大白菜软腐病菌游动性突变体在大白菜体内增殖扩展研究

 用培养皿滤纸吸附测定法和不伤根土壤拌菌处理及针刺接种法,测定了大白菜软腐病菌游动性突变体进入大白菜体内、并在其中侵染定殖和扩展的特性。结果表明,游动性丧失和增强的突变体都可以通过种子萌发和主动接触进入大白菜体内、并可以在体内有短期的繁殖,但菌量远低于野生菌。大白菜叶片接种实验说明,这两种突变体也都可以进行短距离扩展,但扩展距离和菌的繁殖量低于野生菌。     

氮磷钾混合肥对锥栗坚果产量和质量的影响

以 5年生锥栗为试树 ,进行土壤穴施氮磷钾混合肥试验 ,研究不同氮磷钾肥配比对锥栗坚果产量和质量的影响。结果表明 ,不同组合处理之间 ,除叶片的蛋白质含量和单株果枝数有显著差异外 ,叶绿素含量、单枝结棚数、单株结棚数、栗棚重、坚果重、出实率、单株棚产量和坚果产量的差异均不大。以穴施 0 .2 0kg尿素、0 .1 0kg钙镁磷和 0 .1 5kg氯化钾的混合肥较经济而有效     

‘新红星’苹果果实蔗糖合酶的活性及亚细胞定位

 在‘新红星’苹果果实发育过程中, 伴随果糖、葡萄糖和蔗糖的积累, 蔗糖合酶的分解活性逐渐下降, 而合成活性逐渐升高。苹果果实的蔗糖合酶由分子量为90 kD 的亚基组成, 其免疫信号强度随发育进程而增加。蔗糖合酶主要定位于果肉细胞的细胞质中, 发育中后期该酶的分布密度有一定增加。综合结果认为, 蔗糖合酶调控发育早期蔗糖的降解和发育后期蔗糖的积累。     

苹果低氧气调新组合贮后效应的利用研究

利用0.12mm聚乙烯薄膜大帐进行低氧气调新组合的较大规模应用试验,对2394kg玫瑰红苹果进行低氧处理,帐内O2浓度可下调至约2%,CO2浓度可自动维持在5%～8%的较理想状态,处理结束后很易转为MA自发气调。低氧处理后再MA贮藏的苹果,虎皮病果率低、症状轻,腐烂果少,果柄和果皮新鲜,叶绿素保持效果好,果肉硬度明显高于小包装气调和冷藏对照。说明利用塑膜大帐进行前期低氧新组合处理与后期自发气调、实现低氧气调新组合贮后效应的利用是可行的。     

Effect of protein kinase C on the expression of myocardial HSP70 mRNA during myocardic ischemic preconditioning in rabbits

AIM:To study the relationship between myocardial HSP70 and PKC during myocardial ischemic preconditioning(IPC). METHODS: PKC inhibitor, polymyxin B(PMB) and PKC activator, phorbol 12-myristate 13-acetate(PMA) were applied to the models of myocardial ischemia/reperfusion in vivo and in vitro in rabbits, respectively, and the ventricular functions, PLA₂ in the serum, and the expression of mycardial HSP70 mRNA were examined. RESULTS:IPC decreased PLA₂ activity, improved the left ventricular function and increased the expression of myocardial HSP70 mRNA. Howerer, all these effects of IPC could be blocked by PMB. Interestingly, PMA mimicked IPC with attenuating the injuries of cardial myocytes and increasing myocardial HSP70 mRNA expression. CONCLUSION:PKC is involved in the myocardial HSP70 expression in case of ischemic preconditioning.     

Effects of external counterpulsation on renin-angiotensin system and hemodynamics in dogs with myocardial ischemia

AIM:To examine the effect of external counterpulsation(ECP) on renin-angiotensin system(RAS) and hemodynamics in dogs with myocardial ischemia and their relationship. METHODS:Acute myocardial ischemia was induced by occluding the left anterior descending of the dogs. The local renin activity, angiotensin Ⅱ(AngⅡ) level, angiotension-converting enzyme(ACE) activity were tested by biochemical methods and hemodynamics was recorded by a 8-channel physiological recorder.RESULTS:Ischemia could actiivate renin,ACE and AngⅡ in cardiovasculature and ECP reduced them except for renin in ischemic myocardium. Ischemia also could activate RAS in lung and kidney, which play an important role on circulating RAS, and ECP reduced them. Furthermore, ECP could improve hemodynamics and there existed a close relationship between local AngⅡlevel and hemodynamics. CONCLUSION:ECP can reduce local RAS and improve hemodynamics in dogs with myocardial ischemia, which might be one of mechanisms underlying the protective effect of ECP on ischemic myocardium.     

冬虫夏草的研究概况

冬虫夏草是一种十分重要的药用真菌，具有广阔的开发前景。本文介绍了冬虫夏草的生物学习性、化学成分、药理作用及人工培育现状，并展望了冬虫夏草研究的前提。     

黑杨萎蔫枝叶对棉铃虫生殖行为的影响

研究了黑杨(Populus nigra)萎蔫枝叶及其气味对棉铃虫成虫的隐藏部位、产卵部位、交配率及产卵量等的影响，并对黑杨萎蔫枝把在田间诱集到的棉铃虫雌蛾进行了解剖观察。结果表明，在田间，黑杨萎蔫枝把诱集到的棉铃虫93．3％已经交配。在气候箱中，放置黑杨萎蔫枝叶的环境中配对饲养的棉铃虫，经过1个暗期和2个暗期后，其交配率与对照环境中的均无显著差异。在光期开始时，有51．5％的成虫隐藏在饲养笼内所设置的黑杨叶子圆片下，对照纱布圆片下仅有16．7％。叶子圆片所在区域的日平均落卵量显著大于对照区。黑杨萎蔫枝叶及其气味对棉铃虫的产卵前期、产卵持续期、成虫寿命和产下50％的卵所用的时间无显著影响，但饲养笼内有黑杨枝把或黑杨叶片气味存在时，棉铃虫的产卵量比模拟枝把和对照显著提高。     

粉红女士苹果品质特性分析评价

观察测定了粉红女士苹果成熟采收时和常温贮藏后果实的外观、抗性、果实硬度、总酸、可溶性固形物、维生素C、蒸腾失水率、出汁率、果汁密度以及果汁性状;全面分析评价了该品种的外在、内在、贮藏品质和果汁加工特性。结果表明,粉红女士苹果是一个综合性状优良、耐贮藏的鲜食、果汁加工兼用型苹果新品种。     

荔枝环剥时期对新梢生长及碳素储备的影响

 枝梢环剥显著抑制了‘怀枝’荔枝新梢的生长，并导致射线细胞和髓部大量积累淀粉。梢芽萌发或伸长前环剥可完全抑制新梢生长，而新梢快速伸长期环剥对其抑制效应最弱。秋季环剥对新梢的抑制和对淀粉积累的促进效应明显高于春季环剥。环剥口以上的老叶面积和环剥位置并不影响环剥对新梢生长的抑制效应和促进淀粉的积累效应，但环剥口以上单位枝梢长度的叶面积与淀粉含量呈显著正相关。