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441.
Field experiment was conducted to investigate the impact of phosphorus (P) and beneficial microorganism (BM) on the yield and yield components wheat (Triticum aestivum L., cv. Siren-2010). The experiment was conducted under full (five irrigations) and limited (two) irrigation conditions at the Research Farm of The University of Agriculture Peshawar during winter 2012–13. The experiment under both full and limited irrigated conditions was laid out in randomized complete block design using three replications. The results showed that irrigated plots produced more spikes m?2 (254), grains spike?1 (55.5), heavier thousand grains weight (39.4 g), and higher grain yield (3612 kg ha?1 than limited irrigated condition. Application of P at the highest rate (90 kg P ha?1) produced more spikes m?2 (260) and grains spike?1 (52.4), and increased maximum thousand grain weight (39.1 g) and grain yield (3617 kg ha?1). Application of BM at the highest rate (30 L ha?1) resulted in maximum number of spikes m?2 (257) and grains spike?1(51.7), highest thousand grains weight (39.1 g) and grain yield (3765 kg ha?1). The results confirmed that under full irrigated condition the increase in both P and BM levels (90 kg P ha?1 and 30 L ha?1, respectively) and under limited irrigated condition the intermediate levels of both P and BM (60 kg P ha?1 and 20 L ha?1, respectively) could increase wheat productivity under semi-arid conditions.  相似文献   
442.
Development of crop cultivars with high yield under low nitrogen (N) supply is a basic approach for the enhancement of agricultural sustainability. The previous studies showed that Tibetan wild barley shows wider genetic diversity in abiotic stress and poor fertility tolerance. In this study, four barley genotypes (two Tibetan wild and two cultivated), differing in N use efficiency (NUE), were characterized for their growth and physiological responses to low N stress. The genotypes ZD9 (cultivated) and XZ149 (wild) with high NUE performed better in terms of shoot dry weight (DW) and photosynthetic parameters under both low and normal N levels and had higher antioxidative enzyme activities, N concentration, and accumulation in both shoots and roots under low N stress. The current results showed the substantial difference among barley genotypes in low N tolerance and verified the significance of Tibetan wild barley in the genetic improvement of cultivated barley in NUE.  相似文献   
443.
Ten mungbean (Vigna radiata R. Wilczek) genotypes were evaluated for grain yield and phosphorus (P) efficiency at adequate and deficient P in soil. Genotypes differed significantly in plant height, grain yield, P accumulation (PA), and other P-efficiency parameters at both P levels. The genotype “AEM-40/30” had maximum plant height, grain yield, and phosphorus physiological efficiency index (PPEI) under P deficiency. The genotypes were distributed into nine groups based on their relationship between total PA and grain yield at deficient P level. Moreover, genotypes were categorized into low, medium, or high efficient for each parameter by allotting index score (1, 2, or 3). Maximum cumulative index score (25) was attained by the genotypes “AEM-40/30 and AEM-20/3/87”, and genotype “AEM-30/5/8/90” scored least total index (14). The significant differences among mungbean genotypes for PA, phosphorus harvest index (PHI), PPEI, and grain yield can be exploited to select or identify P-efficient mungbean genotypes.  相似文献   
444.
<正>近年来,作为脂肪成分之一的磷脂是鱼类营养研究十分活跃的领域。由于磷脂营养具有明确的营养价值,因此已经广泛的用于饲料生产。但是对于不同的鱼类以及鱼类发育的不同阶段,磷脂应用的原理和方法仍是近年来相关人士普遍关心的问题。  相似文献   
445.
The current study aimed to evaluate the efficacy of selenium nanoparticles (SeNPs), combined or loaded with chitosan (COS), in broiler chickens reared under standard management protocols. The parameters under investigation were production performance, organ development, components of the intestinal barrier, and ileal microbial count. Two hundred and forty day-old chicks were raised in five groups, with each group containing eight replicates (n=6/replicate). The control group received a basal diet whereas the other four groups received basal diets supplemented with SeNPs (0.5 mg/kg), COS (200 mg/kg), SeNPs+COS (0.5 mg/kg SeNPs + 200 mg/kg COS), and SeNPs-loaded COS (SeNPs-L-COS) (200 mg/kg) respectively. On day 35, two birds/replicate were sampled to collect the viscera under investigation. The results revealed that dietary inclusion of SeNPs-L-COS increased (p<0.05) the body weight gain and improved (p<0.05) feed conversion ratio. Similarly, SeNPs-L-COS supplementation increased (p<0.05) the small intestinal villus surface area as well as the count of acidic goblet cells and intraepithelial lymphocytes when compared with the control group. Whereas the total goblet cell count was higher (p<0.05) in the small intestines of both the SeNPs+COS and SeNPs-L-COS groups. Microbial analysis of ileal contents also revealed an increase (p<0.05) in Lactobacilli species count with a concurrent decrease (p<0.05) in Escherichia coli count in the SeNPs-L-COS group when compared with the COS and control groups. Based on the results of the current trial, we can conclude that supplementation with SeNPs-L-COS is a superior combination for promoting the gut health and performance of broilers.  相似文献   
446.
目的 分析无叶假木贼叶绿体基因组结构特征,阐明假木贼属在藜科中的分类地位,进一步探究其密码子偏好性和确定最优密码子。 方法 基于CTAB法从无叶假木贼幼嫩同化枝中提取总DNA;通过Illumina Genome Analyzer HiSeq 2000高通量测序平台进行测序;使用GetOrganelle和Plann对叶绿体基因组序列进行组装和注释;利用MISA对叶绿体基因组中简单重复序列(SSR)进行分析;使用MAFFT v. 7. 450和IQ-TREE v. 2. 1. 1软件进行多序列比对、构建最大似然法(Maximum likelihood,ML)系统进化树;使用DnaSP 6. 0软件计算核苷酸多态性值;通过CUSP和Codon W 1. 4. 2软件进行密码子偏好性研究。 结果 无叶假木贼叶绿体基因组全长为154 084 bp,包括1个大单拷贝区(LSC,85 124 bp)、1个小单拷贝区(SSC,18 934 bp)、1对反向重复序列(IRa和IRb,25 013 bp)。共注释到132个基因,包含83个蛋白编码基因,8个rRNA基因,37个tRNA基因和4个假基因。SSR位于基因间区的数量最多(70.4%),单碱基(A/T)重复类型SSR数量最多。系统发育树的最优构树模型为TVM + F + R3,藜科划分为4个聚类组,其中,无叶假木贼与梭梭属和猪毛菜属亲缘关系最近。trnS-trnG(exon1)、ndhF-rpl32、rpl32-trnL、rps16(exon1)-trnQ和ycf1是高核苷酸多态性区域。共确定20个最优密码子(UUU、UAU、UGU、CAU、UCU、UCA、UUA、CUU、CCU、AGA、GAA、ACU、ACA、AAU、GAU、AAA、GUU、GCU、GGU、CAA),均以A/U结尾,密码子使用偏好性主要受自然选择影响,突变等影响因素对其影响较弱。 结论 无叶假木贼叶绿体基因组结构保守,呈典型的四分体结构。在藜科的系统发育中,无叶假木贼与梭梭属和猪毛菜属亲缘关系最近。鉴定的高变区和SSR位点可用于藜科属间物种的分子鉴定。无叶假木贼叶绿体基因组密码子偏好以A/U结尾,确定的20个最优密码子有助于其外源密码子的优化。研究结果可为无叶假木贼分子标记开发、系统进化及叶绿体基因工程研究提供参考。  相似文献   
447.
BackgroundStroke is caused by disruption of blood supply and results in permanent disabilities as well as death. Chlorogenic acid is a phenolic compound found in various fruits and coffee and exerts antioxidant, anti-inflammatory, and anti-apoptotic effects.ObjectivesThe purpose of this study was to investigate whether chlorogenic acid regulates the PI3K-Akt-Bad signaling pathway in middle cerebral artery occlusion (MCAO)-induced damage.MethodsChlorogenic acid (30 mg/kg) or vehicle was administered peritoneally to adult male rats 2 h after MCAO surgery, and animals were sacrificed 24 h after MCAO surgery. Neurobehavioral tests were performed, and brain tissues were isolated. The cerebral cortex was collected for Western blot and immunoprecipitation analyses.ResultsMCAO damage caused severe neurobehavioral disorders and chlorogenic acid improved the neurological disorders. Chlorogenic acid alleviated the MCAO-induced histopathological changes and decreased the number of terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells. Furthermore, MCAO-induced damage reduced the expression of phospho-PDK1, phospho-Akt, and phospho-Bad, which was alleviated with administration of chlorogenic acid. The interaction between phospho-Bad and 14-3-3 levels was reduced in MCAO animals, which was attenuated by chlorogenic acid treatment. In addition, chlorogenic acid alleviated the increase of cytochrome c and caspase-3 expression caused by MCAO damage.ConclusionsThe results of the present study showed that chlorogenic acid activates phospho-Akt and phospho-Bad and promotes the interaction between phospho-Bad and 14-3-3 during MCAO damage. In conclusion, chlorogenic acid exerts neuroprotective effects by activating the Akt-Bad signaling pathway and maintaining the interaction between phospho-Bad and 14-3-3 in ischemic stroke model.  相似文献   
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