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1.
This study examined the performances of 21 cassava cultivars in two cropping seasons on the field against root rot disease and the yield in cassava-maize intercrop. Data were collected on number of root/plant, weight of root (t/ha) and disease severity (DS) on rotted roots at 12 and 16 months after planting (MAP), respectively. There were significant (P ≤ 0.05) differences for DS at 12 and 16 MAP in both seasons with cultivar TMS 97/JW2 having the least DS score. TMS 97/JW2 was resistant to the root rot pathogen, while eleven other cultivars were moderately resistant to the disease at 16 MAP. There was no consistency in the roots weight for the cultivars over the two cropping seasons but higher roots weight was recorded at 16 MAP than 12 MAP with different cultivars having highest roots weight at these periods. Intercropping maize with cassava does not have any management potential on root rot development.  相似文献   

2.
The study focused on the phytoattenuation effects of monocropping and intercropping of maize (Zea mays) and/or legumes on Cu, Zn, Pb, and Cd in weakly alkaline soils. Nine growth stages of monocropping maize were chosen to study the dynamic process of extraction of heavy metals. The total content of heavy metals extracted by the aerial part of monocropped maize increased in a sigmoidal pattern over the effective accumulative temperature. The biggest biomass, highest extraction content, and lowest heavy metals bioaccumulation level occurred at physiological maturity. Among the different planting patterns, including monocropping and intercropping of maize and/or soybean (Glycine max), pea (Pisum sativum), and alfalfa (Medicago sativa), the extraction efficiency of Cu, Zn, Pb, and Cd varied greatly. Only intercropping of maize and soybean yielded relatively higher extraction efficiency for the four metals with no significant difference in the total biomass. Moreover, the heavy metals concentrations in dry biomass from all the planting patterns in the present study were within China's national legal thresholds for fodder use. Therefore, slightly polluted alkaline soils can be safely used through monocropping and intercropping of maize and/or legumes for a range of purposes. In particular, this study indicated that intercropping improves soil ecosystems polluted by heavy metals compared with monocropping.  相似文献   

3.
Multispecies cropping systems contribute to sustainable agriculture with multiple ecosystem services. Effects of intercropping of various crops with faba beans on growth and yield parameters and disease severity of root rot, damping off and broomrape were investigated. This study was implemented in the laboratory, greenhouse and field to investigate the effect of the intercropping systems (fenugreek + faba bean, lupine + faba bean, garlic + faba bean and sole faba bean). The intercropping systems were combined with the application of arbuscular mycorrhiza fungi (AMF) and yeast as bio-control agents, compared to chemical application of herbicides (Glyphosate) and fungicides (Rizolex-T50), to control rot root diseases and broomrape weeds, Orobanche spp., of faba bean plants in vivo and under the naturally infested field. In vitro, yeast and Rizolex-T50 significantly inhibited mycelial growth of root pathogenic fungi. Intercropping with garlic and/or application of Rizolex-T, significantly decreased the incidence and disease index of root rot and damping-off diseases, meanwhile increased percentage of survival plants. In vivo, intercropping with fenugreek and/or application of Glyphosate, significantly reduced the number/weight of spikes/plot of broomrapes. Intercropping with fenugreek combined with AMF application promoted crop growth and significantly increased yield components. The AMF enhanced seed yield/ha when applied to the intercropping of faba bean + fenugreek and faba bean + garlic, showing the highest seed yield/ha with 3.722 and 3.568 ton/ha, respectively. Intercropping of faba bean with garlic integrated with AMF revealed the highest values of LER, 2.45, and net return, 2341 US$/ha. Our results suggested that using faba bean–garlic intercrop along with AMF inoculation can reduce root rot disease, damping off and broomrapes, as well as enhance the profitability of Egyptian farmer and sustainable production.  相似文献   

4.
玉米/花生间作对土壤微生物和土壤养分状况的影响   总被引:19,自引:0,他引:19  
通过大田试验,研究了玉米/花生间作对玉米和花生根区土壤微生物和土壤养分状况的影响.结果表明:与单作相比,间作能显著提高玉米和花生根区的土壤细菌数量;间作花生根区土壤真菌和放线菌数量与单作无显著差异;间作玉米根区土壤真菌和放线菌数量比单作明显提高;间作作物根区微生物群落功能多样性和代谢活性比单作有所改善.玉米/花生间作不同程度提高了整个间作系统根区的土壤碱解氮、速效磷、有机质含量及EC值,其中,间作玉米根区土壤养分的增加更为明显,说明玉米/花生间作可以较明显地改善两种作物根区的微生物和养分状况,土壤微生态环境的改善又会促进作物地上部的生长.  相似文献   

5.
Diverse intercropping system has been used to control disease and improve productivity in the field. In this research, the bacterial communities in salt–alkali soils of monoculture and intercropping mulberry and soybean were studied using 454‐pyrosequencing of the 16S rDNA gene. The dominant taxonomic groups were Proteobacteria, Acidobacteria, Actinobacteria, Chloroflexi, Bacteroidetes, Planctomycetes and Gemmatimonadetes and these were present across all samples. However, the diversity and composition of bacterial communities varied between monoculture and intercropping samples. The estimated bacterial diversity (H') was higher with intercropping soybean than in monoculture soybean, whereas H' showed an opposite pattern in monoculture and intercropping mulberry. Populations of Actinobacteria, Acidobacteria, and Proteobacteria were variable, depending on growth of plants as monoculture or intercropped. Most of Actinobacteria and Chloroflexi were found in intercropping samples, while Acidobacteria and Proteobacteria were present at a higher percentage in monoculture samples. The plant diversity of aboveground and microbial diversity of belowground was linked and soil pH seemed to influence the bacterial community. Finally, the specific plant species was the major factor that determined the bacterial community in the salt–alkali soils.  相似文献   

6.
间作栽培对连作马铃薯根际土壤微生物群落的影响   总被引:6,自引:0,他引:6  
连作严重影响了作物的产量和品质,而土壤微生物群落结构与功能对土壤生态系统和植物健康至关重要。以连作10a土壤为基质,单作马铃薯为对照,采用磷脂脂肪酸(Phospholipid fatty acids)、BIOLOGA技术和真菌形态学鉴定方法,研究了玉米、蚕豆与马铃薯间作模式下土壤微生物群落结构、功能和丛植菌根(Arbuscular Mycorrhizal)真菌对土壤环境变化的响应。结果表明:间作调控下,马铃薯根际土壤微生物主要类群结构发生显著改变;玉米间作马铃薯,土壤微生物群落总生物量降低,但群落功能多样性提高,促进了以羧酸类、多聚化合物、芳香类化合物、氨基酸类化合物为碳源的微生物类群代谢活性增强;蚕豆间作增加了土壤微生物总生物量,仅促进了以碳水化合物为碳源的微生物类群代谢活性。间作改变了作物根际土壤AM真菌的种、属数,AM真菌多样性降低,优势种由明球囊霉、地球囊霉转变为玉米间作体系里的福摩萨球囊霉、球泡球囊霉;蚕豆间作体系里福摩萨球囊霉和疣状无梗囊霉是优势种。间作栽培下AM真菌优势种群的变化可能受植物间的共生关系、微生物结构与功能等因素的制约。间作条件下,玉米显著影响了马铃薯根际土壤微生物群落功能多样性,而蚕豆则显著改变了微生物群落结构多样性;玉米、蚕豆对马铃薯根际土壤微生物群落功能与结构变化的影响不同步;间作调控后持续的土壤微生物群落结构与功能观察才有助于解释土壤微生物结构变化引起的功能响应。  相似文献   

7.
This study aims to explore relationships between plant diversity and soil microbial function and the factors that mediate the relationships. Artificial plant communities (1, 2, 4 and 8 species) were established filled with natural and mine tailing soils, respectively. After 12 months, the plant species richness positively affected the soil microbial functional diversity in both soil environments but negatively affected microbial biomass and soil basal respiration in the natural soil. The root biomass positively correlated with the microbial biomass, cultural bacterial activity and soil basal respiration in both soil environments. Moreover, the Di (deviations between observed performances and expected performances from the monoculture performance of each species of mixture) of microbial biomass, cultural bacterial activity and soil basal respiration positively correlated with the Di of root biomass in both soil environments. Consistent with stress-gradient hypothesis, the Dmix (over-function index) of aboveground biomass positively correlated plant species richness in the mine tailing soil. Results suggest that the root biomass production is an important mechanism that affects the effects of plant diversity on soil microbial functions. Different responses of soil microbial function to increasing plant diversity may be due to root biomass production mediated by other factors.  相似文献   

8.
Several studies were carried out to investigate the soil microbial components involved in suppressing strawberry black rot root which occurs throughout the Italian strawberry growing region. Quantitative and qualitative evaluation of fungi involved in black root rot were combined with several soil microbial parameters involved in soil suppressiveness towards black root rot agents. The first survey, carried out in an intensively cultivated area of northern Italy, identified Rhizoctonia spp. as the main root pathogen together with several typical weak pathogens belonging to the well‐known black rot root complex of strawberry crop: Cylindrocarpondestructans, Fusarium oxysporum, F. solani, Pestalotia longiseta and others. The root colonisation frequency of strawberry plants increased strongly from autumn to spring at harvesting stage. Rhizoctonia spp. were the only pathogens which followed the rising trend of root colonisation with relative frequency; all the weak pathogens of strawberry black root rot complex did not vary their frequency. Only non‐pathogenic fungi decreased from autumn to spring when at least 60% of colonising fungi were represented by Rhizoctonia. These data suggested that the late vegetative stage was the best time to record the soil inoculum of root rot agents in strawberry using root infection frequency as a parameter of soil health. A further study was performed in two fields, chosen for their common soil texture and pH, but with significant differences in previous soil management: one (ALSIA) had been subjected to strawberry monoculture without organic input for several years; the other (CIF) has been managed according to a 4‐year crop rotation and high organic input. In this study Pythium artificially inoculated was adopted as an indicator for the behaviour of saprophytically living pathogens in bulk soil. Pythium showed a sharp, different response after inoculation in bulk soil from the two soil systems evaluated. Pythium was suppressed only in the CIF field where the highest levels of total fungi and fluorescent bacteria and highest variability were observed. The suppressiveness conditions towards Pythium, observed in the CIF and absent in the ALSIA field, corresponded with the root infection frequency recorded at the late vegetative stage on strawberry plants grown in the two fields: strawberry plants from the CIF field showed lower root colonisation frequency and higher variability than that recorded on those coming from the ALSIA field.  相似文献   

9.
为了解辽西北沙地果农间作系统中土壤养分及微生物量分布特征,选取研究区具有代表性的苹果(Malus pumila)-大豆(Glycine max)间作系统为研究对象,对间作系统0~60 cm 土层、0~300 cm水平距离范围内的土壤养分和微生物量进行了测定,并与大豆单作、苹果单作进行对比.结果表明:辽西北沙地苹果与大豆...  相似文献   

10.
桑树-大豆间作对盐碱土碳代谢微生物多样性的影响   总被引:9,自引:0,他引:9  
针对桑树-大豆间作可缓解盐碱土危害的特点,利用BiologTM技术研究了桑树-大豆间作对盐碱土作物根际碳代谢微生物多样性的影响.结果表明:表征土壤微生物代谢活性的平均颜色变化率(AWCD)在桑树-大豆间作下明显高于桑树单作和大豆单作,其中间作大豆的AWCD最高,单作桑树最低.桑树-大豆间作的土壤微生物均匀度指数高于单作,而土壤微生物的多样性指数和优势度指数在间作和单作之间差异不显著,说明桑树-大豆间作改变了盐碱土根际微生物群落结构组成,提高了根际微生物群落多样性.主成分分析表明,桑树-大豆间作和单作下土壤微生物的碳源利用模式出现分异,主要碳源为糖类、羧酸和聚合物类物质等.盐碱土pH和盐度是制约微生物群落多样性的主要因素,间作有效降低了土壤pH和盐度,促进了土壤微生物群落多样性的提高.  相似文献   

11.
The main objective of the present study was to investigate phosphorus (P) dynamics in the rhizosphere of durum wheat (Triticum turgidum durum L.) and common bean (Phaseolus vulgaris L.) grown in monocropping and intercropping systems with nitrate supply. Wheat and common bean were grown either alone or in association in a cropping device with a thin (1 mm) soil layer sandwiched between large root mats. Wheat intercropped with common bean exhibited a 33% increase in shoot biomass and a 22% increased root biomass, without significantly affecting common bean growth. After 12 days of culture, rhizosphere pH decreased by 1.66 and 1.13 units in monocropping system of common bean and intercropping system, respectively. Wheat increased intercropped common bean proton release by 36% compared with monocropped beans. Common bean and wheat exhibited different behaviors in rhizosphere P dynamics. Monocropped wheat decreased Resin-P, NaHCO3-P and NaOH-P in its rhizosphere by 24, 96 and 10%, respectively. However, NaHCO3-P and NaOH-P were increased by 61 and 10% in the rhizosphere of intercropping. Almost all values about P fraction in intercropping system were between those in monocropped common bean and monocropped wheat. Through taping different P fraction, different plants species possibly can alleviate competition for phosphorus in intercropping system.  相似文献   

12.
Experiments with bacterial wilt (Pseudomonas solanacearum) race 3 showed that the practice of intercropping potato with maize or haricot beans markedly reduced the incidence and rate of disease development in the potato crop. This reduction in disease was considered to be an effect of the increased distances between individual potato plants, their spatial arrangement and the presence between potato plants of root systems of other plant species, all of which resulted in a reduction in plant-to-plant transmission, via the roots. The lower potato plant population associated with intercropping resulted in a slower rate of inoculum build-up in the soil and the presence of an intercrop further markedly reduced the inoculum build-up. Where farmers retain tubers for seed, but where roguing of diseased plants is not practised, the isolation of plants through intercropping was considered to facilitate an efficient selection of healthy tubers.  相似文献   

13.
太子参为石竹科多年生草本植物,以根部入药,药用价值高,市场需求大,但其栽培过程中存在严重的连作障碍问题,连作导致产量品质严重下降,病虫害猖獗,探索太子参连作障碍形成的机制及其消减措施意义重大.本研究以广泛栽培的“柘参2号”为试验材料,采用土壤农化分析、高效液相色谱(HPLC)分析、荧光定量PCR(qPCR)等技术对不同连作年限或不同消减措施下太子参根际土壤的主要养分、酚酸含量动态及特异菌群变化进行分析.结果显示: 太子参连作导致产量显著下降,与正茬相比产量下降达43.5%,而水旱轮作和微生物菌肥处理可不同程度缓解其障碍效应.太子参连作土壤主要养分(如速效氮、速效磷、速效钾、全钾)未降反升,但导致土壤酸化.HPLC分析表明,太子参连作下或者随生长时期的推进,土壤酚酸类物质并未表现出明显的积累效应,膨大中期和收获期重茬土壤中大部分酚酸含量甚至低于正茬土壤.进一步荧光定量PCR分析发现,太子参连作导致前期分离筛选到的几类病原菌(如尖孢镰刀菌、踝节霉菌、Kosakonia sacchari)的绝对含量显著上升,而水旱轮作和微生物菌肥处理可有效降低3类病原菌的含量,改善微生态结构.综上认为,太子参连作障碍的发生并非由土壤养分匮乏或者酚酸持续积累直接造成,可能主要与连作下土传病原微生物的大量繁殖爆发有关,本研究结果为深入揭示太子参连作障碍的形成机制及消减修复机制提供了理论依据.  相似文献   

14.
青稞根腐病对根际土壤微生物及酶活性的影响   总被引:9,自引:0,他引:9  
李雪萍  李建宏  漆永红  郭炜  李潇  李敏权 《生态学报》2017,37(17):5640-5649
选取甘肃省卓尼县青稞种植区为研究地点,调查青稞根腐病的发病情况,并分别采集其健康植株和发病株根际的土壤,对比分析其土壤微生物生物量(碳、氮、磷)、微生物数量(细菌、真菌、放线菌)以及过氧化氢酶、蔗糖酶、脲酶、碱性磷酸酶、纤维素酶5种酶活性。结果发现,研究区10个采样点均有青稞根腐病的发生,发病率在5%—20%之间,不同地点发病率不同。根腐病的发生,会显著影响青稞根际微生物生物量,导致微生物生物量碳、氮、磷的含量发生变化,其中微生物生物量氮和磷含量整体降低,且不同采样点微生物量不同。土壤微生物数量总体呈现细菌放线菌真菌的趋势,但不同微生物对根腐病发病的响应不同,细菌和放线菌数量因根腐病的发生而减少,真菌的数量则增多;不同采样点土壤微生物数量不相同,细菌和真菌呈现区域性特征,放线菌的数量不呈现地域性。根腐病的发生还造成土壤酶活性的改变,其中蔗糖酶、脲酶、磷酸酶的含量因根腐病的发生而降低,而纤维素酶则升高,过氧化氢酶的变化没有规律。总而言之,根腐病的发生会使青稞根际土壤微生物组成发生改变,碳、氮、磷等物质代谢受到抑制,而能量代谢发生紊乱。因此,研究和防治青稞根腐病就必须重视土壤微生物及土壤酶的作用。  相似文献   

15.
【背景】三七根际微生物群落特征与其土传根腐病害密切相关,而针对自然林下根腐三七的相关研究鲜见报道。【目的】比较分析自然林下与田间根腐三七根际土壤微生物群落的组成特征,结合土壤理化性质与酶活性分析,为三七根腐病害防治与仿野生栽培提供科学依据。【方法】采集自然林下与田间根腐三七根际土壤,利用高通量测序技术,分析土壤细菌与真菌群落的物种组成与多样性,并测定土壤理化性质和酶活性。【结果】自然林下与田间根腐三七根际土壤中细菌和真菌群落组成具有明显差异,自然林下根腐三七根际土壤中担子菌门(Basidiomycota)、酸杆菌门(Acidobacteria)和疣微菌门(Verrucomicrobia)的相对丰度较高,而田间根腐三七根际土壤中子囊菌门(Ascomycota)、变形菌门(Proteobacteria)和绿弯菌门(Chloroflexi)的相对丰度较高。在属分类水平,镰刀菌属(Fusarium)是自然林下根腐三七根际土壤中的优势菌群,相对丰度为17.30%,而癣囊腔菌属(Plectosphaerella)是田间根腐三七根际土壤中的优势菌群,相对丰度为22.55%;Candidatus Ba...  相似文献   

16.
Geertz's famous hypothesis that horticulturalists practicing shifting cultivation intercrop their plots to mimic the protective structure of the tropical forest is evaluated in view of data on the structural ecology of the tropical forest and swidden plots in Amazonian Ecuador. The cultivation practices of the Siona-Secoya Indians reveal a three-fold typology of cropping patterns (high-diversity intercropping, low-diversity intercropping, and monocropping), with variation among the types in terms of plot size and distribution, cultigen inventory, structural complexity, and function. These gardens and the tropical forest are compared and analyzed in terms of morphology, ecological characteristics, and human manipulation and utilization. Gardens with high-diversity intercropping show certain similarities to the tropical forest, as Geertz's model predicts, but their highly transient structure does not function as a mature ecosystem. Furthermore, plots with low-diversity intercropping and monocropping show few similarities to the forest. Garden structure is best understood in terms of the economic utilization of tropical cultigens displaying specific habits, rather than by analogy to tropical forest physiognomy and function.  相似文献   

17.
以陕西延安黄土丘陵区5种不同植被类型(人工刺槐林、天然侧柏林、天然辽东栎林、灌丛和裸地)为研究对象,分析了土壤微生物生物量碳、氮含量、细菌和真菌的丰度变化规律及其与土壤基本化学性质的关系。结果表明:(1)4种植被类型的土壤质量较之裸地都有不同程度的改善,总体趋势:天然林地人工林地裸地;(2)土壤微生物生物量碳、氮的总体趋势:天然林地最高,人工林次之,裸地最低,且与土壤有机碳(SOC)、全氮(TN)和速效磷(AP)极显著正相关(P0.01);(3)裸地土壤的细菌丰度最低,人工刺槐林真菌含量显著低于天然辽东栎林。细菌丰度与土壤营养状况呈显著正相关(P0.05),而真菌与土壤营养无明显相关性,只与土壤pH负相关。说明在该研究区域,植被类型与土壤质量对微生物资源都具有不同程度的作用。  相似文献   

18.
云南省魔芋与玉米多样性栽培控制魔芋软腐病   总被引:6,自引:0,他引:6  
在云南省富源县魔芋与玉米多样性栽培区设置田间试验,分析了魔芋软腐病的发病规律、植株的生长情况及发病植株病原菌的分离频率。结果表明:魔芋与玉米轮作是控制魔芋软腐病的主要措施,它可以显著降低魔芋软腐病的死亡率,且将发病高峰期延迟1个月,轮作条件下间种控病效果比单种提高59%,间种茎基部带菌率显著低于单种;间作体系内不同栽培行植株株高差异显著,发病率差异不显著,但行间发病植株欧文氏杆菌的分离频率存在显著差异,散叶期和换头期根部和茎基部病原菌分离频率与行间距呈正相关。因此,玉米魔芋轮作间种互作条件下对软腐病的防治效果最好,间作系统内部玉米对魔芋病原菌具有一定阻隔效应。  相似文献   

19.
A field experiment was conducted to study the phytoremediation of phthalic acid esters (PAEs) by legume (alfalfa, Medicago sativa L.)-grass (perennial ryegrass, Lolium perenne L. and tall fescue, Festuca arundinacea) intercropping in contaminated agricultural soil at one of the largest e-waste recycling sites in China. Two compounds, DEHP and DnBP, were present in the soil and in the shoots of the test plants at much higher concentrations than the other target PAEs studied. Over 80% of ‘total’ (i.e., all six) PAEs were removed from the soil across all treatments by the end of the experiment. Alfalfa in monoculture removed over 90% of PAEs and alfalfa in the intercrop of the three plant species contained the highest shoot concentration of total PAEs of about 4.7 mg kg?1 DW (dry weight). Calculation of phytoextraction efficiency indicated that the most effective plant combinations in eliminating soil PAEs were the three-species intercrop (1.78%) and the alfalfa monocrop (1.41%). Phytoremediation with alfalfa was effective in both monoculture and intercropping. High bioconcentration factors (BCFs) indicated the occurrence of significant extraction of PAEs by plants from soil, suggesting that phytoremediation may have potential for the removal of PAEs from contaminated soils.  相似文献   

20.
To gain a better understanding of the mechanisms of improvement of iron nutrition of peanut (Arachis hypogaea L.) intercropped with maize (Zea mays L.) in calcareous soil, both greenhouse and field experiments were conducted to investigate the rhizosphere (phytosiderophores) effects from maize, barley, oats and wheat with different phytosiderophores release rates on iron nutrition and other micronutrients in calcareous soil. Six cropping treatments were examined in a greenhouse experiment: peanut grown separately in monoculture, normal peanut/maize intercropping (two genotypes: Danyu13, Zhongdan12), peanut/barley intercropping, peanut/oats intercropping, and peanut/wheat intercropping. Additionally, we investigated in a field experiment the same five cropping systems as the greenhouse experiment (maize/peanut intercropping not including Zhongdan12). Our results show that the chlorophyll and active Fe concentrations in the young leaves of the peanut in the intercropping system with different gramineous species were much higher than those of the peanut in monoculture. In greenhouse conditions, the Fe concentration in the shoots of peanut plants grown in the intercropping systems of two maize genotypes separately were 1.40–1.44, 1.47–1.64 and 1.15–1.42 times higher respectively than those of peanut plants grown in monocropping at 55, 60 and 70 days. In particular, the Fe concentration in shoots of peanut plants grown in the intercropping systems of barley, oats and wheat were not only higher than those in monocropping but also higher than those in peanut intercropped cropping with maize. In the field, the concentration of Fe in shoot of intercropped peanut plants in rows 1–3 from gramineous species were significantly higher than in monocropping at the flowering stage. Simultaneously with iron nutrition variation in peanut, Zn and Cu concentrations of intercropped grown peanut increased significantly compared to those in monocropping in the greenhouse experiment, and different intercropping treatments generally increased the Zn and Cu content in the shoot of peanut in the field. Systemic mechanisms may be involved in adaptation to nutrient stresses at the whole plant level. The study suggests that a reasonable intercropping system of nutrient efficient species should be considered to prevent or mitigate iron and zinc deficiency of plants in agricultural practice.  相似文献   

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