4个高羊茅品种幼苗期抗旱性比较研究

本试验以4个不同品种的高羊茅为材料,在幼苗期对其进行5种不同水势(0MPa、-0.3MPa、-0.6MPa、-0.9MPa、-1.2MPa)的PEG-6000人工模拟干旱胁迫,从丙二醛(MDA)、脯氨酸(Pro)和类胡萝卜素(Car)含量以及抗氧化保护酶活性等几个生理生化指标着手,对其抗旱性进行了对比研究.试验数据表明,随着干旱胁迫的加剧,高羊茅幼苗叶片中MDA、Pro和Car含量呈上升趋势;超氧化物歧化酶(SOD)活性呈先降后升的趋势,而过氧化物酶(POD)活性呈先升后降的趋势.同时发现,高羊茅幼苗期的耐旱极限范围可能在-0.9MPa水势左右.最后利用综合聚类分析法得出这4个高羊茅品种的抗旱性强弱为:贝克的抗旱性较强,家园的抗旱性较弱,火凤凰和爱瑞3的抗旱性一般.     

Identification of a gene responsible for the 60-day delay in flowering time of Arabidopsis

Identification of genes related to flowering-time in Arabidopsis is very important and meaningful contribution to the flowering process control. One late flowering mutant plant, which exhibits 60-day delay in flowering, was screened from Arabidopsis library of T-DNA insertion. Southern blotting was used to confirm the single copy of exogenetic T-DNA in the genome of the mutant. The flanking sequence of T-DNA insert was obtained by TAIL-PCR and then analyzed by BLAST to confirm that the insertion site locates at the sixth exon of AT2G19520.1 (FVE gene). FVE is considered as a classical flowering time gene in Arabidopsis. It is a component of the autonomous pathway that encodes AtMSI4, which is a putative retinoblastoma-associated protein. The late-flowering mutant is named as fve-4, which is similar to fve-3 of Columbia and allelic with fve-1 and fve-2 of Landsberg erecta. The fve-4 mutant’s delay of flowering was longer than that of fve-3 mutant, whose T-DNA insertion is located at the first exon of FVE gene, suggesting that the sixth exon of FVE gene may play a more important role in the control of floral transition.     

Screening of conidium development mutant of Botrytis cinerea and functional analysis of the related gene

A novel conidium development mutant was obtained by screening the transformants of Botrytis cinerea produced by Agrobacterium tumefaciens mediated method, which lost the ability of producing conidia. The flanking sequence of T-DNA insertion site was acquired by TAIL-PCR technology, and then, the T-DNA insertion in the second exon of BC1G_02800.1 confirmed by BLAST between the flanking sequence and the known sequence in the B. cinerea gene database. The mutant gene was identified as BC1G_02799.1 located in the upstream of BC1G_02800.1 gene by RTPCR. The DNA full-length sequence of BC1G_02799.1 was 1951 bp and contained 1848 bp coding region, which encoded a 615 amino acids putative protein similar to ABC-transporter, and the function of BC1G_02799.1 gene was unknown to date. Phenotype analysis of the mutant found that the mutant strain colony was white, grew slowly, and did not produce conidium and sclerotia on PDA medium but showed a stronger pathogenicity to tomato leaves and successfully increased the enzyme activity related to pathogenicity compared to the wild type strain. The results suggested that the BC1G_02799.1 gene was involved in the conidium development, the sclerotia formation, and pathogenicity in B. cinerea. Our research will facilitate in understanding the molecular mechanism of conidium development, sclerotia formation, and pathogenic in B. cinerea.     

Construction of RNAi vector for flower-related gene and verifications of the mutant in Arabidopsis thaliana

The timing of floral transition is tightly controlled by a combination of endogenous and environmental signals. One early flowering mutant plant was screened from Arabidopsis library of T-DNA insertion to accelerate flowering under short-day condition, and a related-gene EFS1 (AT4G36680.1) was isolated and identified as a novel flowering-time gene of Arabidopsis in our preliminary studies. To investigate the function and the specific mechanism of EFS1 in the flower process control, the RNAi expression vector containing EFS1 gene-specific sequences in the sense and antisense orientations was constructed and transferred into Arabidopsis by using the floral-dip method, with 11 transgenic plants obtained through hygromycin B screening and PCR assays. The results showed that the expression level of EFS1 in transgenic lines was significantly lower than that in wild type and efs1 mutant. The flowering time of the efs1 mutant and RNAi transgenic plants was much earlier than that of wild-type plants. This result further verified that the EFS1 gene played an important role in flowering, and its specific mechanisms need further study. These work provided a foundation to further regulatory mechanisms of EFS1 in the control of floral transition.     

Knockdown of ACS9 expression in Arabidopsis decreases the tolerance to salt and osmotic stress

Based on the DNA sequence of ACS9, two produced fragments were subcloned into binary vector pCAMBIA1300 in antisense and sense orientations, and the generated RNA interference (RNAi) vector was then transformed into Arabidopsis thaliana. The stress resistance function of ACS9 gene in Arabidopsis thaliana was researched by determination of stress resistance physiologic indexes, NaCl and PEG6000 resistance. The results showed that the inhibition of ACS9 expression enhanced the sensitivity to high concentration NaCl (150 mmol/L) and PEG6000 (7%) in Arabidopsis thaliana seeding stage. The proline contents and water loss rates in transgenic plants were 0.68 and 1.4 times higher than those in the wild-type leaves, respectively, indicating that the inhibition of ACS9 expression due to salt and drought resistant was reduced and suggested that ACS9 gene played important roles in plant salt and drought tolerance.     

Cloning and pharmaceutical analysis of CaMK gene of Botrytis cinerea

Using a PCR homology approach, DNA and cDNA sequences of calcium/calmodulin-dependent protein kinase (CaMK) gene of Botrytis cinerea were obtained. Southern blotting result displayed that CaMK was single copy in the genome of B. cinerea. The cDNA sequence of CaMK revealed an open reading frame of 2190 nucleotides encoding a 730 amino acid protein with predicted molecular weight of 81.8748 kDa. The genomic sequence of CaMK revealed the same ORF interrupted by six introns. Bioinformatics analysis showed that this protein had the distinctive features that characterize CaMK ATP binding region signature and serine/threonine protein kinase active-site signature. Pharmaceutical analysis displayed that the CaMK specific inhibitor, KN-62, could inhibit conidial germination, pathogenicity and herbicidal activity of B. cinerea BC4 strain. It was suggested that CaMK played an important role in regulating conidial germination, pathogenicity and herbicidal activity of B. cinerea.     

贵州省1984—2010年农区鼠情监测结果分析

为研究农区鼠类种群组成及种群数量变化规律,并为其种群数量预测预报和防治提供科学依据。通过分析1984—2010年贵州省30个县(市、区)农区鼠情监测结果表明,贵州省家栖鼠类和农田鼠类隶属2目(啮齿目、食虫目)3科(鼠科、仓鼠科、鼩鼱科)18种,主要集中于鼠科,占总种数的77.78%,在区系组成上以东洋界种类占绝对优势,占总种数的66.67%。褐家鼠、黄胸鼠为家栖鼠优势种,分别占总鼠数的51.26%、29.16%,小家鼠为常见种,占总鼠数的16.80%;黑线姬鼠为农田区(稻田、旱地)害鼠优势种,占总鼠数的62.57%,褐家鼠、黄胸鼠为常见种,分别占总鼠数的12.29%、14.73%,在部分地区为农田害鼠优势种,高山姬鼠为黔西北部分地区优势种。贵州省农区灭鼠的重点是黑线姬鼠、高山姬鼠、褐家鼠、黄胸鼠、小家鼠5种害鼠,应将其列为贵州省主要的监测对象。住宅区混合鼠种种群数量明显高于农田区,种群数量呈明显的下降趋势,不同年度、不同时期、不同月份、不同季节种群数量存在明显差异。根据贵州省多年来的农区鼠害测报及防治实践,明确了农区鼠害监测及综合防治的技术路线,提出了一套切实可行的农区鼠害监测技术和综合防治配套技术。     

三肽囊素与胸腺九肽对猪伪狂犬和猪口蹄疫疫苗免疫效果的影响

为研究人工合成的三肽囊素与胸腺九肽对伪狂犬和口蹄疫疫苗免疫效果的影响,选择40头体重相近的1月龄仔猪随机分为4组,接种伪狂犬疫苗1头份/头,同时,第I组注射10μg/kg的三肽囊素,第II组注射5μg/kg的胸腺九肽,第III组注射10μg/kg的三肽囊素和5μg/kg的胸腺九肽,第IV组注射等体积的生理盐水。1周后接种猪O型口蹄疫疫苗2头份/头,同时各试验组注射与前次等量的三肽囊素(10μg/kg)或胸腺九肽(5μg/kg),在伪狂犬疫苗注射后第1、2、3、4、6、7、8、9周采血,采用ELISA方法检测伪狂犬及口蹄疫抗体水平。研究结果表明,三肽囊素与胸腺九肽单独或联合应用均可提高伪狂犬及口蹄疫疫苗免疫后的抗体水平以及抗体的维持时间,说明三肽囊素与胸腺九肽可增强猪伪狂犬和口蹄疫疫苗的免疫效果。     

不同防寒措施对树莓生长和越冬的影响

通过大棚保温防寒、埋土防寒和露地越冬3种不同的防寒处理方式,研究了8个树莓品种的越冬情况,记录不同防寒措施下树莓的抽条率、成活率以及枝梢的生长量。结果显示:3种越冬处理下树莓的植株成活率均达到98%以上,表明树莓的各供试品种均能在本地安全越冬,但露地越冬的树莓发生较严重的抽条现象;树莓在大棚内越冬的萌芽时间最早,其次是埋土防寒的处理,最后是露地越冬的处理;同一品种树莓在大棚内越冬的植株长势强于埋土防寒和露地越冬防寒处理的树莓。     

基于发展类型理念的多功能人工林经营模式研究

现代森林经营已经从木材导向的单一经营向探索森林多功能可持续经营和实现预期林相技术的转变,但人多地少的林情和不同的功能需求亟待改变长期以来追求木材产量的经营理念,导向社会与生态效益的多功能人工林模式。文中基于发展类型多功能人工林经营理念,探讨了多功能人工林经营模式下的概念框架、目标内容,重点阐述了多功能人工林经营的林分作业法设计,以杉木和木麻黄人工林经营模式为典型应用案例解释了森林发展类型的发展目标、树种比例、混交类型、近期营林措施等设计理念,以期为多功能人工林经营设计提供一种有效可行的思路与技术参考。