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81.
不同立地条件下哈密大枣果园营养特征及果实品质的研究   总被引:1,自引:0,他引:1  
[目的]研究不同土壤类型(沙土、沙壤土和粘土)下,不同树龄(初果期和盛果期)哈密大枣在花芽分化期、开花盛期和果实膨大期的土壤和叶片,主要营养成分及其果实品质之间的差异性.[方法]以哈密大枣作为试材,主要测定土壤有机质、碱解氮、速效磷和速效钾含量,叶片的氮、磷、钾含量,以及果实VC、可滴定酸、可溶性糖和可溶性固形物含量.[结果]不同土壤类型不同树龄下哈密大枣果园在各物候期内0~20 cm 土层的有机质、碱解氮、速效钾和速效磷含量均明显高于20~80 cm土层;初果期三种土壤类型的哈密大枣果园在0~20 cm土层中开花盛期的有机质、碱解氮、速效磷和速效钾含量比花芽分化期和果实膨大期较高.不同树龄不同土壤类型哈密大枣果园在不同物候期间相比,除了初果期粘土枣园开花盛期的叶片氮和钾含量均高于花芽分化期和果实膨大期以外,叶片氮和钾含量在果实膨大期均最高,而叶片磷含量在花芽分化期均最高.初果期哈密大枣果实品质在土壤类型之间比较而言,沙壤土枣园的果实VC、可滴定酸和可溶性糖含量最高,而粘土枣园的果实可溶性固形物含量较高;盛果期而言,沙土枣园的果实VC和可滴定酸含量最高,沙壤土的可溶性糖和固形物含量最高.[结论]在哈密大枣生产中,根据土壤营养情况花芽分化期要适当加大磷肥的施用比例,而果实膨大期要增加氮肥和钾肥的施用量.  相似文献   
82.
ABSTRACT

This study describes the potential use of olive oil-lemon juice emulsions containing different levels of lemon juice (0, 25, 35, and 50% v/v) as a flavoring, preservative, and antioxidant agent in marinated anchovy. The phenolic content and antioxidant activity of lemon juice, olive oil, and olive oil-lemon juice sauces as well as chemical, oxidative, and sensorial changes of marinade samples were analyzed. Increasing the level of lemon juice in sauces retarded the chemical and oxidative changes of marinated anchovy. However, increasing the level of lemon juice more than 35% in sauces led to a decrease in sensorial acceptability. Chemical and oxidative qualities of all the sauced samples were in the limit of deterioration during 100 days of storage. Although marinated anchovy samples treated with sauce containing 50% lemon juice had a significant inhibitor effect on chemical and oxidative deterioration, samples treated with sauce containing 35% lemon juice received the highest overall acceptability score.  相似文献   
83.
一串红原产于南美洲热带地区,性喜温不耐寒,喜光但也能耐半荫,既适于露地花坛栽植,又适于盆栽观赏,适栽温度18-25℃,生长适温20-25℃,高于30℃时花、叶变小,植株生长发育受阻,落花落叶现象非常严重。库尔勒地区,4月下旬一串红移栽花坛。初栽时,留基部4-6叶片进行摘心,促使其多萌发分枝。在栽培管理正常的情况下,摘心后约经过30d可2次抽穗开花,故在调节花期时,要注意控制最后一次摘心的时间。  相似文献   
84.
本文采用野外实地调查、标本整理及资料查阅的方法,研究塔克拉玛干沙漠西南部荒漠环境的短命植物,分析其种类组成、生活型特征(物候特性)和植物区系类型。结果:①研究区的短命植物种类有十字花科、禾本科、菊科、紫草科、茄科、车前科、罂粟科及牻牛儿苗科等8科21属的27种,其中十字花科有15种。新记录种有卷果涩荠、大蒜芥、蝎尾菊、偏穗雀麦、旱麦草、中亚天仙子、牻牛儿苗、垂果大蒜芥及砂蓝刺头等10种,占该区域短命植物的37%。②该区域短命植物生活史特征有夏性、冬性及春性。③该区域短命植物分别属于北温带分布、地中海-西亚至中亚分布、旧世界温带分布、世界分布及中亚分布,其中北温带分布及地中海-西亚至中亚分布的植物有15种,占研究区统计种类的51. 86%。该研究结果丰富了新疆南部特殊生境下的短命植物类群,为开发和保护该地区植物种质资源及揭示短命植物对不同生态环境的响应具有重要意义。  相似文献   
85.
[目的]研究新疆野生沙枣仁中脂肪和蛋白质组分。[方法]采用气质联用法测定新疆野生沙枣仁油脂中脂肪酸的含量及组分;采用分级提取法分离沙枣仁中的蛋白质,并用半微量定氮法对蛋白质中的氨基酸组分进行分析。[结果]新疆野生沙枣仁的含油率为8.2%.以不饱和脂肪酸为主要成分,其中以亚油酸含量最高,为46.52%,其次为油酸,亚麻酸和硬脂酸。沙枣仁中粗蛋白平均含量为11.31%。其中以球蛋白和清蛋白为主,占蛋白质总量的70%以上,而残渣蛋白、醇溶蛋白、谷蛋白含量比较低。沙枣仁蛋白质中含有18种氨基酸,其中天冬氨酸含量最高,为12.7%,其次为谷氨酸,占11.8%,酪氨酸为9.33%,亮氨酸为8.11%,赖氨酸为7.22%,精氨酸、丝氨酸、丙氨酸、缬氨酸含量次之,组氮酸、蛋氨酸和胱氨酸含量最少。其中人体必需氨基酸含量达28.76%。[结论]新疆野生沙枣仁营养丰富,具有广阔的应用前景。  相似文献   
86.
A sustainable semi-intensive pond aquaculture technology including major carp species as cash-crop and small indigenous fish species (SIS) as food for the farmers' families is being optimized in Bangladesh. The inclusion of silver carp (Hypophthalmichthys molitrix), a cheap large species affordable by poor farmers, is now being considered. As part of a study on the effects of this filter feeder on polycultures including the large carps rohu (Labeo rohita), catla (Catla catla) and common carp (Cyprinus carpio) and the SIS punti (Puntius sophore) and mola (Amblypharyngodon mola), an experiment was carried out to test the effects of silver carp and of each SIS species on the growth, survival and yield of the large and small fish and on pond ecology.The ecology of the ponds was dominated by changes in time, strongly related to the development of a surface plankton scum at the beginning of the culture season and weather conditions. The surface scum increased decomposition processes and decreased algal development in the water body, promoted photosynthesis and ammonium release and reduced nitrification. Over those effects, the presence of silver carp in the ponds decreased algal biomass through grazing and promoted nitrification providing and resuspending particles in the water column. These effects were also produced by mola, but were evident only in the absence of silver carp. Punti stirring on the pond bottom increased nutrient flow from the sediments into the water column and promoted nitrification, but were also evident only in the absence of silver carp.The addition of 10 silver carp over the 99 large carps stocked in the 100 m2 fishponds did not affect punti and mola reproduction in the ponds, negatively affected rohu and catla growth and yield by about 20-25% but not their survival, did not affect common carp performance, reduced punti harvested biomass by 10%, reduced mola performance by about 50%, and silver carp's own biomass increased total yield and total income in about 20% each. The addition of 250 mola or punti to the large carp polycultures did not affect the performance of any of the large carps. The decreased income from selling the more expensive large carps was more than compensated by that obtained from silver carp, which increased total income by 13-24% as compared to the corresponding treatments without silver carp. This allows the option to the farmer of selling part of the silver carp to complete the cash income that would have been obtained from large carps only if silver carp would not be stocked, and consume the rest with the family.  相似文献   
87.
The present study was conducted to investigate the effect of silymarin on experimental liver toxication induced by Fumonisin B1 (FB1) in BALB/c mice. The mice were divided into six groups (n = 15). Group 1 served as the control. Group 2 was the silymarin control (100 mg/kg by gavage). Groups 3 and 4 were treated with FB1 (Group 3, 1.5 mg/kg FB1, intraperitoneally; and Group 4, 4.5 mg/kg FB1). Group 5 received FB1 (1.5 mg/kg) and silymarin (100 mg/kg), and Group 6 was given a higher dose of FB1 (4.5 mg/kg FB1) with silymarin (100 mg/kg). Silymarin treatment significantly decreased (p < 0.0001) the apoptotic rate. FB1 administration significantly increased (p < 0.0001) proliferating cell nuclear antigen and Ki-67 expression. Furthermore, FB1 elevated the levels of caspase-8 and tumor necrosis factor-alpha mediators while silymarin significantly reduced (p < 0.0001) the expression of these factors. Vascular endothelial growth factor (VEGF) and fibroblast growth factor-2 (FGF-2) expressions were significantly elevated in Group 4 (p < 0.0001). Silymarin administration alleviated increased VEGF and FGF-2 expression levels (p < 0.0001). In conclusion, silymarin ameliorated toxic liver damage caused by FB1 in BALB/c mice.  相似文献   
88.
Background: Sheep is important in the socio-economic lives of people around the world. It is estimated that more than half of our once common livestock breeds are now endangered. Since genetic characterization of Nigerian sheep is still lacking, we analyzed ten morphological traits on 402 animals and 15 microsatellite DNA markers in 384 animals of the 4 Nigerian sheep breeds to better understand genetic diversity for breeding management and germplasm conservation. Results: Morphological traits of Uda and Balami were significantly (P < 0.05) higher than Yankasa, which were both higher than West African Dwarf (WAD) sheep. Stepwise discriminant analysis showed tail length, rump height, chest girth, ear length and chest depth as the most discriminating variables for classification. Mahalanobis distances show the least differentiation between Uda and Balami and the largest between WAD and Balami sheep. While 93.3% of WAD sheep were correctly assigned to their source genetic group, 63.9% of Yankasa, 61.2% of Balami and 45.2% of Uda were classified correctly by nearest neighbour discriminant analysis. The overall high Polymorphism Information Content (PIC) of all microsatellite markers ranged from 0.751 to 0.927 supporting their use in genetic characterization. Expected heterozygosity was high for all loci (0.783 to 0.93). Mean heterozygote deficiency across all populations (0.171 to 0.534) possibly indicate significant inbreeding (P < 0.05). Mean values for FST , FIT and FIS statistics across all loci were 0.088, 0.394 and 0.336 respectively. Yankasa and Balami are the most closely related breeds (DA = 0.184) while WAD and Balami are the farthest apart breeds (DA = 0.665), which is coincident with distance based on morphological analysis and population structure assessed by STRUCTURE. Conclusions: These results suggest that within-breed genetic variation in Nigerian sheep is higher than between-breeds and may be a valuable tool for genetic improvement and conservation. The higher genetic variability in Yankasa suggests the presence of unique ancestral alleles reflecting the presence of certain functional genes which may result in better adaptability in more agro-ecological zones of Nigeria. These genetic characteristics are potentially useful in planning improvement and conservation strategies in Nigerian indigenous sheep.  相似文献   
89.
The aim of this study was to understand the off-axis tensile properties of the developed two dimensional multistitched multilayer E-glass/polyester woven nano composites. It was found that the specific off-axis tensile strength of unstitched structure was higher than that of the machine stitched structure due to stitching caused filament breakages. But it was slightly lower than that of the machine stitched/nano structure. In addition, the specific off-axis tensile strength of machine stitched/nano composite structure was slightly higher than that of the machine stitched structure. When the nano silica material in the unstitched E-glass/polyester composite structure increased, the off-axis specific tensile strength and the modulus of the unstitched/nano structures increased whereas, the off-axis specific tensile strain of the unstitched/nano structures decreased. The damaged areas of the unstitched/nano structures increased, when the nano silica material in the unstitched E-glass/polyester woven composite structures increased. The failures under the off-axis tensile load of the stitched or stitched/nano structures were confined at narrow area due to the multistitching. On the other hand, it was observed that the off-axis failure of unstitched/nano or stitched/nano woven E-glass/polyester composite structures showed more brittle behavior.  相似文献   
90.
Summary Thirteen cultivars were tested for presence ofPhoma exigua var.foveata in stems and green leaves. The frequency of segments yielding the pathogen increased with time during the growing season and varied between cultivars from 13 to 36% and their distribution pattern was irregular. There were significant differences between cultivars to this symptomless invasion of the green shoots. The value of such cultivar differences depends on the interpretation of the importance of stem inoculum in carrying the disease to the next tuber generation.
Zusammenfassung Es wurden 13 Kartoffelsorten auf das Vorhandensein vonPhoma exigua var.foveata in Stengeln und grünen Bl?ttern untersucht. Pflanzknollen, die nach künstlicher Infektion faulten, wurden im Feld ausgepflanzt; nach 5, 12 und 17 Wochen wurden pro Sorte vier Stengel mit Bl?ttern nach dem Zufallsprinzip ausgew?hlt, wobei jeder Stengel eine Pflanze repr?sentierte. Die Stengel wurden gewaschen, getrocknet und in 5 cm-Segmente geteilt. Nach Oberfl?chensterilisation wurden die Segmente und die Blattschnitte in Petrischalen auf ein selektives Agarmedium gebracht, das zur F?rderung der Pyknidienentwicklung Paraquat enthielt.P. exigua var.foveata wurde auf Malzextraktagar bestimmt, der Thiophanatmethyl und Chloramphenicol enthielt. Die Sorten reagierten unterschiedlich auf die Infektion, wie an der Anzahl der Schnitte, die das Pathogen lieferten, zu ersehen ist. Die Nachweish?ufigkeit war am niedrigsten bei der ersten und am h?chsten bei der letzten Probenahme (Tab. 2). Die mittleren Prozentwerte varierten von 13% bis 36%, die Reihenfolge war zwischen den Jahren ?hnlich (Tab. 1). Das Verteilungsmuster der Schnitte, die das Pathogen lieferten, war unregelm?ssig; es wurde überall in Stengelschnitten und Bl?ttchen vom oberirdischen Trieb nachgewiesen und in nur wenigen F?llen auch in Stengelsegmenten unterhalb der Bodenoberfl?che (Tab. 3). Die Werte zeigen, dass die Anf?lligkeit der Sorten zur symptomlosen Invasion der grünen Triebe differiert. Inwieweit in dieser Phase des Lebenszyklus des Pilzes eine Resistenzauslese lohnend ist, h?ngt von der m?glichen Bedeutung des Stengelinokulums als Quelle für die Infektion der Knollennachkommenschaft ab. Es war mit dieser Untersuchung nicht beabsichtigt, Fragen, die sich auf die Ausbreitung des Pilzes beziehen, zu beantworten; ein besseres Verst?ndnis der Biologie dieses Krankheitserregers ist aber entscheidend zur rationalen Anwendung der Ergebnisse in der Pflanzenzüchtung.

Résumé La présence dePhoma exigua var.foveata dans les tiges et les feuilles vertes est étudiée sur treize variétés de pommes de terre. Des tubercules de semence pourris après contamination artificielle, sont plantés au champ. Après 5, 12 et 17 semaines, 4 tiges avec les feuilles de chaque variété sont prélevées au hasard, chaque tige représentant une plante. Les tiges sont lavées, séchées et coupées en segments de 5 cm. Après une stérilisation de surface les segments et des sections de folioles sont placés en boites de pétri sur un milieu sélectif à base d'agar contenant du paraquat afin de favoriser le développement des pycnides.Phoma exigua var.foveata est identifié sur malt agar contenant du thiophanate-méthyl et chloramphenicol. Les variétés répondent différemment à l'infection, comme le montre le nombre de sections hébergeant le pathogène. La fréquence de détection est la plus faible à la première date d'échantillonnage et la plus élevée à la dernière (tableau 2). Le pourcentage moyen varie entre 13 et 36%, le classement est similaire entre les années (tableau 1). La distribution du pathogène hébergé par les échantillons est irrégulière. Il est détecté sur des sections de tiges et des folioles au dessus du sol et dans quelques cas sur des segments de tiges en dessous de la surface du sol (tableau 3). Les données montrent que la sensibilité des variétés à l'infection des parties aériennes est variable. L'intérêt d'une sélection à la résistance pour cette phase du cycle du champignon dépend de l'importance potentielle de l'inoculum sur tige en temps que source de contamination des tubercules-fils. Cette étude n'a pas pour but d'expliquer la dissémination du champignon, mais une meilleure connaissance de la biologie du pathogène est fondamentale pour une application rationnelle des résultats de la multiplication variétale.
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