Evaluating the effectiveness of different strategies for calcium application on the accumulation of calcium in apple (Malus × domestica Borkh. ‘Braeburn’) fruit

Summary

Orchards displaying calcium (Ca) deficiency are a common phenomenon worldwide, despite the presence of sufficient Ca in the soil and the plant. A 3-year trial was conducted between the 2007 – 2008 and 2009 – 2010 growing seasons to evaluate the contributions of soil and foliar Ca applications to Ca concentrations in ‘Braeburn’ apple (Malus × domestica Borkh.) fruit. Ca(NO₃)₂ (Calflo; Yara Africa, Fourways North, South Africa) was applied as six separate foliar sprays until run-off. Applications were made at 1-week intervals between approx. 21 – 70 d after full bloom (DAFB) at 6.75 ml l^–1. Soil applications of Ca (Tropicote^TM; International ASA, Oslo, Norway) at 300 kg ha^–1 were applied at fruit set, or after harvest, according to standard practice. Mineral analysis was conducted to assess the soluble Ca concentrations of whole fruit (without pips and stalks), to quantify the contribution of foliar sprays or soil-applied Ca. Fruit Ca concentrations were maintained at satisfactory levels (4.5 mg Ca 100 g^–1 FW) at harvest by applying a series of six foliar sprays early in the season (for all seasons) during the trial period. Fruit Ca concentrations at 80 DAFB were highest in the treatments with foliar applications of Ca. In 2009 – 2010, Ca concentrations in apple fruit were lowest (8.38 mg 100 g^–1 FW) for soil application of Ca at fruit set. Ca applications to soil after harvest in the previous season, and soil applications shortly after fruit set in the current season, did not significantly increase Ca concentrations in current-season fruit, providing soil Ca levels were above the minimum requirement for apple trees. A possible explanation is that apple trees regulate their uptake of Ca through the roots when soil Ca is available in sufficient quantities. This confirms the importance of active root growth for efficient Ca uptake by apple trees when applying Ca to the soil.     

Varietal differences in the chlorogenic acid,anthocyanin, soluble sugar,organic acid,and amino acid concentrations of eggplant fruit

Summary

Eggplant (Solanum melongena L.) is an important crop in Japan, with a long history of cultivation. Although many eggplant cultivars and lines have been developed, their nutrient concentrations, including phenolic compounds, have not been investigated in detail. In the present study, we investigated varietal differences in the concentrations of taste (e.g., soluble sugars, organic acids, and amino acids) and functional (e.g., chlorogenic acid, anthocyanins, and amino acids) compounds in eggplant fruit using 34 cultivars and lines with diverse growth habits, fruit shapes, sizes, and colours. The concentrations of taste and functional compounds differed among cultivars and lines. Variations in chlorogenic acid [0.1 – 2.5 mg g^–1 fresh weight (FW)] and anthocyanin (0.0 – 0.4 A₅₃₂ units g^–1 FW) concentrations were greater than those of soluble sugars (e.g., sucrose, 0.5 – 1.7 mg g^–1 FW; glucose, 7.6 – 13.7 mg g^–1 FW; fructose, 6.2 – 15.0 mg g^–1 FW) and organic acids (e.g., citric acid, 0.07 – 0.21 mg g^–1 FW; malic acid, 0.9 – 1.9 mg g^–1 FW). We also found that the coefficient of variation in amino acid concentrations varied with amino acid. Glutamine (27.4 – 135.8 mg 100 g^–1 FW) and arginine (4.5 – 23.1 mg 100 g^–1 FW) had the largest variation between varieties. These results indicate the importance of cultivar selection to optimise the concentrations of ingredients and will contribute to improvements in the functionality of eggplant through breeding.     

A Note on the Graft Compatibility of Native Wild Species. I. With Apple and Pear

Summary

Mango (Mangifera indica L.) is one of the most important tropical fruits in the World. Mango leaves, bark, and fruit (pulp, peel, and stone) are rich sources of bio-active compounds (BaCs) such as proteins [0.36 – 0.40 g 100 g^–1 fresh weight (FW) of pulp; 1.76 – 2.05% (w/w) of peel; 66.1 g kg^–1 of kernel flour; and 3.0% (w/w) of leaves], vitamin A [0.135 – 1.872 mg 100 g^–1 FW pulp; 15.27 International Units (IU) in kernels; 1,490 IU in leaves], vitamin C [7.8 – 172.0 mg 100 g^–1 FW of pulp; 188 – 349 µg g^–1 FW of peel; 0.17 g kg^–1 DW of kernel flour; 53 mg 100 g^–1 dry matter (DM) in leaves], carotenoids (0.78 – 29.34 µg g^–1 FW of pulp; 493 – 3,945 µg g^–1 FW of peel), mangiferin (1,690.4 mg kg^–1 DM in peel; 4.2 mg kg^–1 DW of kernel extract), phenolic compounds, dietary fibre (DF), carbohydrates, minerals, and other anti-oxidants known to have medicinal, nutritional, and industrial benefits. Bio-active compounds exist in functional foods and can protect us against diseases via several mechanisms. The anti-oxidant properties of several BaCs are important to protect against diseases related to oxidative stress. Fruit intake provides us with anti-oxidants that may act in a synergistic way to offer protection. In mango fruit, only the pulp is used, while all other parts are discarded and cause environmental pollution. The importance of all the different parts of mango fruit and trees should not be disregarded. With a global increase in health issues there is an increasing demand for natural foods. Hence, there is need to study all the bio-active constituents in mango to provide greater insights into their medical, nutritional, and industrial applications, as well as their role(s) in defending of the plant. This review aims to assist in the proper utilisation of mangoes to improve nutrition and health, as well as to improve our understanding of the defence mechanisms in plants that depend on these compounds.     

Response of kiwifruit (Actinidia deliciosa cv. Allison) to post-harvest treatment with 1-methylcyclopropene

Summary

Experiments were conducted to observe the effect of different concentrations of 1-methylcyclopropene (1-MCP) on the post-harvest life and quality of ‘Allison’ kiwifruit (Actinidia deliciosa). Fruit were treated with 1-MCP at 0.5 µl l^–1, 1.0 µl l^–1, or 2.0 µl l^–1, un-treated fruit served as controls. Each 1-MCP treatment was applied for 24 h at 20°C. After treatment, fruit were transferred to ambient temperature storage (22º ± 4ºC; 65 – 70% relative humidity) for 18 d, during which time observations on various physical, physiological, and biochemical parameters were recorded at 3 d intervals. Our results indicated that 2.0 µl l^–1 1-MCP was the most effective treatment to delay softening and ripening in ‘Allison’ kiwifruit, as such fruit showed the lowest mean weight loss (9.8 ± 0.2%), the highest mean fruit firmness value (32.7 ± 0.2 N), and began to ripen only after 12 d in storage, whereas untreated fruit started ripening on day-6 of storage. The activities of fruit softening enzymes such as polygalacturonase (PG; 58.5 ± 0.3 µg galacturonic acid g^–1 FW h^–1), and lipoxygenase (LOX; 3.96 ± 1.3 µmoles linoleic acid oxidised min^–1 g^–1 FW h^–1) were lower, and total phenolics (TP) contents (24.3 ± 0.3 mg 100 g^–1) and anti-oxidant (AOX) activities (12.5 ± 0.03 µmol Trolox g^–1 FW h^–1) were higher in 1-MCP-treated fruit than in untreated fruit (PG, 98.3 ± 0.5 µg galacturonic acid g^–1 FW h^–1; LOX, 4.39 ± 1.0 µmoles min^–1 g^–1 FW h^–1; TP, 5.3 ± 0.6 mg 100 g^–1; AOX, 4.7 ± 0.02 µmol Trolox g^–1 FW h^–1, respectively). In addition, 1-MCP-treated fruit exhibited lower rates of respiration (48.3 ± 0.4 ml CO₂ kg^–1 h^–1) and ethylene production (30.2 ± 0.02 µl kg^–1 FW h^–1) than untreated fruit (58.9 ± 0.6 ml CO₂ kg^–1 h^–1; 38.7 ± 0.04 µl kg^–1 FW h^–1, respectively). Similarly, 1-MCP-treated fruit had higher titratable acidity (TA; 1.33 ± 0.3%) and ascorbic acid (AA) contents (115.9 ± 2.6 mg 100 g^–1 pulp) and lower soluble solids contents (SSC; 8.33º ± 0.2º Brix) than untreated kiwifruit (TA, 1.0 ± 0.2 %; AA, 105.3 ± 2.2 mg 100 g^–1 pulp; SSC, 13.7º ± 0.3º Brix, respectively). Thus, 2.0 µl l^–1 1-MCP can be used for the post-harvest treatment of ‘Allison’ kiwifruit to enhance its shelf-life and marketability by approx. 6 d.     

Effects of 1-aminocyclopropane carboxylic acid on the rate of ethylene release from detached fruiting spurs and on fruit abscission in apple

Summary

1-Aminocyclopropane carboxylic acid (ACC) was applied to apple (Malus × domestica Borkh.) trees or to individual fruiting spurs between full bloom (FB) and 31 d after full bloom (DAFB; mean fruit diameter of 20 mm) to determine the effects of ACC on the ethylene released from detached spurs and on fruit abscission. The rate of ethylene release from detached fruiting spurs increased 1 d after applying 50 mg l^–1 ACC at full bloom or 16 DAFB (mean fruit diameter of 10 mm), but ACC had a reduced effect on the rate of ethylene release when it was applied 31 DAFB (mean fruit diameter of 20 mm). ACC reduced fruit set in ‘GoldRush’ apple in a concentration-dependent manner in 2009 and in 2010, but had no thinning activity on ‘Pink Lady’ in 2010. ACC at 200 mg l^–1 resulted in the yellowing and abscission of ‘GoldRush’ spur leaves in 2009, but not in 2010. The effects of combining ACC and 5 mg l^–1 naphthaleneacetic acid on fruit set in ‘GoldRush’ apple were additive. The application of 200 mg l^–1 ACC when fruit are ca. 10 mm in diameter may therefore be a useful chemical thinning treatment for apple fruit.     

Physiological and physico-chemical changes in green papaya (Carica papaya L. ‘Kaek Noul’) shreds taken from the outer or inner mesocarp

This study compared physiological and physico-chemical changes in shreds of green papaya (Carica papaya L. ‘Kaek Noul’), taken from inner and outer mesocarp tissues, during storage at 7ºC for up to 8 d. Reductions in the flesh firmness of shreds, microstructure, colouration, dry matter content (DMC), and fresh weight (FW) loss, and in the rates of respiration, ethylene production, and enzyme activities were measured. The rapid loss of firmness of green papaya ‘Kaek Noul’ shreds taken from the inner mesocarp was attributed to the larger and more loosely arranged cells of the inner mesocarp compared to the smaller and compact cells of the outer mesocarp. Shreds taken from the outer mesocarp had a higher DMC [6.21–6.77% (w/w)] than those from the inner mesocarp [5.83–6.34% (w/w)] during storage at 7ºC. FW loss was higher for shreds from the inner mesocarp than from the outer mesocarp (0.89–1.12% vs. 0.39–1.00%, respectively). Colour values (h°) were lower at the end of storage for shreds from the inner mesocarp than shreds from the outer mesocarp (104.38° and 111.94°, respectively). Moreover, scanning electron micrographs of shreds from inner mesocarp and outer mesocarp tissues showed that the slower loss of firmness in shreds from the outer mesocarp could be attributed to having smaller and more compact cells, as well as to lower ethylene production by the outer mesocarp. However, this was not related to cellulase activity. This study indicated why processors prefer to use shreds from the outer mesocarp of green papaya.     

Techniques for manipulation of the annual growth cycle in raspberry

Summary

Walnut (Juglans regia L.) leaves provide a source of healthy compounds, phenolics, which could be useful for the prevention of diseases in which free radicals are involved. In this study, walnut leaves from 14 different cultivars were studied for their total phenolics contents and anti-oxidant activities. Anti-oxidant activities were evaluated by measuring the scavenging activities of leaf extracts against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals. The total phenolics contents of the cultivars ranged from 17.7 mg gallic acid equivalents (GAE) g^–1 FW to 39.6 mg GAE g^–1 FW. The highest scavenging activities were found in methanol extracts of walnut leaves. Total phenolics contents were highly correlated with anti-oxidant activity (R²= 0.94 – 0.92).     

Differences in ovary size among olive (Olea europaea L.) cultivars are mainly related to cell number,not to cell size

Differences in mature fruit size among olive cultivars are related to differences in ovary size at bloom, but it is not known whether cell number or size determines the variation in ovary size. In this study we measured cell size and number in equatorial cross-sectional areas of the principal ovary tissues (mesocarp and endocarp) in eight cultivars with very different fruit and ovary size. The results showed that cell number explained most of the differences in ovary size, while cell size was not related to ovary size, except for a weak (R² = 0.33) correlation in the endocarp. Since sink strength is thought to be related to cell number, this finding supports the hypothesis that larger ovaries represent stronger sinks. The implications of greater sink strength with bigger ovaries are discussed. Within cultivars, while the cross-sectional areas of mesocarp and endocarp were similar, cell number was higher in the mesocarp but cell size was smaller compared to the endocarp.     

桃果实缝合线软化过程中内源激素的变化

为了明确桃果实缝合线过早软化的原因,以大久保桃为试材,利用气质联用和高效液相色谱的方法,对缝合线软化果(障碍果)和正常果的种仁、缝合线处果肉和其它部位果肉中的生长素(IAA)、玉米素(Z)、脱落酸(ABA)、茉莉酸(JA)的浓度进行了测定分析。结果表明,果肉ABA浓度是种仁的8～9倍,并随着果实的发育逐渐增加,接近成熟时达到最高,主要表现出对果肉成熟的调控作用。障碍果中Z的浓度在内果皮硬化初期明显高于正常果,与其缝合线异常生长(凸起)吻合;障碍果种仁的IAA浓度在内果皮硬化初期明显低于正常果,果肉中IAA浓度在内果皮硬化后上升,且障碍果高于正常果,说明IAA对中果皮细胞的扩大与成熟软化起调控作用。JA在种仁中的浓度是果肉的3～6倍,在硬核初期障碍果明显低于正常果,到硬核结束时则高于正常果,推测可能JA与内果皮发育有关。     

Influence of temperature on selenium and sulphur accumulation in Brassica oleracea L.

Summary

Selenium (Se) and sulphur (S) accumulation are affected by many factors in plants. To understand how growing temperature affected Se and S uptake and accumulation in Brassica oleracea, plants were grown at three different temperatures: 10°, 20° and 30°C. Plant growth, as reflected in fresh weight (FW) and dry weight (DW), increased with increasing temperature. Se and S accumulation were temperature-dependent and tissue-specific. Se levels increased linearly with increasing temperature in the leaves, and varied from 1.73 – 2.54 mg Se g^–1 DW. Conversely, Se accumulation decreased linearly with increasing temperature in the roots, and varied from 2.17 – 2.87 mg Se g^–1 DW. Growing temperature significantly affected S accumulation in leaves, but not in shoots or in roots. Sulphur levels ranged from 20.83 – 30.98 mg g^–1 DW in leaves, and increased with higher temperatures. Sulphate accumulation was similar to S, except that accumulation decreased at the highest growing temperature. Vegetables that accumulate S can be an efficient means and an effective alternative to deliver Se in human diets. To ensure that optimal levels of Se are attained in plants, without negative effects on plant productivity, factors that affect uptake and accumulation, such as growing temperature, need to be better understood.     

Changes of abscisic acid and its metabolite during development of apple fruit

Summary

Free and conjugated abscisic acid (ABA) and phaseic acid (PA) concentrations in the seed and pulp of apples (Malus pumila Mill. cv. Tsugaru) and ABA metabolism in the fruit after cis-(+)-ABA application were investigated. In the seed, the levels of cis- and trans-ABA and conjugated cis- and trans-ABA showed a general increase towards harvest, except for the decrease of cis-ABA at 131 d after full bloom (DAFB) (harvest). PA levels reached a peak at 41 DAFB, then decreased until harvest. The levels of free ABA in the seed were higher than those in the pulp. In the pulp, the levels of cis-ABA increased gradually from 20 DAFB and rapidly from 111 DAFB towards harvest. The levels of trans-ABA and conjugated trans-ABA also showed similar changes to cis-ABA, i.e. increased steeply from 111 DAFB. In contrast, the level of conjugated cis-ABA was the highest at 20 DAFB, then fell rapidly until 111 DAFB and then increased again towards harvest. PA showed the highest level at 20 DAFB, then decreased gradually until 111 DAFB and then increased again towards harvest. It is therefore assumed that not only cis-ABA but also its metabolite may be associated with the ripening of apple fruit. Cis- and trans-ABA and conjugated cis- and trans-ABA concentrations in cis-(+)-ABA treated fruit increased significantly on 11 d after ABA application (122 DAFB). However, at 20 d after cis-(+)-ABA application, only trans-ABA and conjugated trans-ABA showed higher levels than those of the untreated control, while the levels of cis-ABA and conjugated cis-ABA fell to the same levels as the untreated control. PA levels did not show significant increase on 11 and 20 d after cis-(+)-ABA application. These results suggest that cis-(+)-ABA treated exogenously to apple fruit may eventually metabolize to trans-ABA, conjugated trans-ABA and further metabolites.     

‘紫红1 号’红肉苹果果肉抗氧化性及花色苷分析

 ‘紫红1号’是新疆红肉野苹果[Malus sieversii f. neidzwetzkyana（Dieck）Langenf.]与‘富士’苹果杂交的F₁代中的一株果肉全红的株系。以其为试材,测定其果肉的花色苷、多酚、类黄酮含量及其抗氧化能力,结果表明其果肉花色苷含量为228.3 mg · kg^-1 FW,总酚含量为2 523 mg · kg^-1 FW,类黄酮含量为2 514 mg · kg^-1 FW,其抗氧化能力（ferric reducing antioxidant power,FRAP）为13.39 μmol · g^-1。利用液质联用（UPLC-PAD-/MS/MS）鉴定了红肉苹果果肉花色苷的主要组分有9种,其中4种分别为矢车菊3–O–葡萄糖苷、矢车菊3–O–半乳糖苷、矢车菊3–O–木糖苷、矢车菊3–O–阿拉伯糖苷,其中矢车菊3–O–半乳糖苷占73.37%,另外5种暂不能确定其结构。本研究表明花色苷的稳定性,发现该色素在pH 1 ~ 3,40 ℃以下比较稳定,高温加速花色苷的降解。花色苷对光照敏感,暴露在室内自然光下15 d其残留率为41.53%。     

Flowering and fruiting phenology,and physico-chemical characteristics of 2-year-old plants of six species of Opuntia from eight regions of Morocco

SUMMARY

We have described the flowering and fruiting phenology of 14 accessions of six Opuntia species grown in Morocco: O. ficus-indica, O. robusta, O. aequatorialis, O. dillenii, O. leucotricha, and O. stricta. We also determined the physicochemical characteristics of their cladodes. For each accession, we used four-to-20 plants. Two systems were used to measure phenology: the extended Biologische Bundesanstalt, Bundessortenamt und Chemische Industrie (BBCH)-scale and the National Phenology Monitoring System. Five principal stages were described: the development of vegetatively-propagated organs (vegetative buds), the development of flower buds, flowering, fruit development, and fruit maturity. The number of vegetative buds varied significantly among the 14 accessions, while only four accessions produced flower buds. After reaching their final size, fruit lengths varied from 3.40–6.40 cm, while fruit diameters varied from 1.93–3.90 cm. The average cladode number differed significantly among genotypes and varied from 1.75–7.75. There were also significant differences in cladode length (13.75–30.63 cm), width (6.25–17.33 cm), thickness (0.65–1.38 cm), fresh weight (FW; 67.50–766.00 g), and dry weight (DW; 8.75–67.15 g) between species. Water content and ash content, as well as total protein and total sugar concentrations, showed significant differences and were within the ranges of 86.67–92.04% (w/w), 12.97–22.08g 100 g^?1 DW, 4.64–11.56g 100 g^?1 DW, and 3.22–12.51 g 100 g^?1 DW, respectively. Our results will help in the development of agronomic management practices and improve the characterisation, valorisation, and use of cactus pear species grown in Morocco.     

Early growth and development of the olive fruit mesocarp

SUMMARY

We examined growth and development of the ‘Manzanilla’ olive fruit mesocarp in transverse equatorial sections during the first 12 weeks after full bloom (AFB). Sequential sampling and quantitative data provided an integrated view of the formation of this tissue. The mesocarp, or fruit flesh, was formed by relatively isodiametric parenchyma cells with a small number of isolated sclereids. By four weeks AFB a gradient in cell size characteristic of mature olive fruits began to appear. Biweekly measurements of cell size and number indicated that, as in other drupes, both cell division and expansion contribute to initial mesocarp growth. From six weeks AFB, further mesocarp growth was determined solely by cell expansion. Transverse areas of mesocarp and endocarp, also measured biweekly, revealed that both tissues expand in a similar manner until eight weeks AFB, after which mesocarp growth predominated.     

Effects of cultivar,orchard elevation,and storage on fruit quality characters of sweet cherry (Prunus avium L.)

Fruit quality characters were analysed in the sweet cherry cultivars, Burlat, Van, Tragana and Mpakirtzeika, harvested from low (39–59 m), medium (216 m) or high (490–546 m) elevation sites. The effects of storage for 2 or 4 days at 2 °C and 1 day at 20 °C on the fruit antioxidant contents were also evaluated. Tragana and Mpakirtzeika had greater fruit fresh weight (FW) and total soluble solid content compared to Van and Burlat, the latter being the most red colored. Tragana and Burlat had greater total phenolic content and total antioxidant capacity, measured by DPPH extinction, compared to Mpakirtzeika and Van (mean values 204.4 mg vs. 103.7 mg gallic acid equivalent 100 g⁻¹ FW, and 176.1 mg vs. 79.3 mg ascorbic acid equivalent 100 g⁻¹ FW, respectively). The geographic elevation had a marked influence on the cherry antioxidant content in all studied cultivars, apart from Van, with high elevation orchards producing cherries with greater contents of antioxidant compounds compared to lower elevation orchards. Changes in the antioxidant contents during storage were depended on the cultivar and some times on the orchard elevation. Total antioxidant capacity was significantly correlated with total phenolic content in Tragana, Burlat and Mpakirtzeika, but not in Van; nevertheless this was not the case during storage.     

Enhanced production of bioactive ginsenosides from adventitious roots of Panax ginseng in bioreactor culture

Summary

Panax ginseng C.A. Meyer roots are highly prized in international markets for their medicinal properties. The present study focussed on the enhanced production of the bioactive anti-cancer protopanaxatriol group of ginsenosides in adventitious roots of P. ginseng in bioreactor cultures by feeding the biogenetic precursor, squalene. HPLC-MS analysis of the saponin fraction indicated higher accumulation of the protopanaxatriol group of ginsenosides (Rg₁ 0.96 mg g^–1,Rg₂ 0.09 mg g^–1 and Re 1.91 mg g^–1 DW) in 40 d-old squalene-fed adventitious roots compared to controls. The results allow predictions of the biosynthetic pathway from squalene to ginsenosides in adventitious roots.     

Profiling nutraceuticals in bael [Aegle marmelos (L.) Correa] at various stages of fruit development

Bael [Aegle marmelos (L.) Correa], a medicinally important fruit tree grown on the Indian sub-continent, contains two bio-active furanocoumarins, marmelosin and psoralen, with pharmacological properties, plus two powerful groups of natural anti-oxidants, polyphenols and tannins. The present investigation aimed to measure the levels of these nutraceuticals at various stages of fruit development [150–345 days after fruit set (DAFS)] in two promising selections of bael from the Institute, CISH B-1 and CISH B-2, using a simple high performance liquid chromatography (HPLC) technique. Marmelosin and psoralen were extracted from 5 g of homogenised fruit mesocarp using benzene, while tannins were extracted as tannic acid with 80% (v/v) methanol in water. Polyphenol concentrations were measured spectrophotometrically at 760 nm using Folin-Ciocalteu reagent. The concentrations of marmelosin declined from 1,660 and 726 µg g^?1 at 150 DAFS, to 523 and 170 µg g^?1 at 345 DAFS in CISH B-1 and CISH B-2, respectively, whereas psoralen concentrations decreased from 216 and 41 µg g^?1 to 102 and 9 µg g^?1 during the same growth period in CISH B-1 and CISH B-2, respectively. Tannic acid concentrations decreased from 1.65 and 2.02 g 100 g^?1 at 150 DAFS, to 1.52 and 1.54 g 100 g^?1 at 345 DAFS in CISH B-1 and CISH B-2, respectively. The concentrations of total polyphenols did not show any significant changes in either bael selection over the same growth period. The concentrations of marmelosin and psoralen in CISH B-1 were highest in October (150 DAFS), while these values peaked in November (190 DAFS) in CISH B-2. The results suggest that fruit harvested at an early stage of growth (October–November) contained higher concentrations of nutraceuticals, increasing their suitability for fruit processing and use in the phyto-pharmaceutical industries.     

红肉桃果实发育过程中色素和糖酸含量的变化

以红肉、白肉和黄肉3种不同果肉颜色的12份桃品种为材料分析成熟时果肉中花色苷的含量变化,结果表明,红肉桃与白肉、黄肉品种间花色苷含量差异显著,且红肉桃品种间的花色苷含量差异也很大。利用3个不同果肉颜色的桃品种进一步研究果实发育过程中色素及其相关物质的变化,结果表明,红肉桃品种天津水蜜在盛花后25d果肉中花色苷含量较高,而后逐渐减少;直至进入盛花后45d才缓慢回升,并在果实发育后期(盛花后86d)含量迅速增加;与此对应,该品种果皮在幼果期(盛花后35～45d)和果实发育后期(盛花后86d)2次出现红色,但果肉直到盛花后86d才明显变红;在整个果实发育过程中,天津水蜜果肉其它内含物的变化与白肉桃品种豫白和黄肉桃品种NJC83相似:叶绿素含量逐渐减少;类胡萝卜素和可溶性糖不断增加;可滴定酸前期上下波动变化,但近成熟时天津水蜜的可滴定酸显著高于其它2个品种。     

The effects of Apogee® on shoot growth,secondary flowering,fire blight,fruit quality,yield and return bloom in ‘Bartlett’ pear growing in California

Summary

Apogee^® sprays were applied to mature ‘Bartlett’ pear (Pyrus communis L.) trees as single or multiple sprays during the growing seasons of 1999 to 2003 at concentrations of 420 g ha^–1 (125 mg ^–1) or 840 g ha^–1 (250 mg^–1): both reduced vegetative shoot growth. Two sprays of 840 g ha^–1 applied 3–3.5 weeks apart were most effective and reduced shoot growth by approximately 40%. An application made 2 d after fall bloom was ineffective and led to more vegetative shoot growth. Single sprays of Apogee^® made within 9–28 d after full bloom (DAFB) were equally effective in reducing vegetative shoot growth. Bourse shoot growth was reduced 43% by 3 April, 2001 (8 DAFB) treatment of 840 g ha^–1 when bourse and vegetative shoots ranged from 2.5 to 7.5 cm in length. Subsequent single applications of 840 g ha^–1 Apogee^® (on April 12 or 23, 2001) did not reduce bourse shoot growth significantly. Vegetative shoot growth was also reduced by 12% (9 d after treatment) and by 38% (approximately one month after treatment) by 840 g ha^–1 Apogee^® applied on 3 April, 2001, (8 DAFB). In 2002, bourse shoot growth was controlled most effectively by split applications (840 + 420 g ha^–1 or 840 2 g ha^–1, 9 April and 24 May) and by 840 g ha^–1 Apogee^®, applied at 2.5 to 7.5 cm shoot growth (9 April). These split applications, as well as girdling, decreased shoot strikes in 2002, the year after treatment. Split applications of 840 g ha^–1 Apogee^® made in April to early May were most effective in controlling both vegetative and bourse shoot growth in most years, although single applications of Apogee^® were effective in some years. Subsequent flushes of shoots tended to be controlled by split applications with the second application timed to the emergence of new shoots. Apogee^® was not consistently effective in reducing the incidence of Type I or Type V secondary flowers in these trials. Single or multiple sprays of Apogee^® had no measurable or consistent effect on return bloom, fruit size or shape, firmness, percentage soluble solids, or yield per tree over the period of these experiments. Apogee^® appears to have promise as a shoot growth control agent in ‘Bartlett’ pear growing in California, USA, without deleterious effects.