1- MCP对冬枣常温贮藏生理和品质的影响

以白熟期冬枣为试材,经不同浓度1-MCP（250,500,1000nL/L）处理后,在常温条件下贮藏30天时,1-MCP处理能够显著抑制冬枣乙醇积累,保持较好的硬度、可溶性固形物和VC含量,降低腐烂指数和乙烯释放速率,提高贮藏后期呼吸速率,但对失水率和转红指数的影响不显著。不同浓度1-MCP处理以1000nL/L保鲜效果最佳。     

1-MCP对冬枣常温贮藏生理和品质的影响

以白熟期冬枣为试材,经不同浓度1-MCP（250,500,1000nL/L）处理后,在常温条件下贮藏30天时,1-MCP处理能够显著抑制冬枣乙醇积累,保持较好的硬度、可溶性固形物和VC含量,降低腐烂指数和乙烯释放速率,提高贮藏后期呼吸速率,但对失水率和转红指数的影响不显著。不同浓度1-MCP处理以1000nL/L保鲜效果最佳。     

1-MCP处理对常温贮藏金红苹果生理及品质的影响

以金红苹果为试材,在常温(20±1)℃条件下贮藏,研究不同浓度1-MCP(0.5、1.0、1.5μL/L)熏蒸处理对金红苹果生理及品质的影响。结果表明,在贮藏期内,与对照组(未熏蒸处理)相比,经1-MCP处理后,果实的乙烯释放速率和呼吸强度均明显降低,并推迟了乙烯高峰的出现,增强了过氧化物酶(POD)活性,延缓了衰老;降低了多酚氧化酶(PPO)活性,抑制了果肉褐变;保持了果肉较高的硬度,减缓了可滴定酸(TA)含量和可溶性固形物(TSS)含量的下降。在不同浓度的1-MCP处理中,以1.0μL/L1-MCP处理的果实贮藏效果最好,具有较高的好果率,肉质坚硬,果实酸甜适口,果皮色泽红青鲜艳。     

1-MCP和外源乙烯处理对番木瓜果实贮藏品质的影响

研究了1-MCP与乙烯利处理对番木瓜果实贮藏品质和成熟衰老的影响.结果表明:乙烯利处理、乙烯利处理后立即用1-MCP处理、乙烯利处理24 h后再用1-MCP处理,均能明显加速果实的软化进程和色泽变化.降低果品品质,缩短贮藏时间;而单独用1-MCP处理则能显著抑制果实的转黄和发病.保持果实中的TA和VC含量,显著延长果实...     

1-MCP对鸭梨贮藏期间生理品质变化的影响

以鸭梨为试材,经1-MCP处理后冷藏,研究不同采收期鸭梨在冷藏期间的生理与贮藏品质的变化。试验结果表明,1-MCP对果实的呼吸强度和乙烯释放量具有显著的抑制作用,对早采果实抑制呼吸作用效果最为显著;在冷藏期间具有乙烯释放高峰,不同采收期的果实均于贮藏180天时达到峰值。1-MCP对减缓果实可溶性固形物含量的消耗,以及对早采和稍晚采果实抑制硬度效果明显,也对适时采收和稍晚采收果实果皮相对电导率变化的作用效果较好。     

不同处理对“新疆早黄”无花果采后生理的影响

以"新疆早黄"无花果为试材,在温度0~2℃,相对湿度(RH)80%~85%的环境下分别采用不同浓度1-MCP(0.5、1.0μL/L)或Cl O2(5、10μL/L)熏蒸处理12 h,并在相应环境下贮藏,研究不同浓度1-MCP或Cl O2处理对无花果采后生理的影响。结果表明:与对照组相比,1-MCP或Cl O2处理均能够推迟无花果呼吸高峰和乙烯释放高峰的出现时间,降低呼吸高峰和乙烯释放高峰,保持较好的超氧化物歧化酶(SOD)、过氧化物酶(POD)及过氧化氢酶(CAT)活性,抑制丙二醛(MDA)的累积,其中1.0μL/L1-MCP处理组效果最好。     

南瓜籽油溶剂法提取工艺及脂肪酸成分的研究

以鸭梨为试材,经1-MCP处理后冷藏,研究不同采收期鸭梨在冷藏期间的生理与贮藏品质的变化.试验结果表明,1-MCP对果实的呼吸强度和乙烯释放量具有显著的抑制作用,对早采果实抑制呼吸作用效果最为显著;在冷藏期间具有乙烯释放高峰,不同采收期的果实均于贮藏180天时达到峰值.1-MCP对减缓果实可溶性固形物含量的消耗,以及对早采和稍晚采果实抑制硬度效果明显,也对适时采收和稍晚采收果实果皮相对电导率变化的作用效果较好.     

不同贮藏温度下1-MCP处理对凯特杏采后色泽及品质的影响

采用浓度为1.0μL·L-1的1-甲基环丙烯（1-MCP）处理凯特杏果实16 h后,将其分别于（20±0.5）℃和（8±0.5）℃条件下贮藏15 d,研究1-MCP处理对杏果实采后生理、品质及色泽的影响。结果表明,在两种贮藏温度下,与对照相比,1-MCP处理可显著抑制凯特杏果实的呼吸强度及乙烯释放量,有效延迟果实软化和可滴定酸含量的下降,提高果面色泽亮度,抑制果实转黄,提高好果率,8℃贮藏条件下果实的可溶性固形物含量显著高于对照。经1-MCP处理后,（20±0.5）℃下凯特杏果实具有商品性的时间可达7~10 d,（8±0.5）℃下凯特杏果实具有商品性的时间可达15 d。     

1-MCP处理对珊夏苹果贮藏品质的影响

以珊夏苹果果实为试材,研究了500nL·L^-1、1000nL·L^-1和1500nL·L^-1浓度的1-MCP处理对果实冷藏期间硬度等贮藏品质的影响,并对果实冷藏100天后货架期期间的硬度、可溶性固形物含量、可滴定酸含量和果肉白度进行了分析。试验结果表明,3个浓度的1-MCP处理均可明显地降低果实在冷藏期间呼吸强度与乙烯释放速率,对于延缓珊夏果实冷藏期间和冷藏100天后货架期间的果肉硬度、可滴定酸含量和果肉白度的下降有明显的效果;在3个处理浓度中,500nL·L^-1与1500nL·L^-1浓度处理效果优于1000nL·L^-1的1-MCP处理效果。     

UV-C结合1-MCP处理对香梨采后果实品质及生理活性的影响

以库尔勒香梨(Pyresbretschnei deri Rehd)为试材,研究UV-C结合1-MCP处理对香梨采后品质及生理变化的影响,为香梨采后保鲜及病害控制提供理论依据。香梨采后用UV-C结合1-MCP处理,贮藏于低温(-1℃,RH：90%~95%)条件下,研究其对果实品质和生理活性的影响。结果表明：UV-C结合1- MCP处理能够显著抑制果实硬度的下降,保持较高的可溶性固性物含量,抑制VC含量和色度角的降低。经UV-C结合1-MCP处理的香梨呼吸跃变延后,呼吸高峰降低,乙烯释放量下降,乙烯释放高峰推迟。此外,UV-C结合1-MCP处理降低了细胞膜渗透率的上升,抑制了丙二醛(MDA)含量的增加。由此表明：UV-C结合1-MCP处理能够延缓香梨采后果实的生理衰老,保持果实品质。     

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.     

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.     

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...     

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.     

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.