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The objective of this two-year study was to assess the effect of N source on plant physiology, yield and fruit quality of apricot (Prunus armeniaca ‘Mogador’) trees. Parameters evaluated included: ...

Seventy melon (Cucumis melo L.) accessions comprising of landraces, inbred lines, cultivars, wild relatives and exotic populations were characterized using fifteen fruit traits and 30 SSR markers. Overall, aim of this study was to investigate the genetic relatedness across origins, horticultural groups and accession categories. Significant differences were observed for days to first fruit maturity, fruit weight, fruits per vine, yield per plant, flesh thickness, fruit shape index, total soluble solids, β-carotene, ascorbic acid and titrable acidity. Twenty-four polymorphic SSRs detected 67 distinct alleles with moderate polymorphic information content (0.43) and genetic diversity (0.44). Observed heterozygosity (0.53) was higher than expected heterozygosity (0.48) which can be attributed to out-cross nature of melons. Neighbor joining tree based on SSRs diverged 70 accessions into six clusters independent of geographic sites of collections. Momordica and inodorus accessions formed distinct clusters, with some exceptions. Intermixing of landraces, modern cultivars and exotic accessions belonging to different taxa and geographic regions indicated genetic resemblance with each other. Hybridization among exotic and indigenous genetic resources can be utilized for genetic enhancement and introgression of new traits in modern melon cultivars. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12298-020-00814-1) contains supplementary material, which is available to authorized users.

Soil organic matter degradation and water limitation caused by intense farming activities are some of the major threats affecting agricultural production. Accordingly, the concepts of sustainable agricultural systems with optimized irrigation and improved soil quality can be adapted to address these issues. During this 2-year field study, two management factors—humic substances (HS) as organic inputs (HS vs. control) and deficit irrigation as the irrigation method (50% vs. 100% based on evapotranspiration)—were evaluated based on triploid watermelon (Citrullus lanatus cv. Fascination) yield and soil property changes. HS application increased watermelon early yield by 38.6% and total yield by 11.8% compared with the control; the early yield mainly increased under deficit irrigation. Compared with full irrigation, deficit irrigation increased water use efficiency (WUE) without significantly affecting total yield. In addition, HS application significantly increased the soil organic carbon (SOC) content, which was found to be positively correlated with crop WUE. These results indicate that soil organic inputs with HS and deficit irrigation are valuable strategies to establish sustainable systems for watermelon production, which will not only increase yield and WUE but also significantly improve soil quality and save irrigation water.

The stability of yield and quality traits in nine orange-fleshed melon (Cucumis melo L.) genotypes was studied over nine environments in south-central Texas (College Station, Uvalde, and Weslaco) over 3 years (2010, 2011, and 2012). Besides yield traits, fruit -quality components such as soluble solids content (SSC), β-carotene, and fruit firmness were also measured. Data were subjected to the combined analysis of variance and trait stability by GGE Biplot. The significant genotype-by-location interactions for yield traits demonstrated the potential to develop location-specific cultivars. However, the temporal fluctuations in productivity emphasized the need to select for stability over several years in potential cultivars for the target environments. Cultivar Mission was confirmed as the most stable and average performing genotype for marketable yield and quality traits at all locations. Uvalde was identified as the ideal location for selecting generally adapted genotypes for south-central Texas. Biplot analysis indicated that Orange Dew was the highest mean performing genotype for SSC. The hybrid Oro Duro, followed by TAMU 146, ranked highest for mean and stability of β-carotene content, but it ranked lowest for fruit firmness. TAMU Orange Casaba exhibited specific adaptation, producing the highest mean fruit yield at Weslaco, while Journey had the highest fruit yield at College Station and Uvalde. Understanding of genotype-by-environment interactions for multiple traits in melon is critical for developing cultivars with high mean performance and stability in target growing environments.

Background: Carbon (δ13C) and nitrogen (δ15N) isotope ratios of collagen from teeth and bone are used to study human nutrition and health. As bones are constantly remodelling throughout life, isotopic values of bone collagen represent an average of several years. In contrast, human teeth do not remodel and their primary dentine contains only the isotopic data from the time of formation. In contrast to all other bones, human auditory ossicles also appear not to remodel. As they develop in utero and finish formation in the first 2 years of life, their collagen should also represent isotopic values of these two relatively short periods.Aim: By comparing δ13C and δ15N data from ossicles and incremental dentine, this study aims to investigate how two developmental periods of the ossicles, in utero and the first 2 years of life, reflect in collagen obtained from the ossicles.Subject and methods: Ossicle and tooth samples of 12 individuals aged 0.5 ± 0.4 years to 13 ± 1 years from the nineteenth century St. Peter's burial ground in Blackburn were collected and processed to obtain bulk bone and incremental dentine collagen which was measured for δ13C and δ15N.Results: Averaged δ13C and δ15N of ossicles are lower when compared to every age group except after 3 years of age. Average offset between ossicles and dentine of different groups ranges from 0.4-0.9‰ for δ13C and from 0.3-0.9‰ for δ15N, with highest counterbalance at birth and after the first 5 months after birth.Conclusions: There appears to be a systematic offset between the dentine and ossicle data. It seems that the second phase of development does not influence the isotopic values of collagen significantly and the data we are obtaining from ossicles represents the in utero period.

Nitrogen (N) status in olive trees is critical to develop several developmental mechanisms that control shoot, root and nutrient uptake capacity. The objective of this field study was to assess the effect of N level and form on root growth dynamics, shoot growth, leaf-level gas exchange [photosynthesis (Pn), transpiration (E), and stomatal conductance (gs)] and leaf nutrient content of young olive (Olea europaea cv. Arbequina) trees. Olive cuttings were planted in the field and grown for two years (2015, 2016). In both years, cuttings were subjected to 7 N treatments: control (no N), nitrate (NO3−) form applied as calcium nitrate (CN) at 20, 40 and 60 kg ha-1, and ammonium (NH4+) applied as urea at 20, 40 and 60 kg ha-1. Minirhizotron image analysis showed that the application of N significantly reduced root length intensity (La, mm cm-2) compared to control olives in both years. No significant difference was noticed between N forms for La in 2015. However, CN treatment had higher La than urea in April and June 2016. In addition, the overall mean of La across the study period (2015–2016) showed that La in the lower soil depths, 40–60 and 60–80 cm was significantly higher than those from the top layers, 0–20 and 20–40 cm. Unfertilized (control) cuttings had also higher tree height, stem diameter and branch number than olives that received 40 or 60 kg ha-1-N across the study period (2015-2016). In both years, leaf N% in control olives was above the N deficiency thresholds; i.e. 2.1% in 2015 and 2.57% in 2016. However, leaf mineral concentrations were inconsistent (P, Ca+2, Na, Zn, Fe, Cu) or not significant (Mn, S and B). In addition, no significant difference was noticed between treatments in gas exchange (Pn, gs and E). Overall, untreated-control young olive trees showed consistently higher La and shoot growth than N-treated trees (CN and urea) over the study period 2015-2016. Therefore, N application is not needed if leaf N levels are normal during the previous season. In fact, high rates of N in the soil during establishment of young olive trees can negatively affect root and shoot growth.

Leaf gas exchange and growth responses of three melon cultivars, i.e., Mission, Da Vinci (var. reticulatus), and Super Nectar (var. inodorus) to two irrigation regimes, 50 and 100% crop evapotranspiration (ETc) were investigated under water-limited conditions of southwest Texas. In 2012, deficit irrigation (50% ETc) significantly decreased above-ground biomass, leaf area, leaf number, and specific leaf area, while leaf gas exchange, relative water content, water potential, chlorophyll fluorescence (Fv/Fm), and chlorophyll content (SPAD index) were not affected. However, in the drier year 2011, deficit irrigation significantly reduced net photosynthetic rate (PN) and stomatal conductance (gs). Further, the responses to water deficit varied with cultivars. At 50% ETc, PN and gs were maintained in cv. Da Vinci while decreased in Mission and Super Nectar. Thus, the late maturing cv. Super Nectar appeared to be more sensitive to drought stress, possibly due to the decrease in leaf area and PN.

Diesel fuels have an essential function in industrial economies. In the last decade, several studies were conducted in order to find alternative sources of vegetables oils suitable to biodiesel conversion. The present work aimed to characterize the oil chemical composition in eleven different accessions of domestic and wild cardoon (Cynara cardunculus L. var. altilis and var. sylvestris, respectively) in order to evaluate its putative use as an alternative energy crop, with main focus in biodiesel production. No significant differences were measured between both botanical varieties for oil content; values of 20.80 ± 6.65% were found. The highest values were observed for the wild cardoon accessions “Uruguay Centro” (35.95%) and “Pergamino” (27.78%). The fatty acid composition was similar for both botanical varieties: palmitic (10.9%), stearic (3.0%), oleic (23.5%) and linoleic (61.3%). Comparing with traditional energy crops (soybean, sunflower and rapeseed) the cardoon fatty acid profile is similar to those obtained for soybean. Several biodiesel quality parameters were calculated or estimated over different oil samples. In this way, the acidity ranged from 0.1 to 0.7 mg OH/goil, showing differences among accessions but not between botanical varieties. “Cardo Blanco Peralta” and A-41 (cultivated cardoon) presented the lowest unsaturated degree, iodine values and oleic/linoleic acid relation in their oil; consequently, they showed the most suitable values for the biodiesel quality parameters (cetane number and kinetic viscosity). Based on seed oil composition, this characterization, allowed demonstrating that cardoon oil has appropriate characteristics to be used as feedstock for the production of biodiesel, as well as, to detect accessions with superior quality properties. Fil: Mancini, Micaela. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario; Argentina Fil: Lanza Volpe, Melisa. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Mendoza-San Juan. Estación Experimental Agropecuaria Mendoza. Laboratorio de Fitovirología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Gatti, María Bernardita. Universidad del Centro Educativo Latinoamericano; Argentina Fil: Malik, Yair Fernando. Universidad del Centro Educativo Latinoamericano; Argentina Fil: Morero, Ana Carina. Universidad del Centro Educativo Latinoamericano; Argentina Fil: Leskovar, Daniel Ivan. Texas A&M Agrilife Research Center; Estados Unidos Fil: Cravero, Vanina Pamela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; Argentina

The objective of this two-year field study was to assess the influence of stand establishment methods (direct seeding or transplanting) on root growth dynamics, shoot morphology, leaf physiology, yield, and quality of globe artichoke (Cynara cardunculus). Three artichoke cultivars were evaluated, ‘Green Globe Improved’ (GGI), ‘Imperial Star’ (IS), and ‘Romolo’ (ROM). Plants established with the transplanting method had higher mean root length intensity (La), root length, and root surface area as compared to plants established by direct seeding. The topsoil (0–20 cm) had on average higher La, root length, and root surface area than deeper soil profiles. Transplanted plants had higher plant shoot width and leaf area index (LAI) chlorophyll content index (SPAD) than direct seeded plants at the vegetative stage in 2015. The improvement of root and shoot growth in transplants (compared to direct seeding) also resulted in higher (p &lt, 0.05) marketable yield (21.1 vs. 19.9 ton ha−1 in 2015 and 18.3 vs. 13.7 ton ha−1 in 2016). Additionally, 46–50% of the total yield occurred during the first 30 days of harvest in the transplanting method compared to 13–38% for direct seeding. No significant differences were found between planting methods or cultivars in leaf-level gas exchange (photosynthesis, stomatal conductance, and transpiration) and cynarin concentration in the marketable heads. Although chlorogenic acid was similar in both establishment methods in 2015, direct seeding had higher concentration in 2016. Comparing cultivars, GGI had higher root length, surface area, root volume, and earlier and higher marketable yield than ROM. However, ROM had higher mean root length intensity (La, total root length per specific area in soil profile) than GGI in both growing seasons. This study showed significant and consistent improvements in root and shoot traits, and yield for transplants as compared to direct seeded plants.

Texas tomato production is vulnerable to extreme heat in the spring-summer cropping period, which is exacerbated by the lack of superior genetic materials that can perform well in such environments. There is a dire need for selecting superior varieties that can adapt to warm environments and exhibit high yield stability under heat stress conditions. This research aimed at identifying heat-tolerant varieties under heat-stress conditions in controlled and open-field environments and was carried out in three stages. For the first experiment, 43 varieties were screened based on yield responses in natural open-field environment. From those, 18 varieties were chosen and exposed to control (greenhouse: 26/20 °C) and constant heat-stress (growth-chamber: 34/24 °C) conditions for three months. Measurements were done for chlorophyll fluorescence, chlorophyll content (SPAD), plant height, stem diameter and heat injury index (HII). The last experiment was conducted in an open field with a pool of varieties selected from the first and second experiments. Leaf gas exchange, leaf temperature, chlorophyll fluorescence, SPAD value, electrolyte leakage, heat injury index and yield were assessed. From the combined studies, we concluded that heat-tolerant genotypes selected by using chlorophyll fluorescence and HII in controlled heat-stress conditions also exhibited heat-tolerance in open-field environments. Electrolyte leakage and HII best distinguished tomato varieties in open-field environments as plants with low electrolyte leakage and HII had higher total yield. 'Heat Master,' 'New Girl,' 'HM-1823,' 'Rally,' 'Valley Girl,' 'Celebrity,' and 'Tribeca' were identified as high heat-tolerant varieties. Through trait correlation analysis we provide a better understanding of which traits could be useful for screening and breeding other heat-tolerant tomato varieties.

a loose/broken stalagmite containing small fragments of cemented bones were collected from the Postojna Cave to investigate whether deoxyribonucleic acid (DNA) can be determined. The study is complemented by the Fourier-transform infrared spectroscopy - attenuated total reflectance (FTIR-ATR) analysis in order to determine the alteration of the bones and to test whether this analysis can be used as an indicator of possible DNA preservation. In addition, geochemical analyses were conducted in order to determine whether the associated flowstone/stalagmite is suitable for elucidating the timing of bone thanatocoenosis and further palaeoenvironmental analyses. The organic matter (collagen) is poorly preserved. However, we succeeded in amplifying a 94 bp long fragment of the cytochrome b (Cyt b) gene of mitochondrial DNA (mtDNA) in polymerase chain reaction (PCR) for one sample, and in sequencing the amto that of the Cyt b of the cave bear (Ursus deningeri or Ursus spelaeus sensu lato). The uranium-thorium dating of the speleothem covering the bones revealed its thanatocoenosis occurred prior to 55 ka, most likely in the late marine isotope stage 4 or early marine isotope stage 3. High porosity and recrystallisation of the flowstone/stalagmite at this part of the cave prevent high-resolution palaeoclimatic interpretation; however, low-resolution stable isotope geochemistry suggests a steppe-like environment during the subsequent growth of the speleothem.

The sensory and functional quality attributes of muskmelons (Cucumis melo L.), such as flavor, sweetness, color, and texture, determine consumer preferences. Genetic makeup primarily regulates these traits, but environmental factors such as soil type, irrigation, and temperature affects yields and quality. Here, we investigated variation in quality traits of diverse melon cultigens (advanced breeding lines or cultigen) grown in multiple locations (California, Texas, Georgia, Arizona, and North Carolina) across the United States. Mesocarp sugar and carotenoid concentrations varied significantly as a function of production location and cultigen. Multivariate analyses revealed significant cultigen, location, and interactive effects on fruit quality. The highest sugar content was found in a honeydew melon cultigen (HD-150; 83.1 ± 2.36 mg/g) grown in Georgia and the Western Shipper type cantaloupe (F-39; 70.8 ± 2.85 mg/g) grown in North Carolina compared to the other cultigens. The Tuscan type (Da Vinci) grown in Texas and Georgia had the highest β-carotene concentrations (29.1 ± 3.37 and 33.6 ± 1.73 µg/g, respectively) compared to the other cultigens. These observations, showing that cultivar and location significantly influenced melon phytochemical composition, will help melon breeding programs improve the sensory and functional qualities of melons and identify suitable cultivars for specific environments to maximize fruit quality.

Multiplicative Effects of Sport on Young People Involved in Sports Activities. Through a critical review of secondary literature sources, the involved experts prepared through mutual acquaintance, search for specific competencies of individuals and combining knowledge a synthesis of the field of sport among young people and the identification of multiplicative effects of sport on young people involved in sports activities. The cooperation was supported throughout the time by the Skofja Loka Sports Institute, which acts as a partner and on the basis of which a case study was built. During the research, through interviews and validation of experts (coaches, current and former athletes), a qualitative research was conducted on the quality of the findings and the proposed curriculums for the implementation of planned activities. An information solution on the Moodle platform has also been prepared.

Information on root growth patterns is crucial to understand cultivar adaptations to deficit irrigation, particularly for subsurface drip-irrigated crops, where root systems are more confined than furrow or sprinkler systems. A 2-year field experiment evaluated the effect of deficit irrigation (50% vs. 100% crop evapotranspiration, ETc) on root growth of melon (Cucumis melo L.) cultivars (Mission, Da Vinci, and Super Nectar) on a mollisol soil in southwestern Texas, USA. Root length intensity (La; mm cm−2), and root length density (RLD; cm cm−3) were measured at different growth stages using the minirhizotron and soil core methods, respectively. A higher La was recorded in 2012 than in 2011 (3.71 mm cm−2 vs. 0.50 mm cm−2), due to differences in temporal distribution of rainfall between years. Overall, deficit irrigation increased La as compared to 100% ETc, but significant effects occurred at depth (> 40 cm below the soil surface and > 25 cm below the subsurface drip tape). In 2012, moderate water deficit promoted deep root growth at the fruit setting stage but not in 2011, while root growth responses to cumulative deficit varied with cultivar. In 2012, deficit irrigation enhanced root growth in cv. Mission (cantaloupe; reticulatus) throughout the season, it was maintained in cv. Da Vinci (Tuscan; reticulatus), while it decreased in cv. Super Nectar (honeydew; inodorus) at the final harvest stage. Thus, the reticulatus melon cvs. Mission and Da Vinci can better adjust to moderate water-deficit conditions as compared to the inodorus melon cv. Super Nectar. Minirhizotron data provided useful information on root growth dynamics in deeper soil layers in a non-destructive way, which makes it a valuable tool in screening cultivars for water deficit adaptation.

The ethylene inhibitor 1-methylcyclopropene (1-MCP) is commonly used to increase the shelf life of fruits. However, the application of 1-MCP to modulate the shoot growth of vegetable transplants is unknown. The objective of this study was to assess the influence of 1-MCP on improving the growth and quality of tomato transplants. Eight tomato cultivars ('Florida 47', 'Shanty', 'Volante', 'Tycoon', 'TAMU-Hot', 'Felicity', 'Charger', and 'BHN685') were grown in greenhouse conditions for seven weeks and then 1-MCP (50 mg L-1) was applied to transplants using a boom fertigation system. After treatments, both the 1-MCP and untreated plants were transferred to 0.5-L pots and placed in three growth chamber environments differing in day/night temperature regimes, 30/20°C (optimum), 34/24°C constant (stress) and 34/24°C ramping (stress). The plant morphology and physiology variables were collected during the study period. 1-MCP application significantly increased the leaf area, stem diameter and plant height of 'Florida 47' across all temperature regimes. 'TAMU-Hot', which was grown only in the 34/24 environment (ramping) also positively responded to 1-MCP. However, the leaf gas exchange (photosynthetic rate and stomatal conductance) and SPAD measurements were inconsistent across cultivars. 1-MCP had no negative effect on the transplant growth across all cultivars in the 30/20 environment but reduced growth components in Felicity and Tycoon in the 34/24 environment. Our results showed that the application of 1-MCP to improve the transplant quality is promising. Since genetics and environment may influence the sensitivity of tomato plants to 1-MCP, future studies should aim to identify the optimal microclimate growth conditions for specific cultivars.

The objective of this study was to assess the influence of plant- and animal-based soil amendments on soil nutrient availability, CO2 respiration, yield and phytochemicals of artichoke (Cynara cardunculus cv. 179) heads. Four certified organic fertilisers: fish meal, blood meal, alfalfa meal and chicken manure, were used as experimental treatments. After two years of organic soil amended with the plant-based fertiliser (alfalfa meal), soil respiration and content of organic matter (OM) was higher than that in soil amended with animal-based fertilisers (fish meal, blood meal, and chicken manure), though the difference in OM between alfalfa and chicken manure was not statistically significant. The marketable yield from soil amended with chicken manure was higher than that amended with alfalfa meal and in the first year (2015) yields from both chicken manure and fish meal treatments were higher than that of the alfalfa treatment. Concentrations of phytochemicals in artichoke heads grown in soil amend...

Immersion treatment of a new 1-methylcyclopropene (1-MCP) formulation has shown beneficial effects on post-harvest quality retention of several fruit commodities. We examined the effects of 1-MCP concentration (0.1–10 mg/L) and immersion time (0.5–5 min) on the shelf-life of muskmelon (Cucumis melo L. var. reticulatus L. Naud) fruit. Regardless of ripening stage at harvest or storage temperature, 1-MCP immersion improved the retention of firmness and soluble solids content, while delaying the development of undesirable quality attributes, including overripe skin color, sunken discoloration area, and overripe flavor. The efficiency of 1-MCP increased with increasing concentration and immersion time, although at 10 mg/L, efficiency was maximized with as little as a 30-s immersion. Importantly, no undesirable side-effects were detected. These results suggest that 1-MCP immersion is an effective method for extending the shelf-life of muskmelon fruit. Furthermore, this technique requires only a quick dip, which is desirable for commercial implementation.

Onions (Allium cepa L.) are easily outcompeted by weeds because of slow germination and relative growth rates. Therefore, high percentage of seed germination and root vigor are important traits to improve field performance. The effects of exogenous plant growth regulators (PGRs), 2-chloroethylphosphonic acid (ethephon, Eth), indole-3-acetic acid (IAA), trans-zeatin (tZ), and 1-aminocyclopropane-1-carboxylic acid (ACC) were evaluated on the germination and root growth of ‘Don Victor’ (yellow) and ‘Lambada’ (red) onion seedlings. Seeds were soaked for 10 hours in hormonal solutions and water (hydro-priming). Seed germination improved with Eth (30 and 100 μm), Eth (100 μm) + IAA (10 μm), and IAA (3 μm) treatments. Root surface area (RSA) increased in response to Eth at 30 and 100 μm, Eth + IAA, and 3 μm IAA. Root length (RL) and root diameter (RD) were enhanced by 1 μm tZ and 100 μm ACC. Eth reduced RL and RD, whereas IAA showed no effects. A subsequent experiment evaluated synergistic effects of different PGRs. Treatment of seeds with ACC (250 μm) + tZ (0.5 μm) and ACC (250 μm) + tZ (0.5 μm) + Eth (20 μm) enhanced RL and RD. RSA was unaffected by ACC + tZ + Eth. The results suggest that exogenous PGRs could be useful to enhance germination, RL, and RSA of onion seedlings.

Grafting using suitable rootstocks mitigates the adverse effects caused by environmental stresses such as water deficit in the tomato crop. Solanum pennellii and Solanum peruvianum, the wild relatives of tomato, are used as rootstocks due to their tolerance to water deficit and soil-borne diseases. This study focused on evaluating physiological and biochemical responses of tomato plants grafted onto S. pennellii and S. peruvianum rootstocks during water deficit. The commercial tomato cultivar ‘HM 1823’ (HM) either self-grafted (HM/HM) or grafted onto S. pennellii (HM/PN), S. peruvianum (HM/PR), and ‘Multifort’ (HM/MU) rootstocks were subjected to water-deficit stress by withholding irrigation for eight days. The performance of the grafted plants under water deficit was evaluated using physiological and biochemical parameters in vegetative tissues of the grafted plants. Plants grafted using S. pennellii (PN) and S. peruvianum (PR) rootstocks showed higher values of water potential (Ψw), relative water content (RWC), net photosynthetic rate (A), and leaf water use efficiencies (WUE) compared to HM, HM/HM, and HM/MU. Plants grafted onto tomato wild relatives showed the lowest malondialdehyde (MDA) and proline content. This study demonstrated that the rootstocks of wild tomato relatives reduced the effect of water deficit to a greater extent through better physiological, metabolic, and biochemical adjustments than self-grafting plants.

Watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] and melon (Cucumis melo L.) are popular annual fruit crops of the gourd family Cucurbitaceae, drawing from discrete botanical backgrounds. For both these dessert fruits, quality is what mainly influences consumer behavior and formulates recurring purchasing habits and brand loyalty within reasonable cost. The current review examines the configuration of sensorial quality attributes during development and ripening, as compounded by highly coordinated growth and differentiation processes of various fruit tissues associated with differential expression of stage-specific genes, which affect flavor, aroma, color and texture. The genotypic effect on fruit quality is examined, which in the case of sweet melon is ramified into varietal groups demonstrating differential ripening physiology of climacteric or non-climacteric nature with important implications for key sensorial characteristics, especially aroma and texture. Current advances on the role of key agronomic factors influential on quality are discussed, such as grafting and rootstock-scion interaction, controlled water and thermal stress, targeted plant nutrition applications, and the genotype × environment × management interaction. Several cardinal issues warranting further research were identified: the ripening-dependent accumulation and metabolism of carotenoids and the link between carotenoid profiles and volatile fractions, particularly the role of apocarotenoids as substrates in the synthesis of aroma volatile molecules; the coexistence of ethylene-dependent and ethylene-independent regulation of ripening processes in melons; physiological incompatibility in melon graft combinations and its implications for fruit quality; rootstock mediation of watermelon volatile fraction; the role of osmoregulatory molecules as l -citrulline in cell expansion and turgor affecting mesocarp firmness; stage-specific carbohydrate partitioning and metabolism in developing fruit and its potential manipulation through thermal treatments; robust model building on transplanting dates, resilient to genotype × environment interaction. Understanding the concerted effects of the genotypic, physiological and agro-environmental factors visited in the current review is instrumental in the efforts for improving quality and expanding market share for watermelon and melon fruit.

The viviparous urodeles Lyciasalamandra spp. are restricted to a narrow mountain range of ca. 30 km width along the southern Turkish Mediterranean coast and some adjacent Turkish and Greek islands. All species share a predominantly subterranean life-style in crevices of boulder fields, probably since their speciation about 10 million years ago. In this study we test the hypothesis that similar subterranean environmental conditions attenuates within- and among-species variation of demographic life-history features in four populations of Lyciasalamandra from three different taxa (L. atifi, L. billae, L. luschani) and from two altitudinal zones, the eumediterranean (0–400 m) and the supramediterranean (400–1100 m) belts or not. Skeletochronological age determination was successful in all 325 individuals sampled. Phalange bones showed a regular annual arrest of growth during winter. Local age at maturity varied between two and three years, maximum lifespan between nine and eleven years. Adult survivorship and subsequently estimated life expectancy of females exceeded slightly those of males, but sexual size dimorphism was absent in all taxa. L. atifi were significantly larger than the other species due large size at birth and subsequent fast subadult growth. L. billae shared the fast subadult growth, but small birth size and same age at maturity contributed to a smaller maximum adult size. L. luschani had a large birth size and slow subadult growth irrespective of the elevation of habitat resulting in the same maximum size of adults as present in L. billae. We concluded that a subterranean mode of living attenuated the thermal effects of altitude and that the minor, but detectable variation in life-history traits of the salamanders mainly resulted from the periods of surface activity.

Vegetable transplants grown in commercial high-density trays can quickly outgrow the optimal size for shipping and transplanting, limiting transplant performance, and marketing flexibility for commercial nurseries. Abscisic acid (ABA) and uniconazole can suppress shoot growth by inducing stress-adaptive responses and inhibiting gibberellin synthesis, respectively. We evaluated the effectiveness of the two growth regulators in prolonging marketability of ‘Florida 91’ and ‘Mariana’ tomato (Solanum lycopersicum L.) transplants at commercial nursery greenhouses in Texas and Florida. Spray treatments in the Texas experiment were 0 and 3.8 mm ABA at 7, 5, 3, or 1 days before maturity (DBM), and those in the Florida experiment were no spray control, 3.8 mm ABA at 7, 5, 3, or 1 DBM, and 34 μm uniconazole at 4 DBM. Both ABA and uniconazole showed minimal cultivar-specific effects. Different growth modifications were induced by ABA and uniconazole. First, suppression of stem elongation by ABA was reversible by 7 days after maturity (DAM), whereas that by uniconazole lasted for 20 days or until 16 DAM with up to 15% suppression in stem elongation. Second, only ABA inhibited leaf expansion and shoot dry matter accumulation. The primary growth-modulating effect of uniconazole was limited to height control, which is beneficial for producing compact transplants, rather than as a growth holding strategy. By contrast, the overall growth suppression by ABA is desirable for prolonging transplant marketability. Importantly, the magnitude of this growth suppression was moderate (up to 22% shoot biomass reduction at 8 DAM) and transient, followed by a rapid recovery. Furthermore, ABA caused relatively smaller inhibition in root growth, allowing sufficient root development and increasing the root-to-shoot ratio at 0 to 8 DAM. The growth suppression by ABA was maximal when it was applied at 7 to 5 DBM, indicating the age-dependent sensitivity of tomato seedlings to exogenous ABA. Although leaf chlorosis was induced by ABA in a similar age-dependent manner, it was transient and reversible by 7 DAM. These results suggest that ABA application 7 to 5 DBM is an effective growth holding strategy for tomato transplants.

Tillage practices are critical for sustaining soil quality necessary for successful crop growth and productivity. A three-year study (2012–2014) was carried out to evaluate the influence of strip and conventional tillage practices and three water status levels [T1 = 100% of evapotranspiration (ET) demands, T2 = 0.75T1and T3 = 0.5T1] on plant morphology, physiology, yield and quality of triploid (seedless) watermelon (Citrullus lanatus cv. Magestic). Soil chemical and biological properties were also assessed at the end of the experimental study. Tillage practices (strip or ST and conventional or CT) started in 2009 and are being carried out to the present date of 2016. Irrigation was established using a center pivot system. Photosynthesis rate (Pn), stomatal conductance (gs), and chlorophyll content index (SPAD) were measured at flowering, fruit development and harvest stage and vine length measured at the harvest stage. Total marketable yield and fruit quality (firmness and sugar content) were determined during the harvest period. Soil chemical and microbial analysis were conducted at the end of the experimental period (March 2015). No significant differences (P = 0.05) were found between water deficit treatments in vine length, SPAD, Pn, gs, fruit firmness, and sugar content during the three-year study, except for vine length in 2013. But, marketable yield from T1 treatment was significantly higher (P = 0.03) than T3 in 2013. Vine length and SPAD measured from the ST plots were higher than CT, especially in 2012. Interestingly, marketable yield from ST was 8.6, 9.7 and 14.9 t ha−1 higher than CT in 2012, 2013 and 2014, respectively. Additionally, fruit sugar content under ST was statistically higher (P = 0.05) than those from CT. After 6 years of tillage practices (2009–2015) in the same site, ST increased total bacteria by 49%, active bacteria by 27%, active and total fungi by 37%, nematodes by 275%, and electrical conductivity by 14% compared to CT. However, ST significantly increased root-feeding nematodes (harmful to plant roots) and reduced phosphorus and nitrate-N compared to CT. Although long-term studies aimed at assessing soil quality and cumulative yield are required to further validate our results, yield and fruit quality (sugar content) responses were consistent across three years and with promising abundance of soil microbial activities.

Effective nutrition and irrigation are important nursery strategies to produce high-quality seedlings able to withstand heat and drought stress in the field. The objectives of this study were 2-fold, first to identify the influence of two nitrogen (N) levels (75 and 150 mg·L−1) and two fertigation (FR) methods, overhead (OH) and flotation (FL) of artichoke (Cynara cardunculus cv. Green Globe Improved) transplants on root/shoot growth and leaf physiology during the nursery period. A repeated greenhouse experiment was conducted and morphophysiological measurements were determined at 4 and 7 weeks after seeding (WAS). The second objective was to determine the impact of the nursery treatments (FR method and N level) on the subsequent crop growth and yield under three field irrigation methods [surface drip, subsurface drip, and overhead-linear system (OH-L)]. Field measurements were conducted at 50 and 150 days after field transplanting (DAT) during Fall–Winter 2015. Transplants fertilized with 75 mg·L−1 N (low N) had improved root components as compared to those with 150 mg·L−1 N (high N), especially at 4 WAS. The low N transplants had higher root surface area, root length, root branching, thinner root diameter, and less shoot area than the high N transplants. Wilting for low N transplants was 13.5% less than that for high N at 5 DAT, with a total yield similar or slightly higher than those of high N. Although growth of OH and FL transplants was statistically similar at transplanting, those irrigated with OH (greenhouse) had a 10% higher yield than FL irrigated transplants, regardless of the field irrigation method evaluated. Overall, low N level (75 mg·L−1 N) applied with OH irrigation in the nursery positively improved the transplant root system and transplant quality of artichoke seedlings.

Vegetable growers require vigorous transplants in order to reduce the period of transplant shock during early stand establishment. Organic media containing solid humic substances (HS) are amendments that have not been comprehensively explored for applications in containerized vegetable transplant production systems. In this study, HS (1% v/v) were applied to a peat-based growth medium to evaluate pre- and post-transplant growth modulation of four economically important vegetable species. Those were: pepper, tomato, watermelon, and lettuce. Seeding for all species was performed in two periods in order to evaluate their post-transplant yield performance under drought (water deficit vs. well-watered) and heat (hot vs. cool season) stresses. Compared with control, HS-treated plants had: 1) increased leaf and root biomass after transplanting due to faster growth rates, 2) lower root/shoot ratio before transplanting, but higher after 10 days of field establishment, and 3) increased root length and surface area. The negative effects of heat and drought stresses on crop yield were more prominent in control plants, while HS-treated transplants were able to mitigate yield decreases. The results clearly demonstrated the benefits of using solid HS as a management input to improve transplant quality in these crop species.

Short-day onions (Allium cepa L.) grown in the southern regions of the United States are commonly undercut and then dried for a few days before the bulbs are clipped and harvested. We conducted a study to evaluate the effects of leaf cutting on bulb weight and pungency of short-day onions after plant lifting in ‘TG 1015Y’, ‘Legend’, and ‘Texas Early White’ cultivars. When about 50% of the leaf had collapsed, plants were lifted from the field and the leaf was either cut at the neck (cut) or left intact (uncut, control). The plants were laid out to dry for 0, 3, or 7 days in a greenhouse with natural ventilation and the pungency and weights of the bulbs and leaves (partially dried to approximate normal field curing or dry weight) were measured. In a bulb–leaf paired test, bulb pungency was retained at the initial level in the cut treatment, while it showed an increasing trend in the uncut treatment, resulting in a gain of ˜0.8 μmoles mL−1 after 7 days in ‘TG 1015Y’. However, leaf pungency in the uncut treatment had 2.5 and 4.8 μmoles mL−1 less than that of the cut treatment after 3 and 7 days, respectively. Among cultivars, bulb pungency generally showed that the cut treatment had lower pungency levels, with some variation in change patterns and magnitudes of difference by the cultivar. The mildest cultivar ‘Legend’ had no difference but the most pungent cultivar ‘TEW’ showed 1.0–1.3 μmoles mL−1 less pungency by the cut treatment. Bulb weight was not reduced by the cut treatment, while leaf dry weight was generally heavier in the three cultivars. We considered that the lower bulb pungency in onions from cut plants was attributed to the severance of translocation of flavor compounds from leaf to bulb. Therefore, leaf clipping at the time of lifting and subsequent field curing is beneficial for producing less pungent onions for some cultivars.

We implemented a wide field-of-view visible-light optical coherence microscope (OCM) for investigating ex-vivo brain tissue of patients diagnosed with Alzheimer’s disease (AD) and of a mouse model of AD. A submicrometer axial resolution in tissue was achieved using a broad visible light spectrum. The use of various objective lenses enabled reaching micrometer transversal resolution and the acquisition of images of microscopic brain features, such as cell structures, vessels, and white matter tracts. Amyloid-beta plaques in the range of 10 to [Formula: see text] were visualized. Large field-of-view images of young and old mouse brain sections were imaged using an automated [Formula: see text] stage. The plaque load was characterized, revealing an age-related increase. Human brain tissue affected by cerebral amyloid angiopathy was investigated and hyperscattering structures resembling amyloid beta accumulations in the vessel walls were identified. All results were in good agreement with histology. A comparison of plaque features in both human and mouse brain tissue was performed, revealing an increase in plaque load and a decrease in reflectivity for mouse as compared with human brain tissue. Based on the promising outcome of our experiments, visible light OCM might be a powerful tool for investigating microscopic features in ex-vivo brain tissue.

SUMMARY Inflammatory bowel diseases are a group of chronic inflammatory conditions that affect gastrointestinal tract due to inapt and continuous immune activation in response to a myriad of predisposing factors (most notably genetics, environmental impact and gut microbiota composition). It has been shown that vitamin D status can also play a role in the disease pathogenesis, as its deficiency is commonly observed in two major forms of inflammatory bowel diseases – Crohn’s disease and ulcerative colitis. Mounting evidence supports the concept of intricate relationship between gut dysbiosis and vitamin D metabolism, while suboptimal levels of this vitamin have been linked to increased clinical disease relapse rates, inadequate response to drugs, as well as decreased quality of life in patients with Crohn’s disease and ulcerative colitis. Consequently, the pertinent question is whether increased vitamin D supplementation and (on a population level) food fortification may bring significant benefit to the affected individuals. In this short review we discuss the synthesis, functions, status and food sources of vitamin D, appraise biotechnological facets of vitamin D status analysis and food fortification, and concentrate on novel developments in the field that describe its influence on intestinal microbiota and inflammatory bowel disease.

Vegetable transplants quickly outgrow the optimal size for shipping and transplanting, limiting sales, and marketing flexibility in commercial nurseries. Abscisic acid (ABA) and uniconazole can suppress shoot growth by inducing stress-adaptive responses and inhibiting gibberellin biosynthesis, respectively. We evaluated the effectiveness of the two growth regulators in prolonging marketability of ‘Excursion’ and ‘Revolution’ bell pepper (Capsicum annuum L.) transplants at commercial nursery greenhouses in Texas and Florida. Spray treatments in the Texas experiment were 0 and 3.8 mM ABA at 7, 5, 3, or 1 day before the anticipated maturity date (DBM), and those in the Florida experiment were no spray control, 3.8 mM ABA at 7, 5, 3, or 1 DBM, and 34 μM uniconazole at 4 DBM. Both experiments showed similar results with minimal cultivar-specific effects. Different growth modifications were induced by ABA and uniconazole. First, suppression of stem elongation by ABA was reversible by 7 days after the anticipated maturity date (DAM), whereas that by uniconazole lasted for 20 days or until 16 DAM with up to 15% reductions in stem length. Second, only ABA inhibited shoot and root dry matter accumulation. The growth modulating effect of uniconazole appears to be limited to height control, which is beneficial for producing compact transplants, rather than as a growth holding strategy. By contrast, the overall growth suppression by ABA is desirable for prolonging transplant marketability. Importantly, the magnitude of this growth suppression was moderate (9%–12% shoot biomass reductions at 7–8 DAM) and mostly reversible by 14–16 DAM. Furthermore, root growth inhibition by ABA occurred with a time lag of over a week, allowing sufficient root development and increasing root-to-shoot ratio at 0 DBM. Although these growth holding effects of ABA were generally maximized when it was applied at 7 or 5 DBM, leaf chlorosis and cotyledon abscission were also induced by ABA in a similar age-dependent manner. These results suggest that ABA application 3 DBM is an effective growth holding strategy with minimal negative-side effects for bell pepper transplants.

Seaweed extracts (SWE) are biodegradable and non-polluting to the environment, and have become popular as biostimulants. Their effects on spinach growth, physiology and nutrition value under drought stress were evaluated in a growth chamber study. Differential irrigations (100 and 50% evapotranspiration for full irrigation and drought stress, respectively) and Ascophyllum nodosum SWE application methods (water foliar, SWE foliar, SWE drench, SWE foliar and drench) were applied every 4 d. After 35 d, leaf growth, chlorophyll content and fluorescence, gas exchange, and nutrition value were analyzed. Under drought stress, leaf area, fresh and dry weight (FW and DW) were only 42, 42 and 60% of these under full irrigation, respectively. Drought stress also decreased leaf relative water content (RWC) and specific leaf area (SLA) from 89 to 76% and 179 to 139 cm2 mg−1, respectively. Gas exchange was reduced by drought stress although chlorophyll content and fluorescence were not altered. Drought stress had no direct effects on the leaf nutrition quality except for reduced ferrous ion chelating ability (FICA). Under full irrigation SWE had no effects on leaf growth, physiology and nutrition value but under drought stress SWE improved plant growth. Under drought stress A. nodosum SWE application increased leaf RWC from 76 to approximately 82% and leaf area by 16, 21 and 38% with SWE foliar spray, drench or both, respectively. Also, SWE increased leaf FW, DW and SLA by 20 to 32%, 11 to 22%, and 5 to 19%, respectively. The inhibition of gas exchange and increases of stomatal limitation induced by drought stress were reduced by SWE, irrespective of application methods. SWE application had no effects on phenolic, flavonoid, carotenoid, and antioxidant capacity, but reduced FICA. These results indicated that under mild drought stress A. nodosum SWE enhanced spinach growth by improving leaf water relations, maintaining cell turgor pressure and reducing stomatal limitation, which in turn led to large leaf area and high photosynthetic rate. A. nodosum SWE application negatively impacted nutritional quality by reduced FICA under drought stress.

The aim of this work was to determine how differences in lipids and starch content among diploid and triploid watermelon seeds affect respiration and the glyoxylate cycle during germination. In comparison to diploid watermelon seeds, the respiratory quotient (RQ) associated with CO2 release and O2 uptake in triploids was very high initially and declined through four days of germination. The high RQs may indicate unavailability of oxygen due to the thick seed coats of triploids while the lower RQs observed later are consistent with respiration of lipids. Isocitrate lyase (ICL) activity, a marker for the glyoxylate cycle, might be affected by the fatty acid levels, especially high linoleic acids (C18:2) in triploids with low germination. Lower ICL activity in triploid seeds could be physiologically relevant to higher levels of fatty acids, a response to lipid metabolism, and thus contribute to poor germination of triploids.

High seed germination and root vigour are important traits to improve post-transplant performance of artichoke (Cynara cardunculus var. scolymus) under heat stress conditions. The effects of exogenous applications of five ethylene regulators each at different concentrations were evaluated on germination and early root growth of artichoke at 23°C in two incubation assays. The ethylene precursors or promoters were DL-methionine (DL-MET), 1-aminocyclopropane-l-carboxylic acid (ACC) and 2-chloroethylphosphonic acid (ethephon, ETH); and ethylene inhibitors were aminoethoxyvinylglycine (AVG) and 1-methylcyclopropene (1-MCP). A subsequent study examined the effects of ETH concentrations on seeds exposed at 23 vs. 30°C (stress). Seed thermodormancy was significantly improved by the application of 30 μM L-1 ETH. At optimal temperature (23°C), early root growth was enhanced by ACC and ETH (range of 1-100 μM L-1) with increasing root hair density, root area and lateral roots (except with ETH at 30 μM L-1). Conversely, AVG induced primary root elongation but decreased root hair formation. At higher temperature (30°C), inhibition of early root growth was alleviated when seedlings were incubated at 30 μM L-1 ETH. Our results suggest that exogenous ethylene could be useful to alleviate heat stress on artichoke seeds and seedlings, which in turn may improve early growth during stand establishment. Fil: Shinohara, T.. Sanyu Consultants Inc.; Japón Fil: Martin, Eugenia Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; Argentina Fil: Leskovar, Daniel Ivan. Texas A&M University; Estados Unidos

Plants perceive environmental stress and use this information to modulate their regular pattern of development. Abscisic acid (ABA) mediates plant responses to many abiotic stresses. This study investigated the efficiency of short- versus long-term ABA exposure on critical morphological and physiological responses linked to functional changes in stomata, stomatal density, plant water status, photosynthetic activity and overall growth in bell pepper ( Capsicum annuum L.). ABA was applied to pepper seedlings as foliar at 0, 0.1 or 1.0 mM for 5, 10 or 15 consecutive days. A depressive effect of ABA on net photosynthetic rate (A CO2 ) and stomatal conductance (g s ) compared to control was found after 5-day ABA-exposure at 1.0 mM, and after 15-day ABA-exposure at 0.1 mM and 1.0 mM ABA. Plants quickly resumed the photosynthetic activity since no effect of ABA was found after a longer recovery. Temporary higher leaf water potential was observed in seedlings treated with ABA compared to control. At 17 days after the beginning of the experiment, the number of stomata at adaxial and abaxial side was reduced at 1.0 mM ABA-rate compared to 0.1 mM ABA for each ABA-day of exposure. ABA-rate at 1.0 mM decreased leaf weight, number and area with a more pronounced effect as ABA-days of exposure increased. Stem dry weight was almost unaffected by ABA-rate at 0.1 mM, but 1.0 mM decreased stem weight by 30% after 15-day ABA-exposure. The increased specific root length at 1.0 mM ABA-rate after 5- or 15-day ABA exposure suggested that ABA induced the growth of thinner roots. The delayed effect of ABA-rate and ABA-days of exposure was measured for plants allowed to recover for 23 days after the last application for the longest treatment. Growth parameters were generally affected by ABA after longer recovery. The effect of ABA on modulation of pepper seedlings growth and physiology was dependent on rate and length of exposure but recovery duration was important as well. These results provide new evidences that application of ABA at a specific rate and length of exposure could eliminate the risk of stressing young seedlings to the point of physiological injury as previously reported for some hardening techniques.

Xu C., Leskovar D.I., 2014. Growth, physiology and yield responses of cabbage to deficit irrigation . Hort. Sci. (Prague), 41: 138–146. Field experiments were conducted in two seasons to investigate growth, physiology and yield responses of cabbage ( Brassica oleracea L. cvs Pennant and Rio Grande) to deficit irrigation. In 2012 season, 50% of crop evapotranspiration (ETc) irrigation temporarily decreased plant size, reduced leaf area, fresh weight, relative water content, specific leaf area and gas exchange during late development, and decreased head fresh weight, size, marketable and total yield. Deficit irrigation at 75% ETc had little influence on plant growth and physiology, but it still reduced both marketable and total yield. In 2013 season, 75% ETc irrigation had little influence on plant growth, leaf characteristics, photosynthetic rate, head fresh weight and size, but it temporarily increased chlorophyll and carotenoid content, and decreased stomata conductance, transpiration, and marketable yield. Pennant, the green-head cultivar, had higher photosynthetic rate, head fresh weight, marketable and total yield than the red-head cultivar Rio Grande. In both seasons, deficit irrigations did not influence cabbage head dry weight, indicating that most yield reduction under deficit irrigations is related to water content.

Height control of vegetable transplants is important for improving their adaptability to shipping and transplanting operations. Abscisic acid (ABA) inhibits stem elongation but can also induce undesirable growth modification. To optimize its application timing for effective height control, we examined age-dependent sensitivity of various growth variables to ABA in two pepper cultivars ( Capsicum annuum L.). Bell pepper ‘Excursion II’ seedlings were sprayed once with 3.8 mM ABA at 25, 18, or 11 days before transplanting (DBT), or twice with 1.9 mM ABA at 25 and 18 DBT. Jalapeno ‘Colima’ seedlings were sprayed once with 3.8 mM ABA at 22, 15, or 8 DBT, or twice with 1.9 mM ABA at 22 and 15 DBT. For all treatments, the application rate was 0.71 mg ABA per plant with the spray volume of 0.61 L m −2 (0.71 ml/plant). Only ‘Excursion II’ maintained significantly shorter plant height in all ABA treatments until the transplanting stage, ranging from 80% to 88% of the control. By contrast, leaf chlorosis and overall growth delay were induced by ABA in ‘Colima’. Age-dependent sensitivity to ABA was evident in leaf area of both cultivars, and in stem diameter and shoot and root biomass of jalapeno ‘Colima’, all of which showed maximal reductions when 3.8 mM ABA was applied at the cotyledon stage (first application). These results suggest that ABA is effective in height control for bell pepper ‘Excursion II’, and that it should be applied at least one week after the emergence of first true leaf to minimize the negative side effects. Importantly, subsequent field evaluations demonstrated that the growth modulation by ABA was only transient with no negative impact on marketable yield.

In the carotenoid biosynthetic pathway, lycopene β-cyclase (LCYB) catalyzes the cyclization that converts lycopene into β-carotene. Only a single copy of LCYB was identified and was suggested to encode a chromoplast-specific LCYB (CYCB type) in watermelon [Citrullus lanatus (Thunb.), Matsum & Nakai]. Splicing variants in the 5′-untranslated region were identified, but alternative splicing did not provide an explanation of the regulation of carotenoid accumulation in watermelon flesh. A quantitative assay using real time-PCR showed that differential expression was not detected between red- and canary yellow-fleshed watermelon cultivars. LCYB promoter regions were isolated and characterized, and a sequence difference was identified in the promoter region between red and canary yellow LCYB alleles. This polymorphism did not change the expression of LCYB, but does provide a reliable marker for discriminating LCYB alleles for red and canary yellow flesh. To develop a PCR-based marker to distinguish between the two LCYB alleles, we designed primers flanking the polymorphic region. The newly developed marker, designated Clcyb.600, co-segregated perfectly with flesh color phenotypes and single nucleotide polymorphism (SNP) markers developed in our previous study. Moreover, the Clcyb.600 marker offers easier discrimination of LCYB alleles than SNP or cleaved amplified polymorphic sequence markers, as it does not require restriction enzyme digestion for genotyping. Genotyping of LCYB promoter alleles in various commercial cultivars and plant introductions indicated that watermelon cultivars can be classified into two groups, those carrying a red LCYB allele or a canary yellow LCYB allele.

Height control is important to produce compact vegetable transplants that are suitable for shipping and transplanting. Although abscisic acid (ABA) inhibits stem elongation, it can also induce other growth modifications. To optimize its application timing for effective height control, we examined age-dependent sensitivity of various growth variables to ABA in diploid ‘Summer Flavor 800’ and triploid ‘Summer Sweet 5244’ watermelon [Citrullus lanatus (Thunb.) Matsum & Nakai]. Seedlings were sprayed once with 1.9 mm ABA at 25, 18, or 11 days before transplanting (DBT) or twice with 0.95 mm ABA at 25 and 18 DBT. The application rate was 0.55 mg ABA per plant with a spray volume of 0.61 L·m−2 (1.1 mL/plant). Only the single-spray treatment at 25 DBT (cotyledon stage) suppressed plant height by inhibiting petiole elongation. This effect was similar in both cultivars with 13% to 14% reductions at the transplanting stage compared with the untreated control. Undesirable growth modifications were also induced by ABA. In both cultivars, all ABA treatments caused 16% to 23% shoot biomass reductions mainly by inhibiting leaf expansion. Additionally, ABA treatments reduced stem diameter and root biomass in ‘Summer Flavor 800’. The double-spray treatment had similar growth-modulating effects as the single-spray treatments, except that it induced cotyledon abscission in ‘Summer Flavor 800’. These results suggest that although ABA applied at the cotyledon stage can reduce watermelon transplant height, the benefit is limited because of overall growth reductions, which can occur regardless of application timing. On the other hand, in triploid ‘Summer Sweet 5244’, moderate shoot growth delay by ABA may be of value as a growth-holding strategy when transplanting is delayed because of inclement weather at the time of field establishment. Importantly, field evaluations demonstrated that the growth modulation by ABA is only transient with no negative impact on marketable yield and fruit quality.

Water scarcity associated with intense and frequent droughts has increased the need for the implementation of drought adaptation strategies that can save water and sustain crop productivity in water limited environments. A two season (2011 and 2012) study evaluated root growth, yield and fruit quality responses of cvs. Mission (muskmelon; reticulatus ), Da Vinci (tuscan; reticulatus ) and Super Nectar (honeydew; inodorus ) of melon ( Cucumis melo L.) to two irrigation rates (100% and 50% crop evapotranspiration (ETc)) on a silty clay soil under the semi-arid conditions of Texas. Deficit irrigation (50% ETc) increased root length density (RLD) in Mission, decreased in Da Vinci and did not affect in Super Nectar. Marketable fruit yield at 100% ETc irrigation was 77.1 t ha −1 in 2011 and 78.7 t ha −1 in 2012, but deficit irrigation caused a 30% decrease in marketable yield in both seasons, mainly due to a reduction in fruit size. Yield responses to deficit irrigation also varied with cultivar. A significant yield reduction of 43% in 2011 and 33% in 2012 was measured in Super Nectar, while for cvs. Mission and Da Vinci the reduction in yield was 24% and 30%, respectively in 2012. Deficit irrigation had no adverse impact on melon fruit quality; rather it increased total soluble solids content (23%) in Mission and β-carotene content (25%) in Da Vinci in 2011. At 50% ETc, agronomic water use efficiency (WUE; kg ha −1 mm −1 ) was improved in Mission (13%) in 2012 while it decreased in Super Nectar (21%) in 2011. These results showed that deficit irrigation can save 37–45% of irrigation water in Mission and Da Vinci cultivars ( reticulatus ) with a moderate reduction in economic yield. This practice may not be applicable for cv. Super Nectar ( inodorus ), as it reduced yield without improving water use efficiency.

Bioactive compounds in plant-derived foods provide essential human health benefits. However, the content and types of bioactive compounds may vary based on genetic and environmental factors. The present study examined the impacts of cultivar, fruit maturity stage (mature versus immature), and growing season (2008, 2009) on the concentration of bioactive compounds in diverse pungent and non-pungent peppers. Significant interactions were observed among cultivars, maturity stages, and growing seasons. Mature peppers generally had the highest content of ascorbic acid (782.0–2305.3 μg/g FW in 2008 and 693.5–2817.2 μg/g FW in 2009), and capsaicinoids (115.5–338.9 μg/g FW in 2008 and 93.8–326.3 μg/g FW in 2009) compared to immature peppers. Paprika-type peppers generally had the highest contents of ascorbic acid and flavonoids especially in mature fruits, while capsaicinoids were higher in all mature stage peppers. Flavonoid concentrations varied considerably depending on cultivar and maturity stage. Total phenolics were also significantly higher in mature fruits compared to immature peppers in both years. A positive correlation between total phenolics and DPPH radical scavenging activity was observed. This indicates that the health beneficial components in peppers could also vary as a function of cultivar, fruit developmental stage and production season. The genetic variability in bioactive compounds found in this study constitutes a useful genetic base for improving the nutrient quality of peppers.

In semiarid regions of the U.S., artichoke [Cynara cardunculus L. var. scolymus (L.) Fiori] seedlings planted in the field during late summer or early fall generally experience simultaneous high air temperatures and short drought episodes causing transplant shock and delay in root and shoot development. This experiment was conducted to determine the effects of heat (35/20 °C, day/night temperature regimes vs. 25/10 °C) and drought (30% water holding capacity vs. 60%) stresses on plant growth, physiology and water status of artichoke cv. ‘Green Globe Improved’ transplants during 14 days after transplanting (DAT). Heat stress significantly inhibited shoot but not root growth 14 DAT. In contrast, drought stress significantly inhibited root growth between 7 and 14 DAT. Transpiration (E), stomatal conductance (gs) and photosynthetic rate ( A CO 2 ) decreased by transplanting (within 24 h) regardless of treatments. Thereafter, E and A CO 2 significantly increased by heat compared to 25/10 °C temperature regime 3 DAT. However as heat stress progressed E, gs A CO 2 and leaf water potential were reduced. Drought stress sharply reduced E, gs and A CO 2 within 1 DAT and leaf water status as early as 3 DAT. The combination of heat and drought stress significantly reduced shoot and root growth 7 and 3 DAT, respectively. This suggests that to prevent transplant shock by heat and drought it is desirable to prevent leaf dehydration. Thus, consecutive greenhouse experiments were also conducted to evaluate the effects of three film-forming antitranspirants (Antistress, Transfilm and Vapor Gard) and abscisic acid (ABA: 0, 500, 1000, and 2000 mg L−1) foliar application on physiological responses and shoot water status of artichoke transplants exposed to drought stress (water withholding). ABA at 1000 mg L−1 enhanced drought tolerance of transplants, a response that was associated with the maintenance of shoot water status via stomatal closure. Film-forming antitranspirants were not effective to mitigate drought stress. These results suggest that exogenous ABA could be a useful plant growth regulator to condition artichoke transplants to withstand temporal drought stress conditions and reduce transplant shock.

Additional index words. Cynara cardunculus, earliness, 'Green Globe Improved', 'Imperial Star', photosynthesis Abstract. Globe artichoke is typically grown in Mediterranean and coastalareas. Because of the high profitability as a specialty crop, demand to develop production systems optimized for other semiarid and water-limited regions is rising. Field experiments were conducted over three seasons (2008-09, 2010-11, and 2011-12) in southwest Texas to investigate plant growth, physiology, and yield of artichoke grown as an annual system. Three strategies were evaluated: planting configuration (single and doublelines per bed), plasticulture (bare soil and black plastic mulch), and cultivars differing in maturity ('Imperial Star', early; 'Green Globe Improved', late). Each fall, transplants were established in the field at 2.03 m between rows and 0.90 m between plants (single line) or 4.06 m between rows and 0.90 m between plants (double line). In both cultivars, black plastic mulch enhanced plant growth (leaf number, plant height and width) and increased early yield; however, its effect on total yield and yield components was not consistent. Singlelineperbedsignificantlyincreasedheadnumberofjumboandlargesizeperplantas compared with double line in the 2009 season. Chlorophyll index was unaffected by either planting configuration or plastic mulch. Comparing cultivars, 'Green Globe Improved' had lower marketable yield but bigger head size than 'Imperial Star' in one and two seasons, respectively. Our results indicate that single line with black plastic mulch can be recommended to improve earliness and water savings as compared with the bare soil system for annual artichoke production. Commercial production of globe artichoke (Cynara cardunculus L. var. scolymus (L.) Fiori) in the United States is almost exclu- sively in California with major areas located along the central and south coast, the Coach- ella Valley in the southern inland desert, and the central valley. The total cultivated area has shown a decline in the last 2 years, from 3480 ha in 2009 to 2990 ha in 2011 (U.S. Department of Agriculture, 2012). How- ever, the average yield has increased to 14,570 kg·ha -1 with a total crop value of $48.5 million in 2011. A small number of hectares is also grown in the semiarid areas of the Wintergarden and Lower Rio Grande

This study evaluated growth, yield, quality and quercetin concentration in response to planting density and deficit irrigation of onion (Allium cepa L.) in southwest Texas over two years. Onion seeds (cv. TG 1015) were direct seeded in the field on November 11, 2007 and October 30, 2008 at two planting densities (PD), 397 (standard PD) and 494 (high PD) ×1000 seeds•ha-1. Three irrigation rates were imposed after plants were fully established, 100, 75, and 50% crop evapotranspiration rates (ETc). Overall, there were consistent trends for bulb size, yield and quality parameters in both seasons. The number of bulbs and total marketable yields significantly increased (7-14%) at high PD; however, high PD decreased bulb size as compared to standard PD. Deficit irrigation at 50% ETc decreased most growth components. Similarly 50% ETc rate decreased marketable yield by 27% and 19% in 2008 and 2009, respectively; while 75% ETc decreased only 8% in 2008 and 13% in 2009. Soluble solids content, pungency, and quercetin were not affected by irrigation or planting density in both seasons. These results suggest that growers in water-limited conditions could adjust planting densities and implement water conserving practices (e.g., 75% ETc rate) to target high-price bulb sizes without reducing flavor or nutritional components.