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81.
Wajirou Suzuki 《Ecological Research》1997,12(2):167-174
To clarify the adaptive significance of seed dormancy, the effects of burial duration were examined for two deciduousRubus species:Rubus palmatus var.coptophyllus andRubus parvifolius, which are found mainly in relatively stable, shaded sites and disturbed sites, respectively. In early summer, newly ripened
seeds were buried under litter on the soil surface in a pine forest, and germination tests were carried out for the seeds
retrieved from the soil litter after 0 (not buried), 1, 2, 3, 5 and 8 or 9 months of burial. In general, the germination percentages
increased and light requirements for germination decreased with increased burial duration. The percentage of seeds germinated
with alternating temperatures in darkness also increased with increasing burial duration for both species. After 8 or 9 months
of burial (corresponding to the next germination season in the field), the percentage of non-dormant seeds (including germination
under alternating temperatures in the dark) was about 80% and 40% forR. palmatus var.coptophyllus andR. parvifolius, respectively. These seed dormancy traits of the twoRubus species may explain the differences in germination strategy in their habitats:R. palmatus var.coptophyllus seems to have adapted to the seasonal occurrence of favorable growing conditions after the dormancy breakage, whileR. parvifolius seems to have adapted to favorable conditions created by temporally unpredictable disturbances. 相似文献
82.
悬钩子属田间基因库的建立与维护 总被引:8,自引:0,他引:8
江苏省植物研究所、中国科学院植物研究所在进行了7个省悬钩子属(RubusL.)种质资源调查的基础上,1993年获得国家自然科学基金资助,在南京建立了我国第一个悬钩子属田间基因库,开展了是钩子属种质资源评价的研究。本文论述了悬钩子植物在植株大小、地上部寿命和直立性、前蘖发生、顶端生根特性以及生态适应性等方面的遗传多样性及与此相应的田间基因库建设和维护措施。 相似文献
83.
Genomic characterisation and the detection of raspberry chromatin in polyploid Rubus 总被引:3,自引:0,他引:3
K. Y. Lim I. J. Leitch A. R. Leitch 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1998,97(7):1027-1033
This paper reports genomic in situ hybridization (GISH) and fluorescent in situ hybridization (FISH) data for chromosomes
of raspberry (Rubus idaeus 2n=2x=14), blackberry (Rubus aggregate, subgenus Eubatus. 2n=2–12x=14–84) and their allopolyploid derivatives used in fruit breeding programmes. GISH was used to discriminate labelled
chromosomes of raspberry origin from those of blackberry origin in allopolyploid hybrid plants. The raspberry chromosomes
were labelled by GISH at their centromeres, and 1 chromosome was also labelled over the short arm. In one allopentaploid plant
a chromosome carried a terminal signal. Karyotype analysis indicated that this is a blackberry chromosome carrying a raspberry
translocation. GISH analysis of an aneuoctaploid blackberry cv ‘Aurora’ (2n=8x=58) showed that both whole and translocated
raspberry chromosomes were present. The basic Rubus genome has one ribosomal DNA (rDNA) locus, and in all but one case all levels of ploidy had the expected multiples of rDNA
loci. Interestingly, in the blackberry cv ‘Aurora’, there were only six sites, two less than might be predicted from its aneuoctaploid
chromosome number. Our results highlight the potential of GISH and FISH for genomic designation, physical mapping and introgression
studies in Rosaceous fruit crops.
Received: 20 February 1998 / Accepted: 12 May 1998 相似文献
84.
Effect of Application Timing of Oxamyl in Nonbearing Raspberry for Pratylenchus penetrans Management
In 2012, the Washington raspberry (Rubus idaeus) industry received a special local needs (SLN) 24(c) label to apply Vydate L® (active ingredient oxamyl) to nonbearing raspberry for the management of Pratylenchus penetrans. This is a new use pattern of this nematicide for raspberry growers; therefore, research was conducted to identify the optimum spring application timing of oxamyl for the suppression of P. penetrans. Three on-farm trials in each of 2012 and 2013 were established in Washington in newly planted raspberry trials on a range of varieties. Oxamyl was applied twice in April (2013 only), May, and June, and these treatments were compared to each other as well as a nontreated control. Population densities of P. penetrans were determined in the fall and spring postoxamyl applications for at least 1.5 years. Plant vigor was also evaluated in the trials. Combined results from 2012 and 2013 trials indicated that application timing in the spring was not critical. Oxamyl application reduced root P. penetrans population densities in all six trials. Reductions in P. penetrans population densities in roots of oxamyl-treated plants, regardless of application timing, ranged from 62% to 99% of densities in nontreated controls. Phytotoxicity to newly planted raspberry was never observed in any of the trials. A nonbearing application of oxamyl is an important addition to current control methods used to manage P. penetrans in raspberry in Washington. 相似文献
85.
本文在裂叶悬钩子的叶外植体培养不定芽发生的基础上,利用圆盘聚丙烯酰胺凝胶电泳技术,研究了其细胞分化过程中过氧化物酶同工酶的变化。实验指出:在有6-BA或2.4-D与NAA组合的培养条件下,随着培养时间和分化进程不同,过氧化物酶同工酶有变化,谱带由4条增加到8条,酶的活力分别由△0.24 OD/min提高到△1.82OD/min和△1.90 OD/min。在无外源激素条件下,过氧化物酶同工酶的变化不大,酶的活力也低,因而,叶外植体组织细胞也不能分化成植株。本文还从分子水平上探讨了酶和基因与细胞分化的关系。 相似文献
86.
通过观察箱和野外挖掘调查,对蓬 (Rubus hirsutus Thunb.)根系自然分布及生长发育特性进行了连续两年的观察记载。结果表明:其根系自然分布水平幅度为1.4×1.5m~2,垂直深度一般小于50cm,集中分布于10~25cm深的土层中;净增根数及根系总长度在5月底达最高峰,以后渐趋减少,根系最活跃期20cm土层深处土温为21℃,此时正是结果量最大的时期,地上部分高生长略滞后于根系生长,两者表现出同步协调性。 相似文献
87.
The ATP- and pyrophosphate-dependent proton pumps from tonoplast-enriched vesicles prepared from Rubus hispidus cell cultures were solubilized in the presence of polyoxyethylene(9,10)p-t-octylphenol (Triton X-100) and reconstituted into liposomes of soybean phospholipids, using Bio-Beads SM-2 to remove the detergent. The specific activity of the two pumps was greatly increased by the solubilization-reconstitution procedure. Identical characteristics were found for pyrophosphate-dependent proton transport in native and reconstituted vesicles. On the other hand, the ATP-dependent proton transport of the reconstituted vesicles was no longer inhibited by KNO3. 相似文献
88.
Jimmy Klick Jana C. Lee James R. Hagler Denny J. Bruck Wei Q. Yang 《Entomologia Experimentalis et Applicata》2014,152(1):31-41
Drosophila suzukii Matsumura (Diptera: Drosophilidae) utilizes ‘Himalaya’ blackberry, Rubus armeniacus Focke (Rosaceae), as a host and may invade berry and stone fruit crops from field margins containing this invasive weed. Laboratory and semi‐field studies were conducted to determine (1) the persistence of protein marks including 10% chicken egg whites (egg albumin protein), 20% bovine milk (milk casein protein), and 20% soy milk (soy trypsin inhibitor protein) on topically sprayed D. suzukii, (2) protein retention on blackberry leaves, and (3) D. suzukii acquisition of protein after exposure to marked blackberry leaves for up to 14 days after application. All flies and leaves were assayed for the presence of the protein marks using protein‐specific enzyme‐linked immunosorbent assays. Egg albumin, milk casein, and soy trypsin proteins persisted on 94, 49, and 25% of the topically marked D. suzukii, respectively, throughout the 14‐day study period. Egg albumin was retained on 100% of treated leaves for 14 days, regardless of environmental conditions. At least 50% of flies exposed residually to egg albumin‐treated leaves were marked for 3 days, regardless of exposure time and environmental conditions. However, increasing fly exposure time to treated leaves in April and June appeared to improve protein mark acquisition. Acquisition of protein by flies from treated leaves for milk casein was inconsistent, and poor for soy trypsin, despite detectable levels on treated leaves. Egg albumin had the longest and most consistent persistence on flies, leaves, and flies exposed to leaves in laboratory and semi‐field studies, under a variety of environmental conditions and exposure times. 相似文献
89.
牛叠肚幼苗对盐碱胁迫的生理响应及其耐盐阈值 总被引:1,自引:0,他引:1
以盆栽牛叠肚组培苗为试材,比较研究了不同浓度中性盐(NaCl、Na2SO4)和碱性盐(NaHCO3、Na2CO3)胁迫对其生长和生理指标的影响。结果显示:(1)牛叠肚幼苗生长在碱性盐(NaHCO3、Na2CO3)处理下表现出"低促高抑"现象,而在中性盐(NaCl、Na2SO4)处理下均受到不同程度的抑制。(2)随着盐碱胁迫浓度的升高,牛叠肚叶片的相对电导率呈增加趋势,丙二醛(MDA)积累波动变化;Na2SO4和NaHCO3处理下二者之间的变化趋势相似,而NaCl和Na2CO3处理下二者之间变化趋势则不同。(3)牛叠肚叶片中超氧化物歧化酶(SOD)活性随胁迫浓度增加先升高后下降,而过氧化物酶(POD)活性呈先下降后升高趋势,说明牛叠肚主要通过SOD和POD的互补作用来降低氧化伤害。(4)以相对株高生长量下降50%为标准,求得牛叠肚幼苗对NaCl、Na2SO4、NaHCO3、Na2CO34种单盐的耐受阈值分别为85.18(0.50%,W/V)、40.77(0.58%,W/V)、171.00(1.44%,W/V)、114.20(1.21%,W/V)mmol·L-1。研究表明,各盐碱胁迫使牛叠肚幼苗的生长受到不同程度的抑制,但其在一定浓度范围内通过提高抗氧化酶(SOD、POD)活性来减轻盐碱伤害,维持植株的正常生理代谢;牛叠肚幼苗对碱性盐(NaHCO3、Na2CO3)的耐受能力强于中性盐(NaCl、Na2SO4)。 相似文献
90.
It is often argued that the benefit of eradication of an invasive species—a one-off injection of funds and the problem is solved—far outweighs the cost of a perennial control program. Furthermore, these are very attractive projects for funding agencies as outcomes are clear and easy to assess. Galapagos is in the early stage of the invasion process, with most alien species not yet naturalized and still restricted to gardens and farms. These species should be easy targets for early and cost-effective eradication projects, which would prevent many future problems. We review 30 plant eradication projects covering 23 potentially invasive species with limited distributions on four of the Galapagos Islands. Of the 30 projects, only four were successful: these were all less than 1 ha in net area, on land with a single owner and did not have persistent seed banks. Of the other 26 projects, most failed due to a lack of support from institutions that did not offer continuity of resources, from land owners who denied permission to carry out the work or from being too ambitious. As a result of these problems, 64.3% of the funding secured for the program was spent on discontinued projects. We highlight lessons learned to inform plant eradication programs in the future. 相似文献