02497naa a2200337 a 450000100080000000500110000800800410001910000180006024501170007826000090019550001490020452013560035365000130170965300190172265300170174165300260175865300140178465300170179865300260181565300240184165300250186565300470189065300220193765300240195965300210198370000150200470000180201970000180203770000150205577300890207016608912018-06-08       2009    bl uuuu     u00u1 u    #d1 aVILLENAVE, C.  aImpact of direct seeding mulch-based cropping systems on soil nematodes in a long-term experiment in Madagascar.  c2009  aTítulo em português: Impacto do plantio direto com cobertura vegetal nos nematódeos edáficos em experimento de longa duração em Madagasca.  aAbstract - The objective of this work was to assess the effects of conventional tillage and of different direct seeding mulch-based cropping systems (DMC) on soil nematofauna characteristics. The long-term field experiment was carried out in the highlands of Madagascar on an andic Dystrustept soil. Soil samples were taken once a year during three successive years (14 to 16 years after installation of the treatments) from a 0-5-cm soil layer of a conventional tillage system and of three kinds of DMC: direct seeding on mulch from rotation soybean-maize residues; direct seeding of maize-maize rotation on living mulch of silverleaf (Desmodium uncinatum); direct seeding of bean (Phaseolus vulgaris)-soybean rotation on living mulch of kikuyu grass (Pennisetum clandestinum). The samples were compared with samples from natural fallows. The soil nematofauna, characterized by the abundance of different trophic groups and indices (MI, maturity index; EI and SI, enrichment and structure indices), allowed the discrimination of the different cropping systems. The different DMC treatments had a more complex soil food web than the tillage treatment: SI and MI were significantly greater in DMC systems. Moreover, DMC with dead mulch had a lower density of free-living nematodes than DMC with living mulch, which suggested a lower microbial activity.  aNematoda  aCobertura viva  aCrop residue  aFuncionamento do solo  aIndicador  aLiving mulch  aNematódeos edáficos  aNematofauna do solo  aNematofauna edáfica  aPlantio direto com cobertura vegetal (DMC)  aResíduo cultural  aResíduos culturais  aSoil functioning1 aRABARY, B.1 aCHOTTE, J.-L.1 aBLANCHART, E.1 aDJIGAL, D.  tPesquisa Agropecuária Brasileira, Brasília, DFgv. 44, n. 8, p. 949-953, ago. 2009