复合涂膜液的筛选及其对鲜切苹果保鲜效果的影响

以不同浓度的壳聚糖、氯化钙、甘氨酸为复合涂膜液材料,以鲜切苹果的丙二醛含量为考察指标,采用正交试验方法筛选最优复合涂膜保鲜液,并以去离子水为对照,研究该复合涂膜保鲜液对贮藏在28、4℃条件下的鲜切苹果相关品质指标的影响。结果表明:1.0%壳聚糖、1.5%氯化钙和1.0%甘氨酸的复合涂膜液对鲜切苹果具有良好的保鲜效果,且在4℃时保鲜效果更佳。     

壳聚糖-明胶复合涂膜处理对南果梨保鲜效果的研究

采用壳聚糖、明胶、甘油制备不同配比的壳聚糖-明胶复合涂膜保鲜液,对南果梨进行涂膜处理,在室温下进行贮藏,通过对果实的失质量率、硬度、可溶性固形物和VC含量的测定,评价壳聚糖-明胶复合涂膜保鲜液对南果梨的保鲜效果。结果表明,壳聚糖-明胶复合涂膜液可以降低果实的失质量率,减缓硬度的下降速率,维持可溶性固形物和VC的含量,保鲜效果显著。保鲜效果最佳的涂膜保鲜液配比为壳聚糖0.9%,明胶1.25%,甘油0.4%。在此条件下,南国梨的保鲜期可延长至20 d左右。     

壳聚糖复合涂膜对杏鲍菇保鲜效果的研究

【研究目的】杏鲍菇在采后易失水褐化等原因降低食用及商品价值,为延长其货架期,需筛选出适于杏鲍菇的壳聚糖复合涂膜。【方法】该实验以杏鲍菇（Pleurotus eryngii）为研究材料,在室温（22±2℃）条件下,以去离子水浸涂杏鲍菇为对照,采用不同的壳聚糖复合涂膜处理进行保鲜实验,通过L9（33）正交试验筛选杏鲍菇保鲜的最佳复合涂膜配方,并研究其生理效应。【结果】结果表明,与对照相比,筛选出的最佳壳聚糖复合涂膜液能够有效降低杏鲍菇的褐变程度与含水率,延缓游离氨基酸含量、可溶性蛋白含量、可溶性总糖等各指标的变化幅度,保鲜效果达到显著水平（P＜0.05）。【结论】适于杏鲍菇的壳聚糖复合涂膜的配比为1.5%的壳聚糖+1.0%的乙酸+0.03%的吐温20+3.0%的甘油,该涂膜起到延缓杏鲍菇采后衰老,保持较好的营养价值和加工风味,达到保鲜目的。     

纳米材料用于鸡蛋涂膜的保鲜效果研究

研究纳米材料复合涂膜用于新鲜鸡蛋的保鲜效果。采用纳米SiO2溶液、壳聚糖溶液、纳米SiO2与壳聚糖的复合溶液对鸡蛋进行涂膜保鲜试验,在35 d的贮藏期间,对鸡蛋各项感官指标和内部品质指标变化进行分析。结果表明,当贮藏35 d时,3种处理对鸡蛋的保鲜效果均优于空白对照组。其中纳米SiO2与壳聚糖的复合涂膜效果次于壳聚糖涂膜效果,优于单独使用纳米SiO2涂膜和空白对照组。纳米SiO2涂膜贮藏至35 d时,感官表现为近似散黄但未散黄,质量损失率为4.98%,哈夫单位为58,蛋黄比率为24.3%,蛋黄系数0.25,蛋清pH值为9.2。纳米SiO2与壳聚糖复合溶液对新鲜鸡蛋具有较明显的保鲜作用。     

纳米材料用于鸡蛋涂膜的保鲜效果研究

研究纳米材料复合涂膜用于新鲜鸡蛋的保鲜效果。采用纳米SiO2溶液、壳聚糖溶液、纳米SiO2与壳聚糖的复合溶液对鸡蛋进行涂膜保鲜试验,在35 d的贮藏期间,对鸡蛋各项感官指标和内部品质指标变化进行分析。结果表明,当贮藏35 d时,3种处理对鸡蛋的保鲜效果均优于空白对照组。其中纳米SiO2与壳聚糖的复合涂膜效果次于壳聚糖涂膜效果,优于单独使用纳米SiO2涂膜和空白对照组。纳米SiO2涂膜贮藏至35 d时,感官表现为近似散黄但未散黄,质量损失率为4.98%,哈夫单位为58,蛋黄比率为24.3%,蛋黄系数0.25,蛋清pH值为9.2。纳米SiO2与壳聚糖复合溶液对新鲜鸡蛋具有较明显的保鲜作用。     

壳聚糖对葡萄涂膜保鲜的应用研究

以葡萄为保鲜对象,采用涂膜法研究壳聚糖复合溶液对葡萄的保鲜效果。通过比较流延膜的力学、阻隔和透明等性能以及对葡萄的保鲜效果,确定壳聚糖、醋酸、丙三醇、山梨酸钾的最佳添加量。结果表明,壳聚糖复合膜的保鲜效果主要受p H值和壳聚糖溶解性影响;由壳聚糖添加量1.5%,醋酸添加量1%,丙三醇添加量0.5%,山梨酸钾添加量0.5%组成的壳聚糖复合膜对葡萄的保鲜效果最佳,相对于空白组延长了保鲜期5 d。     

毛酸浆果涂膜保鲜技术的探讨

选用天然壳聚糖保鲜剂对毛酸浆果进行涂膜保鲜实验,探讨了不同条件下壳聚糖涂膜处理对毛酸浆果生理及贮藏效果的影响.并通过正交实验确定了最佳保鲜条件,涂膜保鲜剂浓度为15%,保鲜助剂为1%,温度为4℃.     

不同保鲜剂组合处理对草莓保鲜效果的影响

以全明星草莓为试验材料,研究CaCl2、植酸、柠檬酸和山梨酸钾不同浓度的复配组合及其结合壳聚糖涂膜处理对常温（20～25℃）条件下贮藏7d草莓果实品质的影响。结果表明,对在常温条件下草莓采后保鲜的最佳复配组合为：1％CaCl2＋0．15％植酸＋2％柠檬酸＋0．1％山梨酸钾。该复配保鲜剂再与l％壳聚糖制成涂膜,在抑制草莓果实腐烂,保持果实硬度,延缓可溶性固形物和VC含量下降方面的作用效果好于单纯复配保鲜剂。     

可食性液态膜复合保鲜剂对番茄保鲜效果的研究

以番茄为试材,通过壳聚糖、可溶性淀粉、羧甲基纤维素钠配制成不同浓度的复合保鲜液浸泡涂膜处理,研究其对番茄保鲜效果的影响。结果表明,复合保鲜液涂膜可有效地降低番茄果实的失重率、腐烂率、可溶性固形物含量,抑制多酚氧化酶活性,维持番茄VC含量,保持番茄果实较好的感官品质,且以0.5%壳聚糖+0.8%可溶性淀粉+0.3%羧甲基纤维素钠复配的复合保鲜液涂膜对番茄有较好的保鲜效果,15℃环境下其货架期延长到15 d以上。     

不同精油-羧甲基纤维素钠复合涂膜对草莓贮藏品质的影响

以新鲜草莓为试材,分别采用大蒜精油、山苍子精油、丁香花蕾精油、生姜精油复合羧甲基纤维素钠为涂膜保鲜原料,研究(15±2)℃条件下不同精油涂膜液处理对草莓贮藏品质的影响。结果表明,与对照组相比,山苍子精油、大蒜精油、生姜精油-羧甲基纤维素钠复合涂膜液均能显著降低草莓果实在贮藏过程中的腐烂指数及重量损失,显著抑制贮藏前期草莓果实的呼吸强度,进而抑制草莓果实在贮藏过程中可溶性固形物含量和花色苷含量的下降及丙二醛含量的上升,提高草莓的贮藏品质。其中,山苍子精油-羧甲基纤维素钠复合涂膜液对草莓的保鲜效果最佳,为草莓的贮藏保鲜提供了一种新的方法。     

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.     

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...     

Pollen and pollination experiments. III. The viability of apple and pear pollen as affected by irradiation and storage

Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed.     

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...     

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.     

Optimization of Extraction Technology and Determination of Content of Total Phenols of Leaves in Acanthopanax giraldii Harms

[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho...     

Cytoplasmic male sterility,resistance to gall mite and mildew,and season of leafing out in black currants

Summary Cytoplasmic male sterility (cms) is described in the F₁ hybrids Ribes × carrierei (R. glutinosum albidum × R. nigrum) and R. sanguineum × R. nigrum. In backcrosses to R. nigrum, progenies with R. glutinosum cytoplasm were either all male sterile, or segregated for full male fertility (F) and complete (S) and partial (I) male sterility. Ratios of F:I+S suggested that two linked genes controlled cms, F plants being dominant for one (Rf ₁) and recessive for the other (Rf ₂).Segregation for cms in relation to three linded genes, Ce (resistance to the gall mite, Cecidophyopsis ribes), Sph ₃(resistance to American gooseberry mildew, Sphaerotheca mors-uvae) and Lf ₁(one of two dominant additive genes controlling early season leafing out) indicated that Rf ₁and Rf ₂were in this linkage group. The gene order and approximate crossover values appeared to be: % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqef0uAJj3BZ9Mz0bYu% H52CGmvzYLMzaerbd9wDYLwzYbItLDharqqr1ngBPrgifHhDYfgasa% acOqpw0xe9v8qqaqFD0xXdHaVhbbf9v8qqaqFr0xc9pk0xbba9q8Wq% Ffea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dme% aabaqaciGacaGaamqadaabaeaafaaakeaacaWGdbGaamyzamaamaaa% baGaaiiiaiaacccacaGGWaGaaiOlaiaacgdacaGG0aGaaiiiaiaacc% caaaGaaiiiaiaacccacaGGGaGaamOuaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaaccdacaGGUaGaaiOmaiaacs% dacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaaaacaWGsbGaamOzaSGa% aGOmaOWaaWaaaeaacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccaaaGaamitaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccacaGGGaaaaiaadofacaWGWbGaamiAaSGa% aG4maaaa!6E4D!\[Ce\underline { 0.14 } Rf1\underline { 0.24 } Rf2\underline { } Lf1\underline { } Sph3\]. Crossover values of 0.36 for Ce-Lf ₁, and 0.15 for Lf ₁-Sph ₃were estimated from the relative mean differences in season of leafing out between seedlings dominant and recessive for Ce and Sph ₃.It is suggested that competitive disadvantage of lf ₁-carrying gametes and/or zygotes at low temperatures may be implicated in the almost invariable deficit of plants dominant for the closely linked mildew resistance allele Sph ₃. Poor performance of lf ₁- (and possibly lf ₂-) carrying gametes and young zygotes during periods of low temperature at flowering might also account for the liability of some late season cultivars and selections to premature fruit drop (running off).     

Screening techniques and sources of resistance to parasitic angiosperms

Parasitic angiosperms cause great losses in many important crops under different climatic conditions and soil types. The most widespread and important parasitic angiosperms belong to the genera Orobanche, Striga, and Cuscuta. The most important economical hosts belong to the Poaceae, Asteraceae, Solanaceae, Cucurbitaceae, and Fabaceae. Although some resistant cultivars have been identified in several crops, great gaps exist in our knowledge of the parasites and the genetic basis of the resistance, as well as the availability of in vitro screening techniques. Screening techniques are based on reactions of the host root or foliage. In vitro or greenhouse screening methods based on the reaction of root and/or foliar tissues are usually superior to field screenings and can be used with many species. To utilize them in plant breeding, it is necessary to demonstrate a strong correlation between in vitro and field data. The correlation should be calculated for every environment in which selection is practiced. Using biochemical analysis as a screening technique has had limited success. The reason seems to be the complex host-parasite interactions which lead to germination, rhizotropism, infection, and growth of the parasite. Germination results from chemicals produced by the host. Resistance is only available in a small group of crops. Resistance has been found in cultivated, primitive and wild forms, depending on the specific host-parasite system. An additional problem is the existence of pathotypes in the parasites. Inheritance of host resistance is usually polygenic and its transfer is slow and tedious. Molecular techniques have yet to be used to locate resistance to parasitic angiosperms. While intensifying the search for genes that control resistance to specific parasitic angiosperms, the best strategy to screen for resistance is to improve the already existing in vitro or greenhouse screening techniques.