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1.
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2.
Samples of fruit from Valencia orange trees, grafted on either Volkameriana or sour orange rootstocks were examined after standard commercial shipment and handling. Tests demonstrated differences in physical properties and chemical composition due to the rootstocks, and in acceptability as judged by a large taste panel. Fruit from trees grafted on Volkameriana was inferior in a number of respects, notably ease of peeling and flavour; juiciness and ascorbic acid content were also lower.  相似文献   

3.
Summary

Data from experiments with carrots grown in phytotrons under different day and night temperatures at two locations in Norway and three harvesting dates were treated by means of Principal Component Analysis (PCA). No effect of the single temperature amplitudes were found, the significant main effects were due to the mean temperature levels of 12 and 188C, location and harvest date. The PCA visualized the effect of mean temperature level on sensory, chemical and physical variables. Differences between the two groups were mainly caused by variation in sensory variables, the first group being characterized by high score for whiteness, sweetness, acidic taste, crispness, juiciness, glucose, fructose and root length. The other group had a high score for colour, odour, overall taste and flavour parameters, firmness, dry matter, sucrose, a and b-carotene, root weight and root diameters.  相似文献   

4.
Summary

Shoot tips of two almond scion cultivars, ‘Ne Plus Ultra’ and ‘Nonpareil 15-1’, and one almond/peach hybrid rootstock were successfully cryopreserved using a one-step vitrification technique. Three week old in vitro cultures were cold-hardened at 4°C on the multiplication medium (Murashige and Skoog for ‘Ne Plus Ultra’ and the hybrid rootstock; Almehdi and Parfitt for ‘Nonpareil 15-1’) for three weeks. Shoot tips, 2–2.5 mm long, were excised and precultured for 1 d at 4°C on the same basal medium, without plant growth regulators, supplemented with 0.7 M sucrose. After the preculture, the shoot tips were incubated in vitrification solution at 25°C for 45 min for the almond scion cultivars and 60 min for the hybrid rootstock, and then stored under liquid nitrogen (LN) for at least 3 d. After rapid thawing at 30°C, the shoot tips were washed with the appropriate liquid basal medium containing 1.0 M sucrose and then cultured on the same basal medium, solidified with agar, but excluding NH4NO3 or (NH4)2SO4. Shoot regeneration was usually observed within 2–3 weeks. Survival after LN, recorded as the percentage of shoot tips that produced at least one new shoot four weeks after thawing, was 87.5, 60.0 and 72.5% for ‘Ne Plus Ultra’, ‘Nonpareil 15–1’ and the hybrid rootstock respectively. The one-step vitrification method is a promising simple technique for cryopreserving almond scion and rootstock shoot tips from in vitro cultures.  相似文献   

5.
SUMMARY

D-amygdalin is a toxic compound found in the kernels of some bitter almond cultivars.This compound is toxic because of its potential to release poisonous hydrogen cyanide. The D-amygdalin contents of the kernels of 18 commercial almond cultivars (Prunus dulcis Mill. = Amygdalus communis L.) and three wild genotypes (Amygdalus webbii Spach.) were determined by HPLC. In initial tests, two extraction procedures [100% (v/v) methanol or 4% (w/v) citric acid)], two different kernel cutting sizes (powdered or roughly-cut pieces), and two shaking techniques (mechanical shaking or sonication) were assessed. The results obtained showed that the method of extraction can have a strong effect on the extent of recovery of the potentially toxic compound, which varied by a factor of approx. 20-fold across the different extraction techniques.The greatest recovery of D-amygdalin from wild almond kernels was achieved with mechanical shaking of roughly-cut kernels in 100% (v/v) methanol, and this procedure was applied for all subsequent analyses of the D-amygdalin contents of all genotypes. The highest amounts of D-amygdalin were found in “bitter” cultivars and wild genotypes (716 – 23,025 mg kg–1), with lower values in “sweet” cultivars (0 – 158 mg kg–1). High levels of variability were observed both among the 18 almond cultivars and the A. webbii genotypes tested.  相似文献   

6.
苹果果实酚类物质含量与果实苦涩关系的研究   总被引：2，自引：0，他引：2  
乜兰春  孙建设 《园艺学报》2005,32(5):778-782
 以富士苹果为试材, 利用高效液相色谱(HPLC) 研究了果实酚类物质含量与果实苦涩的关系以及酚类物质在果实中的分布。结果表明, 苦涩的幼果中, 根皮素和儿茶素含量均高达成熟果实的30多倍; 表儿茶素、原花青素和绿原酸含量分别为成熟果实的10倍左右。在成熟果实中, 有涩味的果实其绿原酸、儿茶素、表儿茶素和原花青素含量显著高于风味正常的果实; 有苦味的果实其根皮素和原花青素含量显著高于风味正常的果实; 苦涩味均较强的果实其绿原酸、儿茶素、表儿茶素、根皮素和原花青素含量最高。苦痘病果病变组织中根皮素和原花青素含量分别是正常组织的15倍和3倍。绿原酸、儿茶素、表儿茶素和原花青素是引起苹果果实涩感的主要物质; 根皮素、儿茶素和原花青素是引起苦味的主要物质。成熟果实中绿原酸主要分布于种子、果心和果肉; 儿茶素、表儿茶素和槲皮素主要分布于果皮; 原花青素主要分布于果皮中, 果肉和果心中也有分布; 根皮素则主要分布于种子、果皮和果心中。  相似文献   

7.
Enhancing knowledge of urban foraging across different urban landscapes is an urgent matter given that about two-thirds of the world’s population is projected to live in urban areas by 2050, whilst 50 % of Africa’s population is expected to live in cities by 2030. This study was conducted in Lagos metropolis which is the economic hub of Africa’s most populous country. Data was collected using an in-person, semi-structured questionnaire from 347 persons who were 18 years or older to identify foragers and non-foragers, their sociodemographic profiles, and their foraging practices. Results revealed that about two out of three persons sampled forage to some degree. The collection happened more in domestic gardens (34 %) and streets (27 %) than in other foraging sites (such as unused lands, institutional grounds and lakes and riparian fringes). A total of 35 species were reportedly foraged within the metropolis, mostly for food (71 %) and medicine (26 %). Mango (Mangifera indica), pawpaw (Carica papaya), tropical almond (Terminalia catappa), fish (various species), bitter leaf (Vernonia amygdalina) and spinach (Spinacia oleracea) were the most gathered species. The distance travelled to foraging wild species ranged from 5 m to 25 km. The primary motivation for foraging was the acquisition of fresh and natural materials. However, some felt that foraging was a stressful activity. The unavailability of foraging sites and species was the major constraint to foraging in this megacity. Hence, efforts to increase the edible components of public green spaces and to provide free access could potentially allow more people to forage and make current foraging more secure. We suggest that making provisions for foraging in urban planning goals could contribute to the sustainable development of cities in Africa and elsewhere.  相似文献   

8.
Almond [Prunus amygdalus Batsch syn. Prunus dulcis (Mill.) D.A.Webb] trees are either self- or cross-incompatible, which results in lower fruit set and yields. Flower bagging, fluorescence microscopy, and polymerase chain reaction (PCR) were used to discriminate between self-compatible genotypes obtained from crosses of the self-incompatible female parents (‘121’ and ‘4’) with the self-compatible male parent (‘Tuono’). This study was performed on 80 almond genotypes. The results of this study showed that, in the first cross (‘121’ × ‘Tuono’), genotypes 5, 11, 13, 14, 17, 20, 27, 29, 31, 35, and 38 were identified as being self-compatible and, in the second cross (‘4’ × ‘Tuono’), genotypes 1, 2, 10, 11, 12, 15, 21, 23, 25, 32, 37, 38, and 40 were found to be self-compatible. There were some promising genotypes based on self-compatibility and nut and kernel characteristics; for example, genotype 40 had the highest mean fruit and kernel weights at 2.9 and 1.3 g, respectively. PCR can be used to identify self-compatible genotypes at the juvenile stage. Flower bagging under favourable climatic conditions not only discriminated between self-compatible almond genotypes, but can also be used to measure fruit set percentages. Flower bagging and fluorescence microscopy can be used to determine the level of self-incompatibility. Fluorescence microscopy identified self-incompatible genotypes, even under unfavourable conditions. In general, a combination of all three methods is recommended to increase the accuracy of detecting self-compatible genotypes of almond.  相似文献   

9.
Summary

‘Reinette du Canada’ apple (Malus domestica Borkh.), which has been declared a Protected Designation of Origin (PDO) product throughout the European Community, is severely affected by bitter pit during storage, but increasing demand for organic produce requires chemical post-harvest treatments to be replaced with organic practices. The objective of this work was to determine the optimum stage of fruit maturity to improve the storability of high quality ‘Reinette du Canada’ apple during storage without applying post-harvest treatments. Seasonal conditions influenced fruit quality and the occurrence of storage disorders in ‘Reinette du Canada’. Harvest maturity also influenced the quality of ‘Reinette du Canada’ apple during storage, with later harvests reducing the development of bitter pit and increasing the soluble solids content:titratable acidity (SSC:TA) ratio. This study suggests that the SSC:TA ratio was a useful parameter for determining the optimum harvest maturity for high acidity, ‘Reinette du Canada’ apple. High quality fruit were obtained after long-term storage when the SSC:TA ratio exceeded 11.0, and fruit firmness at harvest exceeded 90 N. If these thresholds were not achieved, the quality of harvested ‘Reinette du Canada’ apples may not be sufficient to market fruit with the PDO designation. The results of our study also suggested that skin hue angle (hº) measurements may provide a quick and useful index that could replace fruit firmness measurements in the future.  相似文献   

10.
Summary

Heirloom tomatoes (Solanum lycopersicum L.) such as ‘Cuore di Bue’ are highly appreciated by consumers for their outstanding quality and flavour. Nowadays, they are often grafted onto vigorous rootstocks in order to overcome several soil-borne diseases. The present study was conducted in 2007 and 2008 in Southern Italy. Plants of ‘Cuore di Bue’, an heirloom ‘oxheart’ tomato, were grown in a greenhouse either as non-grafted plants, or grafted onto two inter-specific (S. lycopersicum S. habrochaites) rootstocks (‘Beaufort F1’ and ‘Maxifort F1’) in order to evaluate their effects on vegetative growth, marketable yield, fruit quality, and the sensory properties of ‘Cuore di Bue’ tomato fruit. Growth analysis revealed that ‘Maxifort F1’ enhanced plant growth, particularly in terms of leaf area and leaf fresh weight. Grafted plants had higher leaf area ratios (by 13%) and higher leaf dry weight fractions (by 18%) compared to non-grafted ‘Cuore di Bue’ plants. Marketable yields increased by 20 – 25% in grafted plants in both years. However, total soluble solids (TSS) contents, titratable acidity (TA), and TSS/TA ratios were not significantly affected by grafting.Vitamin C contents decreased by 14 – 20% in both years in the fruit of plants grafted onto either rootstock. The sensory profiles of fruit were not modified by grafting, although taste panelists expressed a higher preference for purchasing fruit from plants grafted onto ‘Maxifort F1’. These results confirm that, when using the appropriate rootstock/scion combination, grafting can improve plant growth and the marketable yield of heirloom tomato fruit without reducing the sensory quality of the fruit or its biochemical parameters. However, grafting can reduce vitamin C contents and, thus, nutritional quality.  相似文献   

11.
Due to its abundance of taste and odour compounds the strawberry becomes more and more popular. But what makes the flavour of this fruit so extraordinary? Scientists from the Technische Universität München (TUM) provide an answer. They succeeded in the elucidation of the formation pathway of a key aroma chemical of strawberry fruit on the molecular level.  相似文献   

12.
 ‘恩七叶甜’绞股蓝新品种全草味清甜，有效成分种类与原推广品种（亲本）相同，但有效成分含量和产量显著提高，克服了亲本味极苦的缺点，有很大开发价值。  相似文献   

13.
Summary

An experiment was carried out over a six year period to relate the storage quality of ‘Cox’s Orange Pippin’ apples to the mineral composition of leaves, fruitlets and fruits and to the climatic conditions during development. The apples were sampled from 24 orchards over a wide geographic area. The extent to which physiological disorders, bitter pit and low temperature breakdown (LTB), and quality attributes, greenness and firmness, of stored fruit could be predicted either before or at harvest was determined. For each response variable, a short-list of up to 12 potential explanatory variables was selected from an initial set of up to 54 possible explanatory variables, using stepwise regression techniques. Predictive models were generated by selecting variables from the initial short-list using a cross validation technique. The average incidence of bitter pit in controlled atmosphere (CA) storage at 1.2% O2 (<1% CO2) was 4% compared with 12% for similar samples stored in air. Predictive models accounted for up to 67% of the variance in bitter pit in air-stored fruit but the percentage was lower (39%) for fruit stored in CA. The concentrations of calcium and potassium in fruit were particularly important for predicting bitter pit in air-stored fruit but less so for fruit stored in CA where more explanatory variables were required for prediction. Fifty one per cent of the variance of LTB in fruit stored in CA was accounted for by a nine-variable model incorporating three climatic variables. A simple three-variable model (leaf nitrogen concentration, harvest firmness and fruit dry weight) accounted for 67% of the variance in ex-store firmness and the addition of other nutritional and climatic variables increased the percentage variance accounted for to 76%. Seventy-one per cent of the variance in the greenness of fruit after CA storage was accounted for by a six-variable model. The possible physiological significance of the explanatory variables in each model is discussed.  相似文献   

14.
Summary

June-budded ‘Nonpareil’/‘Nemaguard’ almond (Prunus dulcis (Mill) D. A. Webb) trees were fertigated with one of five nitrogen (N) concentrations (0, 5, 10, 15, or 20 mM) from July to September. The trees were sprayed with either water or 3% urea in October, then harvested bareroot after natural leaf fall, and stored at 2°C. One set of trees was destructively sampled for total N content; the remaining trees were transplanted into N-free media in the spring after cold storage. After budbreak, these trees were supplied for 70.d with either N-free Hoagland’s solution or Hoagland’s solution containing 15N-NH4NO3. Nitrogen concentrations in both stem and root tissues were positively correlated with the N-fertigation concentration. Fall foliar urea applications increased levels of stem and root N regardless of the N-fertigation concentration. During the first 70 d of spring growth, the trees utilized nitrogen from both their reserves and spring fertilizer applications. The amount of N reserves used for growth of new shoots and leaves was proportional to the total amount of reserves. Trees with low N reserves relied primarily on the spring fertilizer as their source of nitrogen. We conclude, therefore, that both reserve N and spring-applied N fertilizers are important for enhancing the regrowth of bareroot almond nursery trees during establishment after transplanting. Nitrogen fertilization in the spring can especially improve the performance of trees with low N reserves.  相似文献   

15.
Summary

Twelve published simple sequence repeat (SSR; microsatellite) markers, belonging to the ssrOeUA-DCA, GAPU and UDO series, were tested in a panel of 46 accessions of olive germplasm belonging to 30 unique cultivars collected in seven Provinces of Sicily. Four well-known reference olive cultivars were also added. The analysis was carried out on an automatic capillary sequencer using fluorescent dyes, and fragment sizes were determined using internal standards. The results allowed us to rank the SSRs assayed according to their information content and reproducibility. Up to 115 alleles were identified (119, if those unique to sport mutations were included), the frequency of which allowed genetic relationships among accessions to be investigated. The probability that two unrelated genotypes displayed the same SSR pattern at all loci examined was calculated to be as low as 1.18 10–11. Sixteen accessions were identified as synonyms. Of these, eight matched perfectly with another accession at all SSR loci examined. The others showed one or two allelic differences from the reference accession. These were interpreted as mutations. Otherwise, all accessions were clearly separated from each other. Two likely parentages were also identified (‘Giarfara’ = ‘Nocellara del Belice’

‘Cacaridduni’; and ‘Pizzo di Corvo’ = ‘Nocellara Etnea’ ‘Tonda Iblea’). The genetic diversity of the pool represented by the unique accessions was very high, reflecting the richness of the olive germplasm accumulated in Sicily. A database of the accessions is available to the scientific community (http://www.unipa.it/germolive/ssr.html) to facilitate comparisons of data.  相似文献   

16.
In the present work the effects of the harvest time on variation of the quality parameters of several almond cultivars were evaluated. Studied cultivars came originally from three different countries: Italy (Supernova, Falsa Barese, Genco and Tuono); France (Ferragnes, Lauranne and Stelliette); Spain (Glorieta and Mas Bovera). The samples were collected in a field of the South of Italy during two harvest periods: at the beginning and at the end of August. Particularly, the highest free acidity content (increasing about the 24%) was observed during the ripening of Falsa Barese variety. Also the lipid content was increased and the Genco variety was that of the highest amount in both samplings. The fatty acids amount from the Mas Bovera cv almond kernels, particularly at the late harvest time, showed the best results (oleic/linoleic acids of 7.36 and high MUFAs/PUFAs value). The cluster analysis shows that this cultivar differs from the others in the oil composition. If on the first sampling some differences were observed, in the late harvest time all varieties combined in the same cluster with the exception of Mas Bovera and Ferragnes, provided of different acidic distributions. The analysis of minerals and trace element, K, Mg and Ca proved the major minerals present in all almond seeds.  相似文献   

17.
The effects of sulphate nutrition on watercress were investigated with respect to visual deficiency symptoms, growth response and flavour content as determined by sensory and gas-chromatographic methods. The plants were grown in a glasshouse, both in solution culture using plants propagated vegetatively and in sand culture using plants raised from seed, at six concentrations of sulphate in the nutrient medium. The two methods were complementary and led to substantially similar conclusions. There were steep increases in weight per plant, sulphur content and flavour strength with initial increases of sulphate concentration in the nutrient medium, followed by levelling off- at the highest sulphate concentrations. Sulphur requirements for maximum growth were satisfied at lower sulphate concentrations (0.20-0.25 meq/1) than those for maximum flavour development (0.75 meq/1).

There is evidence that watercress flavour consists of at least two types of components: (a) components which impart a bland, generalized vegetable taste and odour and (b) a specific component or components which are perceived as a burning sensation in the mouth accompanied by a characteristic odour. Production of the former is independent of sulphur nutrition. Enzymatic production of ß-phenylethyl isothiocyanate from the corresponding glucosinolate is believed to be responsible for the latter. There were highly significant correlation coefficients between the isothiocyanate content of fresh tissues and their total and organic sulphur contents.

The possibility of controlling watercress flavour in commercial production, with a view to meeting consumer preferences, is briefly discussed.  相似文献   

18.
Summary

The timing of fungicide and antibiotic applications in fruit crops often overlaps flowering and pollination. Numerous studies report detrimental effects of chemical applications on pollination, fruit set and yield. However, field results can be quite variable even when similar compounds are tested on the same crop. Problematic is that field variables unrelated to the effects of pesticides on reproductive activities can mask results. In the current study, we specifically investigated the effects of selected pesticide sprays applied to stigmas, on subsequent pollen germination and tube growth. Using two model systems, apple and almond, sprays were applied to detached emasculated flowers under constant laboratory conditions using an electronically controlled robotic apparatus which simulated a field sprayer. flowers were pollinated at specific times after spraying, and pollen tube numbers and growth assessed using fluorescence microscopy. The pesticides evaluated were for apple: captan, myclobutanil and streptomycin; and for almond: azoxystrobin, myclobutanil, iprodione and cyprodinil. In apple, captan significantly reduced pollen germination, by 20% compared with water controls when pollination was conducted 18 h after treatment. The number of tubes that reached the basal part of the style within 20 h was not affected. In contrast, myclobutanil and streptomycin had no significant effect on pollen tube growth. With almond, none of the sprays significantly affected pollen germination or tube growth.  相似文献   

19.
Summary

Chlorophyll fluorescence, skin coloration and surface contour were measured for apple (Malus domestica Borkh.) fruit with and without common storage and handling surface defects. Defects included C02 injury in ‘Empire’, bitter pit in ‘Jonagold’, superficial scald in ‘Cortland’, ‘Law Rome’, ‘Gala’ and ‘Red Delicious’ and bruising in ‘Cortland’. Measurements were made along a transect established on the fruit surface. The fluorescence parameters, minimal fluorescence (Fo), maximal fluorescence (Fm) and photochemical efficiency (Fv/Fm, where Fv = Fm - Fo) were relatively similar around the circumference of undamaged control fruit. Skin colour was not found to influence chlorophyll fluorescence. With the exception of bruises, there were marked changes in fluorescence in the areas where surface disorders or damage had developed. C02 injury and bitter pit reduced Fv/Fm, whereas superficial scald did not. However, scald symptoms were accompanied by a reduction in Fo and Fm. The reduction in Fo and Fm became more marked as scald symptoms intensified during post-storage holding at 22°C. Chlorophyll fluorescence may have some potential for sorting fruit having superficial defects.  相似文献   

20.
Sixteen nuclear and 10 chloroplast SSR markers were evaluated for 40 almond genotypes including cultivated almond, 18 related species and 5 interspecific-hybrid populations. Results establish the value of SSR (nuclear and chloroplast) markers for distinguishing different genetic lineages and characterize an extensive gene pool available to almond genetic improvement. Hierarchical analysis using integrated nuclear and chloroplast DNA markers support Prunus fenzliana, a species native to the northeast Iran, as a probable ancestor of the cultivated almond. Results also established the importance of interspecific hybridization and subsequent genetic introgression in the development of cultivated almond and demonstrate continuing value of an interspecific gene pool for modern cultivar improvement. Molecular results implicate a dissemination of the cultivated almond from Asia to the Eastern Mediterranean and subsequently the Western Mediterranean and the New World is supported by the molecular analysis of regional germplasm.  相似文献   

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