抗小贯松村叶蝉和茶棍蓟马的茶树种质筛选及其抗性相关因素分析

探讨不同茶树品种对小贯松村叶蝉（Matsumurasca onukii）和茶棍蓟马（Dendrothrips minowai Priesner）的抗性,为抗虫茶树品种的选育和推广提供科学依据。以11个茶树品种紫娟、水仙、梅占、白鸡冠、瑞香、奇兰、黄玫瑰、白牡丹、黄棪、大红袍、黄观音为供试材料,采用五点取样法对田间种群密度进行调查,并进行茶树植物学形态特征调查,以及叶片组织结构测定、化学成分检测,明确茶树物理性状、化学成分与抗虫性之间的相关性。结果显示,按抗小贯松村叶蝉的强弱,11个茶树品种可分为4类,第Ⅰ类：紫娟,感虫（S）;第Ⅱ类：梅占、黄棪、奇兰、水仙、白牡丹,中感（MS）;第Ⅲ类：瑞香、大红袍、黄观音、黄玫瑰,中抗（MR）;第Ⅳ类：白鸡冠,抗（R）。按抗茶棍蓟马的强弱也可将其分为4类,第Ⅰ类：黄玫瑰,感虫（S）;第Ⅱ类：瑞香、白鸡冠,中感（MS）;第Ⅲ类：黄观音、奇兰,中抗（MR）;第Ⅳ类：白牡丹、黄棪、大红袍、梅占、紫娟、水仙,抗（R）。结合相关分析显示,小贯松村叶蝉总虫口数与11个茶树品种的花青素含量、GCG含量呈极显著正相关（P<0.01）,与上角质层厚度/叶片厚度、下角质层厚度/叶片厚度呈显著正相关（P<0.05）,而与游离氨基酸总量、栅栏组织厚度、上表皮厚度、上表皮厚度/叶片厚度呈显著负相关（P<0.05）。叶长与茶棍蓟马总发生量呈显著负相关（P<0.05）,且小贯松村叶蝉的总虫口数与茶棍蓟马总虫口数显著负相关（P<0.05）。综合分析得出,大红袍茶树品种和黄观音茶树品种对小贯松村叶蝉和茶棍蓟马均存在一定抗性,是值得推广的茶树良种。调查结果还发现小贯松村叶蝉和茶棍蓟马之间存在同期交替为害茶树的现象。     

茶叶浸取液制备的纳米银对土壤微生物的影响

为探究茶叶浸取液制备的纳米银对土壤微生物的生物安全性的影响,本研究利用植物还原法制备纳米银抗菌材料,并将其制成1000 mg/L的纳米银喷雾,分析其对土壤微生物多样性及丰富度的影响。结果表明：空白对照组(CK)与实验组(Nano-Ag)的样本土壤中,所具有的微生物类别基本一致,但是不同类别微生物的丰度具有一定差异。实验组和对照组的Coverage数值均较高(Coverage>99.71%),香农指数均较大(Shannon>5.46),辛普森指数均较小(Simpson<0.02),两组间ACE指数和Chao指数差异均较小(ACE<2,Chao<6);同时,纳米银可抑制变形菌门下的α-变形菌纲和放线菌门下的嗜热油菌纲的生长,而能够促进绿弯菌门下纤线杆菌纲的生长。本文验证了纳米银具有一定程度的生物安全性,拓宽了纳米银材料的潜在应用范围,为纳米材料在环境及医疗等领域的深入应用奠定了基础。     

转cry30Fa1水稻对褐飞虱NlHRP基因表达模式的影响

转cry30Fa1水稻（KF30-14）会显著控制褐飞虱Nilaparvata lugens (Stål)种群数量增长,但其影响机制尚不清楚。本研究利用相关转录组数据分析筛选获得了一个表达量有显著差异的基因NlHRP,并克隆了该基因。序列分析表明,NlHRP编码了一个富组氨酸蛋白,无保守结构域。通过实时荧光定量PCR检测羽化24、72、96 h的褐飞虱雌虫的NlHRP表达量,结果显示该基因在KF30-14褐飞虱实验种群中的表达量均高于MH86实验种群,且在羽化72 h时,达到显著差异;对羽化后72 h褐飞虱雌虫的头、胸、卵巢、中肠、脂肪体的NlHRP表达量检测发现,NlHRP在褐飞虱的头、胸、中肠表达量较高,其中KF30-14褐飞虱实验种群雌虫的NlHRP在头部表达量显著升高。推测NlHRP可能与褐飞虱适应转cry30Fa1水稻的抗性有关,该研究结果为揭示转cry30Fa1水稻抗褐飞虱的分子机制提供相关基础。     

不同堆青时间对白茶风味品质的影响

以不同堆青时间的白茶样品为研究对象,结合感官审评和生化成分检测,探究不同堆青时间对白茶风味品质的影响。生化分析结果表明,随着堆青时间的增加,茶汤的苦味和涩味先减弱后增强,甜度先升高后下降,醇度逐步提升,白茶青气消退、甜花香凸显。茶多酚、黄酮、可溶性糖、儿茶素和游离氨基酸含量的变化是滋味差异的主要原因。顺式芳樟醇氧化物（呋喃型）、反式芳樟醇氧化物（呋喃型）、癸醛、α-萜品醇、β-环柠檬醛、香叶基丙酮、β-紫罗兰酮、正辛醛等香气化合物含量的变化是形成香气差异的关键。不同堆青时间处理下,堆青12 d茶样的风味品质最佳,既有利于游离氨基酸、可溶性糖、儿茶素含量的增加,也能最大限度降低茶汤中的苦涩味指数,同时提高反式芳樟醇氧化物（呋喃型）、癸醛、β-环柠檬醛、香叶基丙酮、β-紫罗兰酮等香气化合物的含量,促进白茶中甜香和花香的形成。本研究可为白茶堆青工艺优化及风味品质的提升提供一定借鉴和参考。     

Induction of heat shock protein genes by chlorfenapyr in cultured cells of the cabbage armyworm,Mamestra brassicae

Effects of structurally different insecticides, permethrin, chlorfluazuron, chlorfenapyr, prothiofos, methomyl, and thiocyclam on expression of hsp90, hsp70, hsp20.7, and hsp19.7 were examined using cultured cells of the cabbage armyworm, Mamestra brassicae. Significant induction of hsp90, hsp70, hsp20.7, and hsp19.7 expression was observed in response to chlorfenapyr. No induction was observed for the remaining five insecticides. The chlorfenapyr-induced expression was time-dependent and concentration-dependent. A significant reduction in expression levels of hsp70, hsp20.7, and hsp19.7 was observed in the time course when the cells exposed to chlorfenapyr were transferred to chlorfenapyr-free medium. These results suggest that hsp70, hsp20.7, and hsp19.7 might be useful to assess cellular distress or injury by chlorfenapyr.     

水稻锯齿叶矮缩病毒对褐飞虱生长发育和生殖的影响

为明确水稻锯齿叶矮缩病毒（rice ragged stunt virus,RRSV）对褐飞虱Nilaparvata lugens生长发育和生殖的影响,分别比较带毒褐飞虱与未带毒褐飞虱的若虫发育历期、成虫寿命、性比、翅型及产卵量,并利用实时荧光定量PCR（real-time quantitative PCR,RT-qPCR）技术分析RRSV侵染后褐飞虱体内卵黄原蛋白（vitellogenin,Vg）与其受体（vitellogenin receptor,VgR）以及海藻糖代谢途径中相关基因表达量的情况。结果显示,带毒褐飞虱的若虫历期显著高于未带毒褐飞虱的若虫历期,分别为17.56 d和15.90 d;带毒褐飞虱的成虫寿命、雌虫比例和短翅比例均高于未带毒褐飞虱的,但两者间均无显著差异;带毒褐飞虱较未带毒褐飞虱单雌日产卵量显著提升,分别为11.26粒和6.45粒;带毒褐飞虱的Vg、VgR和海藻糖转运蛋白基因（trehalose transporter,TRET）表达量均显著高于未带毒褐飞虱的。表明RRSV侵染会显著延长褐飞虱若虫发育历期,同时可能通过上调Vg、VgR以及TRET的表达量以促进褐飞虱生殖。     

Identification of chorion genes and RNA interference-mediated functional characterization of chorion-1 in Plutella xylostella

Choriogenesis is the last step of insect oogenesis, a process by which the chorion polypeptides are produced by the follicular cells and deposited on the surface of oocytes in order to provide a highly specialized protective barrier to the embryo. The essential features of chorion genes have yet to be clearly understood in the diamondback moth, Plutellaxylostella, a worldwide Lepidoptera pest attacking cruciferous crops and wild plants. In this study, complete sequences for 15 putative chorion genes were identified, and grouped into A and B classes. Phylogenetic analysis revealed that both classes were highly conserved and within each, branches are also species-specific. Chorion genes from each class were located in pairs on scaffolds of the P. xylostella genome, some of which shared the common promoter regulatory region. All chorion genes were highly specifically expressed in the P. xylostella adult females, mostly in the ovary with full yolk, which is a crucial period to build the shells of the eggs. RNAi-based knockdown of chorion-1, which is located on the Px_scaffold 6 alone, although had no effect on yolk deposition, resulted in smaller eggs and sharply reduced hatchability. Additionally, inhibition of PxCho-1 expression caused a less dense arrangement of the columnar layers, reduced exochorion roughness and shorter microvilli. Our study provides the foundation for exploring molecular mechanisms of female reproduction in P. xylostella, and for making use of chorion genes as the potential genetic-based molecular target to better control this economically important pest.     

Front Cover Image

The cover image is based on the Research Article Potential of entomopathogenic nematode-infected insect cadavers for the biocontrol of the red imported fire ant Solenopsis invicta by Sheng-Yen Wu et al., https://doi.org/10.1002/ps.7637 .

     

茶多酚对农杆菌介导的植物遗传转化体系的影响

为研究在农杆菌介导的茶树遗传体系中,茶多酚对农杆菌侵染效率的影响,以LBA4404、EHA105、ATCC15834和K599 4个农杆菌菌株为研究对象,分析其在不同浓度茶多酚处理下的耐酚能力、被膜完整率、吸附性、vir和chv基因表达,以及遗传转化差异。结果显示,4个菌株的耐酚能力依次为LBA4404>K599>EHA105>ATCC15834,其中EHA105和ATCC15834菌株对茶多酚较为敏感;ATCC15834菌株被膜完整率与茶多酚的浓度、静置时间呈负相关,EHA105在600 mg·L^-1茶多酚处理48 h后,其被膜完整率最低;ATCC15834和EHA105对烟草叶肉细胞的吸附能力随着茶多酚浓度的升高而降低,在经茶多酚处理24 h后,ATCC15834中chvB和EHA105中chvB2的表达受到显著抑制,virA表达量与低浓度酚类的敏感性呈正相关性;烟草经农杆菌菌液（含茶多酚）侵染后,瞬时转化效率和稳定转化效率均受到不同程度的抑制,发状根诱导率大大降低。1 000 mg·L^-1茶多酚处理后,ATCC15834的发根诱导率最低,仅为13.85%,坏死率高达33.85%。综上所述,茶多酚会降低农杆菌活力和被膜完整率,chv基因通过降低表达量影响其吸附性,最终导致烟草转化体系中瞬时转化效率和稳定转化效率均受到不同程度的抑制。