腔孢纲一新属——类腊肠茎点霉属

近年甘肃省河西走廊一带胡萝卜上发生一种叶斑病,严重时造成减产20%~30%。其病原物为丝分孢子真菌(半知菌)腔孢纲Coelomycetes中一未描述的真菌。该菌具有分生孢子器,但其形态与相似属茎点霉属Phoma、鞘茎点霉属Coleophoma和拟腊肠茎点霉属Allantophomopsis不同,遂建立类腊肠茎点霉属Allantophomoides(新属);其模式种为胡萝卜类腊肠茎点霉Allantophomoidescarotae(新种)。研究的标本保存在山东农业大学植物病理学标本室(HSAUP)。     

苏木科植物上的拟茎点霉新种及中国新纪录种

报道了苏木科植物上的两个拟茎点霉 Phomopsis 新种：羊蹄甲生拟茎点霉 Phomopsis bauhinicola 和决明生拟茎点霉 Phomopsis cassiicola ,和两个中国新记录种：羊蹄甲拟茎点霉 Phomopsis bauhiniae 和决明拟茎点霉 Phomopsis cassiae 。新种附有拉丁文、英文描述和显微结构图。模式标本保存于华南农业大学真菌标本室(HMA)。     

采自广州的六个拟茎点霉新种

报告了采自广州的六个拟茎点霉Phomopsis新种：金合欢生拟茎点霉Phomopsis acacicola、叶子花生拟茎点霉Phomopsis bougainvilleicola、樟生拟茎点霉Phomopsis cinnamomicola、八宝树拟茎点霉Phomopsis duabangae、杜鹃拟茎点霉Phomopsis rhododendri和黄花夹竹桃拟茎点霉Phomopsis thevetiae。新种附有拉丁文、英文描述和显微结构图。模式标本保存于华南农业大学真菌标本室(SCHM)。     

广东省草本花卉上的拟茎点霉新种和新记录种

报道了采自草本花卉上的一个拟茎点霉Phomopsis新种(千日红拟茎点霉Ph.gomphrenae)和两个中国新记录种(风仙花拟茎点霉Ph.impatientis与埋生拟茎点霉Ph.immersa)。新种千日红拟茎点霉的甲乙型分生孢子不论长度还是宽度均小于之前报道的两个拟茎点霉,并且缺少第三种分生孢子。新种附有拉丁文描述及显微结构图。模式标本保存于华南农业大学真菌标本室(SCHM)。     

采自广州的六个拟茎点霉新种

报告了采自广州的六个拟茎点霉Phomopsis新种:金合欢生拟茎点霉Phomopsis acacicola、叶子花生拟茎点霉Phomopsis bougainvilleicola、樟生拟茎点霉Phomopsis cinnamomicola、八宝树拟茎点霉Phomopsis duabangae、杜鹃拟茎点霉Phomopsis rhododendri和黄花夹竹桃拟茎点霉Phomopsis thevetiae。新种附有拉丁文、英文描述和显微结构图。模式标本保存于华南农业大学真菌标本室(SCHM)。     

温室茄子茎直径微变化与作物水分状况的关系

在温室条件下,采用盆栽土培和小区试验相结合的方法,以茄子(Solanummelongena,品种新乡糙青茄)为材料进行了植株茎直径微变化(膨胀或收缩)与作物体内水分状况的关系试验研究,旨在为利用茎直径微变化无损快速诊断作物水分状况提供理论依据。盆栽和小区试验均采用两因素(土壤水分梯度和作物不同生育阶段)随机区组设计,土壤水分控制下限分别取田间持水量的80%FC(Fieldwatercapacity),70%FC,60%FC和50%FC;生育阶段分别为苗期、花果期和采收期;共有4×3=12个处理组合,重复3次。结果表明:无论是在较高土壤含水量或在较低土壤含水量条件下,在晴好的天气里,茄子茎直径都是在白天收缩,傍晚、夜间复原或膨胀,而且这种微变化动态与植株体内的水分状况密切相关,不同土壤含水量条件下植株茎胀缩的幅度存在明显差异。高水分条件下,植株茎收缩幅度小,复原能力强;低水分条件下,植株茎收缩幅度大,恢复能力差。茎直径变化对环境因子水汽压差(VPD)的响应比较敏感,二者呈正相关关系,相关系数R2为0·8938。茎直径变化量(ΔSd)与叶水势(ψL)、叶片相对含水量(LRWC)呈极显著正相关关系,相关系数R2分别为0·867和0·965。这些结果显示,茎直径变化量能灵敏、实时、准确地反映植株体内的水分状况;与其它作物水分诊断方法(叶水势法,叶片相对含水量法,细胞液浓度法等)相比,茎直径微变化法可能具有简便、稳定、无损、连续监测和自动记录的优势。     

木本植物茎中的凝集素

凝集素的发现迄今已有一百来年的历史,但凝集素的生理功能却一直是众说纷纭,至今尚未有一个定论。近来动物凝集素的生理功能研究已取得了一定的进展,而植物凝集素方面则仍无多大起色。不过最近对木本植物茎中凝集素(主要是树皮凝集素)的生理功能,倒是提出了一些颇有意义的看法。血凝活力广泛存在于木本植物茎的抽提液中,据推测存在一种与茎的增厚有关的凝集素。树茎中的凝集素一般呈现结合GlcNAc或GalNAc残基的专一性。不过最近却发现了几个不同寻常的凝集素:一个结合含唾液酸(NANA)的寡糖,另一个结合Man。对这些凝集素的生理功能知道得很少,并且     

采自西双版纳的三个拟茎点霉新种

报道了采自云南西双版纳的三个拟茎点霉Phomopsis新种:猴面包树拟茎点霉Ph. adansoniae、橡胶生拟茎点霉Ph. heveicola和蒲桃生拟茎点霉Ph. syzygiicola。猴面包树拟茎点霉分生孢子梗较长且宽,甲型分生孢子纺锤形,不同于木棉科植物上已报道的拟茎点霉种。橡胶生拟茎点霉与橡胶拟茎点霉Ph. heveae的主要区别在于前者分生孢子梗较宽,甲型和乙型分生孢子较窄。蒲桃生拟茎点霉与蒲桃拟茎点霉Ph. syzygii的主要区别是前者分生孢子梗合轴分枝,甲型分生孢子具2个油球。新种附有拉丁文、英文描述及显微结构图。模式标本保存于华南农业大学真菌标本室(SCHM)。     

腔孢纲一新属--类腊肠茎点霉属

近年甘肃省河西走廊一带胡萝卜上发生一种叶斑病,严重时造成减产20%~30%.其病原物为丝分孢子真菌(半知菌)腔孢纲Coelomycetes中一未描述的真菌.该菌具有分生孢子器,但其形态与相似属茎点霉属Phoma、鞘茎点霉属Coleophoma和拟腊肠茎点霉属Allantophomopsis不同,遂建立类腊肠茎点霉属Allantophomoides(新属);其模式种为胡萝卜类腊肠茎点霉Allantophomoides carotae(新种).研究的标本保存在山东农业大学植物病理学标本室(HSAUP).     

毛茛组织培养与植株再生(简报)

以毛茛（Ranunculus japonicus）茎尖、带芽茎段为外植体进行组织培养。试验结果表明,毛莨茎尖、带芽茎段萌发快,茎段丛生芽增殖数多于茎尖;壮苗和生根可在MS0培养基上一次完成,生根率达85％。     

魔芋茎尖组织培养和植株再生的研究

以魔芋茎尖、幼芽为外植本,接种于１／２ＭＳ＋１．０ｍｇ／ＬＢＡ＋０．０１ｍｇ／ＬＮＡＡ的培养基中,茎尖、幼芽逐渐生长直接形成幼芽或幼苗;或从茎尖、幼芽由来的膨大的块茎组织表面诱导出幼芽。膨大的块茎组织分割后接种于ＭＳ＋０．０１ｍｇ／Ｌ＋０．０１ｍｇ／ＬＮＡＡ的培养基中进行增殖培养,同时从增殖的块茎组织表面不断地诱导出幼芽。幼芽切块转入不含激素的ＭＳ培养基中,形成幼苗。幼苗切块转入ＭＳ＋０．１ｍｇ／ＬＮＡＡ的生根培养茎中,幼苗生根,形成完整的植株。试管苗移栽６个月后获得干块茎。     

鹤望兰组织培养与工厂化快繁程序的研究

将材料接种于诱导愈伤组织手芽的培养基上,培养２个月后,胚芽外植体下出现白色颗粒状的愈伤组织,４个月后愈伤组织上出现小芽丛。将小芽丛转入不加植物激素的ＭＳ培养基上,芽的生长加快,２个月左右可长成３－６ｃｍ高的丛小植株。将小植株切下,插入根培养基中,一般３５ｄ左右基部突出很小的白色根尖。     

紫斑牡丹休眠地下芽在组织培养条件下的发育研究

以紫斑牡丹（Paeonia rockii T.Hong et Li J.J.)休眠地下芽为材料,对同一时期打破休眠的地下芽在3种不同培养基上的发育状况、不同时间低温处理后在同一培养基上的发育,以及不同时期休眠地下芽在同一培养条件下的发育进行了比较研究。结果表明：MS＋BA 1mg/L NAA 0.5mg/L 2,4-d 0.5mg/L最有利于打破休眠的地下芽发育;不同低温处理对休眠地下芽的萌发率及发育速率作用明显不同,其中,720h的低温处理效果最佳;彻底打破休眠的不同时期地下芽在同一培养条件下发育速率基本一致。     

THE PHYSIOLOGICAL BASIS OF MORPHOLOGICAL POLARITY IN REGENERATION. II

1. The experiments show that the mass of air roots formed in a stem increases with the mass of the leaf attached to the stem, though it has not been possible to establish an exact mathematical relation between the two masses, owing to unavoidable sources of error. 2. Darkened leaves do not increase the mass of roots formed. 3. In stems suspended horizontally air roots appear on the lower side of the stem, with the exception of the cut end where they usually appear around the whole circumference of the stem. When the lower half of a stem suspended horizontally is cut off, roots are formed on the upper side. It is shown by experiments on leaves suspended horizontally that the more rapidly growing roots and shoots on the lower side inhibit the root and shoot formation in the upper half of such a leaf; and likewise the more rapid formation of roots on the lower side of a horizontally suspended stem seems to account for the inhibition of root formation on the upper side of such a stem. Likewise the more rapid growth of shoots on the upper side of a stem suspended horizontally is likely to inhibit the growth of shoots on the lower side. 4. Each leaf contains in its axil a preformed bud capable of giving rise to a root, which never grows out in the normal stem on account of the inhibitory influence of the normal roots at the base of the plant. These dormant root buds are situated above (apically from) the dormant shoot bud. The apical root buds can be caused to develop into air roots when a piece of stem is cut out from a plant from which the leaves except those in the basal node of the piece are removed. The larger these basal leaves the better the experiments succeed. 5. These apical air roots grow out in a few days, while the roots at the basal end of the stem (which in our experiments dip into water) grow out about a week later. As soon as the basal roots grow out in water they cause the air roots in the more apical region of the stem to dry out and to disappear. 6. In addition to the basal roots, basal nodes have also an inhibitory effect on the growth of the dormant root buds in the apical region of a stem. This is indicated by the fact that a stem with one pair of leaves near the base will form apical air roots more readily when no node is situated on the stem basally from the leaf than if there is a node basally from the leaf.     

Micropropagation of lily (Lilium longiflorum) via in vitro stem node and pseudo-bulblet culture

A protocol for micropropagation of Lilium longiflorum using pseudo-bulblets from in vitro shoot-tip-derived stem nodes was developed. Shoot tips from stems of dormant bulbs were cultured on one-half Murashige and Skoog (MS) medium. Stems from plantlets derived from the shoot tips were cut into nodal segments, which were then cultured on one-half MS medium supplemented with 1 μm 6-benzyladenine (BA). Pseudo-bulblets formed on each node after 1 month. An average of 32 pseudo-bulblets were formed on all nodes of the plantlet. Pseudo-bulblets gave rise to multiple shoots when cultured on one-half MS medium supplemented with 2.3 μm BA. Shoots were rooted on one-half MS medium containing 1.1 μm α-naphthaleneacetic acid. A continuous system of propagation by multiplication of pseudo-bulblets with no dormancy period was developed. The 80 flowering plants produced from shoot tip culture were acclimatized in the greenhouse for 3 months and then grown in the experimental garden for 8 months. Received: 29 October 1997 / Revision received: 28 April 1998 / Accepted: 3 May 1998     

The Control and Branch Growth on Potato Tubers: I. ANATOMY OF BUDS IN RELATION TO DORMANCY AND CORRELATIVE INHIBITION

A study was made of the morphology of potato buds during thedormant period and of the anatomy of dormant, growing, and correlativelyinhibited buds. Lateral buds showed a progressive increase indevelopment with increasing number of nodes measured basipetally,and some further development in association with second-growthof the tuber. In dormant buds, or buds which had not grown afterthe end of the rest period, the cytoplasm of cells in the meristematicdome stained only lightly with Heidenhain's iron-hematoxylin,whereas cells of buds which had grown had densely staining cytoplasm.The xylem vessels leading to dormant buds were filled with tannin-likesubstances for a short distance below the bud. Buds which hadgrown after the end of the rest period had both old obstructedxylem vessels and new open vessels. The end of the dormant period was not reflected in the internalbud anatomy unless buds also commenced to grow. Thus, whiledormant buds had distinctive anatomical features, none of thestructures appeared to be primarily associated with dormancy.Correlatively inhibited buds showed the features either of dormantor of growing buds depending on whether or not they had grownat the end of the dormant period.     

Twig pre-harvest temperature significantly influences effective cryopreservation of Vaccinium dormant buds

Cryopreservation of temperate woody-plant material by dormant buds is less expensive than using shoot tips isolated from tissue cultured plants; however currently, dormant buds are used only for preservation of selected temperate tree and shrub species. Using dormant buds could be an efficient strategy for long-term preservation of blueberry (Vaccinium L.) genetic resources. In this study, viability of V. hybrid ‘Northsky’ (PI 554943) dormant buds was evaluated at 30 harvest dates over three consecutive fall/winter seasons to determine the optimal harvest time that promotes high post cryopreservation viability. Twigs with dormant buds were cut into 70 mm segments containing at least two nodes, desiccated, slowly cooled, stored in liquid nitrogen vapor and tested for post-cryopreservation regrowth. The highest regrowth of cryopreserved dormant buds was observed for buds harvested in mid-December and during the first half of January. Pearson's correlation coefficients were computed to evaluate the association between bud characteristics and viability at harvest date and logistic regression models were fit to test the ability of twig characteristics and temperatures to predict post cryopreservation bud viability. Post-cryopreservation viability was negatively correlated (p < 0.05) with average minimum, maximum and daily mean temperature preceding the bud harvest but was not correlated with the dormant bud initial and end moisture content, twig diameter, the number of dormant buds/cm of twig length and the number of days in desiccation. Regression tree analysis suggested post-cryopreservation viability to be between 52 and 80% for dormant buds harvested after a 10 day average maximum air temperature of <11.2 °C. Pre-harvest air temperature was a significant indicator of optimal dormant bud harvest time to produce adequate viability for long term preservation of blueberry genetic resources.     

唐菖蒲球茎芽的离体培养及快速繁殖

将带1-2个芽眼的唐菖蒲球茎切块接种到附加1.0mg/LBA的MS基本培养基上可诱导休眠芽萌动、无菌芽转移至附加3.0mg/LBA的培养基上可分化产生丛生芽。丛生芽的继代增殖宜采用附加1.5mg/LBA的培养基生根培养,以MS+NAA 0.1-0.5mg/L或MS+IBA 1.5mg/L效果最佳。试管苗移栽存活率可达50%左右。     

亳芍茎尖组织培养的研究

选取亳芍茎尖为试验材料,探究不同培养条件对亳芍组织培养的影响,结果表明:亳芍茎尖在1/2MS+6-BA 1.0 mg/L培养基上培养39 d后,茎尖分化出芽的同时也形成较多的丛生芽;丛生芽在1/2MS+6-BA1.0mg/L培养基上增殖速度最快;来自不同启动培养基上的丛生芽在相同培养基上,接种15 d后观察,不同来源的丛生芽长势不同,30 d后仍存在一定的差异;幼苗在1/2MS+IBA 0.1生根效果最好。     

Floral-stimulus activity in tobacco stem pieces

The growth patterns of axillary buds of dayneutral tobacco (Nicotiana tabacum L. cv. Wisconsin 38) plants were assessed by using expiants of single buds attached to leafless stem cuttings and allowing the buds to grow to flowering without additional manipulation. Buds located 5, 10 and 15 nodes below the inflorescence were employed. For a given bud position, when a cutting had few internodes the growth pattern of a bud tended to fall into one of two groups: buds that produced few-noded shoots and buds that produced many-noded shoots. For example, in a group of 13 cuttings composed of bud 5 with 2 associated internodes, 11 buds produced 14.2 nodes (range, 11–17) and 2 buds produced 32.0 nodes (range, 30–34). As the number of internodes on the cutting increased, the number of buds producing few-noded shoots increased and the number of nodes produced decreased (e.g. in contrast to the data above, all 5th buds with 6 internodes produced 12.8 nodes; range 11–15). When cuttings from the 3 positions had the same number of internodes, the more apical cuttings had buds that produced fewer nodes (e.g. for cuttings with 6 internodes all 5th buds produced 12.8 nodes, all 10th buds produced 15.5 nodes and 85% of 15th buds produced few-noded shoots with 19.3 nodes). The number of nodes produced by a bud was a function of the original position of the stem piece and not the original position of the bud. That is, bud 5 associated with the 6 internodes below it produced 12.8 nodes and bud 10 associated with essentially the same 6 internodes (i.e. the 6 above it) produced 12.9 nodes while bud 10 associated with the 6 internodes below it produced 15.5 nodes. Thus, the number of nodes produced by a bud was dependent upon the original main-axis position of the cutting as well as the number of internodes on the cutting. Buds forced to grow out in situ on main axes devoid of leaves produced substantially more nodes than similar buds on cuttings. Buds isolated without associated internodes produced many-noded plants with a number of nodes similar to that of plants grown from seed. The simplest interpretation of these data is that stem pieces contain floral-stimulus activity and that this activity is present in a gradient with the highest activity being located in the apical part of the stem.We thank Susan Smith and Harry Roy (Rensselaer) for comments, and the National Science Foundation for financial support (IBN-9003739 to C.N.M.).