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外来入侵植物猫爪藤概述 总被引：6，自引：0，他引：6
外来植物猫爪藤，早年曾作为观赏植物引入我国，目前已经被列为中国的外来入侵种。本文概述了国内外对猫爪藤的研究状况，简要介绍了猫爪藤的分类学特征和群落分布，论述了其生态特征和危害，指出了防治的困难及其可利用性。在南非，人工防治和化学防治的效果不大，因而引入吃叶片的龟甲科昆虫Charidotis auroguttata作为生物防治试剂。在澳大利亚，化学防治取得了一定的效果，但人们还是把目光转向生物防治。尽管人们对防治策略开展了不少研究，但是到现在为止，国外还没有任何一种清除猫爪藤的有效方法。猫爪藤在许多国家被作为民间药物。因此，应该全面深入地认识猫爪藤，采取防治和利用相结合的综合措施。 相似文献
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何首乌主要病虫害的发生规律与防治 总被引：1，自引：0，他引：1
何首乌为蓼科蓼属植物Polygonum multiflorum Thunb.的块根,若以茎藤入药则称为首乌藤或夜交藤。何首乌在贵州大多数县(市)均有野生分布,是贵州地道药材之一。近年来,在黔东南州的施秉、黄平、凯里、从江、剑河等县市何首乌人工种植面积得到迅速发展。据调查,贵州何首乌主要病虫害 相似文献
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胡治强侯振安闵伟冶军吴颜 《干旱区研究》2018,(4):779-788
过量灌溉导致土壤水分深层渗漏是滴灌农田水分无效损失的重要途径,地下防渗可有效减少土壤水分深层渗漏,提高农田水分利用效率。2015—2016年通过田间试验研究不同灌水量下地下防渗对滴灌棉田水分平衡、棉花产量及水分利用率的影响。采用灌水量和地下防渗2因素3水平（3×3）试验设计,其中,3个灌水量水平为340、440 mm和540 mm;3个地下防渗处理分别为：对照（无防渗）、地下防渗埋深40 cm和60 cm。结果表明：地下防渗处理（埋深40,60 cm）0-60 cm土壤含水量和净贮水量显著高于对照。随灌水量增加,土壤水分深层渗漏损失量显著增加。灌水量340 mm条件下,地下防渗对水分渗漏量影响不显著。灌水量440 mm和540 mm条件下,地下防渗埋深40 cm、60 cm处理水分渗漏损失量较对照分别减少64%、72%和38%、76%。低灌水量下（340 mm）,地下防渗处理（埋深40,60 cm）棉田蒸散量显著低于对照;而高灌水量下（540 mm）,地下防渗埋深60 cm处理棉田蒸散量显著高于对照。中、低灌水量下（440,340 mm）,地下防渗处理棉花干物质重、产量、水分利用率和经济效益均显著高于对照;但地下防渗埋深40 cm和60 cm处理间差异不显著。高灌水量下（540 mm）,地下防渗埋深60 cm显著提高棉花干物质重、产量、水分利用率和经济效益,地下防渗埋深40 cm处理与对照无显著差异。因此,中、低灌水量（440,340 mm）地下防渗埋深40 cm或60 cm均较适宜,而高灌水量（540 mm）采用地下防渗埋深60 cm较为适合。 相似文献
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地下防渗对滴灌棉花产量和水分利用率的影响 总被引：2，自引：1，他引：1
过量灌溉导致土壤水分深层渗漏是滴灌农田水分无效损失的重要途径,地下防渗可有效减少土壤水分深层渗漏,提高农田水分利用效率。2015—2016年通过田间试验研究不同灌水量下地下防渗对滴灌棉田水分平衡、棉花产量及水分利用率的影响。采用灌水量和地下防渗2因素3水平(3×3)试验设计,其中,3个灌水量水平为340、440 mm和540 mm;3个地下防渗处理分别为:对照(无防渗)、地下防渗埋深40 cm和60 cm。结果表明:地下防渗处理(埋深40,60 cm)0~60 cm土壤含水量和净贮水量显著高于对照。随灌水量增加,土壤水分深层渗漏损失量显著增加。灌水量340 mm条件下,地下防渗对水分渗漏量影响不显著。灌水量440 mm和540 mm条件下,地下防渗埋深40 cm、60 cm处理水分渗漏损失量较对照分别减少64%、72%和38%、76%。低灌水量下(340 mm),地下防渗处理(埋深40,60 cm)棉田蒸散量显著低于对照;而高灌水量下(540 mm),地下防渗埋深60 cm处理棉田蒸散量显著高于对照。中、低灌水量下(440,340 mm),地下防渗处理棉花干物质重、产量、水分利用率和经济效益均显著高于对照;但地下防渗埋深40 cm和60 cm处理间差异不显著。高灌水量下(540 mm),地下防渗埋深60 cm显著提高棉花干物质重、产量、水分利用率和经济效益,地下防渗埋深40 cm处理与对照无显著差异。因此,中、低灌水量(440,340 mm)地下防渗埋深40 cm或60 cm均较适宜,而高灌水量(540 mm)采用地下防渗埋深60 cm较为适合。 相似文献
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围栏封育对新疆蒿类荒漠草地植被及土壤养分的影响 总被引：10，自引：0，他引：10
以新疆封育3年的蒿类荒漠草地为对象,研究干旱区封育对草地植被及土壤养分的影响.结果表明:封育后荒漠草地群落的盖度、产量明显增加(P<0.05),分别比对照提高了11.0%,51.6 g/m~2,且盖度、产量的增加主要是由藜科草类引起;荒漠草地80%以上的地下生物量集中在0～40 cm土层中,且封育促进了0～10 cm土层内生物量的增加(P<0.05);与放牧地相比,封育后土壤有机质、全氮、全磷、全钾及速效氮、磷、钾含量均有所提高,且在0～10 cm的土层中差异显著(P<0.01),而pH值略有上升. 相似文献
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固沙植被土壤水分动态及其对降雨的响应 总被引：3，自引：0，他引：3
水分是影响固沙植被生长发育的最重要的限制因素,同时也是沙漠环境中最容易受到影响的生态因子。因此,定位观测研究流动沙地建立固沙植被后土壤水分变化具有重要的现实意义。文中采用Watchdog土壤水分自动监测系统,定位定时记录了7月1日-10月31日期间杨柴固沙林、固定沙丘天然草地和流动沙丘土壤体积含水量数值。结果表明:相同降水量条件下,不同固沙植被土壤重力水湿润深度存在明显差异。5.33mm降雨时流动沙丘水分湿润深度小于20cm,13.97mm降雨时水分湿润深度达40cm,30.3mm降雨时水分湿润深度达80cm,40.3mm降雨时水分湿润深度达120cm。而30.3mm及以下降雨时杨柴固沙林和天然草地植被土壤水的湿润深度小于40cm;40.3mm降雨时杨柴固沙林地水分湿润深度达80cm,天然草地植被水分湿润深度达120cm。植物生长季流动沙地土壤水分状况最好。流动沙丘20cm、40cm、80cm和120cm土层含水量平均值分别为2.15%、2.42%、1.96%和2.94%;而杨柴固沙林和天然草地植被下土壤水分状况明显不良,特别是80cm土层以下土壤水分状况明显恶化。杨柴固沙林生长期20cm、40cm、80cm和120cm土层含水量平均值分别为1.89%、1.67%、0.81%和1.08%;天然草地植被生长期20cm、40cm、80cm和120cm土层含水量平均值分别为2.34%、1.96%、1.02%和1.43%。 相似文献
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含水率控制问题,始终是出口藤制工艺品检验检疫工作中最敏感的问题之一。对其控制过严,则会阻碍出口,过松又会因霉变而遭受索赔。本试验按20%、18%、16%、14%、12%、10%的含水率标准,将藤放入烤房烘烤,达到上述标准后,取出来,再将各不同含水率的藤分为原色藤、敷金粉藤、敷银粉藤3类放在自然条件下不设通风口的A、B、C 3个库中,持续观察180 d,检查其霉变情况。结果显示,12%和10%含水率的原色藤180 d后仍不长霉,14%、12%、10%3种含水率的敷金粉藤和敷银粉藤180 d后均不长霉。由此认为,检验检疫人员对藤制工艺品进行检验检疫监管时,对原色藤工艺品,其含水率应控制在8%～12%,对敷金、银(包括其他颜色)粉藤工艺品,其含水率应控制在10%～14%。 相似文献
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耕作模式和播种方式对旱地小麦产量形成的影响 总被引：1，自引：0，他引：1
于2015—2017年在山西省闻喜旱地小麦试验示范基地开展大田试验,以耕作模式为主区,设休闲期深翻和免耕两种模式,以播种方式为副区,设探墒沟播、膜际条播和常规条播3种方式,研究旱地小麦土壤水分、产量形成和经济效益的差异。结果表明：休闲期深翻显著提高旱地小麦播前0～300 cm土壤蓄水效益,达46.97%～240.44%;提高旱地小麦生育时期土壤耗水量,达6.48%～13.07%;提高穗数、穗粒数、千粒重和产量,分别达3.32%～7.22%、3.67%～6.53%、1.11%～3.61%、10.23%～13.16%。探墒沟播和膜际条播较常规条播显著提高了旱地小麦茎蘖成穗率,达5.99%～16.87%,显著提高穗长0.8～1.7 cm,提高可孕小穗数1～3个;提高了穗数、穗粒数,分别达5.28%～15.75%和1.51%～11.25%,此外,休闲期深翻后采用探墒沟播较膜际条播减少投入1 200元·hm-2,主要是旋耕机械投入、地膜和回收地膜人工投入,增加经济效益622～754元·hm-2。休闲期深翻后采用探墒沟播较常规条播减少投入300元·hm<... 相似文献
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覆盖处理苹果细根分布与土壤物理性状响应关系研究 总被引：5，自引：0，他引：5
以12年生红富士苹果树为试材,研究黄土高原旱塬区不同覆盖措施(覆膜、覆草、覆沙)对苹果细根(直径≤2 mm)及土壤性状的影响。结果表明:地表覆盖可有效降低土壤容重,增大土壤含水量及孔隙度,增加细根数量,增大根系吸收水肥效率。覆膜处理细根水平分布范围与清耕(CK)相似,在距干0~90 cm范围内,垂直密集分布最大深度由CK的60 cm提升至40 cm,36.05%的细根分布在0~20 cm土壤表层。与CK相比,覆草、覆沙处理的细根水平分布范围由90 cm扩展至120 cm,垂直均匀分布整个土壤剖面,利于树体对深层土壤水肥的吸收利用。土壤物理性状与细根根长、表面积、根长密度呈极显著相关,覆膜处理中根径与比根长也与土壤物理性状表现出相关性。综合分析根系分布与土壤物理性状,覆草处理是陇东旱塬区苹果园较为适宜的地表覆盖模式。 相似文献
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Belle Cristiano Kaspary Tiago Edu Groth Mártin Zanchett Cocco Kassia Luiza Teixeira 《植物病害和植物保护杂志》2017,124(4):393-397
Journal of Plant Diseases and Protection - Samples of melon plants with aerial symptoms that represented yellowing of leaves and stunting, and below-ground galls on the roots from two growing areas... 相似文献
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采用根管土柱栽培的方法,研究了拔节期和抽穗期切断不同深度(20 cm和40 cm)根系对黍子根系整体及地上部营养生长的影响。结果表明,与不断根相比,在抽穗期和拔节期断掉20 cm或40 cm以下根系,均能导致黍子株高、旗叶叶绿素含量、旗叶SOD与POD活性、单株绿叶面积、总根活力、总根长、总根重及产量明显降低,旗叶M DA含量明显增高。抽穗期断深层根对黍子的影响大于拔节期。但同一生育时期不同深度断根处理间黍子产量差异未达显著水平,表明深层根系(40 cm以下根系)对产量的贡献更大。 相似文献
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Alpine meadow ecosystem is fragile and highly sensitive to climate change.An understanding of the allocation of above-and below-ground plant biomass and correlations with environmental factors in alpine meadow ecosystem can result in better protection and effective utilization of alpine meadow vegetation.We chose an alpine meadow in the Qinghai-Tibetan Plateau of China as the study area and designed experimental warming plots using a randomized block experimental design.We used single-tube infrared radiators as warming devices,established the warming treatments,and measured plant above- (AGB) and below-ground biomass (BGB) during the growing seasons (May to September) in 2012 and 2013.We determined the allocation of biomass and the relationship between biomass and soil environment under the warming treatment.Biomass indices including above-ground biomass,below-ground biomass and the ratio of root to shoot (R/S) ,and soil factors including soil moisture and soil temperature at different depths were measured.The results showed that (1) BGB of the alpine meadow had the most significant allometric correlation with its AGB (y=298.7x~ (0.44) ,P0.001) ,but the relationship decreased under warming treatment and the determination coefficient of the functional equation was 0.102 which was less than that of 0.188 of the unwarming treatment (control) ; (2) BGB increased,especially in the deeper soil layers under warming treatment (P0.05) .At 0–10 cm soil depth,the percentages of BGB under warming treatment were smaller than those of the control treatment with the decreases being 8.52% and 8.23% in 2012 and 2013,respectively.However,the BGB increased 2.13% and 2.06% in 2012 and 2013,respectively,at 10–50 cm soil depths; (3) BGB had significant positive correlations with soil moisture at 100 cm depth and with soil temperature at 20–100 cm depths (P0.05) ,but the mean correlation coefficient of soil temperature was 0.354,greater than the 0.245 of soil moisture.R/S ratio had a significant negative correlation with soil temperature at 20 cm depth (P0.05) .The warmer soil temperatures in shallow layers increased the biomass allocation to above-ground plant parts,which leading to the increase in AGB;whereas the enhanced thawing of frozen soil in deep layers causing by warming treatment produced more moisture that affected plant biomass allocation. 相似文献
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干旱区绿洲核桃-冬小麦间作系统核桃吸收根空间分布 总被引：1，自引：0，他引：1
塔里木盆地人均耕地占有量小,在绿洲灌溉条件下核桃的大面积栽植多采用与农作物间作的模式。采用田间分层挖掘法和图像扫描分析法,对塔里木盆地绿洲灌溉条件下核桃-冬小麦间作系统中核桃吸收根（直径≤1 mm）的空间分布进行研究。结果表明：在垂直方向上,核桃吸收根集中分布在10～80 cm土层,约占采样吸收根总根长密度的65.9%,根长密度随土层深度的变化呈指数函数分布;在水平方向上,核桃吸收根根长密度随着与树干距离的增加呈明显的降低趋势,距离两侧核桃树干0～175 cm,核桃吸收根长密度占采样吸收根总根长密度的65.3%,间作巷道中央吸收根根长密度最低。在绿洲灌溉条件下,核桃-冬小麦间作系统中核桃吸收根水平和垂直分布决定了进入盛果期后,距离树干175 cm以内的10～60 cm土层是核桃与冬小麦的主要水肥竞争区域。 相似文献
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《Physiological and Molecular Plant Pathology》2002,60(3):103-109
Expression of Tenod40, a tobacco (Nicotiana tabacum cv. Xanthi nc) homologue of Msenod40, a gene expressed early during alfalfa (Medicago sativa) nodule development, was significantly and consistently increased (about three-fold) in tobacco roots of plants grown in sand and colonized by the arbuscular mycorrhizal (AM) fungus Glomus intraradices, as compared to non-mycorrhizal controls. In alfalfa (Medicago sativa cv. Gilboa), a similar induction of Msenod40 expression was also detected in mycorrhizal vs. non-mycorrhizal roots. In the same experimental system, the application of the cytokinin 6-benzylaminopurine to non-mycorrhizal roots resulted in a similar increase in Msenod40 expression. A significantly higher incidence of AM fungal colonization (vesicles per cm of root) in M. sativa cv. Gilboa roots was observed following application of luteolin-induced Sinorhizobium meliloti exudates as compared to plants amended with non-induced exudates. Moreover, overexpression of the Mtenod40 gene in Medicago truncatula plants under the control of a 35S constitutive promoter resulted in significantly enhanced colonization as compared to non-transgenic plants. The fact that enod40 gene expression was increased both in a legume and in a non-legume during colonization by the AM fungus, and that colonization levels were higher in enod40 -overexpressing transgenic plants strongly suggests that this gene is involved in the establishment of the fungal partner in its host. 相似文献
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通过对青海省治沙试验站3 a、5 a、10 a、16 a和30 a生的中间锦鸡儿(Caragana intermedia Kuang et H. C.Fu)人工林细根生物量的测定分析,了解其细根生物量的垂直分布和动态变化特征以及周转速率。结果表明:①中间锦鸡儿人工林约41%的活细根和39%的死细根分布在0~20 cm的土层,38%的活细根和死细根分布在20~40 cm的土层,21%的活细根和23%的死细根分布在40~60 cm的土层。②细根生物量表现出明显的季节动态性,活细根生物量峰值出现在6月和8月或者6月和9月,8月或9月达到最大值;死细根生物量峰值出现8月和9月,也是8月或9月达到最大值。③不同林龄人工林细根周转速率分别为:0. 53、0. 66、0. 56、0. 73、0. 78次·a^-1。④细根生物量和周转率均随林龄增大而增加,随土层加深而减小。 相似文献
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The effect of take-all root lesions on nitrate uptake of wheat was investigated in two experiments under controlled conditions. Plants were supplied with a nutrient solution labelled with 15 N during stem elongation and flowering to assess the distribution of the isotopic tracer in the different plant organs, and particularly in root segments located on both sides of take-all lesions. The 15 N atom percentage excess measured in root segments located below lesions longer than 1 cm was reduced on average by half compared with that in healthy roots and root segments above lesions, reflecting a reduction in nitrogen uptake by these root segments. This reduction probably resulted from the invasion and breakdown of phloem vessels by the fungus hyphae, interrupting energy supply and thus the uptake process. Severely infected plants showed an increase in the uptake rate per unit of efficient root, which appeared to be a compensatory response to reduction of efficient root biomass in order to satisfy shoot nitrogen demand. However, this compensatory response was insufficient to ensure nitrogen accumulation equivalent to that of healthy plants, as reductions in nitrogen accumulated in roots and aerial parts at flowering were up to 56 and 49%, respectively, for plants with more than 50% of the root system below lesions longer than 1 cm. 相似文献
19.
The extent of colonization by Heterobasidion annosum was measured in 1989 in Sitka spruce stumps that had been inoculated with basidiospores in 1981 and assessed for infection in 1983. Only stumps that had infection in the sapwood in 1983 contained the fungus in 1989. There was a significant positive correlation between the sapwood area colonized in 1983 and the total area colonized in 1989. Between 1983 and 1989, H. annosum spread within the body of stumps and into most primary roots. There were significant correlations between the stump area colonized in 1983 and 1989 and the percentage of stump and root volume colonized in 1989. Roots of 26 excavated stumps were in contact with an average of two roots on each of two living trees. Fourteen roots on eight living trees became infected, and H. annosum spread proximally an average of 126 cm into trees. We believe that this is the first report of the transfer of H. annosum from spruce stumps inoculated with basidiospores to adjacent live trees. 相似文献
20.
通过对青海省治沙试验站3 a、5 a、10 a、16 a和30 a生的中间锦鸡儿（Caragana intermedia Kuang et H. C. Fu）人工林细根生物量的测定分析，了解其细根生物量的垂直分布和动态变化特征以及周转速率。结果表明：① 中间锦鸡儿人工林约41％的活细根和39％的死细根分布在0～20 cm 的土层，38％的活细根和死细根分布在20～40 cm 的土层，21％的活细根和23％的死细根分布在40～60 cm 的土层。② 细根生物量表现出明显的季节动态性，活细根生物量峰值出现在6月和8月或者6月和9月，8月或9月达到最大值；死细根生物量峰值出现8月和9月，也是8月或9月达到最大值。③ 不同林龄人工林细根周转速率分别为：0.53、0.66、0.56、0.73、0.78次﹒a-1。细根生物量和周转率均随林龄增大而增加，随土层加深而减小。 相似文献