bluuebunny/crossref_metadata_2025 huggingface dataset:
628 (PS 3) CORNUS FLORIDA `OZARK SPRING', A NEW, HARDY DOGWOOD
Authors: Pair John C. , Pellett Harold
Published: April 2024

The importance of regional adaptation of native plants is apparent in the selection of cultivars, especially in Cornus florida L., which grows in specific geographic areas of the United States where climate, soil and site characteristics are favorable. Selected from a seedling population in the western portion of the native range, `Ozark Spring' was compared with cultivars from other regions. Growth and flowering were determined under moderately stressful conditions in south central Kansas. The selection was one of the few which flowered following -30°C (-23°F) during the winter of 1982. Hardiness was confirmed at -29 to -31°C by University of Minnesota freezing tests. Performance of `Ozark Spring' has been superior to other cultivars in growth and bract development when planted in more exposed sites. The cultivar is expected to perform best in the Ozark region of Oklahoma, Arkansas, Missouri and eastern Kansas.
629 (PS 3) ROOTING AND SUBSEQUENT GROWTH OF SUPERIOR LACEBARK ELM SELECTIONS BY HARDWOOD AND SOFTWOOD CUTTINGS
Authors: Pair John C. , Shelton Michael
Published: April 2024

Numerous cultivars of Lacebark elm (Ulmus parvifolia Jacq.) have recently been introduced which are produced vegetatively. Conventional propagation is usually by softwood cuttings under intermittent mist which is quite successful. Softwood cuttings taken off two mature specimen trees stuck in May and June rooted 73 and 93 percent respectively at 10,000 ppm IBA but required overwinter protection prior to lining out the following season. Hardwood cuttings of numerous selections, stuck in perlite: peat (70:30 v/v) over bottom heat at 21°C in a cool greenhouse rooted 60 to 100 percent at 10,000 and 20,000 ppm. Cuttings from winter prunings were taken on February 4, potted by March 12, lined out May 23 produced 69 to 97 cm of growth the same season. The latter procedure offers a low input method of propagation which has several advantages over using softwood cuttings.
630 (PS 3) PRAIRIE PLANT SEED AND SEEDLING IDENTIFICATION
Authors: Bohnen J.L. , Hanchek A.M.
Published: April 2024

Photographic resource materials to assist in identification of seeds and seedlings of grasses and forbs native to Minnesota prairies are being developed as part of a grant from the Legislative Commission on Minnesota Resources. Native plant materials are being used for habitat improvement, roadside vegetation, and landscape plantings throughout Minnesota. Seeds were obtained from producers or collected from prairie remnants. Seed photographs were taken with a Wild Leitz stereomicroscope and camera unit using Kodak EPY 64T film. Magnification was 6.5X, 10X, or 16X based upon seed size. Seedlings were photographed with one or two true leaves using Kodak EPY 64T film with a Nikon FM2 camera with a 55 mm micro Nikkor macro lens and an extension tube when necessary. Nondestructive sampling using photographic techniques provides a relatively quick and inexpensive means of recording information on potentially rare species. The color pictures and slides developed in this project provide an effective tool for educators, producers and land managers to easily distinguish between seeds and seedlings of valuable native plants and those of weedy species undesirable in restoration projects or cropping systems.
ABSORPTION, TRANSLOCATION, AND METABOLISM OF DITHIOPYR IN SELECTED WEED SPECIES.
Authors: Setyowati Nanik , Weston Leslie A.
Published: April 2024

Field studies have shown that dithiopyr has potential as a herbicide in ornamental nursery crops. Previous work has shown that certain weeds differed considerably in their tolerance to dithiopyr, both in the field and in the greenhouse. Four weeds were selected on the basis of these studies; large crabgrass and velvetleaf, both susceptible, and barnyardgrass and ivyleaf morningglory, tolerant species.

Root uptake was assessed in these four species by treating seedlings with 0.5 μCi of 14C-labelled dithiopyr dissolved in half strength Hoaglands solution. Whole plants were sampled at 12, 24, 48 and 96 hour after treatment (HAT) and plants were separated into roots and shoots. Dithiopyr levels and polar metabolites were measured after methanolic extraction of plant parts. Insoluble 14C levels were measured after biological oxidation. At 12 HAT, TLC and HPLC separation of extracts showed no detectable metabolites of dithiopyr. By 24 HAT, two polar metabolites were detected in both root and shoot extracts of all species. Total 14C and polar metabolites increased in roots and shoots over time. Species differences in total 14C uptake and metabolism were noted, potentially contributing to dithiopyr selectivity differences.
SPORE VIABILITY AND GERMINATION OF THE ENDANGERED ALEUTIAN SHIELD-FERN, POLYSTICHUM ALEUTICUM
Authors: Holloway Patricia S. , Boyd David J.
Published: April 2024

Research was initiated in 1990 to study spore viability, spore germination in vitro, and methods of controlled environment culture for the endangered Aleutian shield-fern, Polystichum aleuticum. Examination of spores using scanning electron microscopy revealed from 24% to 78% deformed and possibly nonviable spores per plant. Normal spores germinated in 30-45 days on both Knop's solution and Hoagland's No 2 solution in aseptic culture. Germination was most rapid on cultures with less than 6 g/1 agar. Cultures with no agar were susceptible to contamination by algae, and sporophyte losses during transfer to greenhouse media were high. Germination rate and subsequent appearance of the first leaf stage did not differ significandy within a medium pH range of 4.7 to 7.0. Spores exhibited a thermodormancy at 25°C, but germinated well at 18°C and required light for germination. Sporophyte transfer from aseptic culture was most successful after true fronds beyond the first leaf stage had developed. A commercial bedding plant mix composed of Sphagnum sp. peat and perlite provided an optimum rooting medium for the ferns.
640 (PS 4) MAXIMIZING SHOOT REGENERATION FROM ANTHER CULTURES OF STRAWBERRY (Fragaria ×ananassa Duch.)
Authors: Owen Henry R. , Miller A. Raymond
Published: April 2024

A sequential study was undertaken to optimize the cultural conditions for potential tetrahaploid plant regeneration from anthers of `Chandler', `Honeoye', and `Redchief' strawberries. A comparison of auxins (IAA/NAA), cytokinins (BA/BPA/KIN) and carbohydrates (suc/glc/mal) showed highest regeneration with 2mg/l IAA, 1mg/l BA and 0.2M glc in agar-solidified MS medium after 60d (30d darkness + 30d 16h white light photoperiod). When comparing MS. Nitsch & Nitsch, and H1 (a new formulation based on the anther culture literature) media containing IAA/BA/glc solidified with Phytagar® or Gelrite®, highest regeneration occurred with H1 with Gelrite. Lastly, Fe-EDTA in H1 medium with IAA/BA/glc yielded more shoots than H1 medium containing Fe-Metalosate®, and anthers cultured in darkness for 30d followed by 30d in white light produced more shoots then those cultured in white or yellow light (16h photoperiod) for the initial 30d. Hence, the optimum regeneration medium and conditions for shoot regeneration from anthers of these 3 cultivars was H1 containing 2mg/l IAA, 1mg/l BA, 0.2M glc, Fe-EDTA, and Gelrite, followed by incubation in darkness for the first 30d. Although differences were noted for regeneration efficiency between cultivars, initial chromosome counts confirmed that tetrahaploids (n=4x=28) were obtained.
641 (PS 4) CALLOGENESIS AND ORGANOGENESIS AS AFFECTED BY THE ORIENTATION AND SCARIFICATION OF LEAF DISC APPLE EXPLANTS ON THE MEDIUM
Authors: de L.Fortes Gerson R. , Teixeira Silvio L.
Published: April 2024

The aim of this work was to investigate the effect of orientation and scarification of apple leaf discs on the callogenesis and organogenesis. Leaf discs were collected from 4-months old apple seedlings cv.Hawai along the midrib of the first pair of basal leaves. The treatments included the touching of the medium with the abaxial and adaxial surface and scarification and no-scarification of midribs. The leaf discs being placed in test tubes contained 10ml of a HS medium added to vitamin B5 in mg/l:BAP (3,0); NAA (0.30); myo-inositol (100.0) glycine (2.0). Sucrose was added to the rate of 30.0g/l and agar 6.0g/l. After three weeks in dark condition and one month more in 16-hour photoperiod in a growth room at 23–25°C; 2000–2500 lux, the experiment was evaluated. Callus promptly formed at the cut surfaces and was both influenced by the surface touching the medium and scarification. Adaxial surface allows a better callus formation (100.0%) whereas abaxial ones promoted it partially (61.2%). Scarification did not improve the % of callus culture formed. No adventitious buds were observed and it was claimed to be due to the explants age. The better performance for the adaxial explants was due to the palisade parenchyma which is the last tissue to cease growth and cellular division
643 (PS 4) MICROPROPAGATION OF WHITE TARO (COLOCASIA ESCULENTA VAR. ESCULENTA CV. PIKOKEA, POLOLU, NIHOPUU, AND HAUKEA
Authors: Martin Susan P. , Bobisud Carol A. , Sekioka Terry T.
Published: April 2024

Axillary or apical meristem explants of white taro, a potential hypoallergenic food, were used. `Pikokea,' `Pololu,' `Nihopuu,' and `Haukea' varieties were taken directly from the field. Disinfestation method was a 60-minute wash under running tap water, followed by a 40-minute soak in 10% commercial sodium hyperchlorite bleach, and then a double rinse in sterile water. Buds were excised and placed in sterile water. These were put in a 70% ethanol dip, followed by a sterile water rinse, a 30-minute soak in 5% commercial sodium hyperchlorite bleach, and three sterile water rinses. Modified Murashige and Skoog media containing combinations of 5 and 10 uM indole-3-acetic acid (IAA) with 5 and 10 uM 6-benzylaminopurine (BAP) were used. A treatment of no growth regulators was included. Shoot development resulted in almost all explants in every treatment.
646 (PS 4) PHOTOSYNTHETIC PHOTON FLUX AND UV-B EFFECTS ON ETHYLENE EVOLUTION, PROLIFERATION, AND LIPID CONTENT OF `DOYENNE D'HIVER' PEAR IN VITRO
Authors: Predieri S. , Krizek D.T. , Mirecki R.M. , Norman H.A. , Zimmerman R.H.
Published: April 2024

In vitro-grown shoots of `Doyenne d'Hiver' pear (Pyrus communis L.) were maintained for 7 days on 16-h photoperiods at photosynthetic photon fluxes (PPF) of 90, 180 or 270 μmol·m-2·s-1 and irradiated 6 h per day midway through the photoperiod at 0.2 (-UV-B) or 12.0 (+UV-B) kJ·m-2·d-1 of biologically effective ultraviolet-B (UV-BBE) radiation. Increased ethylene production from UV-BBE-treated shoots as compared to the control was recorded after 24 h in cultures grown under 90 and 180 μmol·m-2·s-1 and after 72 h in shoots grown under 270 μmol·m-2·s-1; PPF level had little effect on amount of ethylene evolved. Proliferation was highest at 270 μmol·m-2·s-1, but UV-BBE decreased proliferation and increased apical necrosis. UV-BBE treatment increased lipid peroxidation after 24 h based on malondialdehyde (MDA) determination, but thereafter had no consistent effect on MDA. UV-BBE exposure slightly decreased the monogalactosyldiacylglycerol/digalactosyldiacylglycerol ratio during the initial 24 h, showing an effect on chloroplast membranes.
ISOLATION AND CULTURE OF DAYLILY MESOPHYLL PROTOPLASTS
Authors: Ling Jing-Tian , Sauve Roger J.
Published: April 2024

Mesophyll protoplasts were isolated from a diploid daylily (Hemerocallis cv. `Red Magic') by enzyme digestion with a solution containing 0.5% Pectolyase Y-23, Cellulase R-10 1.0%, Driselase 0.1%, Sorbitol 0.6M and half-strength MS inorganic salts at 60 rpm for 4 h. The protoplasts underwent sustained division to produce multicellular colonies on a MS medium supplemented with 0.5 mg/l NAA and 0.5 mg/1 BA. The optimal plating density for cell division was 5 × 104 cells per ml. Cultures grown in agarose-bead media resulted in higher plating efficiencies that of those in solidified or liquid media. Under the above conditions, formation of colonies occurred in 8 to 11% of the cultured protoplasts. Research is in progress for the production of callus from protoplast-derived colonies and for the generation of plantlets from callus.
656 (PS 4) MICROPROPAGATION OF COCOYAM (XANTHOSOMA SAGITTIFOLIUM (L) SCHOTT)
Authors: Nyochembeng Leopold M. , Zok Simon
Published: April 2024

Studies were conducted to improve the establishment medium and to induce multiple shoot formation for mass production of cocoyam. The addition of 1 mg/l isopentenyladenine to the basal B5 liquid medium enhanced regeneration and plantlet establishment. Multiple shoot formation was favored by 10 mg/l benzylaminopurine in the basal medium. Furthermore, the multiplication rate could be increased and the micropropagation process enhanced when 4 week old plantlets, rather than 6 week old, were used to induce multiple shoot formation. These results confirmed earlier findings on the effects of sequential application of growth regulators on organogenesis in cocoyam cultures. The impact of these results for mass propagation of this crop is discussed.
658 (PS 4) INFLUENCE OF PECAN SOMATIC EMBRYO MORPHOLOGY ON CONVERSION INTO PLANTLETS
Authors: Rodriguez Adriana P. M. , Wetzstein Hazel Y.
Published: April 2024

It has previously been shown that the induction medium influences embryogenesis and embryo morphology in pecan (Carya illinoensis). The objective of this study was to evaluate the effect of embryo morphology on germination and conversion into plants. Pecan somatic embryos induced on modified WPM with NAA or 2,4-D were categorized into three classes according to morphology: embryos with evident apex and well formed cotyledons; embryos with weak or no apex, with or without distinct cotyledons; and abnormal embryos. Embryos were given conversion-enhancing treatments which included cold treatment for eight weeks, followed by desiccation for five days. The embryos were then transferred to modified WPM with 10mg/l silver nitrate and 5mg/l gibberellic acid. The conversion of embryos was rated based on presence of leaflets and roots. Embryos germinated in all three classes. Conversion was markedly affected by embryo morphology; higher conversion rates were obtained with embryos which more closely resembled the zygotic morphology.
INFLUENCE OF AGAR AND AMMONIUM NITRATE ON TISSUE NITROGEN, CULTURE GROWTH, AND VITRIFICATION
Authors: Brand Mark H.
Published: April 2024

Shoot tips of Amelanchier were grown on Murashige & Skoog (MS) or Woody Plant (WP) medium containing 4.4 μM benzyladenine and 4, 6 or 8% Difco Bactoagar. Increasing agar concentration reduced culture fresh weight, dry weight, and vitrification, but increased tissue nitrate concentrations. The number of shoots produced per culture was unaffected by agar concentration. Overall, response to agar additions was similar for shoots on both WP and MS salts, although the magnitude of the response may have differed. Amelanchier shoots cultured on WP medium containing 4% agar and 10.5, 15.5, 20.9 or 25.5 mM nitrate showed a linear increase in culture fresh weight, culture dry weight, number of shoots per culture and number of vitrified shoots per culture as medium nitrate concentration increased. Nitrate and total nitrogen content of explants also increased linearly with increasing medium nitrate concentration. Although vitrification has been previously ascribed to elevated ammonium concentrations in culture media, it is possible that elevated medium and tissue nitrate levels may also play a role in vitrification.
PLANT REGENERATION AND TRANSFORMATION IN COREOPSIS LANCEOLATA
Authors: Nichols Joel T. , Wang Lijuan , Lee Chiwon W.
Published: April 2024

Leaf discs of Coreopsis lanceolata, when cultured on Murashige and Skoog (MS) medium supplemented with 10 μM benzyladenine (BA) and 1 μM naphthaleneacetic acid (NAA), produced shoots in four weeks. Shoots were often induced on the marginal tissues of the leaf discs without callus formation. The frequency and the number of shoots induced per leaf disc varied slightly when growth regulator combinations of 0.5-40 μM BA and 0-2 μM NAA were tested. Most shoots produced roots on the same regeneration medium after formation of 3 to 5 leaves. The rooted plants were established in soil within 3 months from initial culture. For genetic transformation, leaf discs were infected with Agrobacterium tumefaciens Strain LBA 4404 carrying both kanamycin resistance and β-glucuronidase (GUS) genes. Shoots were induced from these leaf discs on the regeneration medium containing 250 mg/liter kanamycin. The histochemical assay showed that the regenerated shoots were GUS positive.
667 (PS 4) IDENTIFICATION OF A NEW BENZYL ADENINE COMPOUNDPRODUCED DURING PETUNIA SHOOT ORGANOGENESIS
Authors: Auer Carol A.
Published: April 2024

Studies of benzyl adenine (BA) uptake and metabolism in Petunia leaf explants during shoot organogenesis revealed a novel BA conjugate. The new conjugate comprised up to 39% of the total pool of BA conjugates in two petunia lines and was associated with an increased shoot organogenic response when compared with a third petunia line which did not produce the conjugate. To identify the new compound, structural analysis was conducted using FAB mass spectrometry, two methods of carbohydrate analysis, UV absorption spectra and FTIR spectra. Experimental results identified the compound as 6-benzylamino-9-[O-glucopyranosyl-(1→3)-ribofuranosyl]-purine, a disaccharide conjugate of BA. Based on biological studies and similarity to other cytokinin conjugates, this disaccharide cytokinin conjugate may be part of the interconvertible pool of cytokinins active in shoot organogenesis.
670 (PS 5) COMPARISON OF TECHNOLOGIES FOR GROWTH REGULATOR APPLICATION TO ANNUALS
Authors: Gilbertz David A. , Oetting Ronald D.
Published: April 2024

Application by fixed-position mist blower (MB), air-assisted electrostatic sprayer (ES), hydraulic piston pump sprayer (PP) or hand-held compressed air sprayer (HH) was compared for growth regulator efficacy on Petunia hybrida `Polo Burgundy Star' and Tagetes erecta `Inca Orange'. Daminozide at 5000 mg/l (DM) or paclobutrazol at 75 mg/l (PB) was applied using PP or HH sprayers (high volume) at 200 ml/m2. ES (low volume) and HB (ultra low volume) sprayers were adjusted to provide an equivalent active ingredient of growth regulator per area. Growth of marigold was similar between the 2 growth regulators. Marigolds treated by either growth regulator averaged 92% of untreated plant height, except ES-treated plants which averaged 80%. ES-treated marigolds flowered 4 days later and had less top dry weight than plants in other treatments. Growth regulator-treated petunias averaged 90% of untreated plant height. Generally, there were few differences between petunias treated with DM or PB but the results showed some sprayer type by growth regulator interaction. Type of application was slightly more important for applying DM than PB to petunias.
672 (PS 5) PINE BARK-AND PEAT-BASED MEDIA INFLUENCE THE EFFECTS OF PACLOBUTRAZOL SPIKES ON `CELEBRATE 2' POINSETTIAS
Authors: Quarrels Jesse R. , Tant Jeffrey S. , Newman Steven E.
Published: April 2024

The objective of this study was to determine the influences of 8 commercial media, 4 peat-based and 4 pine bark-based, on the effects of paclobutrazol applied to the media of each plant at pinch in a spike formulation or as a drench (two weeks after pinch) to `Celebrate 2' poinsettias. The peat-based media were Baccto Grower's Mix, Baccto High Porosity Professional, Baccto High Porosity Professional with Bacctite, and Baccto Rockwool Mix. The pine bark-based media were Metro 360, 366, 700, and 702. Paclobutrazol was applied to the media at 10 treatment combinations (0, 2, 4, 6 and 8-0.05% spikes, 1 and 2-0.2% spikes, 1 0.08% spike, and 0.25 and 0.50 mg drenches in each 15 cm pot). Spike and drench formulations of paclobutrazol reduced plant size. Plants grown in the peat-based media were more sensitive to paclobutrazol than those grown in bark-based media. Stem length of those plants treated with paclobutrazol spikes was less than those treated with an equal amount of paclobutrazol as a drench in all media except the Rockwool Mix and Metro 702.
681 (PS 5) EVALUATION OF PELLETIZED SEWAGE SLUDGE FERTILIZER FOR GREENHOUSE PLANTS
Authors: Cox Douglas
Published: April 2024

In separate experiments 'First Lady' marigold (Tagetes erecta L.) and 'Selenia' New Guinea impatiens (Impatiens sp. hybrids) (NGI) plants in 0.5-liter pots of soilless mix were fertilized with water-soluble 20N-4.3P-16.6K (WS), controlled-release 14N-6.2P-11.6K (CR), or two types of heat-dried sewage sludge pellets (3N-1P-0.1K or 5N-1.3P-0.1K, ≈ 3mm dia.) (SP). All fertilizer treatments were calculated to supply the same amount of N in each experiment. The same volume of irrigation water was applied to all plants during each experiment. Leachate was analyzed for NH4-N and NO3-N at regular intervals and growth was measured at the end of each experiment. SP alone reduced N leaching an average of 54% compared to WS or CR alone, but did not provide adequate nutrition for marigold; symptoms of N deficiency and reduced dry weight were the result. However, SP alone caused no such effects on NGI. Marigold growth was increased and N deficiency symptoms were prevented by partially substituting SP with WS at 25% of total N supplied. The same treatment had no effects on NGI. Combining SP and WS in this manner resulted in little or no increase in N leaching over SP alone.
682 (PS 5) PHOSPHORUS LEACHING FROM POTTED POINSETTIA WITH LEACHING FRACTIONS OF 0, 0.2, AND 0.4
Authors: Ku Catherine S.M. , Hershey David R.
Published: April 2024

Single-pinched `V-14 Glory' poinsettias in 15-cm diameter pots of growing medium received constant liquid fertigation with 200 mg/L N from 100% NO3-N or 60% NO3-N:40% NH4-N, 8 or 23 mg/L P, and leaching fractions (LFs) of 0, 0.2, and 0.4 during a 13 week study. The total P applied via fertigation ranged from 43 mg at 0 LF to 303 mg at 0.4 LF. P leached with tap water from unplanted pots totalled 31 mg. The concentration of leachate P ranged from 0.2 to 46 mg/L. With 8 mg/L P, leachate P decreased from a mean of 35 mg/L initially to less than 4 mg/L after 30 days. The percentage of the applied P in the leachate at 8 mg/L P fertigation was 12% at 0.2 LF and 20% at 0.4 LF for both N sources. With 23 mg/L P fertigation these losses were 24% at 0.2 LF and 41% at 0.4 LF for 60% NO3-N plants but only 11% at 0.2 LF and 25% at 0.4 LF for 100% NO3-N plants. Across all treatments, the P in the shoot was partitioned as follows: 31% in leaves, 42% in bracts, and 28% in stems. Although plants receiving 23 mg/L P had a 41% higher P concentration in their shoots than 8 mg/L P plants, there were no differences in yield between the two P levels.
IRON DISTRIBUTION AND THE OCCURRENCE OF AN IRON PHYSIOLOGICAL DISORDER IN MARIGOLD
Authors: Albano Joseph P. , Miller William B.
Published: April 2024

The objective of this experiment was to study Fe distribution patterns in marigold (Tagetes erecia L., cv First Lady). Previous experiments have identified `First Lady' as an Fe-sensitive cultivar. Plants were grown in a commercial peat-based media. Treatments consisted of 0, 17.9 and 179 μM Fe-DTPA added to a modified Hoagland's solution. In the presence of excess Fe, `First Lady' developed a speckled pattern of chlorosis and/or necrosis of recently matured, primary leaves associated with downward leaf curl and/or cupping. Hereafter the disorder is referred to as “Bronze Speckle”. Plants treated with 179 μM Fe-DTPA developed symptoms of “Bronze Speckle” with symptom severity increasing with leaf age and Fe concentration. Plants of the 0 and 17.9 μM treatments did not develop “Bronze Speckle”, however Fe concentrations varied by treatment and tissue. Iron concentration in roots increased with Fe-DTPA treatment. Treatments had no effect on plant height or axillary and primary flower bud production.
698 (PS 5) DOES SIZE OF HARDWOOD CUTTING AND NUMBER OF BUDS AFFECT ROOTING SUCCESS OF ACTINIDIA ARGUTA?
Authors: Beyl Caula A. , Ghale Gokul
Published: April 2024

This work was conducted to determine if characteristics of the hardwood cutting (such as size of the cutting and the number of buds) could be correlated to rooting and subsequent development. Dormant wood of 13 cultivars of Actinidia arguta were cut into lengths which varied from 3.5-18 cm containing from 1-9 buds. After being treated with 0.3% indolebutyric acid, cuttings were then stuck into Oasis Rootcubes and placed under intermittent mist. Cultivars of Actinidia arguta included 74-46, 74-55, 124-40, 125-40, 127-40, 119-40-B. “Meader Male”, “Meader Female #1”, “Geneva #1”, “Ananasnaja”, “Michigan State”, arguta cordifolia 1563-51 and a New Zealand cordifolia selection. There was a significant effect of cultivar on number of roots, root grade, length of roots, and callus. All rooting parameters were highly correlated with length of the cutting and number of buds in active growth. Caliper was negatively correlated with only root grade.
WINTER ANNUAL LEGUMES AND GRASSES AS MULCHES FOR SUSTAINABLE AGRICULTURAL PRODUCTION OF FRESH-MARKET TOMATOES
Authors: Abdul-Baki Aref A. , Teasdale John R.
Published: April 2024

Hairy vetch, crimson clover, and rye, separately or in combination, were grown in the fall as cover crops and mowed in the spring to form an organic mulch in a no-tillage sustainable agricultural system for production of fresh-market tomatoes (Lycopersicon esculentum Mill, cv `Sunny'). Fruiting earliness, yield, and size were compared between the organic mulch treatments and those under bare soil, paper and black polyethylene mulches. Fruiting was about 9-10 days earlier under black polyethylene mulch than all other treatments. Total marketable yields (t·ha-1) under the mulch treatments were: hairy vetch, 85; hairy vetch plus rye, 69; crimson clover, 66; black polyethylene, 44; bare soil, 36; and Horto paper, 30. Average fruit size was significantly larger in all organic mulch treatments than in bare soil, Horto paper, and black polyethylene mulches. Early growth of tomato plants was highest with plastic but subsequent growth was highest with hairy vetch. Superior vigor with hairy vetch was probably the result of higher nitrogen concentration of vetch residue relative to the other cover crops.
TILLAGE, COVER AND ALLELOPATHIC EFFECTS ON BROCCOLI.
Authors: Kelley W.T. , Coffey D.L.
Published: April 2024

`Packman' hybrid broccoli was grown under three tillage systems at three locations in 1989 and 1990 to study the feasibility of no-till production. Tillage systems consisted of 1) conventional tillage with no winter cover, 2) conventional tillage with wheat winter cover, and 3) no-till transplanted directly into paraquat killed wheat cover. Locations were at Knoxville, Greeneville and Crossville, TN. Yield, value and marketability of broccoli was significantly reduced in no-till vs conventional tillages. The possibility that small grain cover crops have a deleterious effect on broccoli growth was then investigated. Broccoli was grown in greenhouse pots with solutions of ferulic, syringic, p-coumaric, p-hydroxybenzoic and vanillic acids at 1, 10, 100 and 1000 μM concentrations and compared to controls which received only water. Shoot dry weight and plant height were both reduced with increasing acid concentrations. Soil samples were taken from field plots in 1990 and analyzed for levels of these acids using HPLC. Soils with higher levels of mulch had higher levels of ferulic and p-coumaric acid, but similar levels of the other acids. Allelopathic effects of the cover crop is a potential cause of reduced broccoli yields under no-till conditions.
706 (PS 6) THE INTERACTIVE EFFECTS OF SHIITAKE MUSHROOM STRAINS AND WOOD SPECIES ON THE YIELD OF SHIITAKE MUSHROOMS
Authors: Sabota Catherine M.
Published: April 2024

Shiitake mushrooms are grown on hardwood logs or bagged synthetic hardwood media. Domestic production of shiitake mushrooms was 3.9 million pounds in 1990-91 with a value of $16.3 million. Production of shiitake is expanding throughout the U.S., but shiitake mushroom strains are so environmentally sensitive, and wood species so diverse that evaluations of shiitake strains and wood species must be conducted on a regional basis to provide reliable results for producers. The objectives of this project were to determine the best wood species, the most productive shiitake strain and the species/strain interaction for the southern region. At the end of 30 months, there were very significant (P<0.01) differences among strains and wood species and a significant (P<0.05) interaction. Five wood species--sassafras, white oak, red oak, sycamore, and cherry--were each inoculated with 8 shiitake spawn strains–WR46, V3, WW44, West Wind, Twice Flowering, WW70, CW25, and WR85. Logs were soaked as needed and mushrooms were harvested at marketable sizes. The shiitake strains WR46, WW44, and WW70 produced the highest yields over all wood species and red oak and white oak were the most productive tree species over all shiitake strains. The optimal shiitake strain × wood species combinations were WW44 and WR46 on red oak and WW70 on white oak.
710 (PS 6) NITROGEN EFFECTS ON PAPRIKA PEPPER FOR MECHANICAL HARVEST
Authors: Maness Nancy E. , Motes James E.
Published: April 2024

Nitrogen rates were evaluated on paprika (Capsicum annuum L.) grown at uniform populations over three years. The objective was to evaluate the influence of N rate on plant lodging and fruit yield and quality in production for mechanical harvest. Three rates of N were evaluated; 45, 90, and 135 kg ha-1. Yield of marketable red and non-red pods increased with the higher rates of N. Plants were taller and stem weight was greater with the higher rates of N. Plant lodging was not significantly influenced by N rate. Plant uprooting force was greater as the N rates increased. Red color was lower with the higher N rates. Percent of the total fruit yield that was red did not differ due to N rate. The disadvantage to higher N rates, in addition to cost, was less red color in the marketable fruits. The higher rates of N would allow more successful mechanical harvesting of paprika due to improved plant anchorage.
DETERMINATION OF OPTIMAL SPAN FOR PLANTING AMARANTH IN MIDDLE GEORGIA
Authors: Singh Bharat P. , Whitehead Wayne F.
Published: April 2024

Amaranth, Amaranthus spp., is a promising summer leafy vegetable for the Southern United States. Planting of greens is usually spread over a period of time to enable growers to supply the market on a continuous basis. This study was carried out to establish the time span for planting amaranth in Middle Georgia. A. tricolor, genotype “RRC 241” was planted in a randomized complete block experiment on six planting dates one month apart between 14 April and 14 September. Data on plant height, photosynthetic rate and green fresh weight were collected 40 days after planting. June, July and August plantings had similar plant height, which was significantly greater than other planting dates. The plants from June seeding had the highest photosynthetic rate of 25.2 μmol m-2 s-1. Green yields from April, May, June, July, August and September plantings were 0, 0.1, 9.1, 7.4, 5.7 and 2.5 Mg ha-1, respectively. It was inferred that June and July were the best months for planting amaranth in Middle Georgia.
EFFECT OF SHADING ON TOMATO
Authors: Russo V. M.
Published: April 2024

High day and/or night temperatures interfere with fruit set of tomato (Lycopersicon esculentum Mill.). Shading may protect flowers and increase fruit set and yield. The cvs. `Flash' and `Sunny', which do not set fruit under night temperatures above 21.1°C were planted in mid-May, mid-June, and mid-July in 1991 and 1992 into a Bernow fine-loamy, siliceous, thermic Glossic Paleudalf soil at Lane, Oklahoma. Sixty-percent shade cloth was attached to T-shaped supports over one-half of the plots three weeks after planting. High-low temperature thermometers were suspended on supports in beds with and without shade. Shading reduced high and low temperatures by 2.5 and 1°C below ambient. Earlier planting improved yield, but cultivar or shading did not. Shading increased plant dry weight in 1992. Dry weight was positively correlated (p=0.01) with yield. Shading did not increase yield. Other levels of shading, removal of shade for a portion of the day, or erecting shading at transplanting may affect yield differently.
RYEGRASS AND CLOVER AS LIVING MULCHES FOR SWEET CORN ON SANDY SOIL
Authors: Newenhouse Astrid C. , Harrison Helen C.
Published: April 2024

Two living mulches were studied for their effect on weed control and nitrogen cycling in sweet corn grown on sandy soil under sprinkler irrigation. Plots with either annual ryegrass (Lolium perenne) or dwarf white clover (Trifolium repens) planted between sweet corn rows were compared to plots kept weed free by cultivation or herbicides. Each sweet corn plot (18.3m × 3.7m) was split into two subplots according to level of applied nitrogen. One subplot received 112 kg N/ha (100 #/A) and the other 224 kg N/ha (200#/A). Nitrate and ammonium levels were measured in soil samples and nitrogen levels were measured in plant tissue samples. Measurements such as corn height were taken, as well as percent mulch cover, plant tissue fresh weight and dry weight, total corn yield and marketable yield, and weed counts. Applied nitrogen leached through the soil profile more rapidly than expected (within 2 weeks) and sweet corn growth and yield were poor in all the low level nitrogen plots. Even at the high nitrogen level, sweet corn yield was limited by mulch growth. The weed control benefits of this living mulch system could potentially be realized if mulch competition were limited, especially during early growth stages of the corn.
GROWING GLOBE ARTICHOKES AS AN ANNUAL IN VIRGINIA
Authors: Welbaum Gregory E.
Published: April 2024

The globe artichoke (Cynara scolymus L.) is a herbaceous, perennial dicot grown for its immature flower bud. Globe artichokes are usually propagated vegetatively from root divisions or offshoots, because plants grown from seed lack uniformity. Furthermore, only a small percentage of plants grown from seed flower during the first season without vernalization. The globe artichoke is not winter hardy and cannot be grown in areas where temperatures are <-10°C without protection. The cultivar Imperial Star was developed in California to produce uniform plants from seed and a high percentage of buds the first year. In this study, Imperial Star (IS) and Green Globe (GG) were evaluated for their ability to produce a crop during the first season from seed without vernalization in Virginia. Eight-week-old transplants were set in the field on 14 May 1991. The harvest period began on 12 August for both cultivars and ended on 28 September and 8 November for GG and IS, respectively. Eighty-one percent of the IS produced buds compared to 25% for GG. The average bud yield per plant was 12 for IS and 9 for GG. Ten and 9% of the buds were rated as off-type for IS and GG, respectively. The average bud weight was 77 and 80 grams for IS and GG, respectively. Only 54 and 49% of the IS and GG buds, respectively, exceeded the marketable weight of 75 grams. The percent marketable yield for IS was 46% and 42% for GG. The estimated marketable yield per hectare was 54,600 and 4,800 buds for IS and GG, respectively. Imperial Star is a significant improvement over GG plants grown from seed in short season areas.
MORPHOLOGICAL EFFECTS OF VARIABLE LEVELS OF ROOT RESTRICTION ON `LORING' AND `REDHAVEN' PEACHES IN DIFFERENT ENVIRONMENTS
Authors: Alvarez Leonardo R. , Beyl Caula
Published: April 2024

A greenhouse and parallel field study were established to evaluate different levels of root restriction and their influence on shoot development. One year old `Loring' and `Redhaven' peach (Prunus persica L. Batsch) were grown for 7 months in containers with volumes ranging from 1.93 to 19.2 L using a mixture of kitty litter, sand (1:1v). Plants were irrigated daily and fertilized weekly. Plants grown in small containers (highly restricted 1.93-3.85 liters) exhibited less leaf expansion and caliper development. Number of primary shoots, total combined length of secondary shoots, and total length of all shoots were reduced. Shoot/root ratio was not altered by the container volumes suggesting a coordination of root and shoot growth modulated by the container volume. The same trends were observed in both field and greenhouse. Root fresh weight was reduced by the highly restricted versus the less restricted treatment (15.4-19.25L) the same extent irrespective of cultivar and location with values ranging from 33.1-38.6%.
735 (PS 7) COMPARATIVE GROWTH AND PHYSIOLOGY OF RED- VERSUS GREEN-FRUITED STRAINS OF SELECTED EUROPEAN PEAR CULTIVARS
Authors: Martin Mario M , Larsen Fenton E , Higgins Stewart S , Andrews Preston K , Ku Maurice
Published: April 2024

Several growth and gas exchange parameters were measured on potted, 1-year-old greenhouse grown trees of the green-fruited cultivars, `Bartlett', `d'Anjou' and `Clappe's Favorite' and their red-fruited sports, `Red Bartlett', `Red d'Anjou' and `Kalle'. Trees were on seedling `Bartlett' rootstock. In addition to growth and gas exchange, total chlorophyll and soluble protein content and RubisCo activity were assayed. Green-fruited cultivars required less leaf area to support a unit of biomass than did red-fruited cultivars. `Clappe's Favorite' had higher maximum CO2 uptake than `Kalle', although there were no CO2 uptake differences between green- and red-fruited `Bartlett' and `d'Anjou'. Dark respiration was less negative in `Bartlett' than `Red Bartlett' and lower in `d'Anjou' than `Red d'Anjou'. There were no differences in quantum requirements for photosynthesis between green- and red-fruited cultivars. These observations may elucidate reasons for inferior growth in red-fruited sports compared to their parents.
EFFECTS OF FIVE DWARFING ROOTSTOCKS ON GROWTH, PRECOCITY AND LEAF MINERAL COMPOSITION OF APPLE CULTIVARS
Authors: Khan Shakeel A. , Matta Frank B.
Published: April 2024

The influence of MM-111, MM-106, M-7A, M-26, and Mark rootstocks on growth, precocity and leaf mineral composition of various apple cultivars (Royal Gala, Ultra Mac, Empire, Jon-A-Red, Ultra Gold, Blushing Golden and Braeburn) were evaluated for two years in Mississippi. The smallest trees were observed in case of `Ultra Mac' and `Blushing Golden' on M-7A rootstock in 1991. Mark in the second year for all combinations produced the smallest trunk cross-sectional area (TCSA) as compared to all other scion stock combinations. All rootstocks induced precocity in `Royal Gala', `Jon-A-Red', `Ultra Gold', `Braeburn' and `Blushing Golden'. `Ultra Mac' and `Empire' remained vegetative with the only exception of `Empire' on Mark which showed precociousness. Rootstocks had a significant effect on nutrient contents of N, in leaves of `Ultra Mac', `Empire', `Ultra Gold' and `Blushing Golden'; on Mg in leaves of `Royal Gala', `Jon-A-Red', `Ultra Gold' and `Blushing Golden'; on Cu in leaves of `Empire', `Ultra Gold' and `Blushing Golden'; on Mn in leaves of `Empire' and `Ultra Gold'; on Ca in leaves of `Jon-A-Red' and `Ultra Mac'; on K in leaves of `Braeburn'; on Zn in leaves of `Ultra Mac'; and on Fe in leaves of `Empire'.
THIRD YEAR YIELD OF A HIGH DENSITY APPLE ORCHARD AS INFLUENCED BY TRAINING SYSTEM, IRRIGATION AND SOIL TREATMENT IN A REPLANTED, OLD ORCHARD SITE.
Authors: Unrath C.R.
Published: April 2024

In April, 1990, `Smoothee Golden Delicious' trees on Mark rootstock were planted in a high density orchard, 1.5m × 3.0m = 2152 trees/ha (5′×10′ = 871 t/a), in an old apple orchard site. Soil treatments of preplant fumigation (F) with methylbromide, fumigation plus postplant Ridomil (F+R) in spring and fall and monoammonium phosphate (MAP) incorporated into the tree hole were included to evaluate their influence on tree vigor. In 1992, slender spindle (SS) training increased third season yield by +79% over HYTEC training; supplemental summer irrigation (Irr.) +4%, F +6%, F+R +20 and MAP -17% over no soil treatment.

The HYTEC trained trees with no irrigation or soil treatment might roughly compare to a “check” or a typical grower technique, this treatment yielded 13,364 kg/ha (284 bu/a). Looking at some other selected treatments; SS w/no irr. or soil trt. increased yield by +27% over the HYTEC (check) trt.; SS+F = +63%, SS+Irr. = +107%, SS+Irr.+F = +112% and SS+Irr.+ F+R = +169% or 35,902 kg/ha (763 bu/a).
CITRUS COLD PROTECTION WITH SPRINKLERS
Authors: Martsolf J. David
Published: April 2024

Observing plant damage following a frost or freeze is perhaps the oldest and likely one of the most frequently used methods by horticulturists to assess relative merits of protection methods. To facilitate that method, a citrus orchard of 66 Ambersweet on Sour Orange, 198 Orlando Tangelo and 197 Robinson tangerine, the latter two varieties on Carrizo Citrange, was planted in early April of 1990, on the main campus of UF. The variety rows run the N-S with trees separated by 4.6m. The 11 different sprinkling treatments run E-W with separations of 6.1m. When 461 sprinklers are utilized the well delivers rates up to 60 l/hr/nozzle. A visitor can walk a N_S middle and view each treatment on a particular variety in series. During the winter of 90-91, half the trees had conventional under-tree sprinklers while the other half had various types of in-tree sprinklers. Following an advective freeze, Feb. 15-17, 32% of the trees with in-tree sprinklers had broken limbs compared with 4% of those with under-tree sprinklers. But estimates of canopy damage indicated less difference between the treatments, and measurements of tree height before and after freezes were so variable that significant differences were not apparent. Observations following mild freezes in 91-92 indicated high variability in the effects of a particular method on individual trees. Problems in the development of a tree imaging technique using a still image video camera [Cannon RC-250] and the use of such observations in refining mechanismal models are highlighted.
A HYPERTEXT INFORMATION SYSTEM FOR CROP LOGGING OF MACADAMIA (MACADAMIA INTEGRIFOLIA)
Authors: Kobayashi Kent D. , Hirae Howard H. , Bittenbender H.C.
Published: April 2024

Crop logging is a useful tool to keep track of the nutrient status of fruit trees. Crop logging can help extension personnel and farmers diagnose possible nutrient deficiency or toxicity problems and schedule fertilizer practices. A hypertext information system called “Tissue Analysis” was developed for crop logging of macadamia (Macadamia integrifolia Maiden and Betch) trees. The system runs on an Apple® Macintosh® computer using the software HyperCard® 2.0. It allows the user to keep track of the tissue analyses records of different farmers and their orchards and serves as a “front end” to link to the user's spreadsheet worksheets and charts of different nutrients. The user can create and maintain a list of farmers whereby a separate file is created for each farmer that then allows the user to create and maintain a list of the farmer's orchards. For each orchard, the user can name buttons according to different nutrients and set up linkages to spreadsheet worksheets and charts to view tissue analyses records. This information system can aid extension agents and farmers in monitoring the nutrient status of different orchards, diagnose possible nutritional problems, and schedule fertilizer applications.
SUNLIGHT ATTENUATION AND NUTRITIONAL REQUIREMENTS FOR COCOA PLANTATIONS
Authors: Delgado-Nuñez Victor H. , Saavedra J. Angel
Published: April 2024

Two levels of natural sunlight attenuation and three levels of fertilizer were evaluated on five-year-old cocoa trees growing under field conditions. Sunlight effect was evaluated by comparing two densities of shade trees, Gliricidia sepium: 4×4 m and 8×4 m, allowing aproximately 25% and 50% of full sunlight (2000 μmol-2 s-1), respectively. The amount of soil-applied, fertilizer was 0 (control), 700, and 1000 g tree-1 year-1 17-17-17 (N-P-K) applied twice a year. Treatments were replicated 3 times in a split-plot design.Shade density of 8×4 m yielded the best dry cocoa bean production per ha. Production increased proportionally with the amount of fertilizer. We conclude that as the amount of light reaching tree canopy increases, the need for fertilizer also increases, and consequently yields improve. However, cocoa growers have to manage this characteristic carefully because tree life is diminished under more sunlight.
VARIATION IN AIR CAPACITY AND SATURATED FLOW IN SUBSTRATES WITH INCREASING AGGREGATE ADDITIONS
Authors: Holcomb E. J. , Drzal M.S. , Fonteno W.C.
Published: April 2024

Little research has been done on water transport in substrates. Research has concentrated on capacity factors such as porosity, air space and container capacity. The objective of this research was to measure both capacity and water transport in peat:vermiculite mixes amended with perlite and rockwool. A device was constructed to measure saturated hydraulic conductivity (Ksat) of porous substrates using a constant head system with small hydraulic gradients. When 50% peat: 50% vermiculite (v/v) was blended dry and brought to specific mass wetness (MW), perlite substitutions (for vermiculite) of 5, 10, & 20% increased aeration from 5.8 to 9.3%. Ksat showed a corresponding increase from 6.49 to 12.18 cm/min. When the peat and vermiculite components were moistened before blending (MW = 3.5 and 1.5, respectively), the same additions of perlite did not produce incremental changes in aeration. However, Ksat was markedly increased from 18 to 28.6 cm/min. Water-repellant (WR) rockwool increased aeration only at the 20% addition when mixed dry, but increased aeration significantly at lower rates when blended wet. Ksat was not influenced by WR rockwool additions, but was higher in formulations blended wet.
FERTILIZATION AND IRRIGATION AFFECT HOLLY GROWTH
Authors: Yeager Thomas H.
Published: April 2024

Multiple branched liners of Ilex vomitoria were greenhouse-grown in 3-liter containers with a common nursery medium. Each plant was fertilized with 2.5 g N surface-applied as Osmocote (18N-2.6P-10K) and irrigated with 460 ml water twice a week or fertilized with a total of 0.5, 1.0, 1.5, or 2.5 g N from a nutrient solution (6N-1P-3K) and irrigated with 460 ml water twice a week or evapotranspiration (ET) plus 10%, 30%, or 50%. Nutrient solution treatments were divided equally among 26 weekly applications. Shoot dry weights (22 and 25 or 26 and 25 g, respectively) for plants irrigated with ET plus 30% or 50% and receiving 1.5 g or 2.5 g of N were not different and these treatments had larger shoot dry weights (13 and 14 g, respectively) than plants fertilized with 0.5 g of N. Shoot dry weights were similar for plants irrigated with 460 ml water twice a week and fertilized with 2.5 g of N from the nutrient solution or Osmocote. Shoot dry weights of plants irrigated with ET plus 30% or 50% were similar to plants irrigated with 460 ml water twice a week when plants received 1.0, 1.5, or 2.5 g of N.