bluuebunny/crossref_metadata_2025 huggingface dataset:
Biosolids Impact Antioxidant Metabolism Associated with Drought Tolerance in Tall Fescue
Authors: Zhang Xunzhong , Zhou Damai , Ervin Erik H. , Evanylo Greg K. , Cataldi Derik , Li Jinling
Published: February 2019

The presence of biologically active substances (BAS) in biosolids may enhance plant stress tolerance and growth, but the underlying mechanisms are not well understood. This greenhouse study investigated the effects of two biosolids: Alexandria (anaerobically digested; Class A product from the Alexandria Sanitation Authority Wastewater Treatment Facility in Alexandria, VA) and Blue Plains (lime-stabilized; Class B product from Washington, DC, Water and Sewer Authority) on tall fescue [Lolium arundinaceum (Schreb.) S.J. Darbyshire] antioxidant enzyme activity associated with drought resistance. Treatments included a fertilizer control, Alexandria (11.9 g·kg−1 soil) and Blue Plains (17.6 g·kg−1 soil) biosolids to match the nitrogen in the control. Tall fescue physiological responses were measured under well-watered or drought-stressed conditions. Drought stress reduced turfgrass quality, photochemical efficiency (PE), and catalase (CAT) activity while increasing superoxide dismutase (SOD), ascorbate peroxidase (APX), and peroxidase (POD) activities. The two biosolids improved turfgrass quality and root mass under both soil moisture regimes and delayed leaf wilting during moisture stress. The biosolids also improved PE, SOD, and APX activities relative to the control under both soil moisture regimes. The data suggest that biosolids application may improve antioxidant enzyme activity and subsequent drought resistance.
Morphology and Inheritance of Double Floweredness in Catharanthus roseus
Authors: Chen Chin-Mu , Wei Tzu-Yao , Yeh Der-Ming
Published: February 2019

A double-flowered periwinkle [Catharanthus roseus (L.) G. Don.] mutant TYV1 was identified and the morphology and inheritance of the double-flowered phenotype was studied. TYV1 has an outer salverform whorl of petals and an additional inner funnel-shaped whorl of petals originating from the apex of the corolla. The apex of corolla tube forms a narrow opening. There are hairs under the opening at the apex. The stigma in this mutant is set below the anthers. The overlap between the top end of the pistil and bottom ends of anthers in TYV1 flowers at 1 to 2 days after anthesis is 0.56 ± 0.01 mm. TYV1 could be used as either the male or female parent in crossing. Self-pollinated TYV1 produced all double-flowered progeny compared with self-pollinated single-flowered cultivars Little Pinkie and Titan Burgundy, which produced all single-flowered progeny. F1 plants between TYV1 and ‘Little Pinkie’ or ‘Titan Burgundy’ were all single. Three F2 populations segregated into 3 single: 1 double ratio. Backcrossing F1 to seed parents also indicated that a double-flowered form was controlled by a recessive allele. A single dominant gene expressed in the homozygous or heterozygous state resulted in the single-flowered phenotype. All the young seedlings of self-pollinated TYV1 and double-flowered progeny had distorted leaves before the sixth pair of leaves emerged.
Changes in Selected Quality Attributes of Greenhouse Tomato Fruit as Affected by Pre- and Postharvest Environmental Conditions in Year-round Production
Authors: Kubota Chieri , Kroggel Mark , Torabi Mohammad , Dietrich Katherine A. , Kim Hyun-Jin , Fonseca Jorge , Thomson Cynthia A.
Published: February 2019

‘Durinta’ tomatoes were grown hydroponically using rockwool substrate in greenhouses to assess the seasonal and postharvest changes of selected quality attributes including lycopene and total soluble solids (TSS, % Brix) concentrations in fruit when grown under varied electrical conductivity (EC) in the nutrient solution. Two levels of EC examined in this study were 2.4 and 4.8 dS·m−1 for standard low EC and high EC treatments, respectively. All fruits at light-red and red ripeness stages were harvested and weighed every week, and nine fruits visually representing the median group of red fruits were selected from each EC treatment and subject to measurements of lycopene and TSS concentrations. Of 53 harvest weeks (Dec. 2005 to Dec. 2006), 45 weeks were subject to fruit quality analyses at harvest and 3 weeks were subject to postharvest quality analyses. Lycopene concentration and TSS showed seasonal differences with larger variation in lycopene, but the high EC treatment induced an overall average of 18% greater lycopene concentration and a 20% greater TSS. The regression analyses indicated that efflux solution EC (EEC) was the most influential factor for both lycopene and TSS concentrations, but secondary influential factors were greenhouse temperature for lycopene and daily light integral for TSS. Postharvest storage test showed that selected fruit quality attributes (lycopene, TSS, ascorbic acid, and total phenolics) changed minimally or not at all for 10 days when stored at 12 °C, a widely recommended tomato postharvest storage temperature. Overall, we consider that producing lycopene-rich tomato by controlling EC of nutrient solution was feasible during year-round greenhouse production using a high-wire rockwool culture system.
Comparative Study of Color, Pungency, and Biochemical Composition in Chili Pepper (Capsicum annuum) Under Different Light-emitting Diode Treatments
Authors: Gangadhar Baniekal Hiremath , Mishra Raghvendra Kumar , Pandian Gobinath , Park Se Won
Published: February 2019

Color and pungency are the two main factors of chili peppers that determine their quality and final market price. In this study, we investigated the effect of light-emitting diodes (LEDs) on fruit color and primary and secondary metabolites (capsaicinoids) in Capsicum annuum L. cv. Cheonyang. High-performance liquid chromatography analysis of acetonitrile extract of chili fruits revealed enhanced capsaicinoid contents in blue LEDs (180 ± 6.32 mg/100 g) when compared with fluorescent light (54 ± 3.12 mg/100 g). However, color of chili pepper was remarkably changed under different light treatments. Among these, high ASTA color values and chromatic parameters (L*, a*, b*, C*, and H°) were recorded under red plus blue LED, further indicating red plus blue LED is responsible for most vivid color development compared with monochromatic red or blue LEDs. In addition, we found total carbohydrate [22.32 mg·g−1 fresh weight (FW)], reducing sugars (8.27 mg·g−1 FW), starch (14.05 mg·g–1 FW), carotenoids (6.15 mg·g−1 FW), and protein (4.83 mg·g−1 FW) were significantly high under red plus blue LED. These results showed that there were significant differences of plant growth and production of various metabolites among the different LEDs. Furthermore, blue LED showed a relatively higher rate of capsaicinoid production and red plus blue LED produced striking color development in chili peppers. Therefore, the results presented here might serve as an alternative strategy for nutritional improvement (color, oleoresin, and pungency) of chili peppers.
Nitrogen Requirements and N Status Determination of Lettuce
Authors: Bottoms Thomas G. , Smith Richard F. , Cahn Michael D. , Hartz Timothy K.
Published: February 2019

As concern over NO3-N pollution of groundwater increases, California lettuce growers are under pressure to improve nitrogen (N) fertilizer efficiency. Crop growth, N uptake, and the value of soil and plant N diagnostic measures were evaluated in 24 iceberg and romaine lettuce (Lactuca sativa L. var. capitata L., and longifolia Lam., respectively) field trials from 2007 to 2010. The reliability of presidedressing soil nitrate testing (PSNT) to identify fields in which N application could be reduced or eliminated was evaluated in 16 non-replicated strip trials and five replicated trials on commercial farms. All commercial field sites had greater than 20 mg·kg−1 residual soil NO3-N at the time of the first in-season N application. In the strip trials, plots in which the cooperating growers’ initial sidedress N application was eliminated or reduced were compared with the growers’ standard N fertilization program. In the replicated trials, the growers’ N regime was compared with treatments in which one or more N fertigation through drip irrigation was eliminated. Additionally, seasonal N rates from 11 to 336 kg·ha−1 were compared in three replicated drip-irrigated research farm trials. Seasonal N application in the strip trials was reduced by an average of 77 kg·ha−1 (73 kg·ha−1 vs. 150 kg·ha−1 for the grower N regime) with no reduction in fresh biomass produced and only a slight reduction in crop N uptake (151 kg·ha−1 vs. 156 kg·ha−1 for the grower N regime). Similarly, an average seasonal N rate reduction of 88 kg·ha−1 (96 kg·ha−1 vs. 184 kg·ha−1) was achieved in the replicated commercial trials with no biomass reduction. Seasonal N rates between 111 and 192 kg·ha−1 maximized fresh biomass in the research farm trials, which were conducted in fields with lower residual soil NO3-N than the commercial trials. Across fields, lettuce N uptake was slow in the first 4 weeks after planting, averaging less than 0.5 kg·ha−1·d−1. N uptake then increased linearly until harvest (≈9 weeks after planting), averaging ≈4 kg·ha−1·d−1 over that period. Whole plant critical N concentration (Nc, the minimum whole plant N concentration required to maximize growth) was estimated by the equation Nc (g·kg−1) = 42 − 2.8 dry mass (DM, Mg·ha−1); on that basis, critical N uptake (crop N uptake required to maintain whole plant N above Nc) in the commercial fields averaged 116 kg·ha−1 compared with the mean uptake of 145 kg·ha−1 with the grower N regime. Soil NO3-N greater than 20 mg·kg−1 was a reliable indicator that N application could be reduced or delayed. Neither leaf N nor midrib NO3-N was correlated with concurrently measured soil NO3-N and therefore of limited value in directing in-season N fertilization.
Evaluation of Cold Hardiness in Seven Iranian Commercial Pomegranate (Punica granatum L.) Cultivars
Authors: Ghasemi Soloklui Ali Akbar , Ershadi Ahmad , Fallahi Esmaeil
Published: February 2019

Freezing injury is one of the most important limiting factors in commercial pomegranate production. The objectives of this study were to compare cold hardiness of seven Iranian pomegranate cultivars at three stages: November, January, and March, and to investigate the relationship between freezing tolerance and soluble carbohydrate and proline changes of shoots during acclimation and deacclimation. LT50 values, estimated by both electrolyte leakage measurement (EL LT50) and tetrazolium stain test (TST LT50), allowed us to discriminate between the cultivars in terms of freezing tolerance. Acclimation and deacclimation did not occur simultaneously in different cultivars, having a key role in cold tolerance of cultivars, especially in fall and late winter. Post Sefid Bafgh cultivar showed high cold tolerance early in fall, but it was susceptible to cold during winter. ‘Naderi’, ‘Yusef Khani’, ‘Malas Saveh’, and ‘Robab Neyriz’ had the highest midwinter cold hardiness; ‘Mahabadi’ showed an intermediate hardiness, whereas ‘Post Sefid Bafgh’ and ‘Shishe Kap’ were found to be cold-susceptible in this period. Freezing tolerance estimated by TST corresponded to those measured by the EL method in all cultivars, but in November and January, higher variation in freezing tolerance was observed among the cultivars through TST compared with EL measurement. However, LT50 values, estimated by EL measurement, were lower than those estimated through TST in November and March. Soluble carbohydrate concentrations of stem samples increased during cold acclimation from November to January; then it decreased in March. Proline had a narrow range of variation among the cultivars in November, but an increase in the amount of proline was observed during the period of hardening. In general, stronger correlations were observed between LT50 values and the amounts of soluble carbohydrates compared with proline, particularly from fall to midwinter.
Passive Control of Downslope Capillary Wicking of Water in Sand-based Root Zones
Authors: McInnes Kevin J. , Thomas James C.
Published: February 2019

Chronic dry spots that occur on the upper reaches of slopes on golf putting greens lead to increased frequency of irrigation to maintain a healthy turfgrass surface. To limit one cause of dry spots, the downslope wicking of water, we investigated the use of subsurface barriers to interrupt the capillary connectivity of the bottom portion of the root zone on a 3.5-m long, laboratory-simulated section of a green having a 5% slope. We evaluated the effectiveness of the barriers on a green constructed with a sand root zone over gravel drainage and on a green constructed with a sand root zone over a geotextile atop a porous plastic grid for drainage. With sand over gravel, the barriers were effective at reducing downslope wicking and the consequential loss of stored water in the root zone on the slope. In the top 0.5 m of the slope, there was 24 mm more water stored in the root zone profile of the green constructed with barriers compared with that in the green constructed without barriers. With sand over geotextile atop a plastic grid, the barriers were effective at reducing wicking of water, but only when the downslope continuity of the geotextile was broken. In that case, there was 35 mm more water stored in the root zone profile at the top of the slope in the green constructed with barriers and a discontinuous geotextile compared with the greens constructed with barriers and continuous geotextile or with sand over gravel and no barriers.
Heritability of Morphological Traits in Apple Early-ripening Full-sib and Half-sib Offspring and Its Potential Use for Assisted Selection
Authors: Hajnajari Hassan , Chashnidel Bahaeddin , Vahdati Kourosh , Ebrahimi Mohsen , Nabipour Alireza , Fallahi Esmaeil
Published: February 2019

To select the superior parents for the breeding program we oriented to produce new early-ripening cultivars, we evaluated more than 60 productive and vegetative characters in 108 native and imported cultivars grown in national collection for commercial apples located in Karaj, Iran, using an apple descriptor. The germination percentage of 100,000 hybrid seeds was 7% in the first year. In the second year, only 3000 from 7000 seedlings had to pass the final screening. Use of morphological markers as an early selection technique showed high efficiency in the apple breeding program. This study was conducted to determine heritability of certain morphological traits potentially used for selection of fruit early-ripening progenies in apple (Malus ×domestica Borkh.). Morphological traits in 3- and 4-year-old seedlings from 28 half-sib and 16 full-sib families were studied in 2007 and 2008, respectively. Parent–progeny correlations were analyzed using true-to-type progenies and their relative parents, all in the juvenile phase. Significant variations were observed between parental cultivars and half-sib and full-sib progenies for most of the studied traits. Positive correlations were found between seedling height and other morphological characters. A highly significant correlation (r = 0.98) was observed between branch distance along seedling stem and number of branches. The results showed that the heritability varied among the traits, ranging from moderate to high values. A high level of heritability was found in leaf chlorophyll concentration (LCC) and seedling heights in both half-sib and full-sib families. Heritability of half-sib progenies derived from the early-ripening parents was higher than the late-ripening parents. The relatively high heritability estimates for morphological traits, particularly in early-ripening cross combinations, suggested narrow-sense heritability as a criterion for early screening. The progenies of early cultivars exhibited the maximum and minimum heritability for seedling height (0.91) and leaf length (0.56), respectively. Oppositely, in the late-ripening progenies, the maximum and minimum heritability were found in LW and TD traits (0.79 and 0.42), respectively.
Influence of Leaf-fruit Ratio and Nitrogen Rate on Fruit Characteristics, Nitrogenous Compounds, and Nonstructural Carbohydrates in Young Persimmon Trees
Authors: Choi Seong-Tae , Park Doo-Sang , Kang Seong-Mo , Kang Seong-Koo
Published: February 2019

The effects of fruit load and nitrogen (N) rate (0, 20, and 40 g N per tree) on fruit characteristics and the composition of nitrogenous compounds (e.g., amino acids and protein) and nonstructural carbohydrates in different plant tissues were determined in container-grown 5-year-old ‘Fuyu’ persimmon trees. Leaf-fruit (L/F) ratios were adjusted to either 20 (high) or 10 (low) by fruit thinning on 2 July. N was applied by fertigation as 1% (w/v) urea from 3 July to 20 Sept. The low L/F ratio decreased size and coloration of fruits, whereas increasing N rate resulted in fruits with low skin color and soluble solids but with high firmness. The high L/F ratio increased N concentrations only in 1- to 4-year-old wood and the trunk, whereas increasing N rate increased N concentrations of all tree tissues, especially of roots. The L/F ratio did not significantly affect the composition of nitrogenous compounds and carbohydrates in the tree tissues. As N rate increased, amino acid concentrations increased in all the tree parts, especially in aerial wood and roots where a three- to eightfold increase was observed between the 0- and 40-g N rates. Although not great, protein concentrations also increased with increasing N rate. Increasing N rate significantly reduced soluble sugars in fruit, trunk, and root and starch in leaf and root. The results indicated that an excessive supply of supplemental N could delay fruit maturation and reduce carbohydrate accumulations of ‘Fuyu’ trees regardless of the L/F ratios.
Sequential Postemergence Applications for the Control of Khakiweed in Bermudagrass Turf
Authors: Hephner Andrew J. , Cooper Tyler , Beck Leslie L. , Henry Gerald M.
Published: February 2019

Khakiweed (Alternanthera pungens Kunth) response to single and sequential herbicide applications was evaluated during the summer of 2009 and 2010 in Texas. No bermudagrass phytotoxicity was observed throughout the length of each trial regardless of herbicide treatment. Carfentrazone at 0.034 kg a.i./ha, metsulfuron + carfentrazone at 0.021 + 0.034 kg a.i./ha, and trifloxysulfuron + carfentrazone at 0.018 + 0.034 kg a.i./ha exhibited 74% to 85% khakiweed control 2 weeks after initial treatment (WAIT) regardless of application regime. Control with carfentrazone (0.017 kg a.i./ha) was only 63% to 65% 2 WAIT regardless of application regime. Metsulfuron and trifloxysulfuron treatments exhibited 54% or less khakiweed control 2 WAIT regardless of rate. Six weeks later (8 WAIT), sequential applications of metsulfuron exhibited 98% control regardless of rate, whereas control with single applications was 79% to 87%. Sequential applications of trifloxysulfuron exhibited 86% to 88% khakiweed control 8 WAIT regardless of rate, whereas single applications exhibited 47% or less control. Carfentrazone treatments exhibited 5% or less control regardless of rate or sequential application 8 WAIT. Tank-mixing metsulfuron or trifloxysulfuron with carfentrazone did not improve control 8 WAIT compared with either sulfonylurea herbicide applied alone. Although initial khakiweed injury was observed in all treatments, effective long-term control was difficult to achieve. Excellent control (95% to 97%) was exhibited by sequential metsulfuron applications 12 WAIT regardless of rate. Sequential applications of trifloxysulfuron (0.018 or 0.028 kg a.i./ha) and single applications of metsulfuron at 0.042 kg a.i./ha exhibited moderate khakiweed control (75% to 80%) 12 WAIT. All other treatments exhibited 57% or less khakiweed control 12 WAIT. Efficacy of sequential metsulfuron applications is a strong incentive for its adoption over trifloxysulfuron applications for the control of khakiweed in bermudagrass turf.
Kernel Necrosis of ‘Pawnee’ Pecan: Expanded Distribution and Relation to Yield, Tree Size, and Canopy Location
Authors: Smith Michael W.
Published: February 2019

Pecan [Carya illinoinensis (Wangenh.) K. Koch.] kernel necrosis is a malady characterized by development of a dark necrotic area at the basal end of the kernel. This problem is particularly severe on ‘Pawnee’ at some locations during certain years. Currently, the cause of kernel necrosis is not known. Initially, this problem appeared confined to certain cultivars in a north Texas orchard in the Red River Basin and ‘Oklahoma’ in a central Oklahoma orchard adjacent to the Deep Fork River. After El Paso, TX, producer reports of an unknown problem on ‘Pawnee’, mature nuts from orchards near El Paso, north Texas, and southern, central and northeastern Oklahoma were evaluated for kernel necrosis. Kernel necrosis was abundant on ‘Pawnee’ nuts from El Paso and southern Oklahoma, moderate at the north Texas site, and at low levels in one northeastern Oklahoma orchard. None was found in two ‘Pawnee’ orchards, one in central Oklahoma and the other in northeastern Oklahoma. In another study, yield was monitored on hedge-pruned ‘Pawnee’ pecan trees over a 5-year period to determine the relationship with kernel necrosis. The incidence of kernel necrosis was greater when yield was less. A third study sampled nuts from the lower and upper one-third of canopies from randomly selected trees varying in trunk size. Kernel necrosis frequency was similar in the upper canopy among different trunk sizes, but the incidence in the lower tree canopy decreased as trunk size increased.
Environmental and Genotypic Variation of Capsaicinoid and Flavonoid Concentrations in Habanero (Capsicum chinense) Peppers
Authors: Butcher Justin D. , Crosby Kevin M. , Yoo Kil Sun , Patil Bhimanagouda S. , Ibrahim A.M.H. , Leskovar Daniel I. , Jifon John L.
Published: February 2019

Habanero peppers have become increasingly popular in the United States for supplying unique flavors and high levels of pungency. As consumption of this product increases, development of improved cultivars with elevated phytochemicals will likely result in additional demand from consumers. This study evaluated fruit size, capsaicinoid, and flavonoid concentrations in six Habanero (Capsicum chinense) genotypes grown at three different Texas locations: College Station, Uvalde, and Weslaco. Five of these Habanero experimental hybrids (H1-red, H2-orange, H3-orange, H5-dark orange, and H6-yellow) were developed at Texas A&M University with genetic improvement in numerous traits of interest, and Kukulkan F1 (Kuk-orange) was included as a commercial control. In general, H1-red had the largest fruits in these locations. Capsaicin and dihydrocapsaicin (DHC) concentrations were highest in Kuk-orange followed closely by H5-dark orange and were lowest in H6-yellow. Fruit at Weslaco was larger and contained more capsaicin and DHC than those produced in Uvalde or College Station. Although flavonoid contents were variable and low in all genotypes and locations, H3-orange showed the most stability for use in future crossing schemes to compete against Kuk-orange for this characteristic. Our results suggest that variation in phytochemicals in fruit tissue of Habanero genotypes can be exploited by selecting in an appropriate environment.
Partial Leaf Chemical Profiles of a Desert Watermelon Species (Citrullus colocynthis) and Heirloom Watermelon Cultivars (Citrullus lanatus var. lanatus)
Authors: Ogbuji Kelechi , McCutcheon Gloria S. , Simmons Alvin M. , Snook Maurice E. , Harrison Howard F. , Levi Amnon
Published: February 2019

Whiteflies [Bemisia tabaci (Gennadius)] and aphids [Aphis gossypii Glover and Myzus persicae (Sulzer)] are serious threats to watermelon by direct feeding and by transmitting viruses of important virus diseases. The desert watermelon Citrullus colocynthis (L.) has been shown to exhibit resistance to these insect pests and could be a useful source for breeding resistance into watermelon [Citrullus lanatus var. lanatus (Thunbs) Matsum & Nakai]. Using high-performance liquid chromatography (HPLC), we found differences among the chemical profiles of two U.S. PIs of C. colocynthis, one PI of C. lanatus var. citroides, and two heirloom watermelon (C. lanatus var. lanatus) cultivars (‘Charleston Gray’ and ‘Mickey Lee’). Flavonoid and caffeic acid derivatives were identified in the leaf extracts by a combination of ultraviolet (UV) and mass spectrometry (MS) spectral analyses. Four phenolic derivatives of caffeic and/or ferulic acid were found to be essentially unique to C. colocynthis. Total flavonoid content was found to be approximately four to 18 times higher in C. colocynthis accessions and seven to nine times higher in C. lanatus var. citroides as compared with watermelon cultivars. Caffeoyl-glucose was also identified in the leaves of watermelon cultivars for the first time. Leaf sugar concentrations (198 to 211 mg·dL−1), read from a glucometer, were statistically the same among the various germplasm entries. These results will help in the development of pest-resistant watermelon.
A Novel Framework to Consider Endogenous Hormonal Control of Apple Tree Flowering
Authors: Pellerin Brian P. , Buszard Deborah , Georgallas Alex , Nowakowski Richard J.
Published: February 2019

Inhibition of flower initiation by nearby developing fruits is one of the main causes of biennial bearing in apple trees. This localized inhibition may depend on a critical ratio of inhibitor and promoter hormones that inhibits flowering of apical meristems. A model is proposed to explain this phenomenon. In the model, it is assumed that seeds and leaves act as point sources and export inhibiting and promoting hormones to apical meristems. The model assumes critical ratios of promoting and inhibiting hormones determine whether an apical meristem flowers or not and this may be a cause of biennial bearing. Thus, the spatial arrangement of shoot apical meristems on a limb is perhaps critical in determining whether meristems initiate flower clusters. This article presents a novel framework to view the hormone hypotheses of biennial bearing in apple trees and how management strategies such as flower removal could be used to achieve regular numbers of flower clusters over consecutive years.
Management of Primocane-fruiting Blackberry: Impacts on Yield, Fruiting Season, and Cane Architecture
Authors: Strik Bernadine C. , Clark John R. , Finn Chad E. , Buller Gil
Published: February 2019

Primocane management systems were compared for ‘Prime-Jan’® and ‘Prime-Jim’®, primocane-fruiting blackberry (Rubus L. subgenus Rubus, Watson), grown in a field planting in Aurora, OR. Treatments studied were: 1) no manipulation of primocanes (untipped; no floricanes); 2) untipped primocanes growing in the presence of floricanes; 3) untipped primocanes grown with rowcover in late winter to early spring; and 4) primocanes “soft-tipped” at 1 m to encourage branching. Date of primocane first bloom and cane height at bloom were unaffected by cultivar and were only affected by primocane management in 2005. The number of growing degree-days to first bloom ranged from 1272 to 1390 depending on year. Primocane management did not affect ovule or drupelet number per berry or percent drupelet set. ‘Prime-Jim’ had more drupelets and greater weight per berry in 2005 than ‘Prime-Jan’. Fruit harvested earlier in the season had more ovules and drupelets than later harvested fruit in 2004. Primocanes that grew in the presence of floricanes were longer and bloomed later but did not differ in yield from untipped canes grown only for a primocane crop. Use of rowcover in 2005 advanced bloom and harvest, improving yield 73% compared with untipped control canes. Soft-tipping primocanes increased yield 114% to 150% compared with untipped canes (5.6 vs. 2.4 t·ha−1) through increasing branch and node number per cane and percentage of fruiting nodes; soft-tipping did not delay harvest. Yield/cane was negatively correlated with the number of fruiting canes/plot but positively correlated with branches/cane, total branch and cane length, number of nodes and percent fruiting nodes, fruit/cane, and berry weight. The proportion of fruiting nodes was greater on branches than on the main cane illustrating the importance of managing this type of blackberry to increase branch number for high yield.
Rapid Rutin Accumulation during Spear Elongation in Asparagus
Authors: Motoki Satoru , Kitazawa Hiroaki , Kawabata Tomonori , Sakai Hiroaki , Matsushima Ken-ichi , Hamauzu Yasunori
Published: February 2019

Head tightness, soluble solid content (SSC), and rutin level were investigated in asparagus spears harvested at different lengths. We found no correlation between spear length and SSC per dry weight (DW) in spearheads. Spearheads became looser and the rutin content of the spearhead increased as spear length at harvest increased, although appearance quality decreased. These findings revealed that spears previously discarded, because their length did not meet the length specifications, contained abundant rutin. Therefore, spears for which the optimum harvesting time has been missed are a useful rutin source.
Response of Highbush Blueberry to Nitrogen Fertilizer During Field Establishment, I: Accumulation and Allocation of Fertilizer Nitrogen and Biomass
Authors: Bañados M. Pilar , Strik Bernadine C. , Bryla David R. , Righetti Timothy L.
Published: February 2019

The effects of nitrogen (N) fertilizer application on plant growth, N uptake, and biomass and N allocation in highbush blueberry (Vaccinium corymbosum L. ‘Bluecrop’) were determined during the first 2 years of field establishment. Plants were either grown without N fertilizer after planting (0N) or were fertilized with 50, 100, or 150 kg·ha−1 of N (50N, 100N, 150N, respectively) per year using 15N-depleted ammonium sulfate the first year (2002) and non-labeled ammonium sulfate the second year (2003) and were destructively harvested on 11 dates from Mar. 2002 to Jan. 2004. Application of 50N produced the most growth and yield among the N fertilizer treatments, whereas application of 100N and 150N reduced total plant dry weight (DW) and relative uptake of N fertilizer and resulted in 17% to 55% plant mortality. By the end of the first growing season in Oct. 2002, plants fertilized with 50N, 100N, and 150N recovered 17%, 10%, and 3% of the total N applied, respectively. The top-to-root DW ratio was 1.2, 1.6, 2.1, and 1.5 for the 0N, 50N, 100N, and 150N treatments, respectively. By Feb. 2003, 0N plants gained 1.6 g/plant of N from soil and pre-plant N sources, whereas fertilized plants accumulated only 0.9 g/plant of N from these sources and took up an average of 1.4 g/plant of N from the fertilizer. In Year 2, total N and dry matter increased from harvest to dormancy in 0N plants but decreased in N-fertilized plants. Plants grown with 0N also allocated less biomass to leaves and fruit than fertilized plants and therefore lost less DW and N during leaf abscission, pruning, and fruit harvest. Consequently, by Jan. 2004, there was little difference in DW between 0N and 50N treatments; however, as a result of lower N concentrations, 0N plants accumulated only 3.6 g/plant (9.6 kg·ha−1) of N, whereas plants fertilized with 50N accumulated 6.4 g/plant (17.8 kg·ha−1), 20% of which came from 15N fertilizer applied in 2002. Although fertilizer N applied in 2002 was diluted by non-labeled N applications the next year, total N derived from the fertilizer (NDFF) almost doubled during the second season, before post-harvest losses brought it back to the starting point.
Sensory Quality and Consumer Acceptance of ‘Tardibelle’ Peach Are Improved by Deficit Irrigation Applied During Stage II of Fruit Development
Authors: Vallverdu Xavier , Girona Joan , Echeverria Gemma , Marsal Jordi , Behboudian M. Hossein , Lopez Gerardo
Published: February 2019

Deficit irrigation (DI) applied during Stage II of fruit development has the potential of improving fruit quality in peach (Prunus persica). Existing information only covers instrumental assessment of quality. No report is available on how sensory attributes and consumer acceptance are affected. We applied DI at Stage II to ‘Tardibelle’ peach and evaluated fruit composition, sensory attributes, and consumer acceptance during the growing seasons of 2009 and 2010. Results were compared with those from trees that received conventional irrigation (CI). Stem water potential in DI trees was indicative of a moderate water stress during Stage II. In 2010, water stress persisted at the beginning of Stage III and average fruit weight was reduced in DI trees. A panel of trained judges decided that DI increased sweetness, juiciness, and the intensity of peach flavor but it reduced fruit firmness and crispness. A panel of consumers indicated increased preference for DI fruit. The higher appeal for DI fruit could have been partially the result of their more advanced maturity. Improvement of fruit quality could be an important incentive for the application of DI during Stage II because growers may expect to receive a premium price for their higher quality fruit.
Phenolic Composition of Basil Plants Is Differentially Altered by Plant Nutrient Status and Inoculation with Mycorrhizal Fungi
Authors: Scagel Carolyn F. , Lee Jungmin
Published: February 2019

Four cultivars of basil (Ocimum basilicum L. ‘Cinnamon’, ‘Siam Queen’, ‘Sweet Dani’, and ‘Red Rubin’) were inoculated or not with the arbuscular mycorrhizal fungus (AMF), Rhizophagus (formerly Glomus) intraradices (Schenck & Smith) Walker & Schüßler and grown with a fertilizer containing either 64 mg·L−1 phosphorus (P) (low P) or 128 mg·L−1 P (high P) to assess whether 1) P availability and inoculation with AMF influences the phenolic composition of basil; and 2) treatment effects on phenolic composition are related to plant nutrient status. Growth, root colonization by AMF, anthocyanins, total phenolics, specific polyphenolics, and mineral nutrients were measured after 16 weeks of growth. Non-inoculated plants were not colonized by AMF. AMF colonization of inoculated plants was not influenced by P rate. Increased P rate and AMF inoculation increased biomass. Increased P rate enhanced (increased concentration and content) P and calcium (Ca) uptake and AMF inoculation enhanced nitrogen (N), potassium (K), sulfur (S), boron (B), iron (Fe), and zinc (Zn) uptake. Increased or decreased uptake (content) of other nutrients between P rates and AMF treatments were related to differences in biomass (e.g., similar or lower concentration). Treatment effects on phenolic accumulation were related to the effects of P rate and AMF on 1) plant growth; 2) nutrient uptake; and 3) other factors not directly related to measured differences in nutrient uptake or plant growth. Differences between treatments in rosmarinic acid, the predominant polyphenolic produced by all cultivars, were related to the effects of P rate and AMF on plant growth. Both increased P rate and AMF inoculation enhanced production (increased concentration and content) of chicoric acid and caffeic acid derivative. Increased P rate and inoculation with AMF differentially enhanced production of several other minor polyphenolics resulting in plants with different polyphenolic profiles. Results indicate that AMF inoculation may be an additional strategy for optimizing basil quality in terms of polyphenolic production and composition beyond benefits obtained from just altering plant nutrient status or selecting specific cultivars.
Developing Phloem δ13C and Sugar Composition as Indicators of Water Deficit in Lupinus angustifolius
Authors: Merchant Andrew
Published: February 2019

The use of naturally occurring carbon isotope ratios (expressed as δ13C) obtained from phloem sap offers considerable promise for evaluations of short-term physiological status of plants. We investigate the suitability of δ13C among carbon pools isolated from both leaves and phloem sap as surrogate measures of plant gas exchange in Lupinus angustifolius L. We also investigate the use of phloem osmotic potential (ψS), and metabolite concentrations as surrogate measures of δ13C. Phloem sap carbon bled from the distal tip of the fruit offers considerably improved correlations between δ13C and plant gas exchange compared with δ13C of carbon pools obtained from extractions of excised phloem tissue and leaf soluble carbon. The concentration of phloem sugars and sugar alcohols correlates strongly with measures of phloem δ13C but not with phloem ψS. We discuss these results in the context of developing fast, reliable, in-field tools for the assessment of plant physiological status.
Infrared and Chlorophyll Fluorescence Imaging Methods for Stress Evaluation
Authors: Glenn D. Michael
Published: February 2019

Infrared and chlorophyll fluorescence imaging methods are useful techniques to evaluate environmental effects on plant performance. With the advent of digital imaging and advances in sensor technology, infrared (IR) thermography has become more accurate and less expensive. Modern IR cameras can resolve 0.5 °C temperature differences and research-grade instruments can resolve 0.05 °C. This precision has allowed the physical processes of freezing and transpiration to be more accurately studied and modeled. Chlorophyll fluorescence imaging, although still an expensive technology, has also become sufficiently rugged to be useful in the field. The measurement of quantum efficiency, Fv/Fm, provides clear data on the effect of various environmental and biotic effects on the performance of photosynthesis in plants through the effect on photosystem II. Modern digital cameras with low signal-to-noise ratios can also image chlorophyll fluorescence using time lapse exposure. Peltier-cooled charge coupled device (CCD) cameras can measure the autoluminescence in stressed plants that is generated by reactive oxygen species. Advances in technology have reduced the cost and precision of imaging equipment to a point that they are more applicable tools to plant scientists.
Tolerance to Fusarium Root Rot and the Changes in Free Amino Acid Contents in Mycorrhizal Asparagus Plants
Authors: Okada Tomohiro , Matsubara Yoh-ichi
Published: February 2019

Tolerance to fusarium root rot and the changes in free amino acid contents in mycorrhizal asparagus (Asparagus officinalis L., cv. Welcome) plants were investigated. Sixteen weeks after inoculation of arbuscular mycorrhizal fungus (AMF; Glomus sp. R10), mycorrhizal plants showed higher dry weight of ferns and roots than non-mycorrhizal plants, and AMF colonization level in a root system reached up to 73.3%. Ten weeks after Fusarium oxysporum f. sp. asparagi (Foa; MAFF305556, SUF1226) inoculation, disease incidence and the severity of symptoms were eased and disease indices were low as less than 20 in mycorrhizal plants compared with non-AMF plants in the both isolates. As for the changes in free amino acid, total free amino acid contents in ferns and roots were higher in AMF plants than non-AMF plants 16 weeks after AMF inoculation. In this case, eight constituents of amino acids in ferns and 16 in roots increased in AMF plants; in particular, arginine and gamma-aminobutyric acid (GABA) showed considerable increase in both ferns and roots in AMF plants. In the Foa culture by Czapec-Dox medium in vitro, suppression of Foa propagation was recognized by the addition (0.1, 1%, w/v) of arginine and GABA. From these findings, plant growth enhancement and tolerance to fusarium root rot occurred in mycorrhizal asparagus plants, and the disease tolerance was supposed to be associated with the symbiosis-specific increase in free amino acids.
Indigenous Asian Specialty Vegetables in the Central Valley of California
Authors: Molinar Richard H.
Published: February 2019

Sinqua and moqua, better known as Luffa actuangula and Benincasa hispida var. chiehgua, are but a few of the 70 or so Asian vegetables being grown in Fresno, CA. These little-known vegetables are very common to the 1300 Hmong, Mien, Lao, and Chinese farmers growing them for the specialty and wholesale markets in Fresno. This article discusses 24 Asian vegetables commonly grown on farms and sold to more than a dozen specialty crop packing houses in Fresno and at farmers markets in California. Cultural information, pest problems, and culinary uses are also briefly discussed.
Patterns of Fructose, Glucose, and Sucrose Accumulation in Snap and Dry Bean (Phaseolus vulgaris) Pods
Authors: VandenLangenberg Kyle M. , Bethke Paul C. , Nienhuis James
Published: February 2019

Sugars, including fructose, glucose, and sucrose, contribute significantly to the flavor and consumer acceptance of snap beans (Phaseolus vulgaris L.). Little is known regarding differences in sugar content among snap bean and dry bean cultivars and the patterns of sugar accumulation with increasing pod size. Alcohol–soluble sugar concentration of five snap bean cultivars and one dry bean cultivar planted in field trials was assayed throughout pod development over 2 years using high-performance liquid chromatography. Significant differences in sugar accumulation patterns and quantity were observed among cultivars. In general, fructose and glucose content decreased, whereas sucrose increased with increasing pod size in snap beans. In contrast, fructose and glucose amounts increased, whereas sucrose concentration remained unchanged with increasing pod size in the dry bean cultivar. No year-by-genotype interactions were observed for sugar accumulation patterns or sugar amount. Results indicate that sieve size No. 3 (7.34 to 8.33 mm) or No. 4 (8.33 to 9.52 mm) pods are suitable for detecting differences in sugar concentration among genotypes.
Nitrogen Rates Effects on the Yield, Nutritional Status, Fruit Quality, and Profitability of Tomato Grown in the Spring with Subsurface Irrigation
Authors: Ozores-Hampton Monica , Simonne Eric , Roka Fritz , Morgan Kelly , Sargent Steven , Snodgrass Crystal , McAvoy Eugene
Published: February 2019

With increasing environmental concerns, the sharp cost increase of fertilizer and the absence of a soil test to predict nitrogen (N) needs of tomato (Solanum lycopersicon L.) grown on Florida’s sandy soils, a partnership was created with growers, state agencies, and the University of Florida, Institution of Food and Agricultural Sciences (UF/IFAS). The objectives of this study were to identify a range of N rates that would result in highest yields and postharvest quality, and maximum economical return for tomato, grown with subsurface irrigation (management of a perched water table above an impermeable soil layer or hard pan) during the spring season (low probability of leaching rain events). The study was conducted in Spring 2007 and 2008 in Palmetto, FL, with N rates ranging from 22 to 470 kg·ha−1 at pre-plant as ammonium nitrate (NH4NO3). Weather conditions were typical of a dry spring season in central Florida with no leaching rain events recorded in either year; however, rain patterns were different between the 2 years. In the absence of leaching rain and frost protection (either may raise the water table), petiole sap NO3-N decreased over time and the rate of decline depended on the N fertilizer rate. Extra-large and total marketable fruits yields showed a quadratic plateau response to N rates with maximum yields at two harvests (97% of the yields) grown with 172 and 298 kg N/ha in 2007 and 2008, respectively. During subsequent ripening, N rate did not correlate consistently to fruit ripening rate, fruit firmness, nor compositional quality at table-ripe stage. The high value of tomatoes relative to the cost of N fertilizer created a situation in which the profit-maximizing rate of N was not significantly different from the production-maximizing N rate. Whether the profit-maximizing level of N was higher or lower than the UF/IFAS-recommended rate depended on the growing season. With favorable growing conditions (i.e., conditions in 2008), a grower’s net return would have decreased between $1000 and $2000 per hectare by using UF/IFAS-recommended rates depending on market conditions. However, if the UF/IFAS-recommended rate of 224 kg·ha−1 resulted in the highest yield, applying upwards of 300 kg·ha−1 would have increased grower production costs by at least $67/ha. Although fertilizer costs are known before the crop is grown, tomato prices are realized only at the end of the growing season and profit margins can only be calculated after the fact.
Responsible Use of Medicinal Plants for Cosmetics
Authors: Schmidt Barbara M.
Published: February 2019

Medicinal plant extracts are widely used as active ingredients in cosmetics. Plant material can come from a variety of sources, including commercial production horticulture and wild harvest in developing countries. Sustainably produced plant material does not threaten biodiversity, release pollution, compete with the food supply, or exploit local people. International treaties like the Rio Convention on Biological Diversity and CITES (Washington Convention) and regulations like Good Agricultural Practices (GAP) have been established to guide sustainable sourcing and production of plant material. Non-profit organizations like the Round Table Sustainable Palm Oil have been organized to create sustainability standards. Once a reliable and sustainable supply chain has been established, cosmetic companies must be aware of regulations set by the U.S. Food and Drug Administration, U.S. Department of Agriculture, and international regulatory agencies that guide the marketing of cosmetics with medicinal plant ingredients. Efficacy claims should be supported with evidence and cannot state that the product treats medical conditions. In the end, responsibly sourced medicinal plants can bring economic benefit to producers, processors, and marketers.
Impact of Drought Stress on the Accumulation of Capsaicinoids in Capsicum Cultivars with Different Initial Capsaicinoid Levels
Authors: Phimchan Paongpetch , Techawongstien Suchila , Chanthai Saksit , Bosland Paul W.
Published: February 2019

Capsaicinoids are the alkaloids in hot pepper that cause the sensation of heat when eaten and are affected by a genetic and environment interaction. Drought stress is well recognized as an environmental condition that influences capsaicinoid accumulation. This investigation identified the responses of capsaicinoid accumulation in hot pepper cultivars under drought stress condition. A total of nine cultivars with a different initial pungency level, i.e., low, medium, and high, was subjected to gradual drought stress during the flowering stage. Plants in this drought stress group were supplied with reduced water applications of 25%, 50%, and 75% by volume at 10, 20, and 30 days after flowering (DAF), respectively. Leaf water potential and relative water content were recorded to measure the level of drought stress. The results indicated that all cultivars were subjected to drought stress because of their decrease in leaf water potential and changes in physiological characteristics, e.g., growth and yield performance. In addition, leaf area and shoot-to-root ratio were good criteria for identifying hot pepper cultivars under drought stress because their responses were correlated with the stress level and yield components. Yield performances of the high pungency group did not decrease under drought stress, whereas those of the low pungency group did decrease. In conclusion, capsaicinoid levels increased for all cultivars studied when subjected to drought stress, except for the cultivars in the high pungency group. A yield response under drought stress for the medium pungency group varied and was not found to be associated with drought stress.