滨旋花和兴安天门冬种子萌发特性的研究

从温度、pH值、盐分及混播方面对滨旋花和兴安天门冬种子萌发特性进行了研究。结果表明，滨旋花种子萌发的适宜温度为15～2．3℃，最适温度为20℃；而兴安天门冬种子萌发的适宜温度为23-28℃，其中25℃时发芽率最高；二者的种子适合在稍偏碱性环境下萌发；盐分对种子的萌发有抑制作用。滨旋花种子硬实率高，属于环境强迫休眠，人工处理种皮，可以解除休眠。     

Towards the management of field bindweed (Convolvulus arvensis) and hedge bindweed (Calystegia sepium) with fungal pathogens and cover crops

The bindweeds Calystegia sepium and Convolvulus arvensis aredifficult to control chemically. Calystegia sepium is often aproblem in maize or in vineyards, while C. arvensis is animportant weed of cereals. The biological control of these weedswith insects or fungal pathogens has been investigated since1970. More than 600 fungi collected in countries throughoutEurope have been isolated in our laboratories. The isolates withthe highest and most stable pathogenicity against bindweed belongto the genus Stagonospora. In a field trial in maize in 1995, oneof these Stagonospora isolates stopped the increase of groundcoverage by the bindweeds. In response to public concern aboutenvironmental problems caused by modern agriculture, new croppingsystems are being developed. Underseeding maize with a livinggreen cover achieves good control of a large spectrum of the weedflora typical of conventional tillage systems. However, C. sepiumand C. arvensis remain as problems. The research reported showsthat C. sepium is partly suppressed by the green cover, butescapes control by climbing the stems of the maize plants.Therefore, the application of spores of Stagonospora sp. in amaize field underseeded with a living green cover may allow alarge or a complete reduction of the herbicide input and promotea more sustainable agriculture     

田旋花对草甘膦的耐药性机制

在温室条件下,测定了草甘膦对田旋花与打碗花生长的抑制作用及其体内莽草酸含量变化的影响,比较了两者5-烯醇丙酮莽草酸-3-磷酸合成酶（5-enolpyruvylshikimate-3-phosphate syn-thase,EPSPS）基因及编码氨基酸的差异,以探讨田旋花对草甘膦的耐药性机制。结果表明,田旋花对草甘膦的耐药性较高,GR50值（有效成分）为2834.04g/hm2;打碗花相对敏感,GR50值为210.63 g/hm2。经有效成分922.50 g/hm2草甘膦处理后,耐药性高的田旋花体内莽草酸积累缓慢,处理后7天达到峰值,为397.69μg/g;而打碗花体内莽草酸含量呈现持续快速升高的趋势,处理后13天达到峰值,为1 299.52μg/g。克隆获得的田旋花和打碗花编码EPSPS cDNA长度相同,均为1 707 bp,编码520个氨基酸,两者在EPSPS保守区内存在不同的氨基酸位点,田旋花的第101位为极性丝氨酸,而打碗花为非极性苯丙氨酸。     

野生植物肾叶打碗花的生长特性及观赏价值

通过对秦皇岛市滨海地区野生盐生植物肾叶打碗花进行调查与分析,初步探索了肾叶打碗花的生长特性和经济价值,阐述了肾叶打碗花在园林绿化中的观赏应用价值,认为其在园林观赏方面具有很大的开发应用前景,并提出了在滨海地区园林应用上的建议.     

肾叶打碗花营养器官解剖学研究

采用石蜡切片法对青岛海滨地区的肾叶打碗花(Calystegia soldanella)营养器官解剖学特征进行了观察研究,结果显示: 肾叶打碗花为典型的泌盐植物;叶片上下表皮分布有由多细胞组成的盐腺;叶表皮细胞排列紧密,表皮外被有角质层;上下表皮都有气孔,气孔与表皮细胞基本齐平;为异面叶,有发达的栅栏组织.茎表皮上分布有气孔,与表皮细胞齐平;表皮与皮层之间有数层体积较小的厚壁细胞;薄壁细胞内有分泌腔分布;根表皮细胞向外突出形成大量根毛等.研究结果表明,肾叶打碗花的解剖结构表现出与其生境相适应的特征.     

沙生植物滨旋花种子特性及萌发研究

滨旋花是一种兼有观赏价值、药用价值、生态保护作用的滨海沙生植物。笔者对滨旋花种子形态特征、休眠特性和解除种子休眠的方法进行研究。结果表明：滨旋花种子黑色,卵圆形,为大型种子,质地坚硬。扫描电镜观察,滨旋花种皮表面具有不规则的六边形网格纹饰,网壁和网眼非常致密。未经处理种子吸水率很低,不能发芽,低温层积不能打破休眠。98%的浓硫酸处理60 min发芽率达94.9%;开水烫种发芽率达50%;混细沙研磨发芽率达81.8%,发芽最为迅速。由此可见,滨旋花种子休眠是由于种皮透性差造成的,改善种皮的通透性可以解除休眠,浓硫酸处理效果最好,混细沙研磨是环保型有效方法。     

Rhizome dynamics in Calystegia japonica Choisy and Calystegia hederacea Wall. in relation to overwintering

Calystegia japonica Choisy and Calystegia hederacea Wall., common perennial weeds throughout cropped and uncropped land in Japan, are known to regenerate mostly by rhizomes. The rhizome dynamics of the two species were investigated, focusing on their overwintering characteristics. The dry weight of rhizomes continued to increase for 6–7 weeks after the decrease in weight of the aerial parts began, then it decreased in winter because of the partial death and consequent fragmentation of the rhizomes. Overwintering as naturally fragmented rhizomes is a unique characteristic of the two Calystegia spp. as it is not observed in other rhizomatous weeds that maintain systematic connections at least during the following regeneration in spring. In C. japonica , rhizome degradation was more pronounced and more systematic than in C. hederacea , where thicker fragments that included apices remained. Qualitative changes in C. japonica rhizomes, such as increases in dry matter accumulation and starch, and a temporary decrease in sprouting ability, seem to relate to this specialized survival mechanism. Calystegia hederacea did not show either specialization or preparation for overwintering in its rhizome. The adaptability of Calystegia weeds to annual crop fields can be attributed to their capacity to regenerate from naturally fragmented rhizomes.