Phytochemical accumulation and antioxidant capacity at four maturity stages of cranberry fruit

Specific components of cranberry fruit are being associated with human health attributes, such as maintenance of urinary tract health and antioxidant status. Some of the chemical properties and antioxidant capacity of cranberry (Vaccinium macrocarpon Ait. cv. Pilgrim) fruits were investigated at light green, blush, light red and dark red maturation stages. Fruit total phenolics, total monomeric anthocyanins, soluble solids, titratable acidity and individual organic acids were examined. Antioxidant capacity of fruits were determined by both the ferric reducing antioxidant power (FRAP) and trolox equivalent antioxidant capacity (TEAC) assays. The fruit color was measured using a portable chromameter. A converse relationship was found between total phenolics and anthocyanin as fruits mature. Total phenolic concentration was declined from 7990 to 4745 mg GAE/kg fw, while total monomeric anthocyanin content was increased from 0.8 to 111.0 mg/kg fw from green to dark red stage. Brix was increased from 6 to 9.3% as well. The main organic acid was citric acid determined by the HPLC method. The antioxidant capacity of cranberries decreased to light red stage; when a fruit accumulates more anthocyanin the activity increased again in both FRAP and TEAC methods. Averaged antioxidant capacity measured was 12.61 and 17.48 mmol TE/kg fw by FRAP and TEAC methods.     

Effects of the commercial product based on Trichoderma harzianum on plant,bulb and yield characteristics of onion

Effects of the commercial product TrichoFlow WP™ (Agrimm Technologies Ltd., New Zealand), based on the fungus Trichoderma harzianum, on quality characteristics and yield of bulb onion was investigated. Bulb sets of the local cultivar Kantartopu was planted in soil with in and between row distances of 0.15 m and 0.40 m, respectively. The product, at considerably high dosages of 5 g m⁻², 10 g m⁻² and 15 g m⁻², was mixed with water and sprinkled once to the plots at planting. Analyses of data at harvest did not show statistical significance for Trichoderma effect on total bulb yield, bulb diameter, leaf length, number of shoot apex, %titratable acidity, number of internal (fleshy) leaves, number of external (papery) leaves, %soluble solids and %bulbs with diameters of 20–39 mm, 40–69 mm and ≥70 mm. The yields obtained from the plots treated with the dosages of 5 g m⁻², 10 g m⁻² and 15 g m⁻² and the control plots were 1063.7 kg da⁻¹, 1051.0 kg da⁻¹, 1066.5 kg da⁻¹ and 985.0 kg da⁻¹, respectively. Our results showed that high dosages of the Trichoderma product were not effective in enhancing onion bulb and yield characteristics under the given conditions.     

Phytochemical and antioxidant properties of anthocyanin-rich Morus nigra and Morus rubra fruits

In this study, phytochemical and antioxidant properties of anthocyanin-rich mulberry species of Morus nigra L. (black mulberry) and Morus rubra L. (red mulberry) fruits harvested from across Turkey were investigated. Fruit color, total phenolics (TP), total monomeric anthocyanin (TMA), titratable acidity (TA), and individual sugar and organic acid compositions were determined. Total antioxidant capacity (TAC) of fruits was assessed by both the trolox-equivalent antioxidant capacity (TEAC) and the ferric reducing antioxidant power (FRAP) assays. Black mulberry exhibited higher TP, TMA, TAC and TA when compared to red mulberry. The average TP contents of M. nigra and M. rubra were 2737 and 1603 μg gallic acid equivalent in g fresh weight basis (GAE/g fw), respectively. M. nigra had the richest amount of anthocyanin with an average of 571 μg cy-3-glu/g fw. Overall, TAC averaged 10.5 and 12.0 mmol TE/L by the TEAC and FRAP methods, respectively. We found that FRAP, TEAC, TP and TMA were significantly correlated (r = 0.64–0.99) with each other. Fructose (5.27 g/100 mL) and glucose (5.81 g/100 mL) were determined to be the major sugars in both mulberries. M. nigra displayed a higher TA (2.05 g/100 mL) than M. rubra (0.78 g/100 mL), with citric acid as the major acid.     

Application of extra sulfur to high-sulfur soils does not increase pungency and related compounds in shortday onions

Sulfur (S) nutrition has a strong influence on onion pungency, and the production of sweet onions in the high-sulfur soil of Texas is a challenge to growers. This study was performed to determine the effects of S applications to fields already having sufficient levels of soil S on pungency and related compounds in four shortday onion cultivars. The onion cultivars ‘Cougar’, ‘Legend’, ‘Texas Early White’, and ‘Texas Grano 1015Y’ were grown in three commercial fields at Edinburg, Mercedes, and Weslaco of the Rio Grande Valley of South Texas with applications of sulfur at 0, 13, and 26 kg S/ha. Pyruvic acid, bulb weight, extractable S in soil and total S in bulb, soluble solids content (SSC), flavor precursor compounds [also called S-alk(en)yl-l-cysteine-sulfoxides (ACSOs)], and total sugars were measured. The pyruvic acid level of onions was not increased by the S applications and showed no significant correlation with soil S levels in any of the cultivars at locations having 30 or 235 ppm S. The SSC, total S in bulbs, total sugars, and total ACSO content also showed no correlation with the S applications and soil S levels. Onion pungency and content of flavor precursor compounds were significantly influenced by cultivar and cultivar × location interaction. We conclude that onion pungency is not increased by application of extra S fertilizer to commercial fields already containing sufficient levels of soil sulfur.     

Accelerated storage losses in onion subjected to water deficit during bulb filling

Withholding irrigation during last stages of onion crops is a common practice to minimize losses in storage due to rots. However, it is unclear whether extended periods of water deprivation may affect bulb postharvest behaviour. In this study we analyze the effects of water deficit during the crop cycle on bulb weight loss and sprouting during storage. Two experiments were conducted: one in a glasshouse with two onion cultivars subjected to three treatments of water availability (100%, 80% and 60% of field capacity); the other in the field, with one of these cultivars, subjected to two water availability treatments (dryland and irrigated twice during bulb filling). In both experiments five destructive samplings were done along crop development to assess plant height, number of green leaves, bulb and neck diameter, and whole-plant dry weight. Bulbs were harvested when 50% or more of the tops fell over. Harvested bulbs were classified by weight and then kept in a ventilated chamber at a mean temperature of 15 °C and weighted every two weeks, up to six months. Water deficit led to a significant reduction of bulb size, an acceleration of sprouting and an increased rate of weight loss during storage in both cultivars and under both experimental conditions. Hence, restricted irrigation during extended periods may have negative effects on the conservation of stored onion bulbs which suggests the need to finely adjust water management in this crop.     

Effect of smoke-water and a smoke-isolated butenolide on the growth and genotoxicity of commercial onion

Smoke-water and a biologically active butenolide compound (3-methyl-2H-furo[2,3-c]pyran-2-one) derived from burning plant material, show stimulating effects on a number of agricultural and horticultural crops. In these trials, onion (Allium cepa L.) plants were treated (drenched) with either a 1:500 (v/v) smoke-water solution or a butenolide solution of 10⁻¹⁰ M under greenhouse conditions. Onion plants supplied with smoke-water and butenolide solution exhibited a significantly greater number of leaves, increased leaf length, and a higher fresh and dry leaf weight than untreated plants at 175 days after seed sowing (DASS) (third harvest). In addition, smoke-water and butenolide-treated onion plants exhibited a significantly higher bulb diameter and bulb weight than untreated plants, when these plants were harvested at 175 DASS. Overall, smoke-water was more effective than butenolide and achieved the highest harvest index. Genotoxicity was not detected in the bulbs of onion when they were treated with either smoke-water or butenolide.     

Variation in total phenolics and antioxidant capacity among European plum genotypes

Our objective was to determine the amount of variation in total phenolics and antioxidants present in European plum fruits, so that it can be utilized in breeding programs to enhance the health benefits. Total antioxidant capacity and total phenolic content of the fruit, and the fruit skin color were determined in 20 genotypes, comprising of released varieties and advanced selections of European plums. Among the 20 genotypes, the total antioxidant capacity ranged from 105 to 424 mg ascorbic acid equivalents (AAE)/100 g fresh weight (FW) while the total phenolic content was 86–413 mg gallic acid equivalents (GAE)/100 g FW. The two parameters had a strong correlation of r² = 0.96. A direct correlation between skin color intensity and total phenolic content could also be observed. This study demonstrates that there is adequate variation in total phenolic compounds and antioxidants within European plums and hence there is potential for improvement towards enhancing these health-promoting phytochemicals in this fruit.     

Effect of application methods of organic fertilizer on growth,soil chemical properties and microbial densities in organic bulb onion production

This study was carried out to maximize the fertilization efficiency of mixed organic fertilizer (OF) for organically managed onion (Allium cepa L.) production during the one growing season of 2005–2006. The organic fertilizer was made of organic materials like sesame oil cake, rice bran and molasses and minerals like illite and mountainous soil. Four organic topdressing treatments, which all followed the same basal fertilization with solid OF, consisted of solid OF without mulch (OF/OFnM), liquid organic fertilizer without mulch (OF/LOFnM), liquid organic fertilizer under mulch (OF/LOFuM) and liquid organic fertilizer over mulch (OF/LOFoM). Chemical fertilizer (CF) and no fertilizer (NF) were treated as controls. The solid organic fertilization base was 2.0 ton ha⁻¹, and 4.57 ton ha⁻¹ and was used for topdressing. The total amount of liquid organic fertilization was 133.2 ton ha⁻¹, which was divided into 6 applications from February through March. The OF/LOFuM and OF/LOFoM topdressings did not reduce onion height, leaf number or bulb diameter as compared to chemical fertilizer, whereas no mulch treatments made onion growth significantly poorer. Onion top weight in CF was significantly higher than that in OF groups at the peak growth stage, while there was not much difference in bulb weight between the CF and OF/LOFoM treatment. Finally, the onion marketable yield was 45.9 ton ha⁻¹ in the OF/LOFoM treatment, which exceeded that in the CF treatment by up to 1.9 ton. Furthermore, OF/LOFoM was the most effective among all the treatments in transferring the nutrients from sink to source. CF made the soil pH more acidic than OF did, and the electrical conductivity (EC) remained higher with CF than OF as well. While organic fertilizer helped to keep the NO₃-N content stable throughout the growing season, the concentration rapidly oscillated up and down according to CF fertilization. Organic fertilizer increased population number of soil microorganisms like aerobes, actinomycetes in the field.     

Antioxidant capacity,antioxidant compounds and antioxidant enzyme activities in five date cultivars during development and ripening

Antioxidant capacity, antioxidant compounds and antioxidant enzyme activities in dates of five cultivars during development and ripening were studied in the 2009 and 2010 seasons. Fruit growth followed a smooth sigmoid curve with maximum weight at the bisir stage. Both the antioxidant capacity measured by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method and the antioxidant compound (phenols, tannins and vitamin C) concentrations decreased from young stages through to the maturation and the ripening stages. The antioxidant capacity was highly positively correlated with the concentration of antioxidant compounds in most cultivars. The activities of the antioxidant enzymes, peroxidase, catalase and polyphenoloxidase (PPO) increased from the hababouk through to the kimri and/or the bisir stage, upon cultivar, and thereafter, declined at the ripening stages. The possible relation of these biochemical changes with fruit maturation and ripening was discussed.     

The impact of sodium chloride on root growth,cell division,and interphase silver-stained nucleolar organizer regions (AgNORs) in root tip cells of Allium cepa L.

To evaluate genetic damage, parameters including root growth, chromosomal aberrations, and interphase silver-stained nucleolar organizer regions (AgNORs) in root tip cells of Allium cepa L. were investigated after treatment with NaCl (40–160 mM). The results showed that NaCl caused a decrease in root growth. All concentrations of NaCl showed an inhibitory effect on dividing cells in root tips of A. cepa L. and caused a reduction in mitotic index values. Upon exposure to NaCl, roots exhibited various mitotic abnormalities, including c-mitosis, anaphase bridge, and chromosome stickiness. In addition, interphase cells with micronuclei, budding nuclei, and unequal-sized nuclei were observed. Moreover, total cell aberration increased with increasing NaCl concentration. For AgNOR parameters, the average number of AgNORs per nucleus decreased in roots treated at all NaCl concentrations. The singular AgNOR area and whole AgNOR area in the nucleus containing 1–3 AgNORs were inversely proportional to NaCl concentrations.     

Exogenous putrescine reduces flooding-induced oxidative damage by increasing the antioxidant properties of Welsh onion

Soil flooding is an environmental factor of seasonal occurrence that negatively affects plant performance. Polyamines play an important role in the plant response to adverse environmental conditions including flooding stress. The objective of the present study was to assess the comparative oxidative damage to Welsh onion plants caused by flooding stress and to examine the role of putrescine (Put) in this response. Welsh onion plants were treated with Put prior to 10 d flooding. A positive effect was observed when treating with 2 mM Put. Exogenous application of Put resulted in alleviation of flooding-induced reduced relative water content, plant growth and chlorophyll fluorescence. Superoxide radical (O₂⁻) and hydrogen peroxide (H₂O₂) contents were also reduced in stressed plants after Put pre-treatment and thereby the oxidative stress in plant cells was lowered. The antioxidant system, as an important component of the waterlogging-stress-protective mechanism including α,α-diphenyl-β-picrylhydrazyl (DPPH)-radical scavenging activity, superoxide anion radical scavenging, metal chelating activities and reducing power, can be upgraded by Put, which is therefore able to moderate the radical scavenging system and to lessen oxidative stress. Under non-flooding conditions, the anti-oxidative activity of Welsh onion was regulated and elevated by Put pre-treatment. These results suggest that Put confers flooding tolerance to Welsh onion, probably through inducing the activities of various anti-oxidative systems. Thus, exogenous 2 mM per plant of Put 24 h prior to flooding could alleviate flooding stress.     

Early detection of graft incompatibility in apricot (Prunus armeniaca L.) using phenol analyses

The study investigated the role of phenols in apricot graft incompatibility. Assays of phloem with cambium from 1-year-old apricot trees of cultivars Marlen, Leskora and Betinka which were grafted on the rootstocks of different genetic origin: M-LE-1, Lesiberian, MY-KL-A, Tetra, Penta, Green Gage, Julior, MRS 2/5 and Isthara were analysed with HPLC (together 23 scion/stock combinations). The phloroglucinol, catechin, p-coumaric acid and further non-identified phenols with the retention time 23–25 and 30 min were determined. The content of individual phenol compounds was related to specific cultivar/rootstock combination. The minimum number of statistical significant differences in the phenol content between tissues above and below graft union was established in homospecific combinations (P. armeniaca/P. armeniaca). Cultivars Marlen, Leskora and Betinka differ in the degree of compatibility or incompatibility with rootstocks. The pattern of non-identified phenol 23 in different graft combinations is similar to catechin and p-coumaric acid.     

Effect of three Greek arbuscular mycorrhizal fungi in improving the growth,nutrient concentration,and production of essential oils of oregano and mint plants

Arbuscular mycorrhizal fungi have been widely used in agriculture to improve the cultivation of many crops. One of the aims of this study was the isolation and molecular identification of arbuscular mycorrhizal fungi isolated from mountain areas of Northern Greece (Ritini Pieria, Elatochori Pieria, Ambelakia Ossa). Only three isolates were obtained; two of Glomus etunicatum and one of G. lamellosum. The second objective of this study was to investigate the effect of these arbuscular mycorrhizal fungi on the concentration of macro- and micronutrients in tissues, the quantity and quality of essential oils and the growth of oregano and mint plants (two widely used aromatic plants in Greece). It was found that mycorrhizal oregano and mint plants had a higher content of essential oils and nutrient elements, and grew better than non-mycorrhizal plants. In addition, the composition of the essential oil in mycorrhizal plants differed from the oil of non-mycorrhizal plants. These results suggest that the use of mycorrhizal fungi may allow plant growth in low fertility soils, reduce fertilizer inputs and increase aromatic plant production of essential oils, They also indicate that it may be possible to use mycorrhizae to affect the quality of the essential oil produced.     

Conversion of chromosome-specific RAPDs into SCAR-based anchor markers for onion linkage maps and its application to genetic analyses in other Allium species

Integration of previously developed Allium cepa linkage maps requires the availability of anchor markers for each of the eight chromosomes of shallot (A. cepa L. common group Aggregatum). To this end, eight RAPD markers originating from our previous research were converted into SCAR markers via cloning and sequencing of RAPD amplicons and designing of 24-mer oligonucleotide primers. Of the eight pairs of SCAR primers, seven resulted in the amplification of single bands of the original RAPDs, and the remaining primer set amplified an additional band. The results of Southern hybridization using RAPD amplicons from genomic DNA of Japanese bunching onion (Allium fistulosum L.)—shallot monosomic addition lines indicated that five SCAR markers were single shallot chromosome-specific markers and were not detected in genomic DNA of A. fistulosum. The eight SCAR primer pairs were applied to other Allium species and exhibited three types of amplification profiles, namely RAPD amplicons observed only in shallot, in shallot and Allium vavilovii, and in several Allium species. A mapping study using 65 F₂ plants generated by the selfing of one interspecific cross A. cepa × Allium roylei individual integrated the SCAR marker SAOE17₅₀₀ into chromosome 5 as expected. The results of the present study show that the eight SCAR primer sets specific to shallot can facilitate the mapping in A. cepa and can also serve as anchor points between maps of different Allium species.     

Phytochemical and antioxidant properties of selected fig (Ficus carica L.) accessions from the eastern Mediterranean region of Turkey

Fig has been a typical fruit component of the health-promoting Mediterranean diet for a very long time. Phytochemical characters and antioxidant capacity of green-, yellow-, brown-, purple-, and black-fruited fig (Ficus carica L.) accessions were investigated. In this study, total phenolics (TP), total anthocyanins (TA), fructose (FRUC), glucose (GLUC), sucrose (SUC), and variables (such as L*, a*, C*, and hue°) describing fruit skin colors were examined. Also, the antioxidant capacity (TAC) of fig fruits was determined by the ferric reducing antioxidant power (FRAP) assay. Antioxidant capacity was significantly correlated with the polyphenol and anthocyanin (r = 0.74 and 0.63, respectively) contents of fruits. Black fig accessions had the highest TAC (range of 7.9–16.1, mean 12.4 Fe²⁺ mmol/kg FW), TA (range of 32.3–356.0, mean 128.4 μg cy-3-rutinoside/g FW), and TP content (range of 69.1–220.0, mean 118.9 mg GAE/100 g FW). These black-fruited accessions had 2-fold greater TAC, 15-fold greater TA, and 2.5-fold greater TP than green and yellow fig accessions. However, the FRUC, GLUC, and SUC content of brown and purple fig accessions were higher than those of other color groups. The predominant sugars present were fructose (∼56%) and glucose (∼43%), as determined by HPLC.     

分蘖洋葱与大蒜间作对大蒜开花的化感作用

以大蒜(Allium sativum)‘伊宁红皮’和抽薹型分蘖洋葱(Allium cepa var. aggregatum)‘M-4’为试验材料,通过间作,分析分蘖洋葱对大蒜开花的影响。结果表明,分蘖洋葱与大蒜间作,可以显著提高大蒜植株生长势,平均株高和假茎粗分别为96.3 cm和10.6 mm,比对照分别增高6.1 cm,增粗2.4 mm。间作的分蘖洋葱可促进大蒜的生殖发育,抽薹期比对照提前4 d,功能性大蒜小花数增多,减少气生鳞茎的数和大小,而且上调花分生组织属性基因gaLFY和AsFUL的转录水平。抽薹型分蘖洋葱与大蒜间作具有促进大蒜功能花发育的化感效应,有利于实现大蒜育性恢复。     

Effect of co-cultivation and crop rotation on corm rot disease of Gladiolus

Field and pot experiments were conducted to evaluate the effect of co-cultivation and crop rotation on the growth and corm rot disease of gladiolus (Gladiolus grandiflorus sect. Blandus) cv. Aarti caused by Fusarium oxysporum f.sp. gladioli (Massey) Snyd. and Hans. In the field experiment, gladiolus was co-cultivated with 10 agricultural/horticultural crops viz. Allium cepa L., Brassica campestris L., Capsicum annuum L., Eruca sativa Mill., Helianthus annuus L., Tagetes erectus L., Zea mays L., Vinca rosea L. and Rosa indica L., in a soil infested with F. oxysporum. All the crops except V. rosea and R. indica reduced disease incidence. The effect of H. annuus and T. erectus was significant and more pronounced than other co-cultivated crops. In general, root and shoot dry biomass, corm fresh weight, number of cormlets and number of flowers per spike decreased as compared to the un-inoculated monoculture gladiolus treatment (negative control) but these parameters enhanced as compared to the F. oxysporum inoculated monoculture gladiolus treatment (positive control). In a pot experiment, all the crops of the field experiment except V. rosea and R. indica were sown in rotation with gladiolus. Pot grown plants of different species were harvested at maturity and the soil was inoculated with F. oxysporum. Gladiolus was cultivated 1 week after inoculation. Disease incidence was significantly suppressed in all the treatments ranging from 29% to 53%. The highest suppression of disease incidence was recorded in T. erectus (53%) followed by B. campestris (49%). The effect of preceding crops on various vegetative parameters was similar in the pot experiment to that of the field experiment. The present study suggests that corm rot disease of gladiolus can be managed by mixed cropping of H. annuus and T. erectus or cultivation of T. erectus and B. campestris in rotation.     

The genotypic effects on the chemical composition and antioxidant activity of sea buckthorn (Hippophae rhamnoides L.) berries grown in Turkey

In this study, chemical composition of berries of 10 sea buckthorn (Hippophae rhamnoides L.) genotypes in Turkey was investigated. The total phenolic content of the berries ranged from 21.31 mg gallic acid equivalents (GAE) per g dry weight basis to 55.38 mg GAE per g. The highest antioxidant activity was 93.54% (similar to the standard BHT at 200 mg/L) and the lowest was 80.38%. There was no correlation (R = 0.688) between the total phenolic content and the antioxidant activity. The major fatty acids in berries were palmitoleic acid (35.48%), followed by palmitic acid (28.13%), oleic acid (22.89%) and linoleic acid (3.96%). Total soluble solid content of sea buckthorn genotypes varied from 10.15 to 14.80%, titratable acidity varied from 2.64 to 4.54%, the pH varied from 2.63 to 2.98 and Vitamin C varied from 19 to 121 mg/100 mL. The average content of minerals in the sea buckthorn berries of different genotypes was 20,800 ppm N, 7100 ppm P, 7260 ppm K, 1960 ppm Ca, 1465 ppm Mg, 32 ppm Zn, 24 ppm Cu, 22 ppm Mn and 7 ppm Fe.     

Genetic characterization of Allium tuncelianum: An endemic edible Allium species with garlic odor

Allium tuncelianum (Kollman) Özhatay, Matthew & ?iraneci is a native species to the Eastern Anatolia. Its plant architecture resembles garlic (Allium sativum L.) and it has mild garlic odor and flavor. Because of these similarities between two species, A. tuncelianum has been locally called “garlic”. In addition, both A. tuncelianum and garlic has 16 chromosomes in their diploid genomes. Recently, A. tuncelianum has been suggested as the wild progenitor species of garlic. In this study, amplified fragment length polymorphisms (AFLP) markers and nucleotide sequence analysis of the internal transcribed spacer region (ITS) were used to assess genetic and phylogenetic relationships among A. tuncelianum, garlic and some other Allium species. AFLP analysis demonstrated that A. tuncelianum and garlic are genetically distinct and they are likely different species. Phylogenetic analyses based on the nucleotide sequence of ITS suggested that A. tuncelianum and garlic are distinct species and placed A. tuncelianum, garlic, Allium ampeloprasum and Allium scorodoprasum into the same clade in the neighbor joining dendrogram and in the consensus tree of parsimony analysis. However, A. tuncelianum was phylogenetically less related to garlic than either A. ampeloprasum or A. scorodoprasum, suggesting that A. tuncelianum may not be the immediate wild ancestor species of garlic. Further studies to generate hybrid progeny between A. tuncelianum and garlic (if possible) could provide more information on the homology between the chromosomes of A. tuncelianum and garlic and genetic relationships between these two species.