沙地樟子松人工林土壤磷素转化的根际效应

对大青沟自然保护区内不同年龄樟子松人工林根际和非根际土壤中不同形态磷素含量和酸性磷酸单酯酶（AP）活性进行了比较.结果表明,樟子松根系活动显著地提高了根际土壤有机碳含量及有机质的C/P比,增强了土壤微生物活动和AP活性,促进了有机磷的可利用性与矿化;显著地降低了土壤pH值,促进了Ca-P的溶解;从而提高了土壤磷素的有效性,促进了有机磷和Ca-P向Fe-P、Al-P的转化.与AP活性的根际效应相反,随林龄增加,樟子松对各形态磷素的根际效应逐渐增强,根际和非根际土壤中各形态磷素的变化趋势基本一致,土壤全磷和有机磷含量逐渐下降,而活性磷含量升高.为了保持土壤有机磷库和磷素的持续供应,必须对地被物予以保护.     

根际微生物产生的植物激素对小麦生长的作用（简报）

根际微生物PGI和PG6培养液中含有生长素、赤霉素和细胞分裂素。用PGI和PC6接种小麦能显著促进幼苗的生长发育,它们对幼苗根形态的影响与植物激素处理的效果相似。施加生长素和细胞分裂素的生理前体色氨酸及腺嘌呤和异戊醇更加促进PG1和PG6对小麦幼苗根茎的生长。关键词##4根际微生物;;植物激素;;小麦     

植物激素对人参毛状根生长和皂甙含量的影响

就植物激素IAA、IBA、NAA、2,4-D对人参（Panax ginseng C.A.Meyer）毛状根生长及皂甙含量的影响进行了研究。结果表明,4种生长素在适宜的浓度下均可不同程度地促进人参毛状根的生长以及皂甙的积累,同时能影响单体皂甙的分布。NAA和IBA能显著促进毛状根的生长,其中0.500mg/L IBA能显著促进毛状根生长和总皂甙的积累。细胞分裂素6-BA在较低浓度时虽然对生长无明显的促进作用,但对皂甙积累有利,同时显著促进单体皂甙Rb1的积累,增大Rb1在总甙中所占的比例。     

KT和NAA对黄芪带芽茎段增殖、愈伤诱导和生根的影响

通过建立组织培养快繁体系,探讨KT和NAA对膜荚黄芪茎段诱导生成新生茎、愈伤组织及生根的影响。KT/NAA值为4时,对茎的诱导作用明显,获得最多的茎平均数(11.7条)。NAA促进愈伤组织形成,在1 mg/L NAA作用下最大的平均直径为1.4 cm,多为白色。根生于白色愈伤组织,并受NAA促进、KT抑制。1 mg/L NAA对根数、根长和次级根数均有促进作用,但对根粗有抑制作用。     

香根草定植前几种催根法的比较研究

为了解催根对香根草成活率及生长的影响,采用浸根、浆根、水培、沙植和稻壳培植五种催根方法,分别给予除氯自来水和25 mg/L IAA两种条件,在定植前对香根草进行处理,与对照组进行对比试验.结果表明:各种催根方法都能有效提高成活率和草苗的日均生长高度;IAA的效果最佳;IAA能促进新根的产生、生长,以浆根 IAA最明显;从定植后草苗的长势看,IAA的效果更明显,以浆根 IAA最好.综上所述,定植前对草苗进行催根处理是必要的,以25 mg/LIAA浆根效果最好,而且简便易行.     

“根际微生物”专刊征稿函

自1904年德国科学家Lorenz Hiltner提出根际概念以来,其研究内容不断得以丰富和发展。根际是植物吸收的关键门户,是实现农业绿色发展的关键调控区域。根际微生物对植物的生长和健康发挥重要作用,被看作是植物的第二基因组,类似于肠道微生物对人体的功能。根际微生物中的益生菌具有活化根区养分、促进植物生长、增强植物抗逆、抑制土传病害等功能,是微生物肥料和微生物农药的主要菌种来源。随着国内外微生物组研究的开展,根际微生物组的整体功能更受关注,充分挖掘根际微生物组的功能促进作物增产是农业微生物的主要研究前沿之一。     

AM 真菌影响三叶草根系抗氧化酶活性的系统效应

本文对三叶草接种AM 真菌根内球囊霉, 用盆栽试验和分根试验测定根系的菌根侵染率和抗氧化酶活性, 研究AM 真菌对根系抗氧化酶活性的影响以及该影响的系统性。结果表明, 盆栽试验中接种根内球囊霉显著提高了根系中SOD、POD、CAT 的活性, 表明AM 真菌可以促进根系的抗氧化酶活性; 分根试验中一半根系接种了根内球囊霉的植株, 其另一半未接种的根系SOD、POD 活性也增加, 表明AM 真菌对根系抗氧化酶系统的促进具有系统效应。由于抗氧化酶系统是植物产生抗逆性的生理生化基础, 可以推测, AM 真菌对根系抗氧化酶活性的系统性提高有助于保护根系整体, 而非仅仅保护受侵染根段。     

茉莉酸甲酯和ABA对野葛毛状根中异黄酮含量的影响

10～ 10 0 μmol·L-1茉莉酸甲酯 (MJ)可提高野葛毛状根培养液中葛根素和大豆甙元的水平 ,促进毛状根内总异黄酮含量的增加。而用 0 .5～ 2 .0mg·L-1ABA处理后 ,无论对野葛毛状根还是培养液中葛根素、大豆甙元的含量仅略有提高 ,但对总异黄酮的合成与分泌等则有显著的促进。 10 0 μmol·L-1MJ和 1mg·L-1ABA处理 2 4～ 72h ,可促进毛状根内葛根素和培养液中总异黄酮的水平 ,以处理 4 8h的增加量最大     

4,4,4-三氟-3-(吲哚-3-)丁酸和吲哚丁酸对水稻和莴苣幼苗种子根长度及侧根原基发生的影响

适宜浓度的TFIBA 显著促进了莴苣和水稻初生种子根的伸长生长,抑制了水稻种子根侧根原基的发生,但对莴苣侧根原基的发生无任何作用,对根顶端优势的调控与IBA相反.     

酵母葡聚糖对丹参毛状根过氧化物酶和苯丙氨酸解氨酶的影响

为利用转化的丹参毛状根生产丹参中的药理活性物质,从啤酒酵母细胞壁中应用碱处理方法制备β-1,3-葡聚糖。利用全酵母细胞壁和酵母葡聚糖的水解产物分别诱导悬浮培养的丹参毛状根,比较它们对丹参毛状根的形态和根组织过氧化物酶、苯丙氨酸解氨酶的影响。结果表明,酵母葡聚糖比全酵母细胞壁水解产物更显著促进丹参毛状根组织的过氧化物酶和苯丙氨酸解氨酶的总活性,酵母葡聚糖的诱导效应具有浓度依赖性和时效性。酵母葡聚糖显著促进丹参毛状根的生长和根端膨大。葡聚糖是有潜力的丹参生长和次生代谢调节剂。     

三种方法诱导熊本牡蛎三倍体的比较研究

为获得高效的熊本牡蛎的三倍体诱导方法, 分别比较了6-DMAP、高盐和低盐3种诱导方法在不同的诱导浓度(盐度)、起始诱导时间和持续诱导时间下的卵裂率、孵化率和三倍体率, 同时比较了3种方法获得的幼虫的生长、存活和三倍体率变化情况。结果表明, 在6-DMAP诱导组中, 三倍体率和诱导效率分别可达37.97%—58.01%和34.30%—42.50%, 培育期间幼虫的平均存活率27.19%, 生长率13.03 μm/d, 三倍体率降低了24.94%; 在低盐诱导组中, 三倍体率和诱导效率分别可达7.32%—42.25%和2.17%—31.41%, 培育期间幼虫的平均存活率33.92%, 生长率12.71 μm/d, 三倍体率降低了20.64%; 在高盐诱导组中, 三倍体率和诱导效率分别可达7.47%—63.03%和6.58%—49.41%, 培育期间幼虫的平均存活率31.66%, 生长率13.08 μm/d, 三倍体率降低了17.64%。综合来看, 高盐诱导是诱导三倍体熊本牡蛎的最优方法, 其诱导条件的最佳组合为盐度55, 起始诱导时间受精后15min, 持续诱导时间20min。研究为熊本牡蛎的三倍体诱导提供了技术支持, 对熊本牡蛎的多倍体育种具有重要的理论指导意义。     

PATTERNS OF RELATIVE GROWTH IN NEREOCYSTIS LUETKEANA (PHAEOPHYTA)1

Plants of Nereocystis luetkeana (Mert.) Post. et Rupr. of different sizes were held on a raft at the surface of the sea off the Friday Harbor Laboratories, San Juan Island, Washington for 5 day periods for observation of detailed relative growth of different parts. Each stipe was marked at intervals with injected Indian ink and each blade was punched with a series of holes. Measurements of diameter, length, width and thickness were made before and after the 5 day periods. Blades showed a very similar pattern of relative growth rate (R) over an 18-fold range of sizes. The maximum local R in length was about 0.2 day⁻¹ and occurred at 6.5% of the distance from the bulb to the tip, declining to 0.01 at half way. Half the linear growth occurred in the proximal one tenth of the blade and 95% within the proximal half. The relative growth rate of the whole blade declined only slightly with increased size and lay between 0.0.3 and 0.06 day⁻¹ (approx. 3–6% day⁻¹). The linear growth rate therefore increased with blade size, the maximum observed being 14 cm day⁻¹. The maximum relative growth rate in blade width was slower, and sited more distally than that in length. Unless fertile tissue was involved all blade tissue, except that closely adjoining the bulb, became thinner during growth. R in volume reached 0.3 day⁻¹. Presumably because the plants were held near the sea surface stipes grew slowly, with a maximum linear rate of 9 mm day⁻¹. The maximum R in length decreased with stipe length. Bulb R in volume also decreased as size increased, from a maximum of 0.3 day⁻¹.     

多效唑对水稻未成熟胚愈伤组织诱导,分化和壮苗培养的影响

多效唑(Mult-Effect Triazole,MET)是一种良好的植物生长延缓剂,具有多方面的生理效应。已在水稻、小麦、油菜等作物中应用。本文报道了多效唑对水稻未成熟胚愈伤组织诱导、分化以及对壮苗培养的影响,为植物试管苗的正常化生产提供了有效的化学调控措施。1.材料早粳“T53”未成熟胚,愈伤组织,再生绿芽;早籼87-5-0,“湘竹443”再生绿芽。多效唑由本所生理系提供。     

La3+对墨兰根状茎某些细胞器发育的影响

以１／２ＭＳ＋ＢＡ（１ｍｇＬ－１）＋ＮＡＡ（１ｍｇＬ－１）＋Ｌａ３＋（１０ｍｇＬ－１）培养墨兰根状茎３０ｄ后,取样观察根状茎细胞叶绿体、线粒体和细胞核的发育特点并与对照进行比较,发现：①处理组叶绿体发育较快,有较丰富的片层结构和嗜锇颗粒,而对照组的发育慢,含大型的淀粉粒,无明显的片层结构．②处理组线粒体体积较大,内含物较丰富,而对照组的较小,内含物较少。③处理组细胞核内的染色质较对照组丰富．上述结果表明,ｔａ３＋对墨兰根状茎细胞器的发育有一定的调节作用。     

PATTERNS OF RELATIVE GROWTH IN NEREOCYSTIS LUETKEANA (PHAEOPHYTA)1

Plants of Nereocystis luetkeana (Mert.) Post. et Rupr. of different sizes were held on a raft at the surface of the sea, off the Friday Harbor Laboratories, San Juan Island, Washington for 5-day periods for obseruation of detailed relative growth of different parts. Each stipe was marked at intenlals with injected Indian ink and each blade was punched with a series of holes. Measurements of diameter, length, width and thickness were made before and after the 5-day periods. Blades showed a very similar pattern of relative growth rate (R) ovler an 18-fold range of sizes. The maximum local R in length was about 0.2 day⁻¹ and occurred at 6.5% of the distance from the bulb to the tip, declining to 0.01 at half way. Half the linear growth occurred in the proximal one tenth of the blade and 95% within the proximal half: The relative growth rate of the whole blade declined only slightly with increased size and lay between 0.03 and 0.06 day⁻¹ (approx. 3-6% day⁻¹). The linear growth rate therefore increased with blade size, the maximum observed being 14 cm day⁻¹. The maximum relative growth rate in blade width was slower, and sited more distally than that in length. Unless fertile tissue was involved all blade tissue, except that closely adjoining the bulb, became thinner duringgrowth. R in volume reached 0.3 day⁻¹. Presumably because the plants were held near the sea surface stipes grew slowly, with a maximum linear rate of 9 mm day⁻¹. The maximum R in length decreased with stipe length. Bulb R in volume also decreased as size increased, from a maximum of 0.3 day⁻¹.     

三种相思(Acacia)的光合作用与蒸腾作用的研究

本文主要探讨了三种相思的光合作用与蒸腾作用,并观测了不同时间内叶面气孔开启状况。 研究结果表明:三种相思中绢毛相思(A.holosericea)光合速率较高,在生长旺季高峰值可达23.16毫克CO_2·分米~(-2)·时~(-1)。此值较马占相思(A.marjian)高90％;较大叶相思(A.auriculaeformis)高22％。绢毛相思叶子生长速度较抉,叶绿素含量、比叶重也较高。在炎热的夏季,绢毛相思依靠叶片上的绒毛避免太阳光垂直照射,保持气孔开放,使光合作用保持正常。这是对环境的积极适应类型。面大叶相思则是利用增厚叶片角质层和关闭气孔的办法避免大量失水,致使光合作用速率下降。这是对环境的消极忍耐类型,这种类型可更加有效地利用水分。     

猕猴桃嫁接试验

本文报道猕猴桃不同嫁接时期、嫁接方法和不同分类群的砧木试验结果,猕猴桃最适宜的嫁接时期是落叶后至翌年萌芽前,嫁接方法以切接为好,嫁接成活率均在90％以上。同种和同一分类群的砧穗间有良好的亲和力,嫁接均有较高的成活率。不同分类群间嫁接效果较差,如中华猕猴桃桂海4号嫁接于中华猕猴桃砧木上的成活率,生长情况均比嫁接其它分类群为砧的有显著差异。     

螺旋藻品系Z中不同形态藻丝体的生长速率和光合色素比较

The line-shaped filaments Sp-Z(L) were isolated and cultured from Spirulina platensis Sp-Z. The growth rate of Sp-Z(L) was only 64% as much as that of SP-Z when the light intensity was 4000 Lux. The contentS (×10-3 g / g dry weight) of chlorophylls, carotenoids and phycobilins of Sp-Z(L) and Sp-Z were 20.6, 0.343, 5.00 and 24.1 0.297, 4.46, respectively. Moreover, as to the absorption spectra of the three photopigments of SP-Z(L), red shifts were observed. Therefore, after the spiral Sp-Z breeded or changed…     

GROWTH RATES OF ANTARCTIC FUR SEALS AS INDICES OF ENVIRONMENTAL CONDITIONS

The growth rates of Antarctic fur seal ( Arctocephalus gazella ) pups estimated from weighing cross-sections of the population were compared with measured/ inferred changes in the availability of their main prey species, Antarctic krill ( Euphausia superba ) from 1989 to 2000. There was no relationship between growth rate and mass at weaning and there were counter-intuitive indications of higher growth rates in years of low krill availability. Biases reflecting changes in the component of the population available for sampling appear to invalidate the widely held assumption that interannual differences in growth rate can reliably be derived from differences in the slope of a linear relationship based on cross-sectional population samples. A new index was developed, based on the deviation of pup mass at age in each year compared to the multiyear mean, that was not dependent on assumptions of linearity. The indices of growth deviates produced a more logical relationship with other indices of pup development and related more appropriately to variations in prey availability. The potential impact of methodological biases on the interpretation of growth rate suggests that comparisons of growth rates should not rely on assumptions regarding the underlying growth pattern.     

周期型马来丝虫感染期幼虫在人卵巢癌细胞系中的体外培养

周期型马来丝虫感染期幼虫(L_3)在三种含人卵巢粘液性囊腺癌细胞系(OMC_(685))的RPMI1640培养系统中均能蜕皮发育为L_4,幼虫最长存活66天,蜕皮率和完成蜕皮率可分别达57.1％和89.3％。在不含细胞系的培养液中,幼虫最长存活14天,基本上不蜕皮。本实验结果提示OMC_(685)细胞系可能产生某些有利于周期型马来丝虫L_3体外生存和发育的物质。