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1.
内蒙古草原不同植物种群土壤化学元素特征   总被引：4，自引：0，他引：4  
对内蒙古温带典型草原冷蒿（Artemisia frigida）、星毛委陵菜（Potentilla acaulis）、羊草（Leymus chinensis）、木地肤（Kochia prostrata）和小叶锦码儿（Caragana mierophylla）种群土壤无机氮、微生物量氮、全氮、有机碳、净氮矿化速率和pH等特性进行了系统研究，、结果表明，不同植物种群土壤pH值和全N含量3个取样期均以羊草最高，其次为星毛委陵菜，小叶锦鸡儿种群最低。除冷蒿与术地肤种群问外，其他种群间土壤pH值和全N含量均达到显著性差异（P〈0．05）。羊草种群土壤无机N含量最高，其次依次为冷蒿种群、小叶锦鸡儿种群、木地肤种群和星毛委陵菜种群。各植物种群间土壤无机N含量均达到了显著性差异（P〈0．05）。不同植物种群土壤微生物量氮（MBN）3个取样期均以小叶锦鸡儿最高，其次依次为羊草种群、冷蒿种群、木地肤种群和星毛委陵菜种群，各种群间差异显著（P〈0．05）。3个培养期均以羊草种群土壤净氮矿化速率最高，其次依次为冷蒿、星毛委陵菜、木地肤和小叶锦鸡儿，各种群间均达到了显著差异（P〈0．05）。土壤净氮矿化速率与植物种群土壤pH、温度和C：N分别存在显著的正相关和负相关关系（P〈0．05）。3个取样期土壤有机碳含量均以小叶锦鸡儿种群最高，其次为羊草种群，星毛委陵菜种群最低。除冷蒿种群与木地肤种群间土壤有机碳含量差异不显著（P〉0．05）外，其他各植物种群间土壤有机碳含量均达到了显著性差异（P〈0．05）。这些变化特征说明，随着草地退化和灌丛化，土壤养分呈降低趋势，尤其是有效养分变化更加明显。  相似文献   

2.
以2年生高羊茅（Festuca arundinacea Shreb．）为供试材料,采用移植盆栽方法,不同浓度硝酸盐（NO3^- -N）和氨盐（NH4^＋-N）溶液供给为处理,研究不同形态氮素对高羊茅叶片活性铁含量,叶绿素合成及叶片氮、磷、钾含量的影响,为进一步优化草坪施肥方案和改善观赏品质提供理论依据。研究表明：（1）NH4^＋-N有利于植物叶片对Fe的吸收,叶片内活性铁含量高;NO3^--N不利于叶片对Fe的吸收．活性铁含量偏低。（2）不同形态氮浓度从1-8mmol／L范围内,随着氮浓度的增加叶绿素含量提高,在12mmol／L浓度时叶绿素含量均下降。（3）随两种形态氮素浓度增加,叶片氮、磷的含量随之增加,施用NH4^＋-N叶片内钾的吸收和分配受到抑制。NH4^-N有利于植株对活性铁的吸收和叶绿体的合成;NO3-N有利于植株对营养元素的吸收。  相似文献   

3.
为研究日粮中不同比例小麦替代玉米对奶牛氮代谢参数的影响,选择8头泌乳天数为84±17 d,体重为569±47 kg的经产中国荷斯坦奶牛作为试验动物,采用重复4×4拉丁方设计,分别饲喂含不同比例粉碎小麦（ GW）和粉碎玉米（GC）的日粮,4个处理组分别为（DM基础）：W0组（0％GW＋27．9％GC）,W9．6组（9．6％GW＋19．2％GC）,W19．2组（19．2％GW＋9．6％GC）和W28．8组（28．8％GW＋0％GC）。结果表明：奶牛的产奶量、乳蛋白率和乳蛋白产量未受影响;随着日粮中小麦比例的增加,奶牛的干物质采食量（DMI）呈二次曲线增加趋势（P＝0．07）,牛奶尿素氮（MUN）浓度线性增加（P＜0．01）,且W28．8组显著高于W0和W19．2组（P＜0．01）;粪氮排出量未受日粮影响,尿氮排出量呈线性增加趋势（P＝0．08）;尿氮（P＝0．02）和总排出氮（粪氮＋尿氮）（P＝0．05）占食入氮的比例呈二次曲线降低;尿素氮产量（P＜0．01）及其占总尿氮的比例（P＝0．03）线性增加,且W19．2和W28．8组的尿素氮产量显著高于（P＝0．01）其他2组;尿中尿囊素（P＝0．05）和总嘌呤（P＝0．09）产量呈线性降低趋势,W9．6组的微生物氮产量显著（P＝0．02）高于W28．8组。结果提示：泌乳盛期奶牛日粮中用9．6％的粉碎小麦替代玉米效果最佳,高比例的小麦替代玉米（ W28．8组）时能够增加尿氮及奶和尿中尿素氮的排出量,降低微生物氮的合成。  相似文献   

4.
生长调节剂2,4-D灌施对烤烟上部叶常规化学成分的影响   总被引：1，自引：3，他引：1  
以代表性烤烟品种云烟87为材料，用不同浓度的2，4-D水溶液对打顶后的烟株进行了灌施处理，采用连续流动分析法及火焰光度法测定上部叶初烤烟的常规化学成分含量。结论是：（1）0—100mL／L2，4-D灌施，浓度与烤烟上部叶烟碱含量呈极显著的负相关（P〈0．01），与上部叶的糖碱比值呈极显著的正相关（P〈0．01），与其钾含量呈显著的正相关（P〈0．05）；（2）2，4-D灌施可以显著降低烤烟上部叶的烟碱含量、提高上部叶糖碱比值及钾含量；（3）2，4-D灌施对烤烟上部叶的还原糖及氯含量均无明显影响；（4）2，4-D灌施可提高烤烟上部叶常规化学成分的协调性，从而提高上部叶的可用性。  相似文献   

5.
不同铜源对西门塔尔牛瘤胃发酵和尿嘌呤衍生物的影响   总被引：1，自引：0，他引：1  
选用5头体重420±15．2kg、年龄2．5岁、装有永久性瘤胃瘘管的中国西门塔尔牛阉牛，采用（长X宽）5X5拉丁方设计，以风干玉米秸秆和混合精料为基础日粮，分别在基础日粮风干物质基础上添加硫酸铜、富铜酵母、赖氨酸铜、蛋氨酸铜和包被铜（8mg铜／kg日粮），研究不同铜源对瘤胃发酵和尿嘌呤衍生物浓度的影响。结果表明：不同铜源对pH值、乙酸、丙酸、丁酸和乙酸／丙酸无显著影响，富铜酵母、赖氨酸铜、蛋氨酸铜和包被铜组总酸和氨态氮浓度显著低于硫酸铜组（P〈0．05）。不同铜源对尿酸含量无显著影响，富铜酵母、赖氨酸铜、蛋氨酸铜和包被铜组尿囊素和尿嘌呤衍生物含量显著高于硫酸铜组（P〈0．05）。根据研究结果初步判定，蛋氨酸铜和包被铜是牛较好的饲料铜源，富铜酵母和赖氨酸铜次之。  相似文献   

6.
探讨小花棘豆黄酮对绵羊瘤胃微生物数量的影响,为小花棘豆的综合利用提供参考。将12只和田羊随机分为4组,即对照组、试验Ⅰ组、试验Ⅱ组和试验Ⅲ组。试验组分别按10,30,50 mg／kg的剂量饲喂小花棘豆黄酮,试验持续35 d。试验前及试验后每隔7 d取瘤胃液,检测瘤胃液中微生物数量的变化。结果显示,与对照相比,试验羊瘤胃液中总细菌数均有不同程度的升高,其中从第21天开始试验Ⅰ组和试验Ⅱ组瘤胃液总细菌数均显著高于对照（P＜0．05）,但试验Ⅲ组与对照差异不显著（P＞0．05）;所有试验羊瘤胃液中厌氧真菌数和瘤胃原虫数均无明显变化,试验Ⅰ组和试验Ⅱ组瘤胃液纤维素降解菌数量无明显变化,试验Ⅲ组可降低白色瘤胃球和黄化瘤胃球菌数,但与对照差异不显著（P＞0．05）。结果表明,在日粮中适量添加小花棘豆黄酮对绵羊瘤胃微生物数量无不良影响。  相似文献   

7.
UV-B辐射增强下施氮对大麦土壤微生物量碳、氮的影响   总被引：2，自引：0，他引：2  
通过田间试验,研究了UV-B辐射增强下不同施氮量对大麦土壤微生物量碳、氮的影响。UV-B辐射设对照（CK）和增强（E）2水平,施氮量设高、中、低3水平,分别为30、150和300 kg N/ha。结果表明：与对照相比,无论施氮量高低,UV-B辐射增强对非根际土壤微生物量碳、氮含量有促进作用;除低氮外,UV-B辐射增强对根际土壤微生物量碳、氮含量有抑制作用。在一定UV-B辐射强度下,高施氮量会降低根际土壤微生物量氮和非根际土微生物量碳、氮含量。  相似文献   

8.
为了明确Crylab毒蛋白是否对亚洲玉米螟具有控害作用．采用实验种群生命表的方法。研究了CrylAb毒蛋白对亚洲玉米螟的生长发育和种群增长的影响。结果表明．亚洲玉米螟在各个发育阶段对高浓度（50μg／mL）的CrylAb毒蛋白敏感，而对低浓度（0．1μg／mL）的CrylAh毒蛋白不敏感．10．0pμg／mLCrylAb毒蛋白处理的亚洲玉米螟幼虫历期显著低于对照和其它处理（P〈0．05）。50．0μg/mLCrylAb毒蛋白处理的亚洲玉米螟雌成虫产卵前期、单雌产卵量和雌成虫寿命均显著低于对照（P〈0．05）。1．0μg／mLCrylAb毒蛋白处理的亚洲玉米螟蛹重显著低于对照（P〈0．05）。50．0、10．0、1．0、0．1μg／mLCrylAb毒蛋白的人工饲料处理的亚洲玉米螟净增长率显著低于对照（P〈0．05）。而0．1μg／mLCrylAb毒蛋白处理的净增长率和世代平均周期均显著短于对照（P〈0．05）．．结果表明．CrylAb毒蛋白对亚洲玉米螟的种群增长有一定影响．且对亚洲玉米螟具有一定的控制作用。  相似文献   

9.
为揭示施肥对甜菜生长季节黑土氮形态动态变化规律,采用不同施肥处理研究甜菜生长季（5—9 月）东北黑土0~90 cm无机氮（铵态氮和硝态氮）和有机氮各组分（酸解总氮、氨态氮、氨基糖态氮、氨基酸态氮、酸解未知态氮及非酸解态氮）时空动态变异特征。结果表明,施肥处理在甜菜生育前期（5—7 月）对铵态氮和硝态氮时空变化有显著影响。土壤硝态氮主要分布在0~50 cm 且含量高于铵态氮,相比无肥有作物对照(CK2),施氮肥处理在甜菜幼苗期增加了土壤0~30 cm铵态氮和硝态氮含量,同时增加块根糖分增长期（7 月）土壤0~70 cm硝态氮的消耗。与不施氮相比,施氮肥可以增加0~30 cm土壤酸解总氮、氨态氮和氨基酸态氮的含量。土壤酸解总氮、氨态氮和氨基酸态氮含量在0~90 cm呈明显递减的空间梯度变化,但施氮肥处理可以平衡0~50 cm土壤氨基酸含量;土壤氨态氮随着甜菜生育时期进行呈先增加后下降的变化规律;土壤氨基糖态氮含量时空变化不显著;土壤未知态氮含量随时间变化与氨态氮、氨基糖态氮和氨基酸态氮含量变化趋势相反;施氮肥处理(N120)和无作物对照(CK1)土壤非酸解态氮在甜菜生长后期（7—9 月）均出现深层残留。有机氮各组分含量（除氨基糖态氮和氨基酸态氮外）随甜菜生育进程遵循三次曲线方程的分布规律;甜菜生长过程中,土壤酸解有机氮组分中的氨态氮和氨基酸态氮为无机氮主要贡献者。  相似文献   

10.
徐州99号亩产600kg的栽培策略是：亩成穗数40～45万，每穗粒数32～35粒，千粒重42～45g。其配套栽培技术是：选择耕层深厚，基础肥力较好，土壤有机质1．2％以上，全氮0．09％以上，水解氮70ppm，速磷25ppm，速钾90ppm的田块，施足基肥。亩施有机肥500kg，纯氮9kg，P2O5，11．5kg（按P20；折算为25kg磷酸二铵），K207．5kg，硫酸锌1kg。氮肥总量每亩19．8kg纯氮，亩底施基肥11．6kg纯氮（尿素25kg）；平衡肥冬前亩追施2．3kg纯氮（尿素5kg）；穗肥亩施6kg纯氮，分两次施用，一次是在倒3叶期亩施3kg纯氮，另一次是在倒2叶未至剑叶露尖期亩施3kg纯氮。  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.
[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.
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.
[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.
Sorghum shoot fly, Atherigona soccata, is one of the important pests of postrainy season sorghums. Of the 90 sorghum genotypes evaluated for resistance to this pest, RHRB 12, ICSV 713, 25026, 93046 and 25027, IS 33844‐5, Giddi Maldandi and RVRT 3 exhibited resistance in postrainy season, while ICSB 463, Phule Anuradha, RHRB 19, Parbhani Moti, ICSV 705, PS 35805, IS 5480, 5622, 17726, 18368 and 34722, RVRT 1, ICSR 93031 and Dagidi Solapur showed resistance in rainy season, suggesting season‐specific expression of resistance to A. soccata. ICSB 461, ICSB 463, Phule Yasodha, M 35‐1, ICSV 700, 711, 25010, 25019 and 93089, IS 18662, Phule Vasudha, IS 18551 and 33844‐5 and Barsizoot had fewer deadhearts than plants with eggs across seasons, suggesting antibiosis as one of the resistance mechanism. Five genotypes exhibited resistance with high grain yield across seasons. Correlation, path and stepwise regression analyses indicated that leaf glossiness, seedling vigour, trichome density, oviposition and leaf sheath pigmentation were associated with the expression of resistance/susceptibility to shoot fly, and these can be used as marker traits to select and develop shoot fly‐resistant sorghums.  相似文献   

18.
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   

19.
[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   

20.
T. Visser  E. H. Oost 《Euphytica》1981,30(1):65-70
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   

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