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1.
The effect of heat stress on the components of grain weight was analysed in wheat ( Triticum aestivum L.) varieties differing in grain weight stability. The wheat varieties PBW154, Sonalika and Hindi62 were raised in the field (New Delhi, India; 77°12' E, 28°40' N, 228.6 m a.s.l.) at three dates of sowing: 19 November 1992 (DOS I), 14 December 1992 (DOS II) and 18 January 1993 (DOS III). The late-sown crop (DOS III) experienced 6–8 °C warmer temperatures during grain development than the crop sown at the normal time (DOS I). The heat susceptibility index (S) revealed that grain weight was less susceptible to heat in Sonalika and PBW154 than in Hindi62. Heat stress reduced both the grain growth duration (GGD) and the grain growth rate (GGR). The grain weight reduction in PBW154 and Sonalika was mainly due to a reduction in GGR, while that of Hindi62 was due to a reduction in GGD. In vivo studies on starch and protein synthesis in excised endosperm at 15, 25 and 35 °C revealed that both processes were more thermotolerant in Hindi62 than in PBW154. The grain starch content was stable in Hindi62 while that in PBW154 was significantly reduced under heat stress. The grain nitrogen content at maturity increased in both varieties under heat stress. It was concluded that the heat susceptibility of grain weight in Hindi62 was mainly due to a reduction in GGD, although GGR, starch and protein synthesis were more thermotolerant in developing grains of Hindi62 than in those of PBW154.  相似文献   
2.
Provision of feed supplies for the rapidly growing livestock population is essential in West Asia. Shortages can be alleviated by growing forage crops in the existing fallow lands.
Narbon vetch (Vicia narbonensis L.) is a leguminous species with high yield potential, drought tolerance and cold resistance. It could be used for grain and straw production as source for animal feed in dry areas. It is good source of protein with seeds contain 28 % protein yielding 364 kg per hectare protein, whilst straw contains 9 % protein and yields a similar amounts of digestible protein per hectare.
Nine promising lines of Narbon vetch developed at ICARDA were tested at two sites over four years under rainfed conditions. Since climatic conditions were considered to be of considerable importance, each site in each year was treated as a separate environment to give eight environments with annual rainfall varied from 195 to 504 mm.
Narbon vetch possessed high seedling vigour with rapid winter growth and negligible cold damage. Grain yield varied form 0.47 to 1.90 t/ha, with a harvest index varying from 30 to 40 %. The data indicated that below 300 mm rainfall the grain yield varied from 0.47 t/ha when rain fall was 195 mm to 1.4 t/ha when rainfall was 245 mm. Most of the lines had wide adaptation to dry areas in terms of both grain yield and stability. Climate, except early spring rains had little effect on biological and grain yields.  相似文献   
3.
ABSTRACT: To clarify the quantitative changes in the transport of orally intubated protein into the blood circulation as macromolecules in development, immunoglobulin Y (IgY) extracted from chicken eggs was administered orally to juvenile Japanese eel, Anguilla japonica . For the first experiment, which was performed before the commencement of artificial feeding, the oral delivery of 2.0 μg/0.1 g bodyweight of IgY resulted in a rapid increase in plasma IgY to a maximum of 2.30 μg/mL. However, the transport of IgY into the blood decreased significantly in the experiments that followed, which were performed after 12, 25 and 42 days. During this period, bodyweight increased approximately by a factor of eight, and rapid growth of the stomach was observed histologically. Possible contributions for the development of the alimentary canal to the diminishment of intestinal protein assimilation are discussed.  相似文献   
4.
In this study, the effects of nitrogen (N) rate (60, 120, 180 and 240 kg N ha?1 applied in three equal dressings at seeding and after the first and second cuttings) and stubble height (7, 14 and 21 cm) on the dry matter (DM) yield, crude protein (CP) content, and CP yield of a sorghum–sudangrass hybrid [Sorghum bicolor (L.) Moench × Sorghum sudanense (Piper) Stapf., cv. Pioneer 988] in the three‐cut system was investigated. The N rate had no significant effect in the first and third cuttings, but in the second cutting DM yields increased significantly with increase in N rate. The highest yield of 9.1 t ha?1 was obtained with 80 kg N ha?1 for the average of 2 years at the second cutting, but no significant difference was found among the 40, 60 and 80 kg N ha?1 rates. CP content and yield were not significantly affected by N rate at the first and third cuttings, but CP content and yield were significantly affected by application of N at the second cutting. Stubble height had a significant effect on CP content at the third cutting. However, it had no significant effect on CP content at the first and second cuttings. Stubble height had a significant effect on the CP yield at the first cutting, but no significant effect on CP yield at the second and third cuttings.  相似文献   
5.
根据中国药典对注射剂的要求,对花粉多糖的蛋白质、鞣质、树脂、草酸盐、炽灼残渣、钾离子、砷盐、重金属含量进行测定,均符合规定,达到质量标准。  相似文献   
6.
张玲  王志跃 《中国家禽》2004,26(23):17-19
研究选择21周龄新扬州鸡种公鸡135只,随机分成9组。采用两因子析因设计,分别设粗蛋白质水平为17%、14%和11%,钙水平为3.3%、2.3%和1.3%,构成9种日粮处理。比较在繁殖期全程饲喂不同粗蛋白质和钙水平日粮对种公鸡新城疫水平的影响,结果表明:日粮粗蛋白质水平对免疫后15、30天公鸡体内的抗体水平有显著影响(P<0.05),对免疫90天的水平有极显著影响(P<0.01);日粮钙对免疫后30天的抗体水平有极显著的影响(P<0.01);二者的交互作用对它影响不显著(P>0.05);低蛋白低钙组抗体水平显著高于高蛋白高钙组(P<0.05)。  相似文献   
7.
LIU Ping-ping  ZHANG Yuan 《园艺学报》2004,20(11):2053-2057
AIM: To investigate the effects of β-mercaptoethanol (β-ME) and all-trans rentinal acid (RA) on glial fibrillary acidic protein (GFAP) expression in mesenchymal cells derived from mouse fetal liver in vitro. METHODS: Cells suspension from 14.5-days-old mouse fetal liver were cultured in DMEM/HEPES/F12 supplemented with 20% FCS and mesenchymal cells were acquired after discarding nonadherent cells. The 5th passage cells were induced by β-ME and RA. The characteristics of treated cells were assayed by immunocytochemistry staining at 5 hours and 5 days after induction. β-actin as an internal control, GFAP gene expression of mesenchyal cells was detected with semi-quantitative RT-PCR. RESULTS: After being inducted by β-ME and RA, 80% approximately of the cells exhibited typical neural morphology and about 85% expressed GFAP phenotype. Semi-quantitative RT-PCR showed that mRNA expression of GFAP increased in treated cells versus untreated cells (P<0.01). CONCLUSION: GFAP expression in mesenchymal cells derived from mouse fetal liver in vitro increases after being treated with β-ME and RA.  相似文献   
8.
跨膜蛋白是一类位于细胞膜上的重要蛋白质,对于维持细胞稳态和调节细胞的生长发育具有关键作用,因此一直受到广泛研究。本文将介绍一种重要的跨膜蛋白——体积调节阴离子通道(Volume Regulated Anion Channel, VRAC),并全面综述其分子结构特征和多个生理功能,旨在为后续研究工作提供参考。  相似文献   
9.
小球藻(Chlorella)是一种单细胞真核藻类,属绿藻门、绿藻纲、绿球藻目、小球藻科、小球藻属[1].作为最早开发的真核微藻之一,具有高营养价值、生长快速、结构简单、易工业化集成等显著优点.其细胞形态为球形或椭圆形,直径 3~12μm,呈单生或聚集成群状生长[2],分布广泛,多见于淡水、咸水和土壤中.作为地球上最早的...  相似文献   
10.
分别用虾蛄蛋白浆替代饲料中2%和4%的鱼粉,并以乌贼膏为对照,研究其对河蟹摄食和生长的影响。结果表明,饲料中添加虾蛄蛋白浆对河蟹的诱食作用与乌贼膏相当,但摄食量显著高于乌贼膏组。此外,虾蛄蛋白浆还具有明显的促进河蟹脱壳生长的作用,其作用机制可能与其中氨基酸、小肽、胆固醇等含量丰富有关。  相似文献   
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