bluuebunny/crossref_metadata_2025 huggingface dataset:
Propagation of Cordyline terminalis from Callus Culture1
Authors: Mee Grace W. P.
Published: September 2022

The Hawaiian ti plant, Cordyline terminalis (L.) Kunth, a woody ornamental plant, can be propagated in vitro from shoot tips, using several medium modifications (2, 3). Propagation of the ti plant can also be achieved by differentiation from callus tissue derived from young leaves near the apical meristem. Using this technique, it is possible to rapidly propagate ti plants to satisfy local needs and to supply foreign countries with large shipments of possibly disease- and pestfree plants. The procedure may be applicable to herbaceous as well as to woody monocotyledonous plants.
Root Regeneration of Manetti Rootstocks Grafted with Different Scion Cultivars of Rose1
Authors: Lee C. I. , Zieslin N.
Published: September 2022

An inverse correlation between number of roots regenerated and diameter of root segments (except fibrous roots) was found in Rosa ⨯ Noisettiana cv. Manettii. Length of regenerated roots was proportional to the diameter of root segments. The root-regenerating potential varied among scion cultivars. Manetti root segments regenerated best with rose scion cultivar ‘Cara Mia’, and least with ‘Golden Wave’.
Genetic Potential For Overcoming Physiological Limitations on Adaptability, Yield, and Quality in the Tomato
Authors: Allen Stevens M. , Rudich Jehoshua
Published: September 2022

Yield and quality are the primary goals of most plant breeding programs. Both of these general characteristics are multifaceted and extremely complicated. This complexity and a frequent negative relationship between them makes it difficult to deal successfully with them simultaneously in a breeding program.
Ripening Bananas with Ethephon in Three Polymeric Film Packages1
Authors: Liu F. W.
Published: September 2022

Ripening-initiated ‘Valery’ bananas (Musa sp.) held in gas mixtures containing 10 ppm ethylene, 2 to 10% O2 and 0 to 10% CO2, ripened at a slightly lower rate than in air and had comparable quality when ripe. Fruit ripened very slowly and had lower quality, however, when the O2 concentration was reduced to 1%. Ethylene gas, which was released from ethephon ((2-chloroethyl)phosphonic acid) solution applied to a small piece of sponge, initiated ripening of bananas in polymeric film packages. Three kinds of film regulated atmospheric composition inside packages suitable for banana ripening and holding. Making 1 or 3 pin holes through the film package increased the O2 concentration but had little effect upon CO2 and ethylene concentration. Bananas ripened with ethephon in suitable film packages had good eating quality and a longer shelf life than bananas ripened in air.
‘Elite’ Southernpea1
Authors: Bowers J. L. , Sistrunk W. A.
Published: September 2022

‘Elite’ (Vigna unguiculata (L.) Walp.), has been released by the Arkansas Agricultural Experiment Station, to meet the needs of gardeners and commercial processors for a well adapted cream type.
In Vitro Propagation of Cucumis sativus L.1
Authors: Handley Levis W. , Chambliss Oyette L.
Published: September 2022

Axillary buds of gynoecious cucumber (Cucumis sativus L.) were cultured on a semisolid medium containing Murashige and Skoog salts plus thiamin, pyridoxin, nicotinic acid, myo-inositol, and sucrose with 0.1 mg/liter naphthaleneacetic acid (NAA) and 0.1 mg/liter kinetin. Both shoots and roots were proliferated with little callus formation. Plants produced in vitro were successfully transferred to soil.
Effect of Nitrogen Source and Nitrapyrin on Sweet Corn1
Authors: Taber H. G. , Peterson L. E.
Published: September 2022

Sweet corn (Zea mays L.) showed no yield response for 2 years to spring applied Ν from Ca(NO3)2, urea, and urea plus nitrapyrin on a loam soil high in organic matter and cation exchange capacity. Ear leaf Ν concentration decreased with NH4-N sources in 1 year but not both. Kernel protein and leaf levels of P, K, Ca, and Mg were unaffected by treatment. On a loamy sand soil low in cation exchange capacity the NH4-N sources, compared with NO3-N, raised the kernel protein concentration by 0.26% both years. On this soil of the NH4-N sources, the addition of nitrapyrin to the urea band reduced ear leaf NO3-N levels without reducing ear leaf total Ν or kernel protein. The NH4-N sources restricted ear leaf Mg concentration but enhanced uptake of Ν both years and P and Κ in 1 year.
Effect of a Dormant Application of Surfactants on Bud Development and Disease Control in Selected Deciduous Fruit Plants1
Authors: Spotts R. A. , Ferree D. C.
Published: September 2022

Spray treatment a single dormant application of high concentrations of anionic (Triton CS7) and nonionic (Triton N57 and Triton X100) surfactants caused up to 5 days delay in bud break in apple (Malus domestica Borkh.), but had less effect on grape (Vitis spp.) and peach (Prunus persica (L.) Batsch) and none on pear (Pyrus spp.). Surfactants tended to extend the bud break period but were frequently lethal to buds, particularly at concentrations of 3% and 5% active ingredient. In field studies, surfactants delayed the early stages of flower bud development but not bloom of apple or peach and did not control apple scab caused by Venturia inaequalis (Cke.) wint. or powdery mildew caused by Podosphaera leucotricha (Ell & Ev.) Salm.
Effect of Lime on Yield and Keeping Quality of ‘McFarlin’ Cranberries1
Authors: Shawa Azmi Y.
Published: September 2022

Agricultural lime (CaCO3) was applied at rates of 0, 500, 1000, 1500, and 2000 kg/ha to ‘McFarlin’ cranberry (Vaccinium macrocarpon Ait) vines. The upper 3 rates significantly reduced breakdown during storage. Yields were increased by 500 and 1000 kg/ha, and berry weight by 1000 kg/ha. Berry volume, soluble solids, acidity, and anthocyanin content were not significantly affected. The 1000 kg/ha rate was optimum for yield and keeping quality.
Pecan Cultivars Differ in Leaf Elemental Concentration of Normal and Mouse-ear Leaf Tissue1
Authors: Worley Ray E.
Published: September 2022

Leaflet mineral concentration of normal and mouse-eared leaflets differed for different cultivars of pecan (Carya illinoensis (Wang.) K. Koch). Normal ‘Schley’ leaflets were higher in Mg, Cu, Cr and Pb than mouse-eared leaflets. Normal ‘Desirable’ leaflets were lower in Cr, Pb and Cd than mouse-eared leaflets. Normal ‘Mohawk’ leaflets were higher in Mn, Cu, Al, Cr, Pb, and Cd than mouse-eared leaflets. Normal ‘Wichita’ leaflets were lower in Ca, Mg, Zn, Cr and Pb than mouseeared leaflets. Normal ‘Mohawk’ leaflets had a higher Zn/Fe ratio and normal ‘Wichita’ had a lower Zn/Fe ratio than mouse-eared leaflets.
Reduction of Rootstock Sprouts on Young Grafted Avocados with NAA1
Authors: Boswell S. B. , Bergh B. O. , Whitsell R. H. , Kumamoto J.
Published: September 2022

Naphthaleneacetic acid (NAA) ethyl ester was applied as 0.5% aqueous spray 7 cm below the grafts of 9-month-old avocado (Persea Americana Mill.) prior to graft growth. No growth occurred on the grafts and plants were dead 4 months after treatment. Volatilization of ethyl ester of NAA applied as 0.3% to 1.0% aqueous spray, 7 cm below grafts that had grown out 12 cm, caused the new growth to wilt for 36 hours. The 0.4% spray caused slight bark burn of the seedling trunk. The higher the concentration the greater the burn. Sprays of 0.3 or 0.4% sodium salt NAA did not cause wilting or bark burn. Both formulations of 0.3 and 0.4% gave good control of sprouts on the seedlings trunks. The 0.3 and 0.4% ethyl ester treatments reduced total graft growth.
Enhancement of Peroxyacetyl Nitrate Injury to Petunia Foliage by Benomyl1
Authors: Pell E. J. , Gardner W.
Published: September 2022

The response of ‘White Cascade’ and ‘Coral Magic’ petunia (Petunia hybrida Vilm. -Andr.) plants to peroxyactyl nitrate (PAN) was tested 7 days after application of soil drenches of 0, 20, 40, 60, 80, 100, 120 μg benomyl/g drv weight of soil. The susceptible ‘White Cascade’, showed increased sensitivity to 745 μg/m3 PAN for 1.5 hr when soil was treated with benomyl levels of 60 μ/g soil or greater. Enhanced foilar response to PAN was similar at all concentrations of benomyl greater than 60 μ/g soil. Foliage of ‘White Cascade’ petunias treated with concentrations of benomyl below 60 μ/g soil, responded to PAN similarly to plants which were not treated with the fungicide. The PAN sensitivity of the tolerant ‘Coral Magic’ was unaffected by benomyl application.
Influence of Fertility and Moisture Level on Growth of Chlorophytum1
Authors: Hipp Billy W. , Colbaugh Phillip F. , DiLeo Mario
Published: September 2022

Increasing fertilizer rates resulted in increased stolon production, plantlet production, and total plant growth of Chlorophytum. Maximum number of stolons and optimum plant growth were obtained with solutions containing 2g/liter of 20-8.3-14.9 (N-P-K) fertilizer applied twice weekly. Frequent watering resulted in maximum growth at high fertilizer levels while less frequent watering resulted in maximum growth at lower fertilizer levels.
Evaluation of Bentazon for Yellow Nutsedge Control in Container-grown Nursery Stock1
Authors: Fretz Thomas A. , Sheppard Wendy J.
Published: September 2022

Postemergent applications of bentazon (3-isopropyl-1H-2, 1-3-benzothiadiazon-(4) 3H-one 2, 2 dioxide) at 0.84, 1.68, 3.36 and 6.72 kg ai/ha effectively controlled yellow nutsedge (Cyperus esculentus L.) in nursery containers but all rates severely injured container-grown woody ornamentals.
Concentrations of Carbon Dioxide and Ethylene in the Cavity of Attached Papaya Fruit1
Authors: Akamine Ernest K. , Goo Theodore
Published: September 2022

The patterns of concentrations of CO2 and C2H4 in the cavity of attached ripening papayas (Carcia papaya L. cv. Solo) were similar to those of CO2 in respiration and C2H4 production in detached ripening fruits. The peak concentrations of these gasses occurred when the surface color of the fruits was about 80%. The flavor of the pulp of the ripe fruit was rated highest at this time.
Branch Samples for Yield and Fruit Size Comparisons in Apple1
Authors: Forshey C. G. , Elfving D. C.
Published: September 2022

Differential fruit thinning treatments produced differences in yield, fruit numbers, and fruit size in 2 ‘McIntosh’ and 1 ‘Empire’ apple (Malus domestica Borkh.) orchards. Fruit set, crop load, and fruit size data calculated from branch samples paralleled corresponding data for whole trees.
Rapid Production of Small Fruiting Grapevines from Softwood Cuttings1
Authors: Robitaille H. A. , Janick Jules
Published: September 2022

Small fruiting plants of grape (Vitis sp.) were produced by rooting softwood cuttings after fruit set.
A “No Choice” Study for Evaluating Resistance of Apple Fruits to Four Insect Pests1
Authors: Goonewardene Hilary F. , Kwolek W. F. , Mouzin T. E. , Williams E. B.
Published: September 2022

“No choice” procedures were established to complement “free choice” procedures for determining resistance of apple fruit to 4 insect pests. ‘Starking Delicious’ was more resistant to damage by apple maggot, Rhagoletis pomonella (Walsh) than ‘Jonathan’ or ‘Golden Delicious’. There were no differences in damage to ‘Jonathan.’ ‘Golden Delicious’ and ‘Starking Delicious’ by plum curculio, Conotrachelus nenuphar (Herbst) or redbanded leafroller, Argyrotaenia velutinana (Walker). The resistance of some apple scab resistant selections to these insects and codling moth, Laspeyresia pomonella (L.) previously determined in a “free choice” test was confirmed in this “no choice” test.
Behavior of the Tomato Fruitworm, Heliothis zea (Boddie), on Susceptible and Resistant Lines of Processing Tomatoes1
Authors: Cosenza Gilson W. , Green Henry B.
Published: September 2022

Under field conditions, leaves of a breeding line of tomato (Lycopersicon esculentum Mill.) were less suitable for larval feeding of tomato fruitworm, Heliothis zea, than were the leaves of ‘Campbell-28’ and ‘Chico III’, although this did not influence the number of larvae arriving at the fruits. Significantly fewer larvae penetrated fruits of the breeding line than those of the cultivars, indicating that the principal source of resistance was in or near the fruit skin. The fruits of the breeding line exhibited a significant degree of antixenosis compared with the fruits of the cultivars when choice was given to the larvae between fruits under laboratory conditions.
Effects of Plant Density and Nitrogen Fertilizer on Sweet Corn1
Authors: Moss Joe D. , Mack H. J.
Published: September 2022

Total husked ear yield of sweet corn, Zea mays L. cv Jubilee, increased 38% as plant density was increased from 4.39 to 15.85 plants/m2. At populations above 10.98 plants/m2, marketable yields, based on ≥ 220 g ear size, were reduced. Plant height, weight of leaves, stalk diameter, and total plant weight were significantly affected by both plant density and nitrogen (N) rates. Nitrogen rates of 56, 112, and 224 kg/ha significantly increased ear weight over the 0 kg/ha rate but there were no significant plant density-N interactions.
Effect of Growth Regulators on Seed Germination of Archontophoenix alexandrae1
Authors: Nagao M. A. , Sakai W. S.
Published: September 2022

Seed germination of Alexandra palm [Archontophoenix alexandrae (F. J. Muell,) H. Wendl & Drude] was accelerated by presoaking for 24 or 72 hours in water, and further accelerated by a 72 hour treatment with 100 or 1000 ppm, gibberellic acid (GA), but not with benzyladenine (BA) or naphthaleneacetic acid (NAA).
Composted Hardwood Bark: A Substitute for Steam Sterilization and Fungicide Drenches for Control of Poinsettia Crown and Root Rot1
Authors: Daft G. C. , Poole H. A. , Hoitink H. A. J.
Published: September 2022

Rhizoctonia and Pythium crown and root rot of Euphorbia pulcherrima willd ex Kotzch cv. Annette Hegg Dark Red were suppressed in a composted hardwood bark medium amended with sphagnum peat. The suppression equalled that obtained in an aerated steam-treated peat medium drenched with fungicidies. Growth of ‘Annette Hegg Dark Red’ produced in the sphagnum peat-amended bark was improved over plants produced in a sterilized and fungicide drenched soil-peat-perlite medium. Addition of muck to composted hardwood bark negated the desirable growth effects.
Aluminum and Manganese Toxicity of Rose Plants Grown in East Texas1
Authors: Keisling T. C. , Fuqua M. C.
Published: September 2022

A field survey in 1977 and greenhouse studies revealed that chlorosis and stunting in rose (Rosa hybrida L. cv. Summer Snow) budded on Rosa multiflora Thumb. root-stock was due to Mn and A1 toxicity on soils with pH 5.0 or below. Liming reduced Mn and A1 tissue concentrations, promoted root growth, and alleviated chlorosis.
Silver Ion Increases Endogenous Ethylene in Sweet Potato Vine Cuttings1
Authors: Walker D. W. , Paterson D. R. , Earhart D. R.
Published: September 2022

Concentration of endogenous ethylene was higher in Ag+-treated cuttings of sweet potato (Ipomoea batatas Lam.) than in the control or in cuttings subjected to 48°C for 2 minutes. When leaf tissue was dipped in 0, 125, 250, or 500 mg/liter Ag+, endogenous ethylene was increased by the 250 and 500 mg/liter treatments. When equal concentrations of NO3– were applied to cuttings as KNO3, Ca(N)O3)2, or AgNO3, only AgNO3 increased the endogenous ethylene content.
Effects of Soil Applications of Magnesium Sulfate and Dolomitic Limestone on Pimiento Pepper1
Authors: Dempsey A. Hugh , Boswell Fred C.
Published: September 2022

Plant weight of pimiento pepper (Capsicum annum L. cv Truhart Perfection) was more closely related to soil K and Mn levels than soil Mg in a greenhouse study. Plant Mg levels were increased significantly by MgSO4 or dolomtic limestone additions. The sufficient-check soil produced significantly larger plants than the deficient-check or Mg-treated deficient soil.
Status of Harvest Mechanization of Fruits, Nuts, and Vegetables1
Authors: Zahara M. , Johnson S. S.
Published: September 2022

Mechanization has progressed further with crops for processing–38% of the fruits and 58% of the vegetables are machine harvested. For fresh market, over 90% of the nuts, 26% of the vegetables, and less than 1% of the fruits are harvested mechanically.
Some Nutritional and Metabolic Aspects of ‘Delicious’ Apple Trees with Dead Spur Disorder1,2
Authors: Klaren C. H. , Ketchie D. O.
Published: September 2022

In ‘Delicious’ apple (Malus domestica Borkh.) trees affected by dead spur disorder (DS) no over-all deficiency was in N, P, K, Ca, amino acids, proteins, sugars or phenols as compared with healthy (CK) trees. N, amino acid and protein contents were higher in DS than in CK spurs on 1- and 2-yearold limb sections. Relatively low nutrient levels in DS spurs on 3-4-year old limb sections indicated that translocation of nutrients to these spurs was restricted. Phenol contents were lower in DS than in CK spurs. P and K contents were higher in DS than in CK spur leaves.
Determining T50 of Peach Flower Buds with Exotherm Analysis1
Authors: Proebsting E. L. , Sakai Akira
Published: September 2022

There is need for rapid determination of cold resistance of plants in the field. Exotherm analysis was adapted to such needs for dormant fruit buds of peach (Prunus persica (L.) Batsch). Buds were excised with 1-2 mm of vascular tissue attached and then held near the thermocouple junction with an A1 foil wrap. Exotherms could be recorded from most of 25-30 buds per junction. Resolution was improved by slow rates of temperature decrease in the critical range (near l°/hour). At high rates of temperature decrease (8 to 15°/hour) buds were killed at higher temperatures. The distribution of bud mortality with temperature was very close to the standard skewed curve for buds evaluated by the tissue browning method.
In Vitro Propagation of Rose1
Authors: Hasegawa Paul M.
Published: September 2022

Cultured shoot tips and lateral buds from greenhouse-grown rose (Rosa hybrida L. cv. Improved Blaze) proliferated multiple shoots on a basal medium (MS salts, vitamins, glycine, sucrose, and agar) supplemented with 3.0 mg/liter 6-benzylamino purine (BA) and 0.3 mg/liter indoleacetic acid (IAA). A 3-fold multiplication was achieved from freshly explanted terminal shoot tips or lateral buds after 8 weeks. Reculture of in vitro-derived shoots onto the same medium resulted in a 6-fold increase in 8 weeks. Roots could be initiated from about 50% of these shoots after transfer to a medium containing 0.3 mg/liter IAA and 0 or 0.3 mg/liter BA. Regenerated plants were successfully transferred to soil after 2 weeks.
Promotion of Renewal Canes in Greenhouse Roses by 6-Benzylamino purine without Cutback1
Authors: Ohkawa K.
Published: September 2022

Growth promotion of lower axillary buds and the development of renewal canes, for rejuvenating greenhouse rose plants (Rosa hybrida L.) and increasing cut flower production without cutback, was induced by treating lower buds with 6-benzylamino purine (BA) in lanolin paste. These BA effects varied with cultivar, plant age, bud condition, top growth, time of treatment, and use of scoring.
Inheritance of Resistance to Gummy Stem Blight in Watermelon1
Authors: Norton Joseph D.
Published: September 2022

The inheritance of resistance to Didymella bryoniae (Auersw.) Rehm (= Mycosphaerella citrullina C. O. Smith) in watermelon (Citrullus lanatus (Thunb.) Matsum. & Nakai) plant introduction PI 189225 was determined in crosses with the susceptible cultivar ‘Charleston Gray’. Segregation of F2 and backcross populations indicated that resistance to D. bryoniae in PI 189225 is governed by a recessive gene.
‘Jessie M. Conner’ Gladiolus1
Authors: Wilfret Gary J. , Magie Robert O.
Published: September 2022

Gladiolus (G. hortulanus L. H. Bailey), when planted in landscapes, offer a variety of flower colors and shapes found in few cultivated plants. Unfortunately, use of gladiolus in the home landscape has diminished dramatically over the past 20 years. A major contributor to this decline has been the emphasis in breeding programs to develop exhibition flowers with long thin stems and numerous florets, qualities not desired in a landscape plant. When used in the home garden, the modern cultivars have to be staked and tied or they collapse and break during adverse weather conditions. Another factor in the decline of gladiolus has been the disease susceptibility to Fusarium (F oxysporum f. sp. gladioli Snyd. & Hans.) corm and root rot. Without fumigation of the soil and pre-plant and postharvest fungicide treatments of the corms, most cultivars will have only a maximum garden life of 2-3 years. A garden cultivar, in addition to disease tolerance, should possess a strong root system, a strong, straight spike, and a rachis with at least 14 florets. Plants should be vigorous, self-perpetuating, and easily propagated. ‘Jessie M. Conner’ (Fig. 1) possesses all of these qualities.
Comparative Photosynthesis and Transpiration in Excised Shoots of Rabbiteye Blueberry1
Authors: Teramura A. H. , Davies F. S. , Buchanan D. W.
Published: September 2022

Photosynthesis in rabbiteye blueberry (Vaccinium ashei Reade) was found to saturate at low irradiances and had a low light compensation level. In contrast to many other plants, both stomatal and residual diffusion resistance contributed equally to the total leaf diffusion to CO2. Relatively higher stomatal resistances in rabbiteye blueberry result in an efficient water-use, enabling it to withstand drought. No cultivar differences were found in photosynthesis, transpiration, or dark respiration to account for differences in yield.
Cultivar and Cultural Influences on the Establishment of Kentucky Bluegrass from Plugs1
Authors: Turgeon A. J. , Street J. R.
Published: September 2022

Rate of coverage from plugs of ‘A-20’ Kentucky bluegrass (Poa pratensis L.) planted in Flanagan silt loam and treated with oxadiazon at 3.4 kg/ha increased as mowing height increased from 1.9 to 3.8 to 7.5 cm and with fertilization at 25 kg N/ha per growing month or higher. Sod strength measurements taken 2 years after planting were highest in plots receiving 25 kg N/ha per growing month compared to 0, 50, and 100 kg. Where plugs of 48 cultivars of Kentucky bluegrss received the same oxadiazon treatment, phytotoxicity ranged from no injury to complete necrosis.
Sensitivity and Growth of Twelve Elatior Begonia Cultivars to Ozone1
Authors: Reinert R. A. , Nelson P. V.
Published: September 2022

Twelve cultivars of Elatior begonia (Begonia X hiemalis Fotsch.) were exposed to O3 at 25 and 50 pphm. The ‘Schwabenland’ group, ‘Whisper ‘O’ Pink’, and ‘Improved Krefeld Orange’ were the most sensitive, whereas ‘Ballerina’, ‘Mikkell Limelight’, and ‘Turo’ were the least sensitive. ‘Rennaisance’, ‘Heirloom’ ‘Nixe’, and ‘Fantasy’ were intermediate in sensitivity. The dry weight of foliage (stems plus leaves) of 9 cultivars exposed to O3 was significantly less than that of control plants. Ozone at 25 and 50 pphm inhibited flower growth (including peduncles) and development in 4 and 8 of the 12 cultivars, respectively. Differences in flower weight ranged from 43 to 105% of the control at 25 pphm and from 25 to 98% of the control at 50 pphm, depending on cultivar.
Macronutrient Stability during Overwintering of Royal Beauty Cotoneaster and Andorra Juniper1
Authors: Sheppard W. J. , Gilliam C. H. , Fretz T. A.
Published: September 2022

Fluctuations of macronutrient levels in the leaves, stems and roots were analyzed in Cotoneaster dammeri, C. K. Schneid, cv. Royal Beauty and Juniperus horizontalis, Moench cv. Piumosa during the overwintering period. Potassium, Mg and Ca levels, in both species, maintained periods of relative stability. Tissue P levels remained stable in all tissues, while Ν levels in leaves, stems and roots of both species fluctuated significantly throughout the sampling period.
Vegetative Maturity of Red-osier Dogwood and Response to Herbicides1
Authors: Crabtree Garvin , Fuchigami L. H.
Published: September 2022

Plants of red-osier dogwood (Cornus sericea L.) treated with 2,4-dichlorophenoxy-acetic acid (2,4-D) or l,1’-dimethyl-4,4’-bipyridium ion (paraquat) after reaching vegetative maturity were much less affected by the herbicides than plants treated earlier. Data support the hypothesis that vegetative maturity is a distinct physiological stage in the development of woody plants, and that inconsistencies in herbicide efficacy can, in part, be explained by this phenomenon.
Spotless Gold, Spotless Yellow, and Spotless Pink Rose: Blackspot Resistant Breeding Lines1
Authors: Semeniuk Peter
Published: September 2022

Here we report the first evidence of resistance of roses to the blackspot disease, Diplocarpon rosae Wolf. Black-spot is a major foliar disease of roses that causes severe losses to commercial and home gardeners. It spreads rapidly on susceptible cultivars, results in premature defoliation, and severely reduces yield and quality of this popular plant. Growers must make frequent applications of fungicides which are costly in labor and materials and environmentally undesirable. Stewart and Semeniuk (3) reported on the problems and techniques in transferring resistance to blackspot from the diploid species to garden roses (1, 2). The breeding lines Spotless Gold, Spotless Yellow, and Spotless Pink will be released for use as resistant parents in breeding programs. This germplasm should be valuable to breeders for its resistance to 7 isolates of D. rosae from Belts-ville, Maryland, Tifton, Georgia, Ames, Iowa, Ithaca, New York, Delaware, Ohio, University Park, Pennsylvania, and Tyler, Texas. These roses have been released by the U.S. Department of Agriculture, Science and Education Administration. The developmental work was done by the Florist and Nursery Crops Laboratory at the Agricultural Research Center, Beltsville, Maryland.
Lettuce Emergence from Vermiculite Seed Tablets Containing Activated Carbon and Phosphorus1
Authors: Sharpies G. C. , Gentry J. P.
Published: September 2022

Lettuce (Lactuca sativa L.) seedlings emerged from vermiculite tablets but did not survive in warm weather plantings (maximum daytime air temperature >32°C) under irrigated desert conditions. Final plant stands of 90% were obtained with modified seed tablets containing activated carbon and nutrient P in cool weather (maximum daytime air temperature <26°C).
Retention of Fruit Firmness and Increase in Vegetative Growth and Fruit Set of Apples with Aminoethoxyvinylglycine1
Authors: Williams Max W.
Published: September 2022

Aminoethoxyvinylglycine (AVG), an inhibitor of ethylene synthesis, applied to ‘Delicious’ apple trees (Malus domestica Borkh.) 2 weeks before harvest reduces loss of flesh firmness of apples in storage and increases vegetative growth in the following growth season. When applied to ‘Delicious’ or ‘Golden Delicious’ trees after full bloom, the “June drop” was completely eliminated; thus, fruit set was significantly increased.
Nitrogen Fertilization Increases Yield without Enhancing Blossom Receptivity in Almond1
Authors: Weinbaum S. A. , Uriu K. , Micke W. C. , Meith H. C.
Published: September 2022

Ground application of urea increased yields of ‘Nonpareil’ almond (Prunus amygdalus Batsch) by increasing the number of flowers per tree rather than by increasing blossom receptivity and percentage fruit-set. Hand pollination of flowers on caged limbs indicated that blossom receptivity declined between 3 and 6 days after anthesis.
Micropropagation of Rabbiteye Blueberries1
Authors: Lyrene P. M.
Published: September 2022

Multiple shoot formation from shoot tips taken from juvenile rabbiteye blueberry (Vaccinium ashei Reade) seedlings was induced on Knops medium with agar, casein hydrolysate, and N6-(∆2-isopenteny1)-adenine (2iP) at 15 mg/liter. These shoots could be easily subcultured and rooted readily when cut off and inserted into a peat-perlite mixture under mist in the greenhouse. Nonjuvenile shoot tips from rabbiteye cultivars were difficult to establish in cultures. Successful establishment of some clones occurred by formation of fine, filamentous shoots which were as amenable to subculture as juvenile shoots. A 50-fold multiplication rate every 4 months was obtained with some clones.
Symptoms of Acetaldehyde Injury on Head Lettuce1
Authors: Stewart Joseph K. , Aharoni Yair , Hartsell Preston L. , Young David K.
Published: September 2022

Acetaldehyde (Aa), a volatile produced in small quantities by plants, is a potential fumigant for killing the green peach aphid, Myzus periscae (Sulzer), on harvested head lettuce, (Lactuca sativa L. var. capitata). Concentrations of 3.0 to 6.0% Aa killed 100% of the green peach aphids on harvested head lettuce, but induced dark-green, water-soaked, necrotic areas on the outer leaves of the heads and occasionally caused a type of injury, similar to russet spotting, which we call tan flecking. Concentrations of 1.5 to 2.0% Aa, which killed all of the aphids, did not injure the lettuce.
Rooting of Young Root-shoots of Red Raspberry in Auxin Solutions1,2
Authors: Torre L. C. , Doss R. P. , Barritt B. H.
Published: September 2022

Root-shoots of red raspberry (Rubus idaeus L.) rooted in auxin solutions in 10 days. Root initiation was markedly influenced by auxin concentration.
Ion-selective Electrode Determination of Calcium in Apple Fruits1
Authors: Himelrick David G. , Ingle Morris
Published: September 2022

A rapid method for estimating total Ca of apple (Malus domestica Borkh.) peel and flesh was developed using a Ca-selective electrode to measure ionic juice Ca++. Ionic juice Ca++ ranged from 3.2 to 7.2 ppm. Significant correlations were found between total Ca and ionic juice Ca++ for flesh (r = 0.91) and peel (r = 0.87).
The Effect of Drastic Reduction of Water Input on Mature Walnut Trees1
Authors: Martin G. C. , Uriu K. , Nishijima C.
Published: September 2022

Withholding irrigation of walnut trees (Juglans regia L. cv. Ashley) for one growing season significantly reduced trunk growth and kernel weight. Tree survival and return cropping were unaffected. When irrigation was resumed kernel weight was significantly heavier than that from trees irrigated the previous year.
Effect of Dikegulac on Pecan Shuck Dehiscence and Number of Spring Shoots1
Authors: Worley Ray E.
Published: September 2022

Dikegulac, when applied in the fall of a dry year, did not enhance shuck dehiscence of pecan (Carya illinoensis (Wang.) K. Koch but did promote increased numbers of new shoots on young trees the next spring.
Influence of Medium pH on Growth of ‘Roosevelt’ Ferns1
Authors: Hipp Billy W. , Morgan David
Published: September 2022

In greenhouse studies, maximum growth of Nephrolepis exaltata (L.) Schott ‘Rooseveltii’ was obtained in an acid (pH 4-5) medium. Dry weight of ferns decreased as pH of the medium increased.
G.A.-13 Avocado Rootstock Selection1
Authors: Kadman A. , Ben-Ya’acov A.
Published: September 2022

‘G.A.-13’ avocado (Persea americana Mill.) was selected to provide a rootstock for saline and lime conditions.
Colorado Horticulture
Authors: Knutson Kenneth W.
Published: September 2022

Horticulture in Colorado is diverse from the standpoint of types of plants grown and even more so in terms of climate. Topographic elevation ranges from slightly over 3000 feet in the eastern high plains to over 14,000 feet in the Rocky Mountains (50 peaks exceed this elevation!). The frost-free growing season varies from 16 days in certain high mountain valleys to 192 days in the fruit growing areas in western Colorado. However, a common factor in all areas, regardless of altitude, is the need for irrigation water — Colorado is a semi-arid state in which precipitation varies from less than 8 to slightly over 16 inches.
Modification of Plant Architecture and Crop Yield by Breeding1
Authors: Coyne Dermot P.
Published: September 2022

Plant breeders have modified plant architecture to fit crop production systems, particularly for mechanical harvesting, but have given inadequate attention to the effects of architecture on yield. The development of high yielding dwarf wheat, rice and determinate tomato cultivars have emphasized the relation of plant architecture to crop yield. Delayed flowering of photoperiod sensitive dry beans (Phaseolus vulgaris L.) under long days produced more fruiting nodes per plant and increased yield 50 to 70%. The contributions of plant architecture components to yield and quality have been investigated with near-isogenic lines of various crops. Modifications of plant architecture have been adopted to alleviate heat and moisture stress, to confer insect resistance, and to avoid disease.
Induction of Staminate Flowers on Gynoecious Cucumber by Aminoethoxyvinylglycine1
Authors: Owens K. W. , Tolla G. E. , Peterson C. E.
Published: September 2022

Aminoethoxyvinylglycine (AVG) at 50,100, and 200 ppm induced staminate flowers on 3 gynoecious cucumber lines in the greenhouse. Both the time of application and the type of water used to prepare the AVG solutions had a significant effect on the node at which conversion from pistillate to staminate first occurred and on the total number of nodes bearing staminate flowers. Plants treated with 100 and 200 ppm AVG were chlorotic for about 10 days after application.
Increased Yield of the Cultivated Mushroom in Israel by Artificial Misting1
Authors: Bashan Yoav , Platt Mark
Published: September 2022

Artificial misting before the first flush, and between all the flushes increased yield of Agaricus bitorquis (Quelet) by 33% and up to 75% in A. bisporus (Lange).
Ethephon as Harvest-aid for Muscadine Grapes1
Authors: Phatak S. C. , Austin M. E. , Mason J. S.
Published: September 2022

(2-Chloroethyl)phosphonic acid (ethephon) was applied at 0, 570, 1000 and 2000 ppm to muscadine grapes (Vitis rotundifolia Mich. cv. Hunt), 1, 2, or 3 days before once-over harvest. All ethephon treatments increased berry abscission and reduced skin tear due to harvest when berries were harvested 2 days or 3 days after spraying. Delaying harvest to 3 days after treatment with 2000 ppm ethephon increased berry abscission to 46% and reduced skin tear to 9% in 1977. In 1978, 2000 ppm of ethephon increased berry abscission to 29% and reduced skin rupture to 29%. Taste panels could not detect flavor difference from the ethephon treatments.
Breeding Strawberries for Resistance to the Aphids Chaetosiphon fragaefolii and C. thomasi1
Authors: Barritt Bruce H. , Shanks Carl H.
Published: September 2022

Segregation for resistance to the strawberry aphids, Chaetosiphon fragaefolii (Cockerell) and C. thomasi (Hille Ris Lambers), occurred in the first backcross from the resistant ‘Del Norte’ clone of Fragaria chiloensis (L.). Aphid populations on ‘Del Norte’ were 4 and 7% of those found on the susceptible cultivar ‘Totem’ in greenhouse and field evaluations respectively. Resistance of the most resistant backcross seedlings was comparable to that of the F1 parent but slightly less than ‘Del Norte’. Greenhouse and field evaluations gave generally similar results although field evaluations have greater practical significance.
Legume Cover Crops, Organic Mulch and Associated Soil Conditions, and Plant Nutrient Content for Establishing Quillou Coffee1
Authors: Oladokun Michael A. O.
Published: September 2022

Four cover crops, calopogonium (Calopogonium mucunoides Desv.), centrosema (Centrosema pubescens Benth.), pueraria (Pueraria phaseoloides (Roxb.) Benth.) and cowpea, (Vigna unguiculata Walp) and 2 types of organic mulch, grass and banana/plantain leaves were used in comparison with clean weeding as control in establishing Quillou coffee (Coffea canephora Pierre var canephora Haarer). Shade significantly affected the plant N, P, and K percent nutrient content but nonsignificant on Mg, Ca, and Na. Cover crop and mulch treatment effects were significant only with P and K while interactions between shade and these treatments were nonsignificant for any of the nutrients considered. Percent soil moisture content was influenced by both shade and treatments as well as their interactions in both June and January. Soil pH was significantly affected by both shade and other treatments in January but no significance was recorded in June.
Quality and Yield of ‘Keauhou’ Macadamia Nuts from Mixed and Pure Block Plantings1
Authors: Ito P. J. , Hamilton R. A.
Published: September 2022

Annual yields of ‘Keauhou’ macadamia (Macadamia integrifolia Maiden & Betche) from a mixed planting averaged about 16 kg per tree more than from a pure block planting. The nuts from mixed-orchard nuts as compared to pure block stands were large (2.72 vs. 2.39 g), had more kernels (38 vs. 35%) and more oil (80.0 vs. 75.7% no. 1 nuts, those > 72% oil).
Use of Metal Compounds as Root Pruning Agents1
Authors: Pellett Harold , Litzow Margaret , Mainquist Laurie
Published: September 2022

Several metal salts were effective in killing root tips of squash, lima bean, and Kentucky coffeetree seedlings without damaging the rest of the plant in greenhouse trials. Silver nitrate was effective in promoting root branching of woody plant seedlings in a field trial.
Thatch Accumulation in Kentucky Bluegrass as Influenced by Cultivar, Mowing, and Nitrogen1
Authors: Shearman R. C. , Kinbacher E. J. , Riordan T. P. , Steinegger D. H.
Published: September 2022

Twenty-one Kentucky bluegrass (Poa pratensis L.) cultivais differed significantly in their thatching tendency during 4 years of study. ‘Glade’, ‘Cheri’, and ‘Victa’ accumulated the most thatch, while ‘S-21’, ‘A-34’, and ‘Park’ accumulated the least. Increasing mowing heights from 2.5 cm to 5.0 cm significantly increased the tendency to accumulate thatch. Increasing nitrogen nutritional levels from 10 g m−2 to 20 g m−2 did not increase thatching tendency.
Evaluation of Drip Irrigation for Container Production of Woody Landscape Plants1
Authors: Weatherspoon D. M. , Harrell C. C.
Published: September 2022

Average efficiency of drip systems (amount of water retained by container expressed as water supplied) over 2 years ranged from 44-72% as compared to 13-20% for overhead sprinklers. Chapin Leader Tubes and Micro-drippers and Spot System Vortex Emitters performed better and required less maintenance than Chapin Twin-wall hose or DuPont Viaflo tubing.
Overwintering Container-grown Ornamentals under Thermo-blankets with and without Clear, White, or Black Polyethylene1
Authors: Gouin F. R.
Published: September 2022

Early spring flowering of Forsythia × intermedia Zab. (forsythia) and growth of Cydonia sinensis Thouin (Chinese quince) can be prevented by over-wintering container grown plants under microfoam thermo-blankets covered with black, white, or clear polyethylene (poly) spray painted in late winter and diluted white latex paint. Although covering microfoam with black poly may extend its useful life and suppress the growth of winter weeds, it appears damaging to X Cupressocyparis leylandii A. J. Jacks & Dallin. (Leyland cypress) and Prunus laurocerasus L. (cherry laurel). Ilex crenata Thunb. (Japanese holly), Viburnum rhytidophyllum Hemsl. (leathe leaf viburnum) and Euonymous alata Thunb. ‘Compacta’ (dwarf winged euony-mus) responded equally well to all treatments. Thermo-blankets protected the roots from minimum killing temperatures but highest maximum temperatures were measured under polyethylene foam and microfoam covered with clear or woven clear polyethylene.
Freezing Resistance of Perennial Turfgrasses1
Authors: Gusta L. V. , Butler J. D. , Rajashekar C. , Burke M. J.
Published: September 2022

The cold hardiness of 6 cool season grass genera was compared in mid-winter under controlled freezing conditions. Creeping bentgrasses (Agrostis palustris Huds.) tolerated the lowest temperatures whereas perennial ryegrasses (Lolium perenne L.) was the least hardy. Kentucky bluegrass (Poa pratensis L.) readily loses cold hardiness when exposed to warm conditions and did not reharden when exposed to cool temperatures. Appreciable hardiness in Kentucky bluegrass was induced by simulating drought conditions.
Effects of Excess Manganese Nutrition on the Growth of Easter Lily1
Authors: Holmes R. L. , Coorts G. D.
Published: September 2022

Six levels of Mn were applied in nutrient solution to ‘Ace’ and ‘Nellie White’ Easter lilies (Lilium longiflorum Thunb.) grown to anthesis. ‘Nellie White’ Mn tissue content was higher than ‘Ace’. Foliar symptoms of Mn toxicity did not appear at or below solution applications of 50 ppm Mn. High levels of Mn resulted in shorter plants, lower plant dry weight, leaf chlorosis and chlorotic mottling, and some leaf curling.
Factors Influencing the Culture and Propagation of Xerophytic Succulent Species1
Authors: Stefanis James P. , Langhans Robert W.
Published: September 2022

Media, nutrition, light and temperature studies were conducted with several species of Cactaceae and Crassulaceae to develop systems for propagating and growing succulents from seed or cuttings in the cool climates and low light irradiances found at northern latitudes. A peat-perlite (1:1 by volume) medium was suitable for rooting and growth. Nitrate nitrogen applied at the rate of 100 ppm with every watering appears optimal for various species at all stages of propagation and development. Most species grew equally well when grown at 10° or 17ºC night temperature. Acceptable germination percentages were obtained with an irradiance of 220 µE·m−2s−1 and a medium temperature of 24°C.
In Vitro Propagation of Anthurium andreanum Lind.1
Authors: Kunisaki J. T.
Published: September 2022

High yields of viable cultures of Anthurium andreanum were obtained with the use of small explants of vegetative buds and a long disinfestation soak. Explants were grown into plantlets in modified Murashige and Skoog medium supplemented with 15% coconut water (by volume). For clonal increase, best results were obtained when stem sections from asepti-cally grown plantlets were cultured in medium containing 6-benzylamino purine (BA) at 0.2 mg/liter. There was no further increase in number of shoots at higher BA concentrations but callus growth increased and shoots were stunted.
Association of Calcium in Chilling Injury Susceptibility of Stored Avocados1
Authors: Chaplin Grantley R. , Scott K. J.
Published: September 2022

Visible injury in chilled avocados (Persea americana Mill.) was observed first in the distal end of fruit. The proximal end remained apparently unaffected unless exposure to chilling temperature was prolonged. In contrast, the concentration of endogenous Ca of individual fruit was always highest in the proximal end and lowest in the distal end. Severity of visible injury in stored fruit was significantly reduced when Ca was applied to harvested fruit by vacuum infiltration of CaCI2·
Classification of Hawaiian Avocado Cultivars According to Flower Types1
Authors: Ito P. J. , Fujiyama D. K.
Published: September 2022

Seventeen of 47 avocado cultivais grown in Hawaii were classified as class A and 30 as class B flowering types.
‘Santa’, ‘Gem State’, and ‘Benewah’ Tomatoes1
Authors: Boe A. A. , Pelofske P. J. , Bakken T. J.
Published: September 2022

‘Santa’, ‘Gem State’, and ‘Benewah’ tomatoes {Ly copersicon esculentum Mill.) are 3 new “ultra early” cultivars. ‘Santa’ and ‘Benawah’ resemble the “Sub Arties” (1) whereas ‘Gem State’ is a dwarf patio type similar to ‘Pixie’.
Effects of Naphthaleneacetic Acid on Fruit Size, Quality, and Ripening of ‘Zahdi’ Datepalm1
Authors: Mohammed Shafaat , Shabana Hassan R.
Published: September 2022

Preharvest application of naphthaleneacetic acid (NAA) at 10, 20, 40, and 60 ppm concentrations to immature ‘Zahdi’ date palm (Phoenix dactylifera L.) fruit 15 to 16 weeks after pollination (late chimri stage) influenced fruit size, quality, and ripening. Compared with the controls, 40 and 60 ppm NAA treatments increased fruit size, weight, volume, pulp to seed ratio, and moisture content At 60 ppm fruit weight was increased by 39%. Total soluble solids were not altered significantly. Fruit ripening was delayed at least one month by 40 and 60 ppm.
Somatic Embryogenesis in Cell Cultures of Carica stipulata1
Authors: Litz Richard E. , Conover Robert A.
Published: September 2022

Somatic embryogenesis was induced in cell suspension cultures of callus derived from peduncle explants of Carica stipulata Badillo. The presence of activated charcoal stimulated embryogenesis particularly when BA and NAA were both in the growth medium. Plantlets derived from embryos have been successfully transferred to potting mixture.
Partial Organogenesis in Tissue Cultures of Averrhoa carambola1
Authors: Litz Richard E. , Conover Robert A.
Published: September 2022

Callus was initiated from seedling leaf explants and from leaves of recent vegetative flushes of mature Averrhoa carambola L. trees on solid Murashige and Skoog medium with added growth regulators. Seedling-derived callus demonstrated a strong dependence on the presence of exogenous cytokinin, 1-5 mg/liter 6(γ, γ-dimethylallylamino) purine (2iP) with 0.2 mg/liter 2,4-dichlorophenoxyacetic acid (2,4-D), for induction and growth. Shoot differentiation was stimulated from seedling callus by increasing the concentration of available cytokinin. Callus induction and growth from young leaves of mature trees was auxin-dependent (2-5 mg/liter 2,4-D with 0.5 mg/liter 2iP. Organogenesis from callus cultures of mature leaf origin was not obtained.
In Vitro Propagation of Hosta sieboldiana1
Authors: Meyer Martin M.
Published: September 2022

Plants were initiated from florets of Hosta sieboldiana (Lodd.) Engler cultivars cultured on a modified Murashige-Skoog medium containing 0.5 – 2.5 mg/liter naphthaleneacetic acid (NAA) and 0.5 – 2.5 mg/liter 6-benzylamino purine (BA) and grown in the light. These plants could be separated and proliferated on a similar medium to give large numbers of plants. Plant propagated from ‘Frances Williams’ had a chimeral separation into green and gold sports as well as retaining the chimeral organization.
Influence of Fertilizer and Lime Rates on Nutrient Concentration in Highbush Blueberry Fruit1
Authors: Cummings George A. , Lilly J. P.
Published: September 2022

Concentrations of N, P, K, Ca, Mg, Mn, Fe, Zn and Cu in blueberry fruit (Vaccinium corymbosum L. cv. Wolcott) as influenced by 3 rates of N, P, and K and 2 rates of lime were determined for 2-4 years. Concentration varied among years, but the variation was much less for N, P, K, and Ca than for Mg and the micronutrients. Application of N, P, or K increased the concentration of the element applied. Application of lime did not influence elemental concentrations. Increasing N rates decreased fruit Ca, and P decreased Mn concentrations each year.
Effect of Silver Thiosulfate and Preservative Solutions on the Vase Life of Miniature Carnations1
Authors: Reid Michael S. , Farnham Delbert S. , McEnroe Ellen P.
Published: September 2022

Short-term or over-night pretreatment with solutions of a silver thiosulfate complex extended the vase life of fresh or stored miniature carnations (Dianthus caryophyllus L.) as much as the continuous use of commercial vase preservatives. Combining the 2 treatments further extended the vase life to 4 times that of control flowers. The time to wilting of the first flower was closely correlated with the mean vase life of all the flowers in a spray.
The Effect of Cumulative Photosynthetically Active Radiation on the Growth and Flowering of the Seedling Geranium, Pelargonium × hortorum Bailey1
Authors: Lee Erickson Virginia , Armitage A. , Carlson W. H. , Miranda R. M.
Published: September 2022

Growth and flowering of Pelargonium × hortorum Bailey cvs. Sprinter Scarlet, Sprinter White, and Ringo were associated with cumulative photosynthetically active radiation (PAR); 41-65% of the variability in days to flower was attributed to cumulative PAR. Vegetative and total plant height decreased as cumulative PAR increased. The number of lateral breaks increased as irradiance increased while fresh weight showed no consistent pattern.