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1.
番茄抗性砧木对温室根结线虫和土壤自由生活线虫群落结构动态的影响 总被引：3，自引：0，他引：3
抗性砧木嫁接是一种有效防治蔬菜根结线虫病的生物方法。研究番茄抗性砧木Beaufort(Lycopersicon ly-copersicum×L.hirsutum)对其靶标生物——根结线虫和非靶标生物——土壤自由生活线虫的种群动态和群落结构影响的结果表明:抗性砧木小区根结线虫2龄幼虫密度显著低于对照小区,根结线虫2龄幼虫取样时间之间变动显著;根据营养来源可将线虫分为4大营养类群,即食细菌、食真菌、食植物、杂食/捕食性,食真菌、食植物线虫密度变动显著,抗性砧木小区食细菌线虫密度高于对照小区,食真菌线虫密度低于对照小区;应用食真菌线虫数量/食细菌线虫数量指数F/B、修改后的F/B指数、多样性指数H′、丰富度指数D、均匀度指数J、优势度指数λ分析比较抗性砧木小区和对照区土壤线虫生物多样性变化规律,F/B、修改后的F/B、丰富度指数H′和均匀度指数J取样时间之间变动显著,F/B、修改后的F/B、优势度指数λ和均匀度J指数能较好地反映抗性砧木嫁接对线虫群落结构的影响。 相似文献
2.
黄瓜砧木对南方根结线虫生长发育的影响及其与根系分泌物的关系 总被引：1，自引：0，他引：1
黄瓜是设施主栽蔬菜,长期连作导致根结线虫病发生和危害加重;嫁接是提高黄瓜对根结线虫抗性的有效手段,但不同砧木品种间存在差异。为探明嫁接提高黄瓜抗根结线虫能力的机制,试验选用不同抗性的砧木品种‘云南黑籽南瓜’(低感)和‘甜砧南瓜’(高感),以‘新泰密刺’自根黄瓜为对照,采用人工接种,研究了黄瓜砧木对南方根结线虫生长和繁殖的影响,并探讨了根系分泌物与线虫卵孵化的关系。结果表明:线虫侵染初期,3个品种根内的二龄幼虫(J2)数差异显著,‘云南黑籽南瓜’最少,‘甜砧南瓜’次之,‘新泰密刺’最多;侵入根内的J2均能正常发育为成虫,根内线虫总数以‘云南黑籽南瓜’最少,‘新泰密刺’最多;根际J2数量以‘新泰密刺’最多,‘云南黑籽南瓜’最少;发生二次侵染前,根际卵粒数呈现出相同的特点。黄瓜及其砧木根系分泌物明显影响根结线虫卵的孵化,孵化率以‘云南黑籽南瓜’最低,‘甜砧南瓜’次之,‘新泰密刺’最高;接种根结线虫后,根系分泌物影响下的卵孵化率较未接种时明显增加,‘新泰密刺’增幅最大,‘云南黑籽南瓜’增幅最小;随着生育时间延长,三者根系分泌物对卵孵化的促进作用逐渐增强。低感砧木根系分泌物对南方根结线虫卵孵化具有明显的抑制作用,可显著降低线虫在其根内及根际的发育,可能是抗线虫的机制之一。 相似文献
3.
为探索沼液抑制根结线虫的效果,本研究通过盆栽试验,以番茄为试供作物,对比了种植前沼液淹没土壤(BSS)、种植期间浇灌沼液(BS)和加热(HE)3种方法对根结线虫的防控效果。结果表明,与不采取任何措施的对照(CK)处理相比, BSS处理抑制根结线虫效果最为明显,防效高达97.1%,根结指数分别比HE和BS处理降低96.9%和92.9%。HE处理尽管在处理土壤后显著降低了根结线虫数量,但在最后破坏性取样时(结束试验)出现反弹,根结线虫数量甚至高于CK处理。对于土壤线虫群落,CK处理中以植食性线虫为主(81.8%);两个沼液处理中食细菌线虫占优势(平均78.3%),且其中的杂食捕食性线虫在土壤前处理后消失,在试验结束时又重新出现,但所占比例依然非常低。沼液淹水方式的高效防控效果揭示了利用沼液防控根结线虫的关键期在于线虫入侵到植物根部之前的幼虫期。然而,在盆栽系统中,沼液淹水的方式也对作物生长表现出了一定的抑制趋势。高量沼液施用防控病害的同时引发的植物毒害作用以及环境污染风险,需要进一步开展田间研究。 相似文献
4.
用捕食性单齿线虫可以明显抑制由南方根结线虫引起的番茄根结症状。如果向土壤添加印度楝和蓖麻叶，则对根结症状的发展有更好的控制效果。 相似文献
5.
连作番茄根区病土对番茄生长及土壤线虫与微生物的影响 总被引：4，自引：0，他引：4
探索连作番茄根区病土对番茄根结线虫病的诱导效果及引起连作障碍的微生态机制,可为深入了解番茄连作障碍发生机理及探究番茄连作障碍防治方法提供科学依据。本研究利用盆栽试验,测定了番茄在健康土壤及接种病土土壤中生物学特性变化及根结线虫侵染状况,并分析鉴定了土壤中微生物及线虫的种类与数量。结果表明,接种连作番茄根结线虫病株根区病土会对番茄生长及根结线虫侵染产生影响:1)番茄苗期根系根结数达9个?株~(-1),健康土壤无根结;土壤线虫数量较健康土壤增加390.4%;收获期番茄根结线虫侵染率达62.7%,病情指数为80.0%。2)番茄生长受到抑制,叶片防御酶活性降低,收获期茎叶及根系鲜质量较健康土壤分别减少50.2%及33.1%,苗期番茄叶片PPO活性较健康土壤降低15.8%,POD活性较健康土壤增加24.0%,差异均达显著水平(P0.05)。3)番茄根系更易感染有害菌,根系内病原菌甘蓝假单胞菌数量较健康土壤增加463倍,根区土壤细菌、真菌及放线菌总数分别增加46.3%、94.5%及134.0%。4)食细菌线虫、食真菌线虫及植物寄生性线虫数量分别为健康根区土壤的3.3倍、1.6倍及7.3倍,其中的植物寄生线虫95.6%为根结线虫。综上所述,接入连作番茄根结线虫病株根区病土不仅导致番茄遭受根结线虫侵染,而且会导致土壤线虫总量及植物寄生线虫所占比例大幅增加,并使番茄根系内有害细菌数量显著增加,对番茄生长造成显著抑制作用,同时影响番茄的生理生化特性,受线虫侵染番茄防御性酶活性降低,使其更易被根结线虫及病原菌侵染,番茄根区土壤线虫、微生物及根系内优势细菌的种类与数量及其之间的作用发生改变。 相似文献
6.
从广西不同地区采集的28种植物根结线虫病的病原,按病原线虫的主要形态学特征和寄主反应的鉴定方法,对每种病原进行了分类鉴定。其中穗状鸡冠花、胡椒、蕹菜、胡萝卜,芭蕉芋、鸡蛋果、莞荽(香菜)、苋苯、荷包豆、吉庆果、黄麻、黄穗鸡冠等根结线虫病的病原都是属南方根结线虫1号小种;风仙花、辣椒、蕹菜、番茄、独头鸡冠花、红穗鸡冠、罗汉果、黄麻、芹菜根结线虫有一种是南方根结线虫1号小种,另一种是爪哇根结线虫;甜叶菊、姜根结线虫病的病原有一种是南方根结线虫1号小种,另一种是花生根结线虫1号小种;吉庆果、四季海棠、茄、棕竹、柳树的根结线虫病的病原是爪哇根结线虫;罗汉果、丝瓜、红麻根结线虫病的病原有一种是爪哇根结线虫,另一种是花生根结线虫1号小种;花生根结线虫病的病原是花生根结线虫1号小种。发现二个新种:即水稻根结线虫病的病原是林氏根结线虫;柑桔根结线虫病的病原是孔氏根结线虫。 相似文献
7.
温度和初始接种量对南方根结线虫侵染力的影响 总被引：1，自引：0，他引：1
在棚室盆栽条件下,研究了南方根结线虫在不同温度、不同蔬菜寄主及不同初始接种密度下的症状表现。结果表明,5—9月,气温在22.17~27.61℃之间,南方根结线虫在黄瓜上最短3 d出现明显症状;1—4月和10—12月,气温在15.38~18.67℃之间,15 d出现明显症状,显症时间延迟,发病程度受到抑制。15种感病蔬菜寄主中,以西瓜、甜瓜、苦瓜、黄瓜、南瓜、西葫芦和小青菜症状表现时间比较短,10 d以内表现症状;番茄、豇豆、茄子和甘蓝症状表现时间比较长,15 d出现症状;而韭菜和葱30 d仍未出现明显症状。南方根结线虫对6种蔬菜(黄瓜、番茄、茄子、小青菜、辣椒、韭菜)的侵染能力存在显著差异,黄瓜和番茄的根结百分率、根际二龄幼虫数、雌成虫数和卵块数显著高于茄子、小青菜、辣椒和韭菜。随着二龄幼虫接种密度的增加,番茄感病症状表现时间缩短,相应的病情指数也在增加,在接种量为80头·100g-1(土)时,4 d出现明显症状。接种量为160头·100g-1(土)时超过其饱和数量,发病率和病情指数增加不明显。 相似文献
8.
不同有机物料对连作大豆根际土壤线虫的影响 总被引：1，自引：0，他引：1
为探讨大豆连作体系下农业废弃物为主的不同有机物料对根际土壤线虫的影响,选用6种不同有机物料,设正茬和连作两种处理进行对比分析根际土壤线虫群落差异。结果表明:土壤线虫中重要的优势属和关键属种cp值均为3,说明其繁殖和抗干扰能力比较强。连作7年后根际土壤线虫营养类群中杂食-捕食性线虫相对丰度下降明显,植物寄生线虫相对丰度显著提高,食细菌线虫、食真菌线虫丰度略有提高;相较单施化肥(CK)处理,添加有机物料明显抑制连作大豆根际土壤中植物寄生线虫的大量增长,不同施肥处理效果分别为:猪粪秸秆菌渣牧草鸡粪黄腐酸生物有机肥CK,与正茬相比,各连作处理依次增长6.48%、15.34%、15.98%、18.51%、24.35%、26.33%和27.4%。土壤线虫的生态指数较CK相比也有明显改善。土壤线虫对肥料的响应取决于作物及肥料的质量和养分含量;土壤线虫优势营养类群、优势属种和关键属种可以有效地指示农业土壤健康状况和大豆田间线虫病害的发生程度。 相似文献
9.
土壤线虫和微生物群落结构与作物健康密切相关。采用田间试验，利用传统分类和高通量测序技术，研究了水稻–番茄轮作(FS)、番茄连作(FF)和休耕(CK)3种种植制度土壤线虫及微生物群落结构差异。结果表明，水旱轮作土壤中线虫种类少，自由生活线虫占比高。土壤中植物寄生线虫属的检出率，轮作最少，仅有5个，连作最多，共13个，且大部分为常见属；水旱轮作同时能降低土壤中植物寄生线虫的种类，包括主要危害番茄的根结线虫属，占比仅2.1%，而连作为29.7%。不同种植制度下真菌和细菌类群OUTs和群落结构差异明显；与连作相比，轮作和休耕真菌、细菌种群丰富度更高，共享占比更多，群落构成更相近；水旱轮作Alpha多样性指数显著高于连作；轮作土壤中植物寄生线虫拮抗微生物类群Chaetomium,Talaromyces,Anaerolineaceae和Acidobacteria相对丰度高于连作。水稻–番茄轮作能大幅减少植物寄生线虫种类，增加微生物群落多样性，改善土壤质量，是番茄生产中防控线虫病害的理想措施。 相似文献
10.
生物有机肥对甜瓜根结线虫病的田间防治效果研究 总被引：11，自引：2，他引：9
为研究生物有机肥对根结线虫的田间防治效果,在根结线虫发病严重的甜瓜田进行了田间试验。结果表明: 1）在仅施用无机肥的田块,根结线虫病发生严重,而在施用生物有机肥的田块,发病率降低,最高防治率达81.1%; 2）与对照相比,施用加入根结线虫拮抗菌X5的生物有机肥料使地上部鲜重增加,根系鲜重（根结量）减少; 3）施用生物有机肥可显著减少土壤中根结线虫二龄幼虫的密度和根中卵块的数量; 4）生物有机肥处理与常规肥料处理的土壤线虫DGGE图谱明显不同,分别归于两个聚簇,表明土壤线虫群落结构受到施用含根结线虫拮抗菌的生物有机肥影响。综上所述,施用生物有机肥能有效防治田间条件下根结线虫对甜瓜的危害。 相似文献
11.
Soil nematode biodiversity 总被引：4，自引：0，他引：4
Ernest C. Bernard 《Biology and Fertility of Soils》1992,14(2):99-103
Summary Nematodes are the most abundant metazoans in soil, and are exceeded in species diversity only by the arthropods. Estimates of nematode diversity in natural and agroecosystems have been based on both species-level taxonomy and trophic-level guilds. Because trophic groups do not act in a unitary manner with respect to environmental alterations, species-level analysis is more meaningful and should be preferred for most kinds of investigations. Nematodes of a biotope have often been considered as mere assemblages, but there is increasing evidence that certain plant associations have characteristic groups of species. This concept has been used by Bongers to develop a maturity index relating nematode families and site stability, and to identify assemblages that colonize disturbed soils. Major constraints on detailed ecological studies of soil nematode faunas are an incomplete understanding of trophic groups and their subsets, the need for repeated sampling of seasonally variable populations, and a severe shortage of taxonomy-competent persons, especially for microbial feeders. 相似文献
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《Communications in Soil Science and Plant Analysis》2012,43(15-16):1615-1634
Abstract Greenhouse and laboratory research studied K and CI nutrition of four soybean [Glycine max (L) Merril] cultivars with differential resistance to Soybean Cyst Nematode (SCN, Heterodora glycines Ichinohe). The cultivars: Forrest (Group V, resistant to races 1 and 3), Bradley (Group VI, resistant to races 1, 3 and 4), Essex (Group V, susceptible), and Davis (Group VI, susceptible*) were used. Potassium treatments were zero K, K2SO4 and KCI, and SCN treatment was zero and 500 eggs/100 g of previously sterilized soil. Single plants were grown for 30‐days in 400 g of soil in 3.5 cm pots maintained at 23°C. Plants were separated into roots and shoots for analysis. Post harvest SCN cyst counts were completed to evaluate cultivar‐K treatment effect on SCN population dynamics and treatment effects on root and shoot K, Ca, Mg and CI. Cyst counts were a function of cultivar resistance and inoculation, and were not affected by K treatment. Root and shoot weights of all cultivars were lower In the SCN inoculated pots. Potassium treatments did not alter the SCN negative effect on root weight, but KCI appeared to reverse the negative effect that SCN inoculation had on shoot weight of Bradley. SCN Inoculation appeared to reduce CI concentration in the roots of all cultivars, increase root K of Bradley and no effect on root K of Davis, Essex and Forrest. Transiocation of K from roots to shoots was not adversely affected by SCN inoculation. The KCI treatment increased shoot CI concentration of cultivars in order Essex > Davis > Forrest > Bradley. The order of correlation of root CI concentration with shoot CI concentration was: Essex (r = 0.80**) > Bradley (r = 0.70**) > Davis (r = 0.54**) > Forrest (r = 0.40**) suggesting difference in root CI adsorption characteristcs and CI translocation characteristis to the shoots. Additional research is needed to determine to what extent root and shoot CI accumulation characteristics are related to SCN resistance and if the shoot CI accumulation characteristics is independent of root CI adsorption characteristics. 相似文献
14.
《Applied soil ecology》2007,35(1):68-78
The effect of land use changes on the composition of nematode communities has been well documented, however, the applicability of such studies limited to areas with relatively uniform soil and environmental conditions. To determine whether the historical difference in vegetation types affects soil nematode communities during the land use change processes, we carried out a study along two transects where contrasting natural vegetation types (grass versus shrub) were replaced by tea monocultures. Soil nematode communities were compared between two transects at three chronosequence stages: natural vegetations, 3–7 years old tea plantations. Nematode abundance, generic richness, diversity, and proportions of bacterivores and fungivores were higher at each stage of GT transect (from grassland to tea plantation) than at the equivalent stage of ST transect (from shrubland to tea plantation), whereas lower values of maturity index and nematode channel ratio occurred at each stage of GT transect relative to ST transect. MDS ordination analyses, SIMPER analyses and βw indices indicated that the difference in nematode community structure was greatest between the two 3-year-old tea plantations, although the greatest difference in environmental conditions was observed between two original vegetation habitats. This suggested that the original vegetation types may affect the following nematode community development; however, the effects can decrease over time. Different trophic groups responded to land use in different ways along the vegetational development. This supports the viewpoint that the addition of a common resource can evoke disparate responses from individual food-web components. 相似文献
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16.
铜污染土壤线虫多样性的PCR-DGGE分析 总被引：11，自引：1，他引：10
A wheat pot experiment was conducted under greenhouse conditions to assess the effect of copper contamination on soil nematode diversity by polymerase chain reaction-denaturing gradient gel electrophoresis （PCR-DGGE） method and morphological analysis. The soil was treated with CuSO4.5H2O at the following concentrations： 0, 50, 100, 200, 400, and 800 mg kg^-1 dry soil, and the soil samples were collected at wheat jointing and ripening stages. Nematode diversity index （H′） from morphological analysis showed no difference between the control and the treated samples in either of the sampling dates. At the wheat ripening stage, nematode diversity obtained by the PCR-DGGE method decreased noticeably in the Cu800 treatment in comparison with the control. With optimization of the method of nematode DNA extraction, PCR-DGGE could give more information on nematode genera, and the intensity of the bands could reflect the abundance of nematode genera in the assemblage. The PCR-DGGE method proved promising in distinguishing nematode diversity in heavy metal coritaminated soil. 相似文献
17.
《European Journal of Soil Biology》2002,38(3-4):255-259
There is increasing evidence supporting rapid trajectories of environmental change in the Antarctic. This study describes preliminary data on soil faunal responses to artificial environmental amelioration obtained using a ‘greenhouse’ methodology, over the first year of a manipulative study of part of the soil ecosystem of Mars Oasis, Alexander Island in the southern Maritime Antarctic. The methodology, which used two types of UV-absorbing perspex cloche, influences a range of environmental variables, the most significant of which in this study are thought to be temperature and UV-radiation. The fauna of this site is dominated by Nematoda. Responses to amelioration included large increases in nematode population densities, particularly those of the microbivorous genus, Plectus, combined with changes in the relative abundance of taxa. These faunal changes are likely to be mediated via the responses of autotrophs to the environmental manipulations. 相似文献
18.
The chronic impact of ring nematode (Mesocriconema xenoplax) feeding on grapevine (Vitis vinifera) was studied under controlled conditions. ‘Pinot noir’ grapevines were exposed to ring nematode or kept nematode-free for three growing seasons and vines were either grown in full sunlight, 15% of full sun, or partially defoliated to manipulate vine carbohydrate status. Whole plants were destructively sampled to assess the impact of ring nematode on whole plant biomass, carbohydrate, and mineral nutrient accumulation. Vine shoot growth and total biomass was unaffected by ring nematode in the first growing season, although reserves of nonstructural carbohydrates (NSC), P, K, and Ca in the roots and wood were reduced in all canopy management treatments. Vine shoot growth and total biomass were reduced by ring nematode in Year 2, and greater declines in reserve NSC and most mineral nutrients had occurred. Reserves of NSC were affected more than biomass or nutrients during the second year. During the third year of exposure to ring nematode, vines in the 15% sun treatment were dying (prompting an earlier destructive harvest), even though these vines had similar biomass and NSC reserves as the partially defoliated vines at the end of the second year. The demise of the 15% sun vines was associated with higher ring nematodes per unit of root mass, as compared to either full sun or defoliated vines. Therefore, predicting plant response to this nematode requires an understanding of nematode density per quantity of roots, not nematodes per unit of soil which is how plant parasitic nematodes are currently enumerated. 相似文献
19.
土壤食细菌线虫对菲降解的影响 总被引：1，自引：0，他引：1
以菲作为多环芳烃污染物的代表,通过室内培养试验研究了在菲降解菌恶臭假单胞菌存在与否的条件下,接种食细菌线虫对未灭菌土壤中菲去除的影响。析因设计包括4个处理:单独接种恶臭假单胞菌(B),单独接种食细菌线虫(N),同时接种食细菌线虫和恶臭假单胞菌(BN)以及未接种线虫和细菌的对照(CK);分别在培养后第0、5、14、28天进行破坏性采样,测定土壤中菲的残留量,食细菌线虫和恶臭假单胞菌的数量,土壤FDA(荧光素二乙酸酯)水解酶、过氧化氢酶的活性。结果显示,相比CK,在培养前期(0~14天),处理N提高土壤中菲的去除率;而在培养后期(14~28天),BN处理降解菲的优势逐渐显现出来。在培养结束(28天)时,各处理菲的去除率依次为BN(48.2%)B(45.1%)N(44.4%)CK(43.5%)。试验结果还表明,接种食细菌线虫能显著(p0.05)促进细菌以及土壤酶活性。总之,食细菌线虫和细菌的交互作用可能促进土壤中菲的降解。 相似文献