Versatile physiological functions of the Nudix hydrolase family in berry development and stress response in grapevine

Nudix hydrolases are widely distributed across all classes of organisms and provide the potential capacity to hydrolyze a wide range of organic pyrophosphates. Although Nudix hydrolases are involved in plant detoxification processes in response to abiotic and biotic stresses, the biological functions of Nudix hydrolases remain largely unclear in grapevine.In the present study, a total of 25 putative grapevine Nudix hydrolases(VvNUDXs) were identified by bioinformatics analysis and classified int...     

香蕉MaSULTR3家族成员的全基因组鉴定与不同温度下表达模式分析

利用生物信息学分析法对香蕉MaSULTR3基因家族成员进行全基因组鉴定、蛋白特性分析、分子进化树分析、启动子顺式作用元件分析以及低温胁迫下叶片转录组的FPKM值分析;其后,利用基因组数据结合RT-PCR方法克隆了'天宝蕉'(Musa spp.,AAA Group)组培苗MaSULTR3.1-2基因的ORF序列;最后,利...     

Curcumin attenuates rat lung ischemia/reperfusion injury by interfering with autophagy

AIM To investigate the role of curcumin （CUR） in lung ischemia/reperfusion （I/R） injury （LIRI） and its relationship with autophagy. METHODS 40 SD rats were randomly divided into sham operation （sham） group, I/R group, solvent （DMSO） group, CUR group and CUR+rapamycin （CUR-Rap） group. The rats were intraperitoneally injected with normal saline, DMSO, CUR or CUR+Rap before operation. After the rat LIRI model was established, the lung tissues were taken to measure W/D, TLW, IAR, and the contents of SOD and MDA were also measured to indicate the oxidative stress level. Light and electron microscopes were used to observed the morphology and ultrastrucure of lung tissues. The expression levels of autophagy-related proteins were determined by Western blot to evaluate autophagy levels. RESULTS Compared with sham group, wet weight/dry weight （W/D）, total lung water （TLW）, injured alveoli rate（IAR） and malondialdehyde （MDA） content in all other groups were increased, superoxide dismutase （SOD） activity was decreased, the levels of autophagy were increased （P<0.05）, and lung tissue injury and cell ultrastructural damage were aggravated in CUR group. Compared with DMSO group, W/D, TLW and IAR and MDA content were decreased, SOD activity was decreased, autophagy levels were also decreased （P<0.05）, and lung tissue and cell ultrastructural damage were attenuated. Compared with CUR group, W/D, TLW, IAR and MDA content were increased, SOD activity declined, the autophagy levels were increased （P<0.05）, and damage of lung tissues and cells were more serious in CUR-Rap group. CONCLUSION Curcumin attenuates the lung I/R injury in rats, and its mechanism may be related to the reduction of oxidative stress and the inhibition of autophagy.     

自由基清除剂对香蕉水分胁迫的保护作用

本文用苯皿酸钠、ａ－生育酚和Ｖ 作为外源自由基清除剂,研究其对香蕉的抗旱保护作用结果表明,外源自由基清除剂预处理降低了干旱条件下香蕉叶片细胞的膜生和膜脂过氧化程度,延缓叶绿素、可溶性蛋白南含量的降低,表现出外源自由基保护剂对减轻干旱引起的自由基伤害,提高香蕉抗旱能力具保护作用。不同清除剂的保护效果存在差异,以ａ－生育酚效果最好。     

低磷胁迫下玉米幼苗生理响应及相关基因表达研究

以玉米品种合344为试验材料,对低磷胁迫下玉米幼苗叶片生理表型指标与玉米叶片转录组差异基因表达数据联合分析,探究低磷胁迫下与玉米幼苗叶片生理表型变化相关的关键响应基因及其调控规律.结果表明,低磷胁迫下玉米叶片的叶绿素荧光参数(FV/FM)以及叶绿素含量均有不同程度的降低,并且叶绿素合成相关基因大部分为下调表达,叶绿素降...     

苹果跌落冲击力学特性研究

果品跌落冲击力学特性的研究是表征其流变性能、跌落损伤机理以及设计作业件的基础。构建果实自由跌落冲击力学参数测试系统,对“富士”苹果进行不同高度的单次自由跌落、同一部位的多次跌落试验。在测试获得冲击力－时间数据的基础上,基于运动学原理进行理论分析计算,得到加速度－时间、冲击力－变形量、应力－应变以及跌落冲击弹性恢复系数等动态关系。研究结果表明随着跌落高度、跌落次数的增加,苹果冲击力、加速度峰值、冲击最大变形、冲击结束后的残余变形逐渐增大。苹果跌落弹性恢复系数随着跌落高度而逐渐降低,随着跌落次数增加而逐渐增大。跌落次数对跌落变形量增加的影响不显著,随着跌落次数的增加残余变形变化很小。     

薄壁封闭环磨削回弹的建模与数值研究

提出了卡环制造过程中磨削回弹的计算模型。根据卡环的精度和啮合力要求,设计了特殊制造工艺。考虑弯曲残余应力,对磨削工序进行力学分析,提出了磨削回弹弯矩、磨削回弹后搭叠长度和啮合力变化的计算模型;开发了卡环制造辅助工艺系统——Shuttle,对卡环磨削工序进行了模拟,并结合实验讨论了磨削前后曲率半径、啮合力和搭叠长度随余量的变化规律。研究表明：随着磨削余量的增加,试样磨削前的啮合力增加,而磨削回弹后的啮合力呈下降趋势;试样磨削前后的搭叠长度均呈下降趋势,并且试样截面惯性矩越大,磨削回弹后试样的搭叠长度下降速度越慢;在各工序阶段,试样的曲率半径有不同程度的增加。     

生物炭对盐碱条件下海滨锦葵根系与土壤特性的影响

为探索生物炭对盐碱条件下植物根系与土壤特性的影响,以海滨锦葵为材料,在盐碱土壤中添加不同含量的生物炭,测定植株根系活力、根系生长、土壤pH值、土壤电导率、土壤容重、土壤孔隙度等指标。结果显示:在盐碱胁迫下,添加生物炭提高了海滨锦葵根系活力,中高浓度生物炭明显促进植株根系生长,土壤pH值与电导率均降低,土壤容重呈上升趋势,而土壤孔隙度呈现下降趋势。经比较,5.0%和7.5%生物炭对盐碱条件下海滨锦葵根系发育与土壤特性的调控效果相对较好。     

灌浆初期高温胁迫对水稻籽粒活性氧积累及产量形成的影响

【目的】研究灌浆初期高温胁迫对水稻籽粒活性氧积累及产量形成的影响,为耐热水稻种质资源的筛选和鉴定提供理论依据。【方法】以长江中下游地区普遍推广种植的8个水稻品种为材料,在灌浆初期进行高温胁迫（38 ℃/32 ℃,昼/夜）,研究各水稻品种在灌浆初期高温胁迫下的ROS含量、抗氧化酶活性、淀粉合成相关酶活性、产量及其构成要素以及稻米品质的差异。【结果】与对照相比,灌浆初期高温胁迫导致水稻籽粒O^-₂·和H₂O₂含量及抗氧化酶活性显著增加。在不同水稻品种中,淀粉合成相关酶活性对灌浆初期高温胁迫的响应具有差异性。高温胁迫下,产量损失较大水稻品种的O^-₂·和H₂O₂含量增幅较大,淀粉合成酶活性受高温胁迫影响也较大。灌浆初期高温胁迫导致水稻结实率、千粒质量、收获指数和产量显著下降,其中黄华占和湘两优900的产量损失较小,在灌浆初期的耐热性较强;粤王丝苗、泰优390和湘两优2号的产量损失较大,在灌浆初期的耐热性弱。灌浆初期高温胁迫导致糙米率、精米率和淀粉含量显著下降,垩白粒率和垩白度增加。高温胁迫下,产量损失较大水稻品种的淀粉含量下降幅度较大,稻米品质受高温胁迫影响也较大。在高温胁迫下,水稻产量与ROS含量显著负相关,而与抗氧化酶活性显著正相关。产量、籽粒加工指标、淀粉含量和淀粉合成酶活性的抗逆系数与ROS含量的抗逆系数显著负相关,而与抗氧化酶活性的抗逆系数显著正相关。【结论】灌浆初期高温胁迫导致水稻籽粒ROS过量积累是降低淀粉合成酶活性和淀粉含量,进而导致产量和稻米外观加工品质下降的重要因素。ROS的增加量可作为灌浆初期水稻耐热性评价的参考指标。     

人工老化和低温胁迫对陆地棉种子活力的影响和评价

[目的]研究人工老化处理和低温胁迫对陆地棉种子萌发的影响,为陆地棉种子耐低温和耐贮藏性研究提供支持和种质资源.[方法]以12份陆地棉种子为材料,通过标准发芽条件、低温胁迫发芽和人工老化处理后发芽,统计并分析发芽势、发芽率、发芽指数、活力指数、苗长、根长、苗鲜重和根鲜重等8个指标.[结果]各逆境对种子活力不同指标影响不同...