Biological control of fruit flies in Hawaii: Factors affecting non-target risk analysis

The potential negative impacts of biological pest control on non-target species have become the focus of a contentious debate. In this article, we use examples from both classical and augmentative biological control of fruit fly pests in Hawaii to address several important factors in assessing non-target risks of fruit fly parasitoids. Several fruit fly parasitoids have been introduced to Hawaii and contribute substantially to the reduction of pest populations in the state's farms and forests. However, an historical lack of host-specificity testing of these parasitoids with non-target species has raised concerns about their impact on non-pest fruit flies, including some flies deliberately introduced for biological control of weeds and others that are endemic Hawaiian species. When developing protocols to assess risks of introduced fruit fly parasitoids, we need first to define an appropriate range of species against which host specificity should be tested. For assessing susceptibility of a non-target species to parasitoids, behavioral tests are as important as suitability tests. Experimental factors, such as host-exposure substrate, absence or presence of preferred hosts, and laboratory vs. natural conditions, are shown to affect the results of host-specificity tests and risk analysis. Still, assessing long-term, indirect ecological impacts of parasitoids and weighing potential risks and benefits in multiple dimensions (besides dollar values) remains a challenge to environmentalists, conservationists, applied ecologists, and biocontrol practitioners.     

诱剂监测四川果蔬实蝇种类发生与生态地理分布

报道了1997～2001年用Me、Cue、Tri三种实蝇信息素和水解蛋白在四川47县(市、区)341个点的田间诱捕监测实蝇的种类发生和地理分布的结果。监测结果表明，共收集到实蝇标本15277个，分属于离腹寡毛实蝇属(Bactrocera Macquart)的8个种和合腹寡毛实蝇属(Dacus Fabricius)属的1个种，其中发现新记录种2种。根据气候和地理条件等特点和实蝇区系种类组成，可将四川果蔬实蝇的生态地理分布分为5个类型，即盆地中亚热带地理分布区、盆地边缘北亚热带地理分布区、川西南山地南亚热带地理分布区、川西山原暖温带地理分布区和川西北高原寒温带地理分布区。川西南山地南亚热带地理分布区的实蝇种类最丰富，其次是盆地中亚热带生态地理分布区。在川西山原暖温带地理分布区和川西北高原寒温带地理分布区未发现有果蔬实蝇分布。     

鸡Myogenin基因单核苷酸多态检测及群体遗传分析

肌纤维在决定肌肉生长和肉质方面起主要作用,并受到MyoD基因家族的调控。该家族基因编码螺旋-环-螺旋蛋白。以鸡Myogenin基因为候选基因,通过PCR-SSCP分析该基因5′调控区的变异。结果表明,在鸡Myogenin基因5′调控区存在3处SNPs,这些SNPs产生的不同基因型及等位基因在7个品种鸡间分布存在极显著的差异(P<0.001)。推测该基因的变异对鸡生长发育可能有一定的影响。     

丽水山区单季稻病虫发生特点与防控措施

丽水山区单季稻应用品种繁多,主导品种不突出,生育期严重不齐,病虫发生复杂,为害严重,为减轻病虫危害,减少农药使用量,根据山区病虫发生特点,制定应对措施,取得很好的防控效果。     

一对单显性大豆抗疫霉根腐病基因的遗传分析及定位

[目的]大豆疫霉根腐病是大豆毁灭性的病害之一,防治该病最安全有效的方法是培育和利用抗性品种。迄今为止,已在大豆基因组上鉴定了21个大豆疫霉根腐病抗性基因,但是在中国只有少数基因(如Rps1c、Rps1k等)抗性有效。因此,急需发掘新的大豆疫霉根腐病抗性基因,以满足抗病育种的需要。‘大方六月早’对大豆疫霉菌的抗谱较广,是目前筛选出的优异抗源。[方法]采用下胚轴创伤接种方法进行抗病性鉴定,以品种‘大方六月早’为抗病亲本与品种‘矮脚早’配置杂交组合获得F2∶3代家系群体,并进行遗传分析,通过SSR(simple sequence repeat)标记对‘大方六月早’的抗性基因进行定位。[结果]该群体的抗性遗传分析表明:‘大方六月早’对大豆疫霉根腐病的抗性由1对主效基因控制,抗病对感病表现为显性,暂命名为RpsAH。使用SSR标记进行分子作图,抗病基因RpsAH被定位在大豆3号染色体(即N连锁群)上,距离标记Sat_166为4.1 cM。[结论]大豆品种‘大方六月早’对大豆疫霉菌株AH的抗性由1个单显性基因控制,该基因定位于大豆分子遗传图谱N连锁群上。     

Expression and properties of two types of protein kinase C: alternative splicing from a single gene

Two complementary DNA's, encoding the complete sequences of 671 and 673 amino acids for subspecies of rat brain protein kinase C, were expressed in COS 7 cells. The complementary DNA sequence analysis predicted that the two enzymes are derived from different ways of splicing and differ from each other only in the short ranges of their carboxyl-terminal regions. Both enzymes showed typical characteristics of protein kinase C that responded to Ca2+, phospholipid, and diacylglycerol. The enzymes showed practically identical physical and kinetic properties and were indistinguishable from one of the several subspecies of protein kinase C that occurs in rat brain but not in untransfected COS 7 cells. Partial analysis of the genomic structure confirmed that these two subspecies of protein kinase C resulted indeed from alternative splicing of a single gene.     

1个新的玉米半透明皱缩胚乳突变体的遗传分析及基因定位

【目的】解析半透明皱缩玉米胚乳形成机制.【方法】以纯合玉米突变体M-E-479为供试材料,通过对M-E-479籽粒进行表型鉴定、遗传分析、主要成分测定及扫描电镜观察,构建定位群体,利用图位克隆技术对突变基因进行遗传定位.【结果和结论】M-E-479突变体胚乳中脂肪含量增加,蛋白质和淀粉含量下降,淀粉粒的大小、形状、排列空间发生改变;用F2群体将突变基因定位在10号染色体SSR标记bnlg1074与umc1506之间,两标记的遗传距离约为3.6 cM,两标记的物理距离约为2.2 Mb.可见M-E-479是一个新的玉米半透明皱缩胚乳突变体,突变性状是由隐性单基因控制.     

FecB基因连锁微卫星在小尾寒羊中的多态性及其与产羔数的相关性

选用位于绵羊第6号染色体上与多羔基因FecB紧密连锁的微卫星座位LSCV043,300U和BMS2508,对32只小尾寒羊的多态性和产羔性状进行了研究,结果发现:3个微卫星座位在小尾寒羊中的等位基因数分别为11、8和10;3个微卫星座位的多态信息含量、遗传杂合度和有效等位基因数分别为0.851/0.878/7.39,0.822/0.853/6.24,0.858/0.885/7.75.LSCV043的基因型139 bp/115 bp对应的小尾寒羊产羔数最小二乘平均值最高,为3.67只/胎;300U的基因型172 bp/156 bp对应的最小二乘平均值最高,为4.00只/胎;BMS2508的基因型178bp/166 bp对应的最小二乘平均值最高,为4.00只/胎.     

Bacterial extracts and bioformulates as a promising control of fruit body rot and root rot in avocado cv. Hass

At least 20–40% of annual losses of avocado crops are caused by pathogenic fungi. The chemical treatments of these diseases are inefficient, cause environmental pollution and are increasingly restricted by international laws. This work aimed to assess the biocontrol capacity of a bacterial extract to protect avocado fruits and plants from pathogen infections. Extracts from the bacterial isolate Serratia sp. ARP5.1 were obtained from liquid fermentations in a biorreactor. A body rot postharvest infection model with Colletotrichum gloeosporioides on fruits was developed. Moreover, packaging conditions were simulated using the bacterial extract and the commercial fungicide prochloraz as a positive control. Additionally, seedlings infections with Phytophthora cinnamomi were performed on two types of avocado(West Indian race and cv. Hass). The Area Under Disease Progress Curve(AUDPC) was recorded using the bacterial extract and a commercial product with fosetyl-aluminium as treatments. The bacterial extract significantly reduced infections by C. gloeosporioides on injured avocado fruits at 31.1 μg mL–1. Intact fruits were also protected against body rot infections at the same concentration and showed no significant differences with the commercial fungicide. On the other hand, AUDPC in the seedlings was significantly reduced with the extract treatment at 3 μg mL–1 compared to the control. However, a possible phytotoxicity effect of the extract was evidenced in the seedlings and confirmed by pathogen recovery and tests on Raphanus sativus seedlings. Finally, formulations of the extracts(emulsion and emulsifiable concentrate) were prepared, and bioactive stability was assessed for 8 wk. The emulsion formulates demonstrated very stable bioactivity against P. cinnamomi. The extract and the emulsion formulate showed promising results for the control of avocado pathogens. New bioproducts based on this type of active principles could be developed for the benefit of avocado industry.     

一个籼稻叶夹角新基因的激素敏感性分析和基因定位

本研究对一个叶夹角变小、叶片短而直立的突变体ser(Short and erect)进行了植物激素敏感性试验和基因定位。激素试验结果表明,ser对赤霉素(Gibberellic acid,GA)敏感而对油菜素内酯(Brassinolide,BR)敏感性降低。遗传分析结果表明,ser的直立叶性状受1对隐性单基因ser控制。在ser×08CR578 F2群体中,利用分子标记将ser基因定位在水稻第5染色体长臂上的标记RM3437与RM5454之间,ser基因距离2个标记的遗传距离分别为5.3c M和1.5 c M;在ser×L604 F2群体中,ser基因定位于第5染色体上标记RM18504与RM1237之间,距离2个标记的遗传距离分别为1.5 c M和2.1 c M。在2个群体中,ser基因均与标记RM18532共分离。本研究为进一步精细定位与克隆ser基因奠定了基础,也为解析水稻叶夹角变化机制及选育高产理想株型水稻提供了理论支撑和基因资源。     

中华绒螯蟹取食褐飞虱与3种杂草的初步研究

在室内研究了中华绒螯蟹对 1种水稻害虫褐飞虱和 3种稻田杂草紫背萍、稗草、水莎草的取食作用。结果表明 ,中华绒螯蟹对褐飞虱的控制作用相当明显 ,且随着褐飞虱密度的增加 ,河蟹对它的取食量明显增加 ;河蟹对 3种稻田杂草的取食则存在明显的选择性 ,总的表现为对紫背萍和水莎草的取食能力强 ,对稗草的取食能力弱 ,且河蟹的取食能力随龄期的增长有下降的趋势     

甘蓝型油菜氮高效的生理与分子遗传基础研究进展

氮是植物生长发育所必需的大量营养元素。油菜对氮肥的需求量较大,氮肥利用率低。不同油菜品种的氮效率存在较大的基因型差异。与氮低效基因型油菜相比,氮高效基因型油菜在氮的吸收、转运、代谢、光合作用以及再利用等方面表现出显著的优势。同时,参与上述过程的基因包括硝酸根转运基因(NRT)、铵离子转运基因(AMT)、编码植物氮代谢相关酶类的基因以及其他基因等的表达水平也受到氮水平的显著影响,并在氮高、低效基因型间表现出显著的差异。本文主要从甘蓝型油菜氮效率的基因型差异、氮高效的生理与分子遗传基础等方面简要介绍了近年来关于甘蓝型油菜氮效率方面的研究进展。     

Phenotypic basis of reproductive success in a social insect: genetic and social determinants

Social insects live in societies that include both reproductive and nonreproductive adults. Understanding the factors that determine which individuals become successful reproductives is necessary to explain the evolution of these societies. The phenotypic effects of the gene Pgm-3 (or a closely linked gene) that may cause workers of the fire ant Solenopsis invicta to selectively execute all queens of a specific genotype were investigated. These effects, which involve differences in queen reproductive development, are expressed only in colonies exhibiting a particular type of social organization (multiple-queen colonies), and it is only in such colonies that selective execution on the basis of genotype occurs. This is an unusual example of genotype-environment interaction in gene expression in which the environmental component is the social environment. The queens executed are, surprisingly, those with the greatest reproductive development. Thus, there is a counterintuitive relation between the potential and realized reproductive success of queens in multiple-queen societies of this ant.     

Neurological defect: manganese in phenocopy and prevention of a genetic abnormality of inner ear

A specific congenital ataxia may be caused by presence of mutant genes and by manganese deficiency during prenatal development in normal mice. Supplementation of the diet of mutant mice with manganese during prenatal development rectifies the aberrant development, resulting in normal behavior. The congential ataxa results from defective development of the the otoliths.     

结缕草热激蛋白基因ZjHSP19.5植物表达载体构建及转化

以结缕草(Zoysia japonica Steud)cDNA为模板,利用PCR扩增ZjHSP19.5基因,并插入到PGEM-T Easy Vector上构建成克隆载体ZjHSP19.5-T。利用限制性内切酶BamHI分别对克隆载体ZjHSP19.5-T和植物表达载体PZH01进行单酶切,得到目的基因和线性质粒。在T4DNA连接酶的作用下将两者进行定向连接,经琼脂糖凝胶电泳检测、酶切鉴定,获得植物表达载体P-ZjHSP19.5。利用农杆菌介导法将重组植物表达载体P-ZjHSP19.5转化至匍匐翦股颖,为进一步研究ZjHSP19.5的功能和培育匍匐翦股颖抗热新品系打下基础。