黑醋栗种苗培育试验研究

醋栗扦插以皮部生根为主，扦插生根期２０天左右，生根部位集中在扦插入土深５－１５ｃｍ之间。３年生以下枝皮层老化，枝条芽为潜伏芽，扦插不易生根和成活。经不同方法扦插试验，醋样扦插适宜采条时间为１１月下旬，冬季采条沙藏比春季剪条提高扦插成活２８％，插穗的适宜长度为１５－２０ｃｍ，适宜粗度为０．７－１．２ｃｍ。同根枝条剪穗的适宜部位为下、中部枝段；插穗年龄以１－２年生扦插成活率为高，压条成苗率是压条数的１     

Growth of Roots Emerged from Excised Phytomers of Three Gramineous Species under a Low Osmotic Potential

Abstract

The growth of crown and lateral roots emerged from the excised phytomers of pearl millet (Pennisetum typhoideum Rich.), barnyard millet (Echinochloa frumentacea Link.) and maize (Zea mays L.) was studied under normal and low osmotic potential conditions. The plants were grown in two solutions with osmotic potentials of –0.02 and –0.54 MPa for 6 days. The relative growth rate of the roots in total length (RGR_L) , was not affected by osmotic stress in pearl and barnyard millets, but that in stressed maize was reduced to 64% of the control. Similarly, the relative growth rate of the roots in dry weight (RGR_W), was not affected by osmotic stress in pearl and barnyard millets, but significantly reduced in maize. Osmotic stress increased the specific root length of the lateral roots in pearl and barnyard millets, but did not affect that of maize. The photosynthetic rate (Pr) in the two millets was decreased to ca. 60% of the control by the stress, and that in maize was reduced to 21%. Under the stress, Pr in the three species was limited mainly by low stomatal conductance, but no clear relationship was found between Pr and osmotic adjustment of the leaf. The relative water content of the leaf was lower in maize than in the two millets. The resistance to water flow through the phytomer (R) was significantly increased by osmotic stress in maize, but not significantly in the two millets. The mean root length (RL) was decreased by the stress in maize, but not in the two millets. The maintenance of RGR_L in the two millets was associated with sustained R, RL and also with the maintenance of Pr and allocation of assimilates to roots.     

Geographical distribution of wild <Emphasis Type="Italic">Daucus</Emphasis> species in the natural grasslands of the Argentinian pampas

Three wild carrot species have been reported in the argentinian flora: Daucus montanus Humb. et Bonpl. ex Schult., D. montevidensis Link ex Sprengel and D. pusillus Michx. There is a discrepancy among authors about the distinctive morphological traits of the last two species; thus, it is difficult to ascertain if they are truly two distinct taxa. Based on the available literature and in the search of a paradigmatic site, four collection trips were carried out in 2004 and 2005 in Buenos Aires and Southern Entre Ríos provinces. Populations were sampled at 30 sites, and local environmental parameters and associated plant species were recorded. Morphological observations and chromosome counts were carried out on 10 plants/population. Three morphological phenotypes were distinguished: one in 18 populations, all with 2n = 2x = 18, and two in the remaining 12, with 2n = 2x = 22 or aneusomaty (2n = 2x = 20, 22). Populations of the first phenotype were assigned to wild D. carota and the rest, tentatively, to D. pusillus (D. montevidensis?), till further evaluations are carried out in test sites to verify this tentative conclusion.     

西藏龙胆根内寄生附球霉属真菌菌株特性研究

[目的]研究西藏龙胆根内寄生附球霉属真菌的菌株特性。[方法]以从新鲜西藏龙胆根部内分离得到的附球霉属菌株为材料,对其进行菌株鉴定与形态学观察。[结果]①菌株在PDA培养基和察氏培养基上菌落舒展,呈白色垫状,菌落到后期变为黄色,孢子黑色,基质呈黄色;而在KB培养基上菌落舒展,呈白色绒毛状,菌落到后期变黄色,孢子黑色,基质呈黄色;②菌株在25℃下培养2 d后,分生孢子在黄色菌落表面形成分散的点状黑色菌落,并有黄色色素分泌。[结论]通过相关文献查阅,发现分离得到的菌株属半知菌亚门丝孢纲瘤座孢目附球霉属的一种;菌株孢子的外形与附球霉孢子的外形相似,但在孢子纵、横隔膜隘缩的描述和柄细胞结构上与有关文献的描述有区别。     

Host Link在燃气炉自动控制系统上的应用

文章介绍基于高速调温烧嘴燃气加热炉的全自动计算机智能控制系统的方案,实现自动点火、自动监测火焰、脉动式燃烧、自动控温、熄火报警保护、数据的显示与记录等功能。并采用CPM1AH的Host Link通信功能及智能PID控制技术,合理优化控制,使燃气在炉内能充分燃烧,既节省能源,又减少了大气的污染、保护了环境。     

浅谈黑豆果栽培技术

根据黑豆果的生物学特性,阐述了黑豆果的栽培技术、营养价值,黑豆果的种类、扦插技术、生长期、一般的田间管理。     

甘肃省临夏州小麦脚腐病病原鉴定

对甘肃省临夏州小麦脚腐病病原进行了分离鉴定,从3块病田的37株罹病小麦上分离得到56个真菌菌株,分别被鉴定为雪腐镰刀菌[Fusarium nivale(Fr.)Ces.]、燕麦镰刀菌[Fusarium avenaceum(Corda et Fr.)Sacc.]、麦斑点附球霉[Epicoccum triticiP.Henn.]、小壳色单隔孢菌[Diplodiellasp.]、交链孢菌[Alternariaspp.]、芽枝霉[Cladosporiumsp.]、黑孢霉[Nigrosporasp.]。其中,雪腐镰刀菌致病性最强,燕麦镰刀菌致病性中强,麦斑点附球霉致病性弱,其余菌不致病。     

胡椒资源ISSR遗传多样性研究

利用简单重复序列区间(ISSR)技术分析来自不同国家的56份胡椒种质资源的遗传多态性。结果显示:7条引物共产生141条清晰的谱带,分子量在0.2~3.0 bp之间,多态位点百分率达100%,在一定程度上说明胡椒资源遗传的复杂性和多样性。在相似性系数约为0.51的水平上将56份资源聚为3个类群,与基于ITS的研究结果类似。大胡椒与其它种质的亲缘关系均比较远,显示出其明显的差异性和独特性,与其形态学分类结果一致,同时支持将顶花胡椒、光轴苎叶蒟归入苎叶蒟,光茎胡椒作为一个变种。     

胡椒果实灌浆期喷施叶面肥和GA3对其光合性能的影响

在胡椒果实灌浆期,施用叶面肥、GA3、GA3+叶面肥、清水观察对植株光合性能的影响.结果表明,叶面肥或GA3能明显地增加叶绿素含量,提高光合强度,促进光合产物的合成,加强光合产物向果实的运输,增加百果干重.各处理的作用效果以叶面肥+GA3最明显,单施叶面肥好于单施GA3.     

四川省山药黑斑病病原菌的鉴定

为鉴定引起山药茎蔓黑斑病的病原菌,本研究利用柯赫氏法则验证其致病性,根据菌株的形态特征和基于rpb2基因序列分析进行分类鉴定,并初步测定其寄主范围。结果显示:分离的2株病原菌分生孢子椭圆形,单胞,(3.9～5.1)μm×(1.8～2.7)μm,产孢细胞瓶梗形,分生孢子器近圆形或梨形,无刚毛,具孔口,有时孔口延长形成乳突,NaOH颜色反应呈阳性,参考Phoma鉴定手册,可将其划分到section Peyronellaea。将供试菌的rpb2序列进行BLAST比对分析,其与GenBank中的Epicoccum latusicollum具有最高的同源性,支持率为97%,结合形态学特征可将其鉴定为E.latusicollum,该菌经人工接种后也能侵染番茄、辣椒和花菜幼苗。