养蟹稻田稻飞虱发生规律研究

通过系统调查和大田普查相结合的方法，研究明确了养蟹稻田稻飞虱的发生规律。养蟹田和非养蟹田稻飞虱的发生期基本一致。由于螃蟹对稻飞虱的控制作用，养蟹稻田稻飞虱的发生量比不施药对照田明显偏低，一般发生年份，不用药防治，即可控制稻飞虱的为害。养蟹田稻飞虱的分布与距养殖沟的距离呈显著的正相关。距养殖沟越远，虫量越高，防治时应注意区别对待。     

杨细蛾发生期与发生量预测及防治技术的研究

该文研究了杨细蛾ＬｉｔｈｏｃｏｌｅｔｉｓｐｏｐｕｌｉｆｏｌｉｅｌａＴｒｉｅｔｓｃｈｋｅ在新疆阿勒泰地区河谷林的发生与环境的关系，并采用物侯法，有效积温法、历期推算法对该虫成虫、卵、幼虫的发生期进行预测，以成虫或卵为基数预测３龄幼虫发生量。提出了加强营林措施，保护天敌及使用４０％氧化乐果，８０％敌敌畏或用５０％杀螟硫磷，５０％倍硫磷乳油的稀释液防治幼虫，用敌马烟剂或使用７４１插管烟剂防治成虫等防治方法     

辽宁朝阳棉区棉铃虫发生规律及防治对策

朝阳县棉田棉铃虫1年发生2代，主害代为二、三代。通过对近年来棉铃虫发生情况调查分析，提出种植方式改变、外区域棉铃虫发生重、天敌种群数量减少、偏重药剂防治、轻视诱杀防治是棉铃虫加重发生的主要原因。在棉铃虫综合防治中强调运用应急防治和长期控制相结合的防治对策。     

席草螟发生规律研究初报

1991～1992年在小港农场进行了席草螟发生规律的研究,结果表明:席草螟在湖北省每年发生6代,以高龄幼虫在本田席草茎内越冬;全年以第二代多发,总为害率达24.1%～30.9%;该虫化蛹部位低,羽化孔平均高度为2.93±1.47cm;其蚁螟在茎外的寻游时间仅20～30min。     

Comparative oncology: The paradigmatic example of canine and human mast cell neoplasms

In humans, advanced mast cell (MC) neoplasms are rare malignancies with a poor prognosis. Only a few preclinical models are available, and current treatment options are limited. In dogs, MC neoplasms are the most frequent malignant skin tumours. Unlike low‐grade MC neoplasms, high‐grade MC disorders usually have a poor prognosis with short survival. In both species, neoplastic MCs display activating KIT mutations, which are considered to contribute to disease evolution. Therefore, tyrosine kinase inhibitors against KIT have been developed. Unfortunately, clinical responses are unpredictable and often transient, which remains a clinical challenge in both species. Therefore, current efforts focus on the development of new improved treatment strategies. The field of comparative oncology may assist in these efforts and accelerate human and canine research regarding diagnosis, prognostication, and novel therapies. In this article, we review the current status of comparative oncology approaches and perspectives in the field of MC neoplasms.     

夏季施氮、钾肥对高羊茅褐斑病的影响

在大田条件下,研究高羊茅施用氮、钾肥对夏季褐斑病发病的影响。结果表明,施钾水平的高低及氮、钾交互作用对褐斑病发病的影响不大。夏季增施氮肥减轻了褐班病发病的严重度,但是加快了病害流行速率,施氮越高,病害扩展速率越快,恢复速率越慢。     

蜀宣花牛无角新类群胴体不同部位肌内脂肪酸组成成分分析及结构研究

为明确蜀宣花牛无角新类群胴体不同部位肌内脂肪酸组分和结构情况,选择10头体重为324.79 kg±43.51 kg的7～8月龄健康无角公犊牛作为试验动物开展育肥试验,试验期300 d,屠宰后45 min内采集里脊、外脊、眼肉、上脑、辣椒条、米龙、大黄瓜条、小黄瓜条、臀肉、牛霖、胸肉、腹肉和腱子肉共13个部位的组织样本,...     

Characteristics and Inheritance of Seed-Ageing Induced Mutations in Lettuce (Lactuca sativa L.)

Mutations affecting qualitative traits were induced by seed ageing in lettuce. The mutant plants were isolated in the A₂ generation and included chlorophyll-deficient types (chlorotica, lutescens, chlorina-virescens, luteo and viridalbo maculate), and morphological variants (dwarf and narrow, thick and curly leaf types). The leaf mutants were found to be either partially or completely sterile. Segregation pattern of the mutants in A₃ generation showed that, except for the maculata types, all chlorophyll deficiencies and the dwarf mutant are controlled by single recessive nuclear genes. The genetic status of the leaf mutants was not clear, due to possible pleiotropic effect of the mutant genes in inducing gametophytic sterility. The maculata mutants exhibited sorting out of the normal and chlorophyll deficient regions during vegetative development and segregated for different degrees of chlorophyll deficiency in selfed progenies. The maculata mutants probably originated by plastome mutations induced by nuclear mutator genes.     

Somatic Embryogenesis in Maize and Comparison of Genetic Variability Induced by Gamma Radiation and Tissue Culture Techniques

Sixteen inbred lines and one hybrid of manse were tested for their capability of somatic embryogenesis, and fully developed plants could be regenerated, from ten inbred, lines. The highest frequency of plant regeneration was expressed in the inbred line CHI 31, and when this line was crossed with a recalcitrant, non-regenerating line, the F₁ and BC hybrids were regenerable. The results of reciprocal crosses demonstrated that dominant nuclear genes and cytoplasmic factors are primarily responsible for the heritable determination of embryogenic callus proliferation and in vitro regeneration of maize plants. Somaclonal and radiation-induced variability was studied in maize to assess their nature and potential contribution to plant breeding., The inbred line CHI 31 possessing a high in vitro capacity of somatic embryo formation was used as experiments.] material. CHI 31 plants were selfed and twelve-day old zygotic embryos irradiated with ⁶⁰Co gamma radiation in situ. Mature caryopses were harvested and assigned as M₁ material. In another series, immature zygotic embryos (size 1.2—1.5 mm) were cultured in vitro on N-6 medium supplemented with 2,4-D (2.5 μM), and somatic embryos regenerated into plants; these were transplanted into soil and self-pollinated. Regenerants from non-irradiated cultures were grown as R₁ generation, while regenerants from irradiated explants were considered as M₁R₁ generation. The genetic variability was evaluated in the M₂, R₂ and M₂R₂ generations, respectively, and compared with a non-treated seed control. Irradiation induced a variety of chlorophyll and morphological variants segregating in the M; generation; however, the frequency of deviant types obtained in the R: generation (somaclonal variation) was significantly exceeding the one derived from the M₂ populations. The combination of expert irradiation and in vitro regeneration was most effective for the manifestation of chlorophyll and morphological o if types in the M₂R₂ generation, and increased drastically the frequency of early flowering variants. Differences in the segregation patterns of mutant phenotypes amonsister somaclones in the R₃ and M₃R₃ generations indicate a different genetic basis, of plants originating from the same explant. This phenomenon suggests a mutational sectoring of the callus during culture. Radiation induced and somaclonal variation exerted a similar spectrum of chlorophyll and morphological deviants.     

Efforts to chemically induce mutations for cytoplasmic male sterility in petunia. I. Field experiments

Summary In the period 1980–1984 about 70000 selfed seeds of the petunia cultivar Blue Bedder were treated with the chemical mutagens ethidium bromide (EB) and ethylnitroso urea (ENU) with the intention to induce (new sources of) cytoplasmic male sterility (CMS). This work resulted in 27 stable male sterile MS-plants, all derived from the ENU-treatments.Crosses with the normal fertile type and with material carrying restorer genes for the common type of CMS in petunia were made. Results obtained from some MS-plants raise a presumption of genic male sterility, probably of the dominant type, having been induced. More detailed investigations are underway.