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1.
气候变暖背景下秦岭地区≥10℃热量的时空变化 总被引：5，自引：1，他引：4
在全球气候变暖背景下,秦岭地区农业热量的时空变化研究对调整农业种植结构,优化农业产业布局和实现农业的可持续发展具有重要意义。依据1961—2010年秦岭南北71个气象台站的资料,应用气候倾向率、Mann-kendall 突变检验、Moralt 小波分析和ArcGIS 空间插值法,对秦岭南北近50 年来≥10℃的积温、初日、终日和持续日数的变化特征进行分析。结果显示：（1）秦岭南北≥10℃的积温和持续日数均呈增加趋势,初日为提前趋势,终日为推迟趋势;秦岭北部≥10℃初日变化速率低于秦岭南部,秦岭北部≥10℃积温、持续日数和终日的变化速率高于秦岭南部。（2）秦岭北部≥10℃积温、初日、终日和持续日数发生突变的年份分别为1995 年、2003 年、1973 年和2000 年,秦岭南部≥10℃积温、初日、终日和持续日数发生突变的年份分别为2004 年、1995 年、1974 年和1977 年。秦岭南北部≥10℃积温具有明显的20~30年和7~10年的振荡周期。（3）空间上,秦岭地区≥10℃积温的空间变化相似,整体呈增加趋势。 相似文献
2.
临汾市0℃界限温度气候特征变化分析 总被引：3，自引：1，他引：2
在气候变暖背景下,研究临汾市0℃界限温度的变化特征,以期为农业生产提供科学依据。利用临汾市17个地面气象站1981—2014年逐日气温资料,采用线性倾向估计法、滑动平均法、M-K法及距平,对临汾市日平均气温稳定通过0℃的初日、终日、持续日数及积温的时空分布特征进行分析。结果表明：临汾市日平均气温≥0℃初日提前,终日延迟,持续天数呈增加趋势,增长速率为3.9天/10年,初日的提前程度大于终日的延迟程度,临汾市≥0℃的活动积温总体呈增加趋势,增长速率为115.4℃/10年,1993年为突变增长年,2000年之后上升趋势显著性增强;从地域分布看,中部平川地区出现≥0℃初日最早,结束最晚,持续期最长,≥0℃的活动积温最充足,而西山出现≥0℃初日最晚,结束最早,持续期最短,≥0℃的活动积温最少,东山介于平川和西山之间。对于气候变暖给农业生产带来的影响必须进行综合深入的研究。 相似文献
3.
1981—2014年西藏0℃界限温度变化趋势的时空分布 总被引：3，自引：3，他引：0
在气候变暖背景下,分析西藏0℃界限温度变化的时空分布特征,以期合理开发农业气候资源。利用西藏38个站点1981—2014年逐日平均气温资料,采用气候倾向率、M-K和距平等统计方法,对西藏≥0℃初日、终日、持续日数及积温的时空分布特征进行分析。结果表明：近34年西藏平均每10年≥0℃初日提早3.1天、终日推迟1.9天、持续日数延长5.0天和积温增加83.2℃·d,这种变化在低海拔地区表现的更明显。大部分站点≥0℃界限温度都表现初日提早、终日推迟、持续日数延长和积温增多的年代际变化特征。≥0℃初日和积温的突变点出现在21世纪初,终日突变时间早,发生在20世纪80年代后期,而持续日数在90年代中后期出现了突变。 相似文献
4.
在气候变暖背景下,分析高寒地区0 ℃界限温度变化特征,以期为合理开发农牧业气候资源。利用青海省高寒地区贵南县气象局观测的1961—2017年逐日平均气温资料,采用滑动平均法、线性倾向估计、M-K突变分析等方法,对高寒地区贵南县≥0 ℃初日、终日、持续日数及同时期积温变化特征进行分析。结果表明：近57年高寒地区贵南县气温稳定通过0℃的初日呈不显著的提前趋势,终日呈不显著的后延趋势；持续日数以1.48 d.10a-1的气候倾向率呈现显著增多趋势；≥0 ℃的积温以每10年30.2 ℃.d的气候倾向率呈现极显著的升高趋势。气温稳定通过0℃的初日、终日未发生突变；持续日数在1985年发生了由少到多的突变；积温在1994年发生由少到多突变。 相似文献
5.
陕西宝鸡市近50年0℃界限温度气候特征变化分析 总被引：2，自引：1，他引：1
为了研究气候变暖背景下0℃界限温度的变化特征,分析陕西宝鸡市1961—2010年日平均气温稳定通过0℃的初日、终日、间隔日数及其积温、降水量的变化特征。结果表明：陕西宝鸡市日平均气温≥0℃的初日呈显著提早趋势,终日呈波动推迟趋势。初终日之间间隔日数显著增加。≥0℃期间的积温以73.86℃?a/10 a显著增加,降水量以13.706 mm/10 a缓慢减少。积温年代际波动增加,冷暖交替频繁。气候变化影响冬小麦种植品种特性转变,适宜播种期推迟,主要发育期提前,有效生长期明显延长,对提高作物产量有重要意义。 相似文献
6.
气侯变暖显著改变了内蒙古地区的热量资源,了解该地区的热量资源变化可为作物生产及空间布局提供一定的研究基础。本文基于1959—2018年50个气象站点的逐日平均气温,采用五日滑动平均法探讨了内蒙古地区≥0℃和≥10℃初终日、持续天数以及积温的时空分布特征。结果表明：（1）内蒙古地区≥0℃和≥10℃平均初日分别为3月29日和5月5日,≥0℃和≥10℃初日呈提前趋势。≥0℃和≥10℃平均终日分别为10月28日和9月24日。（2）初日提前和终日推迟显著增加了内蒙古地区的积温和持续天数,积温和持续天数在空间分布上相似,东西部差异较大,其中≥0℃积温在1874~4433℃之间,≥10℃积温在1360~4024℃之间,≥0℃持续天数在168~246天之间,≥10℃持续天数在89~180天之间。≥0℃和≥10℃积温和持续天数呈增加趋势。（3）≥0℃和≥10℃初日与经纬度呈正相关关系,终日、积温和持续天数与经纬度成负相关关系。（4）初终日、持续天数以及积温突变日期主要集中在1991—1996年之间。 相似文献
7.
为了给贵南地区合理利用气候资源及农业生产布局提供科学依据,笔者利用青海省贵南县气象局观测的1961—2017年逐日平均气温资料,使用线性趋势分析、累积距平、t检验法等方法,分析贵南县1961—2017年日平均气温稳定通过10 ℃的初日、终日、持续日数及同时期积温的变化特征。结果表明：1961—2017年贵南县气温稳定通过10 ℃的初日提前、终日推迟、持续日数延长、积温增加的现象,其倾向率分别为3.2 d.10a-1、1.1 d.10a-1、4.8 d.10a-1和65.6 (℃.d).10a-1。气温稳定通过10℃的初日在1994年发生提前突变、终日在1988年发生推迟突变;持续日数和积温均在1993年发生了由少到多的突变。 相似文献
8.
为了解气候变化对山西省农作物种植的影响，本文基于1961—2016年气温格点数据，利用Mann-Kendall趋势/突变检验、变异系数和多元回归插值法对山西省≥5℃、≥10℃有效积温进行分析。结果表明：（1）1961—2016年≥5℃和≥10℃有效积温均呈明显的升高趋势，有效积温升温较快的区域主要分布在山西省北部和地势较低的谷地、盆地，由东北向西南呈带状分布。（2）≥5℃和≥10℃有效积温在空间分布上表现出自南向北逐渐减少的趋势，且其在空间分布上受海拔影响较大。≥5℃有效积温在适宜作物生长的积温范围分布面积更大，在大多数地区更适宜喜凉作物的种植。（3）≥5℃和≥10℃有效积温均在1997年发生突变，突变后积温界限北界向高纬和高海拔地区移动。（4）≥5℃和≥10℃有效积温初始日期多呈提前趋势，结束日期多为推后趋势；积温持续日期增长，这种趋势在山西省南部及河谷、盆地地区更为明显；有效积温初始日期变异系数均由东北向西南逐渐增大，汾河谷地有效积温初始日期变率较大；结束日期的变异系数较小，分布更为稳定。 相似文献
9.
为了有效防御和减轻霜冻灾害对高寒贵南地区农牧业生产的影响,为合理开展农牧业气候区划提供可靠依据。利用青海省高寒地区贵南县气象局观测的1961—2017年逐日最低气温、平均气温资料,采用线性倾向估计、M-K突变分析等方法,对高寒地区贵南县霜冻初日、终日、无霜期及同时期积温变化特征进行分析。结果表明：近57年高寒地区贵南县≤0 ℃霜冻的终日呈极显著的提前趋势,初日呈显著的后延趋势,终日提前的幅度大于初日后延的幅度；无霜期呈现极显著延长趋势,无霜期积温呈现极显著的升高趋势。霜冻终日在1972年发生了提前突变,霜冻初日和无霜期在1970年发生了延迟突变,无霜期积温在1977年发生了升高突变。 相似文献
10.
利用西藏“一江两河”流域9个气象站点1980—2020年逐日平均气温资料,采用线性回归、Mann-Kendall非参数检验、相关分析等方法,分析了研究期内“一江两河”主要农区负积温的时空分布特征及其与气温、积雪和冻土的关系。结果表明：“一江两河”农区负积温总体上呈自西向东递减分布,并随海拔升高而降低。该农区负积温初日推迟率为3.11 d/10 a,终日平均10年提早2.53天,持续日数缩短率为6.03 d/10 a,负积温以24.93(℃·d)/10 a的速度显著升高。在10年际变化尺度上,负积温表现为逐年代升高的变化特征,其中1980s—1990s偏低,2000s—2010s明显偏高。进入21世纪后,负积温初日推迟、终日提早、持续日数缩短和积温升高的年代际变化特征尤为明显。M-K检验显示,负积温终日突变时间较早,为1993年;初日和持续日数均发生在1996年,负积温出现在1995年;突变后负积温初日推迟9天、终日提早6天、持续日数缩短17天、积温减少68.6℃·d。负积温升高与冬季平均气温上升、积雪日数减少和冻土退化具有较好的一致性。负积温对农业生产的影响有利有弊。 相似文献
11.
Jens Jensen 《Euphytica》1979,28(1):47-56
Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans. 相似文献
12.
G. H. Kroon 《Euphytica》1994,76(1-2):125-125
Summary
K x vadensis is a hybrid of K. blossfeldiana and K. marmorata obtained after doubling the number of chromosomes. 相似文献
13.
Hongyan WEI Jian ZHOU Jinguang LU Jingzheng SONG Qiongxi YU Zhihong JIANG 《Medicinal Plant》2019,(6):27-29
[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol... 相似文献
14.
Summary Avoidance of rust fungi that was based on poor appressorium induction was previously found in Hordeum chilense. In the present study 95 accessions of Triticeae were screened for avoidance of Puccinia hordei. The percentage of appressorium formation per germinated spore ranged from 6 to 90%. On none of the 41 accessions of Aegilops, Agropyron, Elymus, Secale, Thinopyrum or Triticum studied was the rate of appressorium formation lower than 25%. Lower rates of appressorium formation were, however, found on accessions of wild barley species Hordeum brachyantherum, H. marinum, H. parodii and H. secalinum. Its implications in cereal breeding are discussed. 相似文献
15.
D. A. Bond G. J. Jellis G. G. Rowland J. Le Guen L. D. Robertson S. A. Khalil L. Li-Juan 《Euphytica》1993,73(1-2):151-166
Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses. 相似文献
16.
Chunli TANG Fengxian ZHAO Hongxia CHEN Jiabao MA Jiangcun WEI Meiyan QIU Zhen XIE 《Medicinal Plant》2019,(6):60-65
[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination... 相似文献
17.
E. Keep 《Euphytica》1986,35(3):843-855
Summary Cytoplasmic male sterility (cms) is described in the F1 hybrids Ribes × carrierei (R. glutinosum albidum × R. nigrum) and R. sanguineum × R. nigrum. In backcrosses to R. nigrum, progenies with R. glutinosum cytoplasm were either all male sterile, or segregated for full male fertility (F) and complete (S) and partial (I) male sterility. Ratios of F:I+S suggested that two linked genes controlled cms, F plants being dominant for one (Rf
1) and recessive for the other (Rf
2).Segregation for cms in relation to three linded genes, Ce (resistance to the gall mite, Cecidophyopsis ribes), Sph
3(resistance to American gooseberry mildew, Sphaerotheca mors-uvae) and Lf
1(one of two dominant additive genes controlling early season leafing out) indicated that Rf
1and Rf
2were in this linkage group. The gene order and approximate crossover values appeared to be: % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXafv3ySLgzGmvETj2BSbqef0uAJj3BZ9Mz0bYu% H52CGmvzYLMzaerbd9wDYLwzYbItLDharqqr1ngBPrgifHhDYfgasa% acOqpw0xe9v8qqaqFD0xXdHaVhbbf9v8qqaqFr0xc9pk0xbba9q8Wq% Ffea0-yr0RYxir-Jbba9q8aq0-yq-He9q8qqQ8frFve9Fve9Ff0dme% aabaqaciGacaGaamqadaabaeaafaaakeaacaWGdbGaamyzamaamaaa% baGaaiiiaiaacccacaGGWaGaaiOlaiaacgdacaGG0aGaaiiiaiaacc% caaaGaaiiiaiaacccacaGGGaGaamOuaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaaccdacaGGUaGaaiOmaiaacs% dacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaaaacaWGsbGaamOzaSGa% aGOmaOWaaWaaaeaacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccaaaGaamitaiaadAgaliaaigdakmaamaaa% baGaaiiiaiaacccacaGGGaGaaiiiaiaacccacaGGGaGaaiiiaiaacc% cacaGGGaGaaiiiaiaacccacaGGGaaaaiaadofacaWGWbGaamiAaSGa% aG4maaaa!6E4D!\[Ce\underline { 0.14 } Rf1\underline { 0.24 } Rf2\underline { } Lf1\underline { } Sph3\]. Crossover values of 0.36 for Ce-Lf
1, and 0.15 for Lf
1-Sph
3were estimated from the relative mean differences in season of leafing out between seedlings dominant and recessive for Ce and Sph
3.It is suggested that competitive disadvantage of lf
1-carrying gametes and/or zygotes at low temperatures may be implicated in the almost invariable deficit of plants dominant for the closely linked mildew resistance allele Sph
3. Poor performance of lf
1- (and possibly lf
2-) carrying gametes and young zygotes during periods of low temperature at flowering might also account for the liability of some late season cultivars and selections to premature fruit drop (running off). 相似文献
18.
[Objectives] To determine the optimum extraction technology for total phenols of leaves in Acanthopanax giraldii Harms.[Methods]The single factor test and ortho... 相似文献
19.
Summary Apple and pear pollen was irradiated with doses of 0, 50, 100, 250 and 500 krad (gamma rays) and stored at 4°C and 0–10% r.h. From the in-vitro germination percentages an average LD 50 dose of about 220 krad was estimated. For both irradiated and untreated pollen a close and corresponding lineair relationship existed between germination percentage and pollen tube growth.Irradiated pollen was much more sensitive to dry storage conditions than untreated pollen, resulting in less germination and more bursting. Apparently, irradiation caused the pollen cell membrane to lose its flexibility faster than normal. Rehydration of dry-stored, irradiated pollen in water-saturated air restored germination percentages up to their initial levels. The importance of this procedure in germination trials is stressed. 相似文献
20.
Parasitic angiosperms cause great losses in many important crops under different climatic conditions and soil types. The most widespread and important parasitic angiosperms belong to the genera Orobanche, Striga, and Cuscuta. The most important economical hosts belong to the Poaceae, Asteraceae, Solanaceae, Cucurbitaceae, and Fabaceae. Although some resistant cultivars have been identified in several crops, great gaps exist in our knowledge of the parasites and the genetic basis of the resistance, as well as the availability of in vitro screening techniques. Screening techniques are based on reactions of the host root or foliage. In vitro or greenhouse screening methods based on the reaction of root and/or foliar tissues are usually superior to field screenings and can be used with many species. To utilize them in plant breeding, it is necessary to demonstrate a strong correlation between in vitro and field data. The correlation should be calculated for every environment in which selection is practiced. Using biochemical analysis as a screening technique has had limited success. The reason seems to be the complex host-parasite interactions which lead to germination, rhizotropism, infection, and growth of the parasite. Germination results from chemicals produced by the host. Resistance is only available in a small group of crops. Resistance has been found in cultivated, primitive and wild forms, depending on the specific host-parasite system. An additional problem is the existence of pathotypes in the parasites. Inheritance of host resistance is usually polygenic and its transfer is slow and tedious. Molecular techniques have yet to be used to locate resistance to parasitic angiosperms. While intensifying the search for genes that control resistance to specific parasitic angiosperms, the best strategy to screen for resistance is to improve the already existing in vitro or greenhouse screening techniques. 相似文献