Caracterización morfológica y molecular de cepas de Bacillus nativas de suelos de la provincia de Pichincha para biocontrol del ácaro Tetranychus urticae

Content Provider	Semantic Scholar
Author	Casanova, Narváez Cristina, Ana
Copyright Year	2015
Abstract	The goal of this research was isolate native Bacillus strains from soils and compost in the province of Pichincha in Ecuador, and to test for acaricidal effect of these isolates against Tetranychus urticae. This kind of study is pioneer in Ecuador. Bacterial counts were conducted for the 8 samples collected. The statistical analysis showed significant differences in bacterial counts (F=3,8; p < 0,05; gl=7). In total 166 isolates were obtained and they were classified into 15 morphological groups. In general there was great variation in the diversity of bacteria present in each sample and each environment. The variables evaluated were acaricide effect, inhibition of oviposition and the larvicidad action of 22 bacterial isolates. In addition to the positive control BtC and the negative control that was T3 pure medium. A total of 24 treatments were evaluated. Five replicates per treatment were done. Data at 120 and 168 hours after application of the bacterial cultures was evaluated. Of the 22 strains tested on the acaricide effect at 120 hour, isolates P1.14(B), I1.23(A), C2.4(E) and I1.5(K), showed the largest number of dead individuals, these were chosen as strains with high acaricide potential. It was concluded that P1.23 (E), C2.4(E), and I1.23(A) isolates had a negative effect on oviposition of females treated at 120 hours. The C2.4(E) and P1.23(E) strains had an effect in inhibiting nymph’s infestation at 168 hours.The positive control bacteria BtC and C2.4(E) isolate were identified by molecular sequencing as Bacillus thuringiensis serovar kurstaki, which correlates with the microscopic observations of these isolates. The sequencing of the isolate I1.5(K) resulted as the bacterium Pseudomonas aeruginosa, but this was not consistent with the phenotypic characteristics of this isolated. The isolated P1.14(A) proved to be Bacillus subtilis that matches with the phenotypical characteristics observed at 100x magnification.
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Alternate Webpage(s)	http://repositorio.usfq.edu.ec/bitstream/23000/4208/1/113819.pdf
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article