bluuebunny/crossref_metadata_2025 huggingface dataset:
(222) The Residual Effect of Organic Amendment Applications on the Yield of Sweet Corn, Zucchini, and Mustard Cabbage
Authors: Valenzuela Hector , Corrales Roger , Goo Ted
Published: February 2019

A major issue in the preparation of nutrient budgets for organic farmers is the residual nutrient effect from organic amendments available for follow-up crops in year-round rotation systems. A series of separate experiments were conducted to evaluate: 1) the residual nutrient effects on double-cropped sweet corn from initial applications of several organic amendments locally available in Oahu, Hawaii; 2) the residual effect of double cropped zucchini; and 3) mustard cabbage from the application of similar organic amendments. The sweet corn experiment consisted of six treatments, with organic amendments applied only prior to the first planting. The second follow-up sweet corn planting was grown without additional amendment applications. Treatments included: 1) a fruit fly based compost; 2) aged chicken manure; 3) bone meal; 4) synthetic fertilizer (farmer's practice); 5) a combination of compost and fertilizer; and 6) a combination of compost and chicken manure. The experiment was arranged with a randomized complete-block design. Each treatment plot consisted of two 20-m long rows of corn with five replications per plot for a total of 30 treatment plots. On a separate location similar trials were conducted on long-term organic farming plots, with double cropped zucchini and with double cropped mustard cabbage. The results from this research shows that crop yields were similar or greater under the organic amendment plots compared to the synthetic fertilizer plots. In crops with a high N uptake demand, yields from the organic amendment plots declined by about 10% in follow-up plantings. This data will allow organic farmers to prepare nutrient budgets to better match their organic fertilizer applications with crop nutrient demands.
(223) The Effect of Commercial Home Garden Fertilizers on the Growth and Yield of Two Chinese Cabbage Varieties
Authors: Valenzuela Hector , Goo Ted , Uchida Ray , Migita Susan
Published: February 2019

Home gardening is a popular year-round recreational activity in Hawaii that helps to increase community food security in suburban and rural communities where high levels of poverty and unemployment exist. Updated fertilizer recommendations and accurate information about the latest products allows home gardeners to improve crop growth, and to minimize nutrient imbalances in the soil, pest problems, and environmental risks from nutrient runoff or leaching. Two field experiments were conducted in Oahu, Hawaii, to evaluate several new products in the market for the production of two home-garden Chinese cabbage varieties. The treatments included Miracle Grow, a new Miracle Grow Plus formulation, Plant Power 2003 nutrient solution, a Maui Liquid Compost product, and a standard fertilizer control (150 kg·ha-1 N rate). Each treatment consisted of a 6-m long row with 30-cm plant spacing in the row. Each treatment was replicated four times in a completely randomized block design, for a total of 40 plots (two varieties × five treatments × four replications). Data collected included soil fertility before initiation and after experiment completion, tissue nutrient analysis, plant height collected twice during the growing cycle, and head weight and length measured at harvest time. The variety Pagoda was more responsive to fertilizer applications, showing an average of 30% yield increases between the best and poorest treatment, compared to 20% for `China Express'. Overall, the Miracle Grow formulations outperformed the other products. The tissue nutrient data showed tissue nutrient levels above those recommended by the Extension Service. The treatments with highest yield response also showed greater symptoms of “black heart” from possible boron deficiency.
(225) Challenges and Opportunities with Vegetable BMPs in Southwest Florida
Authors: Ozores-Hampton Monica , Simonne Eric , McAvoy Eugene , Stansly Phil , Shukla Sanjay , Roberts Pam , Roka Fritz , Obreza Tom
Published: February 2019

About 10,000 ha of staked tomato are grown each year in the winter–spring season in southwest Florida. Tomatoes are produced with transplants, raised beds, polyethylene mulch, drip or seepage irrigation, and intensive fertilization. With the development of nutrient best management practices (BMPs) for vegetable crops and increased competition among water users, N recommendations must ensure economical yields, but still minimize the environmental impact of tomato production. The current University of Florida–IFAS (UF–IFAS) N fertilization rate of 224 kg·ha-1 (with supplemental fertilizer applications under specified conditions) may require adjustment based on soil type and irrigation system. Because growers should be involved in the development and implementation of BMPs, this project established partnerships with southwest Florida tomato growers. Studies evaluated the effects of N application rates on yield, plant growth, petiole N sap, pests, and diseases. Nine on-farm trials were conducted during the dry winter 2004–05 season. Treatments consisted of N fertilizer rates ranging from 224 to 448 kg·ha-1, with each trial including at least the UF–IFAS rate and the traditional rate. Although total yields were comparable among N rates, there were differences in size category. Nitrogen rates had little effect on tomato biomass 30 and 60 days after transplanting. Changes in petiole sap NO3-N and K concentrations were different between seepage and drip irrigation, but usually above the sufficiency threshold. It is important to consider the type of irrigation when managing tomato and determining optimum N fertilizer rates.
(226) Tomato Cultivar Differences in Ion Uptake and Growth in Closed Hydroponic Culture
Authors: Kim Hyung Jun , Harlow Chris , Peet Mary
Published: February 2019

The objective of this study was to compare nutrient ion uptake and growth of Lycopersicum esculentum Mill. cvs. Trust, widely grown in North America, and Momotaro, widely grown in Korea and Japan. Tomatoes were planted July 2004, two per pot, in 36 perlite-filled pots fertigated with modified Steiner solution in a closed system. Inorganic ions (K, NO3-N, Mg, P, S) in the nutrient solution were measured weekly. Weekly solution uptake rate for both cultivars increased from 70 mg·MJ-1 irradiance at 36 days to 200 mg·MJ-1 at 133 days (end of experiment). The uptake rate of `Trust' was lower than `Momotaro' until 92 days after planting, then higher for the remainder of the experiment. This corresponded to lower leaf area in `Trust' prior to 92 days, then greater leaf area than `Momotaro'. Similarly, the nutrient uptake rate (ppm) of K, Ca, Mg, and S ions in `Trust' were lower than `Momotaro' until 92 days and higher after 92 days. The P uptake showed the opposite pattern with a higher uptake rate in `Trust' than `Momotaro' until 92 days and lower uptake thereafter. The N uptake rate did not differ between the cultivars. Thus, except for P and N, uptake of individual ions was proportional to total nutrient solution uptake. Plant height, number of clusters and total leaf area at 133 days was higher in `Momotaro' but fruit number and total aboveground dry weight (leaf, stem, and fruit) was higher in `Trust'. Percentage of total dry weight, represented by leaf and fruit in `Momotaro', were 40% and 41%, respectively, and 30% and 57%, respectively in `Trust'.
(431) Evaluation of Anti-transpiration Organic Materials on Strawberry Performance
Authors: Kadir Sorkel , Ennahli Said , Glass Ben
Published: February 2019

Interactive effects of different temperature regimes and anti-transpiration organic materials, Surround WP (kaolinite clay) and Raynox (sun-protectant), on two strawberry (Fragaria ×ananassa) cvs. Chandler and Sweet Charlie were investigated under controlled environmental conditions. Newly planted strawberries treated with Surround and Raynox were subjected to 20/15, 30/25, and 40/35 °C (day/night) temperature regimes and 16 day/8 night photoperiod in growth chambers for 42 d. Photosynthesis (A) and photochemical efficiency (Fv/Fm) were measured at 7-d intervals during the experiment. Plants treated with Raynox displayed greater resistance to high temperature (40/35 °C) compared to those treated with Surround. Net photosynthesis of both cultivars decreased significantly with time at 40/35 °C. There was no significant difference in photosynthetic rate between the two cultivars. Nevertheless, there was difference in plant biomass between the cultivars. Raynox provided more protection against high temperature, specifically in reducing stomatal conductance and limiting transpiration, than Surround.
(432) Heat-tolerant Traits of Salvia (Salvia splendens)
Authors: Natarajan Seenivasan , Kuehny Jeff
Published: February 2019

One of the greatest impediments to the production of marketable ornamental herbaceous plants in the southern U.S. is high temperature stress. Exposure of plants to sublethal temperature (heat preconditioning) prior to sustained heat stress helps some plants to tolerate subsequent heat stress, a phenomenon often referred as acquired thermotolerance. The objective of this experiment was to examine various morphological, physiological, and anatomical responses of two red varieties of each of the `Vista' (heat tolerant) and `Sizzler' (heat sensitive) series of Salvia splendens to heat preconditioning (HC) and subsequent heat stress treatments [challenging temperatures (CT)]. Cultivars of salvia were subjected to short duration (3 hours) HC of 35 °C every third day until 5 weeks after germination and subsequent exposure to two CT treatments: 30/23 °C and 35/28 °C (day/night) cycles in growth chambers until flowering. Plant growth, marketable quality, stomatal conductance and net photosynthesis declined for `Sizzler' without HC treatment. Compared with nonpreconditioned plants, heat-preconditioned `Sizzler' had 38.28% higher root dry weight, 95% greater leaf thickness, and 50% higher marketable quality at 35/28 °C heat stress condition. Heat preconditioning helped both `Vista' and `Sizzler' to survive in both the heat stress treatments. `Vista' had greater heat-tolerant traits than `Sizzler'; these traits were enhanced with heat preconditioning treatment. The results demonstrated that heat preconditioning enhanced heat tolerance in varieties of salvia, which could be related to heat-tolerant traits, such as dense plant growth with shorter internodes, thicker stems, greater stomatal conductance, and extensive root growth that compensated for the transpiration water loss and cooling effect.
(434) Changes in Gene Expression Are Regulated by Temperature Stress in Pachysandra terminalis
Authors: Zhou Suping , Sauve Roger , Chen Tingting , Bhatti Sara , Long Debrah
Published: February 2019

Identification of low temperature–regulated gene expression in Pachysandra terminalis: Pachysandra terminalis is a cold-hardy, evergreen plant species. In order to identify molecular mechanism of cold tolerance of this plant species, seedlings with four fully expanded leaves were subjected to 4, 0, and –1 °C low temperature treatments. Low temperature–induced genes were identified from treated plants using cDNA differential display. The cDNA fragments were cloned onto PCR-trap vectors. Low temperature regulation of these genes was confirmed by reverse-northern blot. Sequence analysis has identified that these genes can be classified into three groups, stress-related, photosystem-related. Most of the genes cannot find matching sequences in the database. To further study the regulation of these genes by temperature fluctuation, the plants were treated at 4, 0, and 40 °C. Northern blot analysis showed that several clones showed increased expression after cold and heat shock. Previous cold treatment at 4 °C can negate the effect of heat shock on expression of these genes. Complete sequence of these genes is cloned from the cDNA library and their temporal regulation by environmental stresses is analyzed using real-time PCR.
(439) Influences of Low Temperature and Xylem Bubble Treatments on Deformed Leaves in `Hayward' Kiwi Trees
Authors: Kim Wol-Soo , Wu Xiu-Yu , Chung Soon-Ju
Published: February 2019

During the early spring, embolism symptoms may be observed on the leaves of kiwi trees after a severe, cold winter. The morphological character of embolism in young leaves in early spring is typically parachute shaped, at the basal part of kiwi shoots. Deformed leaves were observed at the beginning stage of development. To test the factors, we used water stress, low temperature, and xylem bubble treatments on kiwi vines during the winter season. Low temperature treatments on trees were carried out in a –15 °C chamber for 0, 12, 24, and 48 hours. For the xylem bubble treatment, the trees were injected with 3.5 MPa compressed air at –15 °C for 24 hours. For water stress treatments, the trees were not irrigated until dry soil conditions reached as little as 50% soil moisture. Treated kiwi trees planted in plastic pots (20 cm × 25 cm) were moved into the growth chamber at 25 °C with 12 hours of light, and the rate of deformed leaf symptoms was observed. In all treatments, deformed leaves were observed and bud burst rates were lower than for the control. Therefore, we confirmed that the main factors for deformed leaves were low temperature, xylem bubbles, and water stress.
(109) Evaluation of Weather-sensing Landscape Irrigation Controllers
Authors: Pittenger Dennis R. , Shaw David A. , Richie William E.
Published: February 2019

We conducted an evaluation of three commercial weather-sensing irrigation controllers to determine the climatic data they use, how easy they are to set up and operate, and how closely their irrigation regimes match landscape irrigation needs established by previous field research. The devices virtually controlled an existing reference irrigation system and used its system performance data as required in their initial setup. Reference standard treatments for cool-season turfgrass, trees/shrubs and annual flowers were calculated using onsite, real-time reference evapotranspiration (ETo) data and plant factors developed primarily from previous research. The reference irrigation system applied the correct amount of water to an actual tall fescue turfgrass planting whose water needs served as the reference standard treatment comparison for the cool-season turfgrass treatment. Virtual applied water was recorded for other plant materials and it was compared to the corresponding calculated reference standard amount. Results show each controller adjusted its irrigation schedules through the year roughly in concert with weather and ETo changes, but the magnitudes of adjustments were not consistently in proportion to changes in ETo. No product produced highly accurate irrigation schedules consistently for every landscape setting when compared to research-based reference comparison treatments. Greater complexity and technicality of required setup information did not always result in more accurate, water-conserving irrigation schedules. Use of a weather-sensing controller does not assure landscape water conservation or acceptable landscape plant performance, and it does not eliminate human interaction in landscape irrigation management.
(115) Soil Inoculum Potential and Mycorrhizal Colonization of Acer rubrum in Forested and Developed Landscapes
Authors: Wiseman P. Eric , Wells Christina
Published: February 2019

Arbuscular mycorrhizal fungi (AMF) form a symbiotic relationship with numerous landscape tree species and can improve tree growth and environmental stress tolerance. Construction-related soil disturbance is thought to diminish AMF colonization of transplanted trees in newly developed landscapes. We gathered root, soil, and foliar data from red maples (Acer rubrum) growing in newly developed landscape sites and adjacent native forest sites to test the hypotheses that: 1) landscape trees show lower levels of AMF colonization than forest trees; and 2) the AMF inoculum potential of landscape soils is lower than that of forest soils. Fine roots sampled from landscape maples had significantly lower AMF colonization than maples from adjacent forest sites (3% vs. 22%; P= 0.0002). However, soil-sand mixtures made from landscape soils possessed greater AMF inoculum potential than those made from forest soils (10% vs. 4%; P= 0.0081). Forest soils were more acidic and possessed less extractable P than landscape soils, and differences in AMF colonization between forest and landscape maples appeared to reflect differences in soil chemical properties rather than in soil inoculum potential.
(116) Short-term Responses of Live Oak to Planting Depth and Soil Amendments
Authors: Bryan Donita L. , Watson W. Todd , Lombardini Leonardo , Sloan John J. , Cartmill Andrew D. , Denny Geoffrey C. , Arnold Michael A.
Published: February 2019

Tree transplanting practices influence plant survival, establishment, and subsequent landscape value. However, transplanting practices vary substantially within the horticultural industry. Of particular importance is the location of the root collar relative to soil grade at transplant. The objective of this study was to determine the effects of factorial combinations of planting depths, root collar at grade or 7.6 cm either above or below grade, and soil amendments on container-grown (11 L) Quercus virginiana Mill. Soil treatments included a tilled native soil (heavy clay loam, Zack Series, Zack-urban land complex, fine, montmorillonitic, thermic, udic paleustalfs), native soils amended with 7.6 cm of coarse blasting sand or peat that were then tilled to a depth of 23 cm, or raised beds containing 20 cm of sandy loam soil (Silawa fine sandy loam, siliceous, thermic, ultic haplustalfs). A significant (P ≤ 0.05) block by soil amendment interaction occurred for photosynthetic activity. Incorporation of peat significantly decreased the bulk density of the native soil. Planting depth had no significant effect on photosynthetic activity or stem xylem water potential at 3 months after transplant. Soil water potentials did not statistically differ among treatments.
(117) A Profile of Landscape Service Providers in West Central Florida
Authors: Vyapari Sudeep , Graves Robert J. , Thralls Edmund L.
Published: February 2019

A survey of landscape service providers was conducted in conjunction with the 2004 Tree and Landscape Short Course in Tampa, Fla. A greater proportion of participants (56%) provided landscape maintenance services, and 60% of the businesses were independently owned. About 67% of the respondents indicated that their businesses were in operation for over 10 years with 33% of the participants making one million dollars or more in gross sales per year. Although 43% of the respondents indicated that they served only one type of account, at least 29% of the providers served two types of accounts, and 24% served three types. In response to various questions on a Likert scale of 1–5, about 39% of the respondents completely agreed that word-of-mouth is the best marketing method and 41% agreed that an attractive logo on company trucks works as a great marketing tool. Many participants either agreed (27%) or were neutral (27%) when asked if they thought that the customers have no understanding of the costs involved in providing services to them. The survey results show that 73% of the respondents believe the most important factor that impacts and helps retain a customer base at a steady level is quality of work performed followed by professional employees, appearance, and knowledgeable employees. Cheap prices or discounts offered were rated as being low factors in retention of customers. Most service providers (31%) do not communicate with their customers using brochures, newsletters, flyers, emails, or websites. About 61% of service providers promote low water use plants followed by use of Florida native plants.
(288) An Arabidopsis thaliana Phytochelatin Synthase (AtPCS1) Gene Expressed in Transgenic Indian Mustard Contributes Partial Tolerance to Cd and Zn
Authors: Gasic Ksenija , Korban Schuyler S.
Published: February 2019

Phytochelatins (PCs) are heavy metal binding peptides that play important roles in sequestration and detoxification of heavy metals in plants. To develop transgenic plants with increased tolerance and/or accumulation of heavy metals from soil, an Arabidopsis thaliana FLAG–tagged AtPCS1 cDNA encoding phytochelatin synthase (PCS) under the control of a 35S promoter was expressed in Indian mustard (Brassica juncea). Four transgenic Indian mustard lines, designated pc lines, with different levels of AtPCS1 mRNA accumulation and correspondent AtPCS1 protein levels were selected and analyzed for tolerance to cadmium (Cd) and zinc (Zn). Heavy metal tolerance was assessed by measuring root length of 10-day-old seedlings grown on agar medium supplemented with different concentrations of Cd (0, 100, 150, and 200 μm CdCl2) and Zn (200, 400, 600, and 800 μm ZnCl2). All transgenic lines showed significantly longer roots when grown on a medium supplemented with 100 μm CdCl2. No significant differences were observed between transgenic lines and wild type when plants were grown on higher levels of Cd. This indicated that only partial tolerance to Cd was observed in these transgenic lines. Similarly, partial tolerance for Zn was also observed in these transgenic lines, but up to levels of 400 μm ZnCl2. Expression levels of AtPCS1 protein were not related to tolerance responses for either Cd or Zn stresses in transgenic lines.
(291) Adventitious Shoot Production and Transformation of Euonymus alata
Authors: Smith Alan G. , Zimmermann Elizabeth S.
Published: February 2019

Euonymus alata is an attractive landscape plant that has been reported to be an invasive species. Genetic modification through transformation is a method of reducing its invasiveness by producing sterile cultivars having limited or no seed production. A critical step in Agrobacterium-mediated gene transfer is the production of adventitious shoots. E. alata internodes and leaves from in vitro cultures were tested for adventitious shoot production on 16 plant growth regulator combinations: four levels of 6-benzylamino purine (BA) and three auxin treatments [0.5 or 0.25 mg·L-1 indole-3-butyric acid and 0.1 mg·L-1 naphthaleneacetic acid (NAA)], as well as no auxin. The optimal BA levels were found to be 0.5 or 1.0 mg·L-1 for maximizing the number of explants forming shoots and for producing the greatest number of shoots per explant. Culturing on NAA gave the greatest number of shoots per explant with both 0.5 and 1.0 mg·L-1 BA. Shoot production from internode segments was markedly superior to leaves. An initial dark treatment of 10 days did not influence shoot production. Using 1.0 mg BA with 0.1 mg·L-1 NAA, E. alata internodes were transformed with A. tumefaciens EHA105 carrying Kanamycin resistance and β-glucuronidase genes. Transformed shoots were selected on 30 mg·L-1 Kanamycin. Of the 36 shoots produced, 16 were confirmed to be transformed by β-glucuronidase histochemistry. Treatment with rooting powder containing indole-3-butyric acid did not aid rooting of shoots, but after 3 months in soil in high humidity, 21 of 24 E. alata shoots from tissue culture were rooted and acclimated.
(442) Catechins and Compatibility in Calocarpum sapota (Jacq.) Merr. Homografts and Calocarpum sapota on Achras sapota (L.) Heterografts during Two Phenological Stages
Authors: Gonzalez Juan Manuel González , Dominguez Oscar Rebolledo , Jimenes Lourdes Diaz
Published: February 2019

The responsible substances involved in the phenomenon of compability/incompatibility in Sapotaceae species during two phenological stages were elucidated. An experiment was carried out to determine the compatibility/incompatibility relationship between homografts and heterografts of Sapotaceae species during two phenological stages, and to identify the responsible substances involved in the phenomenon. In order to determine the compatibility/incompatibility between Sapotaceae species, heterograftings were made using the mamey [Calocarpumsapota(Jacq.) Merr.] as scion, and chicozapote [(Achrassapota(L.)] was used as rootstock. Grafting was conducted during the phenological stage of defoliation of the scion donor plant, as well as during budding. Homografts were also made using C. sapota on C. sapota in both phenological stages. Plant tissue samples were obtained from scions and rootstocks in both phenological stages, and they were used for HPLC analysis. Heterografts (C. sapota on A. sapota) showed 100% incompatibility in both stages, and lack of success during grafting was obtained; similar results were registered with the homografts (C. sapota on C. sapota) during the budding stage; however, during the defoliation stage, 80% successful grafting was obtained. The responsible substances involved in the phenomenon of compatibility/incompatibility using samples taken during the grafting day and 60 days after (C. sapota grafted on A. sapota during defoliation stage), were identified as catechin and epicatechin. Catechins are the responsible substances of incompatibility in the heterografts of C. sapota /A. sapotain both phenological stages, as well as during the budding stage in the homografts on C. sapota.
(444) Management Practices to Improve Yield of Camellia oleifera Abel
Authors: Yu Jiangfan
Published: February 2019

Oil-tea plant (CamelliaoleiferaAbel), one of the four woody plants that produce edible oil for human consumption, is widely cultivated in Jiangxi Province (China) with production areas of 834,000 ha. Under conventional cultivation techniques, the oil yield of oil-tea plant was only 30 to 45 kg·ha-1, which significantly limited its economic impact and development. In the past 10 years, management practical techniques, such as preparing soil with organic fertilizer, weed control, thinning, pruning, alternated harvest time, improved harvest techniques, etc., had been implemented to replace traditional practices. Also, some new and promised clones were used to reforest and regenerate some areas with aged and degraded Camelliaoleiferaplantations. The results indicated that the new plantations and regenerated forests produced fruits for refining oil in their third year. The yield was significantly higher than that of the original stands in their fourth year and reached 712.5 kg·ha-1 in their sixth year. The highest yield, 750 kg·ha-1, was harvested at their eighth year after the new management practices. Oil-tea plant is not a low-yield and low-valued crop and the average yield could improve 6–7 times per hectare with selected clones and proper management. Both management practices and clone selection are key issues to the yield of oil-tea plant plantations. Best management techniques and better clones have been applied by the farmers today and the goal is to reforest or regenerate 80% of the production areas in Jiangxi Province. Future studies will focus on breeding better cultivars under these new management practices.
(337) Effect of Selenium Supply by Trunk Injection on Fruit Quality of `Niitaka' Asian Pear
Authors: Kim Wol-Soo , Jo Jung-An , Chung Soon-Ju
Published: February 2019

Many trials to supply selenium to fruit have been carried out since tests have confirmed selenium's role as a medical substance. Supplying selenium in orchards by soil and foliar application was not effective because of loss from rainfall. In order to increase selenium absorption by fruit, this study carried out tree trunk injections during the growing season. Selenium solutions in concentrations of 5, 10, 25, and 50 mg·L–1 were supplied to `Niitaka' pear (Pyruspyrifolia) trees by trunk injection (1.5 L/tree) four times at 15-day intervals from June 2004.

The treatment with 50 mg·L–1 selenium showed necrosis symptoms at leaf-margins after secondary treatment and toxicity as abnormally red fruit skin color. Fruit weight and leaf area were decreased by selenium treatments, while severe symptoms appeared with higher selenium concentrations. Hunter values `a' and `b' in fruit skin color were increased by selenium treatment in comparison to the control. The selenium treatment showed lower soluble solids by as much as 1.2%, and higher fruit firmness. Selenium concentration in pear fruit was increased by trunk injection with a 5 mg·L–1 solution. The bound selenium in pear fruit after 3 months of storage in cold room conditions was very high, but free selenium was low.
(120) Response of Ornamental Sunflower to Irrigation with Saline Wastewaters
Authors: Grieve Catherine M. , Poss James A. , Draper John H.
Published: February 2019

To explore the possibility that saline wastewaters may be used to grow high value floriculture crops, the effects of salinity were tested on Helianthus annuus (L.). Sunflower cultivars Sunbeam and Moonbright were grown in 30 greenhouse sand tanks and irrigated initially with nutrient solution. One week after planting, saline treatments were imposed with solutions differing in ion composition. Fifteen tanks were irrigated with waters typical of agricultural wastewaters present in the San Joaquin Valley (SJV) and 15 tanks were irrigated with water compositions similar to saline tailwaters found in the Imperial and Coachella valleys (ICV). Five treatments of each salinity type were used with electrical conductivities (EC) of 2.5, 5, 10, 15, and 20 dS·m–1. Length of the flowering stems was significantly reduced as salinity rose to 20 dS·m–1. Reduction was more pronounced when the plants were irrigated with the sodium-sulfate dominated waters of SJV composition. Flower diameter was reduced when the EC of SJV waters exceeded 15 dS·m–1, but was not affected by any treatment when ICV waters were used. Salt tolerance in sunflower appears to be associated with mechanism(s) that regulate transport of potentially injurious ions. Both Na+and Cl- were partitioned to the lowest portion of the stem, and effectively excluded from the remainder of the shoot. This study illustrates that saline waters with EC = 15 or 20 dS·m–1 may be used to produce ornamental sunflowers without significant loss of quality. Salt stress also provides an environmentally friendly alternative to the use of growth regulators for the control of plant height.
(121) Matthiola incanaas a Model Crop for Recycling Greenhouse Effluents
Authors: Poss James A. , Carter Christy T. , Grieve Catherine M. , Shouse Peter J.
Published: February 2019

Common stock flower production can be achieved under moderate levels of salinity and relatively low levels of nitrogen with no significant decrease in quality in a closed-recirculating irrigation system. A 4 × 4 factorial design with partial replication was used to assess the effects of salinity and nitrogen on the production of Matthiolaincana (L.). Seeds were sown in outdoor volumetric lysimeters at the George E. Brown, Jr., Salinity Laboratory in Riverside, Calif., with target electrical conductivity (EC) levels of 2, 5, 8, and 11 dS·m–1 combined with four nitrogen treatments of 35, 50, 75, and 100 ppm N. An empirical model was implemented to evaluate the growth response of each combination of salinity and nitrogen treatments over the course of plant development. The three-phase model is represented by an initial size parameter (alpha), an estimation of the intrinsic growth rate of the exponential phase (beta), a transitional phase between the first two phases (tl), the length of the linear phase (epsilon), and the final intrinsic saturation rate (gamma), The model successfully fitted the plant height data over time for all 16 nitrogen and salinity treatment combinations. Effects of salinity on epsilon and t2 (epsilon + t1) were nonsignificant. Nitrogen treatments had no significant effect on any of the model parameters and the effect of salinity was greatest when irrigation water EC was 11 dS·m–1. The length of the flower-bearing stems exceeded the standards recommended for commercial acceptability in all treatments (>41 cm). If 60 cm is the minimum length acceptable, then 50 ppm N or more where the EC was 8 dS·m–1 or less is required. Nitrogen uptake per unit evapotranspiration increased with salinity and nitrogen.
(127) Effects of Substrate on Nutrient Uptake and Nitrate Leaching in Lilies
Authors: Merhaut Donald J. , Newman Julie P.
Published: February 2019

Lilies are produced throughout the year in coastal areas of California.

Cultural practices involve daily applications of water and fertilizer, using both controlled release fertilizers (CRF) and liquid fertilizers (LF). However, many production facilities are in proximity to coastal wetlands and are therefore at greater risk of causing nitrogen pollution via runoff and leaching. Due to federal and state regulations, nurseries must present a plan of best management practices (BMPs) to mitigate nutrient runoff and leaching and begin implementing these practices in the next 2 years. In the following studies, we determined the potential for nitrate leaching from four different types of substrates (coir, coir: peat, peat, and native soil). There were four replications of each treatment, with a replication consisting of one crate planted with 25 bulbs. Two cultivars were used in two separate experiments, `Star Fighter' and `Casa Blanca'. Nitrate leaching was determined by placing an ion-exchange resin bag under each crate at the beginning of the study. After plant harvest (14–16 weeks), resin bags were collected and analyzed for nitrate content. Plant tissues were dried and ground and analyzed for nitrogen content. Based on the results of these studies, it appears that the use of coir, peat, and soil may not influence plant growth significantly. Substrate type may mitigate the amount of nitrate leaching through the media. However, the cultivar type may also influence the degree of nitrate mitigation, since leaching results varied between the two cultivars.
(129) Effect of Foliar Application of Calcium, Boron, and Molybdenum in Nutrient Content of Poinsettia Plants
Authors: Ayala Juan , Castillo Ana-Maria , Colinas Maria-Teresa , Pineda Joel
Published: February 2019

The effect of foliar application of calcium, boron, and molybdenum on macronutrient and micronutrient content of poinsettia (Euphorbia pulcherrima) plants cv. Supjibi was evaluated. Plants were grown under greenhouse conditions in 7-inch containers. Fourteen treatments were applied (10 replicates per treatment); these were formed by three calcium levels (calcium nitrate at 300, 400, and 500 mg·L-1),

boron (borax at 0.2, 0.5, and 0.8 mg·L-1), and molybdenum (sodium molybdate at 0.3, 0.4, and 0.5 mg·L-1) and their combinations. Plants were spayed three times during the growing period: 51, 72, and 94 days after transplant. Plants were covered with black polyethylene from 5 pm to 7 am every day in order to induce bract development.

N, P, K, Ca, Mg, B, Mo, Mn, Fe, Zn, and Cu content was evaluated 2 weeks after finishing the induction period. The treatment with a combination of Ca+Mo increased by 26% the N content compared with the control. Application of B+Mo, and Ca+B decreased the P content by 32% and 28%, respectively. Treatment with Ca+B+Mo increased foliar K by 46%. B+Mo increased 72.5% Ca content, 38% Mg, and there was about 75 times more Cu than in the control (2.20 vs. 166.7 mg·L-1). Treatments with Ca and B decreased Mn content by 32.7%. Ca (500 mg·L-1) decreased B content by 76%. Treatments did not have any significance on Mo, Fe, and Zn content. As a general conclusion it can be said that foliar applications of Ca, B, Mo, alone or in certain combinations, affected significantly the content of foliar nutrients due to specific nutrient interactions in plants.
(47) Optimal Low Pressure Conditions for Long-term Storage of Fresh Commodities Kill Caribbean Fruit Fly Eggs and Larvae
Authors: Davenport Thomas L. , Burg Stanley P. , White Thomas L.
Published: February 2019

U.S. regulations prevent importation of fresh horticultural commodities that have not received an approved quarantine treatment assuring 100% mortality of potentially invasive insect pests. Because imported mangoes are likely to be infested by the Caribbean fruit fly (Anastrepha suspensa Loew) and other tropical fruit flies such as A. ludens Loew, A. striata, A. distincta, A. fraterculus, A. serpentina, or A. oblique, they must be hot-water treated prior to shipment in order to satisfy quarantine requirement. Hot water treatment often damages the fruit, especially if it is not fully mature. Hypobaric (low pressure = LP) intermodal shipping containers developed by the VacuFreshSM Corp. preserve fresh commodities, such as horticulturally mature mangoes, far longer than is possible using other technologies. We tested the ability of over 70,000 Caribbean fruit fly eggs and larvae to survive a simulated optimal hypobaric condition for shipment of mangoes (15 mm Hg, 98% RH, at the lowest, safe non-chilling temperature, 13 °C). A. suspensa eggs or larvae were maintained on agar media, flushed with one air change per hour at the storage pressure, and shielded with Mylar to prevent radiant heat uptake and limit evaporative cooling. Nearly 98% of the eggs and larvae were killed within 1 week at 15 mm Hg in eight replicated experiments. All eggs were killed at that pressure by 11 days, whereas a significant number survived at ambient pressure. Shipment of fresh produce using this technology promises to provide quarantine control while preserving the freshness of fully mature tropical fruits and vegetables.
(48) Prestorage Delay Effects on Soft Scald and Soggy Breakdown of `Honeycrisp' Apples
Authors: Moran Renae E.
Published: February 2019

In 2004, prestorage delays and CA storage were compared for occurrence of disorders. Fruit were harvested at a starch index of 5.9. Fruit were exposed to either a 2- or 5-day prestorage delay at 17 °C; or placed immediately into cold storage (control) at 0.5 °C. An additional treatment was CA storage at 2.5 °C. In February, occurrence of soft scald, soggy breakdown, and bitter pit were measured on 40 fruit per replication. Fruit were from `Honeycrisp'/M.26 trees planted in 1994. Treatments were replicated five times with four trees in each replication. Soft scald was very severe in this year, with 84% of control fruit being affected. Two-day prestorage delay reduced it to 48% and 5-day delay to 21%. Soggy breakdown was also severe with 14% of the fruit being affected. Two- and 5-day delays had no effect on occurrence of soggy breakdown, but CA storage increased it to 65%. Bitter pit was very rare and not affected by any of the treatments. These results demonstrate that in severe cases, shorter prestorage delay is not effective in preventing soft scald or soggy breakdown.
(49) Effect of Low Temperature Storage on Quality and Enzymatic Activity of Zapote Mamey Fruit (Pouteria sapota)
Authors: Alia-Tejacal Iran , Colinas-Leon Maria-Teresa , Martinez-Damian Maria-Teresa , Soto-Hernández Marcos
Published: February 2019

Zapote mamey is a climacteric fruit that shows an increase in the content of carotenoids and total soluble sugars and in the activity of different enzymes during maturation. In the present study, zapote mamey fruits were harvested at physiological maturity and stored for 7, 14, and 21 days at 5, 10, and 15 °C, 85% relative humidity (RH). At the same time, immediately after harvest a group of fruits (control) was kept and evaluated at ambient temperature (20 °C, 50% to 60% RH). The objective was to determine the effects of temperature and storage time on content of carotenoids, and total soluble sugars, as well as to evaluate the enzymatic activity of peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD). Fruits stored at 5 °C for 14 and 21 days developed chilling injury, as shown by a negative effect on carotenoids and total soluble sugars content. The activities of POD, CAT and SOD were also reduced after storage at 5 °C for 21 days. Fruits stored at 10 and 15 °C for 7, 14, and 21 days showed similar characteristics to the control fruits in carotenoids and total soluble sugars. Enzymatic activities were affected only by storage at 10 °C for 21 days. Storage at 15 °C for 21 days delayed, but did not stop maturation. Results suggest that zapote mamey fruits can be stored at 10 °C with no negative effect on quality.
(257) Pepino Mosaic Virus: Variability in U.S. Isolates
Authors: Maroon-Lango Clarissa J. , Guaragna Mary Ann , Jordan Ramon , Hammond John , Bandla Murali , Marquardt Steve , Stommel John R.
Published: February 2019

Pepino mosaic virus (PepMV) was first found in pepino (Solanum muricatum) growing in coastal Peru in 1974 and described in 1980; it reappeared in protected tomato (Lycopersiconesculentum) in the Netherlands in 1999. Since then, it has been reported to occur in tomato in several countries including Austria, Belgium, Canada, France, Germany, Italy, Peru, Spain and the Canary Islands, the United Kingdom, and in 11 states within the United States. Three strains of PepMV found in the United States have been cloned and sequenced. Full-length genomic sequences were obtained for two strains, PepMV-US1 and PepMV-US2, from co-infected tomato plant samples from Arizona. The 3'-end sequence of PepMV-US3 came from infected tomato fruits from Maryland. The genome organization, motifs and domains typical of the genus Potexvirus, and of other PepMV isolates, were found in full-length sequences of both US1 and US2 isolates. Direct comparison of US1 and US2 at the nucleotide level revealed an 86.3% identity; whereas, when individually compared to the French and Spanish isolates, which share ∼99% identity at the nucleotide level, US1 and US2 had 82% and 79% identities to each, respectively. Pair-wise gene-for-gene comparisons between United States and European isolates revealed a similar trend. While unique, US1 is more closely related to the previously reported European isolates than is US2. The CP of US3 is nearly identical to the European isolates at the amino acid level. None of 18 tomato germplasm accessions or 10 cultivars were resistant to mechanical inoculation with US3; in contrast, no infection was detected in nine pepper cultivars or four germplasm accessions. Plants grown from seeds of infected tomato fruits did not test positive for PepMV.
(259) A Genetic Linkage Map and a cDNA Library for Watermelon
Authors: Levi Amnon , Thomas C.E. , Davis Angela , Reddy O.U.K. , Xu Y. , Zhang X. , Hernandez A. , Gusmini G. , Wehner Todd C. , King J. , King S.R.
Published: February 2019

A genetic linkage map was constructed for watermelon based on a testcross population and an F2 population. The testcross map includes 312 markers (RAPD, ISSR, AFLP, SSR, and ASRP). This map covered a genetic distance of 1385 cM, and identified 11 large (50.7-155.2 cm), five intermediate (37.5-46.2 cm), and 16 small linkage groups (4.2-31.4 cm). Most AFLP markers are clustered in two linkage regions, while all other markers are randomly dispersed throughout the genome. Many of the markers in this study were skewed from the classical (Mendelian) segregation ratio of 1:1 in the testcross or 3:1 in the F2 population. The order of the markers within linkage groups was similar in the testcross and F2 populations. Additionally, a cDNA library was constructed using RNA isolated from watermelon flesh 1 week (rapid cell division stage), 2 weeks (cell growth and storage deposition stage), 4 weeks (maturation stage), and 5 weeks (mature fruit) after pollination. More than 1020 cDNA clones were sequenced, and analyzed using the basic local alignment search Tool (BLAST). The sequenced cDNA clones were designated as expressed sequenced tag (EST). The ESTs were searched for simple sequence repeats. About 7% of the ESTs contained SSR motifs. The ESTs containing SSRs are being used to design PCR primers and the putative markers are being tested for polymorphism among the parental lines of the mapping populations. Polymorphic markers will then be mapped using the mapping populations.
(260) Development of SCAR and CAPS Markers Linked to Tomato Begomovirus Resistance Genes Introgressed from Lycopersicon chilense
Authors: Ji Yuanfu , Scott John W.
Published: February 2019

Resistance to begomoviruses tomato mottle virus (ToMoV) and tomato yellow leaf curl virus (TYLCV) has been introgressed to tomato (Lycopersicon esculentum) from L. chilense accessions LA 1932, LA 2779, and LA 1938. Resistance genes have been mapped to three regions on chromosome 6 using randomly amplified polymorphic DNA (RAPD) markers. We call these regions 1, 2, and 3. To facilitate breeding by marker assisted selection, advanced breeding lines with resistance from the above sources were assayed for the presence of RAPD markers to determine which were most tightly linked to begomovirus resistance. The best RAPD markers were then converted to sequence characterized amplified region (SCAR) markers or cleaved amplified polymorphic sequence (CAPS) markers. In addition, selected restriction fragment length polymorphism (RFLP) markers near the three regions were converted into CAPS markers, which were tested for association with the advanced breeding lines. Only LA 2779 derivatives have the L. chilense introgression in region 1, which is near the location of the Ty-1 gene and spans across CAPS markers 32.5Cla and TG118. Two region 1 RAPD markers UBC197 and UBC621 were converted co-dominant SCAR or CAPS markers, which were present in all 16 resistant breeding lines tested. Derivatives from all three accessions have introgressions in region 2. Further assays with more markers in this region are under way to determine the lengths and locations of the introgressions. No tightly linked RAPD markers have been found for the resistance gene from LA 1932 in region 3. RFLP and CAPS markers are being used to more precisely locate the region 3 gene.
(470) Lycopene Content of Mini Watermelon Varieties Grown at Four Locations
Authors: Perkins-Veazie Penelope , Collins Julie , Hassell Richard , Olson Steve , Maynard Donald , Schultheis Jonathan , O'Hern Missy , Magby Toni , Magby Shelli
Published: February 2019

Mini watermelons are the size of cantaloupes and weigh 1.5 to 3 kg (4 to 8 lbs). Melons of 18 selections were grown in replicated trials in North Carolina, South Carolina, and north and south Florida. Melons were harvested when ripe, and samples of heart and locule tissue were frozen and sent to Lane, Okla. A total of 960 samples, representing 6-12 melons per selection per location, were analyzed for total lycopene content using colorimeter and spectrophotometer methods. Subsamples of `Mohican', `Hazera 6007', `Vanessa', `Petite Treat', and `Precious Petite' were analyzed by HPLC for carotenoid profiles. Total lycopene content ranged from 52 to 108 μg·g-1, depending on variety. Selections were grouped into two levels of lycopene content. The varieties Precious Petite, Petite Perfection, Betsy, Bonny, Petite Treat, Valdoria, Vanessa, Hazera 5133 and 5138, RWT 8149, 8155, 8162 had 60 to 79 μg·g-1 lycopene and the varieties Hazera 6007, 5123, 5109, 5177, Mohican, and Extazy had 80 to 100 μg·g-1. Melons harvested from the Florida locations had more total lycopene than those from North and South Carolina. `Precious Petite' had more β-carotene as a percentage of total carotenoids than other varieties tested. These results indicate that lycopene content is affected primarily by germplasm and also by environment.