bluuebunny/crossref_metadata_2025 huggingface dataset:
664 A Breeders Perspective Using Molecular Techniques for Improving Fruit Quality
Authors: Scott J.W.
Published: February 2019

Plant breeders would welcome new tools to improve selection efficiency for complex traits such as improved flavor, especially since this is only one of many complex traits that a breeder has to integrate into improved cultivars. Using tomato (Lycopersicon esculentum Mill.) flavor as an example, a major obstacle to improvement is the lack of measurable traits to select for. It has been suggested that improved flavor can be achieved by increasing the soluble solids and acidity. Both of these traits are not simply inherited, but if fruit sampling is adequate, they can be measured and selected. Studies have located several molecular markers linked to high soluble solids, but some are also linked to undesirable traits such as small fruit size or low yield. Thus, the molecular markers are not being used in breeding programs at this point. Moreover, other studies have shown that flavor is also influenced by an array of aromatic volatiles. The importance of some of the volatiles has been reported, but the volatile profile that consistently results in superior tomato flavor is still not known. Molecular manipulation of a biochemical pathway has been done to increase the concentration of one volatile with positive results. However, this manipulation does not solve the overall flavor improvement problem. Furthermore, environment plays a profound role in tomato flavor, and this aspect needs to be dealt with if a branded high-quality product is to be successfully marketed. There are also flavor issues related to fruit firmness, pedicel type, and plant habit. In summary, molecular techniques may be useful in providing some incremental improvements for complex traits like tomato flavor, but more knowledge about targets to manipulate is required. There does not appear to be any cheap or easy solutions. If molecular approaches are to be commercially successful, they will have to be tied closely to a breeding program dedicated to the same goal.
666 Lychee Production and Postharvest Technologies in China
Authors: Chen Weixin
Published: February 2019

Lychee is a well-known subtropical fruit, much appreciated for its attractive red peel and excellent taste, but the fruit is very prone to postharvest peel browning and decay. China is the world leader in both acreage and yield of lychee production. Extensive research has been conducted to extend the fruit quality and shelf life. The talk presents a general review of the current research on postharvest physiology and shelf life preservation technologies of lychee in China.
670 Development and Current Situation of the Flower Industry in China
Authors: Zhao Liang-jun
Published: February 2019

Technological achievements of the flower industry since 1978 in China are summarized into six sections, which include 1) main ornamental plant gemplasm resources and its utilization; 2) introduction, improvement and propagation of new cultivars; 3) flower seed industry. The development trends and problems of the flower industry are also analyzed, especially in the flower seed industry.
682 New Perspectives on the Influence of Mid-season Environment on Apple Fruit Characteristics
Authors: Tustin D.S. , Fulton T. , Brown H.
Published: February 2019

Growth of apple fruit can be described as an initial exponential phase lasting the 40+ days of fruit cell division followed by a more-or-less linear phase where growth is by cell expansion. Temperature is a major influence on fruit growth rate during the cell division phase, thereby affecting fruit size at maturity. However it is generally thought that temperature has less-direct impact on fruit development during the fruit expansion phase. Our observations of apple growth among regions and seasons of considerable climatic variability led us to speculate that temperature may impact directly on fruit development during fruit expansion but that responses may be interactive with carbon balance (crop load) influences. Controlled environment studies are being used to examine this hypothesis. Potted `Royal Gala' trees set to three levels of crop (one fruit per 250, 500, or 1000 cm2 leaf area) were grown from 56 to 112 DAFB in day/night temperature regimes of 18/6, 24/12, and 30/18 °C. All trees grew in field conditions prior to and following the controlled environment treatments. Treatments were harvested when 20% to 25% of fruit on trees showed the visual indicators used commercially to indicate harvest maturity. Fruit were evaluated using attributes that determine quality and that may have implications for fruit post harvest behaviour. Temperature and crop load influences on time to maturity, fruit fresh and dry weight, fruit DM content, fruit firmness, fruit airspace content and estimated fruit cortical cell size will be presented and implications discussed.
683 Contributions of Early Season Environment and Crop Load to Apple Fruit Development
Authors: Stanley C.J. , Tustin D.S.
Published: February 2019

Many factors contribute to final apple fruit size. Researchers have studied these factors and have developed models, some very complex. Results from many New Zealand regions over several years suggest that early season temperature along with crop load are the key factors driving final fruit size. Accumulated growing degree days from full bloom to 50 days after full bloom (DAFB), accounted for 90% of the variance in fruit weight of `Royal Gala' apples at 50 DAFB under nonlimiting low-crop-load conditions. In turn, fruit weight at 50 DAFB accounted for 90% of the variance in final fruit size at harvest under the low-crop-load conditions. We hypothesise that a potential maximum fruit size is set by 50 DAFB, determined by total fruit cell number, resulting from a temperature-responsive cell division phase. Under conditions of no limitations after the cell division phase, we suggest that all cells would expand to their optimum size to provide the maximum fruit size achievable for that cell number. Factors which affect growth partitioning among fruits, e.g., higher crop loads, would reduce final fruit size, for any given cell number, when grown in the same environment. In Oct. 1999, four different crop loads were established at full bloom on `Royal Gala' trees (M9 rootstock) in four climatically different regions. In Hawkes Bay, similar crop loads were established at 50 DAFB on additional trees. Hourly temperatures were recorded over the season. Fruit size was measured at 50 DAFB and fruit will be harvested in Feb. 2000. These data should provide fresh insight and discussion into the respective roles of temperature and competition during the cell division fruit growth phase on apple fruit size.
684 Thinning and Crop Load Effects on Apple Fruit Growth
Authors: Greene Duane W.
Published: February 2019

Chemical thinners can be classified as either blossom thinners or postbloom thinners. Blossom thinners act by inhibit further pollination, pollen germination, or pollen tube growth. At petal fall it is not possible to distinguish between fruit that have been injured by blossom thinners, and those that will persist and continue to grow. The receptacles of blossom thinned fruit do not grow, whereas fruit that has not been treated and that also contain viable seeds, resumes growth within 4 to 6 days, depending upon temperature. Abscission of fruit treated with postbloom thinners does not usually occur until 1.5 to 3 weeks after application. Frequently, it is possible to identify fruit that will abscise and to make an initial assessment of thinning efficacy, within 4 to 6 days following application by measuring fruit growth rate. A reduction in fruit growth by as little as 15% to 20% less than rapidly growing fruit is usually sufficient to assume that the fruit will abscise sometime during the June drop period. The effects of specific chemical thinners on fruit growth and subsequent thinning will be discussed.
A Student-driven Landscape Design for a New Academic Building
Authors: Stevenson Elizabeth A. , Grueber Kevin L.
Published: February 2019

Berry College offers a unique environment for learning with 28,000 acres of forests, meadows, lakes, and streams. This distinctly beautiful setting has encouraged environmental awareness among students and faculty on campus. The construction of an academic building to house the School of Math and Natural Sciences in a previously undisturbed, wooded site prompted students and faculty to become interested in the preservation of the site's natural characteristics. Students in the horticulture program worked closely with the Director of Horticulture and the Academic Dean to develop a plan to create a landscape that was both educationally and environmentally sound.

The plan consisted of a detailed landscape design as well as the identification of the steps necessary to implement the design. The design incorporated ornamental plants and geological features native to the southeastern region of the United States with the plant species that existed on the site. The design contains such features as a wildflower meadow, an aquatic garden, rock gardens, and various native trees, shrubs, and groundcovers. Plant materials were properly labeled and brochures are made available to guests, students, and faculty interested in learning more about indigenous geological features and plant materials while touring the building and its landscape. The success of this project is due to the cooperation and participation of faculty, staff, and students and represents a unique learning opportunity.
Rooting Dogwood Microshoots
Authors: Sharma Anjana R. , Trigiano Robert N. , Witte Willard T. , Schwarz Otto J.
Published: February 2019

Cultivars of flowering dogwood (Cornus florida L.) are commercially propagated by vegetative methods such as rooting cuttings or grafting. The results of these methods can be unpredictable. A reliable method of producing dogwoods through tissue culture would be very useful to rapidly produce many copies of important genotypes with horticulturally important characters such as resistance to diseases. One of the primary difficulties of propagating dogwoods (seedlings only) by axillary bud multiplication has been the low rooting efficiency of the microshoots. Various treatments were tried in order to enhance rooting. Eighty-three percent of microshoots harvested between 5 and 7 weeks and treated continuously with 4.9 micromolar IBA rooted after 4 weeks, whereas <20% of microshoots harvested before 5 weeks and after 7 weeks rooted after 4 weeks of continuous exposure to IBA. Differences were also observed in rooting potentials of microshoots that had reddish brown stems rooting at a higher frequency compared to those that had green stems. We hope to translate this method to the propagation of cultivars and potential new releases.
High CO2 Storage Improves the Shelf Life of `Arapaho' and `Navaho' Blackberries
Authors: Perkins-Veazie P. , Collins J.K.
Published: February 2019

Application of modified-atmosphere storage (MA) (high carbon dioxide and/or low oxygen) extends the shelf life of several fruits. This study was done to determine the effects of MA on quality and flavor of blackberries. `Navaho' and `Arapaho' blackberries were harvested in 1998 and 1999, precooled overnight at 2 °C, and placed in 0.5-L treatment jars. Treatments of 15% CO2/10% O2 or of air (0.03% CO2/21% O2) were applied at 2 °C for 3, 7, or 14 days. After treatment application, jars were held at 2 °C for an additional 11, 7, or 0 days, respectively. Seven and 14 days of application of CO2 reduced the incidence of decayed and leaky berries by 10% to 20% for both `Arapaho' and `Navaho', but firm berries decreased 10% after 14 days of treatment. Titratable acidity was slightly lower, and pH higher, in control fruit but soluble solids content was not affected by treatment. Anthocyanin content was not affected by treatment in `Arapaho' berries but was lower in `Navaho' berries after 7 and 14 days of treatment. Samples taken for taste tests after 3 and 7 days of treatment had no off-odors or off-flavors. `Arapaho' and `Navaho' blackberries benefitted from high CO2 storage, with a minimum of 7 days of treatment application needed to increase marketable berries by 10%.
Potato Seed Piece Treatments for Controlling Rhizoctonia solani Infections
Authors: Schuster Greta , Roberts Roland E. , Bender David
Published: February 2019

Rhizoctonia solani infection of potato causes seed piece decay and stem and tuber lesions, resulting in delayed emergence and uneven stands, low-vigor plants and unmarketable tubers. Rhizoctonia prevention effectiveness of three fungicide/fir bark dusts and nontreated tubers were compared on three varieties. Seedpieces of Viking, Atlantic and Norkotah 278 were treated and planted in separate commercial fields. A randomized complete-block design with four replications with four 26-foot rows per treatment plot included four treatments: 0.5 lb Maxim, 1.0 lb Tops MZ, and 1.5 lb Nubark Captan dust/100 lb seed. Plant stems, stolons and tubers were examined for Rhizoctonia infection at the tuber initiation stage and tubers were examined again at mature stage. Maxim and Tops MZ reduced stolon infection in Atlantic and Norkotah 278 and reduced stem infection in Norkotah 278. Plants from Maxim treated tubers produced more stems/plant in Norkotah 278 and produced more weight of tubers weighing less than four oz in all three varieties. Differences in seed tuber conditioning and mechanical damage in seed handling increase variability of treatment effects. Repeated testing of potato seed piece treatments in Texas High Plains conditions is the best way to confirm potential of beneficial effects of seed treatment.
Consumer Evaluation of Selected Tomato Varieties
Authors: Cooper Paul , Stark Robert , Francis Paul , Allen Charles
Published: February 2019

Eight tomato varieties were evaluated in 1999 for consumer preference of appearance and taste. Fruits were collected from a tomato yield trial conducted at the Southeast Research and Extension Center at Monticello, Ark. Four of the varieties (`Mountain Spring', `Celebrity', `Better Boy', and `Early Girl') were red-fruited. Three (`Bradley', `Traveler 76', and `Pink Girl') were pink-fruited. One variety, `Mountain Gold', was yellow-fruited. Fruit evaluations were conducted on three separate dates. Varieties were ranked 1–8 by the taste panelists for both outward appearance and for taste. Appearance and taste were not correlated. `Mountain Spring' was ranked best in appearance, followed closely by `Pink Girl' and `Celebrity'. However, the panelists ranked `Mountain Spring' next to last (seventh) for taste. `Pink Girl' was ranked first in taste, followed by `Better Boy', `Bradley', `Celebrity', and `Early Girl'. `Mountain Gold' was ranked last (eighth) for both appearance and taste. These results indicate that consumers should not rely on appearance alone when purchasing tomatoes. The results also indicate that tomato producers should have a thorough knowledge of the market that they are serving.
Study of Apple Cultivars on Dwarfing Rootstocks in North Mississippi
Authors: Siswanto Usman , Matta Frank B.
Published: February 2019

This study was established to determine the influence of scion/stock combination on leaf area, yield efficiency, and fruit quality attributes in effort to identify the most suitable scion/stock combination for Mississippi. Twenty-nine scion/stock combinations were grown at the Pontotoc Ridge-Flatwoods Research and Extension Center, North Mississippi. The treatments were arranged in a completely randomized design (CRD) with six single tree replications. `Jon-A-Red' on Mark produced the smallest leaf area, while the largest leaf area was produced by the combination of `Royal Gala' on MM106 and `Blushing Golden' on M7A. Scion/stock combinations significantly affected yield efficiency, fruit yellow pigment dvelopment, firmness and fruit mineral composition. Scion cultivars on Mark resulted in the highest yield efficiency, except `Empire'. `Ultra Gold' and `Braeburn' on Mark and `Blushing Golden' on MM111 led to yellow pigmentation in the highest category. Meanwhile, `Braeburn' on Mark was among the scion/stock combinations that produced the firmest fruit. And fruit from trees on Mark consistently had high calcium (Ca) levels. After 7 years, `Royal Gala' on Mark produced the highest yield efficiency. `Braeburn' on Mark resulted in both the firmest fruit and the highest fruit Ca concentration.
The Auburn University Shade Tree Evaluation: Its Roots and Fruit
Authors: Williams J. David , Gilliam Charles H. , Keever Gary J. , Owens John
Published: February 2019

Auburn Univ.'s shade tree evaluation is an ongoing study comparing a moderately diverse range of species, varieties and cultivars of larger-growing trees. Initiated in 1980, there were 250 tree selections planted in three replications located at the Piedmont Substation near Camp Hill, Ala. Among the published “fruits” of the evaluation have been critical comparisons of 10 Acer rubrum selections with respect to growth and fall color characteristics; growth rate and aesthetic characteristics of fourteen Quercus selections; growth and fireblight susceptibility of 10 Pyrus calleryana selections; and the best performing trees overall in the first 12 years of the study. The shade tree evaluation has served as an important precedent for initiation of six additional landscape tree tests in Alabama. Besides its benefits as a research project, the shade tree evaluation has provided a living laboratory for a wide range of educational audiences including landscape and nursery professionals, county extension agents, urban foresters, Master Gardeners, garden club members, and horticulture students. Knowledge gained from the shade tree evaluation has also been shared through presentations at many meetings and conferences.
Influence of Storage and Sanitizing Protocols on the Physiology of Fresh-Cut Watermelon
Authors: Fonseca Jorge M. , Rushing James W. , Testin Robert F.
Published: February 2019

Fresh-cut watermelon cubes stored at selected temperatures within the range of 1.1 to 14.5 °C had decreasing quality shelf life corresponding with increasing temperature. At lower temperatures there was a random occurrence of chilling injury symptoms in some cubes that was associated with the section of watermelon from which the cubes were cut. Cubes removed from the top side of the intact watermelon fruit were more susceptible to chilling injury than cubes from other sectors of the fruit. Sanitizing cubes with chlorine (40 μL·L–1) or ozone (0.04 μL·L–1) solutions caused an initial reduction in microbial count but during storage the effect diminished and became insignificant compared to controls. Overall quality was lower in cubes receiving aqueous sanitizing treatments, possibly due to mechanical injury occurring during centrifugation to remove excess solution. Overall quality of cubes exposed to UV light (≈250 nm for 1–5 min) was better than cubes receiving aqueous sanitizing treatment. The effectiveness of UV treatment in reducing microbial load was dependent on the amount of cube surface exposed to the light. The results emphasize the importance of preventing microbial contamination during processing of fresh-cut watermelon.
Measuring Blackberry Firmness Rapidly: A Comparison of Subjective Ratings and Instrumented Compression Measurements
Authors: Perkins-Veazie P. , Armstrong P. , Clark J.R
Published: February 2019

Firmness of blackberries greatly determines shelf life for fresh market. Firmness in blackberries appears to be due to a combination of skin toughness and internal receptacle to permit large sample size measurements. Subjective rating of fruit require consistent evaluation by raters over harvest dates and years, and is subject to fatigue error. The FirmTech2 firmness tester was developed to provide rapid compression measurements and has been successfully used in determining the firmness of cherries and blueberries. Blackberries from a large number of clones ranging in firmness from rock-hard to squishy were measured with the FirmTech2 using a deformation range of 25 to 100 g. Additionally, blackberries were placed in storage at 2, 5, and 2/20 °C to monitor effects of storage temperature on blackberry firmness. Berries were subjectively rated and then placed on the Firmtech for measurements. A comparison of firmness readings for fruit only in the “1” (firm) category was made. Differences found among fruit readings agreed with observed differences in field subjective ratings. Stored fruit that had become soft and mushy could not be statistically differentiated from firmer fruit in quantitative readings. In conclusion, the Firmtech2 allowed rapid evaluation of breeding lines before storage.
Bolting and Growth of Spinacia oleracea L. Can be Altered by Modifying the Photoperiod during Transplant Production
Authors: Chun Changhoo , Watanabe Ayumi , Kozai Toyoki , Kim Hyeon-Hye , Fuse Junya
Published: February 2019

Spinach (Spinacia oleracea L. cv. Dimple) was chosen to determine whether bolting (i.e., elongation of flower stalks) could be controlled by manipulating the photoperiod during transplant production in a closed system using artificial light. Plants grown under various photoperiods during transplant production were transferred and cultured under natural short photoperiods and artificial long photoperiods. Vegetative growth at transplanting tended to be greater with the longer photoperiod because of the increased integrated photosynthetic photon flux. Bolting initiation reacted qualitatively to a long photoperiod, and the critical photoperiod for bolting initiation was longer than 13 h and shorter than 15 h. The plants grown under a longer photoperiod during transplant production had longer flower stalks at harvest. The long photoperiod and/or high temperature after transplanting therefore promoted flower stalk elongation. Growing plants under a photoperiod that was shorter than the critical photoperiod during transplant production reduced elongation of the flower stalks, thus there was no loss of market value even though the plants were cultured under a long photoperiod and high temperature for 2 weeks after transplanting.
pH Dominates Leucadendron `Safari Sunset' Growth
Authors: Silber Avner , Ackerman Alexander , Mitchnick Boris , Ganmore-Neumann Ruth , Ben-Jaacov Jaacov
Published: February 2019

The objectives of the present research were to study the effects of pH, NH4:NO3 ratio, and P concentration in the nutrient solution on development of Leucadendron R. Br. `Safari Sunset' [L. salignum Bergius × L. laureolum (Lam.) Fourc.]. The experiment was conducted in aero-hydroponic systems and involved six treatments in a nonfactorial design: two pH levels (5.5 and 7.5), two P levels (7 and 20 mg·L–1), and two NH4:NO3 ratios (60:40 and 25:75). The pH of the root environment was the most important factor controlling growth. Root cells were longer in plants grown at pH 5.5 than at pH 7.5, but width was not affected. Altering the NH4:NO3 ratio did not affect development regardless of pH. Increasing the P concentration from 7 to 20 mg·L–1 significantly decreased root fresh weight at the low pH and slightly reduced shoot growth. Nitrogen, P, K, Zn, and Mn concentrations were higher, while that of Fe was lower in plants grown at low pH. Reducing the NH4:NO3 ratio did not affect N concentration but increased P and K concentrations in the shoots. Increasing the P concentration significantly raised the P content of shoot and root tissues but reduced the content of Fe, Zn, and Mn.
Comparisons of Root Morphology in Susceptible and Tolerant Melon Cultivars before and after Infection by Monosporascus cannonballus
Authors: Crosby Kevin , Wolff David , Miller Marvin
Published: February 2019

The fungus Monosporascus cannonballus Pollock and Uecker infects melon (Cucumis melo L.) roots and causes root rot/vine decline disease, which has reduced productivity of commercial muskmelon and honeydew cultivars in South Texas. To assess the impact of the fungus on several root traits, two greenhouse experiments were carried out over two seasons. A comparison of inoculated vs. control root systems was carried out with four melon cultivars representing both susceptible (`Magnum 45' and `Caravelle') and tolerant types (`Deltex' and `Doublon'). The sand medium was inoculated with 50–60 colony forming units (CFUs) per gram of the severe Monosporascus strain, TX90-25. After a 30-day growth period, the control and inoculated root systems were carefully cleaned and evaluated. Roots were scanned by a computer and the data were analyzed by the Rhizo Pro 3.8 program. The traits of interest included total root length, average root diameter, number of root tips, number of fine roots (0–0.5 mm), and number of small roots (0.5–1 mm). Significant differences existed between the two tolerant cultivars and the two susceptible ones for four of the traits. Total root length, fine and small root length, and root tip number were greater for `Deltex' than for both susceptible cultivars and greater for `Doublon' than for `Caravelle'. The results suggest that tolerance to this pathogen is closely linked to the integrity of the root structure. The potential for improving root vigor to combat root rot/vine decline merits further investigation.
Aroma Volatiles of Mature-green and Tree-ripe `Tommy Atkins' Mangoes after Controlled Atmosphere vs. Air Storage
Authors: Bender R.J. , Brecht J.K. , Baldwin E.A. , Malundo T.M.M.
Published: February 2019

To determine the effects of fruit maturity, storage temperature, and controlled atmosphere (CA) on aroma volatiles, mature-green (MG) and tree-ripe (TR) `Tommy Atkins' mangoes (Mangifera indica L.) were stored for 21 days in air or in CA (5% O2 plus 10% or 25% CO2). The MG fruit were stored at 12 °C and the TR fruit at either 8 or 12 °C. Homogenized mesocarp tissue from fruit that had ripened for 2 days in air at 20 °C after the 21-day storage period was used for aroma volatile analysis. The TR mangoes produced much higher levels of all aroma volatiles except hexanal than did MG fruit. Both MG and TR mangoes stored in 25% CO2 tended to have lower terpene (especially p-cymene) and hexanal concentrations than did those stored in 10% CO2 and air-stored fruit. Acetaldehyde and ethanol levels tended to be higher in TR mangoes from 25% CO2 than in those from 10% CO2 or air storage, especially at 8 °C. Inhibition of volatile production by 25% CO2 was greater in MG than in TR mangoes, and at 8 °C compared to 12 °C for TR fruit. However, aroma volatile levels in TR mangoes from the 25% CO2 treatment were in all cases equal to or greater than those in MG fruit treatments. The results suggest that properly selected atmospheres, which prolong mango shelf life by slowing ripening processes, can allow TR mangoes to be stored or shipped without sacrificing their superior aroma quality.
Percentage of Dry Matter and Oil Content Are Not Reliable Indicators of Fruit Maturity or Quality in Late-harvested `Hass' Avocado
Authors: Hofman Peter J. , Jobin-Décor Marcelle , Giles Janet
Published: February 2019

The potential to use percentage of dry matter (DM) and/or oil of the flesh of `Hass' avocado as a maturity standard to determine the latest harvest for acceptable fruit quality, was investigated. `Hass' avocado fruit were harvested from early October to mid-January from a commercial orchard in subtropical Queensland. The percentage of DM and oil changed little during the harvest period, and the eating quality of the flesh remained high. However, the incidence of body rots (caused mainly by Colletotrichum sp.) and the flesh disorders grey pulp and vascular browning, increased with harvest. These results indicate that percentage of DM and oil are not reliable late-maturity standards because of the inconsistent change with later harvests, and that disease and internal disorders can be the main determinants of latest acceptable harvest, rather than eating quality.
Nondestructive Methods to Estimate Leaf Area in Vitis vinifera L.
Authors: Montero F.J. , de Juan J.A. , Cuesta A. , Brasa A.
Published: February 2019

The importance of rapid, nondestructive, and accurate measurements of leaf area (LA) in agronomic and physiological studies is well known, but a search of the literature revealed little information available for grape (Vitis vinifera L.). The results described herein include a comparison of 12 different mathematical models for estimating leaf area in `Cencibel'. The simplest, most accurate regression equations were: LAi = 0.587 LW (R2 = 0.987) and LAi = 0.588 LW (R2 = 0.994), where LAi is leaf area measured using image analysis and LW is leaf length × maximum width. Use of maximum width (W), leaf length (L), petiole length (Lp), and dry weight of leaves (DML) as single variables in the regression equations were not as closely associated with total leaf area, although their R2 values were also highly significant.
Complete Sequences of the S-genes, Sd- and Sh-RNase cDNA in Apple
Authors: Kitahara Kentaro , Soejima Junichi , Komatsu Hiromitsu , Fukui Hirokazu , Matsumoto Shogo
Published: February 2019

The S-locus genes in the pistil (S-RNases) were cloned from the apple (Malus ×domestica Borkh.) cultivar Akane (S-genotype SdSh from pollination analysis). The Sd- and Sh-RNase corresponded to S7- and S24-RNase, which have been cloned from `Idared' and `Braeburn', respectively. Sh-RNase was very similar to Sf- and Sg-RNases at the deduced amino acid-sequence levels (93%). We developed an S-allele specific polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis method for distinguishing the Sh from Sf and Sg, and the Sh-alleles of `Akane', `Touhoku 2', `Vista Bella', and `Worcester Pearmain' were identified. We also identified the S-allele genotypes of 16 apple cultivars.
Use of Amplified Fragment Length Polymorphism Markers for Celery Cultivar Identification
Authors: Li Genyi , Quiros Carlos F.
Published: February 2019

DNA samples from 21 cultivars of celery (Apium graveolens L. var. dulce) were subjected to amplified fragment length polymorphism (AFLP) analysis. The most informative adapter combination was EcoRI-TaqI. All cultivars could be distinguished from each other by their unique fingerprints based on 73 markers. The program NTSYS grouped the cultivars in three main clusters according to their origin. The groupings observed agreed, with a few exceptions, with those expected by historical accounts and previous analyses based on biochemical and ramdomly amplified polymorphic DNA (RAPD) markers.
Small Inflorescence Bulbils Are Best for Micropropagation and Virus Elimination in Garlic
Authors: Ebi M. , Kasai N. , Masuda K.
Published: February 2019

Garlic (Allium sativum L.) plants were cultured from immature inflorescence bulbils. The primordia of bulbils appeared initially as protuberances on reproductive apices, swelled, and then formed bulbils with protective leaves. Excised bulbils sprouted on Murashige and Skoog's medium with 5.4 μm naphthaleneacetic acid (NAA) and grew into plantlets. The frequency of sprouting in culture increased with the development of bulbils before excision, and immature bulbils 0.4 to 2.4 mm in diameter sprouted at a frequency of >85%. A dot immunoblot assay revealed a remarkable reduction in levels of garlic mite-borne mosaic virus in plantlets grown from immature bulbils, suggesting that such bulbils might be suitable for the propagation of virus-free garlic plants.
Morphology, Growth, and Rhizome Development of Vaccinium angustifolium Ait. Seedlings, Rooted Softwood Cuttings, and Micropropagated Plantlets
Authors: Morrison Sharon , Smagula John M. , Litten Walter
Published: February 2019

For accelerating the filling in of bare areas in native lowbush blueberry fields or converting new areas to production, micropropagated plantlets rooted after three subcultures outperformed seedlings and rooted softwood cuttings. After 2 years of field growth, they averaged 20.3 rhizomes each of average dry weight 3.5 g, as compared with 5.7 rhizomes of average dry weight 1.1 g for rooted softwood cuttings. After 1 year of field growth, seedlings produced on average 3.3 vs. 0.4 rhizomes from micropropagated plants that had not been subcultured and 0.3 rhizomes from stem cuttings. Apparently, subculturing on cytokinin-rich media induces the juvenile branching characteristic that provides micropropagated plants with the desirable morphologies and growth habits of seedlings. These characteristics favor rhizome production while the benefits of asexual reproduction are retained. The advantage in rhizome production of micropropagation over stem cuttings varied among clones.
Control of Bacterial Spot on Tomato in the Greenhouse and Field with H-mutant Bacteriophages
Authors: Flaherty J.E. , Somodi G.C. , Jones J.B. , Harbaugh B.K. , Jackson L.E.
Published: February 2019

A mixture of host-range mutant (h-mutant) bacteriophages specific for tomato race 1 (T1) and race 3 (T3) of the bacterial spot pathogen, Xanthomonas campestris pv. vesicatoria (Doidge) Dye was evaluated for biological control of bacterial spot on `Sunbeam' tomato (Lycopersicon esculentum Mill.) transplants and field-grown plants for two seasons (Fall 1997 and Fall 1998). Foliar applications of bacteriophages were compared with similar applications of water (control) and of copper/mancozeb bactericides, the commonly used chemical control strategy for tomato seedling and field production. In 1997, the incidence of bacterial spot on greenhouse-grown seedlings was reduced from 40.5% (control) to 5.5% or 0.9% for bactericide- or bacteriophage-treated plants, respectively. In 1998, the incidence of bacterial spot was 17.4% on control plants vs. 5.5% and 2.7% for bactericide- and bacteriophage-treated plants, respectively, although these differences were not statistically significant at P ≤ 0.05. Applications of bacteriophages to field-grown tomatoes decreased disease severity as measured by the area under the disease progress curve (AUDPC) by 17.5% (1997) and 16.8% (1998) compared with untreated control plants. Preharvest plant vigor ratings, taken twice during each field season, were higher in the bacteriophage-treated plants than in either bactericide-treated plants or nontreated controls except for the early vigor rating in 1998. Use of bacteriophages increased total weight of extra-large fruit 14.9% (1997) and 24.2% (1998) relative to that of nontreated control plants, and 37.8% (1997) and 23.9% (1998) relative to that of plants treated with the chemical bactericides. Chemical names used: manganese, zinc, carboxyethylene bis dithiocarbamate (mancozeb).
Germination of Papaya Seed in Response to Desiccation, Exposure to Subzero Temperatures, and Gibberellic Acid
Authors: Salomão Antonieta N. , Mundim Rosângela C.
Published: February 2019

The effects on germination of two lots of Carica papaya seed of dehydration at 25 °C, followed by exposure to -20 °C or -196 °C, were evaluated with and without gibberellic acid (GA3) treatment. In the absence of GA3 treatment, dehydration increased subsequent germination only in seed lot 1 when moisture content (m.c.) was reduced from 59% to 6.0% and 5.3%. In seed lot 2, dehydration followed by exposure to -196 °C increased germination compared with dehydration alone. Treatment with GA3 enhanced germination rate in all treatments. Dehydration to 5.3% (lot 1) or 6.9% and 6.8% m.c. (lot 2), followed by exposure to subzero temperatures and treatment with GA3, were the most favorable combined treatments to enhance papaya seed germination. The results suggest that papaya seed presents an orthodox behavior, permitting germplasm conservation in conventional and cryogenic genebanks.
Use of Preference Testing to Identify Tolerance Limits for Fruit Visual Attributes in Apple Breeding
Authors: Hampson C.R. , Quamme H.A.
Published: February 2019

Sensory evaluation methods were used to establish tentative guidelines for screening apple (Malus ×domestica Borkh.) breeding selections for four visual attributes. A panel of 42 regional consumers rated sample selections for fruit size on the 7-point “Just Right” (JR) scale, for fruit shape on a 7-point hedonic (liking) scale, and for the appearance of lenticels and stem bowl russet (SBR) on a 7-point affective (acceptability) scale. The panel most preferred a fruit about 7.5 cm in diameter. No evidence was found for range bias or for differences between yellow and red apples in size preference. Women and panelists over 55 years of age tended to prefer a slightly smaller apple. Panelists liked all the most common apple shapes. Lenticels generally became unacceptable when they exceeded 1.0 mm in diameter, but lenticel density was not related to acceptability. For red or yellow apples, SBR was acceptable on average, provided its maximum extent did not exceed about 55% of the fruit diameter. The panel's tolerance to SBR resembled that of a larger regional population, and their fruit size preferences resembled those reported elsewhere for European consumers. Similar methods could be used by other breeders to assess the preferences of their target consumer population.
Flowering and Fruit Set of Pumpkin Cultivars under Field Conditions
Authors: Stapleton Suzanne Cady , Wien H. Chris , Morse Roger A.
Published: February 2019

Field experiments with six pumpkin cultivars (Cucurbita pepo L.) were conducted in Ithaca, N.Y., in 1992 and 1993 to characterize the patterns of flowering and fruit set. Plants of all cultivars produced the greatest number of female flowers and exhibited the highest rate of fruit set 35-45 days after transplanting, during the first 2 weeks of greatest flower production (“peak bloom”). During the 3 weeks of peak bloom, each plant produced an average of 3.4 pistillate flowers in 1992 and 5.4 in 1993, and fruit set was 50.9% in 1992 and 74.6% in 1993, yielding 1.7 and 4.0 fruit per plant, respectively. In 1994, flower production was further studied with the cultivar Wizard. Flowers were produced in a ratio of 33 staminate to 1 pistillate flower over the entire season. Climatic conditions appeared to be secondary to physiological factors in affecting flowering and fruit set during all three seasons. Characterization of fruit set patterns in pumpkin may aid producers in scheduling pollination services and predicting yields.
The Relationship Between Leaf Area and Light Interception by Spur and Extension Shoot Leaves and Apple Orchard Productivity
Authors: Wünsche Jens N. , Lakso Alan N.
Published: February 2019

The study evaluated the relationship of spur vs. extension shoot leaf area and light interception to apple (Malus {XtimesX}domesticaBorkh.) orchard productivity. Fifteen-year-old `Marshall McIntosh'/M.9 trees had significantly greater leaf area and percentage of light interception at 3-5 and 10-12 weeks after full bloom (AFB) than did 4-year-old `Jonagold'/Mark trees. Despite significant increases in leaf area and light interception with canopy development, linear relationships between total, spur, and extension shoot canopy leaf area index (LAI) and 1) light interception and 2) fruit yield were similar at both times. Mean total and spur canopy LAI and light interception were significantly and positively correlated with fruit yield; however, extension shoot LAI and light interception were poorly correlated with yield. In another study total, spur and extension shoot canopy light interception varied widely in five apple production systems: 15-year-old central leader `Redchief Delicious' MM.111, 15-year-old central leader `Redchief Delicious' MM.111/M.9, 16-year-old slender spindle `Marshall McIntosh' M.9, 14-year-old `Jerseymac' M.9 on 4-wire trellis, and 17-year-old slender spindle `MacSpur' M.9. Yields in these orchards were curvilinearly related to total and extension shoot canopy light interception and decreased when total light interception exceeded 60% and extension shoot interception exceeded 25%. Fruit yields were linearly and highly correlated (r2 = 0.78) with spur light interception. The findings support the hypothesis that fruit yields of healthy apple orchards are better correlated with LAI and light interception by spurs than by extension shoots. The results emphasize the importance of open, well-illuminated, spur-rich tree canopies for high productivity.
Effects of Alcohol Vapors and Oxygen Stress on Superficial Scald and Red Color of Stored `Delicious' Apples
Authors: Ghahramani F. , Scott K.J. , Holmes R.
Published: February 2019

`Delicious' (Malus ×domestica Borkh.) apples were kept in sealed polyethylene bags (thickness 0.05 mm) and exposed to ethanol, propan-1-ol, butan-1-ol, and pentan-1-ol during storage at 0 °C. Rates of application varied from 1.85 to 120 mmol·kg-1. Complete control of superficial scald was achieved using 30 mmol·kg-1 of fruit with butan-1-ol or propan-1-ol; ethanol required 120 mmol·kg-1 to control the disorder, but at this concentration, purpling of the red skin occurred. Butan-1-ol and propan-1-ol did not affect the color. Pentan-1-ol caused severe skin injury resembling soft or deep scald of `Jonathan' apples. Apples were also kept in high purity N at 20 °C for up to 8 days before storage at 0 °C. Complete control of scald occurred with a 6- or 8-day exposure to N. Control of scald appears to be due to the accumulation of ethanol during exposure to N. Nitrogen treatments did not affect skin color.
Pleiotropic Effects in Transgenic Tobacco Plants Expressing the Oryzacystatin I Gene
Authors: Gutiérrez-Campos Rafael , Torres-Acosta Juan Antonio , de Jesús Pérez-Martínez José , Gómez-Lim Miguel Angel
Published: February 2019

A study was undertaken to evaluate possible phenotypic alterations in transgenic tobacco (Nicotiana tabacum L. cv. Xanthi) plants expressing the oryzacystatin I gene. Morphophysiologic parameters, such as growth rate, biomass, and leaf, flower, and fruit characteristics were analyzed. Transgenic plants overexpressing the cysteine proteinase inhibitor showed increased growth rate and dry weight, earlier flowering, and increased numbers of flowers and seeds. These pleiotropic effects were correlated with expression level of oryzacystatin I in transgenic lines. The results suggest that oryzacystatin I disrupts the normal activity of cysteine proteinases, which are involved in important physiological processes.
Economic Analysis of Adopting Zero Runoff Subirrigation Systems in Greenhouse Operations in the Northeast and North Central United States
Authors: Uva Wen-fei L. , Weiler Thomas C. , Milligan Robert A.
Published: February 2019

Zero runoff subirrigation (ZRS) technology is a promising method of managing fertilizer and pesticide inputs while improving production efficiency. However, high capital investment costs and inadequate technical information available to growers are major impediments to initiating the change. This study quantifies costs and returns associated with adopting ZRS systems and compares the profitability of four alternative ZRS systems (ebb-and-flow benches, Dutch movable trays, flood floors, and trough benches) for greenhouse operations in the northeastern and north central United States. The capital investment analysis showed that the Dutch movable tray system was most profitable for small potted plant production, and the flood floor system was most profitable for large potted plant and bedding crop flat production. Sensitivity analysis showed that changes in cost variables generally did not affect the profitability rankings of the alternative ZRS investment projects. Nonetheless, the flood floor system gained slight advantages when the product price increased, and the Dutch movable tray system gained advantages as the hourly labor cost increased.
Total and Individual Glucosinolate Content in 11 Broccoli Cultivars Grown in Early and Late Seasons
Authors: Rosa Eduardo A.S. , Rodrigues Ana S.
Published: February 2019

Broccoli (Brassica oleracea L. Italica Group) is an economically important vegetable crop and its consumption may benefit human health. Glucosinolates, a group of secondary plant metabolites found generally in the cultivated Brassicaceae, may protect against the development of certain malignancies. The objective of this study was to evaluate total and individual glucosinolate content of broccoli cultivars widely grown in southern Europe following spring vs. summer planting (early vs. late crop, respectively). Glucosinolates in primary and secondary inflorescences taken from mature plants were analyzed separately by high performance liquid chromatography (HPLC). The cultivars contained primarily 4-methylsulfinylbutyl-, indol-3-ylmethyl- and 1-methoxyindol-3-ylmethyl-glucosinolates. Total and individual glucosinolate levels varied significantly between seasons, among cultivars and between inflorescences. `Shogun' contained the highest total glucosinolate levels (between 35.2 mmol·kg-1 dry weight in primary inflorescences of the early crop and 47.9 in secondary inflorescences of the late crop). Total and individual glucosinolate levels were generally higher in the late than in the early crop. Primary inflorescences generally contained the highest glucosinolate levels in the early crop but secondary inflorescences had the highest levels in the late one.
Plant Density Affects Yield, Yield Components, and Color of Direct-seeded Paprika Pepper
Authors: Cavero J. , Ortega R. Gil , Gutierrez M.
Published: February 2019

Paprika pepper (Capsicum annuum var. annuum L., `Agridulce SIA') was direct-seeded on raised beds in double rows 0.35 cm apart. Plants were thinned within the row to establish densities ranging from 13,333 to >500,000 plants/ha. Yield of paprika pepper increased as plant density increased, but plant densities >200,000 plants/ha resulted in only small increases in yield. Fruit number and dry fruit weight/plant decreased with increasing plant populations, and weight/fruit decreased slightly. The increase in yield/ha as plant density increased was a result of increased numbers of fruits/ha. Pigment content (ASTA units) declined linearly as plant density increased, whereas moisture content of red fruits at harvest remained unaffected. Plant densities in the range of 150,000 to 200,000 plants/ha were optimal in terms of fruit yield and pigment content.
Light, Temperature, and Sucrose Affect Color, Diameter, and Soluble Solids of Disks of Wax Apple Fruit Skin
Authors: Shü Zen-hong , Chu Cheng-chung , Hwang Lee-juan , Shieh Ching-shung
Published: February 2019

A study was conducted to assess the combined effects of light, temperature and sucrose on color, weight, diameter, and soluble solids of the skin of wax apple (Syzygium samarangense Merr. & Perry) fruits. Skin disks were cultured in a factorial arrangement of two light levels [dark or light (300 μmol·m-2·s-1)] as subplots and three sucrose concentrations (0%, 3%, or 6%) as sub-subplots within three temperature levels (20, 25, or 30 °C) as whole plot treatments. Weight, diameter, soluble solids concentration (SSC), and anthocyanin content were measured 2 weeks after incubation. Light increased SSC and anthocyanin, but reduced the increase in weight and diameter. Increasing the temperature limited increase in diameter and anthocyanin content. Weight, SSC, and anthocyanin contents increased in a linear fashion with concentration of sucrose in the culture solution. However, none of the three factors played a unique role in anthocyanin synthesis in wax apple. Among the 18 combinations, light/20°C/6% sucrose gave the highest SSC and anthocyanin content, while dark/20°C/6% sucrose produced the largest diameter.