bluuebunny/crossref_metadata_2025 huggingface dataset:
Measuring Root Surface Area and Mean Root Diameter of Peach Seedlings by Digital Image Analysis
Authors: Tagliavini M. , Veto L.J. , Looney N.E.
Published: February 2019

Using area profile integration software and an image processing system, we reliably estimated total root surface area of intact each [Prunus persica (L.) Batsch.] seedlings by 1) producing high-quality monochromatic video images under preset and constant conditions; 2) determining a threshold gray intensity value that differentiates the finest roots on the image; 3) producing a binary image where all pixels with gray values above the threshold are black; 4) determining the proportion of black pixels on the 480× 512-pixel matrix; and 5) multiplying this two-dimensional root surface value by π to estimate total root surface area. Normalized intensity (an average intensity weighted according to the proportion of the binary image in each gray scale class) was calculated using software that superimposed the video image on the binary image and was used to estimate mean root diameter. Evidence of reliability and examples of the use of both estimates are provided.
Yield and Fruit Size of `Bluecrop' and `Blueray' Highbush Blueberries at Three Plant Spacings
Authors: Moore James N. , Brown Maurus V. , Bordelon Bruce P.
Published: February 2019

The influence of in-row plant spacing on the yield and fruit size of `Blueray' (erect growing) and `Bluecrop' (spreading) highbush blueberry (Vaccinium corymbosum L.) was studied. Plants of both cultivars, spaced at 0.61 m within the row, had significantly higher yields per hectare than plants grown at wider spacings (0.92 and 1.22 m) in each of five harvest years. On a per-plant basis, however, plants spaced at 1.22 m had higher yields in the last two harvest years of the experiment than plants spaced more closely, which indicated that interplant competition reduced per-plant yields of closely spaced plants as plants grew larger. Over the 5-year harvest period, plots with 0.61-m plant spacing produced a cumulative total yield of 17.24 t·ha more than plots with the conventional 1.22-m spacing. Plant spacing did not affect fruit size in this experiment.
Municipal Solid Waste Compost Suppresses Weeds in Vegetable Crop Alleys
Authors: Roe Nancy E. , Stoffella Peter J. , Bryan Herbert H.
Published: February 2019

A mulch of municipal solid waste compost at 224 t·ha was compared with glyphosate sprays and a nontreated check for weed control in vegetable crop bed alleys during Spring and Summer 1992. In both experiments, there was a significantly lower percentage of weed coverage in the compost mulch and herbicide spray plots than in the control plots. Weed control in the compost and herbicide treatments was similar. In the spring experiment, tractor tire traffic through the alleys reduced weed growth in all plots by 62 % and 44% at 16 and 73 days after treatment initiation, respectively. These results suggest that municipal solid waste compost may have potential as a viable mulch for weed control in vegetable crop alleys. Chemical name used: isopropylamine salt of N -(phosphonomethyl) glycine (glyphosate).
“Peach and Nectarine Varieties”-A Hypertext Index
Authors: Okie W.R.
Published: February 2019

“Peach and Nectarine Varieties” is a self-contained computer program describing more than 600 varieties and their performance in the southeastern United States. The information can be accessed in various ways, including searching for any word or name. A Master Index of names and synonyms lists more than 6000 names used in the United States, plus many foreign names. This index includes pedigree, origin, and a coded description. General information is included regarding peaches and nectarines. All North American breeding programs are chronicled. The program is available for MS-DOS computers with an EGA or VGA monitor, and may be freely distributed.
Controlling Powdery Mildew in Euonymus with Polymer Coatings and Bicarbonate Solutions
Authors: Ziv O. , Hagiladi A.
Published: February 2019

Powdery mildew in euonymus (Euonymus japonica Thunh.) plants, caused by Oidium euonymi-japonica (Arcang.) Sacc., was controlled by applying various polymer coatings or an aqueous solution of sodium or potassium bicarbonate plus horticultural Sun Spray (SS) Ultra Fine Oil 1% (v/v) to plant foliage. The combined treatment (bicarbonate + oil) was more effective than either of the two materials alone. The results indicate that sodium or potassium (but not ammonium) bicarbonate solutions mixed with SS seems to be a useful biocompatible fungicide for controlling powdery mildew in euonymus plants. Some of the polymer coatings effectively reduced disease levels when applied immediately after the symptoms first appeared.
Adsorption, Desorption, and Leaching of Oxadiazon in Container Media and Soil
Authors: Wehtje Glenn R. , Gilliam Charles H. , Hajek Ben F.
Published: February 2019

Adsorption of 14C-labeled oxadiazon was evaluated in three soilless media and a mineral soil at concentrations between 0.1 and 100 mg·kg-1. Adsorption, which was at least 96%, was not influenced by absorbent type (medium vs. soil) or by oxadiazon concentration. However, desorption was greater in the media than in the soil. After five water extractions, 5.4% of the applied oxadiazon was recovered from media, but only 0.4% was recovered from the soil. In the soil and in two of the media, leaching with water failed to displace oxadiazon 2 cm below the surface to which it had been applied. No oxadiazon was detected below 4 cm in the third medium. Oxadiazon is sufficiently adsorbed to resist leaching-based displacement. Oxadiazon is not likely to enter the environment by escaping from treated containers. Chemical name used: 3-[2,4-dichloro-5-(1-methylethoxy)phenyl]-5-(1,1-di-methylethyl)-1,3,4-oxadiazol-2-(3H)-one (oxadiazon).
Armillaria Infection and Water Stress Influence Gas-exchange Properties of Mediterranean Trees
Authors: Loreto Francesco , Burdsall Harold H. , Tirro' Alfio
Published: February 2019

The effect of inoculating seedlings of Mediterranean cultivated trees grown under greenhouse conditions with North American isolates of Armillaria mellea (Vahl: Fr) Kumm. and A. ostoyae (Romagn.) Herink on net photosynthesis (A), stomatal conductance (gs), and water potential was examined. The effect of water stress was determined also on the same plant species independently and in combination with Armillaria infection. Red oak (Quercus rubra L.) was used as a control to indicate Armillaria virulence on North American trees. Carob (Ceratonia siliqua L.) was resistant to infection. Infection was successful in sour orange (Citrus aurantium L.), but A, gs, and water potential were unchanged over the 60-day experiment. In olive (Olea europea L.) and oak, A and gs were reduced following inoculation with A. mellea. A and gs of all species but carob were reduced under water stress. Olive and oak responses to water stress and Armillaria infection were quantitatively similar; however, the two stresses combined did not reduce A and gs further. Red oak was strongly susceptible to A. ostoyae infection, but Mediterranean trees were not infected by the same Armillaria isolate. Our results show that Armillaria infection may reduce A and gs in susceptible species.
EFFECTS OF CARBON DIOXIDE ENRICHMENT AND IRRADIANCE ON EX VITRO ROOTING, ACCLIMATIZATION AND SUBSEQUENT GROWTH OF MICROPROPAGATED APPLE AND BLUEBERRY.
Authors: Pritts Marvin , Isuta Dorcas
Published: February 2019

Previous findings reveal that rooting and acclimatization of apple and blueberry plants is often difficult, inconsistent and inefficient. This experiment was set up in a fog chamber lo investigate the effects of CO2 enrichment (CDE) and irradiance on unrooted stage II microshoots. Two CO2 and 3 light levels tested were: 1350 +/- 150 (+ CDE), and 450 +/- 50 (- CDE) ppm; 30 +/- 5 (low), 55 + 10 (medium), and 100 + 20 (high) umolm-2s-1 respectively. Cultivars assessed were Berkeley and Northsky for blueberry. G65 and NY30 for apple. Blueberry microshoots acclimatized successfully and gave between 90 to 100% rooting and survival rate. Apple microshoots acclimatized and rooted slowly, exhibited great sensitivity to in vivo conditions and gave between 40 to 100% rooting and survival rate. High light induced photo-inhibition which disappeared after complete acclimatization. There was a significant difference between low light and the other two light levels. The effect of CDE was dependent on cultivar. In most cases, high light (-) CDE gave the most vigorous growth (highest plant dry weight and leaf area). There was a significant difference between (+) CDE and (-) CDE at low and medium light, but none at high light. Low light (-) CDE and medium light (+) CDE were superior over low light (+) CDE and medium light (-) CDE. respectively. Stalling out in apple microshoots was corrected by GA sprays.
WARMING APPLES DURING COLD STORAGE: ITS POTENTIAL AS A NON-CHEMICAL PROCEDURE TO REDUCE LOSSES FROM SUPERFICIAL SCALD
Authors: Bramlage William J. , Watkins Christopher B.
Published: February 2019

Seeking non-chemical alternatives to use of DPA for scald control on apples, we interrupted storage with a brief warming period. This often reduces chilling injuries of fruit. Warming `Granny Smith apples for 5 days at 20 C after 2 weeks at 0 C reduced scald as effectively as a 1000 ppm DPA treatment at that time. To better characterize this response, we tested other timings of the warming period, and also lower warming temperature. Warming at 10 C, or for shorter times at 20 C, or after longer periods at 0 C all were less effective. Maintaining a warm period before storage was not effective. During warming of `Cortland' and `Delicious' apples softening and loss of green color occurred, the extent of which increased with warming time and usually was greater if the fruit had initiated the ethylene climacteric before warming.
STRAWBERRY GROWTH AND DEVELOPMENT IN THREE MINESOILS AMENDED WITH SLUDGE, HARDWOOD BARK OR A SUDAN-SORGHUM GREEN MANURE CROP.
Authors: Ballard Donna , Popenoe Juanita , Bearce Bradford , Skousen Jeffrey
Published: February 2019

Strawberry (Fragaria × Anaassa cv. Tribute) plants were planted in 15 cm standard pots filled with overburden soils from three West Virginia surface mine sites. Initial pH levels were 6.5, 4.4, and 3.6. Prior to planting pH levels were adjusted with CaCO3 to 6.5-6.7 in each soil. Each soil was amended by mixing in 60.85 g/pot (62.5 dry kg/ha) of sewage sludge, Sudan-sorghum hybrid green manure crop, hardwood residues, or unamended. A dry fertilizer (.10-.045-,089, N-P-K) was also mixed into the soil at a rate of 0.5 g/pot (454 kg/ha). Plants were grown from 3-6 to 10-16, 1992, on which date harvests and measurements were performed. The sludge treatments significantly increased fresh and dry weight accumulation, number of leaves, leaf area, and number of runners per plant above that of the control plants. The hardwood residues amendment delayed first date of ripe fruit and decreased average fruit fresh weight in one of the soils. Hardwood residues also decreased leaf number in another soil. The pH levels were raised to 6.8-7.3 by the sludge in all soils and remained at or near these values during the growing period.
MATRIC AND OSMOTIC PRIMING OF PURPLE CONEFLOWER
Authors: Crossan Cynthia , Pill Wallace
Published: February 2019

Seeds of purple coneflower (Echinacea purpurea (L.) Moench were osmotically primed (OSP) in polyethylene glycol (PEG) or matrically primed in expanded vermiculite No. 5 (solid matrix priming, SMP). With both OSP or SHP at 15C, 10-day exposure to -0.4 MPa resulted in lowered time to 50% germination (T,) and higher germination percentage than shorter exposure (5-day) or lower water potential (-1.5 MPa). SMP- and OSP-seeds performed similarly in a greenhouse trial, resulting in 80% and 34% seedling emergence at 23C and 37C, respectively, compared to 58% and 27% for non-primed seeds. Seedling emergence rate and synchrony from primed seeds were greater than from non-primed seeds at both temperatures. An incubator study established that adding 10-4M GA3 and 10 mN ethephon (2-chloroethylphosphonic acid) to the PEG or vermiculite resulted in lower T50 and higher germination percentage than priming without these growth regulators. A further incubator study established that less-expensive trade products (Pro-Gibb Pius 2X) and Florel could substitute for the reagent-grade growth regulators. Seeds primed in PEG or vermiculite containing 10-4M GA3 from Pro-Gibb Plus 2X and 10 mM ethephon from Floral had lower T50 and higher percentage emergence in a greenhouse trial than seeds primed without growth regulators. Compared to the non-primed seeds, these treated seeds had 29% greater seedling emergence and 61% less time to 50% emergence.
FERTILIZATION OF TWO WOODY SPECIES WITH FISH HYDROLYZATE FERTILIZER
Authors: Cappiello Paul E.
Published: February 2019

The effect of a fish hydrolyzate fertilizer product on growth of Acer rubrum and Pseudotsuga menzeisii was studied. Bare root plants were fertilized at a rate of 90, 180, and 270 kilograms of N/hectare. Soil samples were collected every two weeks throughout the summer and were analyzed for nutrient content. In addition, August leaf samples were collected and analyzed for N, P, and K content. Growth measurements on Acer rubrum indicate that stem caliper was significantly increased by all fertilizer treatments over the control trees. The granular fertilizer produced a significant linear increase in caliper growth with respect to fertilizer rate. Shoot growth was also significantly increased by all fertilizer treatments; however, as with caliper growth, the granular fertilizer treatments resulted in the greatest and most consistent response. The response of Pseudotsuga menzeisii showed significant increases in shoot growth and stem caliper but results were not as consistent as in the case of the maple.
EVALUATION OF DISPLAY LIFE AND ETHYLENE SENSITIVITYOF POTTED RASTER CACTUS AND HOLIDAY CACTUS
Authors: Scott Deidre , Han Susan S. , Boyle Thomas H.
Published: February 2019

The display life of individual flowers was determined for 8 cultivars of Easter cactus (Rhipsalidopsis hybrids) and 5 cultivars of Holiday cactus (Schlumbergera hybrids). For Easter cactus and Holiday cactus cultivars. the display life of individual flowers ranged from 7 to 12 days and from 4 to 6 days, respectively. In a second study, flowering plants were exposed to 0, 0.4, or 1.0 μl·liter-1 ethylene (C2 H4) for 48 h and were evaluated at 0 and 5 days after C2 H4 treatments. Plant responses to C2 H4 were dependent on C2 H4 concentration, cultivar, and stage of floral development: Easter cactus cultivars were less sensitive to C2 H4 than Holiday cactus cultivars. There was no correlation between display life of individual flowers and sensitivity to C2 H4. These studies demonstrate that: 1) there is substantial genetic variation within and between genera for postharvest performance; and 2) display life of individual flowers and plant sensitivity to C2 H4 should be evaluated when selecting for postharvest performance.
HAIL DAMAGE ON THREE VEGETABLE CROPS
Authors: Kee Edwin , Wootten Tracy
Published: February 2019

U.S. crop loss from hail damage amounted to $246,443,391 in 1991. Premiums paid for hail insurance was $403,742,507. Despite the magnitude of this industry, the effects of varying levels of hail injury at different stages of plant growth is largely unknown for many vegetable crops. To further evaluate the effects of hail on strawberries, watermelons, and sweet corn, several studies were established in 1991 and 1992. Simulated hail applications were made at different rates and stages of crop growth. Total yields and marketable yields of strawberries were reduced by hail applications. All hail treatments reduced the number of marketable watermelons, except for the vegetative size light hail treatment in 1991. In 1992, the early treatments caused the most total yield reduction. All hail treatments reduced the percentage of marketable ears of sweet corn, except for the light application in the 13th leaf stage (early vegetative) in 1991. In 1992, additional treatments consisting of clipping all leaves were conducted. Clipping leaves at the early silking stage reduced marketable ears, indicating the loss of foliage adversely affected the growth of the ear. Clipping leaves just prior to harvest reduced the yield of Jubilee, but not Silver Queen.
USE OF COVER CROPS IN VEGETABLE PRODUCTION
Authors: Mangan Francis X. , Herbert Stephen J. , Else Mary Jane
Published: February 2019

Cover crops have been used in agricultural systems for thousands of years and are still an important part of vegetable production in the Northeast. Winter rye (Secale cereale) is by far the dominant cover crop species on conventional vegetable farms in the New England states. It is use is primarily for erosion control. Winter rye is popular since it is cheap, easy to establish, can overwinter in the harsh winters of northern New England, is efficient in “capturing” excess nitrogen at the end of the cash crop season, and it can produce substantial amounts of organic matter in the spring. As many positive attributes that winter rye has, it is important to be aware of many of the other potential cover crop species that are available to us. For example, many conventional growers are exploring the use of leguminous cover crops as an alternative to chemical nitrogen fertilizers which are more readily leached and are only going to get more expensive. Cover crops can also be seeded and managed in innovative ways to suppress weeds and other pests, add organic matter and conserve soil moisture.
CHEMICAL, PHYSICAL AND SENSORY ATTRIBUTES OF FORMED AND FROZEN BAKED SWEETPOTATO
Authors: Collins J.L. , Liao J.-Y.
Published: February 2019

Sweetpotato (SP) provides culinary satisfaction and essential dietary nutrients: vitamins A and C, dietary fiber, ccmplex carbohydrates and minerals. Yet, consumption suffers from absence of convenience products. Therefore, objectives were to prepare a convenience-type product of baked SP and to measure selected properties/attributes When reheated. Jumbo, cured/stored roots of `Southern Delight' (SD) and `Carolina Bunch' (CB) were baked at 190 C/75-90 min or 204°C/70-80 min, peeled, cut into pieces, stuffed into cellulose casing, frozen and held 2 and 6 mo. Tests performed were proximate analysis, B-carotene, color and sensory. Solids, less carbohydrates, were higher in CB, the more intensely orange colored. Color was unaffected by baking or storage. Acceptability and desire to purchase were greater for CB baked at 204 C and stored 6 mo. Desirable characteristics included: availability, requiring heating only; textural integrity of baked roots; color and flavor retention to 6 mo; portion control; use of jumbo roots and potential for addition of flavorings.
EVALUATION OF FUNGAL INFECTION OF PECAN ROOTS WITH HIGH PRESSURE LIQUID CHROMATOGRAPHY
Authors: Nesbitt Monte L. , Storey J. Benton , Lyda D. , Grauke L.J.
Published: February 2019

Rootstock resistance to soil-borne phytopathogenic fungi, such as Phymatotrichum omnivorum (Shear) Duggar, is an important factor in disease control. Measurement of natural rootstock resistance is often based on plant survival/mortality percentage, and /or growth data. Fungal colonization of host roots in disease screening experiments may not be uniform for many reasons, causing variability in host response. Quantification of fungal colonization is needed in order to better understand rootstock performance. Ergosterol, a structural sterol in cell membranes of fungi, is not found in higher plants, and can thus be a measure of fungal colonization. Ergosterol was extracted from roots of pecan seedlings artificially inoculated with P. omnivorum and grown in an environmental growth chamber. Analysis of extracts with HPLC revealed that seedlings which were killed in screening, or had low root performance ratings, had increased levels of ergosterol. Non-inoculated controls also contained Ergosterol. indicating contamination and possible competition by other fungi.
PHOTOSYNTHESIS AND TRANSPIRATION DURING GROWTH AND DEVELOPMENT OF ALLIUM CEPA L.
Authors: Warnock Daniel , Randle William , Rieger Mark
Published: February 2019

Photosynthesis is the very essence of agriculture. Previous photosynthetic and transpirational studies of onion (Allium cepa) have been limited to specific developmental stages. Our study measured photosynthesis and transpiration in sixteen plants of a single short-day cultivar over an eleven week period containing both non- and bulb inductive photoperiods. Differences in weekly means for photosynthesis, leaf conductance, water use efficiency, and intercellular CO, were highly significant. Weekly photosynthetic means increased under a non-inductive photoperiod and peaked one week after initiating a bulb inducing photoperiod. A decrease and leveling period occurred as bulbs developed followed by a decrease as foliage lodged. Weekly photosynthetic and leaf conductance means were correlated and highly significant. Water use efficiency and intercellular CO, means remained fairly constant throughout the study suggesting that photosynthesis in unstressed onions was controlled by internal mechanisms instead of stomata.
STRAWBERRY PERFORMANCE USING THE ANNUAL HILL PLASTICULTURE SYSTEM IN ALABAMA
Authors: Himelrick David G. , Dozier W.A.
Published: February 2019

A number of strawberry cultivars and breeding line selections have been tested in the annual plasticulture system. The only two cultivars currently recommended based on cultural and economic performance ate 'Chandler' and 'Oso Grande'. Plant type (fresh dug, plug, etc.) and nursery source have also been evaluated. Fresh dug plants with leaves intact generally perform better than those with leaves removed. Rooted runner tips in cell packs (plug plants) look very promising and outperform fresh dug plants in most situations. Plastic mulch treatments included clear (CLR), black (BLK), laminated white on black (W/B), laminated black on white (B/W), IRT-76 (IRT), AL-OR brown (ALOR), and a bare ground (BG) check. In the first season the highest yields for 'Chandler' were obtained on IRT, followed by CLR, ALOR, B/W, BLK, W/B, and BG. The highest yields for 'Selva' were on CLR followed by BLK, ALOR, IRT, B/W, W/B, and BG. In the second season the highest yields for 'Chandler' were on W/B followed by BLK. ALOR, IRT, B/W, CLR, and BG. In the case of 'Selva' ALOR was the top performing treatment followed by IRT, W/B, BLK, B/W, BG, and CLR.
INFLUENCE OF A SOIL SPIKE AERATOR ON INCREASING NUT SIZE AND YIELD OF PECAN TREES
Authors: Chapman Dan , Sistrunk Laurence , Storey J. Benton
Published: February 2019

Objectives of this experiment were: 1) to determine what effect a soil spike aerator had on nut quality and yield, and 2) to determine whether soil compaction influenced nut quality and yield.3) to determine whether tree stress influenced nut quality or yield on pecan trees In 1990, a randomized design was set up in a 33 year old orchard on Westwood silty clay loam with 3 main treatment factors: 1990 nut size (measure of tree stress), aeration, and cultivar. Location for this experiment was the Adriance Orchard on the Texas A&M Plantation - Brazos River flood plain. Nut quality was determined by the % kernel and # nuts/kg. Yield was measured in kg per tree. Results after two years showed that aeration increased the nut size of stressed trees in 1991 and non-stressed trees in 1992 Yield was unaffected by aeration in both years but stressed trees produced lower yields in 1992. Aeration increased nut size, but not significantly from 119 nuts/kg to 111 nuts/kg in 1991. There was a significant increase with aeration in 1992 from 121 nuts/kg to 113 nuts/kg. Yield and % kernel were not significantly different for both years with aeration Stress did not increase % kernel in either 1991 or 1992 but nut size was larger on non-stressed trees for both years. Stressed trees produced fewer nuts per tree in 1992.
YIELD AND VEGETATIVE GROWTH OF HIGHBUSH BLUEBERRIES AS INFLUENCED BY IRRIGATION REGIME
Authors: Patterson W. Keith
Published: February 2019

Five year old 'Bluecrop' blueberry plants were subjected to five irrigation regimes over a two year period to determine the influence on yield, berry weight, and plant growth. The plants were in 140 liter open-ended barrels to isolate different rates of moisture application. Ten plants/treatments were utilized in this study, with each plant considered a rep. Total yields did not follow a predictable pattern. Plants receiving 12 and 16 liters of water 3x per week produced larger berries, and resulted in larger dry weights at termination of this study. Plants receiving 20 liters 1x per week produced smaller berries than other treatments, lower yields in year 2, and smallest dry weight at end of the study.
THE EFFECT OF MID-SEASON VINE REMOVAL ON THE GROWTH OF FIVE SWEETPOTATO (IPOMOEA BATATAS L.) CULTIVARS
Authors: Kahn Victor A. , Stevens C. , Mafolo T. , Bonsi C. , Lu J.Y. , Rhoden E.G. , Wilson M.A. , Brown M.J.E. , Kabwe K. , Adeyeye Y.
Published: February 2019

TU-82-155 and `Georgia-Jet' early maturing. `Carver II', TU-1892 and `Rojo-Blanco' late maturing sweetpotato, cultivars were evaluated in the field for 0.20 and 40% vine removal (VR) at 8 wk after transplanting. Parameters measured were: leaf area index (LAI) recovery, net assimilation rate, foliage crop growth rate (FCGR), storage roots crop growth rate (RCGR). alpha a (the mean relative growth rate in dry wt to the mean relative growth rate in leaf area over a time interval) or the partitioning of assimilates, total and marketable yield. A split. splitplot design was used and plants were sampled at 3 and 8 wk following VR. Except for TU-82-155 all cultivars showed significant LAI recovery above the control at 3 and 8 wk after vine removal when 20% of the vines were removed while at the 40% VR, only 'Georgia-Jet'. TU-1892 and 'Carver II' showed significant increases in LAI for the same periods. Net assimilation rate showed significant interactions while FCGR was not significantly affected by either 20 or 40 VR compared to the control at 3 or 8 wk after VR. RCGR was significantly affected by both levels of VR at 3 and 8 wk after VR and surplus assimilates (alpha a) showed significant interactions between cultivars and % VR. Told yield declined for all cultivars irrespective to maturity groups with the sharpest decrease being at the 20% VR. All cultivars except TU-82-155 showed a decrease in marketable yield, the increase in marketable yield of TU-82-155 was due to a lower non-marketable yield.
PHOTOPERIOD/LIGHT INTENSITY INTERACTIONS ON GROWTH OF TWO SWEETPOTATO CULTIVARS IN NFT
Authors: Burrell S. , Mortley D. , Loretan P. , Garner L. , Trotman A. , David P. , Carver G. W.
Published: February 2019

The effects of photoperiod and light intensity on two sweetpotato cultivars [Ipomoea batatas (L.) Lam] were evaluated in growth chambers. Vine cuttings of `TI-155' and `GA Jet' were grown using nutrient film technique (NFT) in a modified half Hoaglands solution with a 1:2.4 N:K ratio in channels (0.15×0.15×1.2 m). Plants were exposed to 9:600 or 18:300 umols m-2 s-1 photoperiod:light intensity treatments in a randomized complete block design with two replications. Temperature was set at 28:22 light:dark and RH was 70%. Storage root fresh and dry weights and fibrous root dry weight for both cultivars were significantly higher for plants exposed to longer photoperiod and lower light intensity than for those at a shorter photoperiod and higher light intensity. Foliage fresh weight for TI-155' was higher at 18:300 photoperiod:light intensity but dry weights were similar. Foliage fresh and dry weights for `GA Jet' and number of storagage roots/plant for both cultivars were similar regardless of treatments.
BACTERIAL WILT INCIDENCE IN TOMATO AS AFFECTED BY CULTIVAR AND THE DEPTH OF LIME INCORPORATION.
Authors: Ssonkko R. , Locascio S.J. , Stall R.E. , Maynard D.N.
Published: February 2019

A single lime application of 5.4 t/ha per 20 cm increment of soil to a depth of 60 cm controlled bacterial wilt (Psendomonas solanacearum E. Smith) up to 2 years in tomato (Lycopersicon esculentum Mill.) growing in a naturally infested soil. `Sunny' with 64% disease incidence, was the most susceptible, `Capitan' (20%) was intermediate, and `Caraibo' (5%) and `Hawaii 7997' (2%) were the least susceptible. Incorporation of lime 40 to 60 cm deep reduced bacterial wilt incidence in 'Capitan' by 75%, and 60% in `Sunny'. The number of bacteria in the soil was not affected by lime treatment. Soil pH and total Caincreased linearly with time and with depth of lime incorporation. Bacterial wilt control in `Sunny' and `Capitan' was associated with an increase in pH. Liming to 40 or 60 cm generally increased leaf Ca and decreased Mn, Zn, and Cu. `Hawaii 7997' contained significantly higher concentrations of Ca, Mg, and K, and lower Cu compared to 'Sunny'. `Hawaii 7997' produced significantly higher yields than the other cultivars. Deep lime incorporation increased fruit weight of `Sunny' by 184% and 'Capitan' by 79% as compared with 0 lime.
LODGING IN DIRECT SEEDED PEPPERS
Authors: McCullough M. D. , Motes J. E. , Kahn B. A. , Maness N. E.
Published: February 2019

One of the problems associated with machine harvesting of spice peppers (Capsicum annuum L.) is plant lodging. Factorial combinations of four bedding treatments and two N rates were compared for effects on lodging and fruit yield of Chile at Fort Cobb and Bixby, Okla.. and of paprika at Bixby, Okla. Bedding treatments were: 1) no-bed; 2) no-bed with 5 cm of soil hilled to the bases of plants; 3) bedded preplant but bed not maintained throughout the growing season; and 4) bedded preplant and bed maintained throughout the growing season. All plots received preplant N at a low rate (45 kg ha-1). Half the plots also received a topdressing of 45 kg ha“ of N at early fruit set. No significant differences were found among the different bedding treatments for lodging. Bedding treatments one and three led to higher Chile yields at Bixby than treatments two and four. Bedding treatments one and two led to higher paprika yields than treatments three and four. Chiles showed an increase in plant height and width with the higher N rate at both locations. The higher N rate also increased plant dry matter and fruit yield in all three studies. Paprika uprooting force was greater in treatments two and four compared to treatments one and three.
CHROMOSOME DOUBLING OF Allium fistulosum × A. cepa INTERSPECIFIC F1 HYBRIDS THROUGH COLCHICINE TREATMENT OF REGENERATING CALLUS
Authors: Song Ping , Kang Wanhee , Peffley Ellen B.
Published: February 2019

Regenerating calli of Allium fistulosum × A. cepa interspecific F1 hybrids were treated in vitro with colchicine. A factorial experiment (colchicine concentration × time) was used to recover tetraploids from calli treated with colchicine in vitro. Shoot production of regenerating calli following in vitro colchicine treatment decreased with increasing colchicine concentration and treatment time. Cytological analyses of root tip cells from regenerated plantlets showed that chromosomes of control plantlets (not treated with colchicine) were not doubled. Chromosomes of some plantlets regenerated from in vitro colchicine treated calli were doubled, resulting in tetraploids. Calli treated with 0.1 or 0.2% colchicine in BDS (Dunstan & Short, 1977) liquid medium for 48 or 72 hours yielded the highest number of tetraploid plantlets. These results demonstrate that in vitro colchicine treatment of regenerating calli of interspecific F1 hybrids is effective in recovering tetraploids.
COMPOSTED POULTRY MANURE AS POSSIBLE FERTILIZER SOURCE FOR CONTAINER GROWN WOODY ORNAMENTALS
Authors: Klingaman Gerald , Wheeler G.L.
Published: February 2019

Eight species of woody nursery stock were grown in 4 liter containers and fertilized with a conventional resin-coated slow release material (at 3.5 g N per container) or composted poultry manure applied as a top dressed or incorporated with nitrogen rates ranging from 1.0 to 11.2 g N per container. In all cases the conventional resin-coated product outperformed composted poultry manure by factors of 2 to 3 times (for height, dry weight and quality score). Although a rate response was observed with the composted, even the highest rate of nitrogen application produced plants with dry weights of 1/2 that of the control. When comparing the sources of composted poultry manure alone, the 4-4-4 product outperformed the 2-2-2 compost, even with equivalent rates of nitrogen, for 3 of the 8 species studied. Incorporation proved superior to topdressing for the 4-4-4 source but topdressing was superior for the 2-2-2 material. These studies are part of a nutrient partitioning experiment being conducted to determine the fate of nitrogen released from composted poultry manure.
CUT FLOWER PRODUCTION IN NORTHEAST TEXAS
Authors: McDonald Garry V. , Pemberton H. Brent
Published: February 2019

Cut flower production in a low-input greenhouse for winter and spring holiday sales was evaluated. Low-input structure was a plastic covered Quonset greenhouse modified with sides that could be manually raised or lowered. Sides were raised on mild days for ventilation and remained closed for minimum heating for the few brief periods of sub-freezing temperatures characteristic of the local winter climate. Bulbs of tulip (Tulipa sp L.) cultivars `Maureen', `Negrita', and `Oxford' were dry cooled for 12 weeks and planted in December for Valentine's Day forcing. 30% shading did not significantly increase stem length in `Maureen' and `Oxford' but did increase stem length in `Negrita'. `Oxford' was at a harvestable stage for the. Valentine's Day market, but not `Maureen' or `Negrita'. All cultivars were of an acceptable quality. Plugs of snapdragon (Antirrhinum majus) cultivars `Appleblossom', `Potomac white', and `Rocket Rose' were planted in late winter at 4 and 6 inch spacing and were either pinched or not pinched. For all cultivars, pinching resulted in higher yield but lower grade. Four inch spacing had a slightly larger number of higher grade stems possibly due to stretching. `Appleblossom' and `Potomac White' were florist grade, whereas `Rocket Rose' was more appropriate for mass marker For both tulip and snapdragon, cultivar evaluation is necessary to determine suitable market strategy.
ESTABLISHMENT OF THE LSU AGRICULTURAL CENTER NATIVE PLANT ARBORETUM
Authors: Owings Allen D. , Johnson Charles E. , Robbins M. LeRon
Published: February 2019

Educational and research opportunities utilizing native plant species are being developed by the LSU Agricultural Center through the recent establishment of a native plant arboretum at the Calhoun Research Station. Plants indigenous to Louisiana and surrounding states are being collected and planted in the arboretum for evaluation of potential values for landscaping, in food industries, and/or wildlife management. Native trees being studied include species of oak (Quercus), maple (Acer), hickory (Carya), and dogwood (Cornus). Lesser known species of holly (Ilex) and hawthorn (Crataegus), are being evaluated for commercial production and landscape potential. Fruit being collected for field orchard studies include mayhaw (Crataegus opaca), pawpaw (Asimina triloba), and several native plums (Prunus spp.).
COTTON GIN TRASH AS A CONSTITUENT OF BEDDING PLANT MEDIA
Authors: Owings Allen D.
Published: February 2019

A greenhouse study was conducted to determine the influence of media containing varying volumetric proportions of composted cotton gin trash and pine bark on the growth of Coleus × hybridus 'Golden Bedder'. All media treatments were amended with 1.5 lbs/yd3 Micromax and 8 lbs/yd3 dolomite. Plant height, shoot dry weight, and visual quality ratings were determined six weeks after potting. Media composed of 100% cotton gin trash produced plants with significantly less height and shoot dry weight. Height inhibition was apparent by 3 weeks after potting. Coleus grown in media composed of 60-1002 pine bark had higher visual quality ratings than those grown in media having cotton gin trash as the primary constituent.
EFFECTS OF SEED SIZE ON LIMA BEAN GROWTH AND DEVELOPMENT
Authors: Wyatt Jim E. , Akridge Marla C.
Published: February 2019

Objectives of this study were to determine the effects of lima bean seed size differences and a short chilling period after planting on seedling emergence rate, seedling abnormalities and vigor. Individual seeds of 'Jackson Wonder' lima bean were weighed and placed into one of five size classes: 24-33. 36-41. 44-49, 52-57, and 60-73 g per 100 seed. Seed of each size class were germinated at a constant 23-26C or chilled at 8C for 24 hrs and then moved to 23-26C conditions for the remainder of the study. A 24 hr chilling period after planting had a detrimental effect on subsequent lima bean seedling emergence only from 8 through 11 days after planting. Plant fresh and dry weights were significantly less for the chilled seed treatment. Temperature treatments had no effect on percent normal and abnormal seedlings or primary leaf area. No differences in seedling emergence number or rate were found among seed size classes. Smaller seedclasses had significantly fewer normal and more abnormal seedlings than larger seed size classes. The largest seed class produced seedlings with about two times more fresh and dry weights and leaf area than those from the smallest seed weight class. Plant fresh and dry weights and leaf areas from all seed size classes were significantly different from each other.
MUSCADINE GERMPLASM EVALUATION IN THE GULF SOUTH
Authors: Gupton Creighton , Smith Barbara
Published: February 2019

Twenty-two muscadine (Vitis rotundifolia) cultivars wars planted in a 4-replication randomized complete block design to 1) accumulate elite germplasm 2) evaluate germplasm and catalog traits that are potentially useful in breeding programs for improving quality and reducing diseases of muscadines consumed as wine, unfermented products, or fresh fruit, and 3) identify cultivars that have acceptable fresh fruit quality. Harvest date ranged from 25 August 92 for 'Southland,' 'Sugargate,' and 'Summit' to 17 September 92 for 'Doreen,' and 'Watergate'. 'Magnolia,' 'Doreen,' 'Janebell,' 'Higgins,' 'Carlos,' and *Welder' produced the highest yields and 'Sugargate,' 'Black Beauty,' 'Fry Seedless,' 'Jumbo,' and 'Sweet Jenny' were the lowest yielding cultivars. The largest berries were produced by 'Black Beauty,' 'Sweet Jenny,' 'Sugargate,' 'Supreme,' and 'Jumbo'. 'Fry Seedless,' 'Nobel,' 'Welder,' 'Doreen,' 'Hunt,' 'Southland,' and 'Sterling' produced the smallest berries. Virtually no ripe rot was found on any cultivar. 'Doreen,' Fry Seedless,' 'Nobel,' 'Supreme,' and 'Welder' were practically free of all disease. The most promising fresh fruit cultivars were 'Supreme,' 'Sweet Jenny,' and 'Black Beauty'.
YIELD AND QUALITY EVALUATION OF SEVEN STRAWBERRY CULTIVARS IN EASTERN OKLAHOMA
Authors: Chrz D.R. , Maness N.O. , Wahem I.
Published: February 2019

Seven different quality attributes were assessed during the early, middle and late phases of harvest for years 1990-1992: marketable berry yield, berry weight, berry firmness, berry color (tri stimulus chromameter “a” value), percent soluble solids, percent titratable acidity (percent cinic acid) and the ratio between soluble solids and titratable acidity. Marketable berry yield was influenced by harvest year, harvest season and cultivar. Berry weight varied substantially between cultivars and between seasons. Berry color remained stable through the harvest seasons with slight differences in color between cultivars. Berry firmness differences were generally associated with cultivar and varied little through the harvest seasons. Berry flavor (indicated by the ratio between soluble solids and acidity) tended to remain stable through the harvest seasons with considerable differences between cultivars. Work was supported by USDA grant 90-34150-5022 and the Oklahoma Agricultural Experiment Station.
Fungi Associated with Spring Dead Spot Reduces Freezing Resistance in Bermudagrass
Authors: Nus J.L. , Shashikumar K.
Published: February 2019

Although the effect of cold winters on the severity of bermudagrass (Cynodon dactylon Pers.) spring dead spot (SDS) has been studied, information is needed concerning the effect of infection by fungi associated with SDS on the host's freezing resistance. A-22 bermudagrass was inoculated with Leptosphaeria korrae J. Walker & A.M. Smith and Ophiospharella herpotricha (Fr.) J. Walker & A.M Smith. Differential thermal analysis was used to monitor exotherm temperatures of healthy and O. herpotricha- and L. korrae-infected A-22 bermudagrass at 10-day intervals during 90 days of acclimation in cold chambers. Healthy bermudagrass crowns supercooled to an average of -6.7C and fungi-infected crowns supercooled to an average of -4.8 and -4.4C, respectively. Healthy crown exotherm temperatures were significantly lower than those of fungi-infected bermudagrass crowns on all nine sampling dates. This result indicates that fungi-infected plants are more susceptible to cold damage.
Epicuticular Wax Morphology and Composition are Related to Grapefruit Chilling Injury
Authors: McDonald Roy E. , Nordby Harold E. , McCollum T. Gregory
Published: February 2019

Differences in chilling injury (CI) susceptibility between `Marsh' grapefruit (Citrus paradisi Macf.) from interior and exterior tree canopy positions were analyzed to investigate the hypothesis that epicuticular wax morphology and composition influence CI development during low-temperature storage. The sun-exposed surface of fruit from the exterior canopy had significantly more CI and larger wax platelets than the shaded surface of the same fruit. Interior canopy fruit had significantly less CI and smaller wax platelets than exterior canopy fruit. Hydrocarbons, primarily n-alkanes, were significantly more abundant in the epicuticular wax on the surfaces of sun-exposed and exterior fruit compared with surfaces of shaded and interior fruit, respectively. Results of this study suggest that epicuticular wax plays a role in the development of external CI symptoms on grapefruit.
Postharvest Leaf Blackening and Preharvest Carbohydrate Status in Three Protea Species
Authors: McConchie Robyn , Lang N. Suzanne
Published: February 2019

Protea neriifolia R. Br., P. susannae E.P. Phillips × compacta R. Br., and P. eximia (Salis. ex Knight) Fourcade cut flower stems were examined to determine the relationship between postharvest leaf blackening rate and preharvest carbohydrate status. Postharvest leaf blackening was highest (83% by day 4) in P. eximia floral stems, which had the lowest preharvest sucrose concentrations. In contrast, P. susannae × compacta had <5% leaf blackening by day 4 and the highest preharvest leaf sucrose concentrations. Starch concentrations were highest in P. neriifolia; however, leaf blackening was intermediate between P. susannae × compacta and P. eximia and reached 52% at day 4. Preharvest carbon-exchange rate and stomatal conductance in all three species were extremely low, despite high photosynthetically active radiation and apparent lack of water stress. Comparing preharvest carbohydrate profiles in vegetative and floral stems suggests that vegetative stems may have a sink-to-source transition zone between the second and third divisions, while most leaves on floral stems may have transferred carbohydates to source leaves at harvest. While preharvest floral stem sucrose concentrations can be linked to leaf blackening rate, the high starch reserves in P. neriifolia reduced leaf blackening little in this species. We conclude that leaf blackening may be related more to inflorescence sink demand after harvest and oxidative substrate availability than preharvest reserve carbohydrate concentrations in each species.
Studying Some Properties of Amylases Extracted from `d'Anjou' Pears
Authors: Li S.J. , Facteau T.J. , Chen P.
Published: February 2019

Several characteristics of amylases involved in starch degradation were studied in extracts from immature (30 days before harvest) `d'Anjou' pears (Pyrus communis L.). Enzyme activity was not detected until after at least 60 minutes of incubation in frozen or lyophilized tissues. Activity increased significantly after 90 minutes and increased linearly after 2 to 12 hours of incubation. Activity was greater, however, in frozen than in lyophilized tissues. Three buffers (acetate, tris-HCl, and imidazole-HCl) were used at a range of pH levels (4.6-8.2) to ascertain the optimum assay system. Highest specific activity was recorded with acetate buffer at pH 5.6. The Km value in this system was 1.43 × 10-3g·ml-1. Specific activity increased as Ca concentration in the reaction mixture increased from 1 to 15 mm CaCl2 but did not change as Ca concentration increased from 15 to 25 mm CaCl2. The `d'Anjou' pear amylases were purified 5.7-fold using ammonium sulfate fractionation.
Field Tests for Cucumber Resistance to Gummy Stem Blight in North Carolina
Authors: Wehner Todd C. , St. Amand Paul C.
Published: February 2019

Gummy stem blight [Didymella bryoniae (Auersw.) Rehm] is the second most important pathogen of field-grown cucumbers (Cucumis sativus L.) in North Carolina and a severe problem for greenhouse-grown cucumbers worldwide. To determine whether resistance exists under North Carolina field conditions, 83 cultigens [cultivars, breeding lines, and plant introduction (PI) accessions] were evaluated in the field for 4 years for their resistance to a mixture of D. bryoniae isolates. Plants were inoculated at the vine tip-over stage and rated for foliar lesion size and number. Cultigens identified as resistant in Wisconsin and The Netherlands were not resistant in North Carolina. When averaged over years and locations, the most resistant C. sativus cultigens were PI 164433, `Slice', PI 390264, M 17, and M 12. Several accessions of related Cucumis species were highly resistant: PI 299568 (C. myriocarpus Naud.), PI 282450 (C. zeyheri Sond.), PI 299572 (C. myriocarpus), and PI 233646 (C. anguria L.). The most susceptible cultivars were `Colet', `Meresto', `Supergreen', `Dura', `Pioneer', `Marketmore 76', `Pickmore', and `Addis'. `Calypso' and `Dasher II', popular cultivars in North Carolina, were moderately susceptible.
Transplant Age Influences Summer Squash Growth and Yield
Authors: NeSmith D.S.
Published: February 2019

Greenhouse and field experiments were conducted to determine the influence of transplant age on growth and yield of `Dixie' and `Senator' summer squash (Cucurbita pepo L.). Dry weight and leaf area measurements indicated that 28- to 35-day-old greenhouse-grown transplants grew more slowly after transplanting than plants that were 10, 14, or 21 days old. Older transplants flowered earlier; however, earlier flowering did not result in higher early yields. Transplants of varying ages did not differ greatly in yield and yield components in the field, although all transplants had higher early yields than the directly seeded controls. Results from these experiments suggest that 21 days may be a reasonable target age for transplanting summer squash. If transplanting were delayed by adverse planting conditions, 21-day-old transplants would likely have at least a 10-day window of flexibility before yields would be reduced notably by additional aging.