果菜类蔬菜早熟性育种研究进展

早熟性是蔬菜作物育种的重要指标,对农业增产和农民增收意义重大。本文对果菜类蔬菜早熟性评价指标,早熟性相关农艺性状和早熟性育种方法三个方面的研究进展进行综述,并对基因工程辅助早熟育种进行了展望。     

Effect of Se and VE Supplement on Semen Quality,Antioxidant Enzyme Activities and Heat Shock Protein Expression of Goat in High Temperature Season

This experiment was conducted to study the effect of selenium and vitamin E supplement on semen quality, antioxidant enzyme activities and heat shock protein expression of goat in Hainan high temperature season.16 adult Hainan Black goat with good health and approximate weight were randomly divided into 4 groups, fed with basal diet(control group), basal diet+0.5 mg/kg Se(Se group), basal diet+100 mg/kg VE(VE group), and basal diet+0.5 mg/kg Se+100 mg/kg VE(Se+VE group), respectively.The experimental period was 93 d.Semen samples were collected in the last week of the experiment on two consecutive days.The semen quality, antioxidant enzyme activities and heat shock protein expression were analyzed.The results showed that compared with control group, the ejaculate volume was not significantly affected by Se or VE supplement(P>0.05).Sperm density and sperm motility were increased significantly by Se and VE supplement(P<0.05), and the abnormal rate was decreased extremely significantly(P<0.01).The goats fed with Se and VE also had higher activities of GSH-Px(P<0.01), SOD(P<0.05), CAT(P<0.05) and T-AOC(P<0.01), and lower MDA concentration in seminal plasma(P<0.05).The relative expression levels of HSP70 and HSP90 mRNA in supplement groups were decreased extremely significantly(P<0.01).However, there were some certain differences between the Se and VE supplement groups on semen quality and heat shock protein expression.In conclusion, the supplementation of Se and VE could help to improve goat semen quality by increasing the sperm density, sperm motility, the antioxidant enzyme activities, and decreasing the abnormal rate in hot season of Hainan.Finally, Se and VE supplement had good effects on relieving the environment heat stress.     

水分胁迫对'赤霞珠'葡萄不同叶龄叶片糖含量及相关代谢酶活性的影响

以三年生'赤霞珠'葡萄为试材,通过控制灌溉量,以黎明前叶片水势(ψb)反映胁迫程度,设置无水分胁迫、中度水分胁迫和重度水分胁迫3个处理,研究了'赤霞珠'葡萄新梢基部(叶1)、下部(叶2)、中部(叶3)、中上部(叶4)、上部(叶5)叶片的糖含量及其相关代谢酶活性,以期明确水分胁迫对'赤霞珠'葡萄不同叶龄叶片糖含量及其相关代谢酶活性的影响.结果 表明:中度水分胁迫处理下,葡萄新梢不同叶龄叶片蔗糖、可溶性糖含量均高于对照组,处理前期还原糖含量低于对照组;处理中后期还原糖含量高于对照组;重度水分胁迫处理下,葡萄新梢不同叶龄叶片蔗糖含量低于对照组、还原糖含量高于对照组;在处理前期,叶3～5可溶性糖含量高于对照组,后期各叶龄叶片可溶性糖含量逐渐低于对照组;中度水分胁迫可以提高叶3～5叶片蔗糖磷酸合成酶(SPS)活性,而重度水分胁迫降低了不同叶龄叶片蔗糖磷酸合成酶(SPS);水分胁迫可以提高叶3～5叶片中性转化酶(NI)活性、不同叶龄叶片蔗糖合成酶(SS)和酸性转化酶(AI)活性;中度水分胁迫有利于不同叶龄叶片糖分的积累及相关代谢酶活性的提高.     

高通量测序解析冰鲜刀鲚细菌群落变化特征

为了研究养殖刀鲚冰鲜保存过程中细菌群落组成及变化情况,采用Illumina Miseq高通量测序方法对冰鲜条件不同贮藏时间（0、3、6、9、12、15、18 d）刀鲚肌肉样本细菌的16S rRNA基因的2个高变区（V3—V4）进行测序,比较其细菌多样性及门、属水平的细菌相对丰度,并进行主成分分析、Heatmap分析以及特定腐败菌分析。结果显示,7组样品细菌分布于40门787属,冰鲜条件下刀鲚肌肉的优势致腐败菌属为假单胞菌、微杆菌属和气单胞菌属。主成分分析显示,刀鲚腐败前后的微生物结构存在差异。Heatmap图分析显示新鲜样本的细菌丰度最大。3组冰鲜贮藏6 d前的样品群落结构较相似。贮藏12 d时常见致腐菌（微杆菌属、假单胞菌属、气单胞菌属）占比显著提高,其细菌的多样性及丰富度最低。随着冰鲜保存时间的延长,刀鲚肌肉的细菌菌落结构产生了动态变化。冰鲜保存6～9 d后刀鲚肌肉的细菌菌落结构变化较大,研究结果可以为预测冰鲜刀鲚货架期提供参考。     

基于多元统计分析的茄衣烟叶生产气候资源配置

为探究茄衣烟叶生产中的气候资源配置情况,以“云雪1号”品种为试验材料,通过调整移栽期以改变烟株生育期内的气候指标,采用多元统计分析法研究茄衣烟叶的气候资源配置及其对烟株农艺性状及发酵后烟叶化学成分的影响。相关性分析结果显示,烟株大田期的积温、≥10 ℃有效积温、总降水量与总温差对烟株农艺性状各指标的影响较大,其相关系数分布范围为0.478~0.939,而积温、≥10 ℃有效积温、平均气温对烟叶总糖、烟碱、总氮、蛋白质含量影响较大,其相关系数分布范围为-0.955~-1.000。采用因子分析的方法在8项气候指标中提取出气候积累因子与湿度因子2个主因子,进一步通过灰色关联分析得出上述二者分别是影响烟株农艺性状和烟叶常规化学成分的主因子。以上结果表明,确定茄衣烟株移栽期的主要气候因子依据为大田生育期的气温、降水量和相对湿度的综合配置。     

卡利比克迈耶氏酵母对水果采后病害的抑制及对展青霉素的降解机制

为了明确拮抗酵母卡利比克迈耶氏酵母Meyerozyma caribbica对果实采后病害的抑制效果及其对毒素的降解机制, 本文研究了卡利比克迈耶氏酵母结合辅助因子褐藻寡糖(alginate oligosaccharide, AOS), 对草莓、梨、苹果、番茄的青霉病、灰霉病和黑斑病的抑制效果, 以及拮抗酵母不同处理液对展青霉素(patulin, PAT)体外降解的机制。结果表明, 浓度为1×108 cfu/mL的M. caribbica可有效抑制草莓、梨、苹果青霉病, 草莓、番茄、葡萄灰霉病以及番茄、梨、葡萄黑斑病的发生, 添加5 g/L的AOS能显著增强M. caribbica的抑制效果; M. caribbica发酵液可以有效降解苹果伤口处的PAT, 处理后8 d其降解率为30.35%, 经AOS诱导后, 其对PAT的降解效率达到39.15%。体外条件下, 接种M. caribbica后27 h可将10 μg/mL的PAT完全降解; M. caribbica主要是通过活细胞代谢降解PAT, 同时AOS可显著增加M. caribbica 的降解能力, 说明卡利比克迈耶氏酵母是一株生防潜力较好的菌株, 本研究为该生防菌株的进一步应用奠定了基础。     

一株马铃薯干腐病生防菌的鉴定及其抑菌活性研究

镰孢菌引起的马铃薯干腐病是影响马铃薯贮存期间产量与品质的重要病害之一。寻找高效低毒的防治马铃薯干腐病的生防药剂对提高马铃薯的产量与质量具有重要意义。本研究以腐皮镰孢Fusarium solani为病原菌, 测定分离自马铃薯块茎的菌株2-1-9-CJK-2的抑菌活性。该菌株发酵液、无菌发酵液、菌悬液、胞内组分以及挥发性有机物对腐皮镰孢均具有抑菌活性, 抑制率分别为93.37%、61.92%、80.82%、44.01%和49.16%。结合形态学、生理生化特征和多基因系统发育树构建鉴定其为贝莱斯芽胞杆菌Bacillus velezensis。马铃薯切片试验和马铃薯块茎试验表明, 当菌株发酵液浓度为1×109 cfu/mL时, 对病原菌的抑制效果最好。除此之外, 菌株可以分泌蛋白酶、淀粉酶、纤维素酶, 具有溶磷能力和生物膜形成能力, 但不具有溶血性, 并且对供试的其他6种病原真菌有较强的抑菌活性。研究表明贝莱斯芽胞杆菌2-1-9-CJK-2抑菌谱广, 具有生物安全性, 对腐皮镰孢有较强的抑菌活性, 在植物病害防治中具有一定的应用潜力, 可为马铃薯干腐病生防制剂的开发奠定基础。     

龙眼中E进化支多聚半乳糖醛酸酶（PG）基因DlPG1的表达模式与幼果脱落间关系的初步研究

从龙眼中分离获得一个多聚半乳糖醛酸酶（PG）基因,命名为DlPG1。DlPG1基因与多种物种PG基因氨基酸序列有较高的同源性,其中与同属于无患子科的荔枝同源性最高为95%且与荔枝的亲缘关系最近。DlPG1基因包含PG基因特有4个保守区中的3个,DlPG1属于E进化支PG基因家族成员。环剥摘叶处理可以显著促进龙眼幼果脱落,累积落果率在对照中为6.12%,在处理中为89.85%,相对落果率高峰出现在第5 d（处理是对照的188倍）。离区DlPG1基因表达量在处理中始终高于对照,且表达量高峰出现在第4 d（处理是对照的17倍）。基因表达量的高峰早于相对落果率高峰出现,据此推测DlPG1基因可能是调控龙眼幼果脱落的关键基因。到目前为止,DlPG1基因是首例在龙眼中发现的属于E进化支的可能与器官脱落相关的PG基因。     

Sulodexide protects against hyperglycemia-induced retinal vascular injury via suppressing NOX4/NLRP3 pathway

AIM To investigate the effect of sulodexide (SDX) on high glucose-induced damage in retinal microvascular endothelial cells. METHODS (1) High-fat diet combined with intraperitoneal injection of streptozocin were used to induce type 2 diabetes mellitus (DM) followed by injection of saline or SDX in C57BL/6J male mice. Retinal microvascular leakage and density, and the protein levels of NLRP3 inflammasome-related proteins, zonula occludens-1 (ZO-1) and NADPH oxidase 4 (NOX4) were measured. (2) Human retinal microvascular endothelial cells (HRMECs) were treated with normal glucose or high glucose with or without SDX, and were further transfected with siRNA to knock down NOX4, or infected by adenovirus to over-express NOX4. The protein levels of ZO-1, VE-cadherin (VE-Cad), NOX4 and NLRP3 inflammasome-related proteins as well as the level of reactive oxygen species (ROS) were detected. RESULTS Treatment with SDX increased the protein level of ZO-1, attenuated retinal leakage and NLRP3 inflammasome activation, and enhanced the density of microvasculature and the number of ganglion cells in diabetic retinas. The protein levels of ZO-1 and VE-Cad were decreased, while the levels of NOX4, NLRP3 inflammasome-related proteins and ROS generation were increased in high glucose-treated HRMECs. Silencing of NOX4 inhibited high glucose-induced increases in NLRP3 inflammasome and ROS generation, and decreases in the protein levels of ZO-1 and VE-Cad. Over-expression of NOX4 significantly increased the levels of NLRP3 inflammasome-related proteins and ROS generation in HRMECs, and reduced the protein levels of ZO-1 and VE-Cad. Treatment with SDX partly reversed NOX4 over-expression-induced changes. CONCLUSION SDX alleviates hyperglycemia-induced retinal microvascular endothelial injury via inhibiting NOX4/ROS/NLRP3 pathways.