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81.
Fusarium head blight (FHB) is a cereal disease of major importance responsible for yield losses and mycotoxin contaminations in grains. Here, we introduce a new measurement approach to quantify FHB severity on grains based on the evaluation of the whitened kernel surface (WKS) using digital image analysis. The applicability of WKS was assessed on two bread wheat and one triticale grain sample sets (265 samples). Pearson correlation coefficients between Fusarium‐damaged kernels (FDK) and WKS range from r = 0.77 to r = 0.81 and from r = 0.61 to r = 0.86 for the correlation between deoxynivalenol (DON) content and WKS. This new scoring method facilitates fast and reliable assessment of the resistance to kernel infection and shows significant correlation with mycotoxin content. WKS can be automated and does not suffer from the “human factor” inherent to visual scorings. As a low‐cost and fast approach, this method appears particularly attractive for breeding and genetic analysis of FHB resistance where typically large numbers of experimental lines need to be evaluated, and for which WKS is suggested as an alternative to visual FDK scorings.  相似文献   
82.
AIM:To investigate the effect of Kechuanning on airway remodeling and the protein level of p-ERK1/2 in lung tissues of asthmatic rats induced by virus. METHODS:The asthmatic rat model induced by respiratory syncytial virus was established. The experimental rats were divided into normal group, asthma model group, low dose (0.33 mL/kg), middle dose (3.0 mL/kg) and high dose (10 mL/kg) of Kechuanning groups, and PD98059 (3 mg/kg) group. The airway responsiveness of the rats was measured by animal ventilator. The pathological changes of the lung tissues were observed by HE staining. PAS staining and Masson staining were used to observe goblet epithelial cells metaplasia and airway collagen deposition. The expression of matrix metalloproteinases-9 (MMP-9) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) in the lung tissues of the rats was detected by immunohistochemical staining. The protein levels of ERK1/2 and p-ERK1/2 were determined by Western blot. RESULTS:Compared with model group, the airway responsiveness of the rats in middle dose and high dose of Kechuanning groups was significantly decreased (P<0.01), the injury of lung tissues was significantly decreased, the goblet epithelial cells metaplasia and airway collagen deposition were significantly reduced (P<0.01), and the expression of MMP-9 and TIMP-1 in the lung tissues was also significantly decreased (P<0.01). In addition, the protein level of p-ERK1/2 in high dose of Kechuanning group was significantly decreased compared with model group (P<0.01). CONCLUSION:Kechuanning may treat asthma by regulating the expression of p-ERK1/2 in the lung tissues and improving the airway remodeling symptoms of asthmatic rats induced by virus.  相似文献   
83.
张书芹  乐愉  武斐 《分子植物育种》2019,17(12):3817-3824
为了揭示陆地棉生长调控因子(growth-regulating factors, GRF)家族的功能,本研究利用全基因组信息在陆地棉基因组中鉴定了 33个GRF蛋白,并对这些家族成员进行了保守结构域分析、蛋白的基本理化性质分析、进化分析、基因的结构分析、染色体定位、保守基序分析和组织表达模式分析。研究表明,陆地棉GRF均含有QLQ和WRC 2个保守结构域,系统进化分为4个亚家族,基因定位在19条染色体上,基因上有2~19个蛋白编码区域,大多数的基因在柱头、子房和20 d的种子中高量表达。本研究弄清了棉花GRF家族的基本信息,为进一步研究棉花GRF家族成员的功能提供了理论指导。  相似文献   
84.
‘粉荷’星花玉兰,成蕾早,花蕾产量高。花期2月中旬至3月下旬,花瓣形如荷花,色泽艳丽,花量大,抗性强,病害少,易管理,观赏价值高。  相似文献   
85.

Context

Context Bats are considered as an ecological indicator of habitat quality due to their sensitivity to human-induced ecosystem changes. Hence, we will focus the study on two indicator species of bats as a proxy to evaluate structure and composition of the landscape to analyze anthropic pressures driving changes in patterns.

Objectives

This study develops a spatially-explicit model to highlight key habitat nodes and corridors which are integral for maintaining functional landscape connectivity for bat movement. We focus on a complex mountain landscape and two bat species: greater (Rhinolophus ferrumequinum) and lesser (Rhinolophus hipposideros) horseshoe bats which are known to be sensitive to landscape composition and configuration.

Methods

Species distribution models are used to delineate high-quality foraging habitat for each species using opportunistic ultrasonic bat data. We then performed connectivity analysis combining (modelled) suitable foraging habitat and (known) roost sites. We use graph-theory and the deviation in the probability of connectivity to quantify resilience of the landscape connectivity to perturbations.

Results

Both species were confined to lowlands (<1000 m elevation) and avoided areas with high road densities. Greater horseshoe bats were more generalist than lesser horseshoe bats which tended to be associated with broadleaved and mixed forests.

Conclusions

The spatially-explicit models obtained were proven crucial for prioritizing foraging habitats, roost sites and key corridors for conservation. Hence, our results are being used by key stakeholders to help integrate conservation measures into forest management and conservation planning at the regional level. The approach used can be integrated into conservation initiatives elsewhere.
  相似文献   
86.
在充分考虑机械臂伺服电机智能速度检测装置的结构和闭环运动过程控制的基础上,将智能交流接触器引入到了采摘机器人机械臂关节伺服电机的反馈控制中,并建立了PID闭环反馈调节回路,有效地提高了机械臂的控制精度。同时,将智能交流接触器以速度控制函数的形式嵌入到了PID控制环节,采用ADMAS和MatLab软件对机械臂的轨迹控制精度进行了测试,并利用Mat Lab软件计算得到了关节的控制变量,以Spline形式将变量导入到了ADMAS中对机械臂两关节进行控制。通过仿真得到了机械臂关节的输入和输出位移随时间变化曲线和机械臂末端的运动结果,结果表明:输入和输出的位移基本吻合,并且机械臂末端可以按照预定的圆环轨迹运动,从而验证了智能交流接触器PID控制的控制精度。  相似文献   
87.
为掌握汉中市小麦条锈病流行规律,提高病害测报的科学性和准确性,采用DPS数据处理系统,对多年来汉中市小麦条锈病测报资料进行了主导因素分析,筛选出影响发病程度的主要因子包括小麦感病品种种植比例(x1)、秋苗病田率(x2)、秋苗单位面积平均病叶数(x3)、1月份平均气温(x6)、上年11月份降雨量(x11)、早春病田率(x18)、3月中旬病田率(x19),与发生程度(y)进行逐步回归分析,建立了发病程度预测模型:y=-6.354 7+0.084 0x1+0.022 8x3+0.662 8x6+0.020 9x11,R2=0.968 7。拟合预测符合率为92.31%,相对误差8.96%。利用预测模型对2014-2016年汉中市小麦条锈病进行预测,预测的病级分别为2.93、3.21、1.92,与2014、2015、2016年发生的实际病级3、3、2相吻合。此模型可应用于生产中小麦条锈病的测报。  相似文献   
88.
Flavan-3-ol monomers and polymers composition of seeds from wild (17) and autochthonous (8) Vitis vinifera grapes growing in northern Tunisia were evaluated. Wild grape seeds were spherical with a small beak and relatively a high seed/berry ratio (~ 18.1%w/w). Local cultivars developed pyriform-shaped seeds with a well-developed beak representing on average 2.2% of total weight of the berry. Flavanol concentrations ranged between 40.9 and 67.5 mg/g FW in seeds from wild accessions and between 48.9 and 96.7 mg/g FW in seeds from cultivated grapes. Differences between accessions were highly significant (p < 0.01) and seeds from cultivar ‘Boukhasla’ showed the highest polyphenols content. Among flavan-3-ol monomers, (+)-catechin was predominant for all ecotypes and generally their abundance was: (+)-catechin (Cat) > (?)-epicatechin (Ec) > (?)-epicatechin-3-O-gallate (EcG). The Cat/Ec ratio was approximately 1.7 for wild grapes while it was about 2.5 for cultivated grapes. Procyanidins in wild seeds differed from cultivated ones by a lower mDP and higher proportions of galloylated derivatives, likely to affect fruit bitterness and astringency. (?)-epicatechin was the main extension subunit in grape seed procyanidins, reaching on average 52% in wild and 58% in cultivated seeds. Hierarchical cluster analysis based on seeds morphometry and procyanidin profile indicated close proximity between some wild and cultivated grapes suggesting that some cultivars derived from ancestral events of local domestication or cross hybridization with native wild plants.  相似文献   
89.
基于随机森林算法和气象因子的砀山酥梨始花期预报   总被引:5,自引:4,他引:1  
准确预报始花期是制定砀山酥梨花期管理措施和赏花活动方案的重要基础。该文利用1983-2018年砀山酥梨始花期的定位观测物候数据和平行观测的气象资料,采用线性趋势法,揭示始花期演变趋势;采用相关分析,筛选影响始花期的关键气象因子,依据不同预报日期构成特征变量集;采用随机森林算法(Random Forest, RF),自3月11日开始预报到3月25日终止预报,每日训练1个预报模型。结果表明,1)1983-2018年始花期呈极显著提早发生趋势,每10a约提前2.750 d(P<0.001)。2)16个逐日气象预报模型中,共计有200个气象因子与始花期早迟密切相关,相关系数在0.469~0.789之间;各气象预报模型的训练集与测试集的平均正确率(Nd)分别为92.9%和75.5%、平均均方根误差(RMSE)分别为1.693~2.870和2.240~7.237、平均决定系数(R2)分别为0.891和0.701。3)2019年试验预报中,提前15日准确预报出当年始花期。该文研究表明RF在梨树始花期逐日气象预报中有一定业务应用潜力,预报准确率基本满足气象服务需求。  相似文献   
90.
Deoxynivalenol(DON)is considered to be the most harmful mycotoxin that affects the intestinal health of animals and humans.Phenethyl isothiocyanate(PEITC)in feedstuff is an anti-nutritional factor and impairs nutrient digestion and absorption in the animal intestinal.In the current study,we aimed to explore the effects of PEITC on DON-induced apoptosis,intestinal tight junction disorder,and its potential molecular mechanism in the porcine jejunum epithelial cell line(IPEC-J2).Our results indicated that PEITC treatment markedly alleviated DON-induced cytotoxicity,decreasing the apoptotic cell percentage and pro-apoptotic mRNA/protein levels,and increasing zonula occludens-1(ZO-1),occludin and claudin-1 mRNA/protein expression.Meanwhile,PEITC treatment ameliorated DON-induced an increase of the inducible nitric oxide synthase(iNOS)and cyclooxygenase 2(COX-2)mRNA levels and intracellular reactive oxygen species(ROS)level,and a decrease of glutathione peroxidase 1(GPx1),superoxide dismutase 2(SOD2),catalase(CAT)and heme oxygenase 1(HO-1)mRNA levels.Additionally,PEITC treatment significantly down-regulated autophagy-related protein 5(ATG5),beclin-1 and microtubuleassociated protein 1 light chain 3B(LC3-II)mRNA/protein levels,decreased the number of green fluorescent protein-microtubule-associated protein 1 light-chain 3(GFP-LC3)puncta and phosphatidylinositol 3 kinase(PI3K)protein expression,and up-regulated phospho-protein kinase B(p-Akt)and phospho-mammalian target of rapamycin(p-mTOR)protein expression against DON.However,the activation of autophagy by rapamycin,an autophagy agonist,abolished the protective effects of PEITC against DON-induced cytotoxicity,apoptosis and intestinal tight junction disorder.Collectively,PEITC could confer protection against DON-induced porcine intestinal epithelial cell injury by suppressing ROSmediated autophagy.  相似文献   
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