Rind puncture resistance in maize: inheritance and relationship with resistance to pink stem borer attack

The main pest of maize in north‐western Spain is the pink stem borer, Sesamia nonagrioides, and stem lodging is one of the consequences of attack. Since rind puncture resistance is related to stem lodging resistance, the objectives of this work were to estimate the genetic effects involved in the inheritance of rind puncture resistance and to determine the phenotypic correlation coefficients between rind puncture resistance and pink stem borer damage. Six generations from the crosses ‘CM109’בEP31’ and ‘CM109’בEP42’ and a 10‐inbred line diallel were evaluated in Pontevedra, Spain, in 1995 and 1996. The inheritance of rind puncture resistance had two significant components, one additive and one dominant. Non‐allelic and genotype × environment interactions were not significant. Improvement for internode rind puncture resistance to increase stem strength and stalk lodging resistance could have some positive influence on resistance to pink stem borer. However, its use as an estimator of pink stem borer resistance cannot be generalized and so must be restricted to programmes that involve materials exhibiting physical resistance to pink stem borer attack.     

Differences in food composition between territorial and aggregative juvenile crimson sea bream Evynnis japonica

ABSTRACT:   Food composition, fork length and condition factor of juvenile crimson sea bream Evynnis japonica were examined for two behaviorally distinct types of fish inhabiting a nursery ground. Studies were carried out from March to September 1996 at Morode Cove, Ehime Prefecture, Japan. One type of fish is solitary and territorial and the other type is aggregative. The food compositions of the two types of fish were different. Solitary fish foraged mainly on Gammaridea and Caprellidea (benthic organisms), and Copepoda (planktonic organisms); while aggregative fish foraged mainly on Copepoda, Appendiculata and Cladocera (planktonic organisms). These findings suggest that when we study food composition of E. japonica , it is imperative to consider whether the samples used for the analyses are from solitary (territorial) fish. Solitary fish showed significantly greater fork length and condition factor than aggregative fish, suggesting that the former will have a greater fitness value than the latter.     

物理教学中研究性学习的探讨

文章结合物理学科的特点,提倡在物理教学中开展研究性学习,强调教师应指导学生适当选择研究性学习的内容,培养学生研究性学习的兴趣,进而提高学生的创新能力.     

茶多酚解酒作用的实验研究

本研究以乙醇致醉的酒醉小鼠为研究对象，观察了小鼠酒醉时的兴奋性、共济失调能力以及其乙醇半数致死量(LD50)；并以食用茶多酚后30min再以酒精灌胃的各项指标进行比较。结果显示：茶多酚能够有效抑制小鼠的兴奋性，降低其共济失调能力，提高其乙醇半数致死量。这表明茶多酚对实验性小鼠有显的解酒作用。     

呼和浩特地区秋季淡水蓝藻初报

蓝藻在植物界中的分类地位是最为低等和原始的,其分布范围极为广泛。近年来,蓝藻在渔业生产、生物固氮、环境保护和监测以及植物分类系统的研究中,表现出愈来愈重要的作用。作者自1981～1989年的秋季,在呼和浩特市地区选择了十几个采集点进行采集,初步对呼和浩特市地区秋季淡水蓝藻进行了系统的调查与分类研究,这项工作在内蒙古尚为空白。根据这项研究,呼和浩特市地区秋季淡水蓝藻共有3个目,4个科,17个属,26个种,其中有7个种作为存疑种,尚需进一步研究。     

食品级过氧化氢对染菌虾仁杀菌效果研究

就新型杀菌技术-过氧化氢杀菌在虾仁加工过程中的应用进行了初步探讨。结果表明:过氧化氢对虾仁的适宜作用条件为:有效过氧化氢浓度1·27g·L-1,作用时间为2min,浸泡液与样品的比例为2:1或浸没样品。过氧化氢溶液受温度影响较大,溶液于低温下放置,随放置时间的延长,有效过氧化氢浓度逐渐降低,操作过程宜在低温条件下进行。过氧化氢溶液处理后的样品宜进行适度的水洗处理,以便去除大量残留在虾仁表面的过氧化氢,同时可以阻止残留过氧化氢对虾仁有机质成分的进一步氧化。     

肉桂粉实病菌两型孢子的研究

肉桂粉实病病原菌的无性阶段是病菌生命的基础,通过室内外的调查研究发现,肉桂粉实病的病原菌是花生油盘孢菌[ElaeodemafloricolaKeis],该病菌的无性阶段,除有隔菌丝外,有两型孢子。孢子适宜温度24℃左右,相对湿度98%以上,节孢子形成先于分生孢子。所有孢子都能致病,引起病害多次而集中,造成肉桂生产巨大损失。     

学为主体教为主导重在创新能力提高

课堂教学是学校教育的中心，也是培养人才的关键一环。培养学生的主体精神是搞好课堂教学的重要手段，发挥教师的主导作用是搞好课堂教学的关键所在，创新能力的培养是提高课堂教学质量的落脚点。     

工蜂对卵和幼虫性别识别能力的观察与研究

本研究通过改变雄性卵与幼虫的孵化和哺育状态，观察工蜂对这些卵和幼虫的接受情况，探讨工蜂对卵和幼虫性别的识别能力。结果表明，工蜂对卵和大龄幼虫性别的识别能力较强，而对1-3日龄小幼虫的性别的识别能力较弱。