bluuebunny/crossref_metadata_2025 huggingface dataset:
302 POLLINATION AND FRUITSET PATTERNS OF FIELD-GROWN PUMPKINS
Authors: Cady S. W. , Wien H. C
Published: February 2019

Investigations of varietal differences in pumpkin flowering and fruitset patterns were initiated in response to reports of poor fruitset by NYS growers. In addition, pollination requirements for marketable fruit were explored in one cultivar. Flowering date, fruitset, and fruit characteristics were recorded for 2 consecutive years in a RCBD of six popular Cucurbita pepo cultivars (Wizard, Happy Jack, Autumn Gold, Ghost Rider, Howden and Baby Bear). On average, female blossoms opened 38 days after 3-wk-old seedlings were transplanted into the field. Flowering period lasted for 3 to 4 weeks. No consistent pattern was found in female flower production nor fruitset until the last week when significant declines occurred. Each blossom only opens for one day and typically closes between 10 am and noon, limiting pollination opportunities. H and-pollination of Wizard' with various dilutions of pollen revealed that a minimum of approximately 2000 grains of pollen is necessary for fruitset. Removal of 66-75% of the stigmatic surfaces did not affect seed number or their location in the fruit, nor fruit shape or size. Fruit size was not correlated with seed number, although no fruit developed with less than 100 seed.
303 VARIATION IN SUMMER SQUASH FLOWERING IN RESPONSE TO ENVIRONMENT
Authors: NeSmith D. Scott
Published: February 2019

Research over a two year period assessed the influence of planting date and location on time to flowering and number of flowers produced for five summer squash (Cucurbita pepo L.) cultivars. Heat units (HU) were calculated using a single equation to determine if this approach could account for a significant portion of the variability in time to onset of flowering over the range of environments. Depending on cultivar and flower sex, the number of days to flowering varied as much as 20 days. There were significant cultivar differences in HU required for the onset of both staminate and pistillate flowers. The use of HU instead of days reduced the variability of time to flowering as indicated by regression analyses and mean absolute differences between predicted and observed days to flowering. The total number of staminate flowers produced was more variable than that of pistillate flowers. The ratio of pistillate-to-staminate flowers was stable for two of the five cultivars; however, pistillate flower production for those two cultivars was severely restricted during hot weather. Thus environment has a considerable influence on both the onset of flowering and the number of flowers produced for summer squash.
306 DECREASED ETHYLENE SYNTHESIS AND ALTERED FRUIT RIPENING IN TRANSGENIC TOMATOES EXPRESSING S-ADENOSYLMETHIONINE HYDROIASE
Authors: Bestwick Richard , Good X. , Kelloogg J. , Langhoff D. , Matsumura W. , Wagoner W. , Cloud G.
Published: February 2019

The gene encoding S-adenosylmethionine hydrolase (SAMase) was transferred to tomato (Lycopersicon esculentum, cv. large red cherry) as a means of reducing ethylene biosynthesis in the ripening fruit. S-adenosylmethionine (SAM), the penultimate precursor to ethylene in plants. is converted to methylthioadenosine and homoserine by SAMase thereby reducing the capacity of the transgenic plant to synthesize ethylene. We have used both constitutive and fruit-specific tomato promoters to regulate SAMase gene expression. Whereas the constitutive CaMV 35S:SAMase chimeric gene expressed active SAMase and conferred a 50-60% reduction in ethylene biosynthesis in a leaf disc assay, there was little effect on fruit ethylene synthesis or postharvest ripening physiology. The use of either the tomato E4 or E8 promoters restricted SAMase expression to ripening fruit which caused a substantial (80-90%) reduction in fruit ethylene synthesis and a profound effect on fruit ripening. SAMase expression levels reached 0.1% of total cellular protein as measured on western blots using anti-SAMase monoclonal antibodies. Field trial fruit picked al the mature green stage accumulated less lycopene and were twice as firm as controls over a six week period. Vine-ripened fruit had near-normal levels of lycopene, were firmer at harvest than controls, and did not lose firmness over a two week period. Taste, vitamin content and tomatine content were superior or equivalent to control tomatoes.
311 GENETIC AND MOLECULAR STUDIES OF DINITROANILINE HERBICIDE-RESISTANT GOOSEGRASS [Eleusine indica (L.) Gaertn.]
Authors: Zeng L. , Mysore K. S. , Baird Wm. Vance
Published: February 2019

Goosegrass (Poaceae) is a member of a small but economically important genus, containing approximately 10 species. Goosegrass is a noxious weed in cotton, soybean and turf production, but was effectively controlled by the application of dinitroaniline herbicides (DNH). However, in the early 1970's two DNH tolerant biotypes were discovered. The highly resistant (R-) biotype is now found in many areas in the southeastern US, while the intermediately resistant (I-) biotype is known only from SC. We have investigated the inheritance and expression of resistance, using radicle/root growth bioassays, in F2 progeny derived from F1 hybrids (created by outcrossing this autogamous weed). The hybrid nature of presumptive F1 seedlings was confirmed by isoenzyme analysis. The DNH's effect their herbicidal action by disrupting the assembly of tubulin dimers into microtubules (MTs). The R-biotype has been shown to possess MTs that are hyperstable in the presence of the herbicide. Mutation(s) in a tubulin protein would be manifested in the gene and might be detectable at the nucleic acid level. We found that the alpha-, beta- and gamma-tubulins are encoded by multigene families (∼ 5.7 and 8 members, respectively). DNA polymorphisms were detected, but were not strictly correlated with biotype. Therefore, the differences in herbicide response phenotype cannot be attributed to large deletions and/or insertions in a tubulin gene(s).
314 ROOTSTOCK EFFECTS ON SHOOT MORPHOLOGY OF `DELICIOUS' APPLE
Authors: Hirst Peter M. , Ferree David C.
Published: February 2019

One way in which rootstocks may influence production efficiency is by altering the number of spurs, and in particular reproductive spurs. However, rootstock influences on the morpholgy of shoots have not been quantified. Measurements were made on `Starkspur Supreme Delicious' trees growing on 17 rootstocks and planted in 1984 as part of the NC-140 regional rootstock trial. In each of the 6 years from 1988-1993, the length of the 2-year old section of wood of selected branches was measured and the number of spurs, flowers and shoots counted. For all rootstocks, trunk cross-sectional area was closely related to shoot length. Trees on P.22 (the most dwarfing rootstock in the planting) had shoot lengths 40-50% of those of trees on seedling rootstocks. For each rootstock, there was a strong negative relationship between shoot length and spur density, but there was not a common relationship among rootstocks. Similarly, flower number per shoot was also related to shoot length with different relationships for each rootstock. Flower density was not related to vigor for any of the rootstocks.
316 ROOTSTOCK AFFECTS RIPENING OF `MCINTOSH' APPLES
Authors: Autio Wesley R.
Published: February 2019

`Summerland Red McIntosh' apple trees propagated on M.9/A.2,O.3, M.7 EMLA, M.26 EMLA, M.7A. OAR1, or Mark rootstocks were planted in 1985 in a randomized complete block design with seven replications. Fruit ripening and quality were assessed in 1988-93. Internal ethylene concentrations were measured weekly throughout each harvest season. Once each season, fruit weight, starch-index value, soluble solids concentration, flesh firmness, and surface ted color were assessed on a sample of fruit from each tree. Size was smallest for fruit from trees on OAR1 or Mark, after accounting for the effects of crop load with analysis of covariance. Surface ted color was greatest for fruit from trees on Mark and least for fruit from trees on M.7 EMLA. Ripening was variable, but generally, fruit from trees on 0.3 ripened first, and fruit from trees on M.7 EMLA or M.7A ripened last. Crop load impacted ripening, but its effects were removed with analysis of covariance.
319 CONTROL OF FLORAL DEVELOPMENT IN APRICOT AND PEACH BY GIBBERELLIN
Authors: Weis Kitren G. , Southwick Stephen M. , Martin George C.
Published: February 2019

Gibberellic acid reduces return bloom in many fruit tree species. Reducing bloom may cut costs of hand thinning apricot, peach and plum fruit. Sprays of 250 ppm GA, during floral bud evocation (June 1993) resulted in bud death and abscission as determined by light microscopy sections in `Patterson' apricot (Prunus armeniaca L). GA treatment in May did not cause observable effects. August treatments, immediately prior to floral initiation, did not impede differentiation. Treatment of `Elegant Lady' peach (Prunus persica [L.] Batsch.) buds with 75-250 ppm GA, in late June, 1993 (evocation phase) did not have any discernable effects in that season with respect to abscission or differentiation. Treated peach buds differentiated simultaneously with untreated buds in early August. The patterns of response to GA treatment imply `windows of opportunity' with respect to effectiveness of GA treatments. The specific response suggests that apricot buds possess differing levels of sensitivity to GA treatment and probably reflect distinct phases in transition to flowering. In August buds were already `determined' and were in a potentially floral state that was irreversible.
320 REPRODUCTIVE DEVELOPMENT AND FRUIT QUALITY OF SWEET CHERRY
Authors: Andrews Preston K. , Collier Margaret L.
Published: February 2019

Variability in maturity and quality of sweet cherry (Prunus avium L. `Bing') fruit at harvest is a major limitation to the crop's storage and marketing potential. Later blooming flowers resulted in poorer fruit quality Differences in bloom date were related to differences in flower primordial development during winter. Vigorous shoots grown in the previous season produced fewer flower buds per length of shoot than did shorter, less vigorous shoots, resulting in larger flower primordia on vigorous shoots, The effects on primordial and fruit development of altered leaf areas per flower bud the previous summer were examined. A decrease in leaf area per bud during summer reduced primordium size in mid-winter. Dormant flower primordia of 6-yr-old `Bing' trees on precocious `Giessen' rootstock, Gil48/1, were larger than those with `Mazzard' as rootstock. Flower primordia on dwarfing Gil48/8 rootstock were intermediate in size. Differences in primordial development and bloom date, whether due to management practices or rootstock, may affect fruit development and contribute to variability in fruit maturity and quality.
324 SEED LENGTH AS A DEVELOPMENTAL MARKER FOR PREDICTING HARVEST DATE OF EARLY SEASON'MAYFIRE' NECTARINES
Authors: Day Kevin R. , DeJong Ted M. , Johnson R. Scott
Published: February 2019

Previous research with Mayfire nectarine demonstrated that seed length can be used as a developmental marker to predict the optimum date of girdling. Four years of study indicates that seed length also appears to be an effective physiologic marker for integrating early season heat accumulation. Seed length development was more highly correlated with heat accumulation (r=0.936) than with number of days after bloom (r=0.699). However, harvest date is more accurately predicted by number of days between 12mm seed length and harvest (30±1) than by degree-days between 12mm seed length and harvest (337±21).
329 DIFFERENTIAL THERMAL ANALYSIS OF RABBITEYE BLUEBERRIES
Authors: Hughes Gena R. , Matta Frank B.
Published: February 2019

Acclimation and cold hardiness of blueberry buds (Vaccinium ashei cv. Tifblue) were evaluated using differential thermal analysis (DTA) and tissue browning. Buds exhibited a single exotherm at -7C October through December and at -11C January through April. LOW temperature exotherms (LTE) were not detected. Tissue browning test ratings indicated that ovary death occurred at -21C.
334 RESTRICTION FRAGMENT LENGTH POLYMORPHISM IN CARROT
Authors: Sampath Vivek , Simon Philipp
Published: February 2019

Studies of genetic variation at the DNA level in the genus Daucus have been very limited. Molecular markers based on restriction fragment length polymorphism (RPLP) have been shown to be highly useful and efficient gene markers in other plant species.

We have used a total of 20 carrot types (inbreds, varieties, species) for this study. Genomic DNA probes cloned in pGEM (Promega) plasmid of Escherichia coli were hybridized to DNA of these types digested with EcoRI and HindIII restriction enzymes. Based on 50 probe-enzyme combinations we have found RFLP variation to be extensive in Daucus, even among related cultivated genetic stocks. The implications of these results in the germplasm diversity in Daucus will be discussed.

Also, a genetic linkage map of carrot will be constructed. The map will be used to determine the genomic regions conditioning traits like root and core diameter, root length, and nematode resistance.
335 ORGANIZATION OF ARTICHOKE, CYNARA SCOLYMUS L., BASED ON RAPD MOLECULAR MARKER BANDING PATTERNS
Authors: Tivang Jan G. , DeVos Neal , Nienhuis James , Skroch Paul
Published: February 2019

Individual heads (capitula) from five discrete artichoke, Cyara scolymus L., populations were evaluated using RAPD markers. One vegetatively-propagated cultivar; Green Globe; two seed-propagated cultivars, Imperial Star and Big Heart XR-1; and two breeding populations were examined. Twenty-seven RAPD primers were scored yielding 2 to 16 polymorphic bands resulting in a total of 178 bands. Our objective was to determine if RAPD markers could be used to distinguish between and within populations. The genetic relationships among populations as well as among individuals within each population were estimated using the ratio of discordant to total bands scored. Data reduction (MDS) provided a plot indicating five clusters corresponding to the five populations. Confirmation of the presence of five discrete clusters was obtained by analysis of variance of the marker frequencies. The genetic diversity index (GDI) was calculated for each populations as the pooled variance of band frequency for each population. The GDI values were highly correlated to the mean genetic distance within each population. The homogeneity of variance for the GDI values associated with each population were compared using the Siegel-Tukey test for homogeneity of spread.
337 WHAT DOES IT TAKE TO GET A CULTIVATED BEAN?
Authors: Koinange E.M.K. , Singh S.P. , Gepts P.
Published: February 2019

Cultivated plants and their wild progenitors show marked phenotypic differences regarding seed dormancy, the ability to disperse seeds, growth habit, phenology, photoperiod sensitivity, etc. We have used RFLP mapping to investigate the genetic control of these differences in a recombinant inbred population derived from across between a snap bean and a wild bean. Traits were scored either at Davis or in Colombia. Our results suggest that the genetic control is relatively simple. In particular, most of the phenotypic variation (>60%) in the population could be accounted for in genetic terms for all but two traits. The genetic control of many traits involved genes with major effect (>30%). Some regions of the genome had major effects on several traits. Our results suggest that evolution can proceed by macromutations, domestication could have taken place fairly rapidly and introgression of additional genetic diversity could be itrogressed relatively easily from wild beans into the cultivated bean gene pool.
348 SENESCENCE OF DAYLILY (HEMEROCALLIS) IS ASSOCIATED WITH EXPRESSION OF A MADS-BOX GENE
Authors: Lange Nathan E. , Reid Michael S. , Valpuesta Victoriano , Guerrero Consuelo , Botella Miguel A.
Published: February 2019

As in many commercially important flowers, especially the monocotyledonous geophytes, senescence of the ephemeral daylily flower (Hemerocallis) does not involve ethylene. By differentially screening a cDNA library constructed from mRNA extracted from daylily petals in the earliest stages of senescence, clones were isolated whose transcription is up-regulated coordinately with the onset of senescence. One of these clones, sen12, was found to be a transcription factor. The deduced amino acid sequence of sen12 contains a MADS-box and an associated K-box similar to transcription factors suggested to control floral morphogenesis in a variety of different species. Northern blot hybridization showed sen12 to be highly upregulated before and during visible flower senescence. The expression of homologous genes during senescence of other flowers will be reported.
363 INHERITANCE OF CITRUS NEMATODE RESISTANCE AND ITS LINKAGE WITH RAPD MARKERS IN CITRUS
Authors: Ling Peng , Gmitter Fred G. , Duncan Larry W. , Xiao S. Y.
Published: February 2019

A family of 63 citrus intergenemic backcross hybrids was used for this study. The parents and hybrids were multiplied by rooted cuttings, with 6 uniform replicates selected per hybrid, and each plant was inoculated with citrus nematodes (Tylenchulus semipenetrans) 5 times over 2 mo. The number of nematode female larvae per gram of fine fresh root was determind 2 mo after the last inoculation. The phenotypic variation of the hybrids was continuous and wide-ranged, from 8.0 females· g-1 of root tissue (resistant parent Swingle citrumelo=15.6) to 620.0 females· g-1 of root tissue (susceptible parent LB 6-2=540.5). Bulked segregant analysis (BSA), using RAPD fragments, was conducted with 2 DNA bulks of individuals from the extremes of the phenotypic distribution. Three hundred twenty primers were screened and 5 were found to generate repeatedly single RAPD fragments specific to the resistant bulk. The segregation of resistance-associated fragments among the individuals was examined, and the linkage between these markers and potential nematode resistance loci was estimated.
367 QUALITY OF `MANILA' MANGO AFTER HEAT TREATMENTS FOR FRUIT FLY DISINFESTATION
Authors: Shellie Krista C.
Published: February 2019

`Manila' mangoes (Mangifera indica) were immersed in 46C water for 65 or 75 minutes, or exposed to 45, 50 or 52C moist, forced-air (MFA) for 240, 100, and 98 minutes, respectively Mangoes exposed to 50 or 52C MFA had a significantly higher incidence of internal cavitation than mangoes exposed to 45C MFA; mangoes immersed in 46C water for 65 or 75 minutes, or control fruit. Shrink wrapped and nonshrink wrapped mangoes were exposed to 45C MFA for 240 minutes or 52C MFA for 98 minutes to evaluate whether the concentration of oxygen and carbon dioxide inside the fruit influenced cavitation development. Shrink wrapping per se had no significant effect on cavitation development Mangoes heated in 45C MFA for 240 minutes, 52C MFA for 98 minutes, or 46C water for 65 minutes were hydrocooled in 23C water or air cooled at 23C to evaluate whether heat dose influenced cavitation development. Hydrocooling had no significant effect per se on cavitation development though it significantly reduced the heat dose. The above results suggest that tolerance of 'Manila' mango to disinfestation heat treatments is more influenced by a maximum flesh temperature threshold than the heating method, heat dose, or fruit internal atmosphere.
380 CONSUMERS EVALUATE SERVICE QUALITY HIGHER FOR TEXAS FLORISTS THAN SUPERMARKET FLORAL DEPARTMENTS
Authors: Becker Wayne A. , Johnson James L. , Behe Bridget K. , Townsend Christine D. , Litzenberg Kerry K.
Published: February 2019

A survey instrument developed to assess service quality in non-horticultural industries (SERVQUAL) was modified and administered to customers of eight florists and 22 supermarket floral departments in Texas. Sixty-six percent of 722 florist and 409 supermarket floral department responding customers had made a floral purchase within 12 weeks of the survey. Their responses were used in the service quality evaluation. Florists met consumer expectations better than supermarket floral departments each of five issues: tangibles, reliability, responsiveness, assurance, and empathy (p=0.0001). Florist customers perceived their retailer gave higher quality service than supermarket floral customers.
391 THE INFLUENCE OF COLD DURING SEEDLING STAGE AND PHOTOPERIOD ON FORCING PERENNIALS FOR POT PLANTS
Authors: Armitage Allan M. , Thomas Paul
Published: February 2019

The influence of cooling, photoperiod and chemical branching on early spring flowering of perennial species was studied. Cooling was provided while plants were in plugs (128 plugs per tray) and dikegulac-sodium, a compound found to induce breaks in other species, was applied prior to, during and after cooling. Plants were cooled in insulated lighted coolers for 4, 8 or 12 weeks at 4C, and brought to a greenhouse with night temperatures between 8-12C. Long and short days were provided in the greenhouse after plants came out of the coolers. Little response to dikegulac occurred, however, Campanula, Sedum, Leontopodium, Catananche, Aubrietia, Arabis, Gypsophila, Anchusa and Aquilegia responded to cooling and photoperiodic treatment. Flowering and vegetative characteristics such as internode elongation and plant height responded to photoperiod and cooling but not all genera responded similarly. Anchusa, Campanula, Aquilegia and Gypsophila flowered significantly earlier under LD compared to SD. Twelve weeks of cooling resulted in flowering of all genera, however, some genera were equally responsive to shorter cooling times.
392 CHILLING TEMPERATURE AND DURATION AFFECT FLOWERING AND BUD ABORTION OF `PRIZE' AZALEAS
Authors: Womack William M. , Nell Terril A. , Barrett James E.
Published: February 2019

Dormant-budded `Prize' azaleas (Rhododendron sp.) were held at 2C, 7C, 13C, or 18C for 1, 2, 4, 6, 8, or 10 weeks then forced in walk-in growth chambers (29C day/24C night). Holding at 2C delayed flowering by 5-7 days over 7C and 13C. Plants held at 2C, 7C, or 13C for at least 4 weeks had approximately 50% buds showing color at marketability (8 open flowers). Plants held at 18C never exceeded 35% buds showing color at marketability. Increase in buds showing color was not apparent for plants were held at 7C, 13C, or 18C for more than 6 weeks; however, holding at 2C resulted in increasing percentages of buds showing color for holding periods longer than 6 weeks. Plants chilled at 13C and 18C showed significant increases in bud abortion after 8 or 10 weeks of cooling with most plants never reaching marketability (8 open flowers). These plants also had an increased proliferation of bypass shoots during cooling and forcing over other treatments.
414 PB 033 STAMP OUT HORTICULTURE!
Authors: Conley M. Elizabeth , Schwarze Debra J. , Lambe David P.
Published: February 2019

Rubber stamps have traditionally been used in business to deliver visual or concise verbal messages. That tradition has changed as rubber stamps have also become an art form. Stamps are now available in virtually any horticultural design, including flowers, vegetables, fruits, trees, cacti, turf and as landscape design forms.

Stamps can be purchased at specialty stores, craft stores, book stores, kiosks at shopping malls, and from catalogs or they can be easily crafted from gum or rubber erasers. Two periodicals are available that describe stamping techniques and provide catalog sources: Rubberstampmadness (Corvallis, Oregon) and Rubber Stampers World (Placerville, California).

Using rubber stamps is fun and promotes creativity! Stamps can be used in a wide range of colors and they allow versatility in positioning, whether on paper or fabric. They are cost effective because they can be reused. Some suggested uses include enhancement of visual displays, personalization of mailings, and application for 4-H projects.

A list of selected references will be available.
416 PB 089 GOPHER THROUGH INTERNET TO CONSUMER HORTICULTURE INFORMATION
Authors: Relf Paula Diane , McAnge Thomas , Dobbs Kathleen
Published: February 2019

The Internet is a system of nearly 10,000 computer networks linked together in cooperative, non-centralized collaboration. There are more than a million host computers in 36 countries from universities, research groups, companies and government installations. GOPHER is a tool that allows someone to look for information by moving through menus in the Internet system until specific documents are Identified that are of value to the researcher. A GOPHER Server has been established at VPI & SU for the Extension Service as follows:

Horticulture

Consumer Horticulture

(Includes the following topic areas: Environmental Issues; General Horticulture Information; Human Issues in Horticulture; Pest Management; Plant Fact Sheets; Virginia Gardener Extension Publications; Virginia Master Gardeners)

This information will be of value to educators, writers and private gardeners wanting current information on diverse consumer horticulture topics. The Human Issues in Horticulture information will be of particular value to researchers seeking information or collaborators in research related to the economic, environmental, psychological, physiological, social, cultural or aesthetic benefits of plants to people.
417 PB 092 BENNETT/JOHNSON PRAIRIE USER SURVEY
Authors: Hanchek Anne M.
Published: February 2019

Why do people visit the grounds of a botanical garden or arboretum? What draws them to that “experience of nature”? What can we do as horticulturists, landscape architects, and educators to make garden areas more appealing and fulfilling to visitors? The Prairie Interpretive Committee of the Minnesota Landscape Arboretum asked these questions in 1991 as it convened to analyze the current and future status of the Arboretum's Bennett/Johnson Prairie. To understand visitor usage and needs, Arboretum members were surveyed about frequency of visits, reasons for visiting, specific visitor services, and suggestions for improvements. Among the 151 responses, the major reasons for visiting were the pleasures of walking, observing, and being at peace. “Open”, “wild,” and “natural” were common key words. There was keen interest in native plants and their historical role as well. Sitting areas, maps, path markers, plant labels, and self-guided tours were the primary requests for improvement. A high percentage found the demonstration area interesting and useful. The Interpretive Committee used this research to guide the landscape architect, create a brochure, and develop an integrative master plan for the prairie area.
419 PB 098 MINNESOTA INSTITUTE FOR SUSTAINABLE AGRICULTURE: A PARTNERSHIP OF THE UNIVERSITY AND COMMUNITY GROUPS
Authors: Murray Helene , Wyse Donald L. , Hoover Emily E.
Published: February 2019

Minnesota has a long history of strong citizen involvement in environmental, community development, economic development, and human rights issues. Therefore, it is not surprising there are many individuals, organizations, communities, and educational institutions in Minnesota actively involved in the sustainable agriculture debate. The challenge we face is how to help these strong forces work in collaboration to solve rural problem s.

In 1990 representatives of five community-based organizations and the U of M agreed to form the Minnesota Institute for Sustainable Agriculture (MISA) to be housed at the University and governed by a board of community and University representatives. The purpose of MISA is to bring farmers and other sustainable agriculture community interests together with University administrators, educators, researchers, and students in a cooperative effort to undertake innovative, agenda-setting programs that might not otherwise be pursued in the state.
420 PB 121 Farmer/Scientist Research In Participatory On-farm Trials
Authors: Seiter Stefan , William Ray , Luna John , McGrath Dan , Tenpas Tom
Published: February 2019

A project was initiated in which a collaborative and mutual learning process was emphasized to (1) improve farmer designed research and to facilitate learning among farmers, research and extension, agribusiness and government agencies; (2) to enhance vegetable production systems by improving farm profitability, protecting water quality, and enhancing long-term soil productivity. The poster displays mutual learning that occurred during each step of the following process:
428 PB 165 SPATIAL AND TEMPORAL VARIATION IN ORCHARD SOIL NITROGEN EXTRACTABILITY
Authors: Sampson Hilary J. , Weinbaum S. A.
Published: February 2019

Extractable soil N may be leached below the plant rooting zone. and into the ground water. Orchards devoid of actively growing winter cover crops are subject to the greatest risk of NO3- leaching during tree dormancy in California. We examined the patterns of KCl extractable NH4+ and NO3-. and potentially mineralizable N (PMN) in the top 10 cm of soil across transects (60 samples, 150 m) in 3 almond orchard systems at 5 phenological stages in 1993. Extractable N was affected both spatially and temporally by management practices (e.g. herbicide or fertilizer application) and soil temperature. PMN did not exhibit local spatial patterns; geostatistical analysis revealed a trend across the transects indicating a larger scale of soil variation. possibly resulting from land leveling. The conventionally-managed orchard without a cover crop demonstrated higher levels of extractable NH4+ and NO3- in the top 10 cm in Feb. and Nov. 1993, compared with orchards managed with organic fertilizers and winter cover crops.
435 PB 206 EFFECT OF MYCORRHIZAL FUNGI AND PHOSPHORUS ON GROWTH AND NUTRIENT UPTAKE OF NEEM TREE SEEDLINGS (AZADIRACHTA INDICA A. JUSS)
Authors: Phavaphutanon Lop , Davies Fred T.
Published: February 2019

Growth and nutrient content of neem tree seedlings (Azadirachta indica A. Juss) were studied in response to the mycorrhial fungi Glomus intraradices Schenck & Smith and Long Ashton Nutrient Solution (LANS) modified to supply phosphorus (P) at 0.65 and 1.30 mM P. Three months after inoculation, an extensive mycorrhizal colonization was observed in mycorrhizal plants at both P levels. Shoot growth of mycorrhizal plants was similar at both P levels while the growth of nonmycorrhizal plants increased with increasing P supply. Mycorrhizal plants had greater leaf area, shoot dry weight and root to shoot ratio than nonmycorrhizal plants at the same P level. The length of nonsuberized roots increased with increasing P supply regardless of mycorrhizal colonization while the length of suberized roots was significantly increased by mycorrhiza. Mycorrhiza altered dry mass partitioning to root systems resulting in greater length and dry weight of suberized roots in mycorrhizal plants. Mycorrhiza also improved nitrogen, phosphorus, calcium and sulfur uptake but did not affect micronutrient uptake, except for enhancing boron.
445 PB 256 QUERCETIN AND QUERCETIN GLYCOSIDE CONTENT VARIATION IN DIFFERENT ONION (Allium cepa L.) VARIETIES AND GENOTYPES
Authors: Patil Bhimanagouda S. , Pike Leonard M.
Published: February 2019

The anti carcinogenic flavonol, aglycone, or free quercetin and quercetin glycoside content of seventeen onion varieties and 22 genotypes (Asgrow seed co.) and also 37 breeding lines (Texas A&M University) were analyzed by high performance liquid chromatography (HPLC). Quercetin glycosides were hydrolyzed into aglycones.

Total quercetin content in yellow and red onions varied from 80.34 to 286.4 mg/kg fresh weight in different varieties. Marked variation in total quercetin content between Texas A&M breeding lines (56-202 mg/kg fresh weight) and Asgrow breeding lines (54-287 mg/kg fresh weight) was observed. White onions contain trace amount of total quercetin. Free quercetin in Texas A&M breeding line 20272-G was 12.4 mg/kg fresh weight; however, other varieties and breeding lines contain negligible amount of free quercetin. It was concluded that the `designer' onion varieties with high quercetin content for health consciousness can be produced.
448 PB 285 NEW EGGPLANT AND PEPPER CULTIVARS FOR HAWAII AND THE PACIFIC BASIN
Authors: Takeda K.Y.
Published: February 2019

Two long eggplant (Solanummelongena L.) hybrids, Nitta/Molokai F1 and Nitta/Waimanalo F1, were released to growers. The hybrids represent an improvement over presently grown cultivars by producing higher yields of quality fruit. Quality factors such as dark maroon color, uniformity of fruit shape and long shelf life are important considerations for growers and consumers.

Two pepper varieties (Capsicumannuum L.), `Kaala' and `Waialua' were developed for those areas in Hawaii and the subtropics which have limited pepper production because of bacterial wilt (Pseudomonus solanacearum). The varieties were the result of a cross between `Chabai Merah' and keystone Resistant Giant. `Chabai Merah', a Malaysian pepper variety is highly resistant to bacterial welt and rootknot nematode. `Kaala' is a sweet pepper and is highly tolerant to bacterial wilt if grown at temperature below 27%. Waialua is a pungent type pepper and is highly resistant to bacterial wilt.
451 PB 294 BREEDING SAVORY PEPPER” FOR ADAPTATION IN NORTHEAST U.S
Authors: Grun Paul , Orzolek M.D.
Published: February 2019

Savory Peppers™ (Sp™) is the low heat form of Capsicum chinense from northern South America where it is widely used as a condiment. We are adapting it to northeastern conditions through introgression of genes from adapted C. annum, selection within SP™, and use of improved culture methods. Introgression is progressing in spite of species isolation barriers expressed as failure of F1 seeds to germinate, and F1 and later generation male sterilities. Selection has been carried out on plants of two landraces, producing ten improved strains which were tested at three stations last summer: 1) west PA on sandy soil with long growing season: 2) central PA on clay loam with short growing season, and 3) eastern PA on clay loam with long growing season. Strains of both landraces yielded well in region 1), and poorly in region 2), and one landrace yielded well in region 3), while those of the other yielded poorly as a result of early wilt. Roles of soil and temperatures in producing these results will be discussed.
455 PB 326 PISTIL INFLUENCE ON GROWTH OF POLLEN TUBES OF P. X DOMESTICUM
Authors: Stuart Mary , Jourdan Pablo
Published: February 2019

The regal pelargonium (P. x domesticum) is generally characterized by low fertility and poor seed set. In studys designed to assess factors that contribute to low fecundity in this crop we have examined genotype interactions among various cultivars and have identified lines that differ in degree of male and female fertility.

The objective of this study was to examine genotypic variation, other than self-incompatibility, of P. x domesticum pistils in supporting the development of the male gametophyte. Variation in pollen germination and growth was assessed after crossing either a male of high fertility or a mate of poor fertility to nine different selections of varying female fertility. Styles were harvested 2 hours after pollination and examined using fluorescence microscopy to determine the number of germinated pollen grains on the stigma and the number of pollen tubes growing down the style.

Female selections displayed large differences in their ability to support pollen tubes. Styles from different females pollinated with the same male varied in average number of pollen tubes from 30 to 2.
464 PB 321 IDENTIFICATION OF RAPD MARKERS ASSOCIATED WITH QTLs CONTROLLING DROUGHT TOLERANCE IN PINTO BEANS
Authors: Schneider Kristin , Kelly James D.
Published: February 2019

Common beans, considered sensitive to moisture stress, are an important commodity in developing countries such as the Mexican Highlands where intermittent drought conditions are prevalent during the growing season. The selection and development of high performing cultivars under drought stress is confounded by the quantitative nature of drought tolerance. To employ indirect selection in earlier generations, RAPD markers were identified that associated with QTLs controlling performance under drought stress. RAPD markers are preferred for use in Phaseolus vulgaris, over RFLPs, because they generate polymorphisms between genetically related germplasm. 48% of 620 arbitrary primers screened against three parents of two F6 derived recombinant inbred pinto populations were polymorphic for one or more bands. These polymorphisms were screened against RILs in each population and associations were determined using one-way ANOVAs and Mapmaker. Yield data used for determination of associations was collected over five years in MI and Mexico where both stress and non stress treatments were applied.
472 PB 364 GENETIC TRANSFORMATION AND REGENERATION OF MUNG BEAN USING AGROBACTERIUM RHIZOGENES
Authors: Zhan Shuhua , Lu Zhongfang , Huang Y.
Published: February 2019

Mung bean (Vigna radiata L.) is one of the economically important crops in Southeastern Asia and also grows in USA. Genetic transformation of mung bean has been achieved using an Agrobacterium -mediated transformation system. Two transformation methods were used in this study. With the leaf-disk transformation method, freshly cut leaf strips from young seedlings of mungbean were co-cultivated for 72 hours with either a wild-type A. rhizogenes strain 11325 or the strain containing an additional binary vector carrying the npt gene. In another method, agrobacteria were applied to wounded hypocotyls of aseptically germinated seedlings. After infection, the explants were placed on shoot induction medium. Within 3-4 weeks, shoots developed from the edges of leaf disks as well as from the inoculated sites on hypocotyls. Putatively transformed shoots were selected in vitro based on their ability to root in the kanamycin-containing medium. The npt gene fragment and a-few of T-DNA fragments from the wild-type Ri plasmid were detected in regenerated mungbean plants by Southern blot analysis. These results suggested that foreign DNAs from both the Ri plasmid and the binary vector had integrated into the genome of mung bean. These transformation systems for mung bean can now be used to introduce agronomically desirable traits into this crop for its genetic improvement.
478 PB 402 CORE COLLECTION OF CAPSICUM GERMPLASM
Authors: Rodgers Pamela Cole , Bosland Paul W.
Published: February 2019

Preservation of genetic diversity is of paramount importance in germplasm. A method of collecting, storing, and organizing genetic material to include maximum variability and to minimize repetition within the collection is a “core collection.” To assist the National Plant Germplasm System in developing a core collection, or core subset of Capsicum germplasm, field evaluations were conducted from 1989 to 1993 at New Mexico State University. In determining how best to organize the core subsets, we believe the objectives of a Capsicum core subset should be to increase the efficiency of evaluation and thus the utilization of existing collections and to provide for a manageable and representative selection of available Capsicum germplasm for use in research and plant breeding. We are using a modified IBPGR Capsicum descriptor list to evaluate the collection, With these objectives in mind, we are suggesting the following approach to Capsicum core subsets. At least one accession of each Capsicum species is contained in the core. The most economically important species, C. annuum, represents the majority of accessions. Within C. annuum the core subsets are grouped by pod-type (ancho, bell, jalapeno, etc.). The pod-type is analogous to races in maize (Zea mays).
486 PB 128 GROWTH OF ANNUAL SPECIES IN COCONUT COIR SUBSTRATES
Authors: Evans Michael R. , Stamps Robert
Published: February 2019

Helianthus annuus `Big Smile', Tagetes patula 'Bonanza Deep Orange' and Pelargonium × hortorum 'Pinto Rose' seedlings were transplanted into 12 cm (470 ml) pots containing substrates composed of 3 parts (v/v) vermiculite, 3 parts sand and 2 parts perlite. In addition, the substrates contained either 3 parts Florida peat, 3 parts coconut coir (coir), 6 parts coir or 12 parts coir, thus, resulting in 4 substrates. Dolomitic limestone, hydrated limestone, superphosphate, a microelement package and a 14-6.2-11.6 slow release fertilizer were added to the Florida peat-containing substrate. The same materials were added to the coir-containing substrates except that calcium sulfate (gypsum) was used in place of dolomitic and hydrated limestone. All materials were incorporated at rates required to obtain an initial pH of 5.5 to 5.8 and provide equal amounts of calcium, phosphorus and microelements. Data were taken 5 weeks after transplanting. Neither height, shoot fresh weights nor root fresh weights were significantly different between the substrates. Tagetes average heights were between 11.5 and 12.9 cm, while average shoot fresh weights were between 12.6 and 14.7 g and average root fresh weights were between 8.8 and 9.4 g. Helianthus average heights were between 18.4 and 19.9 cm, while average shoot fresh weights were between 29.7 and 31.9 g and average root fresh weights were between 19.6 and 22.3 g. Pelargonium average heights were between 11.9 and 13.4 cm, while average shoot fresh weights were between 13.8 and 15.3 g and average root fresh weights were between 3.4 and 3.7 g.
483 PB 134 PHYSICAL ANALYSIS OF FRESH AND AGED RICE HULLS USED AS A PEAT MOSS SUBSTITUTE IN GREENHOUSE MEDIA
Authors: Dueitt Shelly D. , Newman Steven E.
Published: February 2019

Rice hulls, a by-product of the rice milling process, were used at various rates to substitute sphagnum peat moss in greenhouse media. Previous studies demonstrated that media containing rice hulls replacing the vermiculite fraction grew plants equal to or better than traditional peat vermiculite blends. The objective of this study was to determine if rice hulls can replace sphagnum peat moss in a greenhouse medium. Physical properties, including bulk density, total pore space, and water retention were determined in media blended with fresh or aged rice hulls, sphagnum peat moss, and vermiculite. The bulk density of the media increased with increasing levels of fresh rice hulls. The pore space in media containing both fresh and aged rice hulls decreased over time during the crop production cycle and the pH increased.
495 PB 175 PHOSPHORUS SUPPLY CONTROL OF BEDDING PLANT SEEDLING ROOT/SHOOT RATIO
Authors: Huang JinSheng , Nelson Paul V.
Published: February 2019

It is desirable to have a large root mass and compact shoot in the final stage of plug seedling production. Marigold `Discovery Orange' was grown for six weeks from sowing in a hydroponic system. Hoagland's all nitrate solution was used at 0.25X for the first three weeks and 0.5X for the final three weeks. P was applied continuously in the control and was eliminated for the first one or three weeks in the two stress treatments. Weekly mot and shoot dry weights indicated: a.) P stress caused an increase in root/shoot ratio with roots larger than in the control plants and b.) restoration of P after a P stress resulted in a rapid shift of root/shoot ratio back to the control level with final root and shoot weights less than in the control plants. A continuous marginal P stress or a stress near the end of seedling production is suggested. Tomato `Marglobe' was grown for five weeks and impatiens `Super Elfin White' for six weeks in a 3 sphagnum peat moss: 1 perlite substrate in 288 cell plug trays. Fertilizer was applied at every third watering at a zero leaching percentage. The control nutrient ratio (mM) was 5.4 NH4+ NO3: 0.5 PO4: 1.6 K while the low P treatments contained 0.15, 0.1, and 0.05 mM PO4 throughout the experiment. The root/shoot dry weight ratios increased in the low P treatments. Tomato plants at 0.15 and 0.1 mM P and impatiens plants at 0.15 mM P had larger roots than the control plants. A continuous stress at 0.15 mM PO4 appears promising.
496 PB 178 AMMONIUM TOXICITY DURING PLUG SEEDLING GERMINATION AND PRODUCTION
Authors: Lee JiWeon , Nelson Paul V.
Published: February 2019

Tomato `Marglobe' seed were sown on germination paper in enclosed plastic dishes in a growth room Ammonium was more toxic when applied as the single salt, ammonium sulfate, than when applied as part of a complete Hoagland solution. The lowest toxic ammonium levels were for the single salt 1.5 mM and for the complete solution 4.5 mM. Symptoms included reduced length of primary and particularly lateral roots, reduced numbers of root hairs, and chlorosis, distortion, and slower development of cotyledons. Tomato `Marglobe' seedlings were also grown in 288 cell plug trays in a substrate of 3 sphagnum peat moss and 1 perlite containing no N, P, or K but amended with dolomitic limestone to pH 6.0 They were fertilized every third watering with 4 mM NH4 + NO3, 0.4 mM PO4, and 1.2 mM K from 15 to 28 days after sowing and at double this concentration from 29 to 42 days. A zero leaching percentage was practiced. Ammoniacal-N comprised 25, 50, or 75% of total N. There were no effects of ammonium on root or shoot weights, height or appearance of plants through this period. Plant growth was limited throughout this period by N stress in accordance. with commercial practice. After 42 days N stress was alleviated by again doubling the nutrient solution concentration and applying it with every watering. Ammonium toxicity developed with symptoms of shorter plant height, general chlorosis of lower leaves, and necrosis of the base of lower leaves.
508 PB 254 EFFECT OF CARBON DIOXIDE ENRICHMENT ON PRODUCTION AND QUALITY OF GREENHOUSE `ROYALTY ROSES PRODUCED IN COASTAL CENTRAL CALIFORNIA
Authors: Tjosvold Steven A.
Published: February 2019

The atmosphere of commercial greenhouses were enriched to 1200 μl·1-1 carbon dioxide 1 hour before sunrise and maintained until ventilation was necessary to cool the greenhouse and again anytime the greenhouse vents were closed in the daytime. Enrichment was only possible, on average, for 5 daylight hours in the winter and less in the warmer months. In the first 10 month experiment, total production was not different in carbon dioxide enriched greenhouses. Stem lengths of harvested flowers were generally longer in the enriched greenhouses, particularly in the winter months. In the second 10 month experiment, total production was again not different in carbon dioxide enriched greenhouses, however, stem length was only slightly longer in the winter months. Dry weights of flower buds, stems and leaves increased slightly but only in winter months.
514 PB 444 VIRULENCE OF ERWINIA AMYLOVORA STRAINS ON PEAR
Authors: Hunter David M. , Bonn W. Gordon
Published: February 2019

The virulence of six strains of Erwinia amylovora used in combination for screening fire blight resistance of pear seedlings and advanced selections from the Harrow pear breeding program was evaluated by inoculating a standardized suspension (108 cfu/ml) of the six strains individually and in combination into actively growing shoot tips and measuring the lengths of the diseased shoots six weeks later. Three cultivars provided a range of resistance to fire blight: `Bartlett' was susceptible, HW-605 (`Seckel' × NJ-6) was moderately resistant, while `Kieffer' was resistant. On `Bartlett', one strain was consistently more virulent than the combination, while on HW-605, two strains were consistently more virulent than the combination. One strain was consistently less virulent than the combination on both `Bartlett' and HW-605. No strain was consistently more or less virulent than the combination when inoculated into `Kieffer'. Lesion lengths were greater in the susceptible cultivar `Bartlett' than in either HW-605 or `Kieffer'. These results suggest that a combination of strains of E. amylovora is appropriate for screening for fire blight resistance in pear genotypes.