稻文化的再思考(5):稻与粮政——改革开放后

在前文介绍我国古代到改革开放前的稻与粮政的基础上,本文概要介绍和分析了我国改革开放以后稻与粮政的关系。改革开放后,国家对粮食管理经历了计划和逐步放开管理到粮食市场化和宏观调控的转变,具体可分为三个时期:1979年开始的粮食统购统销的改变和1982-1986年5个"一号文件"带来粮食生产的快速发展时期;1994年工业化发展农业滑坡后国家的再次重视和控制时期;2004年开始的粮食宏观调控和放开市场及补贴发展时期。     

Homology of DNA sequences encompassing malignant hyperthermia mutation site in the ovine (Ovis aries) and porcine (Sus scrofa) ryr1 gene

The PCR products of ryr1 gene amplified from genomic DNA of Sus scrofa and synthetic prolific lines of Ovis aries were analysed. The polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP), and sequencing analysis for research on ovine, ryanodine receptor ( ryr1 ) gene. The ovine fragment of ryr1 gene did not differ from exon 17 of the porcine ryr1 gene.     

Restriction fragment length polymorphisms in myogenin and myf3 genes and their influence on lean meat content in pigs

A total of 120 pigs from farm I and 109 from farm II were examined for Dde I polymorphism in myf3 and for Msp I polymorphism in myogenin genes. Meatness, weight and ratio of ham and loin meat, and loin eye area of animals with different genotypes for myf3 and for myogenin were compared. In myf3 polymorphism pigs A/A from farm I displayed significantly lower values for these characteristics. In farm II there was a reverse tendency. Present results indicate that the Dde I polymorphic region in porcine myf3 gene does not influence functionality of this gene but it may point at another polymorphism located nearby and being of functional importance. Two regions of the porcine myogenin gene were analysed for Msp I polymorphism. The region encompassing coding sequences ( MYOG1 ) was polymorphic only in three Pietrain pigs (out of 150 individuals tested) making it useless for assessment of meat productivity in pigs. The 3' untranslated region was polymorphic and the frequency of 4.2 and 4.9 alleles varied among breeds. The 4.2 variant was predominant in Pietrain pigs. Statistical analysis indicated that meat, ham and loin meat percentages as well as loin eye area were significantly higher in 4.2/4.2 homozygotes. Further study will be undertaken to explain the relations between meat productivity and myf3 and MYOG2 alleles within breed.     

华北落叶松鞘蛾性信息素应用技术研究

1999年至2000年,山西省太岳山林局应用人工合成的华北落叶松鞘蛾性信息素对华北落叶松鞘蛾进行了监测,并开展了大量诱杀试验。结果表明,该引诱剂对华北落叶松鞘蛾雄蛾有较强的引诱作用,60个诱捕器在成虫扬飞期共诱到鞘蛾成虫51万头,应用诱捕器后,林地内华北落叶松鞘蛾被害率下降50.1％,虫口密度下降81.2％。可用于对华北落叶松鞘蛾的监测和防治。     

杉木优良无性系柳327组培不定根诱导

以杉木（Cunninghamia lanceolata）优良无性系柳327组培继代芽为材料,进行不定根诱导试验,结果表明,IBA对柳327无性系不定根诱导起主导作用,基本培养基起次要作用.将培养了35天,高2.5 ～4 cm的壮芽,扦插于1/2改良ER ＋2 mg/LIBA ＋2 mg/LIAA ＋VC 20 mg/L培养基,培养20天,生根率达97.1％.