bluuebunny/crossref_metadata_2025 huggingface dataset:
USE OF CLONALLY REPLICATED SEEDLINGS IN FIELD SCREENING FOR RESISTANCE TO PEACH TREE SHORT LIFE
Authors: Okie W.R. , Beckman T. G. , Nyczepir A.P.
Published: February 2019

Lovell rootstock is recommended for Peach Tree Short Life (PTSL) sites in the Southeast because it outlives Nemaguard. No genetic studies of PTSL tolerance have been done. Clonally replicated peach seedlings [Prunus persica (L.) Batsch] of Lovell, Nemaguard and four F1 selections of Lovell × Nemared were tested for field survival in a high density planting on a PTSL site. Rootstock families (12 seedlings × 8 ramets each) differed in growth, survival and longevity. Genetic variation was comparable to environmental variation for most families. Based on seedling within rootstock family, estimated broad-sense heritabilities for survival and longevity were high. The use of clonally replicated seedlings allowed the selection of apparently superior individuals from both Lovell and the other more short-lived rootstock families in a single screening after 6 years. Survival of Lovell at that time was 50% compared to 16-29% for other families. Across all families, all 8 ramets were dead for 21 seedlings, whereas all 8 were alive for only 3 seedlings.
MOLECULAR CLONING OF cDNA-ENCODING SORBITOL-6-PHOSPHATE DEHYDROGENASE FROM APPLE
Authors: Kanayama Yoshinori , Mori Hitoshi , Imaseki Hidemasa , Yamaki Shohei
Published: February 2019

Sorbitol plays a important role in the translocation of photosynthate in apple. Sorbitol-6-phosphate dehydrogenase (S6PDH, is the key enzyme regulating sorbitol biosynthesis. The cloning of functional gene like S6PDH provides the potential to elucidate the mechanism of production and translocation of sugar in the Rosaceae family and to manipulate endogenous sorbitol production in horticultural crops.

Poly(A)+RNA was prepared from apple seedlings and cDNA library constructed in an expression vector was screened by the loquat-S6PDH antibody prepared by Hirai (Natl. Res. Inst. Veg. Ornam. Plants & Tea, Japan). The cloned cDNA contained an open reading frame of 930 base pairs encoding a sequence of 310 amino acids. Identification of the cDNA was accomplished by expression of active enzyme in Escherichia coli harboring the cDNA and by the presence of a partial amino acid sequence identical to that found in the purified enzyme. Northern blot analysis showed the expression of S6PDH gene in apple seedlings.
NH4/NO3 MIXTURES ENHANCE GROWTH IN POTATOES
Authors: Cao W. , Tibbitts T.W.
Published: February 2019

The effects of various NH4-N/NO3-N ratios on growth and mineral accumulation in potatoes (Solanum tuberosum cv. Norland) were investigated using a nutrient film technique. Plants were grown for 35 days after transplanting at six NH4-N/NO3-N mixtures of 0/100%, 20/80%, 40/60%, 60/40%, 80/20%, and 100/0% with the same total N concentration of 4 mM. All mixed N treatments significantly increased total and tuber dry weights, plant size, leaf area, and specific leaf area as compared to either NH4 or NO3 alone. Plant growth was better with NO3 alone than with NH4 alone. Compared with mixed N treatments, total N concentrations in shoots were lower with either N form alone whereas total N in roots was lower only with NO3 alone. With increased percentages of NH4, root nitrate N concentrations decreased, and reduced N increased. The NO3 alone treatment increased concentrations of Ca, Mg, Fe and Mn, and reduced concentrations of P, S, Cl, B, Zn and Cu in shoots as compared with NH4 and mixed N treatments. It is concluded that a proper maintenance of both NH4 and NO3 forms can potentially promote growth and yield in potatoes.
PAPAYA FRUIT DEFORMATION AS RELATED TO BORON DEFICIENCY
Authors: Nishina M.S. , Nagao M.A.
Published: February 2019

Nutrient field studies were conducted on papaya, Carica papaya `Kapoho Solo' under rocky soil conditions in Puna, Hawaii. The objective of the study was to establish the relationship between boron (B) petiole tissue levels of trees with deformed and normal fruits. Field surveys indicated that trees with deformed fruits had 25% less B than normal trees. A 4.05 hectare field was treated with rates of 0, 1.12, 3.92 and 5.04 kilograms of B per hectare. By-weekly tissue results showed that B levels increased from 4 to 10 weeks after application with the 16 week levels substantially higher than the control trees. The results showed that maintaining the tissue B levels over 25 ppm B corrected the deformed fruit condition of papaya. Commercial fertilizer blends have been formulated with 0.3% B which is now used semi-annually on all commercial plantings.
ETHIDIUM BROMIDE INHIBITION OF NAA-INDUCED ROOTING IN MUNG BEAN CUTTINGS
Authors: Witham Francis H. , Heuser Charles W. , Chen Jun
Published: February 2019

Ethidium bromide (EB), at 10-5 to 10-4 M, progressively inhibits NAA-induced rooting of mung bean cuttings. Cycloheximide (CH), 6-methylpurine (6-MP) and kinetin (KIN) also inhibited rooting at the same concentrations, although CH and 6-MP were more effective.

At 70 and up to 130 hours of incubation, after cuttings received a 1-ml pulse of NAA (10-4 M), they exhibited a progressive increase in the number of observed adventitious roots. The addition of one of the inhibitors, 6-MP, EB or KIN to cuttings, pulsed 48 hours earlier with NAA, showed an initial slight inhibition with increased inhibition over time. CH, however, inhibited rooting immediately after addition. From these and other similar kinetic studies, it appears that 6-MP, EB and KIN operate at the transcriptional level and that CH inhibits translation.

Lineweaver-Burk plot analysis of NAA-induced rooting inhibition showed that EB may act as a competitive inhibitor of NAA. Since EB is a known intercalating agent and competitively inhibits NAA-induced rooting, NAA may influence gene expression by ultimately binding to DNA. Studies with space-filling and computer-generated models show that both NAA and EB can bind to certain dinucleotides by an intercalation mechanism.
WATER IMBIBITION AND RADICLE GROWTH OF GERMINATING PEA, CORN, AND SOYBEAN SEEDS ORIENTED TO THE EAST, SOUTH, WEST, AND NORTH IN SIX DIFFERENT MAGNETIC FIELDS
Authors: Liang Benjamin , Brown John M.
Published: February 2019

Magnetic Resonance Imaging (MRI) is currently considered as a nondestructive and noninvasive method for observing the distribution, concentration, and status of water in biological materials. However, effects of static magnetic fields of MRI systems on plant growth and development remain controversial. This study was conducted to investigate the water imbibition and radicle growth of Pisum sativum (cv. Little Marvel), Zea mays (cv. Pioneer 3379), and Glycine max (cv. Forrest) seeds oriented to four directions and exposed to six different magnetic field strengths commonly used in MRI systems.

Seeds were embedded in a water saturated synthetic foam medium, and were oriented, with respect to their hilum or embryo, to the east, south, west, or north. Seeds were then exposed to either 2, 4, 6, 8, 10, or 15 kilogauss static magnetic fields for 48 hours (water imbibition) or 54 hours (radicle growth).

The orientation of seeds and the magnetic field strengths had no effect on water imbibition or radicle growth of seeds tested. However, long term exposure retarded pea radicle growth in 2 KG treatment, enhanced soybean radicle growth in 10 KG treatment, but had no effect on corn radicle growth.
MEASURING MOTIVATION AND WORK CHARACTER PROFILE OF INMATE/PROBATIONERS IN A HORTICULTURAL COMMUNITY SERVICE WORK DETAIL PROGRAM
Authors: Shoemaker Candice A. , Breault John Paul
Published: February 2019

A community service work detail program has been established at a state regional hospital to assist the Horticultural Therapy Program. The program provides a stimulating environment, job training, and a work setting for the inmate/probationer. The primary goal of the program is to reduce the number of repeat offenders reentering the criminal justice system.

Evaluation at entry into the program and after every 200 hours was conducted to define a work character profile and prioritize motivational drives. Interest and motivation in the program increased the first 600 to 800 hours and then decreased. To be effective, community service hours in a horticultural work detail program should be no more than 800 hours. The inmate/probationers were prepared and ready to reenter the community work force at this time.
CONSUMER HORTICULTURE EXTENSION PUBLICATIONS IN THE U.S. - 1992
Authors: Crater G. Douglas , Colt Michael , Lerner B. Rosie , McLaurin Wayne , Sharp Denise
Published: February 2019

A list of the consumer horticulture publications available from the cooperative extension service of each state was compiled. This list was prepared under the auspices of the ASHS Extension Consumer Horticulture Working Group and will be available for distribution. This list includes extension publications, leaflets and other extension materials appropriate for continuing education programs in consumer horticulture.
MONSOON PLANTING OF POTATOES: A NEW CROPPING PATTERN FOR THE ARID HIGH HILLS OF WESTERN NEPAL
Authors: Khatri Bhim B. , Shakya Janak D. , Lorenzen James H.
Published: February 2019

Potato (Solarium tuberosum L.) is a major food crop for farmers of higher elevations (> 2000 m) in Nepal. Farmers plant potatoes in early spring after snow melt, utilizing residual winter moisture and occasional pre-monsoon rains for crop growth. The growing season is usually ended by late blight (LB, Phytophthora infestans) after the onset of the monsoon. However, drier areas of the interior of W. Nepal regularly experience drought and impaired plant growth before the monsoon, and the lesser duration and intensity of the monsoon there should result in lower LB pressure with a June/July planting.

Planting just prior to the monsoon in highland areas with annual rainfall < 1000 mm has given outstanding yields with cvs Achirrana Inta and I-1124. On-station and farmers' field trials have produced over 40 and 30 T ha-1, respectively, more than 4x the national average yield and nearly 2x the equivalent yield for a normal season planting in the same site. The LB resistant cultivars and the new cropping pattern may be extended to similar sites. (Supported by Swiss Devel. Assistance & Humanitarian Aid, Bern, Switzerland)
EVALUATION OF WATER CONSERVATION POTENTIAL OF NON-TURF GROUNDCOVERS VS. KENTUCKY BLUEGRASS UNDER INCREASING LEVELS OF DROUGHT STRESS.
Authors: Staats David , Klett James E.
Published: February 2019

In June 1991, a two year field study was initiated to examine if three non-turf groundcovers with reputations for using low amounts of water actually use less water than Kentucky bluegrass (KBG). Irrigation treatments were based on percentages of ET (100%, 75%, 50%, 25%, 0%) and calculated by the modified Penman equation. Results from the 1991 season indicate that at the 100% and 75% treatments Potentilla tabernaemontani and Cerastium tomentosum were significantly better than the other species in terms of establishment and vigor but quality declined significantly at rates below 75%. At the 50% rate both KBG and Sedum acre maintained good quality although growth was slow. At the 25% rate, quality of KBG significantly declined while Sedum acre maintained good quality. Quality of Sedum acre declined only slightly at the 0% treatment and would be a good alternative to KBG if water conservation was a high priority in the landscape.
TOLERANCE OF NECTARINE AND PEACH CULTIVARS TO INSECTICIDAL CONTROLLED ATMOSPHERES
Authors: El-Wazir Fairuz. , Ke Dangyang , Kader Adel A.
Published: February 2019

The tolerances (based on time before detection of off-flavor) of nectarine and peach cultivars to an insecticidal controlled atmosphere of 0.25% O2 (balance N2) at 20C were 2.8, 4.0, 4.0, 4.4, 5.1, and 5.3 days for `John Henry' peaches, `Fantasia' nectarines, `Five Red' peaches, `O'Henry' peaches, `Royal Giant' nectarines, and `Flamekist' nectarines, respectively. The greater sensitivity of `John Henry' peaches to low O2 stress was associated with a higher respiration rate; faster accumulation rates of acetaldehyde, ethanol, and ethyl acetate; and a more mature and larger fruit. The tolerances of `Fairtime' peaches to 0.21% O2 + 99% CO2 at 20C, 0.21 O2 + 99% CO2 at 0C, and 0.21% O2 at 20C were 3.8, 5.0, and 6.0 days respectively. There was a good correlation between tolerance of nectarines and peaches to insecticidal atmospheres and the accumulation rates of acetaldehyde (r=-0.94, p<0.01) and ethanol (r=-0.88, p,0.01).
INHERITANCE OF DIAPHORASE AND GLUCOSE-6-PHOSPHATE ISOMERASE IN EUSTOMA GRANDIFLORUM
Authors: Rubino David B.
Published: February 2019

Segregating progenies from controlled pollinations of Eustoma grandiflorum Griseb. were investigated to determine the inheritance of diaphorase (DIA) and glucoses-phosphate isomerase (GPI) isozymes. Phenotypic data supported the hypotheses that DIA1 is tetrameric and is controlled by a single locus with two alleles (Dia1-1 and Dia1-2) and that GPI1 is dimeric and also is controlled by a single locus with two alleles (Gpi1-1 and Gpi1-2). Examination of isozyme phenotypes for over 70 cultivars of E. grandiflorum revealed polymorphism for DIA1 and GPI1. These isozymes may be useful for marker-assisted selection and cultivar identification.
INVESTIGATION OF NATIVE ORNAMENTAL RESOURCES IN MOUNT HUANGSHAN (EASTERN CHINA)
Authors: YU Shujun
Published: February 2019

The author investigated, recorded, observed and analyzed the major wildflowers in Mount Huangshan---the natural and cultural heritages listed by the ESC0 of UN for the first time. On the basis of their desirable characteristics, more than 300 wild ornamental species are divided into 8 categories -–-historical old trees, rare and endangered species, evergreen ornamentals, blooming trees and shrubs, plants with colored foliage and fruit in fall, vines, herbaceous ornamentals and ground covers, and ornamental ferns. Mount Huangshan is one of the richest regions of native ornamentals in Eastern China and the most famous natural beauty in Pan-China. There are about 1500 wild landscape plants in and around it. Finally the paper puts forth some proposals and methods for introduction and utilization of wild ornamental plants. That is, investigation, classification,acclimatization and cultivation of them, and building a sort-out botanical garden for the germplasmic preservation and the flourishing landscape tourism.
PLANT GROWTH IN COAL GASIFICATION SLAG-AMENDED MEDIA
Authors: Holcomb E. Jay , Walker Paul N.
Published: February 2019

Coal gasification slag is an ash byproduct remaining after the volatization process. This material is currently under utilized. A series of experiments were conducted to determine the suitability of coal gasification slag as a growing medium or growing medium amendment. Chrysanthemums, lettuce, poinsettias and some bedding plants were grown in slag or slag amended media in an ebb and flow fertigation system. Slag alone has a high pH and initial slag samples had some very small particle sizes. Plant growth in slag alone was poor because of high pH and low aeration. When slag was amended with moss peat, the pH was lowered to an acceptable range and the aeration was better. Plant growth in peat-slag media was equal to plant growth in a peat-perlite mix. Media composed of peat-slag and bark were also successful in producing crop growth equal to peat-perlite. There were no nutritional problems growing in slag amended media except that boron uptake by chrysanthemum was greater than in other media. Eliminating the small particle sizes by washing the slag makes the slag easier to handle, but does not produce crop growth equal to slag amended media.
FURTHER EVIDENCE THAT THE LEGUME CLADRASTIS KENTUKEA (AMERICAN YELLOWWOOD) DOES NOT FORM NITROGEN-FIXING SYMBIOSES WITH RHIZOBIA
Authors: Graves' William R. , van de Poll Wilhelmina
Published: February 2019

The capacity to form nitrogen-fixing symbioses with rhizobia is common among species in the Papilionoideae subfamily of the Leguminosae, but nodulation and nitrogen fixation have never been documented in Cladrastis kentukea (Dum.-Cours.) Rudd (American yellowwood). The purpose of this study was to test the hypothesis that C. kentukea is nodulated by rhizobia. Seedlings were grown in sterile vermiculite and irrigated with a nitrogen-free nutrient solution. In one experiment, the vermiculite was inoculated with rhizobia that nodulate Maackia amurensis Rupr. & Maxim., a closely related tree species. During a second experiment, the vermiculite was inoculated with samples of soil collected near trees of C. kentukea in a native stand in Alexander County, Illinois. There were no nodules on roots of seedlings harvested 6 weeks after inoculation in either experiment. These results represent strong additional evidence that C. kentukea does not form nitrogen-fixing symbioses with rhizobia.
ANTHURIUM HYDATHODE STRUCTURE AND GUTTATION OF GLUTAMINE IN RELATION TO NITROGEN NUTRITION AND RATE OF BACTERIAL BLIGHT INFECTION
Authors: Sakai William S. , Okimoto Stacy , Sakai David S. , Hanohano Trudy
Published: February 2019

Infection of Anthurium andraeanum Andre by Xanthosomas campestris pv. dieffenbachiae appears to be through hydathodes. Hydathodes occur around the entire margin of the leaves. A small vein that runs parallel to the margin delimits the outer edge of the mesophyll chlorenchyma and the inner edge of the hydathode. External to the vein, epithem cells and intercellular spaces occur adjacent to the xylem vessel elements. Hydathode pores mostly occur on the adaxial surface of the leaf margin. Hydathode structure is consistent and does not appear to differ among cultivars. Glutamine may occur in the guttation liquid with higher levels of nitrogen nutrition. At the same level of nitrogen, more susceptible cultivars appear to produce more glutamine than cultivars more tolerant to the blight. More glutamine appears to increase the rate of blight infection.
GROWTH REGULATORS AND PRUNING AFFECT FLOWER AND FRUIT DEVELOPMENT IN COFFEA ARABICA L.
Authors: Schuch Ursula K. , Fuchigami Leslie H. , Nagao Mike A.
Published: February 2019

Unsynchronized flowering and fruit ripening of coffee prohibits mechanical harvesting and results in high labor costs. Coffee (C.arabica c. Guatemalan) trees were sprayed at the beginning of the 1988 and 1989 flowering season with solutions of benzyladenine (BA), gibberellic acid GA3 (GA), and Promalin (PR) or were pruned in 1988 to determine effects on synchronizing flowering and ripening. Growth regulators affected the time to flowering and harvesting compared to the control, however, treatment effects were dependent on the time of growth regulator application. Application of PR and GA at 100 mg/l in Jan 1988 shortened the average days to flowering by 16 and 13 days, and the average days to harvest by 15 days compared to the control. Pruning of three apical nodes of primary lateral branches in Feb 1988 caused delays in flowering, reduced flower and fruit number per tree, and caused branch dieback.
EMBRYOGENESIS IN EGGPLANT COTYLEDON CULTURE
Authors: Bastaki Shahraban , AboEl-Nil Mostafa , Abdal Mahdi
Published: February 2019

Eggplant (Solanum melonga L.) cotyledons were used to form somatic embryos for somaclonal induction and for selection of salt tolerant genotypes in a genetic improvement program. Naphthalene acetic acid at concentrations ranged from 5 uM to 85 uM induced embryogenesis when cultures were incubated under 16 hrs of light photoperiod. NAA was the only growth regulator required, and the addition of kinetine and benzyl adenine inhibited embryo formation. High frequency embryogenesis formed in 2 week old cotyledons when cultured on a medium supplemented with 43 uM NAA. Data showed that varieties varied in their embryogenesis potential and that cotyledons were the most responsive tissue. Somatic embryos germinated into plantlets when transferred into media without any growth regulators. Somatic embryos were plated on germination media supplemented with Kuwait brackish water to increase the total dissolved salts in the medium from 4,770 ppm to 30,000 ppm in seven equal increments. Brackish water at all concentrations caused embryos to revert into profuse callus growth.
RAPID MICROPROPAGATION OF COCOYAM (XANTHOSOMA SAGITTIFOLIUM SCHOTT)
Authors: Sama Anne E. , Hughes Harrison G.
Published: February 2019

Shoot tips, approximately 3-5mm, were isolated from corms of young greenhouse-grown plants of cocoyam, cultivar South Dade White. After preliminary evaluations, the initiation media evaluated were B5 basal salts supplemented with 0.05 μM NAA with 5μM BAP, 20μM BAP or 2μM TDZ. The above media were in the form of liquid medium in flasks on a rotary shaker, liquid medium with filter paper bridges, stationary liquid medium without filter paper and solidified medium with 0.4% agar. TDZ stimulated greater growth with multiple shoot formation. Liquid media either in the shaker or stationary form were more effective in terms of growth. Shoots were subsequently evaluated for multiplication with 1μM TDZ and 5μM BAP with 0.05μM NAA producing greater shoot numbers. Over 30 plants have subsequently been rooted and acclimatized under mist or humidity tent.
USE OF A HIGH CO2 ATMOSPHERE FOR MICROPROPAGATION OF PISTACHIO
Authors: Parfitt D.E. , Almehdi A.A.
Published: February 2019

An improved medium for the in-vitro micropropagation of P. vera genotypes was developed. Several basal medium preparations were tested and DKW (Driver-Kuniyuki-Walnut) medium was selected. Macro and micronutrients were adjusted to provide optimum growth and multiplication of shoots, some of which have been grown and multiplied for more than 2 years. The use of thidiazuron as a growth regulator was tested, but was detrimental to the explants at all tested concentrations. Initial experiments were hindered by significant bacterial internal contaminants. This problem was eliminated through the use of plexiglass chambers to provide up to a 20,000ppm CO2 atmosphere, increased light levels to promote photosynthesis, and the elimination of all carbon sources (sugars) from the substrate. An additional benefit was better shoot growth, better survival when rooting and better acclimation. 3/7 plants were rooted using 2.5 ppm IBA. Continuing experiments are focused on the effect of support medium on growth and multiplication as well as media development for other Pistacia species.
CALLUS INDUCTION IN SOMATIC TISSUES OF PRUNUS PERSICA L.
Authors: Declerck Veronique , Korban Schuyler S.
Published: February 2019

Leaf segments of Prunus persica L. (peach) collected from greenhouse-grown plants and from micropropagated shoots were cultured on a basal medium containing half-strength Murashige and Skoog (MS), Staba vitamins, sucrose (30 g/1) and agar (6.5 g/l); medium adjusted to pH 5.6. The influence of 6 different growth regulators at 3 concentrations (5, 10, 15 μM) were investigated using leaf explants from proliferating shoots of 'Elberta Queen' peach. With thidiazuron (TDZ), compact and multiple green calli were obtained; with benzyladenine and zeatin, lower numbers of small sized calli were obtained; with kinetin, no callus development was observed. Among auxin treatments, both Dicamba and 2,4-D resulted in friable white and yellow calli. Most of the calli produced in all treatments were formed along the cut margins of the explants. In an another experiment, leaf explants of' Bellaire' (greenhouse) and `Elberta Queen' (in vitro shoots) were used to determine the influence of a large scale concentration of TDZ (3 to 23 |iM). Explants from greenhouse and in vitro leaves resulted in higher levels of callus development at TDZ concentrations of 8-13 μM. Higher TDZ levels resulted in necrosis of leaf explants. The-influence of different carbon sources on callogenesis was investigated. We observed more green and compact calli with glucose than with sucrose and fructose at 100 mM. The influence of the glucose at 10 different concentrations (30 to 300 mM) was also investigated.
THE LIMITING FACTORS DETERMINING THE INTRODUCTION OF BIOTECHNOLOGY
Authors: Liu Jang R.
Published: February 2019

Commercial sources of biotechnology have enormously outweighted non-market sources (e.g. the International Agricultural Research Center) Thus it is most obvious that growing R&D costs and intensified internationa technology competition have financially disabled developing countries from access to the new technology. Furthermore, biotechnology is a typica interdisciplinary subject based on many different principles of newly developed life sciences such as biochemistry, physiology, microbiology and molecular biology, which limits number of personnel in developing countries who are capable of incorporating the new technological inovation o developed countries into their agricultural production system. The protection of intellectual property rights (IPRs) of which private firms in developed countries have intensified put another limiting factor in the international flow of biotechnology. Financial aid, technical assistance for personnel training and execution of self-restrained IPRs towards developing countries wil enable developed countries widen the potential market and contribute to sustainable development in the Third World.
Inheritance of Cold Germinability in Muskmelon
Authors: Hutton Mark G. , Loy J. Brent
Published: February 2019

A cold-germinable (CG) line of muskmelon (Cucumis melo L.) derived from PI 126156 was crossed to a noncold-germinable (NCG) line derived from `Delicious 51'. Seed of parents and reciprocal F1, F2, and BC families were incubated for 14 days on absorbent wadding in petri dishes at 15C. Days elapsed to radicle emergence among progeny from reciprocal crosses and segregating populations indicated the existence in the CG line of a cytoplasmic factor and recessive nuclear genes for cold germinability. Based on Fz and BC segregation, it appears that at least three or four recessive genes confer cold germinability. High levels of cold germinability in a seed population required the presence of both the cytoplasmic factor and nuclear genes for cold germinability.
Foliar-applied Molybdenum for Preventing or Correcting Molybdenum Deficiency of Poinsettia
Authors: Cox Douglas A.
Published: February 2019

`Annette Hegg Brilliant Diamond' poinsettia (Euphorbia pulcherrima Willd. ex Kl.) was grown in an unlimed growth medium consisting of equal volumes of sphagnum peat and perlite and received a fertilizer solution supplying all micronutrients except Mo. Plants were untreated or foliage was sprayed with solutions of 1, 10, or 100 mg Mo/liter 5, 8, or 11 weeks after pinching. Untreated plants developed foliar symptoms of Mo deficiency (marginal and interveinal chlorosis, marginal necrosis, and downward curling), and leaf tissue contained Mo below the critical level of 0.5 μg·g-1 and NO3-N > 1.0%. Treatment at 5 or 8 weeks largely prevented deficiency symptoms, increased tissue Mo, and reduced tissue NO3-N. Molybdenum deficiency symptoms were in the early stages of development on the day of treatment when plants were sprayed at 11 weeks. Molybdenum sprays at this time increased tissue Mo and reduced tissue NO3-N but did not eliminate the symptoms. However, when the experiment was completed 15 weeks after pinching, the number of leaves showing symptoms was about one-half that of untreated plants. Increasing the concentration of Mo in the spray solution increased the concentration of Mo in the leaves but had no effect on NO3-N.
Comparison of Flower Stalk Development in `Premier' and `Squire' Kale Cultivars
Authors: Taylor R.T. , Borchers E.A.
Published: February 2019

`Squire' Scotch kale (Brassica oleracea L.) (n = 9) and `Premier' smooth-leaved kale (B. napus L.) (n = 19) were planted in a field study to compare the onset and rate of flower stalk elongation after overwintering. Flower stalk elongation began 28 days later in `Premier' than in `Squire`; `Premier' plants remained marketable 24 days longer. In spite of the delay in the onset of stalk elongation, siliques of `Premier' were only 3 days later maturing.
Rapid Regeneration of Lettuce from Suspension Culture
Authors: Teng Whei-Lan , Liu Yann-Jiun , Soong Tai-Sen
Published: February 2019

An efficient method for the regeneration of shoots directly from cell suspensions of three commercial cultivars of lettuce (Lactuca sativa L. cv. Great Lakes 659-700, Salad Bowl, and Prize Head) is described. Cell suspensions were prepared by osterizing cotyledon-derived callus for 60 seconds. The effects of callus quality, light intensity, carbohydrate type and concentration, auxins, and cytokinins on cell growth and differentiation in the suspension culture were examined. Among these factors, callus quality and carbohydrates were the most critical. The optimal medium for regeneration of shoots in suspension culture was SH (Schenk and Hilderbrandt) basal medium containing 1000 mg myo -inositol/liter, 1.5% glucose, 0.44 μm BA, and 0.54 μm NAA. The pH of the medium was adjusted to 5.8. Under such condition, hundreds of shoots could be produced from 50 to 55 mg (dry wt) of cell aggregates within 2 weeks. Chemical names used: α-] naphthaleneacetic acid (NAA); indole3-acetic acid (IAA); 6-benzylaminopurine (BA).
Leaf Chlorosis and Seed Yield of Dry Beans Grown on High-pH Calcareous Soil following Foliar Iron Sprays
Authors: Zaiter H.Z. , Coyne D.P. , Clark R.B. , Lindgren D.T. , Nordquist P.T. , Stroup W.W. , Pavlish L.A.
Published: February 2019

Iron deficiency chlorosis (FeDC) causes extensive reduction in yields of edible dry beans (Phaseolus vulgaris L.) grown on high-pH and calcareous soils. Fifteen bean cultivars/lines differing in response to FeDC were grown 2 years (1988 and 1989) on a high-pH (8.0), calcareous (2.3% calcium carbonate equivalent in surface 20 cm), and low-Fe (2.2 mg Fe/kg) Typic Haplustolls silt loam in the field (central Nebraska) to determine the effects of FeDC on seed yield of cultivars/lines sprayed with Fe. A significant interaction (P < 0.05) between cultivars/lines × Fe spray treatment was noted for visual FeDC ratings in 1988 only, and no significant interactions were noted for seed yield either year. Sprayed cultivars/lines generally produced higher yields than unsprayed ones. Overall increases were 47% in 1988 and 41% in 1989. Even though only slight FeDC was noted on some cultivars/lines receiving no Fe spray, seed yields were significantly increased when sprayed with Fe. Some cultivars/lines with moderate or moderately severe FeDC ratings did not show a significant increase in yield when sprayed with Fe, while other cultivars/lines did. Seed yield reductions for the cultivars/ lines per unit of FeDC rating (1 = green to 5 = severe chlorosis) were 915 kg·ha-1 for unsprayed and 1518 kg·ha-1 for sprayed plants in 1988 and 344 kg·ha-1 for unsprayed and 608 kg·ha-1 for sprayed plants in 1989.
RELATIONSHIP OF PHOTOSYNTHESIS MEASUREMENTS TO FRUIT SOLUBLE SOLIDS AND SPECIFIC LEAF WEIGHT IN APPLE AND GRAPE WITH VARIOUS MEASURING TECHNIQUES
Authors: Popenoe Juanita , Baugher Tara Auxt
Published: February 2019

Photosynthesis, light (PAR) and transpiration were measured with an ADC portable infrared gas analyzer on apples and grapes. Measurements were taken on north and south sides of the rows, in the morning and afternoon, on sun and shade leaves, and with the leaf chamber in a horizontal position and in a natural leaf orientation position. Measurements were made on three cloudless days in August 1990 and 1991. Subsequently, fruit adjacent to sampled leaves were harvested and soluble solids determined. Sampled leaves were then harvested and leaf areas and dry weights measured. Correlation coefficients of variables were then subjected to analysis of variance to determine which techniques gave the best correlations. Grapes and apples responded differently. For grapes, soluble solids were most closely correlated to light and photosynthesis measurements when measured on south side shade leaves, while with apples, blush side soluble solids were best correlated with measurements on south side sun leaves in the afternoon. Specific leaf weight was best correlated to photosynthesis and light with grapes when measured on north side sun leaves and with apples when measured on the south side in the morning.
Foliar Heat Tolerance of Two Hybrid Hollies
Authors: Ruter John M.
Published: February 2019

Temperatures producing heat damage in leaves of Ilex ×meserveae S.Y. Hu `Blue Prince' and Ilex rugosa × cornuta Lindl. & Paxt. `Mesdob' (China Boy) were evaluated using electrolyte leakage and chlorophyll fluorescence techniques. Whole leaves were exposed to temperatures from 30 to 65C for 30 minutes to determine critical midpoint heat-killing temperatures (TJ using electrolyte leakage techniques. The Tm for `Blue Prince' and `Mesdob' was 52.4 ± 0.lC and 53.8 ± 0.lC, respectively. Dark-adapted leaves were heated for 30 minutes in darkness at temperatures between 30 and 57C before chlorophyll fluorescence was measured. Initial (F0) and peak fluorescence measurements were higher at 54 and 55C for `Mesdob' than for `Blue Prince'. Cultivar had no effect on variable fluorescence (F,). Based on the Fv: Fo ratio, `Mesdob' was estimated to have a higher optimal plant growth temperature than `Blue Prince'. The physiologic data support the hypothesis that I. cornuta as a parent conferred heat tolerance to the interspecific hybrid in this study.
Growth of Rooted `Gala' Apple Microcuttings ex Vitro as Influenced by Initial Adventitious Root Count
Authors: Stimart Dennis P. , Harbage James F.
Published: February 2019

The role of the number of adventitious roots of Malus domestics Borkh. `Gala' microcuttings in vitro on ex vitro root and shoot growth was investigated. Root initiation treatments consisted of IBA at 0, 0.15, 1.5, 15, and 150 μm in factorial combination with media at pH 5.5, 6.3, and 7.0. IBA concentrations significantly influenced final root count and shoot fresh and dry weights, but not plant height, leaf count, or root fresh and dry weights at 116 days. Between 0 and 0.15 μm IBA, final root counts were similar, but at 1.5, 15, and 150 μm IBA, root counts increased by 45%, 141%, and 159%, respectively, over the control. The pH levels did not affect observed characteristics significantly. There was no significant interaction between main effects. A significant positive linear relationship was found between initial and final root count. The results suggest a limited association between high initial adventitious root count and subsequent growth. Chemical name used: 1 H -indole-3-butyric acid (IBA).
Sources of Variation in Olive Flower and Fruit Populations
Authors: Martin G.C. , Nishijima C. , Early J.D.
Published: February 2019

Olive (Olea europaea L.) field experiments involving natural flower and fruit populations are fraught with variability, resulting in large coefficients of variation. We provide evidence that coefficients of variation can be reduced successfully by judiciously selecting four experimental twigs per tree and using only those twigs with an internodal growth ≥2 cm, two inflorescences per node, and that are selected from trees with near-maximum bloom density. Although counting flowers at full bloom may establish the population uniformity, only a single node; e.g., node 5, is needed for analysis. Increasing the number of trees will reduce variance more than increasing the number of twigs or nodes.
Cryopreservation of Ginseng Pollen
Authors: Zhang L.X. , Chang W.C. , Wei Y.J. , Liu L. , Wang Y.P.
Published: February 2019

Cryopreservation of pollen from two ginseng species —Panax ginseng L. and P. quinquefolium L.—was studied. Freezing anthers that served as pollen carriers to –40C before liquid N storage affected pollen viability little after liquid N storage. Anther moisture content affected pollen viability significantly when stored in liquid N. The ideal anther moisture content to carry pollen for liquid N storage was 32% to 26% for P. ginseng and 27% to 17% for P. quinquefolium. Viability of pollen from P. quinquefolium anthers with 25.3% moisture content changed little after 11 months of liquid N storage.
Plant Spacing Influences Watermelon Yield and Yield Components
Authors: NeSmith D.S.
Published: February 2019

Watermelon [Citrullus lanatus (Thunb.) Matsum & Nakai] cultivars StarBrite and Crimson Sweet were grown during 1991 and 1992 in rows 1.5 m apart at plant spacings of 0.9, 1.5, or 2.2 m. Total fruit yield, marketable fruit yield, fruit-weight distribution, and estimated gross returns were determined for each spacing treatment. Total and marketable fruit yields were greater overall for `StarBrite' than for `Crimson Sweet'. Except for 1991 `Crimson Sweet' yields, marketable fruit yields per unit land area increased 29% to 34% as plant spacing decreased from 2.2 to 0.9 m. The yield component contributing the most to increased yields with high-density plantings was increased fruit count per unit land area. Average fruit weight responded only slightly to decreased plant spacing. Fruit-weight distribution on a relative frequency scale was stable regardless of plant spacing or production year. The potential for increasing gross returns per unit land area exists by increasing watermelon plant populations beyond the current Georgia recommendation of 2500 to 3000 plants/ha.
Year-round Production of Flowering Calathea crocata: Influence of Light and Carbon Dioxide
Authors: Van Huylenbroeck Johan M. , Debergh Pierre C.
Published: February 2019

Programmed flower induction of Calathea crocata Morr. et Joris is possible under the controlled environmental conditions of a multilayer growing room. A photoperiod of 10 hours for 9 weeks, growth at 18C, and a photosynthetic photon flux density (PPFD) of 71 μmol·s-l·m-2 induced flowering in more than 95% of the plants and in 50% to 80% of the shoots. In the meantime, none of the plants under natural conditions was induced. Significantly more flowers were induced when PPFD during the short-day treatment was 71 rather than 56 μmol·s-1·m-2. Flowers became visible 14 to 16 weeks after the start of the inductive treatment. Moreover, raising the CO2 concentration to 900 ppm for 5 months increased the leaf area and dry weight by 40%, and resulted in darker leaf color, longer flower stalks, and significantly accelerated flowering (10 days).
Regenerating Plants from in Vitro Culture of Black Locust Cotyledon and Leaf Explants
Authors: Arrillaga I. , Merkle S.A.
Published: February 2019

A protocol to achieve efficient plant regeneration from juvenile black locust (Robinia pseudoacacia L.) explants is described. Direct adventitious shoots were induced from cotyledon explants on woody plant medium containing 22.2 μm BA and 0.4 μm 2,4-D. Shoots developed and new shoots were induced when the explants were transferred to medium without growth regulators. The effect of dark incubation on shoot regeneration from cotyledons indicated that 15 days of darkness resulted in a high regeneration frequency (91.7%). Adventitious shoot formation also was induced from sections of in vitro-derived leaves cultured in darkness on Murashige and Skoog medium supplemented with 4.4 μm BA and 24.6 μm IBA. A shoot regeneration frequency of 89% was obtained when explants were subcultured on a medium containing 4.4 μm BA and 0.5 μm IAA. Shoots were rooted on Schenk and Hildebrandt medium with or without IBA. Plantlets were acclimatized and grown in the greenhouse. Chemical names used: N -(phenylmethyl)-1H -purin-6-amine (BA); 2,4-dichlorophenoxyacetic acid (2,4-D); indole-3-acetic acid (IAA); indole-3-butyric acid (IBA).
Carbon Dioxide Treatment Partially Overcomes Self-incompatibility in a Cacao Genotype
Authors: Aneja Madhu , Gianfagna Thomas , Ng Edward , Badilla Ignacio
Published: February 2019

Cacao (Theobroma cacao L.) contains self-compatible and self-incompatible genotypes. In the greenhouse, pollen germination and fruit set failed to occur after self-pollination of an incompatible genotype (IMC 30); however, if the self-pollinated flowers were enclosed in plastic vials for 6 h after pollination, pollen germination was 95% The promotive effect of enclosed pollination on pollen germination was due to the accumulation of CO2 (8.9 % v/v). Despite the high rate of pollen germination, fruit set was only 45%. Seeds produced from self-pollinations using this technique were viable, with 95% germination. Cross-pollination with `Amelonado' pollen resulted in 100% pollen germination and 46% fruit set. Enclosure of cross-pollinated flowers did not improve the percentage of fruit set. Sections made through the ovary 48 h after enclosed self-pollination indicated that the majority of ovules contained a zygote; however, some ovules still contained unfused male and female gametes and polar nuclei. Self-incompatibility in this genotype is expressed at two stages in the process leading to fruit set. The first is at the pollen germination stage and can be overcome by CO2 treatment; the second is at the gametic fusion stage.
Rootstock-induced Differences in Sap Flow of `Granny Smith' Apple
Authors: Hussein Ismail A. , McFarland Marshall J.
Published: February 2019

Two-year-old, greenhouse-grown, potted `Granny Smith' apple (Malus domestica Borkh.) trees grafted on seedling, M.7 EMLA, or Mark rootstock were subjected to water stress by withholding irrigation for three successive days. Sap flow rates were measured with steady-state, heat-balance stem gauges; daily water use was measured with an electronic balance; and instantaneous transpiration was measured with a diffusion porometer. Differences in the sap flow among the three rootstocks were observed by the third day of stress treatment. The cumulative sap flow over the 3-day stress period was higher for trees on seedling and M.7 EMLA rootstocks than for those on Mark. Cumulative sap flow was reduced on the second and third days of water stress compared to sap flow in the control. The diurnal peak of sap flow rate was flattened on the second and third days of stress compared to the pattern for the control and first day of stress treatment. In general, the trees on the standard rootstock (seedling) were least affected by the water stress; trees on the full dwarf rootstock (Mark) were the most affected. Good agreement between cumulative sap flow measurements and gravimetric measurements indicates that the steady-state, heat-balance method is practical and accurate.
Nitrogen Concentrations Affect Pepper Yield and Leachate Nitrate-nitrogen from Rockwool Culture
Authors: Schon M.K. , Compton M. Peggy , Bell E. , Burns I.
Published: February 2019

Experiments were conducted to determine the effect of varying solution N concentrations on fruit yield and NO3-N concentration in leachate from rockwool-grown `Midal' peppers (Capsicum annuum L.) in Florida. Treatment 1 plants received a series of nutrient solutions containing N at 60, 90, and 120 mg·liter–1 (60–90–120 mg·liter–1) during their growth cycle. Plants in treatments 2 and 3 were grown with N at 120 or 175 mg·liter–1, respectively, throughout their entire growth cycle. Two trials were conducted; trial 1 from 17 Nov. 1991 to 1 July 1992, and trial 2 from 31 July 1992 to 23 Feb. 1993. In both trials, total marketable fruit weight was significantly (P ≤ 0.05) higher (16% to 67%) for plants grown with N at 175 than with 60–90–120 mg·liter–1. In trial 2, plants receiving N at 175 mg·liter–1 produced significantly more fruit (8%) and 14% higher total fruit weight than plants receiving N at 120 mg·liter–1. The trend toward higher yield with N at 175 rather than 120 mg·liter–1 also occurred during trial 1, but differences were not significant. Nitrogen concentration did not significantly affect the percentage of total fruit having blossom-end rot in either trial (41% in trial 1; 13% in trial 2). Nitrogen at 175 mg·liter–1 resulted in 10% to 40% increases in total nutrient solution use and 2.5- to 3.5-fold increases in leachate NO3-N concentration compared to N at 120 mg·liter–1.
Poultry Litter Quantity Influences Collard Growth in Pots and Affects Cabbage Growth and Nutrient Uptake
Authors: Lu Ningping , Edwards J.H.
Published: February 2019

A greenhouse pot study was conducted with a Wynnville sandy loam surface soil to determine the influence of application rates of poultry litter (PL) on growth and nutrient uptake of collard (Brassica oleracea, Acephata Group L., cv. Champion), and the residual effects of PL on growth and nutrient uptake of cabbage (Brassica oleracea, Capitata Group L., cv. Rio Verde). PL at 0, 13, 26, 53, and 106 g·kg–1 was incorporated into limed (pH 6.5) and nonlimed (pH 5.2) soil. Collard plants were grown for 52 days. The residual effects of PL were evaluated by growing three successive crops of cabbage without further application of PL (total 218 days). Collard plants were severely damaged or killed within 7 days after transplanting when the application rate of PL exceeded 26 g·kg–1 soil. Maximum dry matter yield of cabbage shifted from 26 to 106 g PL/kg soil during three successive crops. After four successive growth periods, 6% to 37% of N, 3% to 62% of Ca, 20% to 120% of K, 5% to 60% of Mg, and 3% to 25% of P added through PL was removed by plants. The decrease in water-extractable K accounted for the decrease in the soil salinity. Our results suggest that application rates of PL ≥ 53 g·kg–1 soil can result in elevated levels of salts and NH3 in soil, which can produce severe salt stress and seedling injury.
DCPTA Suppresses Growth and Flowering of Amaryllis
Authors: Meerow Alan W. , Svenson Sven E. , Kane Michael E.
Published: February 2019

DCPTA is a synthetically produced tertiary amine bioregulator with potential for increasing crop productivity at high light intensities. DCPTA reduces the number of days from planting to maturity in various potted ornamental crops, including `Fortune' daffodil (Narcissus L.), `Sonora' tulip (Tulipa L.), and `Jan Bos' hyacinth (Hyacinthus orientalis L.). Our objective was to examine how light intensity and DCPTA application influence growth and flowering of amaryllis (Hippeastrum hybridum Hort.). Flowering size bulbs of a micropropagated amaryllis clone were treated with 30 μm or no DCPTA and grown in full sun or 63% shade for 1 year. Number of scapes produced, flowers per scape, change in bulb fresh weight, number of bulblets produced, and bulblet weight were recorded and analyzed. There were no significant differences in days to first flowering or in number of flowers produced per scape among the treatments. DCPTA application at the recommended rate significantly reduced number of emergent inflorescences and the bulb biomass increase of hybrid amaryllis. Additionally, the interaction between light level and DCPTA appeared weak for amaryllis, and was only slightly significant relative to bulblet production. Chemical name used: 2-(3,4-dichlorophenoxy)triethylamine (DCPTA).
Chemical Repellents and Plastic Netting for Reducing Bird Damage to Sweet Cherries, Blueberries, and Grapes
Authors: Curtis Paul D. , Merwin Ian A. , Pritts Marvin P. , Peterson David V.
Published: February 2019

We conducted 3 years of field tests comparing two chemicals [methyl anthranilate (MA, a natural compound used as a flavor additive) and Keyplex-350 (a proprietary micronutrient formulation)] that were reported to repel birds to exclusionary plastic netting and nontreated plots. Cumulative fruit damage from birds was monitored on sweet and tart cherry (Prunus avium L. and P. cerasus L.), blueberry (Vaccinium corymbosum L.), and wine grapes (Vitis vinifera × labrusca). Initial MA formulations caused injury to fruit and foliage. Two modified MA formulations with microencapsulation and photooxidation inhibitors provided significant reductions in bird damage and fruit splitting on sweet cherries in one of four experiments. A taste panel could not detect MA residues on sweet cherries at harvest. Bird damage was slightly reduced in MA-treated grapes, but damage to blueberries was similar in MA and control treatments. Keyplex did not deter birds from feeding on fruit and caused blemishes on and an unpleasant flavor in treated fruit. Many bird species were observed feeding on these fruit crops during successive years at the three experimental sites. Although these two chemicals have the potential to deter bird depredation, our work suggests that neither is consistently effective against all the frugivorous species in the northeastern United States. Chemical name used: 2-Aminobenzoic acid methyl ester [methyl anthranilate (MA)].