bluuebunny/crossref_metadata_2025 huggingface dataset:
EVALUATION OF WATERMELON AND RELATED GERMPLASM FOR RESISTANCE TO ZUCCHINI YELLOW MOSAIC VIRUS
Authors: Boyhan George , Norton Joseph D. , Jacobsen Barry J. , Abrahams Bruce R.
Published: February 2019

Of 153 plant introductions (PI), breeding lines, and commercial cultivars tested by mechanical inoculations in the greenhouse, only PI 482261-1, `Egun', PI 494528, PI 386026, and PI 386025 showed any resistance to the Florida strain of zucchini yellow mosaic virus. PI 482261-1 and `Egun' are Citrullus lanatus, the others are citron types, Citrullus colocynthis. This is the first report of resistance in PI 386026, PI 386025, and the cultivar `Egun'.
FERTILIZER MOVEMENT AND SALT ACCUMULATION AS AFFECTED BY IRRIGATION METHOD AND GROUND COVER IN MELON PRODUCTION
Authors: Wiedenfeld Robert , Stubblefield Robert
Published: February 2019

Plastic mulch ground cover and drip irrigation have produced substantial increases in yield and earliness of melons. However, such practices affect water movement, and nutrient and salt distribution in the soil. Salt levels in the soil after a melon crop using drip or flood irrigation increased in bare soil but decreased where plastic mulch had been used. Apparently capillary rise of water in response to surface evaporation brought salts up into the root zone. Very little of the applied N was detectable at the end of the study. However, enhanced early vine growth due to N application where drip irrigated but not where flood irrigated indicated that flood irrigation may have caused earlier N losses. Yield responses to N regardless of irrigation method indicated that early availability may have been most important. Yield increases were found for drip vs flood irrigation, and for plastic mulch vs bare soil, both of which may have been earliness effects; but the later treatments did not get the chance to catch up due to the occurrence of vine decline.
TOMATO FERTIGATION
Authors: Straw R. A. , Mullins C. A.
Published: February 2019

Tomato trials with black plastic mulch, drip irrigation, and fertigation were conducted on a Lily sandy loam soil of medium fertility at Crossville, TN in 1990 and 1991. 'Mountain Pride' tomatoes were fertilized with a broadcast preplant application of 1120 kg ha–1 of 10-4.4-8.3 fertilizer with and without combinations of black plastic mulch and weekly applications of 0.64 cm of water for 12 weeks through drip irrigation. Three black plastic mulch and drip irrigation treatments supplied additional nitrogen and potassium fertilizer through the drip irrigation system. Yields were increased by use of black plastic mulch and by trickle irrigation in 1991. However, additions of fertilizer through drip irrigation had no effect on yields.
COMPUTER COST ESTIMATOR FOR LANDSCAPE INSTALLATION
Authors: Wade Gary L , Thomas William A.
Published: February 2019

Cost estimating and job bidding are among the most complex and time-consuming tasks of landscape professionals. A software package was developed to make cost estimating more accurate and efficient. HORT LAND, computer cost estimator for landscape installation, was developed for IBM compatible PC's using SuperCalc 5 spreadsheet software. The user builds a series of data bases, including an items listing of materials and equipment utilized in his operation along with their associated cost. Then, he defines a series of generic tasks, such as planting a 1-gallon size plant, and refers to the previous items list and associated code numbers for the materials and equipment necessary to install the plant. Once these initial data bases are constructed and saved, the user inputs a plant list, including size and price, then instructs the computer to translate the appropriate data from the initial data bases to arrive at a detailed listing of costs. The program then computes direct job cost and bid price, including overhead and profit.
POSTHARVEST BEHAVIOR OF GREEN AND WHITE ASPARAGUS
Authors: Gonzalez A.R. , Wang T. , Makus D.J. , Mauromoustakos A.
Published: February 2019

Respiration and quality changes were measured in white and green asparagus stored at 20°C. Green asparagus had a higher respiration rate and weight loss than white. Respiration rates decreased and stabilized after 2 days storage in both green and white asparagus. Total phenolics and pulp pH were higher in green than in white asparagus. No significant difference was observed in titratable acidity. Total phenolics and pH decreased while titratable acidity increased during storage of both types of asparagus. Ascorbic acid levels were higher in green spears but soluble solids were higher in white spears. Both ascorbic acid and soluble solids decline during storage. Total chlorophyll content of green asparagus decreased during storage. White asparagus had little chlorophyll. Green color, measured by CDM –a values, followed the same pattern as total chlorophyll.
PACKAGING AND STORAGE OF WATERMELON USING DIFFERENT SHRINK-WRAP FILMS
Authors: Biglete Noida A. , Testin Robert F. , Rushing James W.
Published: February 2019

A triploid watermelon cultivar, `Crimson Trio' and a seeded cultivar, `Mirage', were shrink-wrapped in four different films: Cryovac D940, Cryovac D955, and Magellan film with and without a blended biocide. Unwrapped fruits served as the control. Fruits were stored at either 1.5, 10 and 21°C for three weeks plus an additional week at 21°C to simulate retail marketing. Total soluble solids (TSS) and pulp color measurements were taken after harvest and at the end of the storage period while weight, disease incidence, chilling injury and visual quality rating were monitored at weekly intervals. Results showed that the seedless variety have better postharvest qualities in terms of storage life, TSS and chilling resistance than the seeded variety. Wrapped fruits had less weight loss, higher TSS and better rind color than the unwrapped fruits at the end of the storage period. However, all wrapping treatments, including the biocidal film increased disease incidence compared to unwrapped controls. Also, wrapping did not alleviate chilling injury, which was most severe in fruits stored at 1.5°C and then held at 21°C for one week.
VEGETABLE AMARANTH PERFORMANCE AT DIFFERENT SOIL MOISTURE LEVELS
Authors: Whitehead Wayne F. , Singh Bharat P.
Published: February 2019

The effects of differing soil moisture levels on the vegetative components of vegetable amaranth, Amaranthus tricolor RRC no. 241, were evaluated. A completely randomized design with 10 replications and 4 treatments (3,6,13, & 18% soil moisture) was followed. Leaf, stem, plant, root fresh weight and leaf area (LFW, SFW, PFW, RFW, and LA, respectively)—were recorded 48 days after planting. For each of the vegetative components the only significant difference (P ≤ 0.05) occurred between 3% versus 6-18% soil moistures, with moisture level of 6-18% showing no significant variation among themselves. The mean ranges for LFW (28.3-32.7 g), STW (6.9-9.2 g), PFW (41.3-48.2 g), RFW (8.6-12.8 g), and LA (1049-1222 cm2) across 6-18% soil moisture were approximately four times greater than the vegetative components of 3% soil moisture. From these preliminary results, it appears that vegetable amaranth has the ability to grow and perform well over a 6-18% soil moisture range, indicating an ability to better adjust and adapt to changing soil moisture environments.
USING A GEOGRAPHIC INFORMATION SYSTEM (GIS) TO CHARACTERIZE AND TO MAP GROWING SEASONS FOR VEGETABLES
Authors: Logan Joanne , Coffey David L.
Published: February 2019

Vegetable production has become a multi-million dollar activity in Tennessee. The large number of options of planting dates and maturity classes of different vegetable species and cultivars result in a flexible, yet confusing, situation for the grower. A plentiful supply of vegetables for the processor, fresh market, or family table can be assured by the proper scheduling of planting and harvest of different crops and cultivars. Growers have very limited access to climatic data oriented to vegetable production in their locations. For the most part, they depend on planting maps on the backs of seed packets, or on extension bulletins with very general planting and harvest date recommendations. Tennessee consists of 4 climatic divisions that do not adequately describe the multitude of climates due to the diverse topography. The objective of this research was to create GIS maps of climatic variables important to vegetable production. Maps of temperatures, growing degree days, and rainfall, freeze and heat stress probabilities based on data from 72 locations in Tennessee were used to characterize the growing seasons for different vegetables.
INFLUENCE OF THREE MULCHING SYSTEMS ON VEGETABLE YIELD AND SOIL LOSS UNDER HIGHLY ERODIBLE CONDITIONS
Authors: Byers Matthew , Antonious George , Bishop Keenan
Published: February 2019

Using USLE standard plots, on 10% slope, on uniform Lowell silt loam soil, the influence of three soil treatments and two representative vegetable crops on soil runoff losses was determined. Yields (1990 and 1991) for each crop × soil treatment combination were also determined. Soil losses were determined by catching runoff, filtering, air drying and massing representative samples. With total volume per plot known, grams sediment per liter runoff were converted to kg/ha. Overall mean yields of pepper were 2.9, 4.7, and 3.7 and pumpkin were 47.3, 87.1 and 76.1 kg/7.3-m row, respectively. Mean sediment losses over five rainfall events in 1991 in peppers were 52, 1158, and 5362; and in pumpkins were 72, 3011, and 7271 kg/ha, for fescue, plastic and no-mulch treatments, respectively. Clearly, fescue in .6-m strips between rows, with comparable yields demonstrated (1991) and negligible sediment losses, was the best management practice (BMP).
EFFECT OF ROOT LENGTH AND SPACING ON ESTABLISHMENT OF BLACKBERRY PLANTS
Authors: Buckley Blair , Clark John R. , Pee K.C. , Johnson Charles E.
Published: February 2019

Field tests at two locations examined the influence of length and spacing of root propagules on blackberry plant establishment. Root propagules 10.2 cm long spaced 61 cm resulted in greater emergence, plant stand, and shoot growth than 5 cm and 2.5 cm root propagules. Differences in emergence and shoot growth between 10.2 cm progagules spaced 61 cm and 5 cm propagules spaced 61 cm were non-significant. Greenhouse tests compared four lengths of root propagules (15.2 cm, 10.2 cm, 5cm, 2.5 cm) for production of nursery plants. Percent emergence, time of emergence, and number of shoots per propagule produced from 2.5 cm propagules were comparable to results from 15.2 cm and 10.2 cm propagules.
BREEDING FOR RESISTANCE TO ROSETTE (DOUBLE BLOSSOM) DISEASE IN BLACKBERRY
Authors: Gupton Creighton L.
Published: February 2019

Crosses between `Humble' and five other blackberry cultivars were made to determine the efficacy of `Humble' as a source of resistance to rosette (incited by Cercosporella rubi). Seven cultivars and three selections were planted at a disease free location and at a location where rosette is known to occur to determine the effect of double blossom on yield, berry weight, and ripening date. `Cheyenne' X `Humble,' `Humble' X `Brazos,' and `Navaho' X (`Humble' X `Brazos') produced progenies with various levels of resistance. Promising selections were made from the latter two crosses. Genotype X location interaction was significant for yield and not significant for either Julian date of 50% ripe fruit or weight per berry. These results suggest that rosette reduces yield but has little if any effect on weight per berry or ripening date. `Shawnee' and `Choctaw' were the highest yielding cultivars under disease free conditions; however, their yields were low in the test where they were infected with rosette. `Brazos,' `Choctaw,' and `Rosborough' were the earliest ripening and `Navaho' was the latest ripening cultivar.
TRAINING SYSTEM AFFECTS PERFORMANCE OF TABLE GRAPE CULTIVARS
Authors: Wolfe Dwight , Brown Gerald R.
Published: February 2019

Each of the grape cultivars [Vitis species, (L) Batch], `Concord', `Himrod', `Challenger', `Reliance', `Glenora', `Moored', planted June 1983, and `Mars' planted Spring, 1987, was trained to the 4-cane Kniffin (KN) and the Geneva Double Curtain (GDC) systems. Yield per vine, pruning weight, number of nodes, cluster weight, number of berries per cluster, berry weight, and percent soluble solids were recorded. Vines from `Reliance' trained to the KN system produced fruit with significantly higher percent soluble solids than did vines trained to the GDC. No significant differences in percent soluble solids were observed between the two training systems for the other cultivars. `Concord' produced more kg/vine of pruning weight when trained to the KN system than when trained to the GDC. Pruning weight did not differ significantly between the two training systems for the other cultivars. Cultivars more productive (yield/vine) on the GDC trellis were `Concord', `Himrod', `Reliance' and `Moored' whereas `Challenger' was more productive when vines were trained to the KN system. No differences between the two training systems were observed for `Glenora' or `Mars'.
DEBLOSSOMING IN EARLY SEASON AS IT AFFECTS YIELD DISTRIBUTION OF JUNEBEARING STRAWBERRY IN A SUBTROPICAL CLIMATE GREENHOUSE
Authors: Rubeiz I. G. , Khoury R. Y. , Al-Assir I. A.
Published: February 2019

Blossom removal of “Douglas” strawberry for the first two weeks of flowering, was studied as to its effect on fruit yield of plants grown inside a greenhouse located in a subtropical climate. Deblossoming resulted in a slightly lower early yield than undeblossomed plants. From the fourth till the ninth week of harvest, deblossomed plants slightly outyielded undeblossomed plants. Yield became similar among both treatments from the tenth week till the last week of harvest (week 17). Weekly and total yields were not significantly different (P> 0.05) among the treatments. Deblossomed plants yielded 29.5 kg/10m2, whereas undeblossomed plants yielded 28.2 kg/10m2, during the harvest period. Since these plants are grown for one season in the greenhouse, from November till June after which they are dug out, there will be no future carry over effect of deblossoming on these plants. Furthermore, the highest economical returns are from the first weeks of harvest, hence, any treatment which reduces early yield in return for a higher later yield, has to be weighed against the higher economical returns of the lower but earlier yield.
Role of Sucrose in Bud Development and Vase Life of Cut Liatris spicata (L.) Willd.
Authors: Han Susan S.
Published: February 2019

Sucrose addition to the vase solution improved the postharvest qualities of cut liatris by increasing the length of inflorescences showing color and by prolonging the vase life of the spikes. The main effect of sucrose was on the development and opening of the flower heads with minimal effect on their longevity. Pulsing with concentrations of sucrose ≥10% for 20 hours prolonged the vase life of the spikes. Responses of spikes to the pulsed treatment varied greatly due to the differences in their degree of leafiness, thus limiting its commercial application. A continuous supply of 2.5% or 5% sucrose in the vase solution allowed most of the flower heads on the spikes to develop and doubled the vase life of the spikes.
Ability of `Valencia' Sweet Orange to Cold-acclimate on Cold-sensitive Citron Rootstock
Authors: Yelenosky G. , Vu J.C.V.
Published: February 2019

Greenhouse-grown l-year-old sweet orange trees [Citrus sinensis (L.) Osbeck cv. Valencia] on cold-hardy trifoliate orange [Poncirus trifoliata (L.) Raf.] and cold-sensitive citron (C. medica L.) rootstocks were exposed to cold-acclimation conditions and freeze-tested at -6.7C for 4 hours in a temperature-programed walk-in freezer room. Nonhardened trees generally did not survive the freeze, whereas cold-hardened trees survived with no wood kill on either rootstock. Essentially, all leaves died or abscised during the subsequent 5 weeks in the greenhouse. Freeze survival did not separate rootstocks nor did supercooling in separate trials where Yalencia' wood reached –8.8C before apparent nucleation. Increases in concentration of carbohydrates and proline and decreases in water content in Yalencia' leaves during cold hardening were generally associated with increased freeze tolerance. Other tests, that matched 9-month-old seedlings of citron with trifoliate orange rootstock, showed clear differences in the superior cold acclimation of trifoliate orange over citron, which, however, performed better than expected.
Pyrenochaeta terrestris Microsclerotia Production and Pigmentation on Onion Roots
Authors: Biles Charles L. , Holland Mel , Ulloa-Godinez Mauricio , Clason Dennis , Corgan Joe
Published: February 2019

Experiments were conducted to determine variation of in vitro microsclerotia production, pigmentation, and growth of five Pyrenochaeta terrestris (Hans.) Gorenz, Walker, and Larson isolates from Texas and New Mexico. Isolates of P. terrestris, the causal agent of pink root rot, were placed on agar with lo-mm-long sections of sterile onion (Allium cepa L.) roots. Microsclerotia were present after 20 days at 20, 25, 27, or 32C, with the number of microsclerotia dependent on the isolate. Microsclerotia were absent at 35C. One isolate produced few microsclerotia at all temperatures. Optimum temperatures for growth on potato dextrose agar for the isolates tested were 25 and 27C. Pigment production in roots on agar varied depending on isolate and temperature. Three isolates produced high levels of pigment in onion roots at 15, 20, 25, and 27C. A New Mexico isolate produced significantly less visible pigment than the other New Mexico and Texas isolates. One isolate produced very little pigment at all temperatures tested. Constant fluorescent light stimulated pycnidia production in one isolate and reduced microsclerotia production in all other isolates. Isolates varied significantly in microsclerotia production and pigment synthesis.
MODELING THE OCCURRENCE OF THE FLOWERING PEAK OF MACADAMIA NUT (MACADAMIA INTEGRIFOLIA)
Authors: Hwang Sam-Gwang , Kobayashi Kent D. , Nagao Mike A.
Published: February 2019

The objective of this study was to develop models to predict the occurrence of the flowering peak of macadamia nut (Macadamia integrifolia). At Hilo and Kona, weather and `Ikaika' flowering data were collected. The best model that described the time from the starting date of the flowering season to the highest flowering peak was days = 249.15 + 0.12 (total growing degree days) - 5.81 (maximum temperature) - 6.26 (minimum temperature). The model predicted the highest peak 4 days before it occurred at Hilo and 4 days after it occurred at Kona. Two statistical models, one for each location, were developed to predict the time from the starting date of the flowering season to the first peak. At Hilo, the best model was days = 118.61 - 0.11 (total growing degree days) + 0.000168 (total solar radiation). The model predicted the first peak 1 day before it occurred in the field. The best model at Kona was days = (-156.34) + 12.67 (minimum temperature) + 0.01 (total growing degree days). The model predicted the first peak on the day it occurred in the field. These models may aid growers in predicting the flowering peak so that bees can be brought into orchards at the proper time to increase cross-pollination.
Vegetative Propagation of Eastern Redcedar by Stem Cuttings
Authors: Henry Paul H. , Blazich Frank A. , Hinesley L. Eric
Published: February 2019

Studies were conducted to investigate the effects of season (timing), IBA application, genotype, crown position, type of cutting (straight vs. heel), cutting length, and stock plant age upon adventitious rooting of stem cuttings of eastern redcedar (Juniperus virginiana L.). Genotype had a strong influence on percent rooting, root count, and root length of 4-year-old trees. With trees of this age, percent rooting was maximized (87%) with hardwood cuttings taken in January and treated with 5000 ppm IBA. Crown position from which cuttings were collected did not influence rooting. Straight cuttings, with or without a light wound, rooted at a significantly higher percentage (78%) than heel cuttings (52%). With 30-year-old trees, cuttings from the lower third of the crown rooted at a significantly higher percentage (67%) than cuttings from the middle third (43%). Better rooting was obtained with straight (68%) than heel (47%) cuttings. Cutting length affected rooting, with root count and length highest in longer cuttings. Increased tree age reduced rooting, although cuttings from 40-year-old trees retained substantial rooting capacity. Chemical name used: 1 H-indole-3-butyric acid (IBA).
Lead and Arsenic in Two Apricot Cultivars and in `Gala' Apples Grown on Lead Arsenate-contaminated Soils
Authors: Creger Timothy L. , Peryea Frank J.
Published: February 2019

Concerns about food safety prompted a case study of the arsenic and Pb contents of tree fruits grown on lead arsenate-contaminated soil. The arsenic concentration in apricot (Prunus armeniaca L.) and `Gala' apple (Malus domestica Borkh.) fruit was positively related to concentrated HCl-extractable soil arsenic. Fruit arsenic in both species did not exceed 70 μg·kg-1 fresh weight (fw). Fruit Pb was below the limits of detection of 20 μg·kg-1 fw for apricot and 24 μg·kg-1 fw for apple. All of these concentrations are substantially below levels associated with human health risk. `Riland' apricot trees did not show arsenic phytotoxicity at soil, fruit, and leaf arsenic concentrations associated with phytotoxicity symptoms in `Goldrich' apricots. The apple trees showed no visual symptoms of arsenic phytotoxicity.
Toxic Effects and Residues in Six Nectarine Cultivars following Methyl Bromide Quarantine Treatment
Authors: Hartsell P.L. , Harris C.M. , Vail P.V. , Tebbets J.C. , Harvey J.M. , Yokoyama V.Y. , Hinsch R.T.
Published: February 2019

Residues and the toxic effects of methyl bromide (MB) were determined in fumigation tests with six cultivars of nectarine [Prunus persica (L.) Batsch. var. nectarina (Ah.) Maxim.]. `Fantasia', `Firebrite', and `Summer Grand' were treated in wooden field bins in a commercial facility, whereas `May Fire', `May Glo', and `May Diamond' were fumigated in smaller fiberglass chambers. The treatment of 48 g MB/m3 for 2 hours at 21C and normal atmospheric pressure with a load factor of 50% (179 kg·m-3) was that proposed for quarantine eradication of the codling moth (Cydia pomonella L.). The appearance of the fruit, as well as the soluble solids content, were not affected by the MB fumigation; however, ripening of `May Grand' and `Firebrite' was delayed slightly. Sorption of MB was 55%. Desorption rates of organic bromide were not significantly different among the six treated cultivars; all fruits contained <0.001 μg·g-1 after 7 days of storage at 2.5C. Inorganic bromide residues in all treated fruits were <8.0 μg·g-1.
Growth and Net Photosynthetic Rate of Solanun tuberosum in Vitro under Forced and Natural Ventilation
Authors: Kubota Chieri , Kozai Toyoki
Published: February 2019

Growth and net photosynthetic rate of potato (Solanum tuberosum L.) `Benimaru' plantlet in vitro were studied under a conventional photomixotrophic condition [with 20 g sucrose/liter in the medium and under 70 μmol·m-2·s-1 photosynthetic photon flux (PPF)] with minimal ventilation (MV) and under photoautotrophic conditions (without sugar in the medium and under 190 μmol·m-2·s-l PPF) with enhanced natural ventilation using an air diffusive filter (DV) or with forced ventilation (FV). Fresh weight of the plantlets cultured in the FV and DV treatments was 2.4 times that of the plantlets cultured in the MV treatment. Net photosynthetic rate and dry weight per plantlet were the highest in FV followed by DV. For photoautotrophic micropropagation, FV was superior to DV.
Morphological Differences among Apple Leaf Types
Authors: Schechter I. , Proctor J.T.A. , Elfving D.C.
Published: February 2019

Leaf characteristics of mature `Sturdeespur Delicious'/MM.106 apple trees (Malus domestica Borkh.) were studied in two experiments. In 1989 canopy foliage on fruiting trees was divided into shoot leaves, leaves on nonfruiting spurs, and leaves on fruiting spurs. Shoot leaves were the heaviest, the largest, and contained the highest internal gas volume and chlorophyll content. The two spur-leaf types differed in their leaf characteristics except for stomate density. In 1990 shoot and spur leaves on nonfruiting spurs on fruiting trees had lower leaf water content than those leaves on nonfruiting trees. All other shoot-leaf characteristics were similar. Leaves on nonfruiting spurs on nonfruiting trees were larger than those on fruiting trees.
Interactions of Ethephon, Whitewashing, and Dormant Oil on Peach Pistil Growth, Hardiness, and Yield
Authors: Durner Edward F. , Gianfagna Thomas J.
Published: February 2019

Six-year-old peach trees [Prunus persica (L.) Batsch] were sprayed with ethephon (100 mg·liter–1) in Oct. 1989, whitewashed in Jan. 1990, and sprayed with dormant oil on one or two dates in Mar. 1990 to study possible interactive effects on flower bud hardiness, pistil growth, time of bloom, and yield. Flower buds from ethephon-treated trees supercooled to a lower temperature [mean low temperature exotherm (MLTE) of –18.5C] than buds from nontreated trees (MLTE of –17.7C) in February; there was no main effect of whitewashing or any interaction with ethephon. No treatment effects on hardiness were detected in March. Ethephon-treated pistils were smaller than nontreated pistils, and pistils from buds on whitewashed trees were smaller than those on nonwhitewashed trees. No main effects or interactions of dormant oil on pistil size were detected. Ethephon and whitewashing delayed bud development during bloom, but prebloom oil application(s) had no effect. Buds from ethephon-treated and whitewashed trees were more tolerant of freezes during bloom than buds from oil-sprayed trees, and yield was enhanced by ethephon and whitewashing. Prebloom oil sprays reduced yield compared with controls. Chemical name used: 2-chloroethylphosphonic acid (ethephon).
Leaf Unfolding Rate in Begonia × hiemulis
Authors: Karlsson Meriam G.
Published: February 2019

The rate of leaf unfolding as a function of temperature was determined for Begonia × hiemalis Fotsch under long-day (16 hours of light) conditions before flower initiation. Irradiance was maintained at 280 ± 20 μmol·m–2·s–1 (16.1 mol·m–2·day–l). The two cultivars Hilda and Ballet had similar rates of leaf unfolding in the range from 13 to 28C. The rate increased to a maximum of 0.116 leaves/day at 21C and then decreased at higher temperature. The following quadratic function (where T is the temperature in °C) was selected to describe initial long-day leaf unfolding rate in B. × hiemalis: leaves/day = -0.2083 + 0.03145 × T – 0.0007631 × T2, (r2 = 0.97). The leaf unfolding response to temperature varied for plants of `Hilda' and `Ballet' during short days (10 hours of light) following the initial long-day period. Plants of `Ballet' continued to unfold leaves at a similar rate as under initial long photoperiods, while the leaf unfolding rate for `Hilda' decreased to half the rate observed under long days.
Responses of Garden Chrysanthemums to Daylength
Authors: Cockshull Kenneth E. , Kofranek Anton M.
Published: February 2019

Garden chrysanthemums [Dendranthemum ×grandiflorum (Ramat.) Kitamura] are characterized by early flowering in September and October when grown out-of-doors and by rapid flowering in short days (SD). However, as rooted cuttings of these cultivars frequently have flower buds present at the time of planting, their true response to daylength cannot readily be determined. Vegetative shoots were obtained by growing rooted cuttings in long days (LD), removing the terminal bud, and then pinching the emerging side shoots at a very early stage. On transfer to SD, the vegetative secondary side shoots quickly initiated flower buds that developed to anthesis more rapidly than those of `Bright Golden Anne' (BGA), a lo-week response group cultivar. `Bandit', `Buckeye', `Compatriot', `Freedom', `Jackpot', and `Sunburst Cushion' appeared to be in the 7-week response group, with `Baby Tears' in the 6-week and `Powder River' in the 8-week response groups. All cultivars rapidly initiated flower buds in LD and, although they produced significantly more leaves than in SD, flower initiation began within ≈13 LD from pinching. When pinched twice and grown using black cloth in summer, garden chrysanthemums can form attractive, uniformly flowering pot plants. Their rapid-flowering characteristic could also be of value in breeding programs for cut-flower chrysanthemums.
Cordyline terminalis Plants Respond to Foliar Sprays and Medium Drenches of Paclobutrazol
Authors: Hagiladi A. , Watad A.A.
Published: February 2019

Potted Cordyline terminalis L. `Prins Albert', a foliage plant, was treated with foliar sprays or growth medium drenches of paclobutrazol for plant growth control. Paclobutrazol effectively reduced shoot length measured 4 months following application, the drench being more effective than the spray. Application of paclobutrazol at 200 ppm by either method gave a desirable compact and marketable product. Drench applications at 1000 ppm promoted side-shoot formation. Leaf morphology was altered from an elongated to a more oval form as the paclobutrazol concentration increased, but leaf count was not affected by paclobutrazol, except for the highest drench concentration, which reduced leaf count by 10%. Chemical name used: β– [(4-chlorophenyl)methyl] –α– (1,1-dimethylethyl)-1H-1,2,4-triazole-1-ethanol (paclobutrazol).
Inheritance of Growth Habit and Qualitative Flowering Response in Lima Beans (Phaseolus lunatus L.)
Authors: Erickson H.T.
Published: February 2019

Indeterminate growth habit in lima bean is inherited as a single gene dominant. A qualitative short-day photoperiodic response for flowering appears to be controlled by duplicate dominant genes with coupling linkage to the gene for growth habit. Partial epistasis of the determinate growth habit on genes for short-day response is suggested.
Restriction Fragment Length Polymorphisms in Rose and Their Use for Cultivar Identification
Authors: Hubbard M. , Kelly J. , Rajapakse S. , Abbott A. , Ballard R.
Published: February 2019

We have identified cloned rose DNA fragments that detect restriction fragment length polymorphisms (RFLP) in rose (Rosa ×hybrida) cultivars. RFLP can be used as genetic markers for identification, certification, and patent protection. By comparing RFLP patterns for each of six probes, we have been able to characterize eight cultivars. These results confirm that RFLP analyses are useful for rose cultivar identification and may provide a means for protecting patent rights to new cultivars.
Frequency of Zygotic Seedlings from Five Polyembryonic Mango Rootstocks
Authors: Schnell Raymond J. , Knight Robert J.
Published: February 2019

Five isozyme systems were used to detect zygotic seedlings from five polyembryonic cultivars of mango (Manifera indica L.). Significant differences were found between cultivars (x2 = 35.53, P < 0.001) for the percentage of zygotic and nucellar seedlings detected. The range of variation in the percentage of off-types was from 0% in 13-1 to 64% in Golek. The percentage in Sabre was 4%, and 24% and 36% in Tupentine and Madoe, respectively. Three of eight rootstock mother trees of Turpentine were determined to be off-types.
A Rapid, Objective Method to Index Leaf Chlorosis in Spinach
Authors: Santos Jose Reynaldo A.
Published: February 2019

Chlorophyll extraction (TCHL) and spectrophotometric (CM45) techniques were compared with a visual (VISINDX) method of indexing chlorosis on spinach (Spinacea oferacea L.) leaves that show various degrees of white rust (Albugo occidentalis G.W. Wils.) infection. The CM45 method gave a good fit (R2 = 0.91) when its readings were regressed against MSINDX ratings. Both regression and cluster analyses indicated that the CM45 method was more efficient than the TCHL method in separating leaves into unique chlorosis severity classes.
Rootstock, Pruning, and Soil Fumigation in Relation to Dormancy and Cold Hardiness of `Redhaven' Peach
Authors: Harber Renee M. , Nyczepir Andrew P. , Yadava Umedi L. , Sharpe Ronald R.
Published: February 2019

The effects of rootstock, pruning, and preplant soil fumigation on floral bud dormancy status and shoot cold hardiness of `Redhaven' peach [Prunus persica (L.) Batsch] trees were monitored. Dormancy status, expressed as percent floral budbreak, was significantly affected by rootstock and pruning, although differences were small. In late January, significant interactions occurred between rootstock and pruning treatments, as well as between pruning and soil treatments. Pruning of trees on Lovell rootstock resulted in significantly lower budbreak as compared to trees on Nemaguard and unpruned trees on Lovell. Also, for trees pruned in December, higher budbreak was associated with those growing in fumigated vs. nonfumigated soil. Treatment effects on dormancy status did not correspond with treatment effects on hardiness. In fact, differences in hardiness were minimal and probably not biologically meaningful.
Seedling Root Morphology and Shoot Growth after Seed Priming or Pregermination of Bell Pepper
Authors: Stoffella Peter J. , Di Paola Michele Lipucci , Pardossi Alberto , Tognoni Franco
Published: February 2019

Primed, pregerminated, or nontreated seeds of bell pepper (Capsicum annum L.) `Early California Wonder' were grown in controlled conditions for 14 days in glass tubes containing a gel medium. The number of basal roots (one per plant), lateral roots (one per plant), and taproot length (64 mm) did not differ between seed treatments 14 days after seeding. Roots of seedlings from nontreated seeds weighed more than seedlings from primed seeds, and the seedlings had smaller shoot: root ratios than those from pregerminated or primed seeds. Seedlings from pregerminated seeds had heavier and taller shoots than seedlings from nontreated or primed seeds. Taproot length from 1 to 6 days after radicle protrusion increased linearly for all seed treatments. Seedlings from pregerminated seeds initially had longer taproots but had slower linear taproot growth up to 6 days after seeding than seedlings from nontreated or primed seeds.
Temperature and Duration of Pretreatment Effects on Growth and Development of Geraniums
Authors: Gagnon Serge , Dansereau Blanche
Published: February 2019

Geranium seedlings (Pelargonium ×hortorum Bailey `Smash Hit Red') were given various cold pretreatments (CP) to obtain more rapid adaptation to constant or split-night temperature regimes. The six following CP were used: either 13C or 17/13C for 5, 10, or 15 days. The effect of these CP given at seedling stage was compared with that of control plants held at 17C at night. The CP did not significantly increase the time to first visible flower buds or to anthesis. The number of flowering stems, plant height, shoot dry weight, and leaf area of control plants were not significantly different from plants receiving CP.
Response of Creeping Bentgrass to Spring-applied Herbicides
Authors: Shim Sang Ryul , Johnson B.J.
Published: February 2019

Creeping bentgrass (Agrostis palustris Huds.) putting greens are commonly infested with crabgrass (Digitaria spp.) and goosegrass [Eleusine india (L.) Gaertn.]; however, many herbicides have the potential to severely injure this turfgrass species. A field investigation was conducted over 2 years to determine the tolerance of creeping bentgrass to various herbicides. Trifluralin plus benefin (2.2 to 6.7 kg·ha-1), dithiopyr (0.37 to 1.1 kg·ha-1), and prodiamine (0.5 to 1.7 kg·ha-1) did not injure creeping bentgrass. Pendimethalin caused only slight injury when applied at 3.4 kg·ha-1, but injury increased in 1 of 2 years when applied at ≥6.7 kg·ha-1. Creeping bentgrass was severely injured when treated with benefin plus oryzalin (≥4.5 kg·ha-1), fenoxaprop (0.07 kg·ha-1), and oxadiazon (3.4 kg·ha-1) granular and WP formulations and, therefore, should not be applied to the turf. Chemical names used: N -butyl-N -ethyl-2, 6-dinitro-4-(trifluoromethyl) benzenamine (benefin); S,S -dimethyl 2-(difluoromethyl-4-(2-methylpropyl)-6-(trifluoromethyl-3, 5-pyridinedicarbothioate (dithiopyr); (±) 2-[4-[(6-chloro-2-benzoxazolyl)oxy]phenoxy]propanoic acid (fenoxaprop); 4-(dipropylamino)-3,5-dinitrobenzenesulfonamide (oryzalin); 3-[2,4-dichloro-5-(l-methylethoxy)phenyl]-5-(1,1-dimethylethyl)-1,3,4-oxadiazol-2-(3H)-one (oxadiazon); N -(1-ethylpropyl)-3,4-dimethyl-2,6-dinitrobenzenamine (pendimethalin); 2,4-dinitro N,N -dipropyl-6-(trifluoromethyl)-1,3-benzenediamine (prodiamine); 2,6-dinitro-N-N -dipropyl-4-(trifluoromethyl)benzenamine (trifluralin).
Reciprocal Grafts of Standard and Dwarf Peach Alter Dry-matter Partitioning and Root Physiology
Authors: Glenn D.M. , Scorza R.
Published: February 2019

In reciprocal grafts of tall (`Elberta' and `Loring') and dwarf (`Empress' and `Juseito') peach (Prunus persica Batsch.) phenotypes, we measured dry-matter partitioning, resistance to root system water flow, and phytohormone content of xylem exudate. Scion characteristics determined the phenotype and growth characteristics of the tree irrespective of the rootstock. Tall phenotypes had higher dry weight and lower root resistance to water flow than dwarf phenotypes. Cytokinin-like activity and auxin levels in xylem sap were higher in dwarf than in tall phenotypes; whereas gibberellin-like activity was unaffected by either rootstock or scion. The scion of peach influenced phytohormone levels and resistance to water flow in the root system in addition to root and shoot growth.
The Use of Leaf Parts to Estimate the Cold Hardiness of Southern Magnolia (Magnolia grandiflora L.)
Authors: Lindstrom Orville M.
Published: February 2019

Whole, half, and quarter leaves and leaf disks were used to make laboratory estimations of the cold hardiness of Magnolia grandiflora. The effects of ice nucleation temperatures, length of exposure to nucleating temperatures, rates of temperature drop, thawing regimes, and methods of injury analysis were investigated for each leaf type in the fall and midwinter. In general, whole and half leaves responded more consistently to freezing tests than did quarter leaves and leaf disks. The most critical factors in the freezing procedure are the temperature at which the samples are nucleated with ice crystals and the regime in which the samples are warmed. These data suggest that whole and half leaves can effectively be used to reliably predict the cold hardiness of southern magnolia leaves.
Adventitious Bud Formation from Callus Cultures of Japanese Persimmon
Authors: Tao Ryutaro , Sugiura Akira
Published: February 2019

Callus cultures were initiated in the dark from leaf primordia, stem internodes, and young leaves of adult Japanese persimmon (Diospyros kaki L.) to induce adventitious buds. A high frequency of regeneration occurred on Murashige and Skoog medium (MS) with half the normal NH4NO3 and KNO3 concentration (1/2N) and containing 10 μm zeatin or 1 μm 4PU-30 in combination with 0.1 μm IAA, or MS(1/2N) medium containing 0.03 to 0.1 μ m IAA or 0.01 to 0.03 μm NAA combined with 10 μm zeatin. No significant differences in the capacity of regeneration were observed among the calli from different explant sources. Only eight of 16 cultivars formed adventitious buds on MS(1/2N) medium containing 10 μm zeatin and 0.1 μm IAA, with the percentage of explants forming adventitious buds ranging from 2% to 72%. Chemical names used: indole3-acetic acid (IAA); 1-naphthaleneacetic acid (NAA); N-phenyl-N'-(2-chloro-4-pyridyl)urea (4PU-30).
Performance of Drainage Lysimeters for the Evaluation of Water Use by Asian Pears
Authors: Chalmers David J. , Andrews Preston K. , Harris Kevin M. , Cameron Ewen A. , Caspari Horst W.
Published: February 2019

The design of a type of drainage lysimeter, as tested with trees of Pyrus serotina Rehder var. culta Rehder `Hosui' is described. All lysimeter operations and monitoring of irrigation and drainage volumes were managed by a “multi-tasking” controller/datalogger. It was possible to apply different irrigation levels to each of three sets of four random lysimeters. Evapotranspiration (ET) was calculated using a conservation of water equation, with differences between irrigation inputs and drainage outputs corrected for changes in soil-water content. ET ranged between 3.3 and 10.7 liters/tree per day in well-watered, noncropped trees in late Summer and Fall 1990. These rates correspond to ET of 0.13 to 0.43 liter·cm-2·day-1 and 0.96 to 3.10 liters·m-2·day-1 on trunk cross-sectional area and canopy area bases, respectively. The correlation coefficient between ET and Class A pan evaporation was >0.9 during this period. Weekly crop coefficients for the well-watered trees averaged 0.52 when calculated on a canopy-area basis. When irrigation was withheld for 18 days, the crop coefficient declined to 0.38. There were no differences in ET between trees growing in the two soil profiles, despite significant differences in soil water distribution.
Flower Bud Stage and Chill Hours Influence the Activity of GA3 Applied to Rabbiteye Blueberry
Authors: NeSmith D.S. , Krewer Gerard
Published: February 2019

Individual flower clusters of `Tifblue' rabbiteye blueberry (Vaccinium ashei Reade) were treated with 300 ppm GA at several flower bud stages to determine the activity of the growth regulator in promoting fruit set. Applications were made one time only at a specified stage of flower development, or once followed by a second application. A single application of GA when flower buds had elongated but corollas had not expanded (stage 5) led to the largest increase in fruit set. Two applications of GA, 10 to 18 days apart, increased fruit set compared with a single application at flower developmental stages other than stage 5. Fruit set promoted by a single spray of GA imposed on fully expanded corollas (stage 6) decreased with increasing number of chill hours (350, 520, 760, or 1150). Chemical names used: gibberellic acid (GA).
Physiological Changes during Ripening of Raspberry Fruit
Authors: Perkins-Veazie Penelope , Nonnecke Gail
Published: February 2019

Raspberry (Rubus idaeus L., `Heritage') fruit were harvested at six stages of color development to determine the relationship between quality attributes and physiological changes during ripening. Soluble solids concentration and fruit weight increased, whereas titratable acidity decreased during ripening. Fruit darkened and color saturation increased with maturity. Raspberry fruit exhibited a nonclimacteric pattern of respiration, and ethylene (C2H4) was detected only after red pigment developed. Respiration and C2H4 production of whole fruit were similar to those of drupes. Ethylene-forming enzyme activity commenced in drupes and receptacle tissue from fruit at the yellow and mottled stages, respectively. These data indicate that ripening in raspberry fruit is independent of C2H4 production and is nonclimacteric.
Magnetic Resonance Imaging of Water in Flower Buds of Blueberry
Authors: Rowland Lisa J. , Liu Dehua , Millard Merle M. , Line Michael J.
Published: February 2019

Dormant and chilled highbush blueberry (Vaccinium corymbosum L.) flower buds were examined by magnetic resonance imaging (MRI). T2 relaxation times of water molecules were too short to create images from flowers within buds that were dormant and had received no chilling, but they were sufficiently long to create images from buds that had their chilling requirement satisfied. To explain the change in relaxation times, we concluded that water is present in a motionally restricted form in flowers of dormant blueberry buds and in a freer form in flowers of buds after the chilling requirement has been satisfied. T2 values for chilled blueberry buds indicated that one population of water molecules with a detectable T2 time was present in flowers of chilled buds with a relaxation time of ≈8 to 15 ms.
Light Acclimatization Potential of Leea coccinia and Leea rubra Grown under Low Light Flux
Authors: Sarracino J.M. , Merritt R. , Chin C.K.
Published: February 2019

Two foliage plant species, Leea coccinia L. and Leea rubra L., exhibited lower light compensation points and faster rates of acclimatization than Ficus benjamina L. when moved from full sun to dense shade, i.e., from 15.7 to 0.26 or 0.09 mol·m·-2day-1. Light compensation points were reduced up to 75% for L. coccinia and 71% for L. rubra after 25 days under these conditions. Uptake of CO2 increased from 65% to 179% and 34% to 118% for L. coccinia and L. rubra, respectively, while respiration rates were reduced from 73% and 76% to 59% to 68%, respectively. Ficus benjamina plants died under similar conditions.
Pollen Viability and Vigor in Hybrid Southern Highbush Blueberries (Vaccinium corymbosum L. ×spp.)
Authors: Lang Gregory A. , Parrie E. James
Published: February 2019

Pollen from six southern highbush blueberry cultivars derived from Vaccinium corymbosum L. and one or more other species (V. darrowi Camp, V. ashei Reade, and V. angustifolium Aiton) was incubated on nutrient agar to determine tetrad viability, pollen tube growth rates, and incidence of multiple pollen tube germinations. `Avonblue' pollen had a significantly lower tetrad germination percentage than `Georgiagem', `Flordablue', `Sharpblue', `Gulfcoast', or `O'Neal', all of which had >90% viable tetrads. The in vitro growth rate of `O'Neal' pollen tubes was significantly higher than the growth rates of `Sharpblue' and `Georgiagem pollen tubes. Of those tetrads that were viable, more than two pollen tubes germinated from 83% and 91% of the `Gulfcoast' and `Sharpblue' tetrads, respectively, while only 11% of the `Flordablue' tetrads produced more than two pollen tubes. The total number of pollen tubes germinated per 100 tetrads ranged from 157 (`Flordablue') to 324 (`Sharpblue'), resulting in actual pollen grain viabilities ranging from 39% to 81%. Genetic differences in pollen vigor, as indicated by pollen viability, pollen tube growth rates, and multiple pollen tube germinations, may influence blueberry growers' success in optimizing the beneficial effects of cross-pollination on fruit development.
Importance of `Blue' Photon Levels for Lettuce Seedlings Grown under Red-light-emitting Diodes
Authors: Hoenecke M.E. , Bula R.J. , Tibbitts T.W.
Published: February 2019

Light-emitting diodes (LEDs) with high-intensity output are being studied as a photosynthetic light source for plants. High-output LEDs have peak emission at ≈660 nm concentrated in a waveband of ±30 nm. Lettuce (Lactuca sativa `Grand Rapids') seedlings developed extended hypocotyls and elongated cotyledons when grown under these LEDs as a sole source of irradiance. This extension and elongation was prevented when the red LED radiation was supplemented with more than 15 μmol·m-2·s-1 of 400- to 500-nm photons from blue fluorescent lamps. Blue radiation effects were independent of the photon level of the red radiation.
Evaluation of Melon Germplasm for Resistance to Downy Mildew
Authors: Thomas Claude E. , Jourdain E.L.
Published: February 2019

Field evaluations for resistance against downy mildew, incited by Pseudoperonospora cubensis [(Berk. and Cart.) Rostow], were conducted on 942 U.S. Plant Introductions (PI) of Cucumis melo L. (melon). A disease index (DI) was calculated for each entry. Based on DI, PI 124112 was highly resistant (DI = 3.7), and PIs 124111, 122847, 124210, 145594, and 165525 were resistant (DI = 3.0, 2.8, 2.6, 2.7, and 2.5, respectively). PIs 124111 and 124112 had one or more plants that exhibited a highly resistant reaction type (RT 4). Resistant (RT 3) plants were identified in 31 accessions, and 49 accessions bad moderately resistant (RT 2) plants.
A Method for Extracting Intact RNA from Fruits Rich in Polysaccharides using Ripe Mango Mesocarp
Authors: López-Gómez R. , Gómez-Lim M.A.
Published: February 2019

A rapid and simple procedure is described for efficiently extracting intact RNA from mango (Mangifera indica L. cv. Manila) mesocarp, a tissue rich in polysaccharides. The RNA can be used for in vitro translation, northern blots, and cDNA synthesis. This method is applicable to other fleshy fruits rich in polysaccharides.