棉花混选-混交育种体系遗传改良效应研究——Ⅰ.主要育种目标性状的响应

研究了陆地棉主要性状对混选—混交育种体系的响应。两轮群体提高了产量、早熟性和降低了麦克隆值的平均数;扩大了纤维品质的变幅;增加了高产株率,但对改进抗枯黄萎病性不明显。一轮群体的效果低于二轮。两次混交扩大了产量和纤维品质的变幅,增加了正末端的个体频率。一次混交的作用不及两次。早代混选相对缩小了群体变幅。一次混交后再经两代开放授粉和对一轮群体再混选,均表现出有益的反响。     

Artificial Insemination with Frozen Semen in Ewes at Different Times of the Breeding Season

Totally 13575 ewes of two different breeds, Dala and Spel, were inseminated with semen, frozen in straws and thawed at 70°C for 8 sec. An insemination dose of 0.2 ml containing approx. 150 × 10⁶ spermatozoa with at least 45 to 50% progressive motility was imerted 5 to 12 mm into the cervix. The insemination was performed once between 12 and 30 h after the onset of heat. The NR rate of the Dala ewes increased significantly during the season. The NR rate of the ewes inseminated before 15. November was 44.3%, from 15. to 20. November 52.2%. from 20. to 25. November 55.3% and from 25. November and later 61.4%. The corresponding values for the ewes of the Spel breed were 57.3, 58.7, 61.5 and 71.0% respectively, and only the difference between the two last values was statistically significant. The difference between the fertility of the two breeds was significant within each of the periods .     

香鱼人工育苗技术

根据作者多年来香鱼人工育苗的实践经验，总结了香鱼人工繁殖和苗种培育中关键性的技术。     

优良乡土树种观光木选育与栽培技术研究

观光木是木兰科单种属植物，是国家保护的珍稀濒危植物，是我国南方常绿阔叶林中的优势建群树种。以其树干通直、材质优良、速生、树形优美等特性而备受关注。我们在观光木科学引种栽培的基础上，对其生物生态学特性、繁育技术、营林配套技术进行了一系列基础性的研究工作，为全面选育和开发该树种奠定了良好的技术支撑。     

北疆苜蓿属植物繁育系统的研究

采用等位酶技术，对北疆苜蓿属植物种群的繁育系统进行了研究。结果表明，北疆苜蓿属植物种群为外繁育系统，黄花苜蓿、多变苜蓿、紫花苜蓿基因组成中杂合体过多，均保持较低的自交结实率。参试苜蓿属植物表现某种程度的内繁育衰退现象，地理或生殖隔离等因素可能是导致个别种群出现内繁育衰退现象的原因之一。对北疆苜蓿属遗传资源保护时，既要选择遗传基础丰富的种和种群以保持最多的遗传变异，还要注意选择具有不同等位的种群以保持原有的基因和基因频率。     

苹果梨的育种价值

该文指出,苹果梨综合性状优良,是很好的梨育种种质资源;以苹果梨及其后代为亲本已选育出30余个新品种,大大丰富了梨种质资源;苹果梨的大果、耐贮、小果心、抗寒等优良性状在后代品种中有较强的表现;以苹果梨与多倍体品种杂交后代为多倍体的比率较高。并展望了苹果梨在今后育种中的主要研究方向。     

Male-to-female aggression in cage-housed common pheasants (Phasianus colchicus) during the breeding season was not related to male plasma testosterone level

1. The aim of this study was to investigate if male-to-female aggression of common pheasants in the course of the breeding season was related to the concentration of plasma testosterone and/or other biochemical plasma indicators in male pheasants housed in breeding cages. The influence of season on the concentration of testosterone and biochemical indicators was also investigated.

2. Males were divided into non-aggressive and aggressive groups during the breeding season based on ethological evaluation. At the beginning, in the middle and at the end of the breeding season, a blood sample was taken from all males on the same day and the concentration of selected biochemical indicators and the total circulating testosterone in the plasma were determined.

3. Male-to-female aggression during the breeding season of pheasants was not influenced by the total plasma testosterone of males.

4. The concentration of total plasma testosterone in males decreased gradually during the breeding season.

5. Male-to-female aggression of pheasants did not have a significant effect on any of the assessed biochemical indicators.

6. The influence of the breeding season affected the activities of alanine aminotransferase and aspartate aminotransferase as well as the concentrations of glucose, magnesium, potassium and chloride in the blood plasma of cage-housed male pheasants.     

诱变选育西瓜染色体易位系的步骤及其杂交1代少籽组合的选配

用60Coγ射线辐照干种子诱变培育西瓜染色体易位系,并用其进行选配少籽杂交子1代研究,对克服三倍体无籽西瓜种子发芽率低、成苗率低、制种成本高、育苗技术较复杂的缺陷具有重要的意义;易位系杂交子1代西瓜保持了二倍体杂交1代的优良特性,减少了单瓜籽粒数,提高了果实可溶性固形物含量,从而提高了西瓜品质和商品价值。详细介绍了诱变选育西瓜易位系的步骤和技术、易位系的特征特性和优良的西瓜染色体易位杂交1代组合,并针对选育的科丰黑美人、红牡丹等易位系杂交1代分析阐述了染色体易位系杂交一代的优点和应用前景。     

高效微生物杀虫剂对蚊虫的杀灭作用

新疆阿勒泰北屯地区位于额尔齐斯河下游,夏季蚊虫泛滥,严重威胁当地人民的身体健康.本研究跟踪调查了各种水体的幼蚊滋生情况,确定了幼蚊发生的2个高峰期分别出现在5月下旬至6月上旬及6月下旬至7月上旬,同时确定了洪水型积水、排碱渠积水和漫灌林带积水是幼蚊高发的孳生地类型.采集并对蚊虫样品进行形态学鉴定,确定了该地区的优势蚊种为刺扰伊蚊Aedes vexans.用苏云金芽胞杆菌以色列亚种Bacillus thuringiensis subsp.israelensis(Bti)水剂对该蚊种进行了室内生测,其LC50和LC90分别为0.055和0.198 mg/L.分别选取3种高发孳生地的3处积水进行野外试验,发现48 h后该药剂对幼蚊的杀灭率均在96％以上,对大面积孳生地也有很好的杀灭作用.监测显示成蚊出现的高峰时间是每年的6月上旬至6月中旬及7月中旬至7月下旬.连续施药3年后,2013年的成蚊数量相比2011年时下降幅度超过50％.本研究对于北屯地区蚊虫的进一步控制以及Bti制剂在新疆的推广有重要的意义.     

Challenges facing arthropod biological control: identifying traits for genetic improvement of predators in protected crops

Biological control is an efficient pest control method but there are still limitations that are hindering its wider adoption. Genetic improvement of biological control agents (BCAs) can help to overcome these constraints, but the choice of key attributes for better performance that need to be selected is still an open question. Several characteristics have been suggested but the harsh reality is that selective breeding of BCAs has received a lot of attention but resulted in very little progress. Identifying the appropriate traits to be prioritized may be the first step to reverse this situation. In our opinion, the best way is to look at the factors limiting the performance of key BCAs, especially generalist predators (pesticide compatibility, prey‐density dependence, non‐suitable crops, and extreme environmental conditions), and according to these challenges, to choose the attributes that would allow BCAs to overcome those limitations. The benefits of selection for higher resistance to toxins, whether artificially applied (pesticides) or plant produced (plant defenses); increased fitness when feeding on non‐prey food (supplemented or plant‐derived); and better adaptation to extreme temperature and humidity are discussed. In conclusion, genetic improvement of BCAs can bring about new opportunities to biocontrol industry and users to enhance biocontrol resilience. © 2020 Society of Chemical Industry