大豆Abhydrolase_3基因家族进化分析

异黄酮是大豆的重要次生代谢物,参与植物与微生物互作。2-羟基异黄酮脱水酶(hydroxyisoflavanone dehydratase,HID)催化2-羟基异黄酮形成稳定的异黄酮。HID属于Abhydrolase_3基因家族,该基因家族具有多种功能,但该基因家族在大豆中的进化模式尚待研究。为了研究Abhydrolase_3基因家族在大豆中的进化模式,本文在大豆基因组中鉴定了62个Abhydrolase_3基因,串联和片段复制是该基因家族主要扩增方式。根据系统进化关系,将大豆Abhydrolase_3基因家族划分为8个亚家族,其中HID所在的亚家族I基因数量最多,并发生多次基因扩增事件。对大豆Abhydrolase_3基因家族结构分析表明,不同亚家族具有不同的基序。多态性分析表明,亚家族Ⅰ、Ⅲ和Ⅴ具有较高的核苷酸差异,并受到放松的自然选择。基因表达分析表明,除了亚家族II和IV外,其它亚家族的基因在大豆不同组织中有较高表达;亚家族Ⅰ、Ⅲ、Ⅳ、Ⅴ和Ⅵ基因受病原菌诱导表达。结果说明HID所在的亚家族I存在基因扩增和功能分化,与病原菌互作相关的基因具有较高的遗传多样性并受病原菌诱导表达。     

河北省长针线虫新纪录种松长针线虫Longidorus pinus Xu,Ye,Wang&Zhao的形态与分子鉴定

2018 年,在河北省保定市园林植物紫荆（Cercis chinensis）根围分离到一种长针线虫。经形态 学观察和 28S rDNA D2D3 区序列分析,将其鉴定为松长针线虫（Longidorus pinus Xu, Ye, Wang & Zhao）。 其雌虫主要形态特征为：雌虫体长 3 048~3 464 μm,唇区明显缢缩,宽 9.5~10.5 μm,侧器囊袋状,齿尖 针长 66.0~69.5 μm,导环距体前端 27.5~30.0 μm,尾长 31~33 μm,短圆锥形,尾长与肛门处体宽比值＝ 1.5~1.6。松长针线虫河北种群 28S rDNA D2D3 区与 GenBank 数据库的山西种群进行序列比对,相似性为 99.2%~99.9%。松长针线虫是河北省长针线虫新纪录种。紫荆是松长针线虫的新寄主。     

Epigallocatechin-3-gallate suppresses hemin-aggravated colon carcinogenesis through Nrf2-inhibited mitochondrial reactive oxygen species accumulation

BackgroundPrevious studies have presented evidence to support the significant association between red meat intake and colon cancer, suggesting that heme iron plays a key role in colon carcinogenesis. Epigallocatechin-3-gallate (EGCG), the major constituent of green tea, exhibits anti-oxidative and anti-cancer effects. However, the effect of EGCG on red meat-associated colon carcinogenesis is not well understood.ObjectivesWe aimed to investigate the regulatory effects of hemin and EGCG on colon carcinogenesis and the underlying mechanism of action.MethodsHemin and EGCG were treated in Caco2 cells to perform the water-soluble tetrazolium salt-1 assay, lactate dehydrogenase release assay, reactive oxygen species (ROS) detection assay, real-time quantitative polymerase chain reaction and western blot. We investigated the regulatory effects of hemin and EGCG on an azoxymethane (AOM) and dextran sodium sulfate (DSS)-induced colon carcinogenesis mouse model.ResultsIn Caco2 cells, hemin increased cell proliferation and the expression of cell cycle regulatory proteins, and ROS levels. EGCG suppressed hemin-induced cell proliferation and cell cycle regulatory protein expression as well as mitochondrial ROS accumulation. Hemin increased nuclear factor erythroid-2-related factor 2 (Nrf2) expression, but decreased Keap1 expression. EGCG enhanced hemin-induced Nrf2 and antioxidant gene expression. Nrf2 inhibitor reversed EGCG reduced cell proliferation and cell cycle regulatory protein expression. In AOM/DSS mice, hemin treatment induced hyperplastic changes in colon tissues, inhibited by EGCG supplementation. EGCG reduced the hemin-induced numbers of total aberrant crypts and malondialdehyde concentration in the AOM/DSS model.ConclusionsWe demonstrated that EGCG reduced hemin-induced proliferation and colon carcinogenesis through Nrf2-inhibited mitochondrial ROS accumulation.     

Modelling the variability of UK sugar beet yields under climate change and husbandry adaptations

In the future, UK summers are likely to be warmer and drier. Modelling differential water redistribution and uptake, we assessed the impact of future drier climates on sugar beet yields. Weather was generated for 1961–1990 (BASE) and predictions based on low‐ and high‐emission scenarios (LO, HI) described in the most recent global climate simulations by the Hadley Centre, UK. Distributions and variability of relative soil moisture deficit (rSMD) and yield gap (drought‐related yield loss, YG_dr = 1?actual yield/potential yield), and sugar yield were calculated for different time‐lines using regional weather, soil texture and management inputs. The rSMD is estimated to exceed the senescence threshold with a probability of 75% (2050sLO) to 95% (2080sHI) compared with 65% (BASE). The potential yield loss, YG_dr, is likely to increase from 17% (BASE) to 22% (2050sLO) to 35% (2080sHI). However, increasing potential growth rates (CO₂ × temperature) cause average sugar yields to rise by between 1.4 and 2 t ha^?1 (2050sLO and 2050sHI respectively). Yield variation (CV%) may increase from 15–18% (BASE) to 18–23% (2050s) and 19–25% (2080s). Differences are small between regions but large within regions because of soil variability. In future, sugar yields on sands (8 t ha^?1) are likely to increase by little (0.5–1.5 t ha^?1), but on loams yields are likely to increase from 11 to 13 t ha^?1 (2050sHI) and 15 t ha^?1 (2080sHI). Earlier sowing and later harvest are potential tools to compensate for drought‐related losses on sandy soils.     

Effect of IAA and GA3 on the Anatomical Characteristics, Straw and Fiber Yield and Quality of Flax

IAA and GA₃ had increased the stem thickness by increasing that of cortex, phloem fibers and xylem. Each had increased straw and fiber yield/plant, but the effect was more pronounced with GA₃ than IAA. The percentage of long fibers, strength and fineness increased significantly with GA₃. The latter two properties decreased with IAA.     

宁杂棉3号在国家棉花品种展示试验中的表现及栽培技术

通过试验表明：宁杂棉3号具有高产（357.6kg/667m2）、早熟的特点,适应在苏北沿海地区推广。栽培技术上强调科学施肥、化控及防病治虫。     

磷素营养对星星草幼苗抗碱性的影响

通过以不同水平磷素营养培养星星草幼苗，研究磷素营养对星星草幼苗抗碱性的影响，试验结果表明：在２．０％Ｎａ２ＣＯ２胁迫下星星草苗磷素营养的最适浓度为２．８ｍｍｏｌ·Ｌ＾－１ＫＨ２ＰＯ４，此条件下仅对株高，干重和鲜重的增长有促进作用，而且受害程度最小，对Ｎａ２ＣＯ３胁迫的缓解作用最强，在一定程度上可提高星星草幼苗对Ｎａ２ＣＯ３胁迫的抗性。     

野牛草种子休眠机理初探

以野牛草为试材，在颖苞解剖结构观察以及吸胀测定的基础上进行了剥除颖苞后的０．２％ＫＮＯ３低温预处理和ＧＡ３、乙烯利两种激素前处理。前处理后在８０℃恒温和３０～１０℃变温条件下测定种子发芽率及淀粉酶活性。结果表明，野牛草种子是综合休眠型；聚合颖苞的吸水通常在置床后７２小时只能达到颖果干重的２６％，而剥去颖苞的颖果在置床后３４小时吸水量可达该种子萌发水分含量的下限即４０％；连种单位中的颖果之间没有相互抑制作用，各自的休眠与萌发是独立的。在０．２％ＫＮＯ３溶液中预冷一周，然后在１０～３０℃变温条件下萌发，其发芽率可达８５％。１５０ｍｐ／Ｌ的ＧＡ３外源激素处理可以代替ＫＮＯ３冷冻预处理。种子萌发过程中β－淀粉酶与α－淀粉酶有协同作用。     

放牧牦牛瘤胃生理指标的测定

在莎草科 禾本科草地上对放牧条件下牦牛瘤胃几种生理指标进行测定。结果表明，在1天中8：00时瘤胃温度显著(P＜0．01)低于20：00时，8：00时瘤胃pH值显著(P＜0．01)高于20：00时，氨氮含量差异不显著。1天中瘤胃pH有两个高峰，分别出现在6：00和10：00，午后转入低谷；瘤胃温度表现为白天高于晚上，最大值出现在12：00；氨氮含量变化波动很大，l天内出现多个峰值，最高峰出现在10：00，也表现出白天高晚上低的趋势。     

Micropropagation of Cryptanthus with leaf explants with attached intercalary meristems excised from greenhouse stock plants

By using the leaves with attached intercalary meristems from greenhouse grown stock plants, five cultivars of Cryptanthus were cultured on modified MS media with 4.5 μM NAA and IBA and 3 μM BA to induce adventitious shoot formation from callus tissue. Contamination was 17–21% for explants taken from stock plants which were sprayed weekly with Agribrom and 27–75% for those taken from stock plants which were not treated. More than 99% true to type plantlets were obtained from non-chimeric plants. Green and albino plantlets were obtained from chimeric plants. The chimeric C. ‘Coster's Favorite’ DeCoster also produced a few chimeric plantlets with intermarginal pink stripes in addition to the green and albino plantlets. Most of the non-chimeric plants took a shorter time to produce plantlets of transplantable size (8–12 mm) than the chimeric ones. Except for albino plantlets, survival rate of plantlets exceeded 95%. A minimum average of 500 rooted plantlets can be obtained in a year from a single well-callused leaf explant. The protocol in this report should speed up the mass production and introduction of desirable new cultivars and hybrids of non-chimeric Cryptanthus.