02409nam a2200289 a 450000100080000000500110000800800410001910000190006024501500007926000230022930000180025250001010027052015230037165000130189465000170190765000250192465000260194965000250197565000150200065000090201565300210202465300210204565300130206665300120207965300120209170000160210314453142013-03-07       1984    bl uuuu     u0uu1 u    #d1 aDALL'AGNOL, A.  aResponse of five plant species to three densities of Meloidogyne incognita, M. javanica, M. arenaria according to three parameters of evaluation.  a[S.l.: s.n.]c1984  anao paginado.  aTrabalho apresentado: First International Congress of Nematology, Guelph, Ontario, Canada, 1984.  aTo determine the relative efficiency of a quick visual gall score method as compared to other evaluation techniques in identifying the degree of resistance of black beans, cotton, sunflower, tomato and soybean, plants were inoculated with 1, 2 and 5 x 104 eggs and larvae of Meloidogyne incognita, M. javanica and M. arenaria. Plants varied widely in their susceptibility to the three nematode specis. With few exceptions, plants rated as resistant or susceptible based on the visual gall score method, had similar reactions as compared to egg mass index or total nematode counts. correlation coefficients were highly significant. The final nematode population increased as the inoculum density increased, but the rate of reproduction decreased as the initial nematode population increased. Highly resistant plants did not react to five fold increase in inoculum density. Percentage of nematodes collected from the soil among tested plants, ranged from 16 to 46 (M. incognita), 23 to 58 (M. javanica) and 12 to 79% (M. arenaria). These percentages were particularly high for cotton (43, 58 and 79%, respectively, for M. incognita, M. javanica and M. arenaria). In general, the highest and lowest percenages in the soil were observed among highly resistant and highly susceptible plants, respectively. Results indicate thate the visual gall score is a reliable method to evaluate plant genotypes for root knot nematode resitance and is very useful to screen large number of genotypes due to its simplicity and rapidity.  abreeding  aMelhoramento  aMeloidogyne Arenaria  aMeloidogyne Incognita  aMeloidogyne Javanica  aNematóide  aSoja  aCultivar Andrews  aCultivar Mineira  aNematode  aSoybean  aVariety1 aANTONIO, H.