The potential of South African indigenous plants for the international cut flower trade

A broad review is presented of recent developments in the commercialization of southern Africa indigenous flora for the cut flower trade, including potted flowers and foliages (“greens”). The botany, horticultural traits and potential for commercialization of several indigenous plants have been reported in several publications. The contribution of species indigenous and/or endemic to southern Africa in the development of cut flower crop plants is widely acknowledged. These include what is known in the trade as gladiolus, freesia, gerbera, ornithogalum, clivia, agapanthus, strelitzia, plumbago and protea. Despite the wealth of South African flower bulb species, relatively few have become commercially important in the international bulb industry. Trade figures on the international markets also reflect the importance of a few species of southern African origin. The development of new research tools are contributing to the commercialization of South African plants, although propagation, cultivation and post-harvest handling need to be improved. A list of commercially relevant southern African cut flowers (including those used for fresh flowers, dried flowers, foliage and potted flowers) is presented, together with a subjective evaluation of several genera and species with perceived potential for the development of new crops for the florist trade. It is concluded that research should be focused on potential markets rather than on preconceived product concepts. A special national effort is required to maximize the opportunities presented by the rich diversity of the flora and to develop an internationally competitive cut flower industry.     

Life beneath the surface of the central Texan Balcones Escarpment: genus Anillinus Casey, 1918 (Coleoptera,Carabidae, Bembidiini): new species,a key to the Texas species,and notes about their way of life and evolution

The Texas fauna of the genus Anillinus Casey, 1918 includes three previously described species (A. affabilis (Brues), 1902, A. depressus (Jeannel), 1963 and A. sinuatus (Jeannel), 1963) and four new species here described: A. acutipennis Sokolov & Reddell, sp. n. (type locality: Fort Hood area, Bell County, Texas); A. comalensis Sokolov & Kavanaugh, sp. n. (type locality: 7 miles W of New Braunfels, Comal County, Texas); A. forthoodensis Sokolov & Reddell, sp. n. (type locality: Fort Hood area, Bell County, Texas); A. wisemanensis Sokolov & Kavanaugh, sp. n. (type locality: Wiseman Sink, Hays County, Texas). A key for identification of adults of these species is provided. The fauna includes both soil- and cave-inhabiting species restricted to the Balcones Fault Zone and Lampasas Cut Plain and adjacent areas underlain by the Edwards-Trinity Aquifer. Based on morphological and distributional data, we hypothesize that four lineages of endogean Anillinus species extended their geographical ranges from a source area in the Ouachita-Ozark Mountains to the Balconian region in central Texas. There the cavernous Edwards-Trinity aquifer system provided an excellent refugium as the regional climate in the late Tertiary and early Quaternary became increasingly drier, rendering life at the surface nearly impossible for small, litter-inhabiting arthropods. Isolated within the Edwards-Trinity aquifer system, these anilline lineages subsequently differentiated, accounting for the currently known diversity. The paucity of specimens and difficulty in collecting them suggest that additional undiscovered species remain to be found in the region.     

多效唑对月季切花衰老的影响

本文研究了用多效唑处理的月季切花在瓶插期间的形态、生理变化,结果表明,多效唑能明显地缓解月季切花水分胁迫,改善体内水份平衡,促进切花开放,增加花朵鲜重和花径,抑制花瓣溶质外渗,延缓切花呼吸速率的下降和蛋白质降解的速率,从而延缓切花衰老。     

黑藻生产力的研究

黑藻是一种广泛分布于我国各地的野生沉水植物,但在南方的一些养鱼场进行了人工种植。本文报道了如下内容:黑藻生产力的测定值;水温、光强度和植株密度对黑藻生产力的影响;种黑藻养鱼池中溶氧、二氧化碳和pH的昼夜变化规律,以及黑藻断枝的无性繁殖。     

1-MCP-β-环糊精对香石竹切花保鲜作用的研究

对香石竹切花（Dianthus caryophyllus L．）用不同体积浓度的1-MCP-β-环糊精溶液处理不同的时间,观察其外观形态品质和生理生化指标,得知以50mg／L的1-MCP-β-环糊精溶液在7m^3的密闭体系中处理8h效果最佳。能极大提高香石竹切花的观赏价值,减少萎蔫程度,延缓开放,延迟香石竹切花叶片质膜相对透性下降,并对叶片叶绿素含量变化有一定的影响。     

Interspecific hybridization of Allium giganteum Regel: production and early verification of putative hybrids

 Cut flowers of Allium giganteum Regel were emasculated and maintained in half-strength Murashige and Skoog liquid medium supplemented with 3% sucrose and 1000 ppm each of Agrimycin^R and Benlate^R. Wide hybridization was attempted and, through embryo rescue, putative hybrids were obtained from crosses involving A. cernuum Roth, A. oreophilum C.A. Mey. and A. schubertii Zucc. PCR amplification of the internal transcribed spacer of ribosomal DNA followed by digestion with NdeII generated restriction profiles that confirmed the hybrid nature of the A. giganteum×A. schubertii progenies. The other putative hybrids were found to be products of self pollination. Received: 15 August 1997 / Accepted: 2 September 1997     

鸢尾切花保鲜的初步研究

本文通过对影响切花保鲜的pH值、切口处理、糖分、细菌数等的实验研究,初步探讨了不同配方保鲜剂对鸢尾切花保鲜的影响。     

保鲜剂对夏季香石竹切花衰老的延缓作用

香石竹切花瓶插期间花瓣中ＳＯＤ和蛋白质在前期上升,然后比处理组提前３天呈下降趋势。采后花瓣中ＣＡＴ、可溶性总糖和蔗糖均为下降。经由蔗糖、８－羟基喹啉和植物生长调节剂或钴镍盐组成的保鲜剂能延缓切花花瓣中ＳＯＤ、ＣＡＴ活性的下降,阻碍蛋白质、可溶性总糖和蔗糖的降解速度,同时使切花的瓶插寿命延长、含水量增加。     

Excised or intact inflorescences? Methodological effects on parasitoid wasp longevity

The development of accurate and repeatable experimental techniques is a cornerstone of any research program. Indeed, the first stage in developing a conservation biological control program typically involves ranking the suitability of various plant species as food resources for the target species of natural enemy in the laboratory or glasshouse. Herein the choice of flower presentation method is a highly relevant consideration. It is unclear whether excised flowers with their peduncles submerged in water will generate similar effects on the life history traits of a natural enemy compared with those using flowers remaining intact on a rooted plant. Either method has been used in 86 previous studies, yet none has quantified this effect. It is possible that both plant nectar content and production are altered as a result of changes in the physiological condition of the excised flowers. A laboratory test was designed to assess the influence of flower presentation method (excised or intact inflorescences) and different types of nectar (artificial and natural) on the longevity of the wasp Aphidius ervi, an important parasitoid of aphids. Distinct differences were revealed in the suitability of the nine flower species and three control treatments on parasitoid wasp longevity, with buckwheat being the most suitable plant. However, apart from coriander, flower presentation method and wasp gender generally did not affect parasitoid longevity for the set of species tested. As there was little evidence that parasitoid wasp longevity would be altered on excised flowers, and because of reasons pertaining to improved logistical and experimental requirements, the use of excised flowers is cautiously recommended to researchers for further laboratory evaluations of the effects of nectar provision on parasitoid fitness.