bluuebunny/crossref_metadata_2025 huggingface dataset:
NURSERY STOLON SERIES AND ROOTING DATE, AND SUBSEQUENT PLANT GROWTH AND DEVELOPMENT IN TWO STRAWBERRY CULTIVARS
Authors: Larson Kirk D.
Published: April 2024

Variations in plant vigor and productivity are often observed in annual strawberry plantings, despite the use of single-source clonal plant material. To determine the influence of stolon series and stolon rooting (set) date in the nursery on subsequent plant growth, developing stolons of two cultivars (`Chandler' and `Selva') were tagged and set in a nursery (1013 m elevation, 41.2 N latitude) at 3-wk intervals beginning in mid-June, 1992. On 30 Sept, 1992, for each cultivar, stolons were dug and placed in one of five groups: 1) 1st and 2nd series stolons set on or before 1 July; 2) 1st and 2nd series stolons set on 21 July; 3) 3rd and 4th series stolons set on 21 July; 4) lst and 2nd series stolons set on 14 August; and 5) 3rd and 4th series stolons set on 14 August. For each stolon group and cultivar, six plants were randomly selected for determinations of fresh wt and crown diameter, then planted in 2-L containers in growth chambers (11 hour daily photoperiod, 750μmol m-2 s-1, 17/11 C). Leaf number and canopy diameter were determined at 2-wk intervals for 10 wks, after which plants were harvested for determinations of root and shoot dry wt, and leaf area. Cultivar differences were observed, but relative group rankings for most variables were fairly consistent between cultivars. For both cultivars, group 1 had the greatest, and groups 4 and 5 had the smallest initial crown diameters and stolon fresh wts. However, groups 1 and 4 had greatest final leaf area, shoot dry wts, and crown and leaf numbers, suggesting that stolon series can influence plant growth and development in strawberry.
LOW INPUT PEACH PRODUCTION: FIRST-YEAR RESULTS
Authors: Hubbard Mark A. , Flore J.A. , Hansen E. , Shane W. , Johnson J. , Wise J. , Whalon M. , Bird G. , Jones A.
Published: April 2024

Three systems of peach production have been established (Flore, et al., 1991, HortScience 26(6):747) utilizing three levels of chemical input: conventional input, moderate level, and low level. The moderate and low levels of chemical input use increasing degrees of IPM. In 1992, data were collected on yield, insect and disease impact on fruit quality, vegetative growth, nitrate and simazine levels in the soil, and insecticide residues in the fruit. The yield per tree was substantially higher in the conventional treatment but this effect could be attributed to an early spring frost, local topography, or the treatment system. The percentage of fruit free from insect and disease damage was highest in the conventional treatment (95.1%), but the low input had a relatively high percentage of fruit free of damage (79.6%). Shoot cold hardiness of one year old shoots was not affected by treatment. Bud survival after a spring frost was greater in the conventional orchards, but topography may have influenced this parameter. Nitrate levels 2 m in the soil and sim-azine residues in the A horizon were not affected by treatment. Lorsban®, Guthion®, and Asana® residues in fruit are currently being analyzed and will be discussed. Additional data collected in 1993 and future years will contribute more information on the use of the low and moderate chemical input treatments on peach production.
N AND P APPLICATION METHODS AND TIMING EFFECTS ON APPLE ESTABLISHMENT: FERTIGATION VS TOP-DRESSING
Authors: Kupperman Ken , Rom Curt R.
Published: April 2024

Six fertilizer regimes applied to newly planted `Smoothee Golden Delicious' and `Jonee' on M.26 EMLA were evaluated during two years of establishment. Treatments were: 1) control (no fertilizer applied), 2) spring top-dress (granular), 3) fall top-dress (granular), 4) split top-dress (granular) spring 50%/fall 50%, 5) spring fertigation, and 6) fall furtigation. All fertilizer treatments received 10g P/tree each season with triple super phosphate used for top-dress form and ammonium polyphosphate with fertigation. Ammonium nitrate was the N source for all treatments applied at a rate of 50g N/tree/year of tree age and adjusted accordingly for trees fertigated with APP. In the second year, `Jonee'-control trees had significantly more bloom than other treatments; with `Smoothee'-spring fertigated trees having more bloom than other treatments. Set, in second year however, was greater for both cultivars with spring fertigation. Trunk cross sectional area of both cultivars at the end of two seasons was significantly smaller under spring fertigation. Both fertigation treatments significantly decreased soil pH over two seasons with an associated increase in foliar Mn occurring.
ROOTSTOCK EFFECTS ON NORTHERN SPY APPLE LEAF COMPOSITION
Authors: Stiles Warren C. , Cummins James N.
Published: April 2024

Leaf samples collected during the 1988-90 seasons were analyzed to evaluate influence of selected rootstock clones on the composition of Northern Spy apple leaves. Rootstocks included 17 elite selections from the Geneva breeding program plus M.9, M.26, M.7, MM.106 and MM.111 as references. Rootstock selections were grouped according to relative vigor and compared with appropriate references. Significant rootstock effects were more frequent in the two smaller tree-size groups. Each of the 10 elements analyzed exhibited significant rootstock effects in two or more vigor groups. No rootstock selection consistently resulted in higher or lower concentrations of all elements when compared with the reference rootstock of similar vigor.
TRAINING AND ROOTSTOCK STUDIES WITH PEAR CULTIVARS ON QUINCE SIZE-CONTROLLING CLONES.
Authors: Tehrani G. , Lay W.
Published: April 2024

In 1987, a study consisting of 3 training systems (TS) [Supported modified leader (S), Free Palmette (P) and Mini-Tatura (MT)] with Anjou (A), Bartlett (B) and Flemish Beauty (FB) on Quince A & C and Provonce C134, in a high and ultradensity planting, was initiated on a fine sandy loam soil. Blossoms were counted and removed during 1988 to 1990 seasons. Palmette TS increased bloom efficiency (BE) but did not affect the number of florets/cluster. Quince C produced higher BE than either QA or C134. Bartlett had the highest BE followed by A & FB. Anjou exhibited more florets/cluster than either B or FB. Rootstock or TS did not influence this variable.

Irrespective of rootstock and training, the largest trees were FB followed by A & B. Quince C produced trees smaller than QA & C134. Mini-Tatura reduced tree size significantly compared to S & P. The cumulative yield for 1991 & 92 (5th and 6th leaves) was 85 tonnes/ha for MT compared to 35 & 37 for S and P respectively. Quince clones had no effect on yield, but A was significantly less productive than B or FB. Cultivar, rootstock or training did not affect mean fruit weight during 1992. Bartlett had higher number of pears/tree compared to A & FB. Palmette training system produced more pears per tree in comparison to S and MT.
SELECTION FOR RESISTANCE TO SWEETPOTATO WEEVIL
Authors: Thompson Paul G. , Schneider John C. , Graves Boyett
Published: April 2024

Narrow-sense heritability and selection response estimates for weevil resistance were higher based on half-sib family means than on individual plants. Resistance levels in available sources are low and evaluation with low weevil numbers is essential for differentiation. Consequently, highest performing families produce multiple plants with no injured roots and separation of resistance levels among those plants is impossible Since a large amount of additive variance is contained among plants within families and early reduction of plant numbers would increase breeding efficiency, a study was conducted to determine the effectiveness of individual plant selection in combination with half-sib families. Two plants were selected from each of the 10 highest families based on weevil resistance and yield. Selected clones were compareds for resistance levels to means of their families when tested over 2 years. Fifty percent of selected clones had higher resistance levels than their family means indicating that individual plant selection was effective. Optimum methods of combining family and individual plant selection will be discussed.
POTATO PRODUCTION IN NASA'S BIOMASS PRODUCTION CHAMBER WITH REFERENCE TO ATMOSPHERIC VOLATILES
Authors: Wheeler R.M. , Peterson B.V. , Mackowiak C.L. , Stutte G.W.
Published: April 2024

Potatoes (Solanum tuberosum cv. Norland) were grown for 105 days in a large (20 m2), closed chamber to assess their potential for life support in space. Cultural conditions included a recirculating NFT culture, 12/12 photoperiod, 16°C, 1000 μmol mol-1 CO2, and approximately 900 μmol m-2 s-1 PPF from HPS lamps. The chamber was separated into two halves with one atmosphere continuously passed through charcoal filters, while the other was not filtered. Plants grown in the filtered air showed a more “induced” appearance early in growth in comparison to plants in the unfiltered air (i.e. reduced shoot growth and early tuber bulking). Ethylene levels in the atmospheres ranged from 10 to 60 ppb in the unfiltered treatment and 10 to 40 ppb in the filtered. Mass spectral analyses indicate that the filters efficiently reduced heavier organic volatiles, but were not effective for lighter volatiles (e.g. ethylene). Biogenic emissions from the plants were identified, as well as components from glues and caulking compounds. Final tuber yields were similar but shoot biomass was higher and harvest index lower in the unfiltered treatment: charcoal filtered--10.1 kg m-2 tuber FW, 1.9 kg m-2 tuber DW, 2.5 kg m-2 total plant DW, 76% harvest index; unfiltered--10.9 kg m-2 tuber FW, 1.9 kg m-2 tuber DW, 3.1 kg m-2 total plant DW, and 61% harvest index.
USE OF CONTINUOUS LIGHTING DURING THE RICE LIFE CYCLE TO INCREASE GRAIN YIELD FOR A CELSS
Authors: Volk Gayle M. , Mitchell Cary A.
Published: April 2024

Rice has been selected as a CELSS candidate species for human life support in space. Research optimizing environmental parameters, such as daylength, has increased overall grain yield. Rice is a short day plant, but after floral induction, it can be switched to continuous light. Greenhouse studies of Ai-nan-tsao, a high tillering japonica cultivar, have shown that edible yield rates can be increased from 6.2 g m-2 d-1 to 14.1 g m-2 d-1 if the cultivar is switched from 8-h days to continuous light after panicle emergence. If calculated on a volume basis, those yields are 8.3 g m-3 d-1 and 20.2 g m-3 d-1, respectively. Shoot harvest index was 37% for plants grown under 8 h days, but increased to 55% for plants switched to continuous light There was a corresponding increase in non-edible biomass accumulation by the plants. Also, individual panicle weight increased from 0.54 g to 1.12 g when plants were switched to continuous light Studies are in progress with 8-h days applied for 1 or 2 weeks during a continuously illuminated vegetative growth period. This project was supported in part by NASA grant NAGW2329.
DEMONSTRATING INDIRECT AND DIRECT SHOOT ORGANOGENESIS USING INTERNODES OF MYRIOPHYLLUM AQUATICUM
Authors: Kane Michael E. , Philman Nancy L.
Published: April 2024

There are few plants from which suitable explants can be obtained to reliably demonstrate rapid shoot organogenesis in vitro. A laboratory exercise has been developed using internodes of Myriophyllum aquaticum, an amphibious water garden plant. Stock shoot cultures are established and maintained in vitro from nodal explants cultured on agar-solidified medium consisting of half-strength Murashige & Skoog salts (MS) and 3% sucrose. Students use these cultures as the source of internode explants. Explants are cultured on agar-solidified full-strength MS with 3% sucrose, 100 mg/liter myo-inositol, and 0.4 mg/liter thiamine-HCL and factorial combinations of 0 - 10 μM 2-isopentenyladenine (2iP) and 0 - 1.0 μM α-naphthaleneacetic acid (NAA). Adventitious shoot development occurs directly from the epidermis within 4 days and is promoted in media supplemented with 2iP alone. Cytokinin supplemented media amended with NAA induce organogenetic callus formation but reduce 2iP promotion of direct shoot organogenesis. At week four direct and indirect shoot organogenesis on the various media are enumerated and statistically analyzed.
ADVANCES IN CITRUS ROOTSTOCKS
Authors: Ferguson James J.
Published: April 2024

Citrus rootstock improvement has relied historically on clonal selections chosen from traditional field trials and from cold-hardy scion improvement programs. Although the impact of traditional plant breeding programs on citrus rootstock improvement has been limited because of biological impediments and lack of understanding of citrus genetics, newly developed techniques on the cellular and molecular level have provided new opportunities for progress.

Although trends in citrus rootstocks can be monitored through Budwood Registration data, official statistics are generally not available on rootstocks in bearing groves. Traditional screening programs include initial testing for resistance to fungal and viral diseases, nematode susceptibility, and nursery performance followed by evaluation as a budded tree. Rootstock trials underway include hybrids of `Ruby' orange/trifoliate orange, sweet orange/trifoliate orange, pummelo/trifoliate orange, and `Changsha' mandarin/trifoliate orange.
Measuring the Environmental Impact of Pesticides
Authors: Kovach Joseph
Published: April 2024

Traditionally, pesticides used to control insects, weeds and diseases are selected primarily based on their efficacy and/or cost rather than on potential environmental impact. In order to estimate the environmental impact of pesticides used in commercial agriculture, a model was developed called the Environmental Impact Quotient (EIQ). Over 120 pesticides were evaluated using 13 different toxicological criteria (leaching potential, residue potential, carcinogenicity, effect on beneficials, etc.). The EIQ values obtained from these calculations can be used to determine which pesticide is the least toxic choice or which pest management program is likely to have the lowest total environmental impact.
LOCALIZATION OF PEROXIDIZED LIPIDS IN DETERIOSOMES
Authors: Thompson J.E. , Yao K.
Published: April 2024

Fluorescent peroxidized lipids are present in lipid extracts of microsomal membranes and cytosol from young and senescing bean (Phaseolus vulgaris) cotyledon tissue. For young tissue, the peroxidized membrane lipids are mainly phospholipids, whereas those in the cytosol are primarily free fatty acids. With advancing senescence, microsomal peroxidized lipids increase by 200% relative to membrane protein and by 50% on a per cotyledon basis, and the increase is mainly attributable to enhanced levels of peroxidized free acids. Cytosolic peroxidized lipids expressed on a per cotyledon basis decline by 55% over the same period. Fractionation of the cytosol revealed that, for both young and senescing tissue, ∼50% of the cytosolic fluorescent peroxidized lipids are associated with deteriosomes, which are nonsedimentable microvesicles formed from membranes and enriched in phospholipid catabolites. Moreover, the decline in cytosolic peroxidized lipids with advancing senescence correlates with progressive impairment of deteriosome formation. Deteriosomes also contain high levels of polyunsaturated free fatty acids and exhibit strong lipoxygenase activity.
GENETIC MARKERS AND PLANT GENETIC RESOURCE MANAGEMENT
Authors: Bretting Peter K. , Widrlechner Mark P.
Published: April 2024

When suitably deployed, genetic markers facilitate all phases of plant genetic resource management, from acquisition through enhancement. This paper will review the kinds of plant genetic resources and genetic markers, analytical methods for marker data, and specific applications of genetic markers to plant genetic resource management, such as (i) assessing a collection's “gaps” and redundancy; sampling strategies; characterizing newly acquired germplasm; maintaining “trueness to type”; monitoring genetic shifts; monitoring germplasm viability and health; developing optimal utilization strategies from genetic marker data; exploiting associations among horticulturally meritorious traits and genetic markers. Finally, general conclusions and forecasts regarding future prospects for applying genetic markers to these tasks will be presented.
THE INFLUENCE OF ROTATION AND COVER CROP MANAGEMENT ON THE PRODUCTION OF FRESH-MARKET VEGETABLES.
Authors: Mwaja Vasey N. , Masiunas John B.
Published: April 2024

The purpose of this study was to determine the effect of rotation and cover crop management on vegetable production. Winter rye (Secale cereale L. cv. Wheeler) and hairy vetch (Vicia villosa Roth.) were interseeded in the fall. The following spring, tomato, snapbean and cabbage were planted using reduced tillage methods (RT). The RT were to plant into a cover crop desiccated either with glyphosate or by mowing and disking, leaving cover crop residue on the soil surface. A preplant incorporated application of trifluralin was included as the control. The experiment was a split plot with four replications. In 1991, snapbean yields were affected by cover crop management; total yields of cabbage and tomato were not affected. Tomatoes ripened significantly earlier in no-till systems. However, in 1992, the greatest yields were in the conventional production system. Insect infestation of cabbage was greater on bare ground and cover crop disked plots.
LEAF AND FRUIT DEVELOPMENT OF `EMPIRE' APPLE TREES AS INFLUENCED BY SHADING AND FOLIAR MICRONUTRIENTS.
Authors: Robinson Terence L. , Ren Zhongbo
Published: April 2024

Lower scaffold branches of `Empire'/M.7 apple trees which were planted in 1975 and trained as Central Leaders were shaded or left exposed from 1986-1988. Foliar micronutrient sprays of N, Zn and B were applied 3 times in the early season of each year to both shaded and exposed scaffold branches in an attempt to improve spur vigor. In 1988 spur and bourse shoot leaf area development and fruit growth were monitored. Shading resulted in greater initial spur leaf area at 3 weeks after bloom but shorter leaf duration. Spurs on shaded branches had lost 2/3 of their leaf area by 11 weeks after full bloom while exposed branches had lost only 25%. Bourse shoot leaf area was greater on exposed branches throughout the season. Foliar sprays of micronutrients did not increase leaf area or leaf duration of either spur leaves or bourse shoot leaves. Fruit growth rate was reduced by shading most in the early season. Final fruit size, color, soluble solids and dry matter were reduced by shading. Foliar micronutrient sprays did not affect fruit growth rate any time during the season or final fruit size, color, soluble solids and dry matter. There was also no interaction of shading and foliar nutrition on fruit size or quality. It appears that the negative effects of shading on spur vigor and fruit quality cannot be reversed by foliar micronutrient sprays.
EARLY FALL COLD HARDINESS AND NONSTRUCTRAL CARBOHYDRATE LEVELS IN YOUNG, DROUGHT-STRESSED APPLE AND CRABAPPLE ON DIFFERENT ROOTSTOCKS
Authors: Longstroth Mark A. , Fernandez R. Thomas , Flore James A. , Schutzki Robert T. , Perry Ronald L.
Published: April 2024

One-year-old `Imperial Gala' on Mark, M.9 EMLA, and MM.1ll; and `Indian Summer' on MM.lll and MM.106 rootstocks were planted in a rain exclusion shelter in May 1991. All trees were irrigated. Half the trees were drought stressed and received no water for two, 30-day drought cycles. Four trees from each scion ×rootstock×irrigation combination were excavated in mid-October. Nonstructural carbohydrate reserves of stems and roots were determined. Cold hardiness, determined by visual examination of tissue after controlled freezing, was influenced by rootstock, drought, and stem age. Concentrations of several carbohydrates were correlated with cold hardiness. Regression models of carbohydrate concentrations on cold hardiness were significant. Removal of root tissue, which was cold sensitive and had high carbohydrate levels, altered the regression equations. Rootstock significantly influenced root concentrations of sorbitol, sucrose, and starch. Root sorbitol increased following drought stress. Mark and MM.106 roots had the largest increases in sorbitol. Irrigated Mark roots had very low levels of sorbitol.
METHOD OF IRRIGATION AND FERTILIZER APPLICATION INFLUENCE GROWTH AND NITROGEN RECOVERY FOR `SCARLET ELITE' GERANIUM
Authors: Knight Patricia R. , Eakes D. Joseph , Gilliam Charles H.
Published: April 2024

Seed geraniums (Pelargonium × hortorum Bailey `Scarlet Elite') were grown in 10-cm pots in a 1 pine bark : 3 peat : 1 perlite (v:v) medium from 17 April until 1 June 1992. Plants were watered with conventional overhead irrigation (CI) or in ebb and flow troughs (EF) and fertilized with Peter's Geranium Special 15N-6.5P-12.5K (PGS) or Osmocote 14N-6.1P-11.6K (OS). Fertilizer application had no influence on shoot dry weight. Shoot dry weights were greatest for plants given CI. Shoot tissue N was greatest for plants given CI or PGS. Root tissue N was greatest for plants given EF with PGS, and plants watered by CI with OS. Irrigation method had no influence on N remaining in the growing medium. Medium N content was greatest for plants receiving PGS.
DETERMINING STANDARDS FOR WATER QUALITY IN CLOSED NUTRIENT SYSTEMS FOR DUTCH FLORICULTURE
Authors: Baas R. , Buwalda F. , Nijssen H. , van den Berg D.
Published: April 2024

Glasshouse experiments were carried out to determine the extent NaCl accumulation up to 30 mM decreased production and quality of chrysanthemum, gerbera and carnation. At NaCl concentrations higher than 8 mM (468 ppm), transpiration, flower and peduncle weight decreased. The effects were most pronounced during periods of high irradiation. Vase life was not influenced by NaCl. Na uptake concentration (mmol/l) was linearly related with the concentration in the nutrient solution, and was 8%, 5% and 2% of the external concentration for gerbera, chrysanthemum and carnation, respectively. Compared to Na, Cl uptake was higher and non-linearly related to the outer concentration. Apart from chloride/nitrate antagonism, no clear general interactions were found for other ions in relation to NaCl addition. The results imply that in order to avoid Na accumulation above suboptimal levels, irrigation water in closed nutrient systems should contain less than 0.6, 0.4 and 0.16 mM NaCl for gerbera, chrysanthemum and carnation, respectively.
EFFECT OF CULTIVAR AND INSECTICIDE SPRAYS ON TARNISHED PLANT BUG INJURY TO STRAWBERRIES
Authors: Handley David T. , Pollard Jamas E.
Published: April 2024

Six strawberry (Fragaria × ananassa Duch.) cultivars known to vary in susceptibility to tarnished plant bug (Lygus lineolaris P. de B.) injury (apical seediness) were grown under three insecticide regimes including no spray, one spray and three sprays, to determine if differences in susceptibility could be used to modify chemical controls for this insect. The most susceptible cultivars harbored more tarnished plant bug nymphs than the least susceptible cultivars. Differences in injury among cultivars was greatest when no insecticide was applied. `Honeoye' and `Sparkle' had the least amount of apical seediness, followed by `Redchief', `Guardian' and `Kent'. `Mic Mac' consistently had the highest level of injury. When insecticide sprays were reduced, apical seediness did not significantly increase for cultivars exhibiting low susceptibility.
EVALUATION OF LOW-INPUT PECAN ORCHARD FLOOR MANAGEMENT SYSTEMS
Authors: Rice N.R. , Smith M.W. , Eikenbary R.D. , Tedders W.L. , Wood B.W. , Taylor G.G. , Landgraf B.S. , Barlow G.E.
Published: April 2024

Legume ground covers were evaluated in pecan orchards to reduce nitrogen inputs and increase beneficial insects. Treatments were established at two sites in Oklahoma, each with 5 ha of a `Dixie' crimson clover/hairy vetch mixture and 5 ha of grass sod. Nitrogen was applied at 0-200 kg·ha-1 to the sod plots, but legume plots were not fertilized. Aphids and selected arthropods were monitored on ground covers and in the pecan canopies. Data indicated that a mixture of crimson clover/hairy vetch supplied up to 186 kg·ha-1 N to the trees. Beneficial arthropods monitored were Coccinellidae, Chrysopidae, Nabid, Syrphid, and spiders. Lady beetles, primarily Hippodamia and Coleomegilla, were the most important aphid predator in the spring, and green lacewing was the most important fall predator. There were fewer aphids infesting pecans using a crimson clover/hairy vetch ground cover than a grass sod.
CUTICULAR MEMBRANE FORMATION AND OCCURRENCE OF BUNCH ROT (BOTRYTIS CINEMA PERS.:FR.) WITH 3 VITIS VINIFERA L. CULTIVARS.
Authors: Percival David C. , Fisher K. Helen , Sullivan J. Alan
Published: April 2024

Leaf removal treatments were applied to Riesling during 1990 and 1991, and to Cabernet Franc and Optima in 1991. Clusters were sampled to examine the effect of berry exposure, berry contact, time of sampling, and cultivar on cuticular membrane formation and the occurrence of bunch rot (Botrytis cinerea Pers.:Fr.). Non-contact and contact cuticle proper and epicuticular wax berry samples were examined qualitatively using cryogenic scanning electron microscopy and quantitatively using enzymatic separation and chloroform extraction.

Exposed Riesling samples had 18.6% and 35.0% more epicuticular wax and cuticle proper respectively than shaded samples. Non-contact Riesling samples had 15.7% and 35% more epicuticular wax and cuticle proper than contact samples, and although significant, epicuticular wax and cuticle proper weights of Riesling increased by only 5.7% and 4.5% respectively, between veraison and harvest. Although exposed cuticular membrane samples from all 3 cultivars had more epicuticular wax and cuticle proper than shaded samples, large differences between cultivars were present. Clusters from the hand leaf removal (i.e. exposed) treatment of all 3 cultivars examined had significantly less bunch rot than clusters from the control (i.e. shaded). Cabernet Franc was the most tolerant end Optima the most susceptible of the 3 cultivars to bunch rot. Time of sampling and differences between years also influenced the occurrence of bunch rot for Riesling with less rot present at veraison compared to harvest and less rot present at the 1990 compared to the 1991 harvest. Exposure, cultivar and level of contact within the cluster are all important factors in the cuticular membrane formation process and contribute greatly to the overall susceptibility of a grape cultivar to bunch rot when grown in a temperate climate.
IDENTIFICATION OF GRAPFVINE FANLEAF VIRUS IN XINJIAN
Authors: Xuednan Liu , Yuqi Yin , Xinmin Cui
Published: April 2024

A isolate from vineof Vitis vinifera cv. Monukka with fanleaf-like symptoms in Vill Xinjian was obtained and studied. It infected Chenopdium quinoa, C. amaranticolor, Gomphrena globesa, Cucumis sative, Hicotana clevelandii. The virus is isometriealspherical particle of 30nm in dianeter. In the double diffusion test in agar and the indexing of immunosorbent electron microscopy(ISEM), it gave positive reaction with GFV antiserm. The virus was propagated on O. quinoa and purified by using Chloroform-Butanol + PEG(P. wt.6000), differental centrifugation and sucroses density gradient cetrifugation. The virus particle contains a protein subunit fM.wt. 56234D. and be composed of 17 species 461 acides. On the results above, the isolate was identified as Grapevine Fanleaf Virus(GFV).
WHOLE-TREE GAS EXCHANGE, MITE DAMAGE, AND FRUIT DEVELOPMENT IN APPLE.
Authors: Lakso Alan N. , Mattii Giovan Battista , Nyrop Jan P. , Denning Steven S.
Published: April 2024

This study examined the hypothesis that late-season European Red Mite (ERM) injury effects on fruit development are mediated via carbon relations of apple trees. ERM injury were allowed to develop in mature semi-dwarf `Starkrimson Delicious'/M26 trees with moderate crops (about 30 t/ha). Populations of ERM developed concurrently in all trees, but were controlled with miticides at different mite-day levels, giving a range of final mite-days from 300 to 2100 on individual trees as estimated by weekly leaf sampling for mites. At intervals through the season fruit growth was monitored. Diurnal whole tree photosynthesis was measured with eight clear flexible “balloon” whole tree chambers. Before the mite injury developed, fruit sizes were very similar, but in the last 60 days before harvest differences in fruit weights of up to about 50 grams were induced by mite injury which reduced whole tree photosynthesis comparably. The final fruit growth and size were well correlated with whole tree photosynthesis per fruit. Effects on other fruit quality factors were minor. These results suupport the hypothesis that whole tree source/sink balance may be an integrator of crop load and mite injury effects on fruit development. Fruit growth rates may be a practical monitor of the integrated effects of crop load and stresses.
ADVENTURES IN BROADCASTING: TEACHING LANDSCAPE MANAGEMENT BY SATELLITE
Authors: Rupp L. A. , Kjelgren R. , Lindsay R. E. , Johnson W. E.
Published: April 2024

The AG*SAT network is designed to allow sharing of instructional resources by broadcasting courses among peer institutions. In the fall of 1992 we taught the course “Landscape Management in the Interior West” by satellite over AG*SAT to students in Utah, Nevada, Nebraska, and Idaho, and on the Utah State University campus. Impetus for the course was to address the unique landscape needs of a region with few formal horticultural programs. The broadcast originated from an on-campus studio without students present, but with a two-way audio link. We encountered several unforeseen challenges during course preparation. It required a substantial time investment of approximately four hours for every hour of instruction. Marketing among peer institutions required a three-tiered consensus among faculty, deans of instruction, and telecommunication services. The initiative of peer faculty was very helpful in achieving this consensus. We were more successful in bringing the course to extension offices than to campuses. Student response varied with location and degree of involvement. On-campus students were critical of a perceived lack of face-to-face contact with faculty. Positive responses came from viewers in remote locations where access to college-level courses is otherwise limited. In lieu of personal interaction, videos and very detailed written support materials were critical in eliciting student involvement.
INTEGRATIVE PEST MANAGEMENT IN TEA PLANTATION
Authors: Jlcai Tan , Deng-Xing  , Zunbing Qin
Published: April 2024

Two major measures were practiced in Dongshanfeng State Farm in Hunan province of China from 1988-1992. a/ Plant trees and readjust structure of crops to protect the natural enviornment and ecosystem of the tea plantation; b/ Put chemical control under ecological blance by using agricultural technical measures as the basic way and natural control of insectpest as the leading technigues. It showed the total average of poisonous element in air SO2 0.025mg/Km3, NOx 0.009mg/Km3, Tsp 0.059mg/km3; there were no-pollution in water of irrigate the fields, the tea plantation soils and the made tea; the quanting of natural enemy intea plantation were increased It had benefited of farm greatly both in production and ecology.
EFFECT OF PINOLENE AND ABSCISIC ACID ON “BALADY” ORANGE TREES UNDER HEAT STRESS
Authors: Bacha Mohamed A. , El-Hamady Moustafa , Abo-asker Hilal M.
Published: April 2024

Foliar sprays of pinolene (0,2 and 4%) and abscisic acid (ABA) (0,50 and 100ppm)were used to reduce heat stress effect on “Balady” orange trees under the Riyadh region,Saudi Arabia for two seasons. Pinolene treatments maintained higher leaf chlorophyll content than the control. Yield was slightly increased by pinolene treatments. Fruits had high values for most physical properties due to these treatments. TSS% and TSS/acidity ratio were increaced, acidity was decreased, while vitamin C was unaffected. Abscisic acid treatments reduced leaf chlorophyll content, compared to the control, but had no effect on yield. Such treatments increased fruit diameter (at 50 ppm) and fruit weight and juice volume (at 100 ppm). ABA showed no influence on most of the chemical properties of the fruits. In view of these results, it can be stated that pinolene was more influencial in reducing heat stress effect than ABA on “Balady”orange trees.
INDUCTION OF CHILLING TOLERANCE DURING GERMINATION OF CUCUMIS SATIVA CV. POINSETT 76
Authors: Jennings Paul H. , Saltveit Mikal E.
Published: April 2024

Cucumber seeds are resistant to chilling during imbibition but become sensitive on emergence of the radicle. Since temperature shock treatments have been shown to induce stress tolerance in other species, a project was initiated to determine the effects of various shock treatments on chilling tolerance during early stages of cucumber seed germination. Heat shock, cold shock and ethanol all induced tolerance of 24 hr germinated cucumber seeds chilled at 2.5°C for 96 hr. Both time and temperature (or concentration) of the shock treatment affected the level of induced tolerance. Heat shock at 40°C for 1 hr was most effective in inducing chilling tolerance. The effects of other shock treatments will also be discussed.
DRIP IRRIGATION REQUIREMENTS FOR ESTABLISHING LANDSCAPE ORNAMENTALS
Authors: Weerts W.M. , Lownds N.K.
Published: April 2024

Five landscape species, Baccharis pilularis, Fallugia paradoxa, Juniperus sabina `Tamariscifolia', Leucophyllum frutescens, and Nerium oleander, grown in 3.8-1 containers, were planted in a loam soil and mulched with pecan shells or rock. Plants were irrigated weekly at 25, 50, 75 and 100% of estimated potential evapotranspiration (PET) determined using mean canopy cover at the beginning of the experiment. Growth was measured every two weeks and aesthetic, flowering and fruiting evaluations were made weekly. Leucophyllum and Nerium grew rapidly at a constant rate throughout the season. Baccharis and Fallugia grew rapidly in May and June and slowly thereafter. Juniperus showed a continued, moderate growth rate. In addition, there were few differences in overall plant quality, flowering or fruiting across irrigation rates. The equation for determining the irrigation of ornamentals appears to be flawed. For Leucophyllum, at the 25% rate, it predicted 980 1/plant would be required during the season while only 22 1 (2.4% of PET) was applied, producing excellent specimens.
MOLECULAR GENETIC MAPPING AND GENOME SIZE OF VITIS.
Authors: Lodhi Muhammad A. , Reisch Bruce I. , Weeden Norman F.
Published: April 2024

A project to develop a linkage map of the Vitis genome is underway using an interspecific hybrid grape population from `Cayuga White' × `Aurore'. The linkage map is based on 15 isozyme, 13 RFLP and more than 350 RAPD markers. This information is being combined with segregation data for viticulturally important traits including disease resistance to identify QTLs and mark simply inherited traits. Molecular markers, when linked with morphological traits, will find great application in map-based cloning and marker-assisted selection in grape breeding. We have also analyzed genome size of three genera of Vitacae (Ampelopsis, Parthenocissus and Vitis) and 15 Vitis species as well as 15 diploid cultivars using flow cytometry. DNA content varied from 0.84 to 1.40 pg/2C. The relative small genome size indicates that Vitis is a good candidate for molecular genome analysis. All this information will help us understand Vitis genome organization and reliability of identifying a gene linked to a marker in different populations.
EASTERN BLACK WALNUT - POTENTIAL FOR COMMERCIAL NUT-PRODUCING CULTIVARS
Authors: Reid William
Published: April 2024

Over 10,000 metric tons of eastern black walnut, Juglans nigra L., are harvested annually in the U.S. This production is based entirely on hand harvested nuts from seedling trees growing in native stands throughout the midwest and northeast. Significant improvement in nut quality and yield could be made for black walnut through the selection and propagation of superior clones. Cultivars have been identified that exhibit one or more of the important genetic traits needed for crop improvement. These traits include: lateral bud fruitfulness, late leafing, resistance to Gnomonia leptostyla (Fr.) Ces. & de Not., precocity, thin shell thickness, high percent kernel, ease of shelling, and light colored kernels. Cultivars that bear nuts on lateral branches and produce nuts with more that 30% kernel are currently available. If planted in an orchard situation, these cultivars could have an immediate impact on the black walnut industry. Commercial black walnut orchards based on thin shelled cultivars have not been developed due to the lack of cultivar performance data and undemonstrated crop profitability. Large trial plantings that become financial successful will be necessary to stimulate a black walnut orchard industry. The incorporation of additional positive traits into walnut cultivars will only be made after an established walnut industry demands further crop improvement.
NEW THINNER CHEMISTRY FOR PEACHES AND APPLES
Authors: Byers Ross E.
Published: April 2024

Several classes of chemicals (auxins, cytokinins, gibberellins, ethylene releasing compounds, photosynthetic inhibitors, pollination inhibitors, and carbamates) have been found effective for reducing fruit numbers on apple and/or peach trees. The selection of a chemical for use as a commercial thinner is usually based on consistent effectiveness, freeness from fruit, leaf or tree injury, increases in fruit size, and low degree of environmental influences on fruit thinning or injury. In recent years research has been curtailed on newer chemicals due to the small and unique market, the costs of chemical registration, and non-support of the chemical industry due to potential law suits from over or under thinning. Recommendations that include the use of combinations, adjuvants or timings inconsistent with the existing label will likely become more difficult than in the past. Our results with Wilthin, YI1066, MYX6121, endothall and ammonium thiosulfate have been very positive as bloom thinners for peach. Further research is needed to determine which of these have the least injury for apples. In addition, we have considerable interest in Oxamyl and 6-benzyladenine for thinning apple fruit and their combinations with existing thinners and adjuvants.
CHEMICAL THINNER RESULTS ON `GALA' AND `FUJI' APPLES
Authors: Micke Warren , Grant Joseph , Yeager James
Published: April 2024

`Gala' and `Fuji' apples are being extensively planted and are rapidly becoming important cultivars in California. `Gala' requires early and precise fruit thinning to produce good size and quality fruit. Preliminary studies indicated that this cultivar might be relatively easy to chemically thin with a program similar to that used for the `Granny Smith' cultivar in California. `Fuji' is subject to severe biennial bearing and must be thinned early. However, previous research has shown it to be a difficult cultivar to chemically thin. High rates and/or combinations of materials showed promise of effective fruit thinning of `Fuji' in limited trials in 1992, but not without phytotoxic effects of “pygmy” fruit, reduced fruit size and fruit russetting and marking. More extensive trials with both `Gala' and `Fuji' are planned for 1993 and preliminary results from these trials will be reported at this workshop.
MANAGING HIGH VIGOR IN BEARING ORCHARDS: CONTROLLING GROWTH WITH ETHEPHON
Authors: Byers Ross E.
Published: April 2024

Ethephon application at rates of 1000 ppm to 1500 ppm substantially inhibited tree growth but also caused fruit abscission. Application of gibberellin plus ethephon did not prevent fruit abscission. Low weekly doses of ethephon did not cause fruit abscission but gave good control of tree growth. Ethephon increased soluble solids and substantially reduced starch in the year of application. Flowering and fruit set were greatly increased by ethephon sprays the previous season. Fruit diameter or length:diameter ratios (L/D ratio) were not altered by the previous seasons' low weekly doses of ethephon.

Complete or partial loss of fruit in high density apple plantings can result in excessive shoot growth that is normally controlled by cropping. Spot spraying with ethephon in the top part of `Redchief Delicious'/MM. 26 trees for tree training purposes increased the number of shoots over 10 cm in the lower part of the tree, but also caused fruit abscission in the unsprayed parts of the tree. Summer training of high density plantings of fireblight susceptible varieties with spot sprays of ethephon would reduce the need for cutting or pinching branches during the tree growth period.
TEACHING PLANT TISSUE CULTURE TECHNIQUES AND EXPERIMENTS
Authors: Kamp-Glass Marihelen
Published: April 2024

With the expansion of agriculture biotechnology, plant biotechnology has become increasingly popular as a means of producing commercially useful crops for consumption and research. The ability to perform research on crops requires a basic understanding of the techniques of plant cell and tissue culture for genetics and other areas of plant physiology and horticulture. Teaching basic plant tissue culture techniques such as aseptic techniques, media preparation, explant orientation, callus induction and embryo culture will be discussed.
HURRICANE ANDREW DAMAGES TROPICAL FRUIT CROPS IN SOUTH FLORIDA
Authors: Campbell Richard , Campbell Carl , Crane Jonathan , Balerdi Carlos , Goldweber Seymour
Published: April 2024

On 24 August, 1992, Hurricane Andrew struck South Florida's tropical fruit production area with sustained winds of 230 kph and gusts exceeding 280 kph. Damage included defruiting, defoliation, limb and trunk breakage, windthrowing (uprooting), sunburning and the stripping of bark from the trunks and limbs by flying debris. In general, older and taller trees were more severely damaged than younger and shorter trees. Selective limb removal, topping and other pruning practices that reduced overall tree height and opened up the canopy greatly reduced the occurrence of windthrow and severe breakage. Severe damage occurred on lime, mango, passion fruit, lychee and longan; damage was moderate on atemoya, avocado, banana, mamey sapote, papaya and sugar apple; and light damage occurred on carambola and guava. The full extent of injury cannot yet be determined as additional losses will occur due to the direct trauma of the hurricane, insects and diseases, cold temperatures and drought.
CHROMOSOME DOUBLING OF INTERSPECIFIC F1 HYBRIDS BETWEEN Allium fistulosum × A. cepa THROUGH COLCHICINE TREATMENT OF REGENERATING CALLUS
Authors: Song Ping , Kang Wanhee , Peffley Ellen B.
Published: April 2024

Regenerating calli of Allium fistulosum × A. cepa interspecific F1 hybrids were treated in vitro with colchicine. A factorial experiment (colchicine concentration × time) was used to recover tetraploids from in vitro colchicine treated calli. Shoot production of regenerating calli following in vitro colchicine treatment decreased with increasing colchicine concentration and treatment time. Cytological analyses of root tip cells from regenerated plantlets showed that chromosomes of control plantlets (not treated with colchicine) were not doubled. Chromosomes of some plantlets regenerated from in vitro colchicine treated calli were doubled, resulting in tetraploids. Calli treated with 0.1 or 0.2% colchicine in BDS (Dunstan & Short, 1977) liquid medium for 48 or 72 hours yielded the highest number of tetraploid plantlets. These results demonstrate that in vitro colchicine treatment of regenerating calli of interspecific F1 hybrids is effective in recovering tetraploids.
INFLUENCE OF Fe CHELATES AND pH ON HEAT-INDUCED CHLOROSIS IN SEEDLINGS OF HONEY LOCUST
Authors: Graves William R. , Green Carrie E.
Published: April 2024

We observed previously that a root-zone temperature (RZT) of 34C caused severe chlorosis of Gleditsia triacanthos L. var. inermis Willd. (thornless honey locust) grown in solution. To determine whether the form of Fe chelate or the solution pH influence chlorosis, we measured growth, chlorophyll (Chl) content, and essential elements in solution-cultured seedlings treated with different chelate forms (Fe-EDTA, Fe-EDDHA, or no Fe), pH (5.4 or 7.0 upon weekly replacements), and RZT (23 or 34C). Chelate form and pH did not affect the development of chlorosis. Reductions of at least 50% Chl were induced by high RZT. Concentrations of P, Mg, Zn, Mn, and Fe in lamina were affected by RZT. Fe treatments caused Mg, Zn, Mn, Cu, and Fe concentrations to differ. Solution pH increased between replacements even in solutions without Fe, indicating that Fe-deficiency responses in this species merit further attention.
THE EFFECT OF SOME MICRONUTRIENTS ON THE YIELD AND FRUIT QUALITY OF WHITE BANATY SEEDLESS GRAPE VINES
Authors: Akl Ahmed M. , Wassel Abdul Mamed , Eid Abdul Fattah , Massan Massan M.
Published: April 2024

This experiment was carried out during the consecutive seasons of 1989 and 1990 at Minia Covernorate Egypt to study the effect of foliar application with Fe, Zn, Cu, and Mn (in sulphate form) each singularly and in all the possible combinations using three different concentrations (namely; 0.0, 300, and 600 ppm) on bud behavior and some vegetative and fruiting characteristics of White Banaty seedless grape-vines. Under the conditions of the study, spraying White Banaty seedless grapevines with Fe, Zn, Cu, and Mn together each at 600 ppm is recommended to obtain the highest yield and retention of fruit quality.
SUSTAINABLE PRODUCTION SYSTEMS -- OVERSEEDING AND TILLAGE EFFECTS ON WEED SUPPRESSION AND BROCCOLI YIELD
Authors: Serage Tammam , Morse Ronald
Published: April 2024

Experiments were conducted at two sites in Virginia to study the effects of tillage (conventional plow-disk and no-tillage) and overseeding of legume cover crops (red clover, Trifolium pretense L.; white clover, Trifolium repens L.; and hairy vetch, Vicia vellosa Roth.) at transplanting on weed suppression and yield of `Big Sur' broccoli (Brassica oleracea var. Italica Plenck). In both sites, weed suppression from overseeding was as good and in some cases superior to that in the herbicide-treated control plots. With the exception of hairy vetch in site 2, overseeding did not reduce broccoli yield. Weed suppression and broccoli yield were unaffected by tillage system and there were no tillage × overseeding effects. Based on our data, overseeding legumes could be an important component of our no-till system as we move towards more sustainable production methods for vegetables.
SENSITIVITY OF TOMATO AND BELL PEPPER TRANSPLANTS TO AN ORGANIC HERBICIDAL PRODUCT
Authors: Prince Carolyn A. , Christians Nick E.
Published: April 2024

The purpose of this study was to determine the growth response of tomato (Lycopersicon esculentum Mill.) and bell pepper (Capsicum annuum L.) transplants to corn gluten meal, an organic by-product of the corn wet milling process with allelopathic and herbicidal properties. Replicated greenhouse studies were conducted to evaluate the effect of corn gluten meal applied at rates of 0, 2, 4, 6, 8, and 10 grams/plant to 5, 6, or 7 week old transplants. Shoot dry weight, root dry weight, and total leaf area decreased as the rate of corn gluten meal increased in the five week old tomato transplants. When the transplants were six or seven weeks old differences in shoot and root dry weights were similar for all treatment rates. Significant differences in shoot dry weight and leaf area of the 5, 6, or 7 week old bell pepper transplants were not observed. However, root dry weight of 5 week old bell pepper transplants decreased with increasing rates of corn gluten meal.