bluuebunny/crossref_metadata_2025 huggingface dataset:
The Role of Abscisic Acid in Heat Stress-induced Secondary Dormancy in Apple Seeds
Authors: Ozga Jocelyn A. , Dennis F.G.
Published: February 2019

Exposure of stratified apple (Malus domestics Borkh. cv. Golden Delicious) seeds to 30C induces secondary dormancy. To determine if an increase in abscisic acid (ABA) content was associated with the loss in germination capacity, stratified seeds (3,- 6, or 9 weeks at 5C) were held at 30C for 0, 3, or 6 days. Stratification at 5C either had no effect or increased ABA content in embryonic axes, cotyledons, and seed coats. Exposure to 30C after stratification either did not affect or decreased ABA content of embryonic axes and seed coats; in contrast, cotyledonary ABA was increased. Seed coats, cotyledons, and embryonic axes stratified for 3, 6, or 9 weeks at 20C contained the same or higher levels of ABA in comparison with nonstratified seeds or seeds stratified at SC. Changes in ABA levels were not consistently correlated with changes in germination capacity during stratification or after exposure to 30C. These data suggest that changes in ABA are not related to changes in dormancy. Chemical names used: abscisic acid (ABA); butylated hydroxy-toluene (BHT); n-(trichloromethyl) thio-4-cyclohexene-1,2-dicarboximide(Captan).
Simplified Method of Volatile Leaf Oil Analysis for Identification of Citrus Cultivars
Authors: Bade Jacob B. , Gmitter Frederick G. , Bowman Kim D.
Published: February 2019

Volatile oils were extracted from aqueous leaf suspensions of sweet orange [Citrus sinensis (L.) Osb.] cultivars Hamlin, Navel, and Valencia and grapefruit (Citrus paradisi Macf.) cultivars Marsh and Ray Ruby. Pressurized air was used as the sparging gas, and volatile oils were collected in a C-18 cartridge. Gas-liquid chromatography was used to separate and quantify 17 volatile components. Significant quantitative differences for individual components made it possible to distinguish sweet orange from grapefruit (four components), `Marsh' from `Ray Ruby' grapefruit (two components), `Hamlin' from `Valencia' or `Navel' orange (six components), and `Valencia' from `Navel' (three components). The simplicity and sensitivity of the procedure suggest potential use for Citrus taxonomic, genetic, and breeding research.
Variation in Growth, Spur Density, and Yield of `MacSpur McIntosh'
Authors: Embree C.G. , McRae K.B. , Estabrooks E.N. , Pratt C.
Published: February 2019

Vegetative and fruiting characteristics were measured for a spur mutant of `McIntosh' apple (Malus × domestics Borkh.). Nine-year-old `MacSpur' trees in an orchard in New Brunswick, Canada, were grouped according to three degrees of spurriness. Reduced terminal growth, fewer limbs per tree, more flowering spurs per unit length of 2- and 3-year-old wood, less yield, and lower yield efficiency were associated with the highest degree of spurriness. The variability suggests that `MacSpur' may be an unstable periclinal chimera.
Growth and Nutritional Responses of Nine Grape Cultivars to Low Soil pH
Authors: Himelrick David G.
Published: February 2019

Nine grape cultivars (Vitis vinifera L., V. labruscana Bailey, and French-American hybrids) were evaluated in pot culture for their tolerance to strongly acid (pH 4.8) and slightly acid (pH 6.7) soil. Differences in cultivar tolerance to the strongly acid soil included a reduction in shoot and root dry weights and root volume. Based on root development, the most tolerant cultivars to the strongly acid soil were the V. labruscana cultivars Concord and Catawba and the V. riparia × V. berlandieri rootstock cultivar SO 4. The least tolerant vines were the two V. vinifera cultivars White Riesling and Chardonnay and the interspecific hybrid `Aurore'. No consistent treatment effects were found in foliar N, K, or B levels, but P and Ca were higher and Mg, Fe, Cu, and Zn lower in plants grown in the very acid soil.
Influence of Paclobutrazol on Growth and Flowering of Rhododendron `Sir Robert Peel'
Authors: Wilkinson R.I. , Richards D.
Published: February 2019

Shoot extension of Rhododendron `Sir Robert Peel' was reduced, but flowering was more precocious after treatment of plants with paclobutrazol. All of the drench rates tested (0.05 to 0.4 g a.i./pot) proved excessive and resulted in prolonged shoot growth reduction but greatly increased the number of flowers. However, flowers produced at the higher drench rates were grossly malformed and unacceptable. Foliar spray treatments (250 to 2000 mg a.i./liter) were less inhibitory than drenches, and a single spray of 500 mg·liter-1 was considered an appropriate commercial application rate. Paclobutrazol application could thus prove to be a useful technique in producing compact flowering plants of Rhododendron hybrids for improved retail sales. Chemical name used: β-[(4∼chlorophenyl) methyl] (1,1-dimethylethl)-1H-l,2,4-triazole-l-ethano1 (paclobutrazol, ICI-PP333).
Allelopathic Effects of Alfalfa Plant Residues on Emergence and Growth of Cucumber Seedlings
Authors: Ells James E. , McSay Ann E.
Published: February 2019

Growth chamber tests demonstrated that alfalfa (Medicago sativa L.) residue is toxic to cucumber (Cucumis sativus L.) seed germination and seedling growth. Ground alfalfa roots at 0.5% (w/w, dry weight) inhibited germination when added to the growing medium. Alfalfa roots at 0.5% were also toxic to pregerminated cucumber seed. However, cucumber seedlings grew normally if this same medium was watered and incubated for >1 day before planting. Alfalfa particle size in media influenced cucumber performance, with the intermediate size (1 to 2 mm) being lethal to cucumbers.
Root Growth of Southern Magnolia Following Exposure to High Root-zone Temperatures
Authors: Martin Chris A. , Ingram Dewayne L.
Published: February 2019

Root growth of southern magnolia (Magnolia grandiflora Hort. `St. Mary') was studied for 16 weeks after an 8-week exposure to 30, 34, 38, or 42 ± 0.8C root-zone temperature (RZT) treatments applied for 6 hours daily. Immediately after RZT treatments, total root length of trees responded negatively to increased RZT in a quadratic pattern and the shoot and root dry weight of trees was similar. However, 8 and 16 weeks after RZT treatments, total root length responded linearly in a negative pattern to increased RZT, and shoot and root dry weight responded negatively to increased RZT in a linear and quadratic pattern, respectively. Root dry weight of trees exposed to 42C RZT treatment was 29% and 48% less than 38 and 34C RZT treatments, respectively, at week 8. By week 16, root dry weight as a function of RZT had changed such that the 42C RZT was 43% and 47% less than 38 and 34C RZT, respectively. Differences in root growth patterns between weeks 8 and 16 suggest that trees were able to overcome the detrimental effects of the 38C treatment, whereas growth suppression by the 42C treatment was still evident after 16 weeks.
Quality Changes During Storage and Ripening of `Tommy Atkins' Mangos Treated with Heated Forced Air
Authors: Miller W.R. , McDonald R.E. , Sharp J.L.
Published: February 2019

Freshly harvested mangos (Mangifera indica L.) treated with forced air at 51.5C for 125 minutes then stored for 1, 2, or 3 weeks at 12C, followed by 21C until soft-ripe, were compared with nontreated fruit for quality changes. Treated fruit lost 1.0% more fresh weight than nontreated fruit and deveoped trace amounts of peel pitting. Total soluble solids concentrations for treated and nontreated fruit were similar (≈q3%), as was peel color at the soft-ripe stage. Treated fruit generally reached the soft-ripe stage ≈q day earlier than nontreated fruit regardless of storage duration and had a lower incidence and severity of stem-end rot and anthracnose. The trace of pitting on treated fruit likely will not influence consumer acceptance.
Occurrence and Inheritance of Resistance to Eastern Filbert Blight in `Gasaway' Hazelnut
Authors: Mehlenbacher Shawn A. , Thompson Maxine M. , Cameron H. Ronald
Published: February 2019

`Gasaway' hazelnut (Corylus avellana L.) is highly resistant to eastern filbert blight caused by Anisogramma anomala (Peck) E. Muller. Progeny produced from controlled crosses of `Gasaway' with five susceptible genotypes and open pollination in a `DuChilly' orchard were planted in a diseased orchard and rated for symptom expression for 9 to 10 years. All progeny were found to segregate 50% resistant: 50% susceptible, indicating that `Gasaway' is heterozygous for a single dominant resistance gene.
INFLUENCE OF SOIL FUMIGANTS AND A NEMATICIDE ON GROWTH AND YIELD OF `MCINTOSH' APPLE TREES ON VARIOUS ROOTSTOCKS
Authors: Costante Joseph F. , Autio Wesley R. , Berkett Lorraine P.
Published: February 2019

`Rogers Red McIntosh' apple (Malus domestica Borkh.) trees on MM. 111, MM. 106, M.7a, or M.26 were planted in 1984 on an old orchard site, diagnosed with an apple replant disease (ARD) problem. Soil treatments included Telone c-17, Vorlex, Nemacur 3, or not treated. After six years, tree performance problems usually associated with severe ARD did not develop. Lesion nematode [Pratylenchus penetrans (Cobb) Filipjev and Schuurmans-Stekhoven] populations feeding within or on the surface of roots were not affected by nematicide treatments nor rootstocks, even though slightly damaging levels were found in 1986. At the end of the sixth growing season, trunk cross-sectional areas were similar for trees in treated and in untreated soils. Trees on MM. 111 and MM. 106 were the largest, and those on M.26 were the smallest. Cumulative yield was not influenced by soil treatments, but trees on MM. 111 produced the greatest cumulative yields, whereas trees on M.26 were the most yield efficient.
`OKA' STRAWBERRY
Authors: Khanizadeh Shahrokh , Lareau Michel , Buszard Buszard
Published: February 2019

`Oka' is a mid-season, high yielding June-bearing strawberry cultivar with excellent productivity, good fruit color, flavor and firmness. It is recommended for fesh market and pick your own for the Southern Québec region. `Oka' plants are of medium size, and vigor with five to seven inflorescences per mother plant. They can tolerate winter temperatures of -25 C. Inflorescences are held erect on medium to long peduncles during bloom, and become semi-erect as fruit mature. Fruits are large, wedge shape and the calyces are semi-reflexed. Skin is moderately shiny, light red at full maturity, and the flesh is light red. Fruit flavor is similar to `Bounty', `Chambly', `Glooscap' and `Sparkle'. Fruits are medium firm to firm, and can not be decapped as easily as `Bounty', `Chambly' or `Glooscap'. More than 50% of harvested fruit have long pedicels. Percent juice loss after thawing does not differ significantly from other popular cultivars. `Oka' has outyielded `Bounty', `Redcoat' and `Sparkle' at L'Acadie and `Bounty', `Glooscap', and `Veestar' in New Brunswick. Plants can tolerate the herbicide terbacil. No symptoms of powdery mildew or leaf scorch were observed during the course of its evaluation. However some symptoms of leaf spot were observed late in the season before the onset of dormancy. Preliminary studies show that `Oka' is resistant to races 2, 4, 5, 8, 9 and 10 of P. fragariae.
NATURAL ECOSYSTEMS AS TOOLS FOR TEACHING LANDSCAPE DESIGN
Authors: Smith W. Gary
Published: February 2019

Native plant ecosystems, such as meadows and forests, demonstrate how plant communities are physically organized in response to a variety of natural factors and environmental processes. By visiting native ecosystems and diagramming the spatial patterns of naturally evolving plant communities, landscape design students quickly gain confidence about the variety of spaces they can create with plants. In addition, they develop an understanding that the physical organization of plants can have ecological meaning, deeper than simple utility, function, or decoration.
ALTERNATIVE ORCHARD GROUNDCOVER MANAGEMENT SYSTEMS INFLUENCE EARLY APPLE YIELDS AND MORTALITY.
Authors: Merwin Ian
Published: February 2019

Eight groundcover management systems (GMS) have been studied since 1986 in an apple orchard replant site. Tree-row GMS consisted of post-emergence “killed sods” and pre-emergence herbicide strips, a crownvetch “living mulch,” hay-straw mulch, clean cultivation, a close-mowed sod, and an unmowed but chemically growth-regulated sodgrass. Trees initially grew best in the straw-mulch treatment, but nearly 40% have succumbed to Phytophthora crown rot since 1988, apparently due to excessive soil moisture. Meadow vole populations have been higher, and vole injury to lower trunks has been more frequent and severe on trees in crownvetch and straw-mulch GMS, despite routine rodenticide baiting. Cumulative yields per tree have been highest in straw-mulched trees, but yields per acre have been much lower, because of the increased tree mortality in this treatment.
THE USE OF INTERPLANTED COVER CROPS FOR PEST MANAGEMENT IN STRAWBERRIES
Authors: Pritts Marvin P.
Published: February 2019

Non-chemical methods for weed management are becoming important as fewer herbicides are labelled for use and as the market demands pesticide-free produce. We have studied the use of interplanted cover crops in strawberry plantings as an alternative/supplement to chemical weed management. Several different cover crops (tall fescue, marigold and sudangrass) were seeded between rows of newly planted strawberries in late June as runnering was commencing. An additional seeding of sudangrass was made in late July. For comparison, untreated plots and diphenamid treated plots were included in the experimental design. Measurements were taken throughout the season of soil moisture, light levels, crop nutrient concentrations, nematode numbers in soil and crop roots, runner biomass, and weed composition and biomass. Cover crops were incorporated in late fall and the planting was mulched. The following spring, crop nutrient concentrations, nematode numbers in soil and crop roots, weed composition and biomass, yield, individual fruit size, and aboveground strawberry biomass was assessed. The marigolds were too competitive for moisture to be an effective companion cover crop. The early planting of sudangrass was too tall, and fescue was too competitive for nutrients. The untreated plots contained many more weeds than other treatments, nematode levels were higher in the strawberry roots in these plots, and harvesting fruit was very difficult. The late seeding of sudangrass, however, provided significant weed control while not reducing yield relative to herbicide-treated plots.
PESTICIDE RESIDUES ON FRESH AND PROCESSED VEGETABLES
Authors: Michaud Marie-Hélène , Makhlouf Joseph , Tremblay Nicolas , Gosselin André
Published: February 2019

A research project was undertaken in 1990 with the objective of improving both quality and productivity of peas, beans and sweet corn grown and processed in Quebec (Canada). It was conducted with the technical and financial help of five proccessing companies. Cultivar trials were undertaken as part of this project together with an evaluation of commercial practices in the areas of pest control, fertilization and crop management. Samples of fresh and processed products were analysed for nutritional quality and pesticide residues. During this presentation we will show preliminary results of the pesticide residue analyses and will compare fresh and processed products. So far, determination of dimethoate, trifluralin and bentazone (peas), azinphosmethyl and permetrin (beans) and cypermetrin (sweet corn) showed no concentration exceeding the Canadian norm (<0, 1mg/kg), with the exception of a bean field with azinphosmethyl residues. Canning and freezing operations greatly reduced pesticide residues so that all processed samples tested below detectable levels.
TRANSPLANTING TO LARGE CONTAINERS TWO TREE SPECIES PRODUCED IN GROW BAGS AND BY TRADITIONAL FIELD PRODUCTION METHODS
Authors: Tilt Ken , Gilliam Charles H. , Olive John W.
Published: February 2019

Lagerstroemia × `Natchez' and Quercus virginiana were planted into a sandy loam soil in grow bags and by traditional field planting methods. After 2 years in the field, 1 sample from each of 6 replications was dug from the field in March. Root and top growth were measured. Half the remaining plants were dug and transplanted into 76 liter containers for 3 months. Growth indices were measured at this time. The remaining trees in the field were dug in July and handled similarly. Data from live oak trees showed increased height in trees produced by traditional field planting methods. No differences between planting methods were found in any other growth indices for the two species. Both crapemyrtle and live oak trees transplanted from traditional field plantings in March had greater height than trees transplanted from grow bags. However, no differences were detected for top weight, caliper or root ratings. July transplanted crapemyrtles showed no differences in any of the growth indices. Live oaks transplanted in July from traditional field plantings to containers all died with no additional growth. Grow bag transplanted oaks survived and continued to grow.
HERBICIDE USE IN PROPAGATION
Authors: Gilliam C. H. , Eakes D. J. , Olive J. W. , Thetford M.
Published: February 2019

Two experiments were conducted to evaluate commonly used granular preemergence herbicides applied prior to the sticking of cuttings in propagation. Rooting percentage of the three cultivars, `Trouper' azalea, `Hino-Crimson' azalea, and `August Beauty' gardenia, was not affected in experiment 1. However, all three species exhibited some reduction in root quality or root length with all herbicides. In general, the herbicides with the least suppression were: Ronstar, Southern WeedGrass Control, OH-2, Snapshot 2.5 TG, and Rout. The second experiment with `August Beauty' gardenia evaluated the effect of cuttings depth in overcoming the negative herbicide effects on root development. The results were similar to those obtained in experiment 1.
EARLY PERFORMANCE OF `REDHAVEN' PEACH ON 10 PRUNUS ROOTSTOCKS
Authors: Rom Curt R. , Rom R.C. , Bourne R.
Published: February 2019

`Redhaven' trees on 10 rootstocks planted in 1984 were annually evaluated for growth and cropping as part of the NC-140 national cooperative rootstock troial. All trees on Citation have died, 60 % of trees on GF-43 have died and only a single tree of Lovell, Halford, and GF-677 have died. Trees on Damas GF-1869 and GF-655.2 had significantly more root suckers than other trees. Redhaven own-root, Halford and GF-677 were largest in height, spread, canopy volume or TCSA while the smallest trees were GF-43, Damas, and GF-655.2. Damas, GF-43 and GF-655.2 bloomed 3-4 days before trees on Lovell. Fruit on Redhaven own-root matured 4 days before fruit on Lovell while fruit on Halford, GF-677 and GF-43 ripened 2 days later than Lovell. Trees on Halford had the highest annual yield and accumulated yield while GF-655.2, Damas and GF-43 had the lowest yields. Redhaven own-root and Halford had the highest yield efficiencies (kg/cm2TCSA). Trees on Lovell consistently produced the largest individual fruit size.
INFLUENCE OF SEVERAL ROW COVERS ON YIELD OF BROCCOLI AND CABBAGE IN SOUTHEAST MISSOURI
Authors: Wilson Mack A. , Aide Michael T. , Khan Victor A.
Published: February 2019

Four row covers were evaluated on fall production of `Packman' broccoli and `Gourmet' cabbage at Cape Girardeau, Missouri. Row covers used were spunbonded polyester, insolar and clear slitted polyethylene and VisPore. The mean afternoon soil temperature for row covers were higher than the bare soil control. There were no significant differences among treatments with respect to head size, total numbers and yield of marketable broccoli. The number of broccoli heads per thousand between the bare soil control vs. row cover treatments were significantly different. Data for number of broccoli heads per thousand and marketable yield (Kg/Ha) were significant among row covers. Marketable yield (Kg/Ha) was significant among row covers for `Gourmet' cabbage.
OPTIMUM SPACING AND HARVEST TIME FOR `INTERMEDIATE LEAF' HYBRID PICKLING CUCUMBERS FOR ONCE-OVER MECHANICAL HARVEST.
Authors: Cook Kevin L. , Pike Leonard M.
Published: February 2019

An `intermediate leaf' hybrid pickling cucumber (TAMU 884304 X ARK H-19 `little leaf') was direct-seeded at four plant densities (94,570; 48,440; 32,290; 25,375 plants/ha) using four within-row spacings (15, 30, 45, 60cm) at two locations and two seasons. Optimum yield based on marketable fruit number, grade distribution and fruit quality occurred with 94,570 plants/ha. Optimum harvest time depended on location and season. Delayed harvest times were also evaluated. Harvests with fruit >5.1cm in diameter had severely reduced brining quality. Fruit did not enlarge or enlarged slowly to oversize. This resulted in a mixture of fruit ages within the largest marketable fruit grades. It is recommended that `little leaf' lines and their hybrids such as `intermediate leaf' be harvested when fruit 3.8 to 5.1cm in diameter appear and before oversize fruit are produced. Spacing did not significantly effect length/diameter ratio(LDR) but LDR was significantly greater for delayed harvests.
SWEET CORN YIELD AND INSECT DAMAGE AS AFFECTED BY COVER CROPS AND NITROGEN
Authors: Roberts Warren , Cartwright Bob
Published: February 2019

The effects of cover crops and nitrogen on yield and insect damage of sweet corn were examined. In 1989, sweet corn was grown in bare soil plots, plots covered with rye (Secale cereale), and plots covered with hairy vetch (Vicia villosa). In 1990 a black plastic mulch treatment was substituted for the hairy vetch treatment. Each soil cover was fertilized with 45, 90, 134, or 179 kg/ha nitrogen (N) in 1989, and 34, 101, 168, 235, or 302 kg/ha N in 1990. Covers were planted in the fall, followed by sweet corn the following spring. There was no mowing or tilling of the cover crops.

Corn yields were lower each year in the rye covered plots. There were more corn earworms on the rye covered plots. Corn pollination was poorer on the rye covered plots, but responded positively to increasing rates of N.
GENETIC VARIABILITY OF LEAF AND POLLEN PHOSPHOGLUCOSE ISOMERASE IN IPOMOEA BATATAS AND I. TRIFIDA
Authors: Zhu Zhigiang , Thompson Paul G.
Published: February 2019

The polymorphisms of phosphoglucose isomerase (PGI) in sweetpotato and I. trifida were examined. Horizontal starch gel electrophoresis was used to analyze leaf and pollen tissue of parents and progenies of 10 crosses. Analyses revealed that PGI was a dimeric enzyme system controlled by 5 loci. The segregation ratios did not suggest that PGI was a duplicate system and therefore did not indicate hexaploidy. Only 2 loci appeared to be present in I. trifida. No observed band was related to different ploidy levels in I. batatas and I. trifida. No linkage was identified among the loci.
GUAR BEAN PRODUCTION IN GEORGIA
Authors: Bhardwai Harbans , Eitenmiller Ron
Published: February 2019

Guar or cluster bean (Cyamopsis tetragonoloba (L.) Taubert), a leguminous plant, is grown in many parts of the world for consumption as green beans. However, information on green bean yield and their nutritional quality is lacking. Our objectives were to determine yield potential, optimum harvesting time, and nutritional quality of green guar beans. We planted 10 guar varieties in a RCBD with 4 replications on 1 June 1990 at Fort Valley, Georgia. The guar bean production was recorded at 55, 70, 85, and 100 days after planting (DAP). Significant variation for bean yield existed among genotypes. The bean yield (kg ha-1) varied from 9549 (Kinman) to 1629 (HG-75), at 85 DAP. The highest yield at 100 DAP was recorded for Lewis. The ideal harvesting time, based on degree of yellowness and bean texture, for Durga Jay, Esser, Hall, SPS-119, and Lewis seemed to be 100-115 DAP whereas the beans of Brooks, HG-75, HSB-130, Kinman, and Santa Cruz became tougher and yellow by 100 DAP. A comparison with published results of snap beans and edible-pod peas indicated that green guar beans contained greater amounts of protein, total carbohydrates, vitamin C, calcium, iron, manganese, phosphorus, potassium, and sodium. These results indicate that green guar beans can be a potential alternate source of income for farmers in Georgia and other states.
MANAGEMENT OF SOIL INSECTS AND THEIR DAMAGE TO SWEETPOTATO THROUGH THE USE OF INSECT RESISTANT CULTIVARS, INSECTICIDE AND BIOLOGICAL CONTROL.
Authors: Schalk J. M. , Jones A. , Dukes P. D. , Seal D. R.
Published: February 2019

The test involved the use of a control (untreated), an entomopathogenic nematode (Steinernema carpocapsae), a granular insecticide (Dyfonate 2.24 Kg ai/ha) in combination with 7 sweetpotato cultivars having varying levels of resistance and susceptibility to soil insect damage. The parasite was applied three times at monthly intervals (67/cm2). The parasite or insecticide did not reduce root injury by soil insects as compared to the control (untreated). Wireworms, Diabrotica sp. and Systena sp. damage in the resistant cultivars Regal, Southern Delite, Excel and Resisto was less than for the susceptible cultivars (SC–1149-19, Jewel and Centennial). Sweetpotato flea beetle resistance was observed for all cultivars except SC–1149-19 which was susceptible. In this test resistant cultivars were more effective in reducing soil insect damage than the biological or chemical control methods.
MANAGEMENT OF SOIL INSECTS AND THEIR DAMAGE TO SWEETPOTATO THROUGH THE USE OF INSECT RESISTANT CULTIVARS, INSECTICIDE AND BIOLOGICAL CONTROL.
Authors: Schalk J. M. , Jones A. , Dukes P. D. , Seal D. R.
Published: February 2019

The test involved the use of a control (untreated), an entomopathogenic nematode (Steinernema carpocapsae), a granular insecticide (Dyfonate 2.24 Kg ai/ha) in combination with 7 sweetpotato cultivars having varying levels of resistance and susceptibility to soil insect damage. The parasite was applied three times at monthly intervals (67/cm2). The parasite or insecticide did not reduce root injury by soil insects as compared to the control (untreated). Wireworm, Diabrotica and Systena damage in the resistant cultivars Regal, Southern Delite, Excel and Resisto was less than for the susceptible cultvars (SC–1149-19, Jewel and Centennial). Sweetpotato flea beetle resistance was observed for all cultivars except SC–1149-19 which was susceptible. In this test resistant cultivars were more effective in reducing soil insect damage than the biological or chemical control methods.
MAYPOP (PASSIFLORA INCARNATA L.) AND PASSION FRUIT (PASSIFLORA EDULIS) COMPARED
Authors: Arjona Harvey E. , Matta Frank B. , Garner James O.
Published: February 2019

Fruit growth and composition of commercial passion fruit types and maypop were compared. Fruit growth (diameter) of purple passion fruit (Passiflora edulis Sims.) and maypop (P. incarnata L.) followed a sigmoidal growth curve. Passion fruit were larger than both greenhouse-grown and wild maypop fruit. Wild maypop produced larger fruit compared to greenhouse grown maypop. Yellow passion fruit had the lowest percentage pulp and the highest soluble solids. Greenhouse-grown maypop had the lowest soluble solids. Purple and yellow passion fruit had lower juice pH than maypop. Wild maypop fruit had the highest sucrose and purple passion fruit had the lowest. Yellow and purple passion fruit juice had higher fructose and glucose than did maypop juice.
COWPEA VIRUSES, INDIGENOUS AND EXOTIC, AND UNIQUE MECHANISMS BY WHICH THEY ARE DISSEMINATED AND INADVERTENTLY INTRODUCED
Authors: Hampton Richard
Published: February 2019

Vectors with specific vector-virus relationships (e.g., aphid, beetle, thrip, nematode) commonly cause short-range dissemination of cowpea viruses. However, viruses that are seed-borne in cowpea can be disseminated around the world in a single year through seed shipments. Likewise, increased world emphasis on germplasm collection and exchange, for development of improved crop cultivars, increases the risk of disseminating seed-borne viruses in germplasm. Seed-borne cowpea viruses that are not reported in the U.S.A., but are apt to occur in Vigna unguiculata from world centers of cowpea origin include COWPEA APHID-BORNE MOSAIC, COWPEA MILD MOTTLE, COWPEA MOSAIC, and COWPEA MOTTLE VIRUSES. All of these viruses were detected by ELISA serology in V. unguiculata seedlots processed as potential germplasm introductions, in collaboration with the government of Denmark. Germplasm-borne viruses, once introduced into breeding programs, may be seed-transmitted directly into breeding progenies, along with genes derived from the germplasm source. Such viruses also may be spread by insect vectors to other breeding lines, and could cause disease outbreaks to nearby commercial cowpea crops.
VIRUSES SEED-BORNE IN COWPEA: SIGNIFICANCE FOR COWPEA BREEDING PROGRAMS AND PRODUCTION
Authors: Bashir Muhammad , Hampton Richard
Published: February 2019

By ELISA serology, we have detected and identified the following seed-borne viruses in Vigna unguiculata seedlots, processed cooperatively with the government of Denmark as potential germplasm introductions: BLACKEYE COWPEA MOSAIC, COWPEA APHID-BORNE MOSAIC, COWPEA MILD MOTTLE, COWPEA MOSAIC, COWPEA MOTTLE, COWPEA SEVERE MOSAIC, CUCUMBER MOSAIC, and SOUTHERN BEAN MOSAIC VIRUSES. Twenty-three of 155 seedlots from 10 old-world countries were found to contain one or more of these viruses. TOBACCO RINGSPOT and URD BEAN LEAF CRINKLE VIRUSES are known to be seed-borne 1n cowpea, but were not included in assays. At least six other cowpea-crop-damaging viruses, as yet inadequately characterized, are also reportedly seed-borne in cowpea in India and countries of west Africa. We are currently characterizing viruses in Vigna pre-introductions and selected germplasm accessions, with emphasis on seed-borne potyviruses. Comparisons among B1CMV and CAMV isolates, for which cowpea sources of genetic resistance have been identified, revealed a wide range of isolate pathogenicity for both viruses.
EFFECTS OF SURFACE MOISTURE AND COLONIZATION BY INA BACTERIA ON FROST DAMAGE TO TOMATO SEEDLINGS
Authors: Drown Glenn , Anderson Jeffrey
Published: February 2019

Natural colonization of tomato transplants (Lycopersicon esculentum Mill. `Supersonic') by ice nucleation active (INA) bacteria was monitored during a warm, dry period in the spring and during a rainy period in the fall. Populations of INA bacteria and freezing temperatures were determined for seedlings on days 1 to 5, 7, 9, 12, and 15 after transplanting. During the spring experiment, plant freezing temperatures ranged from -6.4C to -3.6C. INA bacteria were detected from day 1 after transplant with populations ranging from 6 to 630 cells/g fresh wt. Most plants had detectable levels of INA bacteria after 3 days in the field, but some plants did not have detectable levels after 15 days. In the fall, populations of INA bacteria were similar to spring levels for the first week after transplant. Numbers of INA bacteria were higher and plant freezing temperatures warmer on days 9 through 15 in the fall compared with the same period in the spring.

Laboratory experiments were conducted using plants without INA bacteria. Seedlings with dry surfaces supercooled to lower temperatures than tomato plants with wet surfaces.
PLANTING DATE EFFECT ON PIGEONPEA DEVELOPMENT IN MID-MISSOURI
Authors: Marsh Lurline , Dkhili Mohsen
Published: February 2019

Determinate, photoperiod-insensitive genotypes of pigeonpea, (Cajanus cajan) have the potential for production in the short growing season of the temperature region. A field study was conducted to determine the effect of three planting dates on the growth and development of this crop in Missouri. Seeds of four genotypes, ICPL 87 Isolation (85k), ICPL 85010, ICPL 85024 and ICPL 8304 were planted at three planting dates in 1990, May 1, May 15 and May 31. Germination of the earliest planted seeds was low but increased in the later planted ones. The earlier the planting date the longer was the time to flowering, but the earlier was pod maturity. The earliest planted group flowered within 78-110 days after planting. The genotypes in this group produced the highest fresh pod weights of 330-730 g/plant and the latest planted ones produced the least. Pod length, the number of seeds per pod and weight of 100 seeds had ranges of 5.1-5.9 cm, 3-4 seeds and 17-23 g, respectively and were unaffected by planting dates.
THE INFLUENCE OF EXPLANT SOURCE AND CHILLING ON IN VITRO PROPAGATION OF HERBERTIA LAHUE
Authors: Carlisi-Dunlop Jacqueline , Wollard Dennis L.
Published: February 2019

Herbertia lahue is a rare native iris species of South Louisiana and is difficult to propagate. Seed and bulbs were evaluated as potential explants for micropropagating Herbertia lahue. Green and dry seeds of Herbertia were chilled at 8°C for 0, 3, 6 and 9 weeks on MS media containing 0.0, 4.9 and 9.8 μM BAP and 0.0, 5.4 and 10.7 μM NAA. Seeds cultured on 4.9 μM BAP plus 5.4 NAA, and 9.8 μM BAP plus 10.7 μM NAA produced healthy shoots with no roots. Cultures with no hormones produced shoots with roots. Germination appears to be a matter of time and not the effect of chilling, age of seed, nor hormones. Bulbs were scaled to 5 and 10 mm and placed on the above media with no chilling. Bulbs scaled to 10 mm resulted in a high rate of contamination. Scaling to a 5 mm explant produced fewer contaminated cultures. Decontaminated bulbs produced healthy shoots across all treatments.
THE EFFECT OF ULTRAVIOLET LIGHT ON CONTROLLING POSTHARVEST ROTS ON FRUITS
Authors: Stevens C. , Wilson C. L. , Lu J. Y. , Khan V. A. , Chalutz E. , Kabwe M. K. , Haung Z. , Droby S. , Pusey L.
Published: February 2019

Low doses of ultraviolet light (254nm UV–C) irradiation reduced postharvest rots of pome, stone and citrus fruits. Brown rot (Monilinia fructicola) of `Elberta' and `Loring' peaches was significantly reduced by UV–C. Alternaria rot (Alternaria spp.) and bitter rot (Colletotrichum spp.) the principal storage rots of `Golden Delicious apples showed significant reduction following UV–C treatment. Further application of UV–C was effective in controlling green mold rot (Penicillium digitatum) of `Dancy' Tangerines and `Marsh Seedless' grapefruits, stem end rot (Alternaria citri), as well as sour rot (Geotrichum candidum) of `Dancy' tangerines after irradiation.
PERFORMANCE OF `REDGLOBE' PEACH ON FIVE R00TST0CKS
Authors: Pee K.C. , Johnson C.E.
Published: February 2019

Trunk diameter, yield, root sprout production, and tree mortality of `Redglobe' peach were evaluated over a 14 year period on 5 rootstocks; `Lovell', `Halford', `Nemaguard', `Bailey', and `Siberian C'. Trunk diameter in year 14 was not different for trees on `Lovell' and `Halford', with diameters on 23.7 and 23.5 cm respectively, as compared to 93 and 45 kg on `Halford'. These were not significantly different from each other. Both `Lovell' and `Halford' produced 1.8 root sprouts per tree or less both years. Trunk diameter on `Nemaguard', `Bailey', and `Siberian C' was different from `Lovell' and `Halford'. Yields on `Nemaguard', `Bailey', and `Siberian C' were 92, 88, and 41 kg respectively, in year 12, with trees on `Siberian C' being different from the other 4 rootstocks. Yields in year 14 were 60 kg on `Nemaguard', 50 kg on `Bailey', and 28 kg on `Siberian C'. Root sprout averages per tree on `Nemaguard' were 1.6 and 6.7 in years 8 and 14 while `Bailey' averaged 1.1 and 7.7. Root sprouts on `Siberian C' were low in year 8, but increased in year 14 to 15.1 per tree. Tree mortality on `Siberian C' was 44% by year 14.
PREPLANT SOIL PREPARATION METHODS INFLUENCE PRODUCTIVITY OF `HARVESTER' PEACH TREES
Authors: Payne J.T. , Johnson Charles E.
Published: February 2019

Influence on productivity of `Harvester' peach trees to three methods of preplant soil preparation were studied for five years. The three methods were as follows: 1) a backhoe was used to prepare the soil, 2) a turn-plow, and 3) no preparation. Trunk yield data were taken after the first three growing seasons. There were no significant treatment differences for yield at the .05 level of probability. Trends show an increase in yield using the turn-plow and the backhoe method showed better early tree growth, but by the fifth year, there were no apparent differences.
WATER QUALITY AFFECTS CALCIUM AND MAGNESIUM REQUIREMENTS FOR AZALEA GROWING MEDIUM
Authors: Bush E.W. , Wall D.A. , Robbins M.L.
Published: February 2019

Calcium and magnesium medium requirements were investigated for the production of container-grown `Formosa' azalea irrigated with filtered and unfiltered deep well water. Four inch `Formosa' azalea plants were planted into 3.8 liter containers filled with an amended 4:1(v,v) pinebark:sand growing medium. Calcium and magnesium treatments were supplied by either dolomitic lime or gypsum + epsom salt at three rates. Plants irrigated with good quality water produced excellent quality plants regardless of Ca/Mg treatment. Alkaline well water containing moderate sodium levels inhibited azalea root growth. Medium amended with gypsum + epsom salt produced significantly better quality plants than did medium with dolomitic lime during 157 days of deep well irrigation. Medium pH and Na levels were significantly higher in the control treatment than in the filtered well water treatment. Growth effects of calcium and magnesium treatments were dependent upon water quality and time length of treatment.
A GENETIC STUDY OF RIND COLOR PATTERNS IN WATERMELON
Authors: Johnson Charles E. , Buckley Blair
Published: February 2019

Inheritance of dark green stripe and light green rind color in watermelon was investigated. Controlled crosses were made between watermelon cultivars: `Louisiana Sweet'-light green rind with dark green stripe; `Calhoun Sweet'-dark green rind without stripes; and `Charleston Gray' and `Calhoun Gray' both having light green rind without stripes. Plants of parental, F1, F2, and BC lines were classified as to rind color and presence or absence of stripe. All F1 progenies produced only striped fruit. Chi Square analysis of F2 and BC generations corresponded to 3:1 and 1:1 ratios respectively, for stripe:no stripe, indicating dark green stripe was controlled by one dominant gene. The cross `Louisiana Sweet' × `Calhoun Sweet',(light green × dark green rind color), resulted in F1 and F2 progeny having only dark green rind fruit, indicating obvious dominance for dark green rind color. Segregation in BC populations indicated a single dominant gene for dark green rind color; however, lack of segregation in the F2 suggests additional factors may be involved.
PLANT GROWTH AND RESIDUE DECOMPOSITION COMPONENT OF WEPP - WATER EROSION PREDICTION PROJECT FOR FRUIT AND VEGETABLES.
Authors: Cole-Crosby Iris , Huam Liang , Harness Jesse , Igbokwe Patrick , Tiwari Suresh , Vadhwa Om P.
Published: February 2019

Plant growth and residue decomposition values are needed by the Soil Conservation Service for developing data bases for selected fruit and vegetable crops. These data bases will be used for predicting soil loss using improved erosion prediction technology. The plant growth parameters under investigation are canopy cover leaf area index, plant height plant weight, root weight, stem diameter and vegetative dry matter. The climatic parameter are daily base temperature rainfall and growing degree days. The following is a list of the residue decomposition parameter: 1. Residue weight and harvest 2. Initial carbon-nitrogen ratio, and 3. Percent residue cover at harvest. The results are being used in the WEPP model to predict soil erosion. Data collection afor these parameters start 15 days after planting for vegetables and continue at 7 day intervals through maturity.
THE EFFECTS OF DIURNAL LIGHT ON PHOTOSYNTHSIS AND GROWTH OF GREENHOUSE GROWN APPLE
Authors: Moran Renae E. , Rom. Curt
Published: February 2019

Greenhouse grown `Lawspur Rome'/M.111 trained to single shoots were given the following shade (73%) treatments: 1) sun-all-day (control), 2) shade in the morning (am-shade), 3) shade in the afternoon (pm-shade) and 4) shade-all-day. All shade treatments increased shoot length and decreased dry weight/leaf area (DW/LA). Shade-all-day increased leaf no., LA/leaf and shoot dia. DW partitioning to leaves in shade-all-day was 19% greater than control and to roots was 34% less than control. Pn of am-shade did not increase in the afternoon when PFD was maximal. Saturated net photosynthesis (Pn) was 72% of control in am-shade, 84% of control in pm-shade and 62% in shade-all-day. Shade reduced Pn by 40% of control.
Turf Response to Urease Inhibitors and Cationic Materials Applied in Combination with Urea
Authors: Joo Young K. , Christians Nick E. , Bremner John M.
Published: February 2019

We evaluated the response of Kentucky bluegrass (Pea pratensis L.) turf to urea amended with the urease inhibitors PPD, NBPT, and ATS and with the cations K+ (KCl) and Mg+2 (MgCl2). Treatments for the 2-year field experiment included liquid urea applied monthly in June to Sept. 1985 and 1986 at 49 kg N/ha with PPD (1%, 2%, 3% by weight of applied N), NBPT (0.5%, 1%, 2%), ATS (5%, 15%, 25%), K+ (5%, 15%, 25%), and Mg+2 (5%, 15%, 25%). The NBPT was included only in the 1986 field study. The Mg+2 and K+ reduced foliar burn and increased turf quality during mid- and late Summer 1985 at the 5% rate, but clipping yield was not affected by any treatment. In 1986, under milder climatic conditions, PPD and NBPT increased clipping yield by 13.2% and 15.2%, respectively. At the 15% rate, ATS increased clipping yield by 15.1%, but, on average, PPD and NBPT were much more effective. Chemical names used: phenylphosphorodiamidate (PPD), N-(n -butyl) thiophosphoric triamide (NBPT), and ammonium thiosulfate (ATS).
Priming Improves High-temperature Germination of Pansy Seed
Authors: Carpenter William J. , Boucher Joseph F.
Published: February 2019

The optimum conditions for priming pansy (Viola × wittrockiana) seeds were in aerated osmotic solutions of polyethylene glycol 8000 (PEG 8000) at – 1.0 MPa for 7 days at 15C. Priming at – 0.8 MPa and 15C caused 8% to 26% of seeds to germinate during 4 to 13 days of priming. Increasing numbers of abnormal seedlings developed when priming was extended beyond 7 days. Final germination percentages were better in laboratory studies at 35C for primed (51%) than nonprimed (10%) seeds. Removal of the mucilage released by the seed with 240 g KOH or 170 g NaOH/liter for 15 or 30 seconds during priming did not affect total germination percentages, but did improve seed handling. Primed seed had higher, faster, and more uniform germination than nonprimed seeds after sowing in growing medium in plant growth chambers or greenhouses.
Calcium Nutrition and Cultivar Influence Incidence of Tipburn of Collard
Authors: Johnson Jon R.
Published: February 2019

The collard (Brassica oleracea, Acephala group) cultivar Vates was more susceptible than `Blue Max' to tipburn in sand-culture and field studies. Calcium concentrations in young leaves were similar for both cultivars. `Blue Max' appears to require a lower Ca concentration in young leaves than `Vates' for normal growth. In sand-culture studies, increasing the Ca level in nutrient solution to 3 mm or higher decreased tipburn in `Vates'. `Blue Max' did not develop tipburn regardless of Ca level. Increasing the Ca level in nutrient solution increased Ca concentration in young and old leaves for both cultivars. Soil application of CaSO4 or foliar application of Ca(NO3)2 or CaCl2 did not decrease occurrence of tipburn in Yates', presumably because these treatments did not increase Ca concentrations in young leaves.
Yield and Quality Responses of Garlic and Onion to Excess Boron
Authors: Francois L.E.
Published: February 2019

This study, conducted in large, outdoor sand cultures, was initiated to determine the effects of excess B on garlic (Allium sativum L.) and onion (Allium cepa L.) and to establish their B tolerances as measured by yield and quality of the marketable product. Boron treatments were imposed by irrigation with culture solutions that contained 0.5, 1.0, 5.0, 10.0, 15.0, or 20.0 mg B/liter. Relative yields of garlic and onion were reduced 2.7% and 1.9% with each unit (mg·liter-1) increase in soil solution B (BSW) above 4.3 and 8.9 mg B/liter, respectively. Increasing BSW reduced garlic bulb weight and diameter but did not significantly affect onion bulb weight or diameter. Boron concentration in leaves and bulbs was directly correlated to BSW.
Calcium Deficiency of Artichoke Buds in Relation to Salinity
Authors: Francois L.E. , Donovan T.J. , Maas E.V.
Published: February 2019

Globe artichokes (Cynara scolymus L.) were grown for 2 years in artificially salinized field plots in the irrigated desert area near Brawley, Calif. Saline treatments were imposed by irrigation with waters that contained equal weights of NaCl and CaCl,. Increased incidence and severity of Ca deficiency in the inner bracts of artichoke buds were directly related to increased levels of salinity. The Ca-deficient bracts were subject to infection by species of Botrytis and Erwinia. The number of marketable artichokes was reduced 20% or more when irrigation water salinity exceeded 2.0 dS·m–1, and up to 50% at 10 dS·m–1. Calcium deficiency in the artichoke bud is believed to be the result of disparate Ca distribution among the tissues, which is caused by high transpiration rates in the desert environment and the reduction in root pressure by soil salinity. Elemental analysis of leaf tissues can not be used to predict Ca deficiency within the artichoke buds.
Ethephon and 2,4-D Do Not Improve Periderm Color and May Decrease Yield in Red-skinned `Norland' Potato
Authors: Fritz Vincent A. , Hebel James B. , Borowski Alicia M. , Hung Patricia E.
Published: February 2019

Ethephon and 2,4-D were foliarly applied to red-skinned `Norland' potatoes (Solarium tuberosum L.) to determine if periderm color could be enhanced at harvest and throughout storage. Base rates of 250 and 185 ml·liter–1 for ethephon and 2,4-D, respectively, were applied at the onset of tuberization (tubers ≥ 2.5 cm in diameter). Base or double-rate foliar applications of either ethephon or 2,4-D resulted in significant U.S. No. 1 yield reductions and did not affect periderm color intensity at harvest or throughout storage sufficiently to warrant their use. Chemical names used: (2-chloroethyl)phosphonic acid (ethephon), (2,4 -dichlorophenoxy) acetic acid (2,4-D).
Quick Tree Decline: A New Problem of Macadamia in Hawaii
Authors: Oil David H. , Ueunten Gary , Yamaguchi Alan , Nagao Mike A. , Hara Arnold H. , Nishijima Wayne T.
Published: February 2019

A new problem of macadamia trees (Macadamia integrifolia Maiden and Betche) in Hawaii is characterized by slight leaf chlorosis, followed by rapid leaf browning, and tree death. Ambrosia beetle [Xyleborus affinis Eichhoff and X. perforans Wollastan (Coleoptera: Scolytidae)] infestations and fungal fruiting bodies were present on trees that subsequently exhibited the decline pattern. `Ikaika' was the most susceptible cultivar, and tree death occurred 8.3 ± 2.6Sd months after beetle infestations were detected.
Retention of Quality of `Golden Delicious' Apples by Controlledand Modified-atmosphere Storage
Authors: Lau O.L. , Yastremski R.
Published: February 2019

`Golden Delicious' apples (Malus domestics Borkh.) were subjected to either 0C controlled-atmosphere (CA) storage or to a postharvest coating of 1.0% to 2.5% Nutri-Save (NS; a polysaccharide derived from shellfish) plus air storage. NS-coated apples were greener and firmer and had higher titratable acidity (TA) and more shrivelled and injured fruit than the control after storage in air at 0C for 5 to 6 months and ripening in air at 20C for 7 days. Poststorage washing increased skin injury, and low relative humidity during ripening increased shriveling of NS fruit. NS applications led to an accumulation of CO2 and C2H4 and a small reduction of O2 in the fruit core cavities. The use of 1.5% O2 + 1.5% CO2 in the storage atmosphere was more effective than NS plus air storage in maintaining flesh firmness (FF) and TA without increasing fruit shrivel or skin injury. NS treatments maintained FF and a green skin in fruit ripened in air at 20C for 2 or 4 weeks following harvest, but some shrivel was evident by 4 weeks. Better retention of skin greenness was the only benefit derived from a poststorage NS treatment of CA-stored fruit during the shelf-life test.