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1.
Seed longevity is a very important characteristic controlling seed quality. However, the mechanism underlying this characteristic is poorly understood. In this study, 'FH7185', a storable rice variety, the germination rate of which was 66.63%, much higher than the control after artificial ageing under relative humidity 88% and 42°C for 21 days. Different methods were applied to reveal the involvement of proteins during ageing of rice seeds. In total, 35 differential proteins were identified from 2D‐PAGE, and 3,719 proteins from iTRAQ analysis. A comparison of these two methods showed that not all protein types could be detected on the 2D‐PAGE gels, and the dynamic range was somewhat limited. So the comprehensive proteome map from the iTRAQ analysis was used to identify the quantitatively regulated proteins that played roles in seed longevity, and found that the most marked change was the increased abundance of many metabolic enzymes, especially the ones involved in α‐linolenic acid metabolism in the embryos during ageing. OsLOX2 and OsLOX3 had a negative effect on seed longevity, which were lower in FH7185 than the control. The dehydrogenase (LOC_Os07g44430) which played a major catalytic role in lipid peroxidation, also changed significantly during ageing. Therefore, OsLOX2, OsLOX3 and Loc_OS 07G44430 may be involved in the regulation of seed longevity with a synergistic effect.  相似文献   
2.
为探讨低温驯化对南方小花蝽雌成虫冷藏的影响,在室内15℃下饲养7 d作为低温驯化处理,研究了驯化后与未驯化的南方小花蝽雌成虫分别在4、6和10℃下冷藏其寿命、存活率和致死中时间(LT50)的异同。结果表明,无论是否进行低温驯化,南方小花蝽雌成虫的寿命都显著大于对照(25℃下饲养)。在10℃冷藏条件下,是否经过低温驯化对南方小花蝽雌成虫寿命没有明显影响,但在4℃和6℃条件下,低温驯化能明显延长雌成虫的寿命,分别延长了80.7%和83.7%。南方小花蝽雌成虫存活率均随冷藏时间的延长而下降,在同一低温冷藏温度下经低温驯化处理的南方小花蝽存活率比未驯化的高。经低温驯化的南方小花蝽雌成虫在4、6和10℃冷藏时,其LT50分别比未经驯化的延长了30.0%、57.8%和40.4%。以上结果表明南方小花蝽的寿命具有可塑性,低温驯化有利于南方小花蝽的冷藏,6℃可作为南方小花蝽长期储藏的温度。  相似文献   
3.
试验通过收集出生、产犊和离群的记录,探究宁夏地区荷斯坦牛成母牛的淘汰情况,分析影响该地区奶牛长寿性的因素。对15 523头荷斯坦牛的生产寿命、在群寿命和利用胎次进行描述性统计,分析淘汰时的胎次、季节和泌乳阶段的分布情况;计算生产寿命、在群寿命和利用胎次之间的表型相关,利用固定模型分析场-出生年、出生季节、牧场规模、淘汰原因和头胎产犊月龄对长寿性的影响。结果显示,宁夏地区荷斯坦牛的平均利用胎次为2.36胎,平均生产寿命为736.59 d。荷斯坦牛成母牛在产后第1个月内的淘汰风险最高,随着泌乳阶段的延长,成母牛在每个胎次内的淘汰风险均逐渐降低;随着淘汰胎次的增加,奶牛淘汰更加集中发生在产后泌乳早期;生产寿命、在群寿命和利用胎次之间存在较高的表型相关(均>0.9),场-出生年、出生季节、牧场规模、淘汰原因和头胎产犊月龄对长寿性有显著影响(P<0.05),春季出生和22月龄头胎产犊的奶牛长寿性表现更好。本研究初步揭示了宁夏地区荷斯坦牛成母牛的淘汰规律和长寿性的影响因素,为宁夏地区牛群选育成母牛长寿性状奠定了基础。  相似文献   
4.
The recent success obtained in term of increasing the litter size of sows has not correlated with a reduction of replacement rate. There is thus an increased economic demand for gilts with optimal reproductive potential and longevity. Unfortunately, replacement gilts are known to be more susceptible to diseases and less productive than multiparous sows. Interestingly, reproductive performance, resistance to diseases and longevity could all be largely affected by oxidative stress. To investigate whether oxidative stress conditions could account for the poor longevity of gilts, three distinct groups of conventional Yorkshire × Landrace sows were formed based on their similar age and parity (gilts, second parity sows as well as fourth to fifth parity sows). All animals were slaughtered during the post‐ovulatory period, and blood as well as tissue samples were collected. Biomarkers of oxidative damage to proteins (carbonyls) and DNA (8‐OHdG) were analysed in samples. Specific mRNA expression of major antioxidants such as glutathione peroxidases 1, 3 and 4 (GPx1, GPx3, GPx4) as well as superoxide dismutases 1 and 2 (Sod1, Sod2) were monitored in liver and kidney samples by quantitative RT‐PCR. Specific enzymatic activities of both GPx and SOD were measured by spectrophotometric assays. The plasma concentration of protein carbonyls was significantly different between the three groups with the highest concentration being observed in gilts (p ≤ 0.001). The mRNA expression levels of GPx1 and GPx4 were also significantly increased in the liver of gilts when compared to multiparous sows (p ≤ 0.05). SOD2 enzymatic activity was found to be higher in the liver of gilts than multiparous sows (p ≤ 0.05). Taken together, these results indicate that replacement gilts sustain significantly higher oxidative conditions than multiparous sows. Current findings may contribute to the design of nutritional regimens that will increase the productivity of gilts by counteracting oxidative stress.  相似文献   
5.
蠋蝽Arma chinensis Fallou是一种优良的捕食性天敌昆虫, 在多种农林害虫的生物防治中发挥着重要作用?为明确不同地理来源的蠋蝽种群的生物学特征, 指导蠋蝽的扩繁及在不同地区的释放应用, 本研究测定并比较了河北廊坊和贵州六盘水两个地区蠋蝽种群的表观形态?发育历期?成虫寿命和繁殖能力等生物学指标?结果表明, 贵州六盘水蠋蝽种群的体型显著大于河北廊坊种群; 河北廊坊蠋蝽种群的若虫期虽长于贵州六盘水种群, 但二者无显著差异; 河北廊坊种群配对饲养的雄虫和单雌饲养的雌虫其寿命显著长于贵州六盘水种群, 配对饲养的雌虫寿命两种群间无显著差异; 两个种群蠋蝽雌虫均在羽化后5~8 d进入产卵高峰期, 贵州六盘水种群的产卵前期较短, 且配对饲养条件下其单雌产卵量显著高于河北廊坊种群?  相似文献   
6.
明确温度与米蛾成虫生殖和卵发育的关系并进行模式化表达,为人工智能规模化繁育米蛾及利用其卵进行天敌昆虫的繁殖提供科学依据。在室内5个恒温条件下(15℃、20℃、25℃、30℃、35℃)测定米蛾卵的发育历期、孵化进度、孵化率及成虫产卵量、产卵动态、寿命等。结果显示,米蛾卵在15℃条件下停滞发育(不能孵化),在20~35℃的温度范围内,卵的发育历期与温度呈负相关,卵的发育速率总体趋势符合Logistic曲线模型V=0.25/[1+exp(5.06-0.24t)](R=0.9993,F=358.06,P=0.0373),孵化率与温度的关系符合二项式关系模型y=1/[0.0144+526644.37exp(-t)](R=0.9471,F=26.14,P=0.0145),在试验温度范围内,米蛾成虫单雌产卵量有随着温度升高呈现先增加后降低的趋势,且米蛾单雌产卵量(y)与温度(t)的关系符合二项式模型y=-2.38t2+128.42t-1383.58(R=0.9941,F=84.28,P=0.0117),成虫寿命亦随着温度的升高逐渐缩短。米蛾雌虫产卵适宜温度范围是25~30℃,最适温度为26.98℃,卵发育的适宜温度范围是20~30℃,最适温度为26.90℃。  相似文献   
7.
黄皮种子脱水敏感性与核酸、蛋白质代谢的关系   总被引:3,自引:0,他引:3  
黄皮种子发育晚期,胚内核酸和蛋白质合成能力增强,而花生种子发育晚期则呈下降趋势。脱水处理使生理成熟期黄皮胚核酸和蛋白质合成能力急剧下降,核酸水解酶活性增强。生物大分子代谢能力的变化是黄皮种子脱水敏感性的分子基础。  相似文献   
8.
Impact of dominance effects on sow longevity   总被引:1,自引:0,他引:1  
The purpose of the current study was to estimate variance components, especially dominance genetic variation, for overall leg action, length of productive life and sow stayability until third and fifth parity in the Finnish pig populations. The variance components were estimated in two purebred [Landrace (LR), n = 23 602 and Large White (LW), n =22 984] and crossbred (LR × LW, n = 17 440) data sets. Five different analyses were carried out for all the traits to compare the effect of sows’ inbreeding, common litter environment and parental dominance in the statistical model when determining the genetic correlations of the traits for the two purebred and crossbred populations. Estimated heritabilities for the traits ranged from 0.04 to 0.06. The estimates for the proportion of dominance variance of phenotypic variance (d2) varied between 0.01 and 0.17, and was highest in the crossbred dataset. The genetic correlations of the same traits in purebred and crossbred were all high (>0.75). Based on current results, the effect of dominance should be accounted for in the breeding value estimation of sow longevity, especially when data from crossbred animals are included in the analyses. Because dominance genetic variation for sow longevity exists that variation should be utilized through planned matings in producing sows for commercial production.  相似文献   
9.
P K JENSEN 《Weed Research》2009,49(6):592-601
Persistence of seeds of the four winter annual grass species, Alopecurus myosuroides , Bromus sterilis , Bromus hordeaceus and Vulpia myuros , were studied under field conditions. The studies also included the two dicotyledon species, Tripleurospermum inodorum and Galium aparine . Seed samples were stored in the field at different depths in the plough layer for a year. Following germination, seedling emergence was taken as an indicator of field persistence. In a supplementary investigation, seed samples were placed on the soil surface or buried at 2 cm for a month and then tested for viability. Persistence of the two Bromus species was very short, irrespective of depth and duration of burial. Persistence of the other species was positively correlated with incorporation of seeds to a few centimetres depth. Increasing the depth of incorporation below 2 cm had a variable influence on persistence. Persistence of seeds placed directly on the soil surface was short, whether they were left there for a year or a month. Whether seeds at the soil surface were left uncovered or covered with chopped straw had limited influence on seed persistence. However, straw cover significantly increased persistence of A. myosuroides seeds and there was the same tendency with T. inodorum .  相似文献   
10.
A Review of Fine Root Dynamics in Populus Plantations   总被引:1,自引:0,他引:1  
Production of native and hybridized varieties of Populus has received considerable interest in temperate regions as an alternative to agricultural crops and an additional wood source, while acting as a potential carbon (C) sink to offset emissions of fossil fuel-based greenhouse gases. Research of root system dynamics in Populus species is expanding, however, our understanding of the nature and role of fine roots (FR) is incomplete. The study objective, therefore, was to review the literature regarding FR production, mortality and longevity in Populus, and evaluate the magnitude and significance of the FR fraction to C sequestration. FRs, conventionally defined as less than 2 mm in diameter and responsible for water and nutrient uptake, are an essential component of the tree. Populus FRs are relatively short-lived, with reported lifespans ranging from 30 to 300 days, depending on root diameter, tree species and age, and soil environmental factors. Standing FR biomass fluctuates throughout the growing season. Fine root production generally peaks in mid-summer, and ranges between 1.0 and 5.0 mg ha−1 yr−1, while FR mortality has less seasonal amplitude. Production and mortality dynamics in Populus are highly plastic in response to soil environmental conditions, and although opposing conclusions have been proposed, research suggests soil moisture and nitrogen to be most important. Results from the literature indicate annual FR turnover to the soil C pool may be small (0.2–1.6 mg C ha−1 yr−1), but substantial in maintaining or enhancing C levels in natural and managed stands of Populus.  相似文献   
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