Enriched production of N-hydroxycinnamic acid amides and biogenic amines in pepper (Capsicum annuum) flowers

The biosynthesis of N-hydroxycinnamic acid amides (HCAAs), such as feruloyltyramine, p-coumaroyltyramine, feruloylserotonin, and p-coumaroylserotonin, in pepper plants was investigated in view of the activity of their corresponding enzymes and substrate levels. Almost all HCAAs were found in flowers, whereas the enzyme activity essential for HCAA biosynthesis seemed to be expressed constitutively in all tissues tested. The highest levels of the biogenic amines tyramine and serotonin, the key amine substrates, were also found in flowers, indirectly suggesting that the amine substrates play an important regulatory role in the synthesis of HCAAs.     

Exogenous carbon monoxide protects against the lung injury induced by ischemia-reperfusion of hind limbs in rats

AIM: To study the mechanism of protective effect of exogenous carbon monoxide (CO) in the lung injury induced by ischemia-reperfusion (IR) of hind limbs in rats. METHODS: Thirty-two SD rats were randomly divided into 4 groups: control, control+CO, IR and IR+CO. A rat model of ischemia in hind limbs and the reperfusion lung injury was made. The rats in IR+CO and control+CO groups were exposed to air containing 2.5×10-8 CO for 1 h before reperfusion or the corresponding control time point, while the other two groups were exposed to the routine air. The lung tissue structure, polymorphonuclear leukocyte (PMN) count, wet-to-dry weight ratio (W/D), malondialdehyde (MDA) content and the animal survival rate were observed. The carboxyhemoglobin (COHb) levels in artery blood were detected with CO-oximeter and the expression of intercellular adhesion molecule-1 (ICAM-1) in the lung was detected by Western blotting. RESULTS: Compared to control, the animal mortality, lung PMNs number, W/D, MDA content and ICAM-1 expression were all significantly increased in IR group. Compared with the IR group, the blood COHb level was significantly increased and the animal mortality, lung PMNs number, W/D, MDA content and ICAM-1 expression were all significantly decreased in IR+CO group. CONCLUSION: These data suggest that exogenous CO attenuate limb IR-induced lung injury by down-regulatiny ICAM-1 expression and suppressing PMN sequestration in the lung following limb IR in rats.     

采后热空气处理对金冠苹果后熟衰老及病害的影响

金冠苹果采用38℃,72h或96h热空气处理,可降低0℃贮藏中果实的呼吸强度和乙烯释放量,延缓非溶性果胶的降解,维持较高的硬度、脆度,同时也会加速果皮的褪绿变黄和固酸比的上升,尤其是38℃96h处理的作用效果更为明显,显著提高了货架期后(20℃7d)苹果的质地品质和可接受程度,延缓衰老。苹果分别接种扩展青霉、灰葡萄孢霉,0℃和20℃条件下其病害发生率和腐烂均很严重,采用38℃96h热空气处理可以完全控制病害的发生,避免腐烂。可见,热空气处理一方面能延缓金冠苹果的后熟衰老,另一方面还能控制贮期病害的发生。     

新型植物激素与蔬菜作物抗逆性关系研究进展

综述了近年来水杨酸、茉莉酸类化合物、油菜素内酯、多胺和5-氨基乙酰丙酸等新型植物激素与蔬菜作物抗逆性关系的研究进展,从盐胁迫、低温胁迫、高温胁迫、低氧胁迫、病害胁迫、虫害胁迫等方面阐述和分析了新型植物激素与蔬菜作物抗逆性的相关性,并指出相关研究的有待深入之处。     

沙棘植物柔性坝坝体变形初步分析

本文基于2005年在内蒙古准格尔旗西召沟小流域对已植的沙棘柔性坝进行野外调查,从植物生长角度对沙棘柔性坝坝体进行了纵向、横向、垂向(即沙棘柔性坝坝长、坝宽、坝高)的变形分析。对于沙棘柔性坝的坝长变化,主要从沙棘根系蘖苗萌生出发,分析得出其每年扩展约1m;柔性坝坝宽受沟宽限制,其发展趋势为扩展至满沟;柔性坝坝高变化采用三次函数和Logistic型函数两种具有“S”形特征的曲线进行拟合分析,经对比其变化过程服从Logistic型生长函数,并结合Logistic函数对沙棘植物柔性坝坝高的变化进行了具体意义的探讨。     

杂交稻对稻瘟病和稻白叶枯病的抗性鉴定

对广东省将推广的54份杂交稻组合对稻瘟病和白叶枯病的抗病性进行了鉴定。对稻瘟病的抗病性鉴定表明:抗病组合共49个,占90.7%;其中,高抗(抗性比≥91%)组合30个,占55.6%。对稻白叶枯病的抗病性鉴定表明:没有高抗(HR)和抗(R)的组合,仅有一个杂交稻组合(西胜2175)表现为中抗(mR),仅占1.9%,其余53个组合都表现感病,占98.1%。进一步分析表明:对稻瘟病表现高抗的30个杂交稻组合都不抗白叶枯病,而中抗白叶枯病的杂交稻组合西胜2175对稻瘟病表现为中抗,抗性比为74%。     

微卫星DNA标记及其在检疫性实蝇种群遗传学中的研究应用

微卫星DNA是一种广泛用于种群遗传学研究的分子标记技术,具有共显性标记、反应速度快、重复性好和结果可靠等特点。本文在概述微卫星标记的原理、特点、位点筛选和引物设计的基础上,系统分析了该技术在检疫性实蝇(小条实蝇属、果实蝇属等)种群遗传关系中的研究与应用。     

牡丹上的一种新病害——牡丹瘤点病

介绍了牡丹瘤点病的症状,病菌经PDA培养基培养,进行病原菌鉴定,引起该病发生的病原菌为瘤座孢菌(Tubercularia sp.)。     

鸡β-防御素及其应用前景

防御素是生物界广泛存在的一类具微生物抗性的低分子肽，由于其抗菌谱最广，具有很高的应用潜力。本文概述了鸡β-防御素的分子结构、抗菌活性、基因表达调控的研究进展，并展望了其在畜牧业中的应用前景。     

塔里木盆地沙漠化防治措施及其效益

土地沙漠化是干旱,半干旱地区普遍存在的一个重大环境问题。塔里木盆地是我国沙漠化危害最严重的地区之一,但干旱多风的自然条件引起的沙漠化,仅占现代沙漠化面积的１５．１３％,说明沙漠化土地是可以治理的,本文概述了农田林网,林网内农林复合经营,防沙林带,灌草带,造林固沙等沙漠化防治措施及其效果。