bluuebunny/crossref_metadata_2025 huggingface dataset:
JAPANESE BEETLE (Popilla japonica NEWMAN) FEEDING PREFERENCE ON BIRCH TAXA (BETULA)
Authors: Gu Mengmeng , Robbins James A. , Rom Curt R. , McAfee Jason
Published: June 2019

Japanese beetle (Popilla japonica Newman) has caused severe damage on a wide range of horticultural crops since its first introduction to the Eastern United States from Japan in 1916. Leaves are skeletonized by adult beetles feeding in masses, which makes this insect damage easy to identify. In Arkansas, Japanese beetle was first trapped in Washington County in 1997 and has reached epidemic proportions in the most recent three years. Leaf skelotonization and feeding preference on eighteen birch accessions by Japanese beetle were recorded in 2003 and 2004. There was a wide range from no feeding (0% leaf skelotonization) to high feeding preference (89% leaf skelotonization). Betula utilis var. jacquemontii and B. papyrifera `Renaissance Upright' had highest preference. Betula pendula `Laciniata' had no feeding damage from Japanese beetle.
INHERITANCE OF VARIEGATED AND PURPLE FOLIAGE PHENOTYPES IN Hypericum androsaemum L.
Authors: Olsen Richard T. , Ranney Thomas G.
Published: June 2019

Inheritance of two mutant foliage types (purple and mottled variegated) was investigated for diploid, triploid, and tetraploid tutsan (Hypericum androsaemum). Segregation ratios were determined for diploid crosses in reciprocal dihybrid F1 and F2, BC1P1, and BC1P2 families. F2 tetraploids were derived from autotetraploid F1s. Triploid segregation ratios were determined from crosses between autotetraploid F1s and diploid F1s. Diploid di-hybrid crosses fit the expected 9:3:3:1 ratio for a single, simple recessive gene for both traits, with no evidence of linkage between each trait. Data from backcross and triploid crosses generally supported this model. In tetraploid crosses we observed twice as many variegated phenotypes as predicted which was not explained by random chromosome or chromatid assortment. Inheritance of purple foliage did not deviate from random chromosome assortment at the tetraploid level.
MOLECULAR MARKER-DERIVED GENETIC SIMILARITY ANALYSIS OF A SEGREGATING BLACKBERRY POPULATION
Authors: Stafne Eric T. , Clark John R. , Lewers Kim S.
Published: June 2019

A tetraploid blackberry population that segregates for two important morphological traits, thornlessness and primocane fruiting, was tested with molecular marker analysis. Both randomly amplified polymorphic DNA (RAPD) and simple sequence repeat (SSR) markers were used to screen a population of 98 genotypes within the population plus the two parents, `Arapaho' and `Prime-Jim' (APF-12). RAPD analysis averaged 3.4 markers per primer, whereas SSR analysis yielded 3.0 markers per primer pair. Similarity coefficient derived from the Dice index averaged over all individuals was 63% for RAPD markers, 73% for SSR markers, and 66% for RAPD and SSR markers together. The average similarity coefficients ranged from a high of 72% to a low of 38% for RAPD markers, 80% to 57% for SSR markers, and 73% to 55% for both. Comparison of the parents indicated a similarity of 67% for RAPD markers, 62% for SSR markers, and 67% for both. This is similar to a previous study that reported the similarity coefficient at 66%. Although inbreeding exists within the population, the level of heterozygosity is high. Also, evidence of tetrasomic inheritance was uncovered within the molecular marker analysis. This population will be used to identify potential markers linked to both morphological traits of interest. Further genetic linkage analysis and mapping is needed to identify any putative markers.
ANTHRACNOSE SEVERITY ON Euonymus fortunei GROWN ON PLASTIC OR GRAVEL WITH OR WITHOUT PERIODIC BLEACH APPLICATIONS
Authors: Boyer Cheryl R. , Cole Janet C.
Published: June 2019

Euonymus fortunei (Turcz.) Hand.-Mazz. is susceptible to anthracnose caused by Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. Fungicides have provided little control of anthracnose on E. fortunei in past studies. Identification of cultural practices that reduce disease incidence would be beneficial to the nursery industry. Containerized E. fortunei `Emerald'N Gold' plants were placed either on gravel beds or black plastic-covered gravel beds. Half of the beds in each bed treatment were sprayed with a 10% bleach solution monthly to attempt to reduce the presence of C. gloeosporioides inoculum. Plants were rated monthly from May (initial rating) through October for disease severity. A covariate analysis was performed using initial ratings as the covariate for ratings from all other months. Bleach did not affect disease ratings at any time. Disease ratings of plants on plastic-covered beds were lower than those of plants on gravel beds. Disease ratings decreased linearly as the growing season progressed.
EFFECT OF SUBSTRATES ON ROOTING OF STEM CUTTINGS OF THE ENDANGERED SPECIES Clematis socialis
Authors: Johnson C. N. , Eakes D. J. , Bruner L. L. , Wright A. N. , Sibley J. L
Published: June 2019

Clematis socialis Kral, also known as the Alabama Leatherflower, is an endangered species with only six known populations in northeast Alabama and northwest Georgia. Cutting propagation of the species would be beneficial for establishing additional self-sustaining populations and providing genetic material for future hybridization. A study conducted in 2000 and 2004 determined the effects of four nonamended substrates on root initiation and growth, as well as survival of C. socialis stem cuttings. Of the four substrates tested, including sand, perlite, vermiculite, and 1:1:1 (by volume) peat (P): pine bark (PB): sand (S), cutting survival was highest in sand in both 2000 and 2004. In 2000, sand also produced the longest roots and highest root quality. Vermiculite produced the longest and most roots and highest root quality in the 2004 study. In 2004, cuttings rooted in fine-particled substrates, such as sand and vermiculite, had higher cutting survival, root growth, root number, and root quality than those rooted in perlite and 1:1:1 (by volume) P:PB:S. The 1:1:1 P:PB:S substrate produced the lowest averages for all data collected in both the 2000 and 2004 studies. Sand was among the two highest performing media in both years, regardless of differences in IBA concentration, misting times, and environmental conditions, making it the overall best substrate for rooting C. socialis stem cuttings. Increasing the concentration of IBA in the rooting solution, providing a cooler environment, and decreasing the number and duration of misting cycles the cuttings received increased cutting survival, root length, root number, and root quality for all four substrates from 2000 to 2004.
PHENOLIC CONTENT AND ANTIOXIDANT CAPACITY IN DIFFERENT PECAN CULTIVARS.
Authors: Villarreal J. Emilio , Lombardini L. , Cisneros-Zevallos L.
Published: June 2019

The objective of this study was to evaluate kernels of different pecan (Carya illinoinensis) cultivars for their antioxidant capacity and characterize the nature of the antioxidant compounds. Nuts collected from four pecan cultivars `Cheyenne', `Cape Fear', `Desirable', and `Pawnee' were shelled, chopped and analyzed for their antioxidant capacity (AC), and for their phenolic, tannin, and vitamin C content. AC was measured using one spectrophotometrical [DPPH (2,2-diphenyl-1-picrylhydrazyl)] and one fluorescence method [ORAC (Oxygen Radical Absorbance Capacity)]. Total phenolic and tannin content were determined using spectrophotometrical assays. Finally, ascorbic and dehydroascorbic acid were determined using a high performance liquid chromatograph. Both AC methodologies, DPPH and ORAC, gave similar results with marked differences between cultivars. `Desirable' had the highest antioxidant capacity (47,747 μg TEq/g DW with DPPH method) followed closely by `Cheyenne' (36,192 μg TEq/g DW) and, with smaller amounts, by `Cape Fear' and `Pawnee' (16,540 and 13,705 μg TEq/g DW, respectively). Total phenolic content showed a similar trend but `Pawnee' showed a higher phenolic content than `Cape Fear'. `Cheyenne' had the highest amount of tannins, 9,114 μg/g DW, followed by `Cape Fear', `Pawnee' and `Desirable' with 7,764, 6,043 and 5,508 μg/g DW respectively),. `Cheyenne' had also the highest vitamin C content, up to ≈10-fold greater than `Cape Fear' and `Pawnee', the highest difference within the antioxidants analyzed. There is the need to determine the phenolic profile and degree of polymerization of tannins, their contribution to the AC and how they are affected by horticultural practices in order to better understand the nutraceutical potential of each cultivar.
THE EFFECTS OF STORAGE AND IONIZING IRRADIATION ON ANTIOXIDANT ACTIVITY, PHENOLICS, AND CAROTENOIDS IN POTATO (Solanum tuberosum L.)
Authors: Blessington Tyann , Scheuring Douglas C. , Miller J. Creighton
Published: June 2019

Potatoes are stored to ensure a continuous supply; however, losses due to shrinkage and sprouting can be large. It is believed that ionizing irradiation will become more prominent for sprout inhibition due to the increasingly higher operating costs of low-temperature storage and possible phase-out of chemical sprout inhibitors. The effects of storage and ionizing irradiation (gamma and electron beam) on antioxidant activity (AOA), phenolic content, and carotenoid content were analyzed using the potato cultivar Atlantic. Tubers were subjected to 0, 75, and 200 Gy γ-irradiation doses, stored at 20 °C, and analyzed after 0, 10, 20, 75, and 110 days. Tubers from another harvest were subjected to a surface dose of 0 or 200 Gy e-beam irradiation, stored at 20 °C, and analyzed after 0, 10, 20, 75, and 110 days. AOA was measured via the DPPH method; phenolic content via the Folin-Ciocalteau method and individual phenolics via HPLC; and carotenoid content via absorbance at 445 nm and individual carotenoids via HPLC. During early storage, higher doses resulted in higher AOA, while, during longer storage, lower doses produced greater AOA. Phenolic content increased in storage during the γ-irradiation study, but decreased in the e-beam study, partly due to increases in chlorogenic acid in the former and decreases in caffeic acid in the latter. The e-beam dose of 200 Gy resulted in significantly greater total phenolics than 0 Gy. Total carotenoids and lutein decreased with storage, but were not affected by irradiation. Storage exerted a much greater influence on AOA, phenolic content, and carotenoid content than either irradiation treatment.
RESPONSE OF COWPEA CULTIVARS TO RHIZOCTONIA SOLANI IN FIELD TESTS.
Authors: Thies J. A. , Berland P. A. , Fery R. L.
Published: June 2019

Rhizoctonia solani is an important pathogen of cowpea (Vigna unguiculata) in the southern U.S. and worldwide. Cowpeas are especially susceptible to seedling diseases caused by R. solani when planted in cold, moist, spring soils. Nine cowpea cultivars were evaluated in inoculated field tests at six planting dates in Charleston, S.C., during 2004. The cowpea cultivars evaluated were Bettergro Blackeye, Knuckle Purple Hull, Mississippi Silver, Colossus-80, Charleston Nemagreen, Texas Cream-40, White Acre, Coronet, and Charleston Greenpack. The tests were planted on 20 Apr., 29 Apr., 11 May, 19 May, 27 May, and 8 June. The experimental design for each test was a split-plot with six replicates. Whole plots were cultivars, and sub-plots were inoculation with R. solani and an uninoculated control. Rhizoctonia solani caused significant seedling losses in all cultivars evaluated during mid-April to early June and seed yields were reduced in the 11 May planting. In general, standard cowpea cultivars (Mississippi Silver, Colossus-80, and Coronet) had higher stand counts and produced heavier seed yields than other cowpea cultivars, although these standard cultivars were not resistant to R. solani. Resistant cowpea cultivars are needed to allow earlier planting of the crop in cold soils, which would extend the growing season and allow more efficient use of harvesting equipment and processing facilities.
FIVE-YEAR ASSESSMENT OF A MANDATORY INTERNSHIP PROGRAM
Authors: Kahn B.A.
Published: June 2019

An assessment was conducted for our departmental internship class (HORT 2010) for 1999–2003. With rare exceptions, all students majoring in Horticulture must complete 3 credits of HORT 2010, based on 480 hours of approved work, reports, a seminar, and evaluations. The course is graded pass/fail. An internship requirement was added to the Landscape Contracting major in 2000–01. Enrollment in HORT 2010 was greatest among students in the Turf Management option (TURF) in 3 of 5 years. Over the 5-year period, females averaged 27% of the enrollment in HORT 2010, in part because there was only one female TURF student. The mode for earned hours completed just before the semester of enrollment in HORT 2010 was 97, thus classing the typical intern as a rising Senior. Only 8% of the interns failed to graduate. A total of 126 students interned at 109 different sites, with 70% interning within Oklahoma. Four Oklahoma employers accounted for 23% of all internship employment. Feedback has led to documented program improvements, e.g., `Bilingual Horticultural Communications' was made available on campus via distance education in Spring, 2001; `Turfgrass Integrated Pest Management' was created and added to the TURF option sheet for 2001-2002; and `Personnel and Financial Management for Horticulture' was created and approved in 2005. In a 2000 alumni survey, 100% of responding, employed Horticulture alumni (19 of 19) rated their internship as helpful. The program has worked well and has contributed to student success.
SUCCESSFUL INTERSPECIFIC HYBRIDIZATION BETWEEN Kalmia angustifolia VAR. caroliniana (SMALL) FERNALD AND Kalmia latifolia L.
Authors: Ballington J.R.
Published: June 2019

The genus Kalmia L. is endemic to North America. Kalmia latifolia is the best known species in the genus. It is a rounded evergreen shrub to small tree that ranges from northern Florida to New England. Flower color varies from white to pink, but at lower elevations in the southeastern U.S., pink flowers quickly fade to white. It is a diploid species with 2n = 2x = 24 chromosomes. Kalmia angustifolia var. caroliniana only occurs in the southeastern US. It is a thin upright evergreen shrub to 1.5 m tall. Flower color is either light pink or rosy purple, and the flower pigments appear to be heat stable. It is also diploid. Kalmia latifolia has not crossed readily with any other Kalmia species to date, but a small number of hybrids have been produced. The objective of the present study was to intercross K. angustifolia var. caroliniana with K. latifolia to attempt to develop color stable pink flowered Kalmia hybrids for warm climates. The crosses were made at Cary, N.C., from late April through mid May and included two clones of each species. Only one parental combination was successful and involved a rosy purple form of the former species. With this cross 15 mature seed capsules resulted from 38 pollinations. Numerous seedlings initially germinated, of which about 15% were albinos. Only 38 seedlings survived to transplanting. Thirty seedlings remain relatively vigorous 8 months after potting and are phenotypically intermediate between the parents. Their potential will depend on their ornamental characteristics once they reach maturity.
EVALUATION OF SCARIFICATION PERIOD AND GENOTYPE ON BLACKBERRY SEED GERMINATION
Authors: Cotner Stanta , Clark John R. , Stafne Eric T.
Published: June 2019

A study was conducted in the Winter–Spring 2004 to evaluate the effects of seed (pyrene) scarification period on blackberry (Rubus L. subgenus Rubus) genotypes that had a range of seed weights. The study was done in an attempt to identify optimum scarification period for variable seed weights for the purpose of increasing germination of blackberry seeds produced from hybridizations in the Arkansas blackberry breeding program. Scarification treatments of 1, 2, or 3 hours were used on 14 genotypes. Seeds were then stratified for 3.5 months and sowed on a commercial potting medium in a heated greenhouse. Germinating seedlings were counted over a 15-week period and total germination determined. Data analysis indicated significant genotype effect on germination but no scarification treatment nor genotype × scarification treatment interaction significance. The results indicated that scarification period did not affect germination and varying this period predicated on seed weight was not beneficial based on the genotypes used in the study.
FOLIAR DAMAGE OF BLACKBERRIES AND BLUEBERRIES BY JAPANESE BEETLE (Popillia japonica)
Authors: Stafne Eric T. , Clark John R. , Johnson Donn T. , Lewis Barbara A.
Published: June 2019

Since 1997, populations of Japanese beetle have settled into some of the major urban areas of Arkansas, especially Little Rock and Northwest Arkansas, due to transported turf and nursery material. Experimental trials at the University of Arkansas Agricultural Research and Extension Center, Fayetteville have sustained significant damage due to the increasing Japanese beetle population. Plantings of blackberries and blueberries were rated for feeding damage. Significant differences were observed among genotypes of both crops. Mean damage ratings varied from 0.6 to 4.0 for the blackberries and 1.2 to 3.5 for the blueberries. As evidenced by the mean damage ratings, some resistance or tolerance is present within these populations and may be exploited for improvement.
PHYTONUTRIENT EVALUATION OF STRAWBERRIES FROM FIELD AND GREENHOUSE PRODUCTION ENVIRONMENTS
Authors: Takeda Fumiomi , Lester Gene , Chandler Craig , Perkins-Veazie Penny , Prior Ronald
Published: June 2019

Fresh strawberries (Fragaria ×ananassa Duch) are readily available throughout the year with several new cultivars being successfully grown in diverse environmental conditions (e.g., field and greenhouse). Consumption of strawberries with higher nutritive values and antioxidant activity may contribute to improved human wellness. Phytonutrient contents and antioxidant activity was measured as oxygen radical absorbance capacity (ORAC) were assayed in berries (`Camarosa', `Diamante', and `Gaviota') sampled in January, February to March, and April to May from fields in Plant City, Fla., and Oxnard, Calif., and from a greenhouse in Kearneysville, WV. Strawberry cultivars varied in skin color, soluble solids, total phenolics, and anthocyanins, ascorbic acid, folic acid, and ORAC activity. Response to environment was cultivar dependent. All phytonutrient constituents were lower in `Diamante' berries compared to `Camarosa' and `Gaviota'. For all cultivars, berry ORAC activity declined as TSS increased, and ORAC activity was coincident with phenolic content. ORAC activity in berries fruit harvested from plants grown in a temperature-controlled greenhouse did not change during the January to May sampling period. For `Gaviota', ORAC activity in greenhouse-produced berries was the same as that of field-produced berries. Whereas greenhouse vs. field-gown `Camarosa' and `Diamante' berries ORAC was higher and lower respectively. These findings demonstrate that the environmental conditions in greenhouses in Kearneysville, W.Va., from winter to spring are adequate for `Camarosa' and `Gaviota' color development, but not for `Diamante' strawberries. Of the three cultivars, only `Camarosa' was highly productive (1.2 kg berries per plant), even in the greenhouse. Berries were high in ascorbic acid, folic acid, phenolic acid, anthocyanins, and ORAC activity.
GAS EXCHANGE AND GROWTH OF TWO FIELD-GROWN MAPLE TREE SPECIES IN RESPONSE TO THREE REFERENCE EVAPOTRANSPIRATION BASED IRRIGATION REGIMES
Authors: Montague Thayne , Fox Lindsey
Published: June 2019

Recent droughts and depleted water tables across many regions have elevated the necessity to irrigate field-grown (FG) nursery trees. At the same time, ordinances restricting nursery irrigation volume (often without regard to plant water requirements) have been implemented. This research investigated gas exchange and growth of two FG maple tree species (Acer × freemanii `Autumn Blaze' and A. truncatum) subjected to three reference evapotranspiration (ETo) irrigation regimes (100%, 60%, and 30% of ETo) in a semi-arid climate. During Spring 2002, nine containerized (11.3 L) trees of each species were field planted in a randomized block design. Each year trees were irrigated through a drip irrigation system. During the first growing season, all trees were irrigated at 100% ETo. Irrigation treatments began Spring of 2003. Gas exchange data (pre-dawn leaf water potential and midday stomatal conductance) were collected during the 2003 and 2004 growing seasons and growth data (shoot elongation, caliper increase, and leaf area) were collected at the end of each growing season. For each species, yearly data indicates irrigation regime influenced gas exchange and growth of these FG trees. However, it is interesting to note gas exchange and growth of these FG maple trees were not necessarily associated with trees receiving the high irrigation treatment. In addition, it appears the influence of irrigation volume on the growth of these FG trees is plant structure and species specific. Our data suggests irrigation of FG trees based upon local ETo measurements and soil surface root area may be a means to conserve irrigation water and produce FG trees with adequate growth. However, continued research on the influence of reduced irrigation on FG tree species is needed.
VARIABILITY FOR ANTIOXIDANT ACTIVITY IN THE U.S. COWPEA [Vigna unguiculata (L) WALP.] CORE COLLECTION
Authors: Nzaramba M.N. , Scheuring Douglas C. , Miller J. Creighton
Published: June 2019

Antioxidants are important to human health, as they are responsible for reduced risk of diseases such as cancer, hence motivating researchers to examine crop plants for available antioxidant compounds. There is also increasing interest in the use of antioxidants from plants instead of synthetic products. In order to evaluate variability of antioxidant activity (AOA) in cowpea, 697 cowpea accessions from the U.S. Cowpea Core Collection obtained from the Regional Plant Introduction Station, Griffin, Ga., were analyzed for AOA expressed as μg trolox equivalents/gdw. Two grams of dry seed from each accession were ground, extracted in methanol and analyzed for AOA using the free radical, 2,2-Diphenyl-1-picrylhydrazyl (DPPH), method. A large variation in AOA within the core collection, ranging from 1859 μg·g–1 dw (PI 180355, pigmented seed coat) to 42.6 μg·g–1 dw (PI 583100, cream seed coat), was observed. A least significant difference of 131.5 (p =0.05) was obtained. Higher AOA was manifested by accessions with pigmented seed coats. Accessions that were speckled, striped or had a pigmented eye were moderate in AOA, while the cream types were generally low. Variability in AOA observed among cowpea accessions suggests that breeding for high AOA can be successfully conducted. Accessions with high AOA could also be used to extract antioxidants for industrial purposes. Some accessions were a mixture of various colors and patterns, making it difficult to classify them into a particular category. Therefore, there is need to ensure purity of these accessions by ascertaining whether the mixtures are physical, i.e., combination of different varieties, or are composed of segregating material.
THESOUTHERN ORGANIC FRUIT PRODUCTION INITIATIVE: PROJECT GOALS, EXPECTED OUTCOMES AND PRELIMINARY FINDINGS
Authors: Friedrich H. , Rom C.R. , Johnson D. , Popp J. , Bellows B. , Savin M. , Miller D.
Published: June 2019

A multidisciplinary effort has been initiated between the University of Arkansas and the National Center for Appropriate Technology to identify production barriers, research and outreach needs, and market opportunities for sustainable and organic fruit in the Southern region. The goals of the project are to identify barriers of the organic system through focus group meetings with producers, processors and marketers, and to develop regional research and outreach projects to overcome these obstacles. Market development, organic fertilizer knowledge and organic pest management have been identified as areas that need research and outreach activities. Long-term outcomes are expected to increase sustainable and organic fruit production, provide opportunities for growers and consumers, and encourage local economic development in the Southern region.
MARKETING FEASIBILITY STUDIES OF DIFFERENT SUBSTRATE MIXES FOR RESIDENTIAL USE
Authors: Kaiser Kris-Ann , Rothenburger Anne , Williams Dr. Pat
Published: June 2019

Murray State University was asked to compare different amendment percentages of worm castings incorporated into a substrate and two different soilless substrates for bedding and vegetable production by Ferry-Morse Seed Company. Both studies were performed at Murray State University's Pullen Farm Greenhouse Complex during fall 2004. Lycopersicon esculentum `Early Girl' was chosen to represent the vegetable plant category because of consumer popularity. Amendment percentages of 0%, 10%, 20%, and 30% of worm castings were incorporated into a soilless media substrate for Treatment 1. Treatment 2 was the same with the addition of soluble fertilized when plants were watered. Visual differences were found between Treatments 1 and 2. Zinnia elegans `Giant Cactus' were grown from seed to test chlorophyll levels, germination rates, and root:shoot ratios in Jiffy Professional Seed Starter Mix Plus and Ferry-Morse Seed Starter Mix. Statistically significant differences were found in dry root and shoot weights, along with leaf chlorophyll levels.
CRITERION DEVELOPMENT FOR DELIVERING WEB-BASED PLANT IDENTIFICATION COURSES AT MURRAY STATE UNIVERSITY
Authors: Horne Jason , Williams Dr. Pat
Published: June 2019

Murray State University is developing an on-line delivery for the four plant identification courses offered in the horticulture option program. Reasons for developing this are to provide more efficient use of limited faculty time, to utilize new technologies in the delivering of courses, and to provide an interactive teaching assistance to students outside of class. The American Society for Horticultural Sciences (ASHS) was contacted for a listing of universities in the United States that offered horticulture programs. E-mails were sent to 109 universities and 44 surveys were received for a 40.4% return rate. None of the responding universities were using new technologies in the form proposed by MSU. Of the respondents, 27.3% were interested in a course of this type and thought it was a good idea to pursue whereas 11.4% were not interested in developing a course and 15.9% said a course of this kind would not have applications in their universities. Currently 25% are using computer-aided delivery for their horticulture courses. Macromedia Dreamweaver MX is being used for its versatile and accessible format over current Blackboard PowerPoint options.
PRELIMINARY FINDINGS ON PRODUCING ORGANIC VIDALIA ONIONS
Authors: Boyhan George E. , Hicks Raymond , Hill C. Randell
Published: June 2019

There has been interest in producing Vidalia onions organically among both conventional and organic growers. In the 2000–01 season we began to look at producing onions organically. Starting with conventionally produced transplants that were transplanted at standard commercial spacings on beds prepared with 10.2–15.2 cm of incorporated compost and 2,802 kg·ha–1 rate of fresh poultry litter. This was sidedressed with an additional 2,500 less/acre (2,802 kg·ha–1) poultry litter. Yields were about half of conventional onion production. In 2002–03, production of organic transplants with 10.2 cm of incorporated compost with 2.24 t·ha–1 rate of poultry litter, which was followed by an additional sidedressing of 2.24 t·ha–1 rate of poultry litter resulted in similar findings. The weight of harvested transplants was about half that of conventionally produced transplants. In the 2002–03 and 2003–04 seasons various natural mulches were evaluated for weed control. They included wheat straw, oat straw, Bermuda hay, pine straw, and compost. None of these performed better than hand weeding and the wheat straw, oat straw, and Bermuda hay actually reduced yields apparently due to allelopathic effects. Finally in the 2003–04 season rates of poultry litter from 0–22.4 t·ha–1 were evaluated for transplant production with rates of 13.4, 17.9, and 22.4 t·ha–1

yielding plants comparable to conventional transplants. Work continues in the area of organic Vidalia onion production. One of the greatest challenge for future work will be finding a cost-effective and practical method of controlling weeds in transplant production.
DIRECT SEEDING VIDALIA ONIONS
Authors: Boyhan George E. , Diaz-Perez Juan Carlos , Torrance Reid L. , Blackley Ronald H. , Hill C. Randell
Published: June 2019

The majority of Vidalia onions are produced as a transplanted crop. Seeding in high density plantings in September is followed 8 to 10 weeks later by transplanting to final spacing. This practice is labor intensive and expensive. Direct seeding would save on labor, cost, and time. Traditionally, transplanting has been done because of better winter survival, more uniform stands, and better irrigation management during seedling emergence. Beginning 5 years ago, we began evaluating direct seeding onions. Initially, seedstems (bolting) and lack of uniform stand establishment were the main problems. Sowing in September resulted in almost 100% seedstems and using a belt planter with raw seed resulted in poor singulation for uniform stand establishment. Mid-October ultimately proved to be the best time for sowing Vidalia onion seed. Earlier sowing resulted in more seedstems and later planting did not give the plants sufficient time to grow resulting in later stand loss during cold winter temperatures. Using polymer coated seed and a precision vacuum planter resulted in uniform, even stand establishment. Fertilizer requirements are almost half with direct seeded onions compared to transplanted onions with a reduction in the need for fungicides and herbicides. We have established direct seeded onions both with drip irrigation and overhead irrigation. There was concern that center-pivot irrigation would not be able to sufficiently irrigate fields during seedling establishment with the frequent hot fall days we experience. Since this work was initiated several growers have successfully produced direct seeded onions under center-pivot systems. Direct seeding Vidalia onions requires attention to detail because there is only one opportunity to get it right. Timing is also critical particularly with planting date and herbicide application.
SAFETY AND EFFICACY OF COMPOSTED BROILER LITTER IN MISSISSIPPI VEGETABLE PRODUCTION
Authors: Evans W.B. , Vizzier-Thaxton Y. , Hudson P. , Paridon K.
Published: June 2019

Mississippi is one of the nation's largest broiler litter producing states. Interest in using litter and other organic waste products, such as compost, in horticultural systems is increasing in the state and region. The objective of this research was to determine the influences of composted broiler litter (CBL) on three aspects of vegetable crop productivity: growth and yield, microbiological safety, and mineral nutrition. This report focuses on the first two objectives. Compost was made in a covered, turned windrow for a blend of broiler litter and hardwood sawdust. Responses to CBL were tested in two vegetables: collard (Brassica oleracea var. Acephala) and tomato (Lycopersicon esculentum). Rates of CBL ranged from 0 to 5 tons/acre, preplant incorporated in a randomized complete block design with four replicates for each species in two separate experiments in 2004. Testing of the CBL, the soil after application, leaves, and harvested organs found no significant influence of CBL on pathogenic microbe concentrations. At each of five sampling dates through commercial crop maturity, collard (Brassica oleracea var. Acephala) fresh and dry weight per plant increased linearly with CBL applications up to 5 tons/acre. Tomato (Lycopersicon esculentum) shoot fresh weight increased with increasing CBL applications at each sampling date. Marketable fruit yield increased linearly with increasing CBL applications. Total fruit yield response to CBL was best described by a quadratic equation.
USING COVER CROPS TO IMPROVE VEGETABLE PRODUCTION IN SOUTH FLORIDA
Authors: Olczyk Teresa , Li Yuncong , Klassen Waldemar , Wang Qingren
Published: June 2019

Summer cover crops can improve soil fertility by adding organic matter, supplying nutrients through mineralization, reducing nutrient leaching, and improving soil water and nutrient holding capacity. Other benefits include weed suppression and reduction of soil parasitic nematodes. A series of field experiments have been conducted at the UF IFAS Tropical Research and Education Center in Homestead, Florida to evaluate several summer cover crops for use in vegetable production in South Florida followed by field demonstrations conducted in the growers' fields. Best performing cover crops were legumes: velvet bean (Macuna deeringiana) and sunn hemp (Crotalaria juncea L. `Tropic Sun') providing 13 and 11 Mt of dry matter/ha, respectively. Sunn hemp supplied 330 kg N/ha followed by velvet been with 310 kg N/ha. Traditional summer cover crop sorghum-Sudan produced 4 Mt of dry matter/ha and retained only 36 kg N/ha. In addition Sunn hemp significantly reduced soil parasitic nematodes for successive crops. Limitations in use of Sunn hemp by more vegetable growers in South Florida include cost and availability of seeds.
ORGANIC TOMATO PRODUCTION IN OKLAHOMA
Authors: Roberts Warren , Edelson Jonathan , Bruton Benny , Shrefler Jim , Taylor Merritt
Published: June 2019

Plots were established at the Lane Agricultural Center in Lane, Okla., in 2003 for the purpose of conducting research in certified organic vegetable production. A field was selected that had been in pine timber since 1985. The field was cleared, plowed, disked, and land-planed. To establish a baseline for future reference, soil samples were collected on a 30 × 30 ft grid. Lime was added to adjust the pH. Poultry litter was added to the field as a fertilizer, and was incorporated by disking. Turnips were grown as a cover crop during the winter of 2003–04. In Spring 2004, the field was divided into four equal sections, which were planted with either tomatoes, sweet corn, watermelons, or southern peas. Tomatoes were planted using both determinate and indeterminate types. Plants were selected based on reported properties of interest to organic growers, such as disease resistance, pest resistance, or heat-set capabilities. The cultivars with greatest yield were Sunny, Solar Set, Classica, Sun Leaper, and Mountain Fresh. Visual disease ratings were taken throughout the season. Copper sulfate was used as a fungicide. The cultivars with the lowest disease ratings were Amelia, Peron, Celebrity, Florida 91, and Mountain Fresh. The major insect pest throughout the season was aphids. Aphid counts reached 6.9 aphids per leaf on 11 June. Two applications of AzaDirect, a neem extract, reduced aphid populations to 1.0 aphid per leaf on 17 June, 0.1 aphid per leaf on 25 June, and 0 aphids on 9 July.
FUNGICIDE APPLICATION FREQUENCIES FOR POTATO LATE BLIGHT (Phytophthora infestans) MANAGEMENT IN THE DOMINICAN REPUBLIC
Authors: Santos Bielinski M. , Gilreath James P. , Rodriguez Persio R.
Published: June 2019

Field trials were conducted in Constanza, Dominican Republic to determine the most effective fungicide application programs against potato late blight, and the cost component associated to those programs. Fungicide programs were: a) chlorothalonil (1.0 kg a.i./ha) every 5, 8, 11, 14 or 17 days; b) chlorothalonil rotated with metalaxyl (1.5 kg a.i./ha) every 5, 8, 11, 14 or 17 days; c) mancozeb (1.5 kg a.i./ha) every 8 days (grower standard); and d) a nontreated control. Examined data indicated that the highest `Granola' marketable tuber weights were obtained with the rotation of metalaxyl and chlorothalonil applied every 5, 8 or 11 days (14, 9 or 6 applications/season). This same rotation every 5 or 8 days (14 or 9 applications/season) was the most effective controlling late blight. There was no correlation between disease severity and marketable yield. For the cost components, the fungicide rotation applied every 11 days reduced application costs by 29%, in comparison with applications every 8 days.
DIFFERENTIAL PURPLE NUTSEDGE (Cyperus rotundus) PENETRATION THROUGH MULCH FILMS
Authors: Santos Bielinski M. , Gilreath James P.
Published: June 2019

Purple nutsedge can easily penetrate polyethylene mulch films. However, there are no reports on possible differences among mulch films. Because of this situation, field trials were conducted in Ruskin and Bradenton, Fla., during 2002 and 2003. In Spring 2002, the treatments were a) no mulch, b) black Pliant High Barrier mulch, and c) green Klerk's Virtually Impermeable Film (VIF). In Spring 2002, the films were a) black Pliant High Barrier, b) black IPM Bromostop, c) metallized Pliant, and d) green Klerk's VIF. The number of nutsedge emerged through the films was determined. No fumigants or herbicides were applied. Results indicated that the Klerk's VIF had the lowest nutsedge densities. No nutsedge control differences were found between the IPM Bromostop and the metallized Pliant films. These differences might be due to the physical properties of the films, including stretching and thickness.
EFFICACY OF DRIP-DELIVERED HERBICIDES FOR WEED CONTROL IN TOMATO IN PUERTO RICO
Authors: Santos Bielinski M. , Gilreath James P. , de L. Lugo Maria , Rivera Luis E.
Published: June 2019

A field study was conducted in Gurabo, P.R., to examine the potential of drip-applied herbicides for weed control in polyethylene-mulched tomato. The herbicide treatments were a) metolachlor at a rate of 1.1 kg a.i./ha; b) napropamide at 2.2 kg a.i./ha; c) pebulate at 4.5 kg a.i./ha; and d) trifluralin at 0.8 kg a.i./ha. A nontreated control was added. Each herbicide plot was split in two application methods: preemergence application and through the drip lines with 100 m3 water. In both cases, herbicides were delivered three weeks before tomato transplanting. There was no significant difference between the two delivery methods. Metolachlor showed the best control of broadleaf weeds (>80%) and highest tomato fruit yield. Applying herbicides through the drip lines is a viable alternative in mulched tomato.
TOMATO CULTIVAR EVALUATION IN ARKANSAS
Authors: Williams D.R. , Andersen C.R. , Eaton S.E. , Martin L.W.
Published: June 2019

A fresh-market tomato trial was conducted in 2003 at two locations in Arkansas (Fayetteville and Kibler) to evaluate new and old tomato varieties of interest to home gardeners and farmers' markets. The observational trial consisted of 43 varieties, indeterminates and determinates. Heirloom tomatoes comprised a large portion of the trial due to increasing popularity. Heirlooms are unique and can be very eye-catching. There is immense variety in shape, size, and color. They can be large or small, many times the shape is irregular, and the fruits flawed (cracking, cat-facing, green shoulders). The fruit may not store or ship well; most are grown and sold locally. Some heirlooms are better than others. A few of the varieties that stood out in the trial were Costoluto Genovese, Abraham Lincoln, Dona, and Persimmon. Costoluto Genovese, a uniquely ruffled red tomato, was the highest yielding variety at the Kibler location. Fruit quality remained high even in the highest temperatures. One of the most promising was a orange variety called Persimmon, it produced large fruit and the plants provided excellent cover. Dona and Abraham Lincoln, both reds, yielded well and had good flavor. San Marzano and Arkansas 7985 were the best paste types. Arkansas varieties such as Bradley, Ozark Pink, and Arkansas Traveler 76 also did well. Brandywine varieties had low yields and lesser quality fruit. Green zebra, a green striped fruit with good flavor, yielded less due to Blossom End Rot. Cherokee Purple and Carbon were two from the purple/black category that did not do well; yields were low and the fruit cracked.
ORGANIC BLUEBERRY PRODUCTION AND OBSERVATIONS IN GEORGIA
Authors: Krewer Gerard , Stanaland Danny , Liburd Oscar , Larson Jerry , McWilliams Roosevelt , NeSmith D. Scott , Hepp Ruperto , Mullinix Ben
Published: June 2019

Georgia has an excellent window for organic blueberry production since much of the crop ripens ahead of production in the northern U.S. Major challenges facing Georgia organic blueberry growers are weed control, organic fertilization, insect control and disease control. A team of Georgia growers, extension agents and scientists are working together to solve these production problems. Since 2002 a series of experiments have been conducted on blueberry establishment and maintenance. Various mulch materials were tested. On young plants, pine straw produced the highest yields, but pine bark and landscape fabric were also successful. With the pine straw treatment, a respectable yield of 0.97 kg/plant occurred 24 months after planting. In addition, a bed shaper–plastic mulch layer was modified by developing a removable center. Using this system, beds are formed, plants are mechanically transplanted, plants are pruned to 75 mm, and plastic is then pulled over the stem. This produces a fairly tight fit around the stem and a nearly weed free system except for weeds growing from the edges. On mature plants, pine bark and wheat straw were tested. Wheat straw produced excellent weed control and improved blueberry growth in year one and two. However, pine bark mulch provided the best weed control in year three. Various organic burn down compounds such as vinegar, Xpress, Alldown, and Matran 2 were tested for winter weed control efficacy. In these trials Matran 2 was the most effective, and the product also performed well on woody weeds that were winter pruned, allowed to resprout and then treated. A propane torch was also tested, but discarded because of the fire hazard. Entrust insecticide was tested for thrips control and gibberellic acid for fruit set. Thrips populations were low, so no effect on fruit set was noted from Entrust. Gibberellic acid significantly improved fruit set.
STIGMATIC RECEPTIVITY AND POLLEN TUBE GROWTH IN RABBITEYE BLUEBERRY
Authors: Brevis Patricio A. , NeSmith D. Scott , Wetzstein Hazel
Published: June 2019

Effective pollination period (EPP) is the number of days during which pollination is effective to produce a fruit. The EPP is determined by ovule longevity, pollen tube growth rate and length of stigmatic receptivity. The objectives of this research were to establish the EPP of rabbiteye blueberry and to further the understanding of its limiting parameters. The experiments were conducted in growth chambers using blueberry plants of the cultivars Brightwell and Tifblue. Emasculated flowers were hand-pollinated at 0, 2, 4, 6, and 8 days after anthesis (DAA). Ripe fruit were harvested to record percentage fruit set. Stigmatic receptivity was evaluated as the number of germinated tetrads on the stigma 24 hours after pollination. Under day/night temperatures of 23/10 °C, the EPP was 7 days. Stigmatic receptivity was lowest on the day of anthesis and increased as flowers aged. Stigmatic receptivity was not positively correlated to fruit set, therefore, this parameter was not the most limiting factor of the EPP. Observations of pistils pollinated 3 DAA indicated that the fastest growing pollen tubes reached the bottom of the style 2 to 3 days after pollination. Self-pollination resulted in normal pollen tube growth in the style and inside the ovary. Self-pollen tubes were seen penetrating the micropile.
TESTING POTENTIAL ALTERNATE METHODS OF BLOOM THINNING FOR APPLE IN VITRO
Authors: Bajwa Vikramjit , Rom Curt R.
Published: June 2019

Alternate bloom thinners are needed for apple are needed to replace compounds which can no longer be used or have production system limitations. The effects of 24 chemicals selected as osmotic agents, organic acids, oils, essential oils, or potential metabolic agents and their properties of pH, electrical potential (EP) and water potential were tested in vitro on `Gala' apple pollen germination, tube growth and pistil damage. Solution concentrations of 0%, 0.25%, 0.5%, 1%, 2%, 5%, and 10% were prepared and solution pH, EP, and water potential measured. To test affects on germination, pollen was placed on agar germination media in petri dishes and then treated with 10: l of chemical solution. Percentage pollen germination and tube growth was calculated 4, 12, and 24 h after treatment. Excised pistils from forced flowers were placed on glass filter papers saturated with chemical solution. Pistil damage was visually, subjectively rated for damage indicated by discoloration 24 h after treatment. Effects of solution pH, EP and water potential on pollen germination, tube growth and pistil damage was significant with pH less than ∂4.0 or greater than ∂10.0, EP > 200mv, or water potential less than ∼4.0MPa inhibited pollen germination, growth, and killed pistils. Several chemical had apparent metabolic effects beyond the chemical effects mentioned above. In vitro tests were correlated to in vivo field tests in other studies indicating the use of pollen and pistil in vitro as a useful model for screening potential alternative thinning agents.
THE SOUTHERN ORGANIC FRUIT INITIATIVE: A NEW MULTISTATE, MULTI-DISCIPLINARY COOPERATIVE PROJECT TO STIMULATE RESEARCH, OUTREACH AND PRODUCTION IN THE SOUTHERN REGION
Authors: Rom Curt R. , Friedrich H. , Johnson D. , Popp J. , Bellows B. , Savin M. , Miller D.
Published: June 2019

Fruit production in the Southern region has declined in the last several decades. Further, although certified organic fruit production has increased significantly in other regions of the US in the past decade, there has been very little growth of that industry in this region. It is presumed that the lack of production is based upon the lack of research, out-reach, and science-based information available to growers which make organic production possible. Based on planning grant funding from the Southern IPM Center program and the Sustainable Agriculture Research and Education program a Southern Organic Fruit Working Group is being formed. The projects are collaborative efforts of horticulturists, entomologists, plant pathologists, soil scientists, and agricultural economists in Arkansas, Georgia, Kentucky, North Carolina, South Carolina, and Tennessee. In each state, a coordinator is hosting stake-holder focus groups of producers, marketers, processors, extension workers, consultants, organic certifiers, etc. The purpose of focus group meetings is to identify challenges and opportunities in production and marketing organic fruit, especially apples, blackberries, blueberries, and peaches, in the Southern Region. Coordinators are combining findings from state focus group meetings to establish priorities for research and outreach to support organic production, and will work collaborative to addresses those priorities. Because of the similarity in climate, geography and demographics of growers and markets among the states of the region, this is a project best addressed as a regionally collaborative effort.