Radiation Conditions
Authors: Yasuba Ken-ichiro , Furuya Shigeki , Sasaki Hidekazu
Published: February 2019

When we grow lettuce in the hot season in Japan, lettuce heads sometimes grow abnormally. In early autumn, we frequently find strange shapes of lettuce because of a projecting leaf midrib. Poorly shaped lettuce is unmarketable. We found that lettuce grew abnormally under the high temperature and low solar radiation conditions at the time of 1200 °C accumulative temperature from seeding (average temperature was >20 °C and daily total solar radiation was under 18 MJ/m2). Midribs of both good-shaped (resistance of projecting midrib) and poorly shaped cultivars projected this condition, but the symptom of the former was milder than that of the latter. So, we investigated the difference of leaf growth between good and poorly shaped cultivars using growth chambers. We set up six patterns of environmental conditions, which consisted of three patterns of temperature (30/22 °C, 24/16 °C, and 18/10 °C) and two patterns of light (4 and 2 MJ/m2). The two- to three-leaf seedlings, which were grown in the greenhouse for 27 days after sowing, were transplanted in the 250-mL pots and were carried to growth chambers. We measured width and length of each leaf 9 days after planting. Consequently, the ratio of width to length (w:l) of new leaves became low when we grew lettuce in high temperature or low light conditions. The w:l of good-shaped cultivars were higher than that of poorly shaped cultivars. Good-shaped cultivars did not grow spindly with ease on high temperature and low light conditions, like an early autumn environment. Now we will try to investigate the relationship between leaf shape and head shape on the poorly shaped conditions of some lettuce heads.
211 Storability of Dry-heat-treated Gourd Seeds
Authors: Kim Du-Hyun , Lee Jung-Myung
Published: February 2019

Even though dry-heat (DH) treatment has been widely used for inactivation of seed-borne virus in vegetable seeds, it is known that the seeds should be used within a year after the DH treatment because of the significant reduction of storage capability in DH-treated seeds. DH-treated seeds exhibited poor early germination and significantly higher percentages of abnormal seedlings produced. The final germination rate was, however, not usually influenced by DH treatment. DH-treated seeds had been stored at 20 °C up to 5 years in sealed containers with silica gel in some cultivars. Both the intact and DH-treated seed exhibited excellent germination even after 4 years of storage at room temperature. Even though the hypocotyl length was shortened in DH treated seeds of most cultivars tested, other characteristics of seedlings produced from intact and or DH-treated seeds were similar. Cultivars showed marked differences in seedling characteristics, especially in length of hypocotyles.
217 Phytotoxic Effects of Different Insecticides, Doses, and Application Frequencies on Physiological Traits of Chili (Capsicum annum L.)
Authors: Garcia-Hernandez J.L. , Troyo-Dieguez E. , Nolasco H. , Jones H.G. , Ortega-Rubio A.
Published: February 2019

The phytotoxic effects on the physiology of chili (Capsicum annum L. cv. Ancho San Luis) caused by four different insecticides were evaluated. Three commercial mixes (methyl azinfos, methyl parathion CE720, and metamidophos 600 LM), and an active ingredient alone (methamidophos) were assayed; water was used as the control. The main goal was to evaluate the insecticide effects on chili using four different doses; the mean dose, recommended on the label of the product (R), a half one (1/2R), 1.5 times (1.5R) and twice the recommended dose (2R). Three frequencies of application were applied; once a week, twice a week, and once every other week, for 6 weeks from the beginning of flowering. Phytotoxicity was evaluated measuring the response of some physiological traits, Chlorophyll Fluorescence (CF), Leaf Temperature (LT), Transpiration (Tr), and Stomatal Resistance (SR). CF was measured by means of a portable chorophyll fluorscence meter; LT, Tr, and SR were measured using a LI-Cor Porometer. The doses and frequencies used are all common in commercial chili fields in Mexico. Results showed that phytotoxicity caused by insecticides can be an important damage factor to the plants, something that can cause reduction of yields. CF was shown to be the most sensitive variable to evaluate the phytotoxicity caused by insecticides. Fruit malformation was observed in all treatments. Chlorophyll content was reduced up to 25%, on average. The phosphorate insecticides affected the physiological parameters more drastically than the others. Results evidence the irreversible crop damage caused by excessive insecticide applications.
219 Alternative Weed Control Methods for Production of Large Container Ornamentals
Authors: File S.L. , Knight P.A. , Gilliam C.G. , Reynolds D.B. , Harkess R.L.
Published: February 2019

Non-target herbicide losses pose environmental concerns for nurseries. Therefore, the objective of this research was to determine the ability of each alternative mulch to suppress weed growth when compared to traditional chemical methods. Uniform quart liners of Lagersroemia indica × faurei `Natchez' were planted in 15-gal containers 15 June 1999, on a gravel container pad using overhead irrigation. Weed pressure was uniform. Treatments include Regal 0-0 3 G (3 lb ai/a) as a broadcast or individual container application, recycled newspaper pellets (1 inch thick), Spin-out coated recycled newspaper pellets (1 inch thick) geotextile disks (Spin-out coated), kenaf mulch, waste tire crumbles, wheat straw (2 inches thick), oat straw (2 inches thick), cereal rye straw (2 inches thick), paper mill sludge (2 inches thick), a handweeded control, and a weedy control. Treatments were organized in a RCBD consisting of eight single-plant replicates. The geotextile disks, newspaper pellets treated with spin-out, and shredded rubber tire treatments all had better than 80% weed control from 30 to 180 DAT. These alternative weed control methods can provide a good alternative to conventional weed control practices in large container-grown ornamental.
221 Preemergent Weed Control in Container-grown Herbaceous Perennials
Authors: Klett James E. , Staats David
Published: February 2019

During the 1999 season, preemergent herbicides were applied to container-grown herbaceous perennials and evaluated on the basis of weed control, phytotoxicity, and effect on plant growth. The herbicides and rates were: Oxyfluorfen + Pendimethalin (Scotts Ornamental Herbicide II) 3 and 6 lb ai/A, Napropamide (G) (Devrinol) 3 and 6 lb ai/A, Oryzalin (Surflan) 2 and 4 lb ai/A, Oxadiazon (Ronstar) 4 and 8 lb ai/A, Oxyfluorfen + Oryzalin (Rout) 3 and 6 lb ai/A, Prodiamine (Barricade) 0.65 and 1.3 lb ai/A, Pendimethalin (Scotts Ornamental Weedgrass Control) 2 and 4 lb ai/A, Trifluralin (Treflan) 4 and 8 lb ai/A. Herbicides were applied to Penstemon mexicali `Red Rocks'™, Osteospermum barberiae compactum `Purple Mountain'™, Gazania linearis `Colorado Gold'™, Agastache rupestris, Diascia integerrima `Coral Canyon'™, and Zauschneria arizonica. All plant and herbicide combinations did not result in any significant decline in plant growth. All herbicides provided good weed control.
244 Antioxidant Activity of Opuntia Cactus Pears
Authors: Kuti J.O.
Published: February 2019

Flavonoid content and antioxidant activity in peel and pulp samples of four different cactus pear fruit varieties were investigated. Major cactus fruit flavonoids were quercetin, kaempferol, and isorhamnetin. Greater amount of quercetin was found in the pulp compared with the peel samples in all varieties examined. Both kaempferol and isorhamnetin were found in at least three of the varieties (Opuntia ficus-indica; O. lindheimeri; O. streptacantha) exclusively in the peel samples. Generally, pulp tissue samples of all the cactus fruit varieties contained greater ascorbic acid, glutathione, alpha-tocopherol and beta-carotene and antioxidant activities than the peel tissue samples. Total flavonoids correlated well with antioxidant activity (r2 = 0.89). Ascorbic acid had the highest antioxidant activity, followed by glutathione, beta-carotene, and alpha-tocopherol on equimolar basis.
248 Influence of Early Rowcover Removal and Supported Rowcovers on Yield, Earliness, and Fruit Size of Strawberries Grown under Plasticulture
Authors: Nitzsche Peter , Fiola Joseph
Published: February 2019

Growers in Northern New Jersey are slowly adopting strawberry plasticulture as an improved production system. One advantage of the system is early fruit production. Early fruit usually brings high prices in the marketplace. With early production, however, there is an increased risk of a late frost damaging flowers and fruit. Removing floating rowcover winter protection earlier than flowering may cause strawberries to bloom later, reducing the risk of frost damage. Supporting the rowcovers above the crop with wire hoops may also provide better winter protection and improve fruit production. In 2 years of field trials, removing floating rowcovers 2 weeks before anticipated bloom reduced early yield and delayed the first harvest by 2 to 3 days. Total marketable yield and average fruit weight were not significantly influenced by early removal. Plants with rowcovers supported with wire hoops did not produce significantly greater total yields or average fruit weights than plants protected by unsupported rowcovers. The wire hoops caused damage to the rowcovers, which may make their use in commercial production impractical.
251 Humic Acid Substrate Treatments and Foliar Spray Application Effects on Root Growth and Development of Seedlings
Authors: Li Gang , Evans Michael R.
Published: February 2019

Seedlings of Cucumis sativus (cucumber), Tagetes patula (marigold), Viola tricolor (pansy), Pelargonium × hortorum (geranium), and Impatiens wallerana (impatiens) were germinated on towels soaked with either deionized water, nutrient control solutions, or humic acid solutions. Root fresh weight and root dry weights were higher for all seedlings germinated on towels soaked with humic acid as compared to seedlings germinated on towels soaked with deionized water or nutrient control solutions. Lateral root number and total lateral root length were higher for cucumber, marigold, pansy, and geranium seedlings germinated on towels soaked with humic acid than those germinated on towels soaked with deionized water or nutrient control solutions. Root fresh and dry weights were higher for impatiens, Begonia semperflorens (begonia), marigold, and geranium seedlings germinated in a sphagnum peat: vermiculite (80:20, %v/v) substrate drenched with humic acid as compared to seedlings germinated in substrate drenched with deionized water or nutrient control solutions. Foliar sprays of humic acid also resulted in increased root fresh and dry weights while foliar application of nutrient control solutions either had no effect or reduced root fresh and dry weights.
257 Characterization of the Physico-chemical Properties of and Plant Response to Ecologically Sound Organic Substrates in Relation to Rockwool
Authors: Islam Md. Shahidul , Ito Tadashi
Published: February 2019

Characterization of physico-chemical properties of ecologically sound unprocessed coconut (Cocos nucifera L.) coir and carbonated rice husk in relation to rockwool were investigated to examine the crop performance along with productivity of tomatoes (Lycopersicon esculentum Mill.). In all substrates, the water-filled pore space and water-holding capacity were larger and air-filled pore space was smaller. Bulk densities, water-holding capacity, and water-filled, air-filled, and total pore spaces were lower in carbonated rice husk than coconut coir and rockwool. These values in coconut coir and carbonated rice husk were increased by use. Most of the physical properties, EC, pH, and inorganic elements, of these natural organic substrates were within appropriate levels as growing media. There were little differences in plant height, stem diameter, percent fruit set, harvest index, ascorbic acid, total soluble solid, fruit pH, and leaf chlorophyll ratio. But, number of nodes, internode length, leaf number and area, days to first anthesis, flower number, and fruit number and weight differed significantly among treatments. There was smaller fluctuation in absolute growth rate, relative growth rate, net assimilate rate, and leaf area ratio among the treatments. It appeared that carbonated rice husk and the coconut coir gave better crop performance than rockwool under moderate high temperatures (30 and 35 °C compared to 25 °C). Furthermore, crop productivity from the organic substrate coconut coir and carbonated rice husk gave more profit than that of rockwool. Thus, carbonated rice husk and coconut coir substrates can be used successfully as a bag culture media amendment for producing vegetables, especially in tropical and subtropical areas.
261 The Response to Photoperiod Varies in Closely Related Cultivars of Dwarf Carnation
Authors: Karlsson Meriam , Werner Jeffrey
Published: February 2019

Dwarf carnation (`Monarch Yellow' and `Monarch Purple') was germinated and grown at 20 °C for 3 weeks. Following transplant (21 d from seeding), seedlings were grown at 16 °C and either 9 or 16 hr daylength. Irradiance was adjusted to 10 mol/m2 per day. Growth and development in response to photoperiod was significantly different for the two cultivars in the `Monarch' series. Flowering at long days was faster with 118 d from seeding for `Monarch Yellow' and 128 d for `Monarch Purple'. Under short days, flowering was observed 128 d from seeding in `Monarch Yellow' and 144 d for `Monarch Purple'. Ten days with short photoperiod initiated at transplant followed by long days resulted in more branching without significantly delayed development for `Monarch Yellow'. No effect on branching or rate of development was observed in `Monarch Purple' with 10 initial short days compared to long days throughout.
277 Effect of Pruning Method on Yield and Quality of `Sunbelt' Grapes Grown in the San Joaquin Valley of California
Authors: Striegler R. Keith , Morris Justin R. , Main Gary L. , Lake Chris B. , Graves Simon R. , Threlfall Renee T. , Blevins Janice M.
Published: February 2019

`Sunbelt' is a juice grape cultivar developed by the Univ. of Arkansas. This cultivar produces `Concord'-type juice and is adapted to climatic conditions of the southern United States. Preliminary evaluation showed that `Sunbelt' has potential to produce high-quality juice under the hot climatic conditions of the San Joaquin Valley. A study was conducted during the 1998 and 1999 seasons to further evaluate the adaptation of `Sunbelt' to San Joaquin Valley conditions and determine the response of this cultivar to selected pruning methods. Vines of uniform vine size and vigor were subjected to four pruning treatments: severe hand-pruning (60 to 80 nodes retained/vine); moderate hand-pruning (120 to 160 nodes retained/vine); machine-pruning (160 to 180 nodes retained/vine); and minimal pruning (200 to 400 nodes retained/vine). Vines were trained to a Geneva Double Curtain trellis system. Yield and components of yield were significantly impacted by pruning treatment. In both seasons, mechanized systems of pruning (machine or minimal) produced higher yield than hand pruning. Minimal pruning resulted in the highest yield in 1998, while yield from machine-pruned vines was highest in 1999. Minimally pruned vines had the highest clusters/vine, lowest cluster weight, and lowest berry weight among the treatments. Fruit composition was also affected by pruning treatment. Minimal pruning produced fruit which was less mature than fruit from the other treatments in 1998. This result was likely due to the high yield obtained. Few differences in fruit composition were observed among treatments in 1999. The effect of pruning method on processed juice quality will be presented. Acceptable juice quality was obtained for most treatments.
283 Water and Nutrient Management of Garlic in California
Authors: Voss Ronald , Cantwell Marita , Hanson Blaine , May Donald , Rice Robert
Published: February 2019

Garlic is a cool-season vegetable crop with a long growing season. The potential nutrient and water needs are high. Irrigation and fertilization trials were conducted in the San Joaquin Valley in varying weather and different soils. Objectives were to relate fertilizer and irrigation management to garlic yield and to the efficiency of water and fertilizer use;to develop crop coefficients relating crop ET to reference crop ET; to relate postharvest quality to water nutrient management; and to determine if slow-release nitrogen fertilizers are as effective as more soluble forms. N, P, and K rates and timing of applications were applied. Furrow irrigation variables included calendar timing, cutoff date of last irrigation, irrigation at different available soil moisture (ASM) depletion, and irrigation based on evapotranspiration. A line source sprinkler irrigation was also conducted. Response to fertilizer nitrogen and to irrigation were dependent on soil type and depth. Response in heavy, deep soil was poor; response in lighter texture and shallower soil was much greater. Garlic extracted water and nutrients to depths greater than 120 cm and suffered no yield loss at high ASM depletion (50%) in deep, heavy soil. In shallow or lighter texture soil, extraction was limited to 60 cm, with highest yields when irrigated at 25% ASM depletion. Yield and quality of garlic were affected by irrigation cutoff date. Nitrogen response varied from ≈100 to more than 300 kg/ha. Slow-release nitrogen fertilizers were effective, but not economical. Little or no response to P or K fertilizer was measured in these experiments. Effects of excessive fertilizer rates on postharvest quality was variable.
285 Some Polyethylene Mulches Increase Root Numbers in Peppers
Authors: Gough R.E.
Published: February 2019

In 1999, `Sweet Banana' pepper plants were grown under clean cultivation or SMR—red, silver, or black polyethylene mulches. Plants in each of three replications per treatment were field-set on 15 June. On 22 Sept., plants were excavated, and their root systems were examined. The total number of roots per plant at 5-, 10-, 15-, 20-, and 25-cm depths and 10-, 20-, 30-, 40-, 50-, and 60-cm distances from plant stems were recorded. Distribution and architecture of the root systems also were examined. Plants grown under clean cultivation developed 50 to 60 adventitious roots each, while those grown under red mulch developed about 20, and those under black and silver mulch about nine adventitious roots each. In all treatments, the adventitious roots radiated from the stem at an oblique, downward 35° angle. No plants had vertical roots. Root system architecture was similar among treatments, with 40% of the roots in the upper 5 cm of soil and 70% in the upper 10 cm. Thirty percent of roots were within 10 cm of the plant stem, and 50% were within 20 cm. Nearly 100% of the roots were located within 40 cm of the plant stem. Root count decreased with increasing depth and distance from the plant stem. Plants grown beneath the silver mulch produced the greatest number of lateral roots, followed by plants grown in clean cultivation and under black mulch. Plants grown under red mulch produced the fewest roots. Differences among treatments were significant. Colored mulches influence the total number of adventitious and lateral roots but not the root system architecture of pepper plants.
291 Light-filtering Film Reduces Tomato Seedling Height Without Altering Fruit Quality and Yield
Authors: Evans William B. , McMahon Margaret
Published: February 2019

There is significant interest in using non-chemical methods to control seedling height in vegetable transplant production. One method being evaluated is the use of greenhouse films that filter signifcant amounts of far-red light from ambient light, resulting in shorter tranplants. This study was undertaken to evaluate fruit yield and quality of field-grown tomatoes produced from seedlings grown under light-filtering plastics. Tomato seedlings were grown under clear polyethylene tents or light-filtering laminate tents in a polyethylene-covered Quonset greenhouse in northern Ohio. Standard 288 deep plug trays, filled with MetroMix 360, were used. Seedlings were placed under the tents at the cotyledon stage and transplanted 28 days later. Once in the field, they were grown as staked plants under open conditions using locally accepted horticultural practices. Differences in seedling height were detected within a few days after being placed under the tents. Compared to those grown under clear polyethylene tents, seedlings grown under the light-filtering plastic increased in height more slowly and were shorter at transplanting. At harvest, within each of the three cultivars tested, no significant differences in fruit number, yield, or mean fruit size were found between treatments. It is inferred that this non-chemical method for reducing vegetable transplant height may be a viable production option in the future.
297 Study of the Regular and High Application of Water with Drip Irrigation in Asparagus
Authors: Fontes Adán Fimbres , Contreras Raúl Leonel Grijalva
Published: February 2019

Asparagus production in the past years has been increasing very rapidly and now totals 5000 ha. The main problem in this zone is the depletion of the aquifer and it is important to use this resource carefully. During 1999, an experiment of drip irrigation in asparagus was conducted. Three treatments were applied: 50%, 75%, and 100% of the evaporation from a pan evaporation type A. The results of the statistical analysis indicated that the best treatment was 100% with a yield of 517 boxes/ha and 183 cm of water applied. The lowest yield (290 boxes/ha) was with 50% and 91 cm of water applied.
312 Influence of BAP and CPPU on the in Vitro Shoot and Bud Proliferation of Apple Rootstocks M.111 and M.7
Authors: Nesi Adriano N. , de L. Fortes Gerson R. , da Silva Jono B. , de M. Dantas Adriana C.
Published: February 2019

This work aims to verify the effect of BAP (6-benzyladenine purine) and CPPU (forchlofenuron) on the in vitro shoot proliferation of apple rootstock cultivars M.111 and M.7 under different concentrations. The experiment was carried out in the tissue culture laboratory at Embrapa Temperate Climate in Pelotas, RS, Brazil. As initial explants, microcuttings were used from in vitro culture. The treatments consisted of the combination of two cultivars with cytokinins and six differents concentrations (0.0, 1.5, 3.0, 4.5, and 6.0 μMol). The explants were inoculated in 250-mL flasks with 40 mL MS medium with agar (7.0 g·L-1), myo-inositol (100.0 g·L-1), NAA (0.005 mg·L-1), and sucrose (40.0 g·L-1). The pH was adjusted to 5.9 before autoclaving. After inoculations the culture was kept for 50 days under 25 ± 2 °C, 16-h photoperiod, and 19 μMol·m-2·s-1 radiation. CPPU performed better than BAP for cultivar M.111 and it had similar response for cultivar M.7 as bud and shoot multiplication and multiplication rate is concerned. The BAP increased the number of shoots with higher length and with no callus formation in the shoot base, contrary to CPPU. The most efficient concentrations were 4.7 and 5.5 μMol for CPPU and BAP, respectively.
313 In Vitro Shoot Multiplication of Adult Black Walnut (Juglans nigra L.)
Authors: Pearson Susan , Preece John E. , Van Sambeek J.W.
Published: February 2019

During Apr. 1999, the lower branches of mature black walnut trees were removed and cut into sections 48 cm long and placed horizontally in plastic flats filled with perlite in a shaded polyethylene-covered greenhouse. Water was applied by drip emitters and care was taken to avoid overhead water contact with the stem sections. Within 2 months, elongating, green, leafy shoots were excised, brought into the laboratory, surface disinfested and placed in vitro onto agar-solidifed Long and Preece (LP) medium with 0.3 μM thidiazuron (TDZ), 0.5 μM indolebutyric acid (IBA), and either 0.1, 1.0, or 10.0 μM benzyladenine (BA). Explants were transferred to fresh medium after 1, 3, and 5 days in vitro and every 2 weeks thereafter. After 3 months in vitro, callus was excised and and explants were all placed on LP medium with 10 μM BA and 0.5 μM IBA for 4 weeks. They were then transferred to LP with 0.3 μM TDZ, 1.0 μM BA, and 0.5 μM IBA for 2 weeks. This 4-2-week alternation of media has continued for more than 6 months. After 4 months in vitro, shoot clusters were subdivided, and individual microshoots recultured. Of the original 260 explants, 30 survived and have been subdivided into 111 cultures. These explants have produced 132 axillary shoots that are also multiplying. Adult black walnut will acclimate and proliferate in vitro, but only with careful attention to detail and regular transfers to fresh medium.
320 Lupinus albus ssp. graecus L., A Native Plant with Potential for Floricultural Use
Authors: Vlahos J.C. , Ververidis P.
Published: February 2019

Lupinus albus ssp. graecus, L. Fabaceae (Boiss. and Spruner) Franco and P.Silva, is being studied at the TEI of Heraklion since 1998 as a new plant with potential use in floriculture and ornamental horticulture. The plant has been recorded botanically; however, little is known about its physiology and genetic profile. Lupinus albus ssp. is a herbaceous annual plant 10 to 20 cm tall, growing at roadsides, field margins, vineyards, and olive groves up to 700 m altitude. The leaves are 5 to 11 cm wide, palmate shaped in alternate orientation, with five to nine leaflets 10 to 18 mm wide, all arising from the same point. The flowers are borne in terminal or lateral spike-like racemes 10 to 20 cm long. Florets are 15 mm long, dark blue occasionally with a white patch, stamens forming a tube. Pods are 60 to 70 mm long,with four to six black-spotted seeds. In the present work, seed germination studies were conducted combining chilling pretreatments with physical scarification (scratching). Mature seeds chilled at 5 °C for 6 weeks germinated readily (83%) when scarified with sand paper. Furthermore, we tested the effects of several plant growth regulators (chlorocholine chloride, paclobutrazol, maleic hydrazide and Ethrel 48) on young plants of Lupinus in order to obtain compact pot plants with more flowering racemes. Paclobutrazol at 5 and 10 mg/L achieved the best retardation effect, but did not affect flowering. In another trial with different potting media,the commercial potting soil proved the most suitable for growing lupins satisfactorily. It is concluded that Lupinus albus spp. graecus L. need further investigation in order to establish the best cultural conditions for its growth and development. Furthermore, due to its high genetic variability, selection and genetic improvement is required for optimal results.
322 In Vitro Propagation of the Ornamental Bromeliad, Tillandsia eizii
Authors: Pickens Kimberly A. , Wolf Jan , Affolter James M. , Wetzstein Hazel Y.
Published: February 2019

Many bromeliad species indigenous to the rain forests of Central and South America are threatened because of over-collection and habitat destruction. Studies were conducted to develop propagation protocols for Tillandsia eizii, a rare ornamental bromeliad of ceremonial significance to the Highland Maya communities in Chiapas, Mexico. We anticipate using in vitro propagation for the conservation of this species with the potential of utilizing bromeliads as an alternative and sustainable forest resource. Protocols were developed for the sterilization and germination of axenic seed. Seedling growth in vitro was assessed and outplanting studies were conducted. Media were evaluated to promote adventitious bud production in experiments using the plant growth regulators naphthaleneacetic acid and benzylaminopurine. Pulse time and duration, as well as the stage of seed development, had a marked effect on bud production. The effects of various potting media on plant growth and survival were assessed. A pure pine bark medium elicited over 95 percent survival. Plants exhibited a “tank-like” morphology characteristic of plants in the wild.
327 Hydroponic Minituber Production
Authors: Lowe R. , Donnelly D.
Published: February 2019

Minituber production was investigated using ex vitro `Norland' plantlets in a rockwool-based hydroponic system. Productivity was evaluated for 12- and 16-h photoperiod pre-treatment, planting density (two, four, and six plantlets/slab), vertical or horizontal orientation, pinching, and hilling. Total yield differences did not result from photoperiod pre-treatments, but 12-h pre-treatment increased the number of minitubers in the desirable 10- to 40-g size range. Increased planting density reduced yield per plant but caused small increases in yield per slab. Planting orientation, pinching, or hilling had no effect on overall fresh weight yield, number, or size distribution. Short photoperiod pre-treatment, and planting densities of four to six plantlets/slab, oriented vertically, are recommended.
333 Micropropagation of Echinacea angustifolia, E. pallida, and E. purpurea from Vegetative and Seed Explants
Authors: Harbage James F.
Published: February 2019

Micropropagation of three Echinacea species, E. angustifolia, E. pallida, and E. purpurea, was investigated as a potential means of germplasm preservation of species faced with overcollection in the wild and rapid clonal propagation of elite individuals with unique medicinal or ornamental properties. Comparison of explant sources indicated vegetative explants resulted in high contamination rates when collected from shoot-tips (100%),but not when collected from nodal explants (11% to 39). Seed coat removal reduced contamination from 100% in intact seeds to near 0% in excised embryos. Removal of seed coats (pericarp and integument layers) also eliminated dormancy requirement for germination. All species responded with shoot multiplication and loss of rooting when BA or thidiazuron was added to culture medium. Medium with thidiazuron resulted in excessive adventitious shoot formation. Shoot multiplication rates were low (one to three shoots/explant) on medium with BA levels low enough to avoid adventitious shoot formation. Medium containing half-strength MS minerals resulted in more shoots with smaller leaves than full-strength MS minerals. Cultures did not perform well on Woody Plant Medium. Increasing subculture frequency from every 4 weeks to every 2 weeks increased shoot multiplication rates from 1.4 to 1.8 shoots per subculture and total shoots produced after 12 weeks of culturing (per initial explant) from 2.8 to 23.9. Rooting occurred readily on shoots isolated from E. purpurea without addition of IBA. Rooting was low or non-existent on shoots from E. angustifolia and E. pallida, respectively, regardless of IBA level, light conditions, or temperature. Methods described in this study allow rapid multiplication of three Echinacea species and subsequent rooting of E. angustifolia and E. purpurea. Future improvements in root induction treatments will allow more effective use of micropropagation for Echinacea germplasm preservation and multiplication. Chemical names used: N-(phenylmethyl)-1H-purine-6-amine (BA), 1H-indole-3-butyric acid (IBA).
335 Light Exposure and Gibberelic Acid Effects on Common Carpetgrass (Axonopus affinis Chase) and Centipedegrass [Eremochloa ophiuroides (Munro) Hack.] Seed Germination
Authors: Bush Edward , Wilson Paul , McClure Gloria
Published: February 2019

A study to determine the influence of light duration on seed germination was performed in a temperature-controlled growth chamber. Light treatments consisted of 0 (control), 6, 8, 10, 12 and 14 h of light exposure. Cool fluorescent light bulbs provided 19 μMol·m-2·s-1 light. Fifty seeds of each treatment were placed into separately labeled 6.0-cm-diameter petri dishes lined with Whatman #42 filter papers moistened with 2 mL of distilled water. Seed of both species germinated poorly in the control treatment. Mean time of germination (MTG) and germination percentage increased for both species when seeds were exposed to light. Pre-soaking seed in gibberellic acid (GA) significantly improved germination percentages of both species compared to the untreated control. Centipedegrass germination percentage and MTG also increased with light exposure. Carpetgrass seed germination was not enhanced by GA treatments with light exposure. The results of this experiment suggests that, if seed are covered too deeply, excluding light, MTG and percentage germination will be reduced. However, pre-soaking seed in a GA solution can improve dark germination by as much as 50% for both grass species.
341 Overcoming Seed Dormancy in Winecups, Callirhoe involucrata
Authors: Oakley Dianne , Laufmann Julie , Klett James , Hughes Harrison
Published: February 2019

Propagation of Winecups [Callirhoe involucrata (Torrey & A. Gray)] for use as a landscape ornamental has been impeded by a lack of understanding of the seed dormancy and a practical method for overcoming it. As with many members of the Malvaceae family, C. involucrata produces hard seed. In the populations tested, it accounted for 90% of an average sample. Impermeability, however, is not the only limiting factor to germination. Three disparate populations of seed, representing two different collection years have been investigated using moist pre-chilling, boiling water, leaching, gibberellic acid, hydrogen peroxide and mechanical and chemical scarification methods. Scarifying in concentrated sulfuric acid stimulates germination of some seed fractions and causes embryonic damage in others, suggesting variation in seed coat thickness. Similar results were obtained using a pressurized air-scarifier; the hard seed coat of some seed fractions were precisely scarified while others were physically damaged using the same psi/time treatment. Placing seed in boiling water increases germination from 4%, 7%, and 18 % to 23%, 25%, and 77% in the three populations, respectively. Leaching for 24/48 h in cold (18 °C) aerated water or for 24 h in warm (40 °C) aerated water showed only a minor increase over the control. Pre-chilling at 5 °C for 30, 60, and 90 days showed no improvement over the control. Gibberellic acid-soaked blotters improved germination at 400 ppm to 20%, 10%, and 41%; at 500 ppm germination was reduced. Soaking seed for 24 h in a 3% concentration of hydrogen peroxide did not effect germination; at a 30% concentration germination was reduced. The considerable variation in seed dormancy expression may be a function of differences in environmental factors during development or seed age.
345 Incorporation of Slow-release Fertilizer Accelerates Growth during Adventitious Rooting of Artemisia, Gaura, and Nepeta
Authors: Rowe D. Bradley
Published: February 2019

Accelerating growth of nursery stock can produce marketable plants in less time, thus potentially increasing profits. The primary objective of this study was to compare adventitious rooting and initial growth of cuttings of three perennials species in response to slow-release fertilizer incorporated into the propagation media. The experiment was a split-plot consisting of four blocks, nine nutrient treatments, three species, and four cuttings per replication within each block-nutrient, species treatment. Treatments consisted of Nutricote 13-13-13 Type 180 and Nutricote 18-6-8 Type 180 incorporated into the rooting media, each at 3, 6, 9, and 12 g·L-1, and a control with no Nutricote. Species studied were Artemisia ludoviciana `Valerie Finnis', Gaura lindheimeri `Whirling Butterflies', and Nepeta ×faassenii `Six Hills Giant'. There were of 144 cuttings per species for a total of 432 cuttings. Fertilizer treatments did not influence rooting percentage, and no significant differences were found between the two formulations of fertilizer for top growth, root growth, rooting percentage, or root number. However, regardless of formulation or rate, the eight fertilizer treatments resulted in greater top and root dry weights when compared to the control. Top and root dry weight increased linearly within both fertilizer formulations.
347 Rooting of Softwood Cuttings from Dormant Woody Stems Forced in a Forcing Solution Containing Silver Thiosulfate and Gibberellic Acid
Authors: Hamooh Bahget T. , Read Paul E.
Published: February 2019

Research was conducted in Feb. 1999 to study the effects of including silver thiosulfate (STS), gibberellic acid (GA3), or both in the forcing solution on rooting of softwood cuttings produced by forced dormant woody plant species. The cuttings were dipped for 10 s in 2000 ppm indole-3-acetic acid (IAA) or 2000 ppm indolebutyric acid (IBA). High percentages of rooting were observed in the two woody plant species examined. Root number and length of the new growth of Cornus alba and Euonymus alatus forced in a forcing solution containing the basic forcing solution treatment (8-HQC at 200 mg·L-1 + 2% sucrose), the STS treatment, or the combination treatment of STS + GA3 were not significantly different. However, treating the dormant stems of the two woody plant species examined in a forcing solution containing only GA3 led to fewer and shorter roots when compared to all other treatments. Applying either IAA or IBA to the new softwood growth led to similar root length and number for both species. This forcing solution approach provides an attractive alternative for propagating woody plants during winter months.
388 Extension Water Quality Training for the Nursery Industry
Authors: Schnelle Michael A. , von Broembsen Sharon L. , Smolen Michael D.
Published: February 2019

A comprehensive educational program focusing on water quality protection was developed for the Oklahoma nursery industry. The program focused on best management practices to limit pesticides and nutrients in irrigation runoff and on capture and recycle technology as a pollution prevention strategy. Key professionals from the departments of entomology and plant pathology, biosystems and agricultural engineering, and horticulture formed a multidisciplinary team within the Oklahoma Cooperative Extension Service (OCES). During 1998, water quality workshops were conducted on-site throughout Oklahoma at leading nursery operations. These workshops were designed to highlight best management practices (BMPs) that were already in place as a foundation on which to implement additional BMPs with the assistance of the OCES team. Training workshops were augmented by written publications, by web-based information, and by videotape instruction. These provided for ongoing education beyond the formal grant period. The written materials included a water quality handbook for nurseries and a fact sheet on capturing and recycling irrigation runoff. The water quality handbook was also made available on the web and a website on disease management for nurseries using recycling irrigation was provided. The water quality video, highlighting successful growers, was designed to show aspects of both best management practices and capture and recycle technology. Results of these 3-year extension efforts will be discussed.
390 Feasibility of Solar-powered Irrigation for Remote Areas
Authors: Tietjen W.H. , Grande J. , Nitzsche P.J. , Manning T. , Dager E.
Published: February 2019

Remote areas of the United States and developing nations depend on either electric grid extension or diesel power for operating crop irrigation systems. However, electric grid extension is expensive and often impractical. Diesel pumps are expensive, polluting, and require maintenance to operate. Utilizing the energy of the sun, captured by photovoltaic panels, to power irrigation systems offers a cost-effective, pollution-free, and maintenance-free alternative. Solar-powered pumping systems are capable of delivering water from rivers or wells in volumes up to 2000 gal/min. Combining solar power with drip irrigation takes advantage of the natural coincidence of peak energy from the sun and the crop's peak need for water. In 1999, cabbage was grown comparing solar and conventionally powered drip irrigation systems at the Rutgers Univ. Snyder Research and Extension Farm, Pittstown, N.J. The solar system was operated by a 1.5-horsepower motor powered by 18 solar modules.
403 Butternut Squash (Cucurbita moschata) Yield and Soil Erosion in Three Tillage Systems
Authors: Infante-Casella Michelle L. , Garrison Steven A.
Published: February 2019

Many squash varieties are large-seeded and may be well-suited for planting under no-till production systems. A study was done at the Rutgers Agricultural Research and Extension Center in Bridgeton, N.J., to evaluate the yield and loss of soil when butternut squash (BS) (Cucurbita moschata `Waltham') was grown using no-till (NT), strip-till (ST), and bare ground (BG) tillage systems. The soil was a Sassafrass gravely sand loam and the field had a 3% slope. A cover crop mixture of hairy vetch and winter rye planted on 23 Sept. 1998 using a Brillion seeder at a rate of 136.2 kg/ha and 610.2 kg/ha, respectively, was used to create the NT and ST plots. NT and ST plots containing the cover crop mixture were killed with Glyphosate and chopped using a Buffalo stalk chopper on 27 May. BG plots were tilled clean before planting and ST plots were rototilled to a 30.48 cm band to establish a seedbed. BS seeds were hand-planted on 7 July with a spacing of 38.1 cm between plants and 182.9 cm between rows. Irrigation was applied overhead at a rate of 6.28 cm/ha weekly. Erosion was measured using inverted pans over the soil area to be measured. Harvest took place on 21Oct. and yields included only marketable fruit with the following results: NT = 8.65 t/ha; ST = 8.99 t/ha; BG = 4.06 t/ha. Yields in the NT and ST plots were significantly higher than yields in the BG plots. Soil erosion measurements were taken on 21 Oct. Soil loss results from the plots were 0.08 cm (NT), 0.84 cm (ST), and 3.33 cm (BG). Soil loss, mainly due to water erosion, was significantly higher in the BG plots. BS yields can be significantly higher when using alternative tillage systems like NT and ST. When using NT and ST systems for the production of BS, soil erosion is reduced
404 Cowpea Cover Crop Mulch Controls Weeds in Transplanted Bell Peppers
Authors: McGiffne Milton E. , Hutchinson Chad
Published: February 2019

A 2-year field project was conducted in Thermal, Calif., on cowpea (Vigna unguiculata) mulch as an alternative weed control option in pepper (Capsicum annuum) production. Treatments included a bare ground production system with hand weeding, bare ground with no weeding, a cowpea mulch production system with hand weeding, and cowpea mulch with no weeding. Cowpea was seeded in July in 76-cm beds and irrigated with a buried drip line. In September, irrigation water was turned off to dry cowpea plants. The cowpea plants then were cut at the soil-line to form mulch. Pepper plants were transplanted into mulch and fertilized through the drip line. Every 2 weeks, the number of weeds emerged and pepper plant heights were recorded. In December, fruit production, pepper plant dry weight, and weed dry weight were recorded. Fewer weeds emerged in the cowpea mulch than the conventional bare ground system. At harvest, weed populations in nonweeded cowpea mulch were reduced 80% and 90% compared to nonweeded bare ground for 1997 and 1998, respectively. Weed dry weights in nonweeded treatments were 67% and 90% less than weed dry weights in nonweeded bare ground over the same period. Pepper plants in cowpea mulch produced 202% and 156% more dry weight than on bare ground in 1997 and 1998, respectively. Pepper plants in cowpea mulch produced more fruit weight than in bare ground with similar fruit size. Cowpea mulch provided season-long weed control without herbicides while promoting plant growth and fruit production.