bluuebunny/crossref_metadata_2025 huggingface dataset:
EFFECT OF BARE GROUND, ALL GRASS, OR ALL BROADLEAF GROUND COVERS ON BIOLOGICAL MITE CONTROL AND ON TREE GROWTH AND PRODUCTIVITY
Authors: Coli William M.
Published: April 2024

As a component of a large, interdisciplinary study of Biointensive Integrated Pest Management, the composition of orchard ground covers and woody borders was characterized in 28 Massachusetts commercial apple orchards, and plants which were most likely to harbor Tetranychid spider mites and Phytoseiid mite predators was determined. Data are presented on makeup of plant communities within orchards and adjacent woody borders. All species of spider mites and mite predators were more often observed on broadleaf plants than on grasses.

In 1989, two 1-Acre orchard blocks were established to compare the effect of of either bare ground, an all grass row, or an all broadleaf row ground cover on phytophagous and predatory mite population dynamics, and on tree growth and productivity. Data are presented on frequency of occurrence of mites found in timed scans, and on differences in trunk circumference increase in each ground cover regime.
LOW DOSE γ-IRRADIATION AND MODIFIED ATMOSPHERE PACKAGING EFFECTS ON QUALITY AND MICROFLORA CHANGES IN BLACKBERRIES
Authors: Barth M.M. , Langlois B.E. , Christenson R. C.
Published: April 2024

Increased interest has been demonstrated in the production and marketing of thornless blackberries. Once blackberries are harvested, the length of time they can be stored at low temperatures above freezing is limited by initiation of fungal spoilage and rapid loss of market quality. The objective of this study was to assess effects of low dose γ-irradiation and modified atmosphere packaging on market quality retention of thornless blackberries as evaluated by Hunter color values, Instron shear rates, TSS, pH, and microbial growth over 96 h. Blackberries were irradiated at ambient temperatures using a Nordion Gammacell Model 220 (dose rate =11.0 Grays/min) delivering a 0.3 kGy dose to the tissue. Both control and irradiated samples were placed in packaged and nonpackaged groups, stored over 96 h (4°C), taken for analysis at 24 hr intervals. An additional treatment included packaged controls containing C2H4 absorbant. Following 72 h storage, packaged samples were stored in air to determine subsequent benefit. CO2 and O2 concentrations inside packages were 7.5% and 11.6%. By 72 hr, yeast and mold counts were lower in irradiated, packaged samples, but a significant increase was observed following placement of samples in air.
TOLERANCE OF STRAWBERRIES TO LOW O2 AND/OR HIGH CO2 ATMOSPHERES
Authors: Kader Adel A.
Published: April 2024

Controlled atmospheres (CA) with low O2 and/or high CO2 concentrations are effective in maintaining quality and extending the postharvest life of strawberries. The efficacy of CA in controlling decay and insects (to meet quarantine requirements) requires O2 levels below 1% and/or CO2 levels above 15%. The tolerance of strawberries to such fungicidal and/or insecticidal CA depends upon the cultivar, temperature, and duration of exposure. Development of alcoholic off-flavor is the main detrimental effect of low O2 and/or high CO2 stresses and is associated with accumulation of ethanol and ethyl acetate due to increased activities of alcohol dehydrogenase and acetyl CoA alcohol transferase. Strawberries tolerate exposure at 0 or 5°C to 0.5 or 0.25% O2 (balance N2) for 10 days, air + 20% CO2 for 10 days, or air + 50% or 80% CO2 for 6 days before alcoholic fermentation and other injury symptoms become objectionable. Keeping strawberries in non-injurious CA has positive residual effects on their flesh firmness, color, and composition after transfer to air.
OLIVE FRUIT LOOSENING WITH PHOSPHORUS
Authors: Martin George C. , Nishijima Chic
Published: April 2024

Under laboratory conditions foliar sprays of NaH2PO4 to olive explants induce fruit loosening with low percent leaf loss. In the field, NaH2PO4 foliar sprays are less successful in fruit loosening. Trunk injections of NaH2PO4 to olive trees in the field result in both leaf and fruit abscission. The lack of fruit abscission inducement from foliar sprays is thought to be due to poor chemical penetration. To improve penetration of NaH2PO4 several additives were tested to slow drying rate. These treatments led to increased fruit abscission over that of NaH2PO4 used without an additive. Even more fruit abscission was achieved with H3PO4 but this treatment led to fruit marking. Several additives were mixed with H3PO4 in addition to pH adjustment to ameliorate the fruit marking problem. The best current treatment combines H3PO4 with adjuvants such as Regulaid or Activator 90. It appears that adjuvant reduction of surface tension results in H3PO4 spread over more fruit surface, inducing less fruit making, while retaining the fruit abscission inducement feature desired.
ASPECTS OF POLLINATION IN HYLOCEREUS, A CACTUS NEWLY INTRODUCED TO THE NEGEV DESERT OF ISRAEL
Authors: Weiss Julia , Nerd Avinoam , Mizrahi Yosef
Published: April 2024

Hylocereus is a night-flowering cactus, whose hermaphrodite flowers reach a diameter of 22 cm. It was found in early studies that both self-fertility and self-sterility occur among the 14 species introduced to Israel. Flowers of all species behaved similarly concerning the phenology of flower opening and closing. Flowers opened about 1 hr. before sunset and were completely closed at approximately 6 hrs. after sunrise. Handcross-pollination led to 100% fruit set until 24 hrs. after flower opening, after which time both stigma receptivity and pollen germinability declined. Crossings between species bearing red fruits led to a higher fruit weight (424±134 g) in comparison to crossings between red-fruited species and species with yellow spiny fruits (146±64 g). Pollen germination in vitro for red-fruited species ranged from 23 to 59% but was only 0.7% for yellow-fruited species. To test the effectiveness of the honey bee as a pollinator a beehive was placed inside a nethouse. The flowers were visited by bees mainly in the morning; the bees foraged on pollen and eventually touched the stigmata of the flowers. Both the regularity of bee visits and the percentage of fruit set after bee visitation was very low (19%). This might be due to the fact that flowers were not constantly available; therefore the bees did not accept them as a constant and reliable pollen source.
EXPRESSION OF THE GUS GENE IN AGROBACTERIUM TUMEFACIENS-TRANSFORMED SPINACH PLANTS
Authors: Al-Khayri J.M. , Miles R.W. , Huang F.H. , Morelock T.E. , Stewart J.McD.
Published: April 2024

Transgenic spinach (Spinacia oleracea L., cv. High Pack) plants were regenerated from callus derived from hypocotyl segments. Explants were cocultivated for 48 h with Agrobacterium tumefaciens harboring pMON 9749 plasmid conferring kanamycin resistance and β-glucuronidase (GUS) activity. To induce callus, the explants were cultured on Murashige and Skoog (MS) selective medium containing 2 mg L-1 kinetin and 0.5 mg L-1 2,4-D. Shoots developed from the callus upon transfer to selective regeneration medium supplemented with 2 mg L-1 kinetin, 0.01 mg L-1 2,4-D, and 1 mg L-1 GA3. Shoots were rooted on MS medium containing 1 mg L-1 IBA. Excluding the cocultivation medium, all others were supplemented with 50 mg L-1 kanamycin, 100 mg L-1 cefotaxime, and 100 mg L-1 carbenicillin. To confirm transformation, kanamycin-resistant callus and leaf sections from regenerants were assayed for GUS activity using the X-gluc assay. Stable GUS gene expression in transgenic plants was demonstrated. This is the first report of regenerating transformed spinach.
DIRECT SOMATIC EMBRYOGENESIS FROM PROTOPLASTS DERIVED FROM EMBRYOGENIC SUSPENSION CULTURES OF ASPARAGUS OFFICINALIS L.
Authors: May Roger A. , Sink Kenneth C.
Published: April 2024

Embryogenic callus from four asparagus genotypes (JG8, MD10, MD22, and 86SOM1) was initiated from micropropagated spears placed on semisolid LS medium containing 5 μM 2,4-D or 50 μM NAA, concomitantly. After three subcultures such cells were used to initiate suspensions in liquid medium of the same composition. The eight sets of suspensions were used as sources of protoplasts at two months of age and again at five months. Protoplasts were immobilized at 105/ml density in MS medium with 0.6% agarose and overlaid with liquid KM medium containing the auxin of the corresponding donor suspension or no hormones. Plating efficiencies were recorded at 14 days and ranged from 0% to 40% depending on the genotype, suspension medium, and inclusion or exclusion of hormones in the protoplast plating medium. All four genotypes were capable of forming somatic embryos directly from protoplasts; however, conversion was greatest from MD10 and MD22 derived cultures and occurred as rapidly as six weeks after initial protoplast culture.
LANDSCAPING THE DESERT OF KUWAIT
Authors: Abdal Mahdi S. , Albahouh Mohamed S.
Published: April 2024

The Climate of Kuwait is characterized by hot and dry summers with frequent sandstorms, and mild winters with low rainfall. Soils are generally sandy in texture. Water supplies are particularly limited and all ground water resources are extremely brackish with an average total dissolved solids (TDS) content of 4500 mg/l. Trickle system is the major method used for irrigation. Lack of water is the main limiting factor in Kuwait. High temperature is another factor causing increased evaporation. Such evaporation brings soluble salt to the soil surface and forms saline soils. Salinity is further elevated by the use of brackish water in irrigation. There have been many ways to alleviate this problem, but the most important approach practiced has been to carefully select plant species that are saline and heat tolerant. Tests have been carried out to establish the tolerance of numerous species, under conditions of brackish (3500-4500 mg/l) water irrigation and high temperatures. Lists of some of the plant species found to be most tolerant will be presented. Some of these plant species are already native to Kuwait and are adapted to local conditions, while others need to be acclimatized.
GEL POLYMER CAN REDUCE LEACHING AND IMPROVE NUTRITION OF STRAWBERRY PLANTS
Authors: Whitworth Julia , Roberts Warren
Published: April 2024

An experiment was performed using `SuperSorb-C' polyacrylamide copolymer (gel) to determine whether the gel decreased leaching of nitrate, potassium, or phosphorus. The treatments were: gel polymer alone, gel polymer with fertilizer added, sand alone, sand with fertilizer added, gel polymer and sand, and fertilized gel with fertilized sand. One hundred ml of water was added to the pots every three days. This was done twelve times. Twenty-four hours after the water was added, the leach was removed from dishes beneath the pots. The leach was analyzed for nitrate, potassium, and phosphate content. Nutrient leaching was greater in sand than in gel or sand amended with gel. In other experiments, strawberry plants were grown in various combinations of sand, gel and fertilizer in 15 cm pots in the greenhouse. The plants were analyzed for nutrient content. Nitrogen and phosphorous content of plant tissue was increased when gel was mixed with the sand. Results of these experiments will be presented.
SEASONAL NITROGEN ACCUMULATION BY MATURE `CONCORD' GRAPEVINES
Authors: Hanson Eric J. , Howell G.S.
Published: April 2024

Mature vigorous `Concord' grapevines (Vitus labruscana, `Bailey) at Clarksville, MI, were excavated at two to five week intervals from 29 April (bud break) until 28 September. Vines were separated into roots, wood (trunks and cordons), new shoots and leaves, and fruit. Tissues were weighed, then analyzed for total N to determine how much N vines accumulated annually, and when absorption occurred. Vines contained 18 g N at bud break, 75 g at fruit maturity, and 43 g when leaves were becoming senescent in late September. At fruit maturity when vine N content was highest, the new shoots and leaves, fruit, roots, and wood contained 53, 28, 11 and 8% of vine N, respectively. Vines absorbed N most rapidly between late May and early July, when the most rapid vegetative growth occurred.
THE EFFECT OF PRUNING LEVEL, SOIL-APPLIED NITROGEN, AND FOLIAR NUTRIENT APPLICATIONS ON GROWTH, YIELD, AND FRUIT QUALITY OF `CONCORD' GRAPEVINES
Authors: Kamas James S. , Dunst R. M. , Pool R. M.
Published: April 2024

The effects of three levels of pruning severity, two rates of soil applied nitrogen, and a three spray regime of foliar nutrients were investigated at a commercial `Concord' vineyard during the 1991 and 1992 growing seasons. While increased node number resulted in higher yields of less mature fruit, yield, vigor and fruit maturity were unaffected by rate of soil applied nitrogen. In both years, while yield was significantly reduced by the application of foliar nutrients growth and fruit maturity was unaffected.
LABOR-SAVING, HORIZONTAL SYSTEM FOR GREENHOUSE TOMATO PRODUCTION
Authors: Green James L.
Published: April 2024

Four determinant tomato varieties were evaluated for salinity tolerance (0-4500 ppm added salinity), blossom-end rot susceptibility (0 or 50% ammonium nitrogen), and yield in the closed, insulated pallet system (CIPS). Growth and yield of the four tomato varieties in CIPS was greater than that of the controls in a surface-irrigated, open container production system.

Single-harvest, horizontal greenhouse tomato production in the CIPS, when compared with the conventional vertical system, has advantages: 1) Less labor is required with the determinant (non-trellised)parthenocarpic (nonpollinated), concentrated bloom-maturity, single-harvest tomato varieties. After transplanting into the CIPS, no additional water or fertilizer or handling are required during the production period. 2) Production per given production area is equal or greater. In CIPS plant density was four-times greater. 3) Supplementary lighting is more efficient.
HORTICULTURAL CONSULTING--A NATIONAL AND INTERNATIONAL PERSPECTIVE
Authors: Albrigo L. Gene
Published: April 2024

There is a wide spectrum of consulting opportunities available for many horticulturists who wish to pursue them. These range from full-time career consulting to the part-time endeavor typical for many academics and retirees. Consultants are employed by individual producers, commodity groups, governments, international agencies or university groups (as in departmental review processes and international programs). These activities will be discussed primarily in relation to academic responsibilities along with guidelines, procedures and policies one typically encounters when undertaking consulting.
HORTICULTURAL PROGRAMS OF USAID--CONTRACTS AND CONSULTANTS
Authors: Hortik Harvey J.
Published: April 2024

The United States has maintained a strong commitment to international development in agriculture, including horticulture, through various programs directed primarily by USAID. The development and execution of many of the programs are contracted to private US companies and universities. These contractors hires consultants, using some guidelines from AID. Situations where USAID hires consultants directly and the criteria used will be discussed also.
CROP DEMAND INCREASES POTASSIUM UPTAKE BY MATURE PRUNE TREES
Authors: Weinbaum S.A. , Niederholzer F.J.A. , Ponchner S. , Rosecrance R.C. , Carlson R.M. , Whittlesey A.C. , Muraoka T.T.
Published: April 2024

Two heavily-cropping, twelve-year-old prune trees (Prunus domestica L., syn. `Prune d'Agen') were compared with two adjacent trees which were defruited during stage II of fruit growth (28 May). Trees were uprooted, dissected, and processed to determine total nonstructural carbohydrates, tree nutrient contents and within-tree distribution at the time of fruit maturity (28 July). Trees defruited 2 months earlier contained 5 times as much starch and 2.5 times as much total nonstructural carbohydrates (TNC) in leaves and perennial tree parts as did cropping trees at the time of fruit maturity.

Cropping trees absorbed about 90 g more K during stage III of fruit growth than did defruited trees during the same interval (28 May -28 July). Vegetative trees parts (i.e., trunk, branches, roots, and leaves) in cropping trees generally had lower K contents than did defruited trees at the time of fruit maturity. Fruit demand for K was associated with increased K uptake from the soil despite reduced levels of TNC in the roots and the probability of reduced root growth. Potassium uptake by heavily cropping trees was not resource limited when K was supplied regularly through the drip irrigation system.
INHERITANCE OF TOMATO FRUIT CAROTENOID CONTENT IN POPULATIONS DERIVED FROM A CROSS OF LYCOPERSICON ESCULENTUM × L. CHEESMANII
Authors: Stommel John R.
Published: April 2024

Tomato fruit carotenoid content was measured in mature fruit of parental, F1, F2 and backcross populations derived from an initial cross of L. esculentum, cv. Floradade, with the orange fruited L. cheesmanii, LA 317. Segregation patterns for orange flesh color and percent β-carotene in F1, F2 and backcross populations fit expected models for a single dominant gene conditioning a high percentage β-carotene content and resultant orange fruit pigmentation. The inheritance of β-carotene in L. cheesmanii paralleled that of the B gene described in L. hirsutum. β-carotene was generally accumulated at the expense of lycopene in orange-fleshed individuals. Correlations between carotenoid type and total carotenoid content were not evident. Variation observed in segregating F2 and backcross populations for total carotenoid content suggested that gains in selection for increased β-carotene and lycopene content may be realized.
DIURNAL CHANGES IN NITRATE CONCENTRATION IN POTATO LEAVES
Authors: McLaskey Steven E. , Minotti Peter , Halseth Don
Published: April 2024

The purpose of this project was to determine what, if any, are the diurnal changes in nitrate concentration in potato leaves. In dried petioles there was a decrease in nitrate, on most days, from early morning to the middle of the day. The pattern of the change was found to be influenced to some extent by weather conditions, and some differences in average nitrate levels were found on different days. Nitrate in fresh sap was measured with a nitrate specific ion electrode and two quick tests. Nitrate in fresh petiole sap was found to have a different diurnal pattern than nitrate in dried petioles. That is, there was usually an increase in nitrate-N from early morning to the middle of the day, although the change was sometimes not significant. The nitrate concentration of the fresh sap was found to be sensitive to the water status of the plants and decreased after a heavy rain. In most cases the difference in nitrate concentration between plots receiving 83 kg N/ha and plots receiving 165 kg N/ha was greater than the diurnal change.
INTERNAL CARBON DIOXIDE AND ETHYLENE LEVELS IN TOMATO FRUIT RIPENING ATTACHED TO OR DETACHED FROM THE PLANT
Authors: Saltveit Mikal E.
Published: April 2024

The internal concentration of CO2 and C2H4 and the stage of ripeness was periodically measured in tomato fruit (Lycopersicon esculentum cv. Castelmart) attached to and detached from the plant. An external collection apparatus permitted nondestructive sampling of internal gases. The concentration of CO2 and C2H4 in the collection apparatus had equilibrated with the internal gas concentrations after 18 hr. A 20-fold increase in C2H4 during ripening of detached tomato fruit was paralleled by a 3-fold increase in CO2 concentration. Ripening attached fruit exhibited a 100-fold rise in C2H4 during ripening, but lacked a ripening associated climacteric rise in O02. CO2 did increase 2-fold in an erratic fashion during ripening of attached fruit, but the increase did not show any correspondence to increased C2H4 or ripening associated color changes. In tomato fruit, it appears that a CO2 climacteric per se, which has been considered an intrinsic quality of certain ripening fruit, may not be necessary for the ripening of “climacteric” fruit at all, but may instead be an artifact of using harvested fruit.
THE EFFECTS OF MODIFIED ATMOSPHERE PACKAGING AND TEMPERATUR ON POSTHARVEST STORAGE LIFE OF HOT PEPPERS (Capsicum frutescens L.)
Authors: Mohammed Majeed , Wilson L.A. , Gomes P.I.
Published: April 2024

Two cultivars of hot peppers were stored under various O2 and CO2 regimes generated using modified atmosphere packaging techniques at 5°, 10°, 20° and 30°C. Hot peppers treated with a bactericide and packaged in microperforated high density polyethylene (HDPE) bags stored best at 10°C with the level of decay-free fruits at 96.1% after 25 days. Incipient chilling injury (CI) without visible symptoms after short storage periods at 5°C was detected both by reduced bioelectrical resistance, and increased electrolyte leakage. The severity of CI progressed more rapidly when fruits, sealed in micro-perforated HDPE bags and stored for 30 days at 5°C were transferred to 28-30°C for 1, 3, or 5 days respectively. The detrimental effects of increasing CO2 and C2H4 concentrations within packages particularly upon transfer to elevated temperatures contributed to the severity of the symptoms.
PRINCIPLES OF MODELING CROP GROWTH AND DEVELOPMENT, MODEL TYPES, TECHNIQUES, AND SIMULATION
Authors: Kobayashi Kent D.
Published: April 2024

Crop modeling encompasses the use of mathematics, statistics, and equations to describe quantitatively crop growth and development. It can be useful tool to describe, quantify, and predict crop growth, development, and phenology. Crop models fall into two general classes—statistical (empirical) or mechanistic (physiological)—or they may be a combination of the two. The model type depends upon several factors including the objectives of the modeler, understanding of underlying physiological processes, and availability of data. Model development proceeds from a preliminary conceptual model through formalization into a mathematical model. Models are later verified, and validated, if possible. Model development is an iterative process with continual refinement as more data becomes available and understanding increases. Simulations are dynamic models that follow the growth and development of crops over time. They are more mechanistic in nature and involve changes in measurable quantities of the crop as affected by changes in rates of physiological processes.
MODELING PHOTOSYNTHESIS AND CARBON PARTITIONING IN ROW CROPS
Authors: Boote K. J. , Pickering N. B.
Published: April 2024

Many horticultural crops are grown in rows rather than in horizontally-uniform stands. Thus it is important to be able to model light interception and photosynthesis of incomplete hedgerow crops. In our model, absorption of direct and diffuse irradiance by incomplete hedgerow canopies is computed as a function of canopy height, width, leaf area index (LAI), leaf angle, row direction, latitude, day of year, and time of day. A sunlit versus shaded LAI approach is used to compute absorption of photon flux density (PFD) by sunlit versus shaded leaves. Canopy assimilation is the sum of sunlit and shaded leaf rates over their respective LAI classes. Photosynthesis of sunlit and shaded leaves is computed with the asymptotic exponential equation, with quantum efficiency and light-saturated rate terms being made sensitive to intercellular CO2 (Ci), O2, and temperature. Farquhar and van Cammerer equations are used to compute the efficiency of electron conversion to CO2 fixation. Stomatal conductance depends on leaf rate and Ci to Ca ratio. Examples of canopy assimilation response to PFD, CO2, temperature, and LAI will be illustrated for incomplete canopies, with and without canopy energy balance.
USE OF SOMATIC EMBRYOS AS SYNTHETIC SEEDS FOR REDUCING MICROPROPAGATION COSTS
Authors: Gray Dennis , Compton M.
Published: April 2024

Somatic embryogenesis is the most efficient method of clonal propagation that can be envisioned. Somatic embryos engineered to be of practical use in plant production are termed “synthetic seeds”. Mature somatic embryos possess pre-formed shoot and root meristems and can be induced to germinate with minimal manipulations. Over 2,000 somatic embryos have been recovered per gram of culture material. Therefore, many plants can be produced with little manipulation when compared to conventional micropropagation. Perhaps the most immediate application of synthetic seed technology exists for crops with high per plant values that are already propagated by tissue or organ culture, such as many ornamental species. Propagation of these crops is labor-intensive. Integration of simple synthetic seed systems would dramatically reduce labor requirements, thus lowering production costs. Furthermore, substitution of synthetic seed technology for tissue and organ culture technology in the commercial micropropagation industry would allow a wider variety of crop types to be economically produced.
INTRODUCTION TO COLLOQUIUM ON INTELLECTUAL PROPERTY RIGHTS: PROTECTION OF PLANT MATERIALS
Authors: Stoner Allan K.
Published: April 2024

Historically, intellectual property protection for plants has been viewed differently than for other forms of technology; however, in recent years several factors have led to an increased motivation to protect plant materials. This, in turn, has resulted in many questions and concerns for scientists, administrators, and policy makers regarding options available for protection; impact of protection on research agendas and germplasm exchange; and ethical and social considerations. A workshop on Intellectual Property Rights: Protection of Plant Materials was held in Washington, DC, on January 26-28, 1993. This meeting was to provide invited participants the latest information on the protection of plant-derived intellectual property via patents and other means. It was also intended to review and develop policies and procedures that are publicly responsible; yet, provide incentives to assure commercialization of new inventions. The organizers and attendees agreed that a record of the workshop would be published and that special efforts should be made to communicate the results of discussions to the membership of scientific societies such as ASHS.
INTERNATIONAL GERMPLASM COOPERATION - CONCERNS, FUTURE
Authors: Shands Henry L.
Published: April 2024

International plant germplasm cooperation has been strongly based upon scientist to scientist cooperation in the past, most often from academic relationships. Exchanges of germplasm between scientists has been common. In the more formal system, public institutions have relied upon bilateral and multilateral government programs and upon efforts of cooperation with International Agricultural Research Centers of the CGIAR. All of these cooperation efforts have involved access to genetic resources. The IBPGR, in its new structure, the International Plant Genetic Resources Institute, will be little involved in germplasm exchanges. UNEP's Convention on Biological Diversity has legal language, when in force, may greatly affect access to genetic resources directly and though international centers even though the objective is to make them more readily available. Public sector institutions in the United States will have greater difficulty than private seed industry firms in arranging access when a cost is negotiated but perhaps easier access when training and other cooperation is acceptable. Some possible activities of cooperation in the future to gain access are discussed.
MATRICONDITIONING AND DRYING OF SUPERSWEET CORN TO IMPROVE STAND ESTABLISHMENT
Authors: Khan Anwar A. , Ptasznik Wlodzimierz , Prusinski Janusz
Published: April 2024

Effects of preplant conditioning of supersweet corn (`GSS 3368' and `Challenger') seeds and subsequent drying on the quality and performance of seeds were studied. Matriconditioning with moist Micro-Cel E (MC) was superior to matriconditioning with moist Vermiculite #5 and Celite 400 or osmoconditioning with -1.2MPa polyethylene glycol solution at 15°C. A ld conditioning (seed: carrier: water= 5:1:7) of `GS 3368' and `Challenger' sweet corn with MC improved the seed quality, as shown by reduced electrolyte leakage; reduced the time to 50% of final emergence at 10/20°C (12/12h) in a peat-lite mix by 1 to 2d; and increased the shoot wt by 70-90%, 10 to 12d after planting. Various drying protocols were used to reduce the high water content (49% w.b.) in the ld conditioned `Challenger' seed to 14% (w.b.). At 25°C and 30% RH, conditioned seeds needed 24h to dry to 14% water content at an air flow velocity of 0.02m/s and only 7.5h at 1.4m/s. At 35°C and 30% RH, the time of drying was reduced to 16 and 5h at 0.02m/s and 1.4m/s air velocities, respectively. At 45°C and 30% RH, seeds were dried within 5h at 0.02m/s air velocity and within 3.5h at 1.4m/s. Benefits to seeds acquired through conditioning was retained maximally by drying at 35°C, 30% RH and 1.4 m/s air velocity.
EFFECT OF POLYETHYLENE MULCH COLOR ON THE FRUITING RESPONSE OF STRAWBERRY
Authors: Albregts Earl E. , Chandler C. K.
Published: April 2024

Eight colors of polyethylene mulch were evaluated in the strawberry (Fragaria × ananassa, Duch.) production field. Fruit production by March 1 was increased during 3 seasons by yellow and 2 seasons by white colored mulches compared to the black mulch. Average fruit weight, number of fruit per plant, and percent marketable fruit affected fruit yield depending on the season. Total fruit yield was reduced with some of the colored mulches during two seasons. The soil temperature of the plant beds was warmest throughout the season with the black mulched beds and coldest with the white and yellow mulched beds.
CROP CORRELATION AND CALIBRATION OF MEHLICH-1 SOIL TEST EXTRACTANT FOR VEGETABLES
Authors: Hochmuth George , Hanlon Ed , Hochmuth Bob , Kidder Jerry , Hensel Dale
Published: April 2024

The Mehlich-l (double-acid) soil test extractant is used widely on sandy soils in the southeastern United States. Research with eight major vegetables in Florida showed that the Mehlich-1 solution for phosphorus was correlated with crop yield and quality responses. Soils with a Mehlich-1 index for phosphorus greater than 30 mg·kg-1 required no phosphorus fertilization. Crop responses were not highly correlated with Mehlich-1 potassium index and it was difficult to predict crop response to potassium fertilization. The lack of predictive capability of the Mehlich-1 extractant for potassium raises questions over soil testing for potassium on sandy soils in Florida where potassium is mobile.
SHIFTING PLANT NUTRITION PARADIGMS
Authors: Geraldson C. M.
Published: April 2024

The gradient concept as a shift in nutritional paradigms is designed to establish and stabilize a nutritionally optimal ionic composition in the soil solution and thus, the potential to provide nutritional accountability. This is accomplished by synchronizing the nutrient/water input with removal. The basic components are a constant water table with a constant but separate source of N-K from the soil bed surface, all of which is protected by a full bed mulch. By shifting to the gradient-mulch system, Florida tomato growers more than doubled their yields and increased profitability by 40 to 60%. Conventional research efforts such as irrigation and fertilizer scheduling become irrelevant, along with measures of evapotranspiration and tensiometers; soil testing and plant tissue analyses can be de-emphasized and the many statistically designed experiments to evaluate nutrient levels have an outmoded nutritional validity. The shift of the gradient technology to a containerized concept has a maximum potential in the development of a globally sustainable production system. The failure to utilize these innovative paradigms limits the potential of nutritional research to advance beyond a level of mediocrity.
LIGHT AND NITROGEN LEVELS AFFECT THE AGRONOMIC PERFORMANCE OF VEGETABLE AMARANTH
Authors: Makus D. J.
Published: April 2024

Three-week-old transplants of Amaranthus tricolor cultivars `RRC 241' and `Hinn Choy' were given split applications of supplemental N (0, 100 and 200 kg/ha). Five weeks after sowing both cvs. were exposed to 100, 70 and 50% of ambient solar radiation for nine and ten days, respectively. During shading, avg. daily photosynthetic irradiance was reduced from 11.6 to 7.7 and 5.0 KW/m2, respectively. Soil, air, and leaf temperatures were reduced by shading. Plants were harvested in the seventh week. Cultivars differed in leaf number and area, yield, height, mineral uptake, and stem fresh and dry weight. Increasing shade levels decreased the dry wt. of stems, leaf blades, and plants. Shading had no effect on leaf area, plant fresh wt. or yield, but increased stem length, plant water content and leaf blade pigments. Photosynthetic fixation rates were reduced by 50% shade. Leaf blade protein and most leaf blade mineral nutrients, including nitrates, were increased by shading. Nitrogen application increased stem length, stem, leaf blade and plant fresh and dry wt., leaf blade pigments and yield.
PIGEONPEA: A POTENTIAL NEW CROP FOR VIRGINIA
Authors: Bhardwaj H. L. , Rangappa M. , Mohamed A. I. , Phatak S. C.
Published: April 2024

Six experimental pigeonpea (Cajanus cajan (L.) Millsp.) lines were evaluated during 1992 for their agronomic performance at Petersburg, Virginia under the New Crop Development Program of Virginia State University. The germination and stand establishment of indeterminate lines was poor due to low seed quality. The final seed yield varied from 349 to 2042 kg/ha with determinate types yielding significantly higher than indeterminate types. The experimental line GA#2 produced the highest yield. The protein content in mature seeds, harvested 175 days after planting (DAP), varied from 17.0 to 18.5 percent whereas the oil content varied from 1.7 to 2.3 percent. The seed yield was positively correlated with harvest index, seeds/pod, and seed weight. At 130 DAP, the 3 determinate lines yielded more than 10 metric tons of green beans per hectare (70 percent moisture). The protein and oil content of immature seeds from these pods varied from 18.1 to 21.2 and 2.1 to 2.2 percent, respectively. Pigeonpea, depending upon the variety, can also be used as an ornamental or vegetable plant in home gardens. The results of these experiments were quite encouraging.
INITIATING A STATE-WIDE HOME COMPOSTING PROGRAM
Authors: MCLAURIN W.J. , WADE G.L.
Published: April 2024

Sites in 12 locations throughout the state of Georgia were selected by the Department of Community Affairs. Each site contained up to eight types of composting bins and offered a self-guided tour with the appropriate signage at each of twelve stops.

The authors conducted meetings at 10 of the 12 sites. Using handouts, slide sets, videos, posters, hands-on demonstrations, and lectures, the demonstration team gave presentations designed to inform selected participants concerning the amount of home-generated compostable waste that currently goes into the landfills and the simple, “fail-safe”procedures they could use at home to turn this waste into an effective mulch/soil amendment for their yards and gardens.

Each participant received an information packet and a copy of The Home Composting Handbook, edited by the authors. During the meeting the demonstration team discussed composting structures, ways to build a backyard compost pile, and methods of maintaining the pile. Participants watched the actual building of a compost pile on site with materials typically found in local yards and gardens. Also, the demonstration team offered participants information on ways to involve the community and individuals within the community in implementation of home composting.
MASTER GARDENERS' PERCEPTIONS OF ADEQUACY OF TRAINING IN PESTICIDE USE AND ORGANIC GARDENING
Authors: Lerner B. Rosie , Dana Michael N. , Gann Ralph , Gibb Timothy , Shaner Greg , Whitford Fred , Kemery Ricky
Published: April 2024

Indiana Master Gardeners were surveyed to determine their perceptions of adequacy of training related to pesticide use in the home garden and landscape. Respondents were also asked to indicate their attitudes regarding “organic” gardening practices and education. Of the 1054 surveys mailed, 568 were returned with usable responses. Of these responses, 217 had received some advanced training. More than 75% of respondents felt that their MG training was at least adequate in the areas of problem diagnosis, pesticide selection & use, and pesticide safety. MG training in non-conventional pest control methods was deemed inadequate by 43%. Organic gardening information and techniques were described as at least somewhat important by 92% of the respondents. Organic gardening methods are always practiced by 10%, usually practiced by 49%. MG training in organic gardening was described as thorough by 10% of the respondents, adequate by 47%, inadequate by 30%. No training was received in this area by 12%. Responses often varied with age, gender, and educational and training background of the respondent.
PRE-GERMINATION TREATMENTS INFLUENCE GERMINATION AND PLANT SURVIVAL OF YUCCA GLAUCA GERMINATED ON LS MEDIUM
Authors: Brott Jody J. , Read Paul E.
Published: April 2024

Seeds from three phenotypes of Yucca glauca were germinated using two pre-germination treatments for each phenotype. Treatments were: a 10% NaOCl (10 NaOCl) soak for 15 minutes and a 50% NaOCl (50 NaOCl) soak for 24 hours. Seeds were then placed on Linsmaier-Skoog (LS) medium in darkness for two weeks at 27-28 C. All radicles were emerging through the seed coats at the end of 50 NaOCl as compared to no visual difference in the seed appearance after 10 NaOCl. At the end of the two incubation periods, seeds from 50 NaOCl exhibited shoot development and elongation while seeds from 10 NaOCl exhibited little or no shoot development or elongation. Seeds from 10 NaOCl exhibited contamination and/or “bleeding” (phenolic exudates) within 4 weeks. All seedlings were transferred to fresh LS medium and cultured for 6, 12 and 18 weeks. Seedlings that received the 50 NaOCl developed fibrous roots at 8-10 weeks and the beginnings of a tap root at 16-20 weeks. Ten seedlings from 50 NaOCl were transplanted 9 months after germination.
IMPROVED EMERGENCE OF SOLANUM TORVUM BY SEED TREATMENT
Authors: Miura H. , Yoshida M. , Yamasaki A.
Published: April 2024

Several soilborne diseases severely affect eggplants (Solanum melongena L.) in Japan. Therefore, eggplants are usually grafted on rootstocks of various species resistant to these diseases. For the control of verticillium wilt (Verticillium dahliae Klebahn), Solanum torvum `Torvum vigor' plants are used for rootstocks. However since the seeds started to emerge after 12 - 14 days at 25C and only 40% of them emerged after 30 days, it was difficult to obtain seedlings of uniform size.

In this experiment, matric priming treatment of seeds prior to planting was modified to improve the emergence of the seeds of `Torvum vigor'. Vermiculite powder was selected as the substrate to control the water potential of seeds during the treatment. First, samples of 0.25g seeds (235seeds on an average) were mixed with various amounts of vermiculite powder and water at 25C in the dark during 1 week. Thereafter, the treated seeds were planted in soil and incubated at 25C under a 12h daylength regime and the emergence and growth were monitored. Second, the temperature for the treatment, growth regulators added to water, air pressure and components, and the duration of the treatment were varied. Finally, the optimum treatment for improving the emergence of Solanum torvum seeds was developed.
SEED TREATMENT EFFECTS ON VOLATILE ALDEHYDE PRODUCTION IN GERMINATING sh2 SWEET CORN.
Authors: Paine Thomas E. , Bennett Mark A.
Published: April 2024

Seeds of two shrunken-2 (sh2) sweet corn (Zea mays L.) cultivars, `Crisp'n Sweet 710' and `Camelot', were used to relate volatile production to seed quality and seedling establishment. The five seed treatments evaluated were a hydration and drying cycle, a biological control of Pythium, a hydration and drying cycle followed by a biological control, a fungicide treatment, and an untreated check. For the aldehyde assays, 50 seeds were germinated in a flask for 24 h with a test tube of a 3-methyl-2-benzo-thiazolinone hydrazone (MBTH) solution. One ml of the solution was then reacted with FeCl3, diluted with acetone, and absorbance read at 635 nm. A field study was run under cool soil conditions (10-16°C) for seedling emergence and growth. Aldehyde production from the seeds did not correlate with field results for seed treatments, but did show a distinct difference between cultivars. The biological control with the hydration and drying cycle significantly reduced aldehyde production. This may contribute to the effectiveness of biological treatments since Pythium spores can be stimulated by volatile compounds released from germinating seeds.
EFFECT OF CELL SIZE ON THE GROWTH OF BROCCOLI AND CABBAGE TRANSPLANTS IN THE TOBACCO FLOAT SYSTEM
Authors: Niedziela Carl E. , Gumbi Phumulani
Published: April 2024

Two studies each were conducted with Brassica oleracea L. Italica Group `Packman' and B. o. Capitata Group `Greencup' cabbage. Seed was germinated and grown in a commercial soilless media contained in polystyrene flats floating on a nutrient solution from commercial fertilizers. The solution macronutrient concentrations (mM) were 6.4 NO3, 4.3 NH4, 0.5 H2P04, 2.1 K, 2 Mg, and 2 S04. The solution micronutrient concentrations (μM) were 6.8 Fe, 4.7 B03, 3.4 Mn, 0.42 Cu, 0.30 Zn, and 0.008 MoO4. Three cell sizes were used: 15 cm3 (253 cells/tray), 26 cm3 (200 cells/tray), and 36 cm3 (128 cells/tray). Each cell had a depth of 6.5 cm. There were no differences in the mean plant height or weight of broccoli due to cell size in either experiment. There were also no differences in mean plant height of cabbage in either experiment. However, mean plant weight was heavier in the 36 cm3 (5.4 g) cell size than the 15 cm3 (3.4 g) cell size in the first experiment and heavier in the 36 cm3 (3.9 g) and 26 cm3 (3.4 g) cell sizes than the 15 cm3 (2.8 g) cell size in the second experiment.
ION ACCUMULATION IN PERICARP AND ENDOCARP OF CUCUMBER FRUIT AS INFLUENCED BY XYLEM AND PHLOEM IMPORT
Authors: Widders Irvin E.
Published: April 2024

Ion concentrations in pericarp tissue, 3.2% K+, 0.9% Ca2+, 0.57% Cl- 550 ppm NO3--N, 0.51% PO43--P and 1.2% SO42--S on a dry wt basis, differed from that in endocarp tissue, 4.1%, 0.3%, 0.46%, 96 ppm, 0.72% and 1.3%, respectively, in 5 cm diam. cucumber fruit. Controlled environment experiments tested the hypothesis that xylem and phloem differentially supply pericarp and endocarp tissues with nutrients. Application of 6 mM Ca (NO3)2 during fruit development resulted in the pericarp having higher contents of Ca2+ and NO3- but not the endocarp. Shade (50% full sunlight) caused Cl- and NO3- contents to decrease in both tissue. It was determined that xylem import could account for 73% and 100% of the total Ca2+ in pericarp and endocarp, respectively, but only approximately 19% and 8% of the K+. The role of xylem and phloem in supplying nutrients to developing cucumber fruits, as related to differences in transport of various ions within these two vascular systems, will be discussed.
SUITABILITY OF BLUEGRASS RESIDUES AS AN AMENDMENT IN CONTAINER MEDIA.
Authors: Tripepi Robert R. , Manning Leslie K. , Campbell Alton G.
Published: April 2024

Disposal of plant residues from bluegrass seed production is a potential problem tor the grass seed industry, yet the residues may be useful as an organic amendment in container mixes. Postharvest residues of Poapratensis L. `South Dakota' were composted alone, tub ground and composted, mixed with amendments (cattle manure [M] or alfalfa seed screenings [AS]) and composted, or left alone (raw). All residues were ground to 4 to 6 mm segments and mixed with peat moss and perlite (2:1:1 by volume). Selected chemical properties and growth of tomato seedlings (Lycopersicon esculentum Mill. `Laura') in the media were measured. Cation exchange capacity of the composted residue + AS medium was 50% greater than that of any other media, but electrical conductivity of this medium was also double that of all other media. Tomato seedlings grown in composted residue + AS medium had at least 3.5- and 4-fold more shoot dry weight and leaf area, respectively, than plants grown in other media. In addition, seedlings grown in composted residue + AS medium had 34 and 41% more shoot dry weight and leaf area than plants grown in 75% peat moss/25% perlite medium. Composted residue amended with AS appeared to be suitable as a peat moss extender in container media.
MANGANESE CRITICAL LEVELS FOR EARLY SWEETPOTATO GROWTH.
Authors: Mortley D. G.
Published: April 2024

The effects of 0.25, 1.0, 2.5, 10, and 100 mg/liter of Mn on sweetpotato [Ipomoea batatas (L.) Lam.] were evaluated in 1990 and 1991 by use the nutrient film technique (NFT). A modified half strength Hoagland solution with MnCl2 as the Mn source was used. Foliage and storage root dry weights declined linearly with increasing Mn concentration in whole plants, the decline occurring when Mn concentration approached 1000 ug/g. Storage root growth was severely restricted when Mn concentration in fibrous root reached 200 ug/g while foliage dry weight showed a more moderate decrease. Mn concentration was higher in the foliage than in fibrous roots. Roots of plants showed browning at higher (10 or 100 mg/liter) Mn concentrations in solution, which was stained blue with benzidine and bleached with oxalic-sulfuric acid solution, indicating the presence of oxidized Mn. Characteristic toxicity symptoms were observed in plants receiving 2.5, (moderate) 10 or 100 mg/liter Mn in solution. These results suggest that a Mn concentration of approximately 1000 ug/g in whole plants and 100 ug/g in fibrous roots are critical concentrations with respect to Mn toxicity in sweetpotato.
INFLUENCE OF POULTRY LITTER ON TOMATO YIELD, NUTRITION, AND SOIL CHEMISTRY
Authors: Baker M. L. , Earhart D. R. , Haby V. A.
Published: April 2024

Composted poultry litter (PL) containing 2.98% N was hand-applied on individual plots in a RCB design with 3 replications. Rates (0, 8.2, and 16.3 Mg·ha-1) were based on N content of the PL and requirement for maximum tomato production. Comparisons were made with a fertilizer blend (FB) containing 558 kg·ha-1 of 14.1N-5.7P-9.2K applied in split application. `Summer Flavor 5000' tomato plants were hand-planted 46 cm apart in rows spaced 3 m apart. Plant volume and average fruit weight were not influenced by any treatment. A 5920 kg·ha-1 yield increase was noted when PL rate was increased from 0 to 8.2 Mg·ha-1. Total yield was further increased 2757 kg·ha-1 by doubling the PL rate. Yields due to FB were lower but not significantly when compared to PL rates. This decrease in yield could possibly be attributed to FB lowering soil pH to borderline levels for production (5.7) while litter rates had little effect on pH. No differences in leaf P and K were measured. Both rates of PL decreased leaf Ca but increased Mg as rate increased. There was no difference in leaf N, P, K, Ca, or Mg when zero PL and FB were compared. FB increased soil NO3-N in the 0- to 30-cm depth zone more than the PL treatments. When comparing the highest PL rate to the lowest, there was almost a one and one-half time increase in residual soil K at the 0- to 15-cm soil depth. PL increased soluble salts only in the 0- to 15-cm soil depth, however, levels were low.