设施桃果实品质发育生理研究

以设施栽培的曙光、早红珠、春捷为试材,研究了桃果实发育过程中,主要品质指标的变化动态。结果表明:维生素C、可溶性蛋白、果皮叶绿素和类胡萝卜素含量随着果实的发育呈下降趋势,总糖、可溶性固形物含量及糖酸比不断增加。可滴定酸、总糖、维生素C和类胡萝卜素含量均在果实接近成熟期迅速变化。果实中淀粉含量很低且呈下降趋势,只是在果实发育前期有所升高。果实中干物质含量变化在花后50d内变化趋势是由低到高,此后,三者呈现不规则变化。可溶性蛋白在果实内含量由高到低递减,前期降减程度最大,后期含量保持相对稳定,其变化规律与果实生长一致。     

CPPU处理猕猴桃常温贮藏过程中果实糖含量相关基因的表达分析

为了解析采前CPPU处理的猕猴桃果实贮藏性与未处理果实的差异及相关的分子调控机制,以清水为对照,评价了盛花后用20 mg/L CPPU处理果实在常温贮藏下可溶性固形物、可滴定酸及可溶性糖含量的变化,并用转录组分析鉴定出与可溶性糖变化相关的候选基因。结果表明,无论处理还是对照,可溶性糖含量在贮藏过程中呈逐渐上升趋势,但CPPU处理果实的可溶性糖含量始终低于对照果实。转录组分析表明,CPPU处理抑制了淀粉和蔗糖代谢中的基因Achn087691(编码磷酸己糖异构酶)以及果糖和甘露糖代谢中基因Achn203191(编码磷酸丙糖异构酶)的表达,并促进淀粉和蔗糖代谢中基因Achn069851(编码己糖激酶)前期表达,但对基因Achn161931(编码尿苷二磷酸葡萄糖脱氢酶)、基因Achn206141(编码尿苷二磷酸-葡萄糖醛酸酯-4-表异构酶)和基因Achn295291(编码果胶甲酯酶)表现为前期抑制、中期促进、后期抑制。由此推测,20 mg/L CPPU处理明显影响了徐香猕猴桃果实中可溶性糖含量及糖代谢相关基因的表达,致使果实常温贮藏过程中可溶性固形物和可溶性糖含量降低,且提前软化。     

不同水分下桃果实细胞内糖酸分布特征分析

为研究不同水分对桃果实细胞内糖酸分布的影响,以成熟白凤桃果实为试验材料,研究了2个土壤水分水平( W1：田间持水量的60%~70%,W2：田间持水量的75%~85%)对果肉细胞内可溶性糖(蔗糖、葡萄糖、果糖和山梨醇)和有机酸(苹果酸、柠檬酸、奎宁酸和莽草酸)在液泡、细胞质与细胞间隙中含量的影响。结果表明, W1处理桃果实液泡、细胞质和细胞间隙中可溶性糖分别为39．47,16.73,13.03 mg/g,有机酸分别为4.38,3.15,0.69 mg/g,而在W2处理中可溶性糖分别为35.63,16.11,13.33 mg/g,有机酸分别为4.00,3.27,0.65 mg/g,表明增加水分供应可降低液泡中可溶性糖与有机酸含量。各种糖、酸组分透过细胞膜的渗透速率均高于液泡膜,随着土壤水分含量升高果实中糖、酸通过细胞膜与液泡膜的渗透速率有所降低。     

光对红肉桃果肉红色形成的影响

为探讨光照是否影响红肉桃果实果肉着色,以青岛市地方红肉桃品种“大把撸”为材料,研究了不同套袋处理对着色后红肉桃果肉糖酸及色素尤其是花青苷含量变化的影响。结果表明：套袋明显抑制了果肉红色的形成;果实摘袋见光后花青苷合成能力得到恢复;套袋也降低了红肉桃果肉可滴定酸、可溶性糖、叶绿素和类胡萝卜素含量,由此证明红肉桃果实果肉红色形成在很大程度上受光照影响。     

桃果实采后生理研究及贮藏保鲜技术应用进展

综合论述了桃果实在采后成熟衰老过程中发生的生理变化特点和贮藏保鲜技术情况。详细论述了桃果实采后呼吸强度、乙烯变化、酶含量、可溶性固形物含量、酸含量、VC含量变化规律,探讨了桃果实在采前、贮前和采后的贮藏保鲜方法。     

不同贮藏温度对蓝莓果实贮藏特性的影响

为研究不同温度下不同品种蓝莓果实的贮藏特性,以天津蓟州区主栽的8个蓝莓品种为试材,分别在10、4、0、-1℃贮藏条件下比较了果实的5个贮藏特性动态变化。结果表明,在4种贮藏温度下,温度越低,蓝莓果实好果率越高,失重率越低,硬度及可溶性糖含量的下降率越低,可溶性固形物含量保持越好。在10℃贮藏过程中,随着贮藏时间的延长,好果率逐渐降低,失重率逐渐增加,贮藏至14 d时,蓝莓的好果率在23.33%～85.33%,失重率在13.37%～27.40%;4℃贮藏过程中,好果率随时间延长逐渐降低,而失重率逐渐增加,贮藏至至21 d时,好果率在19.67%～69.50%,失重率在21.74%～35.66%;0℃和-1℃条件下,可溶性固形物含量均呈现先上升后下降的趋势,贮藏至70 d时,好果率在57.60%～95.67%,失重率在4.98%～17.72%,硬度较初值下降了20.69%～57.67%,可溶性固形物含量较初值下降了1.82%～61.71%,可溶性糖含量较初值下降了14.12%～42.17%。隶属函数综合分析不同贮藏温度条件下耐贮藏品种为布里吉塔、蓝金、莱克西。综合比较各指标发现,不同品种蓝莓在-1～0℃下贮藏均可维持较好的果实商品性(好果率和失重率)和果实品质(硬度、可溶性固形物及可溶性糖含量)。     

不同桃品种的品质及加工特性评价分析

为构建不同品种桃的品质评价方法及加工特性评价体系,为桃果实的品种筛选、品质分析、贮藏加工提供参考依据,以10个品种的蒙阴蜜桃果实为试验材料,测定其感官性状、质构特性、营养品质及加工特性。结果表明,不同桃品种在感官性状、质构特性、营养品质及加工特性上存在差异,供试的10个桃品种中,白桃九号在质构特性、VC含量、糖酸比、固酸比、果汁特性等方面均具有优势,是既适合鲜食又适合加工的优良桃品种;新世纪、黄金绣的果皮硬度、可溶性固形物含量和果汁感官评分均较高,可鲜食,也可加工成果汁;黄金毛桃的可滴定酸含量较高,口感偏酸,在加工过程中需要考虑降酸以保证产品口感;寒露蜜、红焗油、黄焗油、红芙蓉的VC含量较高,可加工成高VC含量的产品;黄金蜜三号、中蟠十七口感较为软糯,但可溶性固形物和可溶性糖含量较高,甜度高,适合鲜食,同时需要注意后期的运输贮藏环节。聚类分析结果将10个桃品种分为3个类群,可根据不同果实类群特性进行加工与贮藏。     

Lifetime of Event-driven Wireless Sensor Networks

研究了不同处理对磨盘柿贮藏过程中生理生化变化的影响.结果表明,0℃条件下真空包装冷藏能明显地延长磨盘柿保鲜期,在贮藏3个月后硬度仍能维持在1.97 kg,柿果实可溶性固形物、可溶性糖以及可溶性单宁变化与保鲜膜处理无明显差异,但类胡萝卜素含量却远远低于对照与常温条件下保鲜膜处理,此外,常温条件下縻盘柿果实贮藏不宜采用真空包装,保鲜膜包装并不能延长保鲜期,但能有效地抑制蒸腾失水,对于维持磨盘柿果实光洁、饱满的外观形态具有一定的辅助作用.     

Effect of Light Quality on Tomato Fruit Qualities in Turning-Color Period

就不同光质对番茄果实转色期品质变化的影响，以各色荧光灯为光源，在人工控光条件下进行了探究。结果表明，在转色期间不同处理番茄果实的可溶性糖和有机酸含量均于处理后8~10d达最高，而Vc和番茄红素于处理后12d达最大。但不同光质处理间差异明显，红光处理8d后果实可溶性糖含量达到最高，处理后8~10d Vc和番茄红素含量大幅度增加，成熟期比对照(白光)提前2d；红光和蓝光处理均提高了果实的可溶性糖及有机酸含量。各处理Vc含量以蓝光处理为最高，达123.7mg/kg(Fw)，显著高于对照。番茄红素含量以红光处理最高     

不同品种枸杞的低温贮藏品质差异性初步分析

为研究不同品种枸杞在低温贮藏环境中品质变化的差异性。以新疆精河县“0901”、“宁杞7号”、“圆果”3个品种枸杞（Lycium barbarum）为试材，置于3 ℃冷库中贮藏，定期测定果实呼吸强度、果形指数、色泽、可溶性固形物、抗坏血酸、可滴定酸、还原糖和可溶性糖含量。结果表明：低温贮藏过程中，3个品种枸杞均出现两个呼吸高峰；果形指数、可溶性固形物含量变化不大；可滴定酸、抗坏血酸、还原糖及可溶性糖含量呈动态变化。贮藏第24天与0 d相比，3个品种枸杞的还原糖和可溶性糖含量下降不明显。整个贮藏过程中，“圆果”枸杞的呼吸强度大体低于“宁杞7号”和“0901”枸杞，果形指数变化最小，色泽保持较好。因此，在3 ℃贮藏环境中，3个品种枸杞鲜果相比较而言，“圆果”枸杞的贮藏品质最好。     

Biological Activity and Quantification of Suspected Allelochemicals from Alfalfa Plant Parts

Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l^?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10^?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed.     

Changes in Seed Yield and Quality with Maturity in Onion (Allium cepa L., cv. 'Early Cream Gold')

Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality.     

Location of a high-lysine gene and the DDT-resistance gene on barley chromosome 7

Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.     

A note on the origin of Kalanchoë x vadensis Boom & Zeilinga (Crassulaceae)

Summary K x vadensis is a hybrid of K. blossfeldiana and K. marmorata obtained after doubling the number of chromosomes.     

Simultaneous Determination of Four Phenolic Acids in Radix Salviae Miltiorrhizae Formula Granules by QAMS

[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...     

Avoidance of leaf rust fungi in wild relatives of cultivated cereals

Summary Avoidance of rust fungi that was based on poor appressorium induction was previously found in Hordeum chilense. In the present study 95 accessions of Triticeae were screened for avoidance of Puccinia hordei. The percentage of appressorium formation per germinated spore ranged from 6 to 90%. On none of the 41 accessions of Aegilops, Agropyron, Elymus, Secale, Thinopyrum or Triticum studied was the rate of appressorium formation lower than 25%. Lower rates of appressorium formation were, however, found on accessions of wild barley species Hordeum brachyantherum, H. marinum, H. parodii and H. secalinum. Its implications in cereal breeding are discussed.     

Variation in forage grasses as hosts of the root-knot nematode Meloidogyne naasi (Franklin) and selection for resistance in ryegrass

Summary Reactions of 13 grasses to Meloidogyne naasi varied with species; ryegrasses, fescues and their hybrids were generally susceptible and cocksfoot and timothy resistant. Marked variation in host resistance levels occurred between genotypes within cultivars.Selection of single plants, followed by tests on replicate tillers, identified resistant and susceptible genotypes in both Italian and perennial ryegrass cultivars. Resistant plants had few nematode-induced galls and fewer females and eggs than susceptibles. There was more or less continuous variation, with many genotypes intermediate between extremes of resistance and susceptibility. Selected resistant and susceptible genotypes are of use in assessing variation in nematode populations and as controls for breeding and selection programmes.     

Current and future strategies in breeding lentil for resistance to biotic and abiotic stresses

Lentil production is limited by lack of moisture and unfavorable temperatures throughout its distribution. Waterlogging and salinity are only locally important. Progress has been made in breeding for tolerance to drought through selection for an appropriate phenology and increased water use efficiency and in breeding for winter hardiness through selection for cold tolerance.The diseases rust, vascular wilt, and Ascochyta blight, caused by Uromyces viciae-fabae, Fusarium oxysporum f. sp. lentis, and Ascochyta fabae f. sp. lentis, respectively, are the key fungal pathogens of lentil. Cultivars with resistance to rust and Ascochyta blight have been released in several countries and resistant sources to vascular wilt are being exploited. Sources of resistance to several other fungal and viral diseases of regional importance are known. In contrast, although the pea leaf weevil (Sitona spp.) and the parasitic weed broomrape (Orobanche spp.), and to a lesser extent the cyst nematode (Heterodera ciceri), are significant yield reducers of lentil, no sources of resistance to these biotic stresses have been found. Directions for future research in lentil on both biotic and abiotic stresses are discussed.     

Present status and future strategy in breeding faba beans (Vicia Faba L.) for resistance to biotic and abiotic stresses

Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.     

Water Extraction Process of Chinese Herbal Compound Man Gan Ning

[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...