利用荧光观测明确载球孢白僵菌松毛虫赤眼蜂对亚洲玉米螟的防控增效作用

载球孢白僵菌松毛虫赤眼蜂能够显著提高对亚洲玉米螟的防控效果，为了明确其对亚洲玉米螟卵期及幼虫期可持续防控的作用机理，采用松毛虫赤眼蜂吸附绿色荧光蛋白（GFP）标记的球孢白僵菌分生孢子，进行赤眼蜂载菌情况，以及亚洲玉米螟卵和幼虫的寄生、侵染过程观察。结果表明，赤眼蜂羽化后能够吸附柞蚕卵表面粘附的白僵菌分生孢子，并将其携带至亚洲玉米螟卵块表面，并吸附于未被赤眼蜂寄生的亚洲玉米螟卵孵化的幼虫体表，实现侵染并致死，幼虫带菌率达60.00%，网室内杀虫生物测定僵虫率达27.00%。本研究表明，载菌赤眼蜂在提高杀虫效率的同时实现害虫可持续防控，该方法为其他载菌天敌的应用提供了依据。     

桃蚜电压门控钠离子通道基因cDNA克隆及其生物信息学分析

克隆获得桃蚜电压门控钠离子通道基因cDNA序列，明确钠离子通道的典型特征，为研究桃蚜抗性分子机理奠定基础。采用实验技术主要有RT-PCR和PCR，克隆桃蚜钠离子通道基因cDNA序列，利用相关软件对其序列进行生物信息学分析。克隆得到两段cDNA序列MpNa_v-1（NCBI登录号：MN124170）和MpNa_v-2（NCBI登录号：MN176136）。MpNa_v-1长度为2945 bp，包括2877 bp的完整开放阅读框，共编码958个氨基酸；MpNa_v-2长度为3546 bp，包括3486 bp的完整开放阅读框，共编码1161个氨基酸。MpNa_v-1和MpNa_v-2共同组成桃蚜的钠离子通道α亚基，MpNa_v-1包含同源结构域Ⅰ和同源结构域Ⅱ，MpNa_v-2包含同源结构域Ⅲ和同源结构域Ⅳ。同源比对发现，桃蚜与豌豆蚜和高粱蚜钠离子通道基因相似度分别高达97.67%和97.65%，所克隆序列包含昆虫钠离子通道α亚基典型特征，具有MFM模块，并含有蚜虫类钠通道特有模块DENS。成功地克隆桃蚜钠离子通道基因，为阐明其对拟除虫菊酯类药剂产生靶标抗性的分子机制奠定基础。     

Genome-wide detection of selective signatures in a Jinhua pig population

The aim of this study was to detect evidence for signatures of recent selection in the Jinhua pig genome. These results can be useful to better understand the regions under selection in Jinhua pigs and might shed some lights on groups of genes that control production traits. In the present study, we performed extended haplotype homozygosity(EHH) tests to identify significant core regions in 202 Jinhua pigs. A total of 26 161 core regions spanning 636.42 Mb were identified, which occupied approximately 28% of the genome across all autosomes, and 1 158 significant(P0.01) core haplotypes were selected. Genes in these regions were related to several economically important traits, including meat quality, reproduction, immune responses and exterior traits. A panel of genes including ssc-mir-365-2, KDM8, RABEP2, GSG1L, RHEB, RPH3AL and a signal pathway of PI3K-Akt were detected with the most extreme P-values. The findings in our study could draw a comparatively genome-wide map of selection signature in the pig genome, and also help to detect functional candidate genes under positive selection for further genetic and breeding research in Jinhua and other pigs.     

南瓜饲养榕树粉蚧的发育历期与生物学特征初报

榕树粉蚧是一种重要的入侵害虫,对果蔬和园林植物存在巨大的潜在威胁。为满足开展检疫处理、防控、生物学和生理学等研究的需要,本研究以南瓜为饲养材料,在室温条件下(26±1℃,RH 65%±5%)观察榕树粉蚧的生物学特性与发育历期。结果表明,榕树粉蚧具有典型的雌雄二型现象。雄虫主要经历卵、12龄若虫、预蛹、蛹、雄成虫阶段;雌虫经历卵、13龄若虫、雌成虫(产卵前期、产卵期)阶段,其发育历期(mean±SE)分别为8.51±0.03 d、9.79±0.09 d、7.46±0.10 d、6.52±0.11 d、12.13±0.11 d、8.16±0.11 d,世代发育历期54.4±0.25 d。雌成虫产卵量483651粒,平均550.87±51.07粒,卵期711 d,孵化率95.19%±0.75%。该研究结果表明榕树粉蚧繁殖能力强,应高度重视其防控工作。     

Quantitative trait loci analysis for root traits in synthetic hexaploid wheat under drought stress conditions

Synthetic hexaploid wheat(SHW), possesses numerous genes for drought that can help breeding for drought-tolerant wheat varieties. We evaluated 10 root traits at seedling stage in 111 F9 recombinant inbred lines derived from a F2 population of a SHW line(SHW-L1) and a common wheat line, under normal(NC) and polyethylene glycol-simulated drought stress conditions(DC). We mapped quantitative trait loci(QTLs) for root traits using an enriched high-density genetic map containing 120 370 single nucleotide polymorphisms(SNPs), 733 diversity arrays technology markers(DArT) and 119 simple sequence repeats(SSRs). With four replicates per treatment, we identified 19 QTLs for root traits under NC and DC, and 12 of them could be consistently detected with three or four replicates. Two novel QTLs for root fresh weight and root diameter under NC explained 9 and 15.7% of the phenotypic variation respectively, and six novel QTLs for root fresh weight, the ratio of root water loss, total root surface area, number of root tips, and number of root forks under DC explained 8.5–14% of the phenotypic variation. Here seven of eight novel QTLs could be consistently detected with more than three replicates. Results provide essential information for fine-mapping QTLs related to drought tolerance that will facilitate breeding drought-tolerant wheat cultivars.     

爱媛28’香橙砧与枳砧在南平市引种表现与评价

2017年引进早熟杂柑品种‘爱媛28’香橙砧和枳砧苗分别在大棚设施和露天进行试种，栽培4年调查比较两个砧木组合的生长表现、丰产性与果实品质，结果表明：‘爱媛28’香橙砧树表现生长势强，冠幅、树高、茎粗、结果枝、秋梢等生长量指标显著大于枳砧树，3a树初产1436 kg/667㎡，4a树2523kg/667㎡，显著高于枳砧4a树初产1809kg/667㎡；大棚种植香橙砧4a树果实10月下旬TSS11-12%，12月中旬TSS可达15%，与枳砧相当，可滴定酸比枳砧略高，两者固酸比均达18以上，口感风味极佳，两者单果重、果形指数、果皮厚度、可食率无显著性差异；未密封大棚4a树体经受2020年寒冬极端低温考验无明显冻害，抗旱抗寒能力中等，易感黑点病和流胶病，大棚种植能很好预防黑点病。综合评价爱媛28枳砧和香橙砧均适合在南平市种植，香橙砧比枳砧早期丰产性稳产性好，收益更高，香橙砧‘爱媛28’设施种植较枳砧更具优势。     

陕北黄土区退耕还林(草)地土壤质量特征及其对降水的响应

为了解陕北黄土区退耕还林（草）地土壤质量差异特征及其对降水的响应，该文沿370～470 mm的降水梯度，选取了陕西省吴起县境内的王洼子（370～395 mm）、大吉沟（440～445 mm）和白豹（460～470 mm）3个降水梯度区作为研究区，并结合土壤质量指数法，定量评价降水梯度区广泛栽植的刺槐林（Robinia pseudoacacia）、沙棘林（Hippophae rhamnoides）和草地的土壤物理结构、持水性、盐碱度、碳汇指标以及速效养分指标方面的综合得分，明确植被恢复后土壤质量随降水梯度的变化特征。结果表明：1）降水量、植被类型以及二者的交互作用对土壤指标影响显著（P<0.05）。2）在460～470 mm降水量区，刺槐林（0.829）对土壤质量改良效果最好，其次为沙棘林（0.808），二者土壤质量均达到肥沃水平，且差异不显著，草地（0.679）土壤质量指数最低，土壤为较肥沃水平；在440～445 mm降水量区，沙棘林（0.74）对土壤改良效果最好，其次为刺槐林（0.601），二者均达到较肥沃水平，草地（0.479）土壤质量指数最低为中等水平；在370～395 mm降水量区，3种植被类型土壤质量指数由大到小表现为沙棘林（0.744）>刺槐林（0.387）>草地（0.251），沙棘林土壤质量等级为较肥沃、刺槐林和草地为贫瘠水平。3）在370～470 mm降水梯度内，3种植被类型土壤质量综合指数均随着降水量的减少而降低，其中沙棘林土壤质量指数变异性较低（4.1%），刺槐林（30.1%）和草地（37.2%）土壤质量变异性较高。该研究结果可为陕北黄土区370～470 mm降水梯度下的植被恢复与重建等林业生态工程实施提供数据支撑与理论支持。