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11.
12.
Summary The wide diversity of old fruit-tree cultivars originating or introduced into Belgium during the 18
th
and 19
th
centuries was collected as far as feasible over the last fifteen years at the State Plant Pathology Station in Gembloux.
Out of the 2400 accessions now collected, one quarter was recovered from old public collections, and three quarters came from
farms or gardens. The initial intention was to screen the material for disease resistance and other characters of agronomic
interest with a view to using the best cultivars as breeding parents. However, as the collection developed, genetic resources
conservation also became an objectiveper se. The collection presently contains 1150 apple, 850 pear and 300 plum accessions, and smaller numbers of other fruit species.
Each accession is evaluated in an experimental orchard for at least ten years. In view of the growing public interest in old
fruit-tree cultivars, the Plant Pathology Station has for several years been releasing to the nursery trade the better cultivars
emerging from the evaluation, namely nine apple and four plum cultivars, and one peach cultivar. The principal features of
the apple cultivars are presented in this paper. Since 1988, old apple and plum cultivars have been being used at the Station
as parents in a breeding programme, with both controlled and open pollination. In some instances, old apple cultivars have
also been crossed with a modern parent carrying the Vf gene for scab resistance. The preliminary observations on some of these
seedlings are presented. 相似文献
13.
MxIrt1是从苹果属植物小金海棠中克隆出的二价阳离子转运膜蛋白基因。为进一步研究该基
因的功能, 利用MxIrt1基因位于第3和第4跨膜区之间的162 bp片段, 构建了原核表达载体pGEX-MxIrt1,经原核表达、亲和层析、获得GST2MxIRT1融合蛋白, 以融合蛋白为抗原, 制备多克隆抗体, ELISA方法检测抗体效价阳性, 蛋白质印迹检测植物体内总蛋白, 获得与预期大小一致的特异性条带。上述结果表明,表达的目的蛋白可用于免疫组织化学、蛋白质印迹检测。 相似文献
14.
八棱海棠耐盐碱性评价 总被引:1,自引:1,他引:1
为探明八棱海棠的耐盐碱性种质资源价值,以实生苗为试材,采用水培的方法评价了八棱海棠耐盐性和耐碱性.结果表明:1)0.4% NaCI处理30 d时,八棱海棠的盐害指数为51.1,根据耐盐性评价标准判定为中等耐盐型树种;其实生个体间存在广泛的抗性分离现象,极强、强、中、弱和极弱耐盐型植株分别占群体总数的20.6%、23.9%、37.0%、12.0%和6.5%.2)pH9.5碱处理(Na2CO3)30 d时,八棱海棠的碱害指数为16.3,根据耐碱性评价标准判定为极强耐碱型树种;其实生个体间存在广泛的抗性分离现象,极强、强、中、弱和极弱耐碱型植株分别占群体总数的79.1%、15.3%、4.2%、1.4%和0%.八棱海棠中存在极强耐盐型和极强耐碱型植株,是优异的耐盐/碱型种质资源树种. 相似文献
15.
In order to provide the physiological bases for selecting late-germination cultivars that can avoid late frost damage, the very late-germination variety Avrolles (Malus domestica) was used to study the relation between the dynamic changes and balance of endogenous hormones and germination time. The concentrations of endogenous GA3, ABA, IAA, and ZR were determined in buds of Avrolles and Judeline (Malus domestica) from dormancy releasing to germination by capillary electrophoresis. The dynamic changes of endogenous hormones concentration in buds of Avrolles and Judeline were similar; but the magnitude and time of the change were significantly different between the two varieties, especially for GA3. GA3 concentration increased with dormancy releasing, then decreased, and increased again before germination in the two varieties. GA3 concentration in Avrolles was 1.72 times that in Judeline at the first peak, the gap increased to 2.22 times at germination. ZR concentration exhibited a continuous increase trend, but it decreased sharply before germination. ZR accumulation in Avrolles took 36 days longer than in Judeline, the peak value was 44% higher than in Judeline. Before germination, ZR concentration in Avrolles was 2.12 times that in Judeline. The differences between IAA and ABA concentration were relatively small in the two varieties, while the ratios of GA3/ABA and (GA3 + IAA + ZR)/ABA in Avrolles were 2.08 and 1.58 times those in Judeline, respectively. The germination of apple bud was regulated by the endogenous hormones. For the late-germination apple Avrolles, its germination requires higher concentration of GA3 and ZR, which leads to the high ratios of GA3/ABA and (GA3+ IAA+ ZR)/ABA. 相似文献
16.
新疆野苹果花粉活力的研究初报 总被引:4,自引:1,他引:4
以新疆伊犁地区新源县交吾托海野果林原生境内的新疆野苹果不同单株的花粉为试验材料,采用固体培养基法研究了不同保存温度和不同浓度蔗糖对花粉活力的影响。结果表明:花粉常温保存3d以内活力较高,平均萌发率为58%,保存5d以后花粉活力开始明显下降,平均萌发率为37%,保存30d以后平均萌发率仅1%,几乎无活力;花粉4℃保存10d以内具有较高活力,平均萌发率在50%以上,4℃保存130d仍有活力;蔗糖对花粉萌发有明显的促进作用,其中以浓度15%蔗糖较好。单株间花粉活力存在差异。 相似文献
17.
苹果属植物种内和种间无融合生殖能力研究 总被引:4,自引:0,他引:4
】根据去雄套袋的座果率,用方差分析法研究了苹果属7个无融合生殖种类的种内和种间差异。结果表明,种间只有小金海棠与湖北海棠、三叶海棠和丽江山定子的差异极显著。在湖北海棠的4个类型中,南坪湖北海棠、盐源湖北海棠和平邑甜茶与丽江山定子差异显著,其余种间差异均不显著。湖北海棠不同倍性和来源的4个类型间无显著差异。 相似文献
18.
缺锌苹果树有机酸与锌吸收分配的关系 总被引:3,自引:2,他引:3
【目的】研究缺锌大田富士苹果树、苹果幼树和苹果树常用砧木平邑甜茶[Malus hupehensis(Pamp.)Rehd.]幼苗有机酸与锌吸收分配的关系,探讨有机酸影响锌吸收分配的作用机理。【方法】采用盛果期苹果树大田栽培、两年生幼树砂培和平邑甜茶幼苗溶液培养法进行试验。【结果】萌芽期小叶病树根系R0-1.5、R1.5-3、R3-5和R5-15锌和有机酸浓度呈现高于正常树的趋势,盛花期二者的浓度呈现低于正常树的趋势,生理落果期小叶病树根系R0-1.5、R1.5-3、R3-5和R5-15锌浓度显著大于正常树。与正常树相比,有机酸浓度小叶病树R0-1.5和R1.5-3中下降,R3-5和R5-15呈现升高的趋势,小叶病树根系锌吸收利用和有机酸代谢运输节奏发生改变,大田和水培试验发现,苹果树根系有机酸的水平与锌水平有关。缺锌导致盆栽幼树吸收根有机酸含量的升高。与pZn2+10.7相比,水培平邑甜茶pZn2+11.3处理1d,根中锌浓度显著下降,根和茎中草酸和苹果酸的浓度升高了1.09-1.35倍,有机酸向根系的分配比例增加,根系锌吸收速率显著增加;处理20d,平邑甜茶植株中的锌浓度和有机酸浓度及叶中有机酸的分配比例均显著下降。【结论】缺锌改变了苹果根系锌吸收和有机酸的代谢运输节奏,促进了有机酸向地下部的分配,有机酸在促进锌吸收分配方面起重要作用。 相似文献
19.
Shigeki Yoshida Atsushi Kuno Naoto Saito Masakazu Aoyama Isao Kusakabe 《Journal of Wood Science》1998,44(6):457-462
Xylan prepared from culms of kumaizasa (Sasa senanensis Rehd.), a representative species of bamboo grass, was hydrolyzed with-xylanase ofStreptomyces olivaceoviridis E-86. Four arabinoxylo-oligosaccharides and two glucuronoxylo-oligosaccharides were isolated from the enzymatic hydrolysate of the xylan by chromatography on a charcoal column, a Dowex 1-x8 column, a Toyo-pearl HW-40S column, and a LiChrospher 100 NH2 column and on preparative paper chromatography. The results of the structural analyses of the saccharides showed that the isolated oligosaccharides had the structures of 32--l-arabinofuranosyl-xylobiose, 32--l-arabinofuranosyl-xylotriose, 32--[-d-xylopyranosyl-(1 2)-l-arabinofuranosyl]-xylobiose, 33--[-d-xylopyranosyl-(1 2)-l-arabinofuranosyl]-xylotriose, 23--4-O-methyl-d-glucuronosyl-xylotriose, and 23--d-glucuronosyl-xylotriose. From the structural analysis of the oligosaccharides derived from the xylan, kumaizasa xylan was concluded to be a kind of arabinoglucuronoxylan having not only stubs of singlel-arabinose and singled-glucuronic acid but also stubs of disaccharide units such as-d-xylopyranosyl-(1 2)-l-arabinofuranose. 相似文献
20.