bluuebunny/crossref_metadata_2025 huggingface dataset:
ADAPTABILITY OF ASIAN PEARS TO SOUTH CAROLINA'S SANDHILLS REGION
Authors: Reighard Gregory L. , Guinn Terry
Published: February 2019

An Asian pcar variety trial planted in 1989 near Columbia, South Carolina was evaluated for growth, productivity, and disease resistance for 4 years. A total of 13 cultivars were observed. The Chinese types Ya Li and Shin Li reached full bloom in mid-March 2 weeks before the Japanese types. The latest blooming cultivars were Choju and Twentieth Century. Shinsei, Shin Li, and Ya Li were the most vigorous cultivars, whereas Niitaka, Shinko, and Shinsui were the least vigorous. Most cultivars produced suckers on the Betulaefolia rootstock; however, few suckers were observed for Chojuro, Shinseiki, Shinko, and Ya Li. Fruit production began in the third year, and after the fourth year Shinseiki, Twentieth Century, Choju, Shinko, and Kosui were the most productive cultivars (8.1-18.2 kg/tree). Chinese types were not precocious but did produce the largest fruit (203-270 g). Choju ripened the earliest (early July), and the Chinese types ripened the latest (late August). Fireblight had infected few trees after 4 years and still was not a problem at this location.
PEACH ROOTSTOCK PERFORMANCE IN ARKANSAS
Authors: Bourne Robert D. , Rom Curt
Published: February 2019

Several trials were conducted to compare standard and potential peach rootstocks. The NC-140 trial, with 'Redhaven' as the scion, included 'Halford', 'Siberian-C', 'Bailey', 'GF-677', 'GF-655.2', 'Damas', 'Citation', 'Lovell' and 'GF-43' rootstocks. All trees with 'Citation' as the rootstock died in the first three years. while 'CF-43' and 'Siberian-C' had low survivability and productivity. 'Damas' and 'GF-43' suckered profusely. 'Lovell' trees bloomed an average of one-to-three days later than all other entries. 'Halford'. 'GF-677', 'Bailey' and 'Lovell' had the highest yields. A trial comparing 'Loring' own-root and on 'Tennessee Natural' resulted in similar yields among stocks, but larger fruit and tree size with the own-root trees. 'Redskin' own-root and on 'Lovell' also resulted in similar yields among stocks, and larger tree and fruit size with own-root trees. A trial using the processing peach selection A-219 as the scion on `S-37' 'Chum Li Tao', AR-78118, 'Yarbrough Cling' and 'Lovell' resulted in highest yields and yield efficiency with 'Yarbrough Cling', 'Lovell' and 'S-37' rootstocks.
ROOTSTOCK AFFECTS TREE GROWTH AND PRUNING REQUIREMENT
Authors: Rom Curt R.
Published: February 2019

As part of the NC-140 rootstock evaluation trials, `Starkspur Supreme Delicious' on 18 rootstocks planted in 1984 were evaluated for growth and pruning requirement. After 9 seasons, trees on the P.22 produced the smallest trees, 1.1 m width and 1.7 m height. The stocks P.16, P.2 and Bud.9 produced trees 2.0-2.2 m wide and 2.1-2.6 m tall. Trees on MAC.39, C.6, MAC 1, M.26 EMLA P.1, BUD.490, M.7 EMLA, CG.24, and domestic seedling were 2.9-3.4 m wide and 3.7-4.3 m tall. The largest trees were on P.18 and M.4; 3.6 m wide and 4.2 m tall. Dormant pruning time in two seasons significantly increased at an exponential rate with increasing tree width and height. An asymptote for maximum pruning time had an x-axis intersection at approximately 2.7 m tree height. Pruning time per tree significantly increased in a linear manner with increasing trunk cross section. When pruning time was calculated on a per hectare basis, trees planted at 1460 to 2000 trees/ha required less pruning time than when planted at ≤ 750 tr/ha or ≥ 4000 tr/ha. Trees on P.16, P.2, Bud.9 and C.6 required the least pruning per unit of fruit production.
ECONOMIC ANALYSIS OF DIFFERENT HARVEST METHODS FOR FRESH MARKET COLLARD GREENS
Authors: Teague Paul W. , Teague Tina Gray
Published: February 2019

spring field trials conducted over 2 years were used to determine differences in net returns using “cut” (harvested by removing the whole plant near the ground level for a one time over harvest) and “shucked” collards (harvested by removing marketable sized individual leaves using multiple harvests). 'Blue Max' transplants were set 11 March 1991 and 11 Feb 1992 in rows spaced 25.4cm apart on raised beds spaced 1m apart. Four spacing treatments were evaluated (7.62, 15.24, 22.86, and 30.48 cm between plants) in a RCB with 4 replications. Plants were harvested beginning 25 April 1991 and 28 April 1992 once (cut) or over 5 wks (shucked). Yields were higher for shucked collards spaced 15.24cm in both years, but no differences Were observed in cut collards. cut collards provided a higher 1st harvest yield. A system analysis to provide 1000 boxes (9.lkg) of collards/wk was imposed to determine the economics of harvest method. Cost differences Were considered to reflect differences in hectareage required, transplant cost for 4 densities, and a 25% higher harvest cost/box for shucked collards. The shuck harvest method provided an economic advantage over cutting of $9853 and $1671 in 1991 and 1992, respectively, where all production was assumed to come from transplanted collards. when a combination of transplanting and direct seeding was assumed, results indicate an economic advantage to cutting of $680 for the system using 1992 yield data.
EFFECTS OF BROCCOLI-CROPPED SOIL ON THE GROWTH OF BROCCOLI, CABBAGE, AND CAULIFLOWER
Authors: Santos Jose Reynaldo A. , Leskovar Daniel I.
Published: February 2019

Broccoli, cabbage, and cauliflower were grown in the greenhouse on fallowed soil (FS) or on soil previously cropped with broccoli CBS) for three years. Fertilization levels (kg/ha) were none, 67N-22P, and 135N-44P. Inhibition of root and shoot growth components, and leaf color was evaluated at 30, 44, 58, and 72 days after seeding. Shoot and root growth of cauliflower, grown on BS, progressively declined over time, while that of broccoli and cabbage either increased or remained unaffected. Application of fertilizer (67N-22P) improved the shoot growth of cabbage but did not alleviate the symptoms associated with allelopathy, i.e., stunted growth, leaf chlorosis, reduced leaf area, observed in cauliflower. Whole plant extract of broccoli decreased percent germination of cauliflower, and reduced the speed of germination of all three test crops in the order of cauliflower>broccoli>cabbage.
THE EFFECT OF SPACING ON FRUIT LOAD DISTRIBUTION ON GREENHOUSE TOMATOES
Authors: Mullinix Benjamin G. , Phatak Sharad C. , Cooper Janet
Published: February 2019

Ten tomato cultivars (fresh market) were grown in a greenhouse using 30 cm or 45 cm in-row spacing with rows spaced 60 cm apart in 1979 from January through June. The cultivars were Big-O, Bigset, Hotset, Monte Carlo, Petra, Stella, Supal, Tropic, Wilters Villmarie, and WW200. Cultivars producing high number of fruit had lower fruit weight. Seven cultivars produced more fruit under the 30 cm spacing. Six cultivars produced slightly heavier fruit at 45 cm spacing and five cultivars produced larger class sized fruit at 45 cm spacing. Five cultivars had fruit by cluster distribution significantly higher up the plant at 45 cm spacing, while two were significantly lower. Three cultivars had greater production later in the growing period at 45 cm spacing, while two were greater at the beginning.
EVALUATION OF CLOMAZONE FOR USE IN CUCURBITS
Authors: Porter Wayne C.
Published: February 2019

Clomazone was evaluated for reemergence weed control in summer squash, watermelon, cantaloupe, cucumber, and pumpkin. Clomazone was applied preplant incorporated or surface-applied after planting. All crops exhibited varying degrees of chlorosis in the cotyledonary stage and first one to three true leaves. Cucurbit tolerance to clomazone was pumpkin = squash > cucumber > watermelon > cantaloupe. Method of application did not affect crop vigor. Some pumpkin cultivars were more tolerant than others. Clomazone controlled Brachiaria platyphylla and Portulaca oleracea with both methods of application. Surface application provided better control of Amaranthus hybridus and A. spinosa. Mollugo verticillata was not controlled. Preplant incorporated application of clomazone tended to reduce the yield of watermelon.
USE OF RANDOM AMPLIFIED POLYMORPHIC DNA (RAPD) TO IDENTIFY SHORT-DAY GRANO-TYPE ONION CULTIVARS
Authors: Roxas Virginia P. , Peffley Ellen B.
Published: February 2019

Nineteen random primers yielded 36 PCR-amplified products of Allium cepa profiles of each of 15 short-day grano-type onionsgrown commercially in Texas and Southern United States were compared. Several PCR productswere unique among the cultivars and can be used to differentiate among the onion cultivars investigated. A phenogram of the cultivars based on the co-occurrences of the PCR products was derived.
Copper Hydroxide Controls Root Distribution In Container-Grown Carpentaria Palm
Authors: Svenson Sven E. , Broschat Timothy K.
Published: February 2019

The influence of copper hydroxide [Cu(OH)2] application to interior container surfaces on root growth at the container-medium interface was studied using Carpentaria palm [Carpentaria acuminata (H. Wendl. & Drude) Becc.]. Cu(OH)2 (0, 100, 200, or 400 g) was mixed with one liter of either white latex house paint, or NuFilm-17 surfactant, and applied to all surfaces inside 0.5 liter containers. Plants were grown in untreated containers, in containers treated with paint or NuFilm-17 only, or in containers treated with Cu(OH)2 in paint (100 g rate only) or NuFilm-17 (100, 200 or 400 g per liter). When applied in paint or NuFilm-17, Cu(OH)2 reduced root growth at the container-medium interface, controlling the circular growth pattern commonly observed in container-grown plants. Controlling circling root growth at the soil-container interface did not influence shoot or root dry weight, but did reduce total root length. Application of Cu(OH)2 with paint was unsightly, while application with NuFilm-17 was almost unnoticeable.
FOUR ORNAMENTALS RELEASED FROM ARKANSAS PEACH BREEDING PROGRAM
Authors: Moore James N. , Rom Roy C. , Brown Stanley A. , Klingaman Gerald L.
Published: February 2019

Three ornamental peaches and one ornamental nectarine were released in 1992 from the Arkansas peach breeding program. `Tom Thumb' is a red-leaf dwarf peach with attractive foliage that is retained throughout summer. `Leprechaun' is a green-leaf dwarf nectarine with small but attractive, freestone fruits. `Crimson Cascade' and `Pink Cascade' are red-leaf peaches with trees of standard size that exhibit a weeping growth habit. `Crimson Cascade' produces double flowers that are dark red while `Pink Cascade' double flowers are pink. The attractive plants of these cultivars should be of value in home landscapes.
CAD/GIS AS A TOOL IN NATIVE PLANT SPECIES CONSERVATION
Authors: Creech D.L. , McDonald D.
Published: February 2019

Texas is botanically diverse with approximately 5500 native plants identified: east Texas contains about 40% of the total. While most species are stable, many are classified as rare, threatened, vulnerable, or endangered. Databases for east Texas plant communities and vegetative analyses are numerous. However, they are not yet integrated into easy-to-sort-and-query computer files. Computer-Assisted Drafting (CAD) and Geographic Information Systems (GIS) technology offers powerful applications to the storage, management, and spatial analysis of species inventories, plant community dynamics, and long-term habitat monitoring. At SFASU, the College of Forestry's GIS Center is being utilized to develop comprehensive east Texas resource inventories on a ten-station HP Apollo/ArcInfo platform. In the horticulture program, a twenty-station PC/AutoCad teaching laboratory is being used to create layered maps of the SFASU Arboretum, the on-campus landscape and off-campus plant communities. The integration of CAD and GIS projects through a DXF format takes advantage of the attributes of both technologies.
INFLUENCE OF PESTICIDES ON NITROGEN CONTENT OF TOMATO PLANT S
Authors: Sasseville David N.
Published: February 2019

Tomato plants were grown in a greenhouse in a sand:soil mixture with six pesticide treatments applied weekly at 1 mg a.i./kg soil mixture as a soil drench. Plants were grown for six weeks with nitrogen applied weekly at 80 mg per plant as calcium nitrate. Glyphosate (Roundup) was toxic to plants with reduced dry weight of all tissues, but greater nitrate concentration in the leaf and root tissues. Captan produced the greatest dry weight, with mot tissues dry weights significantly greater than the control treatment. Captan resulted in significantly higher nitrate content in the tissues, but there was no difference between captan and the control on total N content. Both nitrapyrin (N-Serve) and sethoxydim (Poast) had significantly less growth and total N content than the control, as well as higher nitrate content in the growing medium. It appears that these two chemicals may inhibit nitrate uptake or cause other phytotoxic effects The other chemicals metalaxyl (Subdue) and etridiazole (Terrazole) had intermediate responses. While they both had reduced growth and total N content, these were not significantly different from the control treatment. Etridiazole had reduced nitrate content, but metalaxyl nitrate content was significantly greater than the control and comparable to captan, primarily because of high nitrate content in the leaves.
MORPHOLOGY AND YIELD OF PAPRIKA PEPPER IN RESPONSE TO METHOD OF STAND ESTABLISHMENT
Authors: Kahn Brian A. , Cooksey James R. , Motes James E.
Published: February 2019

Raw seed, primed seed, and transplants were compared for effects on stand establishment, plant morphology, and yield of paprika pepper (Capsicum annuum L.) Raw seed seemed satisfactory for stand establishment, although primed seed had the potential to provide better initial stands. When populations were equalized, there were few differences in plant growth, plant morphology, or fruit yield attributed to seed treatment. Morphology of plants established by direct seeding generally was favorable for mechanical harvest. Use of transplants did not result in higher marketable fruit yields than direct seeding in two out of three years. When compared to plants established by direct seeding, three trends were consistent across all three years for plants established by transplanting: a) they were more massive: b) they had larger vertical fruiting planes: and c) they had more branches. These traits would increase the difficulty of mechanical harvest and would create the potential for more trash in the harvested product. Thus, transplanting is not recommended for stand establishment of paprika intended for mechanical harvest.
EFFECTS OF ROW COVERS ON YIELD OF WHITE POTATOES IN MISSOURI
Authors: Wilson Mack A. , Khan Victor A. , Stevens Clauzell
Published: February 2019

Four types of row covers were evaluated on two cultivars of potatoes (`Atlantic' and Frito-Lay 795') at Charleston, Missouri on sandv loam entisol. Row covers used were spunbonded polyester, clear and white slitted and VisPore. Significant interactions occurred in the sub-plot (row cover × varieties) and sub-subplots (varieties × flower treatments) for numbers of grade A potatoes. The total numbers of potatoes for 'Atlantic' and 'Frito-Lay 795' cultivars as influenced by flower removal and row cover treatments showed significant interactions of row covers × varieties and varieties × flower treatments. Yield of grade A potatoes for both cultivars as influenced by flower removal and row cover treatments showed a significant interaction between row covers × varieties. Genetic differences occurred among potato cultivars in response to flower removal. cultivar response to row covers were also different based on genetic makeup. Clear and spunbonded polyester were superior to other types of row covers for grade A numbers and yield of potatoes.
Herbicides for Container-grown Rain Forest Species
Authors: Sharman K.V.
Published: February 2019

Four granular formulations of preemergence herbicides-oxadiazon, oxadiazon in combination with simazine, dichlobenil, and oxyfluorfen + oryzalin-were evaluated for weed control and phytotoxic effects on 10 species of container-grown Australian rain forest plants. Herbicides were applied at half and at one and two times the manufacturer's recommended rate. Oxyfluorfen + oryzalin, oxadiazon, and oxadiazon + simazine controlled all weed species at half the recommended rates (1.0 + 0.5, 2.0, and 2.0 + 0.5 kg·ha-1, respectively) with no phytotoxic effects after 10 weeks to nine of the 10 rain forest species tested: broad-leafed lilly-pilly [Acmena hemilampra (F. Muell. ex Bailey) Merr. and Perry], red ash [Alphitonia excelsa (Cunn. ex Fenzl) Reisseck ex Benth.], rusty bean [Dysoxylum rufum (A. Rich.) Benth.], macaranga [Macaranga tanarius (L.) Muell. Arg.], fibrous satinash [Syzygium fibrosum (Bailey) T. Hartley and Perry], Queensland golden myrtle [Metrosideros queenslandica L.S. Smith], cluster fig [Ficus racemosa L.], corduroy tamarind [Arytera lautereriana (Bailey) Radlk.], and celerywood [Polyscias elegans (F. Muell and C. Moore) Harms]. Dichlobenil depressed plant growth of red ash and failed to control bittercress (Cardamine hirsuta L.) and green amaranth (Amaranthus viridus L.), even at twice the recommended rate (4.0 kg·ha-1). All herbicides applied at half the recommended rates produced minor to moderate plant injury within 5 weeks of the first application to corduroy tamarind and northern silky oak [Cardwellia sublimis F. Muell.]. A second application 10 weeks after the first caused no significant plant injury to corduroy tamarind but resulted in severe plant injury to northern silky oak. This finding validates the previously reported sensitivity of Proteaceous spp. to preemergence herbicides. Chemical names used: (2-tert-butyl-4-(2,4-dichloro-5-isopropoxyphenyl)-Δ2-1,3,4 oxadiazoline-5-one) (oxadiazon); (2-chloro-4,6-bisethylamino-1,3,5-triazine) (simazine); 2,6-dichlorobenzonitrile (dichlobenil); 2-chloro-1-(3-ethoxy-4-nitrophenoxy)-4-(trifluoromethyl)benzene (oxyfluorfen); and 3,5-dinitro-N4,N4 -dipropylsulfanilamide (oryzalin).
Response of Caterpillar Pests and the Parasite Diadegma insulare to Collard Cultivars and a Pyrethrin Insecticide
Authors: Schalk J. M. , Shepard B.M. , Stoner K.A.
Published: February 2019

There were no differences in mortality, plant preference, or plant damage when diamondback moth (DBM) (Plutella xylostella L.) larvae were tested in no-choice and free-choice tests using leaf disks of resistant (`Green Glaze') or susceptible (`Vates', standard commercial cultivar) collards (Brassica oleracea Acephala group). No residuals of the pyrethrin insecticide Asana-XL (esfenvalerate) were detected 6 days after its application when DBM larvae were exposed to excised foliage for 72 hours. In a field test, more imported cabbage worm (ICW) (Pieris rapae L.) eggs were found on `Vates' treated with the insecticide than on nontreated Vates' or nontreated or treated `Green Glaze'. The fewest ICW, cabbage looper (CL) (Trichoplusia ni Hubner), and DBM larvae were found on the insecticide-treated cultivars. Fewer caterpillars were found on `Green Glaze' than Yates'. An additive effect of plant resistance and insecticide application lowered counts of DBM, ICW, and CL larvae. Percent parasitism of DBM by Diadegma insulare Cresson (Hymenoptera: Ichneumonidae) was lower on cultivars treated with the insecticide. Field plant damage ratings were higher for nontreated `Vates' and lowest for treated cultivars, but nontreated `Green Glaze' had a significantly lower feeding damage rating than nontreated `Vates'. Chemical name used: (S)-cyano (3-phenoxy phenyl) methyl-(S)-4 chloro-alpha (1-methylethyl) benzeneacetate [esfenvalerate (Asana-XL)].
Estimating Transpiration for Three Woody Ornamental Tree Species using Stem-flow Gauges and Lysimetry
Authors: Devitt D.A. , Berkowitz M. , Schulte P.J. , Morris R.L.
Published: February 2019

We compared transpiration estimates of three common desert landscape tree species using stem-flow gauges and lysimetry. Argentine mesquite (Prosopis alba Grisebach), desert willow [Chilopsis linearis (cav.) Sweet var. linearis], and southern live oak (Quercus virginiana Mill., seedling selection) were subjected to three irrigation regimes. Leaching fractions of +0.25, 0.00, and -0.25 were imposed for 2 years. During the summer of the second year, we conducted a comparative transpiration study. Trees growing in 190-liter plastic containers had a highly linear correlation (r = 0.98, P = 0.001) between transpiration estimated by stem-flow gauges and lysimetry. An average 18% error was measured between paired data (total runs of 14 to 72.5 hours) of stem-flow gauge and lysimetry transpiration estimates. However, a lower error was correlated significantly with longer run times (r = -0.37, P = 0.05). Based on field measurements taken in this experiment, run times would have to be >68 hours to maintain an associated error below 10%. Higher cumulative transpiration also was associated with longer run times (r = 0.80, P = 0.001). These results suggest that the stem-flow gauge can be used to estimate transpiration accurately to schedule irrigation for woody ornamental trees in an arid environment, provided that irrigation predictions are not based on short-term stem-flow gauge estimates (<68 hours).
Regeneration of Bigleaf Magnolia by Somatic Embryogenesis
Authors: Merkle S.A. , Watson-Pauley B.A.
Published: February 2019

Bigleaf magnolia (Magnolia macrophylla Michx.) cultures were initiated from immature seeds on an induction medium containing 9.0 μm 2,4-D, 1.1μm BA, and 1 g casein hydrolysate/liter. After 2 months on induction medium, one culture produced adventive embryos. Clumps of embryos transferred to liquid induction medium proliferated as nodules, which grew in diameter, but failed to produce embryos while maintained in induction medium. Nodules transferred to basal medium produced clumps of somatic embryos, which continued to produce repetitive embryos with monthly transfer to fresh basal medium. Individual embryos transferred to basal medium lacking casein hydrolysate germinated and leaves expanded. Plantlets derived from these embryos were transferred to potting mix and acclimatized to greenhouse conditions. Chemical names used: (2,4-dichlorophenoxy)acetic acid (2,4-D); N -(phenylmethyl)-lH-purin-6-amine (BA).
Revising the Classification of Cultivated Centrosema and Clitoris in the United States
Authors: Fantz Paul R.
Published: February 2019

Revised treatments of the genera Centrosema (DC.) Benth. (Leguminosae: Fabaceae) and Clitoris L. follow the style used in Hortus Third. Inventory of species, nomenclature, authorities, morphological descriptions, and distributions have been updated.
Calcium and Phosphorus Influence Creeping Bentgrass and Annual Bluegrass Growth in Acidic Soils
Authors: Kuo S.
Published: February 2019

Acidifying soil to prevent annual bluegrass (Poa annua L.) from infesting creeping bentgrass (Agrostis palustris Hud.) reduces soil P and Ca availability. This study examined Ca and P effects on the growth of these two grasses in four moderately acidic soils using CaSO4 as a Ca source. Each soil received four P rates (0, 10, 40, or 80 mg·kg-1) and three Ca (as CaSO4) rates (0, 400, or 800 mg·kg-1). Neither Ca nor P treatments substantially changed pH or exchangeable soil Al. Clipping yields, tissue P concentration, and P uptake of both grasses were affected by soil NaHCO3-P levels. Compared to bentgrass, annual bluegrass had higher clipping yields and P uptake at high P rates or high NaHCO3-P levels; this result indicates that annual bluegrass was as acid-tolerant as the bentgrass, provided that available P in the soil is adequate. Adding CaSO4 to the Papac soil, which contained the least amount of exchangeable Ca among the four soils, markedly enhanced the clipping tissue P concentration and P uptake of creeping bentgrass but not those of annual bluegrass; this result indicates that a differential response to Ca existed between the two grasses. Maintaining an adequate soil Ca availability was necessary to improve bentgrass growth, particularly for the acid soil containing low available Ca initially.
Lychee Pericarp Browning Caused by Heat Injury
Authors: Underhill S.J.R. , Critchley C.
Published: February 2019

Mature lychee (Litchi chinensis Sonn.) fruit were heat-treated at 60C for 10 min to study heat-induced pericarp browning. Polyphenol oxidase (EC 1.10.3.2) activity of the pericarp increased immediately, corresponding with rapid anthocyanin degradation, Tissue browning was observed 2 min after heating, with pigmentation distributed uniformly throughout the pericarp. The distribution of brown pigments was different than the highly localized browning observed under ambient desiccation. Although both ambient and heat-induced pericarp browning are visually similar, the anatomical distribution of brown pigmentation is quite distinct. The distribution of brown pigmentation was not consistent with anthocyanin localization. Following ambient desiccation, the mesocarp became colorless even though this represented the greatest concentration of pigment. Browning caused by heating may result from nonselective degradation of a range of compounds, including anthocyanin.
Constructing an Inexpensive Three-channel Reversible Peristaltic Pump
Authors: Tisserat Brent , Galletta Paul
Published: February 2019

Plans are presented for the construction of a three-channel reversible peristaltic pump that can operate at a rate of 45 ml/minute per channel. The cost of this peristaltic pump is about $84 compared to $620 for a commercially available peristaltic pump of similar design and capability. An electronic control scheme for pump operation is presented also.
Plant Population Influence on Squash Yield, Sweetpotato Whitefly, Squash Silverleaf, and Zucchini Yellow Mosaic
Authors: Powell Charles A. , Stoffella Peter J. , Paris Harry S.
Published: February 2019

Zucchini squash (Cucurbita pepo L.) fruit yield and the incidence of sweetpotato whitefly (SPWF) [Bemisia tabaci (Gennadius)], squash silver leaf (SSL) disorder, and zucchini yellow mosaic virus (ZYMV) were measured during Spring and Fall 1991 in experiments containing various plant populations. In both experiments, as the within-row spacing increased from 30.5 to 76.2 cm or the number of plants per hill decreased from three to one, the number of marketable fruit per hectare decreased, and the marketable fruit per plant increased. Adult SPWF populations increased with decreased within-row spacing in the spring but not the fall experiment. The incidence of SSL or ZYMV infection was not affected by plant population in either experiment. The results indicate that increasing zucchini squash plant population can increase yield without affecting the incidence of SSL or ZYMV.
Temperature and Humidity Affect Pillowy Fruit Disorder in Cucumber
Authors: Staub Jack E. , Navazio John P.
Published: February 2019

A study was designed to determine whether temperature alone or temperature and relative humidity (RH) interactions affect the development of pillowy fruit disorder (PFD) in cucumber (Cucumis sativus L.). Fruit of `Calypso', `Flurry', `Carolina'? and inbred breeding line 39 were matured in four environments: cyclic and high (22 to 45C) and moderate (22 to 30C) temperatures at two RHs (35% and 75%). PFD symptoms were most severe at high temperature and RH; thus, both contribute to the development of this disorder. Line 39 had the highest PFD ratings, regardless of growing environment, a result indicating that cultigens respond differently to these imposed stresses.
Cleaning Method Affects Shrinkage Rate of Citrus Fruit
Authors: Hagenmaier Robert D. , Baker Robert A.
Published: February 2019

The shrinkage rate of `Marsh' grapefruit (Citrus paradisi Macf.), `Ambersweet' hybrid [(C. reticulata Blanco × C. paradisi Macf. × C. reticulata) × C. sinensis (L.) Osb.] and `Valencia' oranges [C. sinensis (L.) Osb.] was increased 50 % to 150% by washing the fruit with rotary brushes, but was not changed by hand-washing the fruit with cellulose sponges. Internal CO2 increased using both washing methods. Waxed fruit obtained from five Florida packinghouses and cleaned with rotary brushes and waxed had shrinkage rates the same as those of nonwashed controls. Thus, controlling the washing process is important to minimize shrinkage of fresh citrus fruit.
Testing the Morphological Aspects of Polyethylene Glycol-primed Tomato Seeds with Proportional Odds Analysis
Authors: Liptay A. , Zariffa N.
Published: February 2019

Priming tomato (Lycopersicon esculentum Mill) seeds in aerated -0.5 MPa polyethylene glycol (PEG) enhanced the emergence rate and the extent and percentage of embryo radicles protruding partially or completely through the seed endosperm. The radicles' growth, however, was arrested at the seedcoat. The time course of radicle protrusion through the endosperm of seeds in PEG for the first 24 hours paralleled that of seeds germinating in aerated water; however, radicle protrusion continued through the seedcoats of seeds germinating in water. The radicle of the high-vigor PI-341988 tomato line protruded more rapidly through the endosperm than that of the low-vigor ST-24 line.
Night Temperature, Photosynthetic Photon Flux, and Long Days Affect Gypsophila paniculata Flowering
Authors: Hicklenton Peter R. , Newman Suzie M. , Davies Lindsay J.
Published: February 2019

The effects of night temperature (NT) and photosynthetic photon flux (PPF) on time to flower and flower yield in `Bristol Fairy' and `Bridal Veil' Gypsophila paniculata L. (perennial baby's breath) were studied in controlled environments. Plants were grown with nights at 8, 12, 16, and 20C and 450 or 710 μmol·s-1·m-2 photosynthetic photon flux (PPF). Days were at 20C. In both cultivars, the times from the start of treatments to visible bud and from visible bud to anthesis were delayed at the lower PPF and at an NT <20C. The delays in `Bristol Fairy' were greater than those in `Bridal Veil'. Failure of `Bristol Fairy' plants to reach anthesis was common at SC NT and either 450 or 710 μmol·s-1·m-2 PPF; whereas in `Bridal Veil', nearly all plants flowered, regardless of environmental conditions. Flower yield (measured as fresh weight of inflorescences) decreased with NT in `Bristol Fairy' but was highest at 8 or 12C in `Bridal Veil'. In a second experiment using the same cultivars, the effect of curtailing long-day (LD) conditions at various stages on stem elongation and flower yield was investigated. `Bristol Fairy' required more LD cycles (>56) than `Bridal Veil' for maximum stem elongation and flower yield. Terminating LD conditions before the start of inflorescence expansion resulted in lower yields and shorter plants in both cultivars.
Ornamental Pepper Growth and Fruiting Response to Uniconazole Depends on Application Time
Authors: Starman Terri Woods
Published: February 2019

This study investigated the effects of concentration and application time of uniconazole as a spray for single- or double-pinched ornamental pepper (Capsicum annuum L. `Holiday Cheer'). Concentrations from 5.0 to 15.0 mg·liter-1 gave adequate height control, except that 15.0 mg·liter-1 reduced height excessively when applied 8, but not 10, weeks after sowing. Increasing uniconazole concentration increased red fruit percentage when applied at 10, but not 8, weeks after sowing. These results indicate that the later application was beneficial and may lessen the overdosing problem associated with triazole growth regulators. Chemical name used: (E)-(S)-1-(4-chlrophenyl)-4,4-dimethyl-2-(1,2,4-triazol-1-yl)-pent-1-ene-3-oll(uniconazole).
Longevity of Rubus Seeds after Long-term Cold Storage
Authors: Clark John R. , Moore James N.
Published: February 2019

Seeds of 25 blackberry (Rubus spp.), five red raspberry (R. idaeus L.), and two black raspberry (R. occidentalis L.) populations that had been stored for 22 to 26 years were planted in the greenhouse to evaluate their germination. Germination ranged from 0% to 84% among all populations. Thorny and thorny × thornless blackberry populations had the highest average germination; most populations had >40% germination. Thornless blackberry populations ranged from 1% to 16% germination. The seeds of two of the five red raspberry populations did not germinate and none of the black raspberry seeds germinated.
Resistance to Gummy Stem Blight in Muskmelon
Authors: McGrath D.J. , Vawdrey L. , Walker I.O.
Published: February 2019

Resistance to gummy stem blight [Didymella bryoniae (Auersw.) Rehm] was evaluated in two accessions of Cucumis melo L., PI 266935 and PI 266934. Based on disease reaction scores and dry weights, PI 266934 possessed much greater resistance than PI 266935. The quality of resistance of PI 266934 was unaffected by the ranges of seedling ages and inoculum concentrations used. No melon cultivar, to our knowledge, is highly resistant to gummy stem blight in the field, and alternative sources of superior resistance are potentially useful for breeding.
Morphology and Meiotic Behavior of Three Dendrobium Amphidiploids and Their Diploid Counterparts
Authors: McConnell James , Kamemoto H.
Published: February 2019

Floral characteristics, meiotic behavior, and sporad formation were compared in three Dendrobium tetraploids (amphidiploids) and their diploid counterparts. Amphidiploid flowers were larger than those of diploids. Diploid meiotic behavior varied; mean configurations at Metaphase I ranged from 14.3 bivalents and 9.4 univalents to 18.9 bivalents and 0.2 univalents. In amphidiploids, nearly all cells had 38 bivalents. Sporad formation also varied; diploids had 36% to 70% tetrads and amphidiploids had 97% to 100% tetrads. Preferential pairing and small chromosome size may promote bivalent formation in amphidiploids.
Cold Hardiness of Dormant Buds of Grape Cultivars: Comparison of Thermal Analysis and Field Survival
Authors: Wolf Tony K. , Cook M. Kay
Published: February 2019

Thermal analysis (TA) was used to evaluate dormant bud cold hardiness of nine Vitis cultivars weekly during the 1993–94 dormant period. TA hardiness estimates were expressed as either mean low-temperature exotherm temperature (MLTE) or temperatures lethal to 10% (LT10), 50% (LT50), or 90% (LT90) of dormant bud sample. A destructive freeze on 19 Jan. 1994 presented an opportunity to compare dormant bud field survival with laboratory estimates of bud hardiness that had been derived from TA. Vineyard air temperatures of –24C caused primary bud kill that ranged from a mean of 15% with `Concord' to 100% with `Viognier'. With the exception of `Viognier' and one of two `Cabernet Sauvignon' clones, field mortality levels were accurately bracketed by TA estimates of LT10, MLTE, and LT90 values, which had been obtained in the week preceding the freeze. `Viognier' bud hardiness was overestimated by ≈1.5C, and the hardiness of `Cabernet Sauvignon clone UCD#6' was underestimated by <1C. The discrepancy with `Viognier' may have been related to prior destruction of primary buds by bud necrosis and the misinterpretation of secondary bud exotherms as due to primary buds.
Floral Development and Breeding System of Swainsona formosa (Leguminosae)
Authors: Jusaitis Manfred
Published: February 2019

Flowers of Swainsona formosa (G. Don) J. Thompson (syn. Clianthus formosus) developed through seven floral stages from buds to open flowers in 17 days. Floral stages were correlated with the sigmoidal growth pattern of the peduncle. Self-pollination was prevented in the species by the presence of a stigmatic cuticle that precluded pollen germination until ruptured, exposing the receptive surface below. Cuticular rupture occurred in nature during bird-pollination and was emulated manually by lightly rubbing a pollen-covered finger across the stigma. The species was self-compatible, and to ensure cross-fertilization when breeding, emasculation before anther dehiscence was essential.
Root Distribution following 9 Years of Root-pruning `Me1rose'/M.26 Apple Trees
Authors: Ferree David C.
Published: February 2019

`Melrose'/M.26 apple (Malus domestics Borkh.) trees were mechanically root-pruned annually for 9 years at bloom to a 25-cm depth at 80 cm from the trunk on two sides. An evaluation of the number of roots of four size categories on the exposed wall of a 1.2 x 2-m trench located 1 m from the trunk indicated that root pruning caused a reduction in all root size categories. Roots < 1 mm in diameter were reduced 20% by root pruning, while the reduction in larger roots was nearly double this amount. The effect of root pruning on root distribution was greatest in the top 30 cm of soil, parallel to the location of the root-pruning cut. Roots below 30 cm were unaffected. The number of roots in all size categories in samples taken parallel and perpendicular to the row decreased linearly with soil depth.
COLD HARDINESS OF SIX WOODY PLANTS
Authors: Duchesne Isabelle , Rioux Jacques-André
Published: February 2019

To examine injuries caused by freezing temperature, six woody plants were placed under temperatures ranging from 0 to 20C. Control plants were placed at 0 or –2C, depending on the field sampling period. Freezing tests were done three times (September, October, and November) during the fall. In 1992, six species were tested: Genista tinctoria `Lydia', Parthenocissus `Veitchii', Weigela × florida `Variegata', Spiraea japonica `Shirobana', Spiraea japonica `Coccinea', and Arctostaphylos uva-ursi. After testing, all plants were stored at –2C for the remainder of the winter. The following May, plants were repotted into containers. Effects of freezing temperatures on plant growth were recorded at the end of the following summer. Preliminary results indicate that the most sensitive species to cold temperatures were Parthenocissus `Veitchii' and Arctostaphylos uvaursi. Plants of these two species did not survive the summer. However, for the third sampling period, Parthenocissus `Veitchii' (–18C) had better cold hardiness than A. uva-ursi (–9.5C). Genista tinctoria `Lydia' appeared to have the same cold hardiness (–10C) for the three sampling periods. The last three species had shown increasing cold hardiness beginning at around –8C in September to about –18C in November.
THE DEVELOPMENT OF CLOSED GROWING SYSTEMS IN THE NETHERLANDS AS A MEANS TO REDUCE ENVIRONMENTAL POLLUTION
Authors: Voogt W.
Published: February 2019

In the Netherlands, many crops in protected cultivation changed from soil to soilless culture in recent years. The reasons for this development were problems with soil sterilization and better growth control with soilless culture, which led to considerable yield increases. However, the growing systems used, with free leachate drainage, contribute highly to pollution of the ground and surface water with minerals (N and P). To reduce this emission, closed growing systems were developed, i.e., systems with recirculating nutrient solutions. Inherent to these systems, however, were problems such as the rapid spread of pathogens in the root environment. Methods were developed for disinfestation of the nutrient solution. Salt accumulation was also a concern, the concentrations of ions in the water used for closed systems must be lower than the uptake capacity of the plants. To avoid depletion and accumulation of certain nutrients. the addition of nutrients should be adapted to the demand during the cropping period. For this purpose, nutrient solutions and guidelines for adjustments during the cropping period were developed for several crops.
Canopy Shade and Soil Mulch Affect Yield and Solar Injury of Bell Pepper
Authors: Roberts B. Warren , Anderson Jeffrey A.
Published: February 2019

Experiments were conducted from 1989 to 1991 to compare the effectiveness of various cultural techniques in reducing solar injury (SI) and increasing yield of bell pepper (Capsicum annuum var. annuum `California Wonder') in southern Oklahoma. Treatments included black plastic mulch, white plastic mulch, straw mulch, living rye, spunbonded polypropylene used as a plant canopy shade, and bare soil. Marketable yields from plots shaded with spunbonded polypropylene rowcovers were equal to or greater than those from other treatments each year. Two out of 3 years, plots with a black plastic soil mulch had marketable yields lower than those from other treatments. SI was reduced by rowcover shade.
Root Cell Volume Affects Growth of Compact-growth-habit Tomato Transplants
Authors: Kemble Joseph M. , Davis Jeanine M. , Gardner Randolph G. , Sanders Douglas C.
Published: February 2019

The influence of flat cell volume (cavity containing growing medium) on transplant growth and development of NC 13G-1, a compact-growth-habit, fresh-market tomato (Lycopersicon esculentum Mill.) breeding line, was compared to that of a normal growth habit line, NC 8288. Transplants of each line were produced in four cell volumes (3.3, 27, 37.1, and 80cm3) for 5 weeks, evaluated and then transplanted to larger containers, and grown until anthesis. During the first 5 weeks after seeding, plant dry weight did not differ between the lines; however, plant height of NC 13G-1 was ≈60% of the height of NC 8288. For both lines, number of days from sowing to anthesis decreased as root cell volumes increased. For space-efficient production of large quantities of compact-growth-habit tomato transplants, flats with root cell volumes as small as 27 and 37 cm3 can be used without greatly delaying anthesis.
Comparison of Mulches for Fresh-market Basil Production
Authors: Davis Jeanine M.
Published: February 2019

Using various mulches for small-scale, commercial basil (Ocimum basilicum L.) production was examined. Sweet basil and bush basil, on raised beds with drip irrigation, were grown on bare ground or mulched with black polyethylene, wheat straw, hardwood bark, or mixed wood chips. Bacterial soft rot (Erwinia spp.) was highest for both basils grown with wheat straw and for sweet basil grown on bare ground or with back polyethylene mulch. Both basils grown with hardwood and pine bark mulches had few soft ret symptoms. All mulches provided acceptable weed control. Yields throughout the growing season were highest with black polyethylene mulch and lowest with hardwood and pine bark mulches.
Satsuma Mandarin Fruit Size Increased by 2,4-DP
Authors: Agustí M. , Almela V. , Aznar M. , El-Otmani M. , Pons J.
Published: February 2019

The butylglycol ester of 2,4-DP increased final fruit size in `Owari Satsuma' mandarin (Citrus unshiu Marc.). The response magnitude depended on the concentration applied and treatment date. When applied at the end of physiological drop, 50 mg·liter-1 was the most effective treatment for increasing fruit size. Peel density and firmness also were improved. Because no fruit thinning occurred, this auxin seemed to stimulate fruit growth. Chemical name used: 2,4-dichlorophenoxypropionic acid (2,4-DP).
Evaluation of an Electrolyte Leakage Technique to Predict St. Augustinegrass Freezing Tolerance
Authors: Maier F.P. , Lang N.S. , Fry J.D.
Published: February 2019

Stolons of `Raleigh', `Floratam', and FX-332 St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] were sampled from the field between October and March in two consecutive years to evaluate accuracy of an electrolyte leakage (EL) method for predicting freezing tolerance. Lethal temperatures of stolons estimated using EL were compared to those obtained by regrowth tests in the greenhouse. Mean lethal low temperatures for regrowth and EL methods over 12 sampling dates were `Floratam', –4.5C (regrowth) vs. –4.4C (EL); FX-332, –4.2C (regrowth) vs. –4.9C (EL); and `Raleigh', –6.0C (regrowth) vs. –5.4C (EL). A positive correlation (r = 0.81) was observed between EL-predicted and regrowth lethal temperatures for `Raleigh', which exhibited some acclimation during the first sampling year. The EL technique consistently predicted a lower lethal temperature for `Raleigh' than for `Floratam', which corroborates field observations concerning freezing tolerance of these two cultivars.
Ultrastructural Studies of `Kensington' Mango (Mangifera indica Linn.) Heat Injuries
Authors: Jacobi Keryl K. , Gowanlock Don
Published: February 2019

Mature green `Kensington' mango fruit were submerged in hot water at 46C until the fruit center reached 45C and then held for 30 minutes. The fruit were allowed to ripen for 7 to 10 days after the hot water treatment, and then damaged areas of skin and mesocarp tissue were prepared for observation by scanning and transmission electron microscopy. Heating-related injuries included rupturing the patterned cuticle and exocarp and exposing the underlying cells and hollow cavities (which varied in size and shape) randomly distributed within the mesocarp beneath the skin. Starch deposits still were present in the mesocarp parenchyma cells. The cell walls of damaged mesocarp parenchyma cells were convoluted and thickened in places. The injury suggested disruption of enzymes involved in carbohydrate metabolism.
DNA Fingerprints in Plants Using Simple-sequence Repeat and Minisatellite Probes
Authors: Sharon Dror , Adato Avital , Mhameed Samir , Lavi Uri , Hillel Jossi , Gomolka Maria , Epplen Conny , Epplen Jorg Thomas
Published: February 2019

Plant genomes contain polymorphic repetitive sequences that can be used as DNA markers. Minisatellites (16 to 64 bp per repeat) and simple-sequence repeats (2 to 6 bp per repeat) are the most polymorphic markers found in plant and animal genomes. In this study, the hybridizations between genomic DNA and variable number of tandem repeat probes were examined in Arabidopsis thaliana L. (Heynn), onion (Allium cepa L.), tomato (Lycopersicon esculentum L.), wheat (Triticum aestivum L.), avocado (Persea americana Mill.), litchi (Chinensis Sonn.), mango (Mangifera indica L.), and Carica species. Some of the probes detected polymorphic sequences in all the species, but others were useful only for one or two species. None of the probes gave clear band patterns in either onion or wheat. The in-gel hybridization method was similar to Southern blot hybridization using the simple-sequence repeat probes.
Low-temperature Exotherm Measurement Using Infrared Thermography
Authors: Ceccardi Toni L. , Heath Robert L. , Ting Irwin P.
Published: February 2019

Infrared thermography was used successfully to measure the exotherm temperatures during freezing of well-watered and drought-stressed branches of jojoba [Simmondsia chinensis (Link) Schneider]. The exotherms were visualized easily as color changes on the monitor, while computer analysis software was used to plot the resulting temperature vs. time curves, suggesting that freezing sensitivity of jojoba is governed by supercooling. Each branch froze as a unit, and distinct initiation sites were absent. A second, previously tested method of differential thermal analysis was used simultaneously and confirmed the accuracy of the infrared technique. The actual freezing temperature for well-watered tissue was higher (–8C) than for tissue subjected to drought (–10C).
Seed Number and an Asymmetry Index of `McIntosh' Apples
Authors: Brault Anne-Marie , de Oliveira Domingos
Published: February 2019

In `McIntosh' apples (Malus domestica Borkh.), the number of well-formed seeds and the number of fertilized ovules (well-formed plus aborted seeds) were correlated to yield an index of asymmetry for individual fruit. In spite of different flowering and pollination conditions in 1990 and 1991, the index of asymmetry decreased curvilinearly with increases in the number of well-formed seeds and of fertilized ovules in both years.