四川凤仙花属(Impatiens)植物资源及新分布记录种

通过野外调查,国内主要标本馆及相关文献资料查阅,报道四川凤仙花属(Impatiens)植物80种1变种,其中20种为四川特产,17种为四川新分布记录种.列出新记录种的标本引证、地理分布,对丰富四川植物区系及四川凤仙花植物的物种多样性的研究具有重要意义.     

Effect of Excessive Calcium Applications on Growth and Postharvest Performance of Bedding-plant Impatiens

ABSTRACT

Application of excessive amounts of calcium (Ca) during the production cycle improves the quality and postharvest life of several florist crops. Most bedding plants are fertigated with Ca at 100 to 200 mg L^{? 1}throughout the production cycle, but we do not know the effects of higher Ca concentrations. The objective was to evaluate the effect of application of excessive Ca (≥ 280 mg L^?1) supplied during the production cycle on the growth, development, and subsequent postharvest performance of bedding-plant impatiens (Impatiens wallerana Hook. f. ‘Super Elfin White’) under simulated retail conditions. Calcium was applied at 120, 200, 280, 360, and 440 mg L^?1 during each fertigation during the growing cycle. The total nitrogen (N) concentration was 150 mg L^?1, and the nitrate (NO₃ ^?)-N to ammonium (NH₄ ⁺)-N ratio was 1:1. Application of excessive Ca began 30 d after sowing (22 d after germination) and continued until 60 d after sowing. From day 60 to day 65 only deionized water, as a leach, was applied. From day 65 to day 90, plants were held under shade cloth and irrigated with tap water. Excessive Ca applied during the production cycle decreased shoot dry weight, shoot fresh weight, leaf number, and shoot tissue K concentration at the end of the production cycle. Excessive Ca applied during the production cycle also decreased shoot dry weight, leaf number, and shoot tissue potassium (K) concentration at the end of the postharvest period. Plant height, plant diameter, number of open flowers, and number of unopened flower buds at the end of the production cycle and at the end of the postharvest period were not affected by the amount of Ca applied during the production cycle. It was concluded that excessive Ca applied to bedding-plant impatiens during the production cycle did not benefit plant performance during either the production cycle or the postharvest period.     

海南俄贤岭石灰岩山地海南凤仙花所在群落植物区系及生态特征

通过样方调查对海南俄贤岭石灰岩山地海南凤仙花Impatiens hainanensis所在群落的植物区系及生态特征进行了分析.结果表明,在总面积为800 m2的样地中,共记录了维管植物46科76属83种(含种下单位),以兰科(16种)、水龙骨科(5种)和大戟科(4种)等为优势.属的区系成分以泛热带分布(18属)和热带亚洲(印度-马来西亚)分布(15属)为主.群落以灌木层(29种)和草本层(45种)为主,灌木层以海南大戟Euphorbia hainanensis为优势,草本层以玫瑰毛兰Eria rosea占优势;藤本层植物9种,以眼树莲Dischidia chinensis为优势.生活型以矮高位芽(57种)为主.频度等级分布规律为A>B>D>C>E,属于A级的种类最多,有41种,其中草本层20种.与相同生境的海南大戟灌丛群落进行了比较,并对其有效保护提出了初步建议.     

新几内亚凤仙在宁夏地区的工厂化栽培技术

介绍了新几内亚凤仙育苗技术和苗木栽培技术。     

First release of a fungal classical biocontrol agent against an invasive alien weed in Europe: biology of the rust,Puccinia komarovii var. glanduliferae

The rust fungus Puccinia komarovii var. glanduliferae was first identified infecting Impatiens glandulifera in its native range (western Himalayas) between 2006 and 2010. Subsequently, it was imported into quarantine in the UK for evaluation as a classical biocontrol agent. To assess the safety of the rust, plant species relevant to Europe were tested for susceptibility. To confirm the life cycle, all infective spore stages were inoculated on I. glandulifera to follow disease progression. Teliospores were primed using bleaching and low temperatures to break dormancy. Temperature and dew period experiments using urediniospores were conducted to assess the parameters required for infection. Of the 74 plant species tested, only I. balsamina, an ornamental species, was fully susceptible to urediniospore inoculum. The life cycle of the rust – an autoecious, full‐cycled species with five spore stages – was confirmed. Urediniospores were infective between 5 and 25°C, with an optimum at 15°C. A minimum of 8 h dew period was required to achieve consistent infection. Based on a pest risk assessment, the rust poses no threat to native biodiversity within EU Member States; making P. komarovii var. glanduliferae a suitable candidate as the first fungal classical biocontrol agent against an exotic weed in the region.     

新几内亚凤仙凋萎病病原鉴定初报

 报道了新几内亚凤仙上的一种新病害——新几内亚凤仙凋萎病,是由立枯丝核菌(Rhizoctonia solani Kühn)为害所致。病菌适宜生长温度25～30 ℃.人工接种尚可侵染凤仙花、甜菜和辣椒。     

遮阴对凤仙花生长和开花的影响1）

以凤仙花为试验材料,研究了一层遮阴（遮光度为45％,简称S45）、二层遮阴（遮光度为70％,简称S70）、CK（全光照）对凤仙花生长和开花的影响。结果表明：与CK相比,S45和S70的凤仙花株高分别增加了48．02％、34．16％,叶片数分别减少了8．28％、68．98％;两个遮阴处理组叶片叶绿素总质量分数分别比CK增加了1．31、1．39 mg· g－1,均达到极显著水平（ p＜0．01）,净光合速率分别减少了0．93、4．52μmol· m－2· s－1,也达到了极显著水平（ p＜0．01）;S45和S70的开花持续时间分别比CK减少了18、19 d,植株成活率分别降低了17．63％、33．75％,同时,CK、S45和S70在盛花期当日的平均开花量分别为2．78、4．20、3．50朵·株－1,至观测结束,CK、S45和S70的平均结实量分别为89．13、112．29、54．00个。因此,适度的遮阴有利于增加凤仙花植株的单株开花量,提高凤仙花的观赏价值,而过度的遮阴则会对凤仙花的生长甚至繁育产生不良影响。