果实膨大期喷布磷酸二氢钾对三月红荔枝果实贮藏性的影响

在三月红荔枝(Litchi chinensis cv.Sanyuehong)果实膨大期对树冠喷施0.2%磷酸二氢钾(KP)水溶液,以探讨磷酸二氢钾对荔枝果实贮藏性的影响。结果表明:(1) KP处理的果实在贮藏期前17d,失重率及果肉可溶性固形物、酸、VitC、花色素苷等指标的变化趋势与对照基本相似;(2) KP处理的果肉可溶性蛋白质含量变化与对照有明显差异,而果皮的可溶性蛋白质含量在贮藏期前10d变化动态与对照一致,此后呈相反的变化趋势;(3)果皮POD活性显著高于果肉,KP处理和对照的果肉POD活性在贮藏第3d后、果皮POD活性在第17d前分别具有相似变化趋势;(4)果肉中CAT活性在贮藏第3~17d期间都显著或极显著高于果皮,KP处理和对照果肉、果皮CAT活性动态变化均为单峰曲线。     

新红星苹果果实着色期几种色素含量变化及其相关性（简报）

新红星苹果果实在果皮着色前果皮内叶绿素、类胡萝卜素含量降至最低。果皮着色过程中,随果皮内花青素含量迅速增加,叶绿素及类胡萝卜素含量也出现增加趋势,果色由淡红变为深红。自然着色前在果皮伤害处理情况下可明显刺激果皮内花青素、叶绿素、类胡萝卜素含量的一致提高。     

不同颜色果袋对‘云红梨2号’果皮色泽形成的影响

研究了不同颜色果袋对‘云红梨2号’果实着色的影响,比较了不同套袋处理下果皮外观着色、叶绿素、类黄酮、总酚、花色素苷含量以及花色素苷合成相关酶活性的差异.结果表明: 发育期的黑暗处理有利于解袋后梨果皮着色;不同套袋处理中,采前解袋自然光照射下梨果皮中花色素苷含量最高,着色最好,白色纸袋次之.不同套袋处理显著影响果皮中叶绿素、类黄酮、总酚和花色素苷含量,从而影响梨果皮的外观色泽.不同套袋处理的花色素苷合成酶活性差异显著;相关性分析表明,果皮中花色素苷含量与二氢黄酮醇-4-还原酶(DFR)和类黄酮3-O-葡萄糖基转移酶(UFGT)活性呈显著正相关,而与苯丙氨酸解氨酶(PAL)活性相关性不显著.     

紫娘喜荔枝果皮K、Ca和Mg含量变化对着色的影响

为探讨紫娘喜荔枝(Litchi chinensis)着色与果皮K、Ca和Mg含量变化的关系,以紫娘喜荔枝果皮为试材,通过对数据作典型性相关和一元指数函数回归分析,研究其K、Ca、Mg含量变化及其对叶绿素、花色素苷等含量的影响特点。结果表明:随着果皮不断转红,叶绿素含量呈显著下降趋势,而花色素苷含量却呈显著上升趋势;全K、水溶性K和全Ca、水溶性Ca含量分别呈下降和上升的趋势,水溶性Mg含量呈上升趋势,全Mg含量变化不显著,同期全K、Ca、Mg和水溶性K、Mg、Ca等含量分别呈依次递减趋势;花色素苷含量与全Ca和全K含量分别呈正和负相关的一元指数函数回归关系;叶绿素含量与水溶性Mg、全Ca和全K含量分别呈负、负和正相关一元指数函数回归关系。可见,全Ca含量较高是促进果皮转红的关键因素,研究结果可为制定紫娘喜荔枝合理施肥技术提供理论依据。     

外源ABA和GA3对红肉脐橙果皮主要色素含量变化和果实着色的影响

测定了红肉脐橙(Citrus sinensis Osbeskcv.CaraCara)果实发育期间和果实转色前用不同浓度的外源ABA和GA₃处理后果皮叶绿素和类胡萝卜素的动态含量,并测定了外源ABA和GA₃处理后成熟红肉脐橙果皮色泽的表现。结果表明:红肉脐橙果皮叶绿素含量于9月20日出现最大值,为0.1469mg·g^-1FW;类胡萝卜素含量于12月20日达到最大值,为0.0321mg·g^-1FW;果实转色前,用外源ABA处理后加速了果皮叶绿素的降解,但也抑制了果皮类胡萝卜素的积累,用GA₃处理后延缓了果皮叶绿素的降解,同样抑制了果皮类胡萝卜素的积累,严重阻碍了果皮类胡萝卜素的合成;外源ABA或GA₃处理均不利于果实色泽品质的提高。     

外源L-谷氨酸对荔枝果实生长与着色以及营养品质的调控作用

以8年生‘妃子笑’荔枝为试验材料,于盛花后45d果面喷施0、1.10、1.30、1.50、1.70和1.90g/L的L-谷氨酸,研究各浓度L-谷氨酸处理对‘妃子笑’荔枝果实生长、果皮着色和果肉营养品质的影响。结果显示:(1)各浓度L-谷氨酸处理对采收期(处理后20d)荔枝果皮中的叶绿素含量无显著影响,但1.30~1.90g/L L-谷氨酸处理采收期荔枝果皮中花青苷含量比对照显著增加92%以上;在采收期,1.10~1.30g/L L-谷氨酸处理的果面色泽参数a*值显著高于对照,色度角h°值、亮度L*、色彩饱和度C值均显著低于对照。(2)与对照相比,1.10g/L L-谷氨酸处理使采收期荔枝果实单果重、纵径和横径分别显著增加30%、4%和6%,而1.90g/L L-谷氨酸处理的单果重、纵径和横径分别比对照降低了1%~2%。(3)L-谷氨酸(1.10、1.30和1.70g/L)处理使荔枝果肉可溶性固形物含量峰值的出现时间比对照延迟5d,缩短了果皮与果肉的发育间隔时期;各浓度L-谷氨酸处理对果肉可滴定酸含量无显著影响,但1.30g/L L-谷氨酸处理使荔枝果肉中维生素C含量比对照提高15%。研究表明,适宜浓度的外源L-谷氨酸处理可显著促进‘妃子笑’荔枝果实生长和果皮着色,并有效改善果肉营养品质,其中以1.30g/L L-谷氨酸处理的综合效果最好,过高浓度L-谷氨酸(1.90g/L)则抑制荔枝生长。     

外源ALA对克瑞森无核葡萄叶片光合特性及果实品质的影响

以日光温室栽培的欧亚葡萄品种克瑞森无核为试验材料,在果实膨大期和始熟期采用不同浓度(50、100和150mg·L~(-1))5-氨基乙酰丙酸(ALA)喷施叶片和果穗,研究外源ALA处理对葡萄叶片光合特性、果实着色效果及果实品质的影响。结果表明:(1)各浓度ALA处理后葡萄叶片胞间CO_2浓度(Ci)、气孔导度(Gs)、蒸腾速率(Tr)、净光合速率(Pn)都有不同程度的增加,并以100mg·L~(-1) ALA处理效果最好。(2)50~150mg·L~(-1) ALA处理均能不同程度提高葡萄果皮花青素、叶绿素及类胡萝卜素含量,且各ALA处理的果实可溶性糖含量显著高于对照,但可滴定酸含量低于对照。(3)100和150mg·L~(-1) ALA处理能够显著改善果实成熟期的着色参数,且果实着色指数(CIRG)与花青素的积累呈现出良好的一致性。研究发现,在葡萄果实膨大期及始熟期喷施适宜浓度(100mg·L~(-1))ALA能够有效提高叶片光合性能,同时促进果实着色,显著改善果实外观色泽和果实品质。     

外源脱落酸对桃果实着色及相关基因表达的影响

以‘美香’桃为试验材料,于果实着色前用1 000、500、300mg/L的脱落酸(ABA)溶液处理果实,研究了ABA处理促进桃果皮着色的效果以及对果皮花色素苷合成相关基因表达的影响。结果表明:ABA处理显著提高了成熟果实可溶性固形物含量和果皮花色素苷含量;明显改善了果实着色,且以1 000mg/L效果最为明显。ABA处理显著促进了查尔酮合成酶基因(CHS)和二氢黄酮醇4-还原酶基因(DFR)的前期转录水平,同时促进了类黄酮葡萄糖苷转移酶基因(UFGT)和花色素合成酶基因(LDOX)表达高峰的前移。据此推测ABA可能参与了桃果实花色素苷合成的调控,对花色素苷合成具有促进作用。     

桃树体不同部位果实着色差异及其与环境因子的关系研究

为探讨树体冠层不同部位桃果实着色机制差异及其与环境因子的关系,以晚熟桃品种‘霞晖8号’为试材,研究了果实3个典型发育时期(硬核期、膨大期、成熟期)树体冠层上部、中部外围、中部内膛和下部的温度、光照环境因子变化动态,并就其对果皮色泽、色素含量的影响及与果实着色相关的基因表达特点进行解析。结果表明:(1)与冠层下部果实相比,‘霞晖8号’冠层上部、中部外围和中部内膛成熟果实果皮a~*/b~*(红色饱和度/黄色饱和度)显著较高。(2)冠层下部成熟果实的果皮花色素苷含量最低而叶绿素含量最高,且与其他部位间差异显著。(3)果实不同发育时期花色素苷合成相关基因的表达量差异表明,果皮花色素苷合成是多基因协同调控的过程。(4)果实转色前,低光照强度抑制了花色素苷合成相关基因的表达,其中对UFGT、DFR、CHS基因的调控作用最明显;果实成熟期,与高光照条件相比,低光照条件下果皮花色素苷合成相关基因上调表达。研究认为,树体冠层不同部位光照条件差异可能是导致果实着色差异的主要环境因素之一,它通过调节与果皮花色素苷积累相关的基因表达水平控制果皮的着色。     

套袋对苹果发育过程中果皮色素及果肉糖含量的影响

以富士苹果'长富2号'品系为试材,研究了套袋后果实生长发育过程中果皮色素含量、果肉糖含量及取袋后果皮色素、糖含量和PAL活性等品质形成因子的变化规律.结果显示:套用双层纸袋能显著降低红富士苹果果皮叶绿素含量,并以叶绿素a降低幅度较大,且与总叶绿素含量呈基本一致的下降变化趋势,而果皮类胡萝卜素降低幅度较小;果皮的花青苷含量取袋前显著低于对照,取袋后迅速上升,并在取袋后6 d超过对照,采收时超过对照1倍以上;果实PAL酶活性取袋后呈先升后降的趋势,取袋后4 d活性超过对照,取袋后6 d活性达到最高值;套袋不同程度地降低了果实可溶性总糖和还原糖含量,取袋后可溶性总糖、果糖和葡萄糖含量上升,蔗糖含量在取袋后4 d内迅速上升而后下降,但套袋果始终低于对照果.研究表明,套袋可以显著降低果皮中叶绿素的含量,促进花青苷积累,从而减少叶绿素对果实着色的干扰,提高果实外观品质,但同时也部分减少了果实总糖的含量,对果实内在品质有一定负面影响.     

树冠覆膜对金柑光合作用及果实品质的影响

树冠覆膜技术已在金柑生产中得到广泛应用。该研究以阳朔金柑为材料,树冠覆膜作为处理,不覆膜作为对照,分别测定处理和对照的树冠的温度、湿度和光照强度等环境因子的变化,观测处理和对照的叶面积、叶长、叶宽及叶绿素含量,测定处理和对照的净光合速率、气孔导度、蒸腾速率和胞间二氧化碳浓度等光合作用指标,并分析处理和对照的果实硬度、可溶性固形物、总糖、可滴定酸及维生素C含量等果实品质指标。结果表明:与对照相比,金柑树冠覆膜处理后,树冠的光照强度降低、温度上升、湿度下降、叶面积增大、叶绿素含量提高,净光合速率下降且最大降幅是对照的21.39%,果实的可滴定酸降低,但硬度、可溶性固形物、总糖、固酸比及糖酸比等果实品质指标提高。金柑树冠覆膜处理减少了树冠的光照,降低了净光合速率,但增加了叶面积和叶绿素含量,从而保障了光合同化物的累积,提高了果实的可溶性固形物和总糖。同时,树冠覆膜处理还提高了树冠白天的气温,降低了可滴定酸,增大了固酸比和糖酸比,因此从总体上提高了果实品质。     

NO3-胁迫及恢复对黄瓜幼苗叶片叶绿素荧光参数及ATPase活性的影响

通过水培试验,探讨了不同NO₃^-浓度胁迫及恢复对黄瓜幼苗叶片叶绿素含量、叶绿素荧光参数及ATPase活性的影响.结果表明,胁迫7 d后,高浓度NO₃^-(168 mmol·L^-1)可极显著提高叶绿素a、叶绿素b、总叶绿素和类胡萝卜素含量,极显著提高初始荧光(F_o)、Mg ATPase和Ca-ATPase活性,而PSⅡ原初光能转化效率(F_v/F_m)、PSⅡ潜在活性(F_v/F_o)和PSⅡ光合电子传递量子效率(ΦPSⅡ),却随NO₃^-浓度的增加而降低.恢复7 d后,所有处理叶绿素和类胡萝卜素含量均低于对照;初始荧光基本都恢复至对照水平;PSⅡ原初光能转化效率和PSⅡ光合电子传递量子效率在NO₃^-浓度低于126 mmol·L^-1时,基本恢复至对照水平,而高于这一水平时,仍显著低于对照;PSⅡ潜在活性在NO₃^-浓度为42和126 mmol·L^-1的处理基本达对照水平,其它处理仍极显著低于对照;Mg-ATPase和Ca-ATPase活性均出现先降低后升高的变化趋势.     

Effects of anthocyanin and carotenoid combinations on foliage and immature fruit color of Capsicum annuum L

Shades ranging from violet to black pigmentation in pepper (Capsicum annuum L.) are attributed to anthocyanin accumulation. High-performance liquid chromatography and mass spectrometry analysis of violet and black fruit tissue identified a single anthocyanin that was determined to be delphinidin-3-p-coumaroyl-rutinoside-5-glucoside. Leaf tissue of a black-pigmented foliage genotype contained the same anthocyanin found in fruit but at a considerably higher concentration in comparison to violet and black fruit tissue. Fruit chlorophyll concentration was approximately 14-fold higher in black fruit in comparison to violet fruit that contained relatively little chlorophyll. Beta-carotene, lutein, violaxanthin, and neoxanthin carotenoid concentrations in black fruit were also significantly greater in comparison to violet fruit. High concentrations of delphinidin in combination with chlorophyll and accessory carotenoid pigments produced the characteristic black pigmentation observed in fruits and leaves of selected genotypes. Anthocyanins were accumulated in the outer mesocarp of violet and black fruit and in the palisade and mesophyll cells of black leaves. Consistent with chlorophyll content of respective genotypes, chloroplast density was greater in cells of black fruits. Utilizing Capsicum pigment variants, we determine the biochemical factors responsible for violet versus black-pigmented pepper tissue in the context of described pepper color genes.     

Study of 'Redhaven' peach and its white-fleshed mutant suggests a key role of CCD4 carotenoid dioxygenase in carotenoid and norisoprenoid volatile metabolism

Background  

Carotenoids are plant metabolites which are not only essential in photosynthesis but also important quality factors in determining the pigmentation and aroma of flowers and fruits. To investigate the regulation of carotenoid metabolism, as related to norisoprenoids and other volatile compounds in peach (Prunus persica L. Batsch.), and the role of carotenoid dioxygenases in determining differences in flesh color phenotype and volatile composition, the expression patterns of relevant carotenoid genes and metabolites were studied during fruit development along with volatile compound content. Two contrasted cultivars, the yellow-fleshed 'Redhaven' (RH) and its white-fleshed mutant 'Redhaven Bianca' (RHB) were examined.     

采后光照条件对白凤桃果实品质和挥发性香气物质形成的影响

研究了白凤桃果实贮藏过程中光照条件对果实成熟的影响。在7月12日(未熟期)和7月16日(硬熟期)采收果实,分别贮藏在光条件(白色荧光灯照明,果顶部光强为80μmol m~(-2)s~(-1))和暗条件中,室温均为25℃。硬熟期采收果实贮藏在光条件下,达到完熟期时,乙烯生成量较低。果肉的硬度在各个采收期,各种贮藏条件下均没有差别。光条件贮藏果实中花青苷含量较高。未熟期采收果实贮藏在光条件下时,可溶性固形物含量增加较多。光条件贮藏果实中天冬酰胺的下降比暗贮藏果实中更多。各时期采收的果实中,在光下贮藏时,果肉和果皮γ-癸内酯和γ-十二内酯的含量都明显增加。以上结果表明,白凤桃果实采收后在光下贮藏,可以明显改善果实的品质。     

Strategies for salmonid pigmentation

Well pigmented flesh is regarded second after freshness as one of the most important quality criteria for farmed Atlantic salmon ( Salmo salar ). The required redness of salmonid flesh has caused a steady increase of astaxanthin concentration in salmonid flesh from about 2–3 mg kg⁻¹ during the 1970s to above 6 mg kg⁻¹ today. An individual variation in flesh pigmentation of more than 100% is experienced under practical as well as experimental conditions. An individual variation of this magnitude makes the precision of carotenoid estimations low, and impairs comparisons of treatments. The present paper discuss the importance of standardisation of the experimental conditions in relation to the level of flesh pigmentation and to variation in populations with the main focus on the effect of fish size, flesh carotenoid concentration and environmental factors.     

Arbuscular mycorrhizal fungi enhance fruit growth and quality of chile ancho (Capsicum annuum L. cv San Luis) plants exposed to drought

The effect of arbuscular mycorrhizal fungi (AMF) and drought on fruit quality was evaluated in chile ancho (Capsicum annuum L. cv San Luis). AMF treatments were (1) Glomus fasciculatum (AMFG), (2) a fungal species consortium from the forest “Los Tuxtla” in Mexico (AMFT), (3) a fungal species consortium from the Sonorian desert in Mexico (AMFD), and (4) a noninoculated control (NAMF). Plants were exposed to a 26-day drought cycle. Fruit quality was determined by measuring size (length, width, and pedicel length), color, chlorophyll, and carotenoid concentration. Under nondrought conditions, AMFG produced fruits that were 13% wider and 15% longer than the NAMF treatment. Under nondrought conditions, fruit fresh weight was 25% greater in the AMFG treatment compared to the NAMF. Under drought, fruits in the AMFT and AMFD treatments showed fresh weights similar to those in the NAMF treatment not subjected to drought. Fruits of the AMFG treatment subjected to drought showed the same color intensity and chlorophyll content as those of the nondroughted NAMF treatment and carotenoid content increased 1.4 times compared to that in the NAMF not exposed to drought. It is interesting to note that fruits in the AMFD treatment subjected to drought and the NAMF treatment not exposed to drought reached the same size. AMFD treatment increased the concentration of carotenes (1.4 times) under nondrought conditions and the concentration of xanthophylls (1.5 times) under drought when compared to the nondroughted NAMF treatment.     

Effect of postharvest salicylic acid treatment on fungal decay and some postharvest quality factors of kiwi fruit

The effect of salicylic acid (SA) treatment at different concentrations on fungal decay and some quality factors of kiwi fruit (Actinidia deliciosa var. Hayward) in postharvest conditions were studied. Results experiment showed that SA at all applied concentrations inhibited grey mould growth. The SA application significantly decreased weight loss percentage and increased life storage fruits. Also, SA positively affected on postharvest quality factors including total soluble solids (TSS), titratable acidity (TA), antioxidant, ascorbic acid and pH value. It was observed that treated fruits with SA at concentration 5?mM had the highest TSS, TA, ascorbic acid and antioxidant content and it had the lowest decay and acidity. Thus, these results showed that SA has strong impact on postharvest decay and fruit quality of kiwi fruit.