bluuebunny/crossref_metadata_2025 huggingface dataset:
IMPACT OF NUTRIENT REPLENISHMENT ON HYDROPONIC SWEETPOTATO CULTURE
Authors: Trotman Audrey A. , David P. , Mortley D. , Seminara J.
Published: February 2019

In a greenhouse experiment, the effect of the addition of higher levels of potassium (K) in the replenishment stock used to supply nutrients in a nutrient film technique system was examined. For this study, `TU-82-155' sweetpotato was grown hydroponically for 120 days under four nutrient application/replenishment treatments: 1) REG—solution was changed at 14-day intervals and volume allowed to fluctuate; 2) MHH—replenishment with 10× concentrate of a modified half Hoagland solution (MHH) or with water to regain set volume (30.4 liters) and maintain set point of electrical conductivity (EC, 1050–1500 μmho); 3) MHH + 2K—daily replenishment with 10× concentrate of a modified half Hoagland solution (MHH) or with water to regain the set volume and adjust EC to 1400 followed by application of 50 ml of a 2K stock solution to an EC of 1500; 4) MHH/2K—replenishment with 10× concentrate of a modified half Hoagland solution that incorporated the 2K component or with water to regain set volume (30.4 liters) and maintain set point of electrical conductivity (EC, 105–1500 μmho). The storage root yield (g fresh weight per plant) was significantly higher when the 2K treatment was incorporated with the 10× MHH stock. The storage root yield averaged 324.8 g/plant compared with a yield of 289.6 and 252.9 g/plant, respectively, for the REG and MHH nutrient application protocol. As in earlier experiments, the MHH treatment was comparable to the REG protocol, validating the use of a replenishment approach for nutrient supply in hydroponic sweetpotato culture.
DEVELOPMENT OF SOUTHERNPEA CULTIVARS WITH GREEN COTYLEDON PHENOTYPES
Authors: Fery Richard L.
Published: February 2019

A breeding program was initiated in 1990 to develop cream-, blackeye-, and pinkeye-type southernpea [Vigna unguiculata (L.)] cultivars homozygous for the gc gene conditioning green cotyledons. The green cotyledon trait allows harvest at the near-dry seed stage of maturity without loss of the seed's fresh green color. The ability to select for the gc gene in the embryo stage greatly facilitated its use in breeding programs, and the development of advanced breeding lines has proceeded at an accelerated rate. Sixteen F9 and 15 F10 breedinglines homozygous at the gc locus were available for preliminary field testing in 1995. The results of this field testing indicate that the efforts to incorporate the gc gene into elite horticultural germplasm have been successful. More importantly, the results of tests conducted with seed harvested at the dry stage of maturity indicate that several of the lines should produce an excellent processed product.
CONTRIBUTION OF HOST PLANT RESISTANCE TO CONTROL OF COWPEA CURCULIO IN SOUTHERNPEAS
Authors: Hunter A.G. , Chambliss O.L. , Wells L.O.
Published: February 2019

Nine southernpeas, varying in their resistance to cowpea curculio, and the susceptible California Blackeye # 5 (CBE) were tested with six treatments: methyl parathion and endosulfan at recommended and one-quarter rate, a control with tractor traffic, and one without traffic. CBE had 42.7% curculio-damaged seeds over all treatment, while resistant entries ranged from 3.7% to 9.5%. Over all entries, methyl parathion at the recommended rate resulted in the lowest percentage of curculio-damaged seed (7.3%); endosulfan at the recommended rate was next with 9.1%. The percentage of damaged seed was not significantly different for the methyl parathion and endosulfan treatments using one-quarter recommended rates, the control with traffic, and the control without traffic—10.8%, 11.2%, 12.6%, and 11.7%, respectively. `Carolina Cream' (3.7% damaged seed over all treatments) and methyl parathion at the recommended rate resulted in the lowest percentage of curculio damaged seed: 1.3%.
Organic Mulch and Nitrogen Affect Spring and Fall Collard Yields
Authors: Guertal E.A. , Edwards J.H.
Published: February 2019

Fall and spring collards (Brassica oleracea L. Acephala Group) were grown under one of three mulches (black plastic, ground newspaper, wood chips) and in a bare soil control. Mulch treatments were arranged in a factorial design with five rates of N fertilizer: 0, 67, 134, 201, or 268 kg N/ha. All fertilizer was preplant-incorporated into the bed before applying mulches and transplanting collards. Season did not affect collard yield, and there was no significant season × N rate interaction. Collard yields increased with increasing rates of N, with a maximum yield at 163 kg N/ha. Mulch type significantly affected collard yield, with fall collard yields highest under bare ground or wood chip mulches and spring yields highest under black plastic mulch. Collards produced under newspaper mulch produced the lowest yields in the fall and yields equal to bare soil and wood chips in the spring. Collards produced under newspaper mulch had less tissue N at harvest than those of any of the other treatments in both seasons. Collards produced on black plastic produced the lowest plant populations in both seasons. Wood chips and newspaper offer some appeal as low-input, small-scale mulches, but additional research to explore fertility management is necessary.
Seed Production on Detached Culms of Pearl Millet × Elephantgrass Hexaploid Hybrids
Authors: Schank S.C. , Diz D.A. , Wofford D.S.
Published: February 2019

Five nutrient solutions were evaluated in the greenhouse to determine which solutions would allow detached culms of Pennisetum to produce seed. The genotypes tested originated from the hybridization of Pennisetum glaucum L. (Pearl millet) × P. pennisetum Schum. (elephantgrass). The solutions were water, Hoagland's, sucrose, sucrose + hydroxyquinoline sulfate (HQ), and Hoagland's + sucrose + HQ. Neither the water nor the Hoagland's solution supported high seed set. Although the sucrose solution enhanced seed production, the seeds were low in weight and did not germinate well. The best nutrient solutions were 2% sucrose + 0.02% HQ or Hoagland's + 2% sucrose + 0.02% HQ. The four genotypes used differed substantially in seed production, but all produced seed, with germination >25%. This result indicates that the cut-culm technique is a possible way of getting recurrent restricted phenotypic selection seed in Pennisetum hexaploid hybrids.
Postharvest Quality of `Thompson Seedless' Grapes after Insecticidal Controlled-atmosphere Treatments
Authors: Ahumada Miguel H. , Mitcham Elizabeth J. , Moore Denise G.
Published: February 2019

Non-SO2-fumigated `Thompson Seedless' table grapes (Vitis vinifera L.) were stored at 5 or 20 °C for 6 and 4.5 days, respectively, in air or one of four insecticidal controlled atmospheres (ICA); 0.5% O2 + 35% CO2; 0.5% O2 + 45% CO2; 0.5% O2 + 55% CO2; or 100% CO2. The fruit were evaluated for weight loss, berry firmness, soluble solids concentration (SSC), titratable acidity, berry shattering, rachis browning, berry browning, and volatiles (acetaldehyde and ethanol). Fruit quality was not affected at 5 °C with the exception of greater rachis browning in fruit treated with 0.5% O2 + 45% CO2. At 20 °C, ICA treatments maintained greener rachis compared to the air control; however, SSC was reduced in the fruit treated with 55% and 100% CO2. At both temperatures, ICA induced the production of high levels of acetaldehyde and ethanol. Ethanol concentrations were two-thirds lower at 5 °C than at 20 °C. Consumer preference was negatively affected by some ICA treatments for grapes kept at 20 °C, but not by any of the treatments at 5 °C. Preliminary data for mortality of omnivorous leafroller pupae (Platynota stultana Walshingham), western flower thrips (Frankliniella occidentalis Pergande) adults and larvae, and pacific spider mite (Tetranychus pacificus McGregor) adults and larvae indicate that many of the ICA treatments would provide significant insect control.
Gibberellin Levels Are Not a Suitable Indicator for Properly Cold-treated Tulip Bulbs
Authors: Rebers Mariken , Vermeer Evert , Knegt Erik , van der Plas Linus H.W.
Published: February 2019

To find a suitable indicator for properly cold-treated tulip bulbs (Tulipa gesneriana L. cv. Apeldoorn), the content of the endogenous free gibberellins (GAs) GA1, GA4, GA9, GA24, and GA34 was investigated. GA levels were measured in the shoots and basal plates at the start and at the end of a complete cold treatment of 12 weeks at 5 °C by combined gas chromatography–mass spectrometry using deuterated internal standards. Bulbs stored at 17 °C for 12 weeks served as controls and the experiment was repeated three times. Before the cold treatment, GA1 and GA4 were the major occurring GAs in the shoots. After 12 weeks, GA4 was the main GA component and the levels of GA1 were low in precooled and nonprecooled bulb shoots. The levels of GA4, GA9, GA24, and GA34 in precooled and nonprecooled bulb shoots and basal plates were similar. Hence, no direct correlation between cold-stimulated growth and a change in the endogenous GA status in shoots or basal plates was determined during the cold treatment. The free GA content in shoots or basal plates at the end of bulb storage cannot be used as a marker in a test for properly cold-treated `Apeldoorn' tulip bulbs.
Irradiance Level and Fertilizer Rate Affect Acclimatization of Chamaedorea elegans Mart.
Authors: Reyes Trinidad , Nell Terril A. , Barrett James E. , Conover Charles A.
Published: February 2019

The effect of irradiance and fertilizer level on the acclimatization of Chamaedorea elegans Mart. was studied. Chamaedorea elegans was grown for 4 months in 1.6-liter pots under 162, 306, or 564 μmol·m–2·s–1 and fertilized weekly with 20N–4.7P–16.6K soluble fertilizer at 220, 440, or 880 mg/pot. At the end of the production period, plants were moved to interior rooms and maintained for 2 months at 20 μmol·m–2·s–1 for 12 h daily at 21 ± 1C and a relative humidity of 50% ± 5%. At the end of the production phase, the light compensation point (LCP) and the concentration of nonstructural carbohydrates were lower, and chlorophyll concentration was higher the lower the irradiance level. Increasing fertilizer concentration decreased the number of fronds, LCP, and nonstructural carbohydrates. After 2 months in the interior environment, LCP and number of fronds of C. elegans did not differ among treatments. Chlorophyll concentration of plants grown under 564 μmol·m–2·s–1 had increased 61%, while starch in the stem had decreased 43% relative to the concentration found at the end of the production period. In C. elegans grown under 306 μmol·m–2·s–1, stem starch depletion was only 13% during the interior evaluation period. These results indicated that C. elegans grown under the highest irradiance level used reserved carbohydrates in the interior environment while adjusting to low light and producing new leaves. Chamaedorea elegans was best acclimatized at the intermediate irradiance and medium fertilizer concentration.
Horticultural and Potential Breeding Value of Sugar Pea Landraces from Northwestern Spain
Authors: Amurrio J.M. , de Ron A.M. , Santalla M.
Published: February 2019

Twenty sugar pea (Pisum sativum L.) landraces common to northwestern Spain (Pontevedra), and potentially of interest as parental material, were evaluated at two locations and for 2 years to study the diversity among them for plant and pod physical quality traits. The main objective was to identify landraces that could be included in breeding programs. Highly significant differences among landraces were found for most of the pod traits, such as length, width, length/width index, fresh weight, and flowering date. Genotype–environment interactions were demonstrated for only three traits of the 10 investigated. High values for correlation coefficients were mostly found for pod traits, but highly significant ones (i.e., P ≤ 0.01) were found for traits other than for pods. Most of the landraces were variable for qualitative and quantitative traits. PSM-0070, PSM-0113, and PSM-0116 were superior for earliness and pod physical quality, but were heterogenous. PSM-0064, PSM-0066, PSM-0117, and PSM-0118 lacked pod parchment.
A New Procedure to Prepare Slides of Metaphase Chromosomes of Roses
Authors: Ma Yan , Islam-Faridi M. Nurul , Crane Charles F. , Stelly David M. , Price H. James , Byrne David H.
Published: February 2019

To our knowledge, there has been no published technique to produce consistently high-quality slides of somatic chromosomes of roses (Rosa sp.). Therefore, various pretreatments, fixatives, digestions, stains, and maceration and squashing methods were tested to identify a procedure to produce clear, well-spread chromosomes from shoot tips. The best results were obtained after pretreatment in a mixture of 0.1% colchicine and 0.001 m 8-hydroxyquinoline for 4 h, and fixation in 2 acetone: 1 acetic acid (v/v) with 2% (w/v) polyvinylpyrrolidone. The darkest-stained chromosomes were obtained with carbol-fuchsin staining of air-dried cell suspensions that had been spread in 3 ethanol: 1 acetic acid (v/v).
Raw Paper Mill Sludge in A Rooting Medium for Deciduous Woody Cuttings
Authors: Chong Calvin , Hamersma Bob
Published: February 2019

Stem cuttings of seven deciduous landscape shrubs {silky dogwood (Cornus amomum Mill.), coralberry (Symphoricarpos orbiculatus Moench), Peegee hydrangea (Hydrangea paniculata Siebold. `Grandiflora'), Bridal-wreath spirea [Spiraea ×vanhoutteii (C. Briot) Zab.], spirea (Spiraea ×bumalda Burv. `Goldmound'), fragrant viburnum (Viburnum farreri Stearn), and weigela [Weigela florida (Bunge) A. DC. `Variegata Nana']} were rooted under mist in 100% perlite (no sludge) medium or in mixtures of 10%, 20%, 30%, 40%, 50%, or 60% (v/v) of raw paper mill sludge and perlite. There was a large linear reduction in percent rooting of viburnum (from 80% to 21% with 0% and 60% sludge, respectively) in response to increasing level of sludge. The mean root count per cutting also was significantly decreased, from 14 to 5. However, the length of longest root was unaffected. In contrast, all the other species ranked good to excellent in rooting, regardless of the level of sludge. Differences, if any, in rooting performance were not of practical significance.
Genetic Influence on Flower Bud Density in Peach and Nectarine Exceeds That of Environment
Authors: Okie W.R. , Werner D.J.
Published: February 2019

Spring frosts often kill all or a portion of the flowers on peach [Prunus persica (L.) Batsch] trees in the southeastern United States. Increased flower bud density increases the likelihood of sufficient flowers surviving to produce a crop. The effect of environment on flower bud density (buds/node) was studied using two locations over 3 years. Bud density of 25 peach and nectarine varieties grown in completely randomized designs was measured in Georgia and North Carolina. Genotypic variability was greater than location or year effects. Varieties selected for high bud density at one location can be expected to have high densities at other locations with similar chilling.
Comparison of Capsicum annuum and C. pubescens for Antixenosis as a Means of Aphid Resistance
Authors: Bosland Paul W. , Ellington John J.
Published: February 2019

Accessions of Capsicum annuum L., a susceptible host, and C. pubescens (R. & P.), a resistant host, were grown in a replicated greenhouse study to test whether antixenosis (nonpreference), antibiosis, or both was the mechanism for resistance to green peach aphid [Myzus persicae (Sulzer)]. A plant choice experiment established that aphids preferred C. annuum to C. pubescens. A no-plant choice test was not undertaken; nevertheless, the aphid's reproductive rates were measured in leaf containment cages and were similar on both hosts. The mechanism of antibiosis was not indicated because fecundity was not reduced in the containment cages; however, other measures of antibiosis were not studied. These observations suggest that antixenosis may be functioning in C. pubescens.
Adventitious Root Formation and Development in Cuttings of Mussaenda erythrophylla L. Schum. & Thonn.
Authors: St. Hilaire Rolston , Berwart Carlos A. Fierro , Pérez-Muñoz Carlos A.
Published: February 2019

Mussaendas (Mussaenda spp.) are ornamental shrubs, and some cultivars are difficult to root. This study was conducted to explore how adventitious roots initiate and develop in the cultivar Rosea and to determine if anatomical events are associated with difficulty in rooting stem cuttings. Stem cuttings were treated with 5, 10, 15 mmol IBA, or distilled water, and sampled every 2 days over 26 days to observe adventitious root formation and development. Adventitious roots initiated from phloem parenchyma cells. Cuttings treated with 15 mmol IBA had a mean of 18 root primordia per basal 1 cm of cutting after 10 days. Primordia were absent in nontreated cuttings at 10 days. These results suggest that nontreated cuttings are difficult to root because few primordia are produced. Chemical name used: 1H-indole-3-butyric acid (IBA).
FINE FESCUE SPECIES AND CULTIVARS FOR GOLF COURSE ROUGH AND MOUND USE
Authors: Pennucci Annamarie
Published: February 2019

Five species and 27 cultivars of fine-leaved fescues (Festuca sp.) were evaluated for low-maintenance utility turf in a variety of golf course conditions. Cultivar selection and management techniques varied across six sites in 4 years. Germination, tillering, rapidity of establishment, turf density, and general turfgrass quality were significantly different between both species and cultivars. Annual and seasonal decline and recovery of turf quality was also dependent on both species and cultivar. Greater differences exist within cultivars in some species than between species. Aspect, slope, soil disturbance, shade, seeding date, irrigation, fertility regime, mulch, and mowing influenced establishment and seedling development. Absence of endophytic fungi and development of diseases, insects, weeds, and post-germination disturbance markedly contributed to losses in turf quality, percent living cover, and increased erosion potential. Success and duration of fescue slope plantings are both positively and negatively correlated to various site characteristics and management techniques. Fescues are an appropriate choice in specific circumstances.
BIOCHEMICAL AND HEREDITARY STUDIES ON ENZYMES AND GENES CONTROLLING ANTHOCYANIN SYNTHESIS IN APPLES
Authors: Ju Zhiguo , Liu Chenglian , Yuan Yongbing , Wang Yongzhang , Liu Gongshi
Published: February 2019

Crosses between red cultivars produced high frequency of less-colored progeny, while hybridization between non-red cultivars yielded some red-fruited F1 trees. When harvest was delayed and light intensity increased, both green and yellow cultivars accumulated some anthocyanin with higher UDPGal:flavonoid-3-o-glycosyltransferase (UFGalT) activity in colored areas. Overall, anthocyanin accumulation and UFGalT activity were highly correlated (r = 0.8921, P = 0.0001) in fruit from both parental trees and their F1 progeny, but UFGalT activity always was relatively high in fruit peel, whether anthocyanin accumulated or not. There were no significant differences in phenylalanine ammonia-lyase or chalcone synthase activities among the cultivars, and they did not change much after hybridization.
ENHANCEMENT OF POSTPRODUCTION QUALITY OF EASTER LILY BY GROWTH REGULATORS
Authors: Han Susan S.
Published: February 2019

The development of postproduction foliar chlorosis is one of the critical problems that remains unsolved in Easter lily production. Plants at the white puffy stage were sprayed with 500 mg gibberellic acid (GA3)/liter, 500 mg benzyladenine (BA)/liter, 500 mg each GA3 and BA/liter, 500 mg ProGibb (containing 500 mg GA3/liter)/liter, and 1000 mg Promalin (containing 500 mg GA4 + GA7/liter and 500 mg BA/liter)/liter, and a water control. Development of foliar chlorosis was evaluated in a simulated interior environment at a temperature of 22.6 ± 0.2C and illuminated 12 h·d–1 with 11.2 ± 0.1 mmol·m–2·s–1 from cool-white fluorescent lamps. Results demonstrated that GA3, BA, ProGibb, and Promalin are effective in delaying the development of foliar chlorosis of cold-stored plants. Promalin was the most effective. Concentrations of Promalin as low as 50 mg· liter–1 were effective. Treatments had no effect on the development and the longevity of flower buds. This study thus suggests that application of Promalin to Easter lily plants prior to marketing is a viable solution to preventing postproduction development of foliar chlorosis.
ORGANELLE-SPECIFIC LOCALIZATION OF IPTASE IN TRANSGENIC NICOTIANA
Authors: Rogers Gregory S. , Frett John J.
Published: February 2019

Nicotiana transformed with the isopentenyl transferase (ipt) gene from Agrobacterium tumefaciens was fixed for 1 h in 1% glutaraldehyde and 4% formaldehyde. Ultrathin sections were collected on nickel grids. Grids were treated with polyclonal anti-IPTase antibody raised in rabbits and visualized with 10 nm, protein-A–labeled colloidal gold. Gold label was found throughout the cell, including the cell wall, vacuole, rough ER, and organelles. Cell wall and vacuole labeling appears to be due to non-specific binding and is greatly reduced by a BSA block. Mitochondria and chloroplasts also showed gold label, but not greater than established background levels. Labeling above background levels on the rough ER, free polysomes, and further label in the free cytoplasm indicate a cytoplasmic role for IPTase.
SEED QUALITY EFFECTS ON HYDROPONIC LETTUCE
Authors: Korkmaz Ahmet , Pill Wallace
Published: February 2019

Achievement of head size uniformity at final harvest reduces loss and increases profitability for the hydroponic lettuce grower. Shoot fresh weight of `Cortina' lettuce (Lactuca sativa L.) at 7 or 21 days after planting (DAP) was inversely proportional to the number of days required for seedling emergence, and was greater for raw than for pelleted seeds. Head fresh weight at final harvest (61 DAP) was directly proportional to seedling length at 21 DAP, but raw and pelleted seeds produced equal head weights. Thus, initial seed (seedling) vigor differences were maintained to final harvest. Osmotic seed priming (–1.5 MPa KH2PO4, 20 h, dark) led to increased germination rate at 15, 25, and 35C; had no effect on germination synchrony; and increased germination percentage only at 35C. Covering raw or pelleted seeds sown in depressions of the phenolic foam trays with fine (No. 5) vermiculite compared to leaving the seeds uncovered, and soaking the trays in hydroponic solution rather than water, increased seedling shoot fresh weights. Seeds sown on their first day of germination or primed seeds gave greater seedling shoot fresh weights than pelleted seeds. However, the more uniform seedling shoot fresh weights from germinated seeds than from primed seeds was associated with more rapid and synchronous seedling emergence.
LOWEST SURVIVAL TEMPERATURE (LST) ESTIMATES FOR KALMIA LATIFOLIA (L.) AS AFFECTED BY NUCLEATION/SEEDING TREATMENTS
Authors: Wachter John , Cappiello Paul E.
Published: February 2019

Terminal stem cuttings of Kalmia latifolia were collected from wild plants (Milford, N.H.) on 12 Nov. and transported on ice to Orono, Maine, for analysis. Samples were processed as follows: 1) stems wrapped in dry cheesecloth; 2) stems wrapped in moist cheesecloth; and 3) stems seeded with crushed ice and wrapped in moist cheesecloth. Prepared samples were subjected to freezing tests to a low temperature of –36C. Following two weeks of incubation at 21C, samples were evaluated for leaf, petiole, stem, and vegetative bud damage. Evaluation of frozen samples revealed: 1) stem tissue remained undamaged to –36C; 2) leaf damage was inconsistent across all handling methods, with no clear LST estimate, and ice seedinggenerally resulted in increased tissue damage; 3) LSTs for vegetative buds and petiole bases were –18C and –15C, respectively, and both yielded definitive and consistent results across all treatments. The results indicate bud and petiole tissue to be the best to use for future studies on LST estimates in Kalmia latifolia.
EVALUATION OF PODISUS MACULIVENTRIS (HETEROPTERA: PENTATOMIDAE) FOR CONTROL OF THE COLORADO POTATO BEETLE ON POTATOES GROWN UNDER ROWCOVER
Authors: Hiskes Rose , Ashley Richard
Published: February 2019

Posisus maculiventris, a Colorado potato beetle (CPB) predator native to Connecticut, is commercially available. This research evaluated Podisus' effectiveness against CPB at different predator-to-prey ratios. Field experiments were conducted over two summers. The first summer yields in the treatment with 100 CPB eggs and 6 predators and the control (0 CPB eggs and 0 predators) were significantly higher than treatment with 100 CPB eggs and 0 predators. The second summer yield for treatment with 100 CPB eggs and 12 predators and the control were significantly higher than the remaining treatments with 0, 3, and 6 predators. Podisus maculiventris holds promise for control of CPB on potatoes grown under rowcover. Further research, determining the effects of all native CPB predators as pesticides more favorable to them are used, is needed.
SUSTAINING CROP GROWTH WITH COMPOST AND PLASTIC MULCH
Authors: Wells Otho S. , Mitchell James R.
Published: February 2019

In 1992 and 1993, a run-down, infertile field was treated with 0, 12, 24, and 48 T/A (day weight) of compost. Timothy was grown on the plots each year and removed. In 1994 and 1995, `Earliqueen' muskmelon was grown in the same plots, along with four types of synthetic mulch (black plastic, IRT-100 plastic, IRT-200 plastic, and paper). Over the two years, there was a consistent crop response. As compost rates increased, crop yield increased. The highest yields were with the higher rates of compost coupled with the IRT mulches. After 2 years of cropping, the soil nutrient status remained at acceptable levels at the 24 and 48 T/A rates of compost. Generally, organic matter, pH, and CEC increased with increasing compost rates. Foliar diseases were suppressed with the compost at all rates.
GROWTH AND YIELD OF GREENHOUSE TOMATO WITH CONSTANT OR INTERMITTENT HEATING OF THE ROOT AND SHOOT
Authors: Gent M.P.N. , Ma Y.Z.
Published: February 2019

What is the effect of constant compared to intermittent heating of the shoot and root on growth, nutrient status, and yield of greenhouse tomato (Lycopersicon esculentum Mill)? Seedlings were transplanted early, on 4 Mar. 1994 and 1 Mar. 1995, or late, on 25 Mar. 1994 and 31 Mar. 1995, into troughs of peat-lite mix. The troughs were heated to 21C by buried tubing, either constantly, or for 12 h during the day or the night, or they were not heated. The greenhouses had either 14/14C or 22/6C day/night minimum air temperatures. After 2 weeks, early transplants had the greatest leaf weight with constant root heat and least with no heat. Root weight was greater for 14/14C than 22/6C air heat. With 14/14C air heat, only the no-root heat reduced leaf weight, whereas with 22/6C air heat, root heat ranking was constant > day > night ≈no heat. With late transplants, only the no heat reduced leaf weight. Most nutrient concentrations were less in late than in early transplants. Number of fruit, and number and weight of marketable fruit produced by 1 July from early transplants was affected by root heat; the ranking was constant heat > day > night > no heat. The 22/6C air heat increased marketable yield because of fewer small, irregular and blossom end rot fruit. Root heat had no effect on yield of late transplants.
GROWTH AND N AND C METABOLITES OF TOMATO IN RESPONSE TO ROOTS WARM DURING THE DAY AND COLD AT NIGHT, OR VICE VERSA
Authors: Ma Yong-Zhan , Gent Martin P.N.
Published: February 2019

How are C and N metabolites affected by a root-zone temperature (RZT) in phase or out of phase with the photoperiod? Tomato (Lycopersicon esculentum Mill.) was grown with an air temperature of 20C, and RZT that was in phase with a 12-h photoperiod, 28C in the light and 12C in the dark, or out of phase, 12C in the light and 28C in the dark. Seedlings were grown in flowing solution containing 200 μm NO3 and excess amount of other mineral elements. The flow rate increased with plant size. After 8 days, plants were harvested at the end of the day and at the end of the night. The relative growth rate (day–1) was slightly greater for in-phase (0.19) than out-of-phase RZT (0.17) and less than that at a constant air and RZT of 24C (0.22). RZT affected N accumulation and partitioning of C and N metabolites. Cool roots contained more NO3 and free sugars than warm roots. Leaves had less NO3 in the light than in the dark, and NO3 in leaves of plants with an out-of-phase RZT was depleted in the light. Concentration of free amino acids and protein was greater and the amount of starch was less in leaves of plants with in-phase RZT.
EFFECTS OF ETHEPHON AND AVG ON FRUIT CUTICLE OF `DELICIOUS' APPLES
Authors: Ju Zhiguo , Bramlage William J.
Published: February 2019

Cuticle provides a barrier for secretory of volatile lipophilic metabolites like α-farnesene in fruit. The accumulation and oxidation of α-farnesene or the propagation of its oxidation products can be affected by the thickness, the constituents, and the structure of this cuticle. To measure the development changes of cuticle components, `Delicious' trees were treated separately with 250 ppm aminoethoxyvinylglycine (AVG) on 12 Sept. and 200 ppm ethephon on 19 Sept. Fruit were harvested on 28 Sept. and stored at about 20C for 6 weeks. Total wax in both treatment and control fruit at harvest was around 2.8 mg/f.fr.wt. It increased rapidly after 2 weeks and reached 8.4 mg/g fr.wt. in control fruit after 6 weeks, which paralleled increasing internal ethylene and accumulation of α-farnesene. Ethylene synthesis, α-farnesene, and total wax accumulation were enhanced by ethephon treatment and completely suppressed by AVG treatment during the whole period of storage. The cutin contents in fruit from treated fruit and the control were similar at harvest, and they remained constant during storage.
RFLP TAGGING OF CUCUMBER MOSAIC VIRUS RESISTANCE GENES IN PEPPER VIA DISTRIBUTIONAL EXTREME ANALYSIS
Authors: Zhang Yiping , Lackney Vince , Kyle Molly
Published: February 2019

We report the detection of molecular markers linked to polygenic recessive resistance to cucumber mosaic virus (CMV) in pepper using distributional extreme analysis. A total of 132 mapped tomato genomic, cDNA, and pepper genomic clones from different linkage groups in two existing pepper maps, especially from the ones showing tentative CMVR QTLs, were selected as hybridization probes for Southern blots, in which DNA from the 12 most resistant and 15 most susceptible individuals from a large segregating F2 were probed. Several clones appeared to cosegregate with CMV resistance phenotype. Further analysis is being done to place these markers on existing molecular linkage maps. The precise locations of resistance genes can be defined by examining additional markers within the region. The availability of closely linked DNA markers may facilitate marker-aided selection in pepper CMV resistance breeding programs.
A DEMONSTRATION OF HORTICULTURAL CROP PRODUCTION ON A RECLAIMED SURFACE MINE SITE IN SOUTHERN WEST VIRGINIA
Authors: Coffindaffer-Ballard Donna , Bearce B.C. , Skousen J. , Lambert G.
Published: February 2019

A 0.2-ha reclaimed minesoil site near Welch, W.Va., was amended with sewage sludge, hardwood bark, and a sorghum–sudan hybrid green manure crop to demonstrate production of horticultural crops. A selection of crops, including white birch, forsythia, zinnia, tomato, yarrow, red raspberry, and strawberry, was planted and grown. Plant growth and development, including flower and fruit production, tended to be enhanced by sludge-amended soils and reduced in green manure and hardwood bark–amended soils. Sludge increased pH, Ca, P, and Mg levels above that in the other treatments. Hardwood bark increased Mn but decreased P. The green manure amendment increased soil Fe content. In 1994 `Allstar' strawberry yield and berry weights were similar for all plots, but yield was about 10% of expected and was very close to the economic break-even point. Third-year yield of 1992 planted `Heritage' raspberries was about one-half the expected yield of 5000 lbs/acre, but still considered profitable. Zinnia flower production yielded a calculated 32% return on investment. Assuming that 50% forsythia plants were saleable in 2 years, return on investment was projected to be 30%. For white birch, assuming half were saleable in 4 years, a 16% return on investment was projected.
EFFECT OF WATER STRESS ON HEAT STRESS TOLERANCE IN GERANIUM
Authors: Arora Rajeev , Pitchay Dharmalingam S. , Bearce Bradford C.
Published: February 2019

This study evaluated the effect of reversible water stress on heat stress tolerance (HST) in greenhouse-grown geraniums. Water stress was imposed by withholding irrigation until pots reached ≈30% (by weight) of well-watered (control) plant pots, and maintaining this weight for 7 days. Control plants were watered to just below field capacity, every other day. Leaf xylem water potential (LXWP, MPa), leaf-relative water content (LRWC,%), media water content (MWC, % fresh weight), and heat stress tolerance (HST, LT50) were determined for control and stressed plants. HST (LT50), defined as temperature causing half-maximal percent injury, was based on electrolyte leakage from leaf disks subjected to 25 to 60C. Control-watering was restored in stressed plants and above measurements made after 7 days of recovery. Data indicate: 1) LXWP, LRWC, and MWC in control and stressed plants were –0.378 and –0.804 MPa, 92.31% and 78.69% and 82.86% and 15.5%, respectively; 2) HST increased significantly in stressed as compared to control plants (LT50 of 55C vs. 51C); 3) control plants were near maximally injured by 53C treatment and sustained more than 3-fold greater injury than stressed plants at 53C. In recovered plants, LXWP and RWC reversed back to control levels, paralleled by loss of higher HST.
GROWTH OF PETUNIA, IMPATIENS, AND IVY AND ZONAL GERANIUMS IN ROOT MEDIA CONTAINING COAL BOTTOM ASH
Authors: Pitchay Dharmalingam S. , Bearce B.C.
Published: February 2019

Petunia and impatiens seedlings were planted in cell packs containing 0%, 25%, or 50% (by volume) coal bottom ash (CBA) mixed with peat: vermiculite. High soluble salts caused fresh and dry weights to be greatly reduced in 25% and 50% CBA. This was thought to be due to insufficient drainage in the shallow cell packs. Subsequent crops were grown in 4-inch pots. Double Pink impatiens in 4-inch pots showed no significant difference between control and ash media in the number of buds and flowers, plant heights and diameters, and fresh and dry weights. For `Mixed Shady Lady' impatiens, the number of flowers, and fresh and dry weights were greater in the control and 50% CBA. Plant heights were reduced in 25% and 50% CBA media. There were no differences in plant diameters among the media. Ivy geraniums showed no significant difference in the number of days from planting to first bloom and 50% florets opening; number of florets, buds, and inflorescences; and stem lengths. Shoot numbers were reduced in 25% and 50% CBA. There was also no significant difference in number of days from planting to first bloom and 50% florets opening, or number of buds and inflorescences for zonal geraniums. Number of florets increased for zonal geraniums in 25% CBA.
EVALUATION OF A SPRAY FORMULATION OF CODLEMONE FOR MATING DISRUPTION OF CODLING MOTH (CYDIA POMONELLA) IN APPLE (MALUS PUMILA MILL.)
Authors: Call Robert E. , Jenkins Jack W.
Published: February 2019

Mating disruption of codling moth using codlemone pheromoneemitting twist-ties or cards has become a standard practice in many orchards. This study was initiated to determine the effectiveness of NoMate CM EC, a spray formulation of codlemone pheromone. Treatments were applied 20–21 Apr. 1995 to plots measuring 99 × 244 m of 15-year-old `Golden Delicious' apple trees on seedling rootstock. Trees were spaced 3.7 × 5.5 m and treatments were made in a randomized complete block design replicated three times. Whole trees were sprayed to run-off using a handgun. Treatments were 20.2 g a.i. NoMate CM EC/h and a watered sprayed control. Two pheromonebaited, sticky traps were placed in each replicate to monitor codling moth activity. Moth counts were made 3 days after treatment and continued twice weekly for 4 weeks. Results indicated very little moth activity for the first 14 days of the study in plots treated with NoMate CM EC when compared to the control. However, after the first two weeks differences between treatments were not significant.
LOW QUALITY, LOW QUANTITY WATER USED—CONTAINER PLANT PRODUCTION
Authors: Green James L.
Published: February 2019

Since initiation of the research in 1990, diverse plants (92 genera from 47 families) have been grown in the closed, insulated pallet system (CIPS). Greater growth has occurred in various embodiments of the CIPS than in the open container system (OCS) controls. Branching of roots, and of shoots of some plants, is greater in CIPS. CIPS is a closed system; there is no circulation of irrigation solutions nor effluent discharge from CIPS. Water and fertilizer movement in CIPS is plant-driven, and use is 10% of that applied in overhead sprinkler fertigation of open containers. Tomato plants are more tolerant of saline irrigation water, and greenhouse tomato production is more profitable in CIPS than in the OCS. CIPS provides several pest management alternatives.
EFFECTS OF HIGH-SULFATE IRRIGATION WATER ON BEAN AND BROCCOLI
Authors: Drost D.T. , Macadam J.W. , Dudley L.M. , Soltani N.
Published: February 2019

Groundwater, contaminated with sulfur (S) at concentrations higher than allowable for drinking water, may be suitable for irrigation. Our objectives were to determine the growth response and mineral uptake of two vegetables grown in high-S irrigation water. Bean (Phaseolus vulgaris) and broccoli (Brassica oleracea L.), grown in 8-L pots containing a calcareous sandy loam, were irrigated with waters containing from 58 to 582 mg S/L. Plants were harvested and growth was measured at 4, 8, or 12 weeks. Soil paste extracts and dry plant tissue were analyzed by inductively coupled plasma (ICP) spectroscopy at each harvest. Bean shoots and pod dry weight decreased by 32% and 28%, respectively, as S concentration increased. Although final pod number was not affected by the irrigation treatments, pod yields (4 weeks) decreased as S concentration increased. Broccoli growth was not affected by increasing S concentration at any of the harvest dates, though head diameter did decrease as S increased. Magnesium, sodium, and sulfur accumulated in shoot tissue (leaves and stems) of both species in proportion to their concentration in the irrigation water. It appears that high-S waters can be used to grow these vegetables without negative effects on growth.
EVALUATION OF FUNGICIDES FOR CONTROL OF BOTRYTIS SOIL LINE ROT IN SEED ONIONS
Authors: Butler Marvin D. , Crowe Fred J.
Published: February 2019

Fungicides, including Topsin M, Rovral, Ronilan, Ridomil/Bravo, TD 2350-1, CGA 219417, and a combination of Topsin M and TD 2350-1, were evaluated for control of Botrytis allii in a commercial field of hard, yellow, seed onions near Madras, Ore. The 10 × 25-ft split-plots were replicated three times in a randomized complete block design, with half the plot planted with Topsin M-treated seed prior to planting. Plots received a single fall fungicide application on 30 Sept. 1994, and two spring applications on 3 May and 13 May 1995. Stand counts were taken 4–6 Nov. 1994 and 21 Apr. 1995 to evaluate reduction in plant population over winter. Three row-foot of plants grown from untreated seed were removed and examined for lesions and sporulation 15–19 June 1995. Thirty-plant samples were taken from both plots with treated and untreated seed 17–21 July 1995. Botrytis was considered present if lesions plus sporulation were observed on the bulb at the time of sampling, or if sporulation developed on previously non-sporulating lesions within 3 days of storage in plastic bags at room temperature. A visual rating of plants that remained standing due to adequate root systems was conducted 24 July 1995. Bulb evaluation of non-seed-treated plots on 15–19 June indicated significant control of botrytis with TD 2350-1 over plots not receiving foliar fungicide application. Evaluation of non-seed-treated plots on 17–21 July indicated Topsin M, TD 2350-1, and a combination of the two fungicides provided significant disease control compared to plots without foliar application of fungicides. There were no significant differences between fall and spring stand counts, or between treated and untreated seed.
COMPARISON OF LONG-TERM STORAGE IN CHEMICAL FIXATIVES ON MORPHOLOGY AND ANATOMY OF SUPERDWARF WHEAT
Authors: Campbell W.F. , Strickland T. , Salisbury F.B. , Hole P.S. , Gillespie L. , Levinskikh M. , Ivanova I.
Published: February 2019

Wheat (Triticum aestivum L. cv. SuperDwarf) plants grown in the microgravity of space aboard the Russian space station Mir and sampled for morphological and anatomical comparison to those ex-posed to gravity on earth will be stored in chemical fixative for relatively long periods of time. Our objective was to examine, evaluate, and verify that the integrity of the vascular system and cellular components of wheat plants is maintained following storage in a chemical fixative. In ground-based studies, wheat seedlings were harvested on days 9, 28, and 68 and preserved in 4% formaldehyde: 1% glutaraldehyde (4F: 1G) fixative, adjusted to pH 7.2. Samples of leaves and/or stems were taken from these stocks after various times in storage (24 h, 1, 6, 12, and 24 months), dehydrated, and embedded in Spurr's resin. Semi-thin (1 μm) and thin (50–70 nm) sections were examined by light and transmission electron microscopy. Overall, there seems to be no major artifacts in the cellular structure. The plasmalemma and other organelles appeared normal in this fixative. Use of differential chromophores suggests that enzyme localizations at both the light and electron microscopical levels are not adversely affected by long-term storage. (Supported by NASA Grant NCC 2-831 and the Utah Agr. Expt. Station.)
A Whole-plant, Open, Gas-exchange System for Measuring Net Photosynthesis of Potted Woody Plants
Authors: Miller D.P. , Howell G.S. , Flore J.A.
Published: February 2019

Chambers were constructed to measure gas exchange of entire potted grapevines (Vitis vinifera L.). The plant enclosures were constructed from Mylar film, which is nearly transparent to photosynthetically active radiation. Maintaining a slight, positive, internal pressure allowed the Mylar chambers to inflate like balloons and required no other means of support. The whole-plant, gas-exchange chamber design and construction were simple and inexpensive. They were assembled easily, equilibrated quickly, and did not require cooling. They allowed for the measurement of many plants in a relatively short period. This system would enable the researcher to make replicated comparisons of treatment influences on whole-plant CO2 assimilation throughout the growing season. While CO2 measurement was the focus of this project, it would be possible to measure whole-plant transpiration with this system.
Turfgrass Wear Stress: Effects of Golf Car and Tire Design
Authors: Carrow R.N. , Johnson B.J.
Published: February 2019

A turfgrass wear injury study was conducted at Griffin, Ga., on `Tifway' bermudagrass (Cynodon dactylon × C. transvaalensis) using two golf car tires and three golf car types driven in a semicircular pattern to deliver 85 passes over the tread path plot area. Wear injury for the 14 days after wear was applied was assessed by visual quality, percent green coverage, leaf bruising, and verdure. Golf tire × car interactions occurred, but more wear occurred with the low pressure (48 × 103 Pa), dimpled tread tire with flexible sidewalls than the commonly used bias ply (4-ply), V-shaped tread tire with more rigid sidewalls. Significant differences in wear damage occurred for golf car type but were influenced by tire design. Thus, selection of golf car tire and golf car type can influence the degree of wear injury on turfgrass sites.
Dikegulac, but Not Benzyladenine, Enhances the Aesthetic Quality of Boston Fern
Authors: Carter Johnny , Singh Bharat P. , Whitehead Wayne
Published: February 2019

Greenhouse studies conducted in 1990 and 1991 evaluated the influence of dikegulac and benzyladenine on frond initiation and vegetative growth of Boston fern [Nephrolepsis exaltata (L.) Schott `Compacta']. Four weeks after transplanting, fern liners were sprayed with aqueous solutions of dikegulac (0, 250, 500, or 750 mg·L–1) or benzyladenine (BA; 0, 50, 100, or 150 mg·L–1). The effect of dikegulac and BA on the number of shoots, frond length, leaf area, and dry weight was measured. Dikegulac stimulated shoot initiation and increased leaf area and dry weight without affecting frond length. BA reduced frond length and had no effect on shoot initiation and dry weight. This study suggests dikegulac has potential to improve the appearance and aesthetic quality of Boston fern. Chemical names used: 2,3:4,6-bis-0-(1-methylethylidene)-α-l-Xylo-2 hexulofuranosonic acid (dikegulac); N-(phenylmethyl)-1H-purine-6-amine (benzyladenine).
Relative Susceptibility of Pecan Cultivars to Zonate Leaf Spot
Authors: Reilly C.C. , Wood B.W. , Hotchkiss M.W.
Published: February 2019

Zonate leaf spot (ZLS) [Cristulariella moricola (Hino) Redhead (C. pyramidalis Waterman and Marshall)] on pecan [Carya illinoinensis (Wangenh.) K. Koch.]—associated with unusually wet weather during June, July, and August—occurred across much of Georgia during Summer 1994. Scott–Knott cluster analysis indicated that 27 of 36 evaluated genotypes exhibited little or no field susceptibility to ZLS. `Moneymaker' exhibited the greatest susceptibility of all cultivars studied, with `Cape Fear', `Elliott', `Sumner', and `Sioux' segregating to exhibit moderate susceptibility. An evaluation of commercial orchards indicated susceptibility of major southeastern cultivars as `Desirable' < `Stuart' < `Schley' < `Moneymaker'. Control of ZLS in commercial orchards using standard fungicide spray strategies appeared to be generally ineffective.
Ornamental Cherry Tolerance of Flooding and Phytophthora Root Rot
Authors: Jacobs K.A. , Johnson G.R.
Published: February 2019

Seedlings of eight Prunus taxa were evaluated for variation in susceptibility to a single, 4- or 5-day flooding period and root rot caused by Phytophthora cryptogea Pethybr. & Lafferty. Survival, plant defoliation, disease severity index, root necrosis, and net photosynthesis indicated that the combination of flooding and pathogen was significantly more severe to all taxa than either individual treatment. Most response variables reflected early plant dysfunction but were not correlated with long-term survival. Long-term survival was 70% in the combination treatment compared to 99% in the control group. Flooding injured seedlings more than the pathogen in most taxa. Taxa differed only slightly in tolerance to the treatments, as measured by survival rate. Prunus takesimensis Nakai had the highest survival rate of 100% and along with P. mahaleb L. and P. yedoensis Matsum. showed some tolerance to flooding and the pathogen. Prunus sargentii Rehd. had the lowest survival rate of 81% and appeared to be least tolerant to the pathogen.