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1.
Ming Pei You Brandon Lancaster Krishnapillai Sivasithamparam Martin John Barbetti 《Plant and Soil》2008,302(1-2):203-211
In Australia, in the past, pasture legumes were rotated mainly with cereals, but increasingly these rotations now involve
pasture legumes with a wider range of crops, including legumes. This increasing frequency of the leguminous host in the rotation
system may be associated with increased root rots in legumes in the current pasture-crop rotations. The primary aim of this
study was to see whether the pathogenicity on pasture legumes of strains of Rhizoctonia solani sourced from lupins and cereals (common crops in rotation with pastures) is associated with increased incidence of root rots
in pasture legumes in the disease conducive sandy soils of the Mediterranean regions of southern Australia. The second aim
was to determine sources of resistance among newly introduced pasture legumes to R. solani strains originating from rotational crops as this would reduce the impact of disease in the pasture phase. Fifteen pasture
legume genotypes were assessed for their resistance/susceptibility to five different zymogram groups (ZG) of the root rot
pathogen R. solani under glasshouse conditions. Of the R. solani groups tested, ZG1–5 and ZG1–4 (both known to be pathogenic on cereals and legumes) overall, caused the most severe root
disease across the genotypes tested, significantly more than ZG6 (known to be pathogenic on legumes), in turn significantly
>ZG4 (known to be pathogenic on legumes) which in turn was >ZG11 (known to be pathogenic on legumes including tropical species).
Overall, Ornithopus sativus Brot. cvs Cadiz and Margurita, Trifolium michelianum Savi. cvs Paradana and Frontier and T. purpureum Loisel. cv. Electro showed a significant level of resistance to root rot caused by R. solani ZG11 (root disease scores ≤1.2 on a 1–3 scale where 3 = maximum disease severity) while O. sativus cvs Cadiz and Erica showed a significant level of resistance to root rot caused by R. solani ZG4 (scores ≤1.2). O. compressus L. cvs Charano and Frontier, O. sativus cv. Erica, and T. purpureum cv. Electro showed some useful resistance to root rot caused by R. solani ZG6 (scores ≤1.8). This is the first time that cvs Cadiz, Electro, Frontier, Margurita and Paradana have been recognised
for their levels of resistance to root rot caused by R. solani ZG11; and similarly for cvs Cadiz and Erica against ZG4; and for cvs Charano, Erica, and Electro against ZG6. These genotypes
with resistance may also serve as useful sources of resistance in pasture legume breeding programs and also could potentially
be exploited directly into areas where other rotation crops are affected by these R. solani strains. None of the tested genotypes showed useful resistance to R. solani ZG1–4 (scores ≥2.0) or ZG1–5 (scores ≥2.5). This study demonstrates the relative potential of the various R. solani ZG strains, and particularly ZG1–4, ZG1–5, ZG4 and ZG6 to attack legume pastures and pose a significant threat to non-pasture
crop species susceptible to these strains grown in rotation with these pasture legumes. Significantly, the cross-pathogenicity
of these strains could result in the continuous build-up of inoculum of these strains that may seriously affect the productivity
eventually of legumes in all rotations. In particular, when choosing pasture legumes as rotation crops, caution needs to be
exercised so that the cultivars deployed are those with the best resistance to the R. solani ZGs most likely to be prevalent at the location. 相似文献
2.
Household‐level correlates of children's physical activity levels in and across 12 countries 下载免费PDF全文
Deirdre M. Harrington Fiona Gillison Stephanie T. Broyles Jean‐Philippe Chaput Mikael Fogelholm Gang Hu Rebecca Kuriyan Anura Kurpad Allana G. LeBlanc Carol Maher Jose Maia Victor Matsudo Timothy Olds Vincent Onywera Olga L. Sarmiento Martyn Standage Mark S. Tremblay Catrine Tudor‐Locke Pei Zhao Peter T. Katzmarzyk for the ISCOLE Research Group 《Obesity (Silver Spring, Md.)》2016,24(10):2150-2157
3.
Extracellular levels of 5-hydroxytryptamine (5-HT) and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) were measured in the ventral hippocampus of the awake rat using microdialysis. The basal level of 5-HT in hippocampal dialysates was very close to the detection limit of our assay. However, addition of a 5-HT re-uptake blocker, citalopram, to the perfusion medium resulted in a 3-fold rise of 5-HT levels in dialysates and provided a stable baseline. Under these conditions, extracellular levels of 5-HT and 5-HIAA could be measured up to 11 days after dialysis probe implantation. 5-HT measured in dialysate was Ca2+-dependent both 24 h and 7 days after surgery. In comparison K+-induced depolarization caused a 9-fold increase in 5-HT output 24 h after probe implantation and this effect had disappeared 10 days later, although behavioral activation following K+ application was similar 24 h and 11 days after surgery. Systematic administration of
-trytophan had no significant effect on 5-HT but increased 5-HIAA levels by 90%. These results suggest that in the presence of citalopram, 5-HT in hippocampal dialysates is derived from serotonergic neurones. The microdialysis method appears most useful for measurement of extracellular 5-HT 24–72 h after probe implantation. Finally, our data indicate that extracellular 5-HIAA mainly reflects intraneuronal metabolism of 5-HT prior to release. 相似文献
4.
溶液培养小麦幼苗转移至含Cd~(2 )的营养液中,根系乙烯产生较快地增加,约在12h达高峰,然后下降;ACC含量亦呈先升后降的趋势。未和Cd~(2 )溶液直接接触的地上部乙烯亦增加,至36h达高峰,此后急剧下降,而ACG和 MAGC含量持续上升。地上部乙烯的增加,主要是由通过根系运往地上部的镉直接作用的结果,不是根部合成ACG运往地上部后再产生的。电镜观察表明,地上部乙烯产生和ACC含量变化的时间进程,可以与镉进入叶细胞内的部位及其对细胞膜和细胞器的影响相联系。 相似文献
5.
0.5%NaCl抑制愈伤组织生长,处理后期(第21天和28天检测)24kD蛋白含量明显增加。1.0%,2.0%和3.0%NaCl处理的愈伤组织不生长,未检出24kD蛋白增加,但36~42kD蛋白大量增加,并且有随处理的盐浓度增高而增加的趋势。 在1.0%NaCl适应愈伤组织(简称S-1)中24kD蛋白含量明显增加,而36~42 kD蛋白含量下降到对照水平。~(35)S-Met体内标记表明,增加的24kD蛋白是新合成的。S-1回到无盐5代后,仍保持提高的耐盐性和24kD蛋白含量。24kD蛋白含量的增加不受甘露醇胁迫的诱导。初步离心分离的细胞亚组分表明,24kD蛋白主要位于胞质和细胞器膜。在烟草S-1细胞中也发现24kD蛋白含量增加。 相似文献
6.
7.
小麦幼苗根系镉螯合素 总被引:3,自引:0,他引:3
从经Cd~(2+)处理的小麦幼苗根系中分离得到一种镉结合复合物(Cd-BC)。通过SephadexG75,DEAE-52柱层析纯化,鉴定了此复合物性质:(1)紫外吸收光谱在255~265 tim间有一个“肩”,A_(250)/A_(280)>1;(2)在Sephadex G75柱层析上的表观分子量约为10kD,但在SDS-聚丙烯酰胺凝胶电泳上呈现的条带紧接着前沿,分子量非常小;(3)氨基酸组分分析,约90%的氨基酸残基为Glu/Gln,Cys和Gly,三者比例约为4:4:1。结果说明小麦幼苗根系Cd-BC是寡聚肽,是植物镉螯合素(Cd-PCs)的聚合体。 相似文献
8.
凤眼莲无菌苗培养及其克藻效应 总被引:2,自引:0,他引:2
次第选用固体培养基、有机培养溶液和无机培养溶液,通过改善培养条件,从凤眼莲的腋芽培养出生长正常的无菌苗。用生物检测法测试无菌苗对衣藻的克制效应。试验结果表明,在无根际微生物着生的条件下,凤眼莲种植水仍然显示了克藻作用,说明克藻物质是由凤眼莲本身分泌的,不是由根际微生物所产生的。 相似文献
9.
光敏核不育水稻61kD特异性蛋白质的纯化和N—端序列分析 总被引:4,自引:0,他引:4
用制备型聚丙烯酰胺凝胶电泳和制备型等电聚焦纯化了曾报道的光敏核不育水稻 (Oryza sativa)农垦 58S叶绿体的特异性蛋白质 P2 ,得到 SDS- PAGE和等电聚焦 (IEF )纯的 P2。经 SDS- PAGE和 IEF测定 ,该纯蛋白质的分子量是 61 k D,等电点是 5.8。现称 P2为 P61。氨基酸序列分析表明 P61的 N-端氨基酸序列与水稻和大麦叶绿体 ATPaseβ亚基的 N-端氨基酸序列同源。 相似文献
10.
游离氨基酸组分分析表明,水稻培养细胞中谷氨酸和丙氨酸含量很高,占氨基酸总量的40%。高脯氨酸愈伤组织变异体总游离氨基酸含量比原型高45.5%,其中脯氨酸增加最多,其次是雨氨酸和谷氨酸。当NaCl100mmol/L处理时变异体和原型的总氨基酸都增加,而变异体的增量约为原型增量的3倍。蛋白水解氨基酸组分中变异体和原型各氨基酸的相对含量无大差异。蛋白质双向电泳表明,高脯氨酸变异体的蛋白组分发生变化,明显比原型多4个蛋白点。在NaCl100mmol/L处理下原型亦产生53.3kD蛋白,变异体中该蛋白的含量变得更多。盐胁迫下变异体和原型的蛋白质组分变化的差异十分显著,主要表现在蛋白质等电点的变化不同。 相似文献