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1.
土传病害是制约我国农业可持续发展的因素之一。绿肥作为高效清洁的有机肥源,与主作物合理搭配,可有效降低主作物土传病害的发生和危害,是减少化学药剂使用的重要措施。因此,综述绿肥对土传病害的防控效果与机制,对于绿肥推广应用和土传病害绿色防控具有重要意义。绿肥影响作物土传病害的研究主要集中于土传真菌病害和线虫病害,且大多数研究表明,绿肥可通过增强主作物整体抗病水平,对病原菌的化感抑制作用和改善土壤理化性质,增加土壤微生物中拮抗菌多样性和丰富度等,显著降低主作物土传病害发病率和严重程度。然而,绿肥影响主作物病害的作用机制研究不够深入,绿肥-主作物搭配模式和绿肥调控主作物病害的社会经济学效益仍需探究。同时,加强绿肥-主作物病害一体化防控及绿肥与根际促生菌、生防菌等其他有机改良剂或与适当的化学防控措施之间协同作用的研究,是未来需要加强的研究方向。 相似文献
2.
Biofumigation, as originally defined, is the use, in agriculture, of the toxicity of Brassica crop residues to control soilborne plant pathogens. This toxicity is specifically attributed to the release of toxic isothiocyanates, through the hydrolysis of glucosinolates present in the crop residues. This technique is considered a possible alternative to the use of pesticides, but field studies have generated conflicting data concerning the efficacy of biofumigation at field scale, limiting the use of this technique. Analytical studies based on a systematic approach involving evaluation of the potential effects of isothiocyanates can be used to address this problem in a rigorous manner. However, many recent studies have indicated that the mechanisms underlying biofumigation are much more complex than a simple toxic effect of residues. In this review, we dissect and discuss the problems encountered when trying to understand the variability in biofumigation efficacy and propose an integrative epidemiological approach to overcome these problems. This approach involves separating the effects of the different parameters of the system, such as the effects of different management phases of the biofumigant crop (i.e. the period of biofumigant crop growth and the phase during which crop residues are pulverised and incorporated into the soil) on the epidemiological mechanisms driving the development of an epidemic (density of primary inoculum and dynamics of disease progression). Finally, we propose new avenues of research into biofumigation in which the use of epidemiological tools and methods may improve our understanding of the factors underlying variation in the efficacy of biofumigant crops. 相似文献
3.
The vapours of allyl-isothiocyanate (AITC) were evaluated in in vitro and in vivo trials against Botrytis cinerea, a severe pathogen of strawberries. In in vitro trials AITC activity was assayed on conidial germination and mycelial growth of the fungus. The mycelium appeared less sensitive to AITC than conidia (EC50 values of 1.35 mg L−1 and 0.62 mg L−1, respectively). In addition, AITC had a fungistatic effect against the pathogen, since the values of EC50, for both parameters, increased by around 30% after AITC removal. In in vivo trials, ‘Tecla’ and ‘Monterey’ strawberries (spring-bearing and day-neutral cultivars, respectively) obtained from organic production and naturally infected by B. Cinerea, were exposed for 4 h in an atmosphere enriched by pure AITC or derived from defatted seed meals of Brassica carinata (0.1 mg L−1, in a 0.1 m3 treatment cabinet). After 2 days at 0 °C and another 3–4 days at 20 °C, the fruit were evaluated for grey mould infections. The AITC treatment reduced the decay caused by the pathogen by over 47.4% up to 91.5%, significantly different from the untreated fruit. No significant differences were found between synthetic and glucosinolate-derived AITC. Residue analysis performed on fruit at the end of storage (7 d after treatment) showed values lower than 1 mg kg−1. Total phenolic content and antioxidant capacity estimated in treated and untreated strawberries showed no significant difference between control and AITC treated fruit. Our results show it is possible to reduce the incidence of postharvest grey mould on strawberries with a treatment of AITC (0.1 mg L−1) for 4 h, opening a potential application of biofumigation in the postharvest control of B. cinerea in strawberry. 相似文献
4.
A greenhouse experiment was performed to study the effectiveness of the application of organic amendments followed by soil plastic mulching for control of Phytophthora capsici in temperate climate regions. The organic amendments were i) a non-composted mixture of sheep manure and chicken litter; ii) a semicomposted mixture of horse manure and chicken litter, and iii) Brassica carinata pellets + Sinapis alba as fresh green manure. In particular, we studied the effect of treatments on P. capsici oospore survival, disease incidence and soil properties. The treatment with B. carinata + S. alba resulted in a 93% reduction in disease incidence. The application of the semicomposted and non-composted mixture followed by soil plastic mulching caused 86 and 65% reduction, respectively, in disease incidence due, at least partially, to a decrease in oospore viability, the production of NH3 and an increase in soil microbial activity. Significantly higher values of dehydrogenase, β-glucosidase, urease and acid and alkaline phosphatase activities were detected in treated soils, possibly resulting in pathogen suppression. The application of organic amendments followed by soil plastic mulching can be a good option for control of P. capsici in protected pepper crops under temperate climate. 相似文献
5.
Hua Wu Chao-Jun WangXiao-Wei Bian Shui-Yun ZengKai-Chun Lin Bo WuGuo-An Zhang Xing Zhang 《Crop Protection》2011,30(1):33-37
Isothiocyanates (ITCs), a series of new nematicides of the -NCS group, were evaluated for their efficacy against root-knot nematode Meloidogyne javanica. Of the compounds tested, AllylITC, AcITC, EtITC, BzTC, BzITC, 1-PEITC and 2-PEITC showed in vitro irreversible nematicidal activity against second-stage juveniles of M. javanica, following exposure for 72 h at concentrations as low as 5 μg mL−1. When exposed to AllylITC, AcITC and EtITC at lower concentrations, motile juveniles also became irreversibly immobile in 3 days, with a LC50 value at 2.76, 2.53 and 3.05 μg mL−1, respectively. In the pot experiments, 1.0 ml AllylITC and 1.1 ml AcITC per kg of soil controlled M. javanica, similarly to or better than metam sodium at its recommended dose. Similar results were obtained in the field experiments using 1.0 kg AllylITC or 1.0 kg AcITC ha−1. Based on the results of this study, AllylITC and AcITC have potential to be used as new bio-fumigant nematicides. 相似文献
6.
A method for the eradication of Clavibacter michiganensis subsp. michiganensis was tested for its efficacy in three experiments carried out in the laboratory and greenhouse. In the first experiment, peat moss and sand mix in pots was amended with fresh tomato debris which was either artificially infected with the pathogen, or was not amended. Pots were enclosed in plastic bags or left open. Two temperatures (25 °C and 45 °C) were tested over a 6-week period. The pathogen was not detected in the amended soil after 4 weeks treatment at 45 °C, but was not eradicated after treatments in open pots at 25 °C.In the second experiment, the survival of C.m. michiganensis in either artificially infested soil or in artificially infected tomato plants was studied to determine the behaviour of the pathogen under these conditions. Strains of saprophytic bacteria in the genera Bacillus, Paenibacillus and Brevibacillus were identified under the experimental conditions. In vitro antagonism between Bacillus subtilis and C.m. michiganensis was observed. Finally, the recovery of C.m. michiganensis introduced into disinfected substrate was determined. Survival of C.m. michiganensis in plates artificially inoculated with substrate was greatly reduced after a 4-week treatment at 25 °C, or after 1 week at 45 °C.C.m. michiganensis remained pathogenic on plant tissue after 4 weeks of either thermal treatment.It is important to take these results into account with regard the effect of different soil disinfection techniques or ecological alternatives such as biofumigation, solarization, and the addition of organic matter, as well as for integrated pest management systems. 相似文献
7.
Factors that impact on the ability of biofumigants to suppress fungal pathogens and weeds of strawberry 总被引：1，自引：0，他引：1
S.W. Mattner I.J. Porter R.K. Gounder A.L. Shanks D.J. Wren D. Allen 《Crop Protection》2008,27(8):1165-1173
This research aimed at identifying factors that improve the efficacy of biofumigants for soil disinfestation against strawberry (Fragaria×ananassa) pathogens and weeds. In laboratory bioassays, volatiles released from the macerated roots of a Brassica rapa/Brassica napus biofumigant crop were six times more effective at suppressing the growth of the strawberry pathogen Rhizoctonia fragariae than shoots. Furthermore, the toxicity of the volatiles from the biofumigant crop to R. fragariae increased as plant developmental stage progressed. These results related to the release of higher quantities and greater diversity of isothiocyanates (ITCs) from the roots of mature biofumigant plants than from their shoots. Separate bioassays showed that volatiles from the biofumigant crop suppressed the growth of six different soil-borne pathogens (Alternaria alternata, Colletotrichum dematium, Cylindrocarpon destructans, Fusarium oxysporum, Pythium ultimum, Phytophthora cactorum, and R. fragariae) of strawberry and seven Trifolium spp. (clover) weeds. The suppression of Trifolium spp. by biofumigant volatiles did not relate to their seed size, but might relate to their hard-seededness or genotype. In the field, rotary incorporation of the biofumigant crop did not produce detectable levels of ITCs in soil; reduce the survival of the strawberry pathogens, P. cactorum and C. destructans; or affect populations of culturable soil microflora. Yet, it suppressed the growth of emerging weeds by 40% and the growth of P. cactorum by 20%. We hypothesise that allelochemicals other than ITCs, such as nitriles, or other biological mechanisms might also play a role in biofumigation. A key to improving the efficacy of biofumigation in the field seems to lie in the development of application technologies that can macerate and incorporate biofumigants evenly in soils, in addition to incorporating biofumigants under optimal edaphic conditions for release of ITCs. 相似文献
8.
Nematode pests parasitise and cause substantial crop yield and quality losses to a wide range of crops worldwide. To minimize such damage, the exploitation and development of alternative nematode control strategies are becoming increasingly important, particularly as a result of global efforts to conserve the ozone layer as well as our soil and water substrates. Inclusion of Brassicaceae crops in cropping systems is one such alternative and has been demonstrated in most cases to be effective in managing the top-three rated economically important nematode pests, viz. root-knot (Meloidogyne), cyst (Heterodera and Globodera) and lesion (Pratylenchus) nematodes as well as others. In the past nematode pests were and still are generally managed successfully by the use of synthetically-derived nematicides, which are progressively being removed from world markets. However, fragmented and limited information about the use of Brassicaceae crops as a nematode management tool exists in various countries. The need thus arose to summarize, compare and discuss the vast amount of information that has been generated on this topic in a concise article. This paper therefore represents a comprehensive, practical and critical review of the use and effect(s) of Brassicaceae-based management strategies and the biofumigation and cover-crop/rotation characteristics of Brassicaceae in reducing nematode-pest population levels in global cropping systems. 相似文献
9.
Hanna Friberg Véronique Edel-Hermann Nadine Gautheron Vincent Faloya Christian Steinberg 《Soil biology & biochemistry》2009,41(10):2075-7890
Two fungal plant pathogens, Rhizoctonia solani AG 2-2 and Fusarium oxysporum f.sp. lini, were studied in relation to general responses of soil fungi and bacteria following incorporation of Brassica juncea. Our aim was to understand to what extent the changes in the biological and physicochemical characteristics of the soil could explain the effects on the studied pathogens and diseases, and to determine the temporal nature of the responses. Short-term effects of mustard incorporation (up to 4 months) were investigated in a microcosm experiment, and compared with a treatment where composted plant material was incorporated. In a field experiment, the responses were followed up to 11 months after removal or incorporation of a mustard crop. In general, responses in the variables measured changed more after incorporation of fresh mustard material than after addition of similar amounts of composted plant material (microcosms) or after removal of the mustard crop (field). The soil inoculum potential of R. solani AG 2-2 decreased directly after incorporation of mustard, but increased later to disease levels above those in the untreated soil. Neither of these effects could be explained by changes in the population density of R. solani AG 2-2. Fusarium spp. were less influenced, although an increase in the suppressiveness to Fusarium wilt was observed after mustard incorporation as compared with the treatment where mustard was removed. The microbial responses to mustard incorporation were more pronounced for bacteria than for fungi. After an initial substantial increase, the bacterial density decreased but remained above the levels in the control treatment throughout the experimental periods. The bacterial community structure was modified up to 8 months after mustard incorporation. We conclude that incorporation of fresh mustard influences soil microbial communities, especially the bacteria, and has a potential to control the pathogenic activity of R. solani 2-2 on a short-term perspective. The time dependency in microbial responses is important and should be taken into consideration for the evaluation of the potential of Brassicas to control plant disease on a field scale. 相似文献
10.
花椒籽饼熏蒸对番茄根结线虫的防效及作用机理 总被引：1，自引：0，他引：1
采用温室盆栽试验、GC-MS分析方法以及根结线虫二龄幼虫离体触杀试验,研究了花椒籽饼对番茄根结线虫的防治效果及其作用机理。结果表明:土壤生物熏蒸处理30d后,随花椒籽饼施用量的增加,土壤中全氮、全磷、全钾、碱解氮、速效钾含量均显著增加,土壤p H值呈上升趋势,速效磷含量则下降;番茄定植30d后,随花椒籽饼施用量的增加,植株根结指数逐渐下降,株高、茎粗则呈现先增加后降低的趋势;不同浓度的花椒籽饼浸提液均对根结线虫虫卵孵化产生抑制作用,且随浸提液浓度的增加抑制作用增强;GC-MS分析结果表明,花椒籽饼中含有28种挥发性物质,其中具有杀线作用的D-柠檬烯和芳樟醇两种物质之和占总成分的13.53%;不同浓度的D-柠檬烯和芳樟醇均能够有效抑制根结线虫二龄幼虫的活性,且表现出明显的浓度效应。综上,适量施用花椒籽饼不仅能够改善土壤理化性质,促进番茄植株生长,而且能够有效地抑制根结线虫的发生,其杀线机理主要归因于花椒籽饼中含有丰富的D-柠檬烯和芳樟醇。 相似文献