The yellow mosaic viruses (YMV) infecting legumes are considered to be the most devastating begomoviruses as they incite considerable yield loss. The yellow discoloration of pods and seeds of infected plants and symptom emergence in the very first trifoliate leaf of the plants in the field were suggestive that the virus may be seed borne, which was investigated in the present study. The distribution of the virus in various parts of the seeds of black gram (Vigna mungo L. Hepper) plants naturally infected in the field was determined by polymerase chain reaction (PCR), Southern blot analysis, and sequencing. Nucleotide sequencing of the PCR amplicons from the seed parts from groups of ten seeds revealed the presence of mung bean yellow mosaic virus (MYMV) in the seed coat, cotyledon, and embryonic axes. The presence of virion particles was confirmed through double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) and immunosorbent electron microscopy (ISEM) even in a single whole seed. In confocal microscopy, positive fluorescent signals were obtained using coat protein gene-specific primers in the embryonic axes. However, in the growth tests performed with the same batch of seeds, there was no symptom development in the seedlings though the virus (both DNA A and B components) was detected in 32 % of tested seedlings. In this study, the MYMV was detected in seed coat, cotyledon, and embryo. This study revealed that the MYMV is a seed-borne virus.

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O resíduo de azoxistrobina em mangas foi determinado por cromatografia líquida de alta performance (HPLC). O resíduo foi extraído com acetonitrila e purificado tanto por extração líquido-líquido (LLE) quanto por extração de fase sólida (SPE). A análise cromatográfica foi realizada em uma coluna ODS2 com fase móvel acetonitrila: água 80:20 v/v e detecção por UV em 255 nm. As recuperações médias e limites de determinação foram iguais a 85.57 % e 0.004 µg g -1 de amostra, respectivamente. Os resultados reveleram que a meia vida da azoxistrobina foi igual a um dia, para a dose recomendada. Portanto, não há problemas de contaminação da cadeia alimentar e do meio ambiente pela adição de azoxistrobina em mangas.Azoxystrobin residue was determined in mango fruits using high performance liquid chromatography (HPLC). Residues of azoxystrobin were extracted with acetonitrile and purified by both liquid liquid extraction (LLE) and solid phase extraction (SPE) clean up. The HPLC analysis was carried out on ODS2 column with acetonitrile: water (80:20 v/v) as the mobile phase with UV detection at 255 nm. The rate of average recoveries and limits of determinations were 85.57 % and 0.004 µg per g of sample, respectively. The results revealed that the half life of azoxystrobin in mango fruit was one day for recommended dose, hence no concern regarding contamination of the food chain and environment by azoxystrobin

Abatract:The present study explored pathogenic and genetic variability among the eleven isolates of Rhizoctonia bataticola (Taub.) Butler from different pulse crops. Based on morphological characters, 11 isolates were categorized into three groups viz., linear, fluffy, and linear at the end with fluffy growth at the center. Isolates also showed variability in sclerotial characters (intensity and shape) and intensity of pigment synthesis. All isolates were more aggressive on the original host from which it was isolated, which was shown by the variability in pathogenic characters. RAPD-PCR analysis has shown that genetic clustering agreed with the above findings in dendrogram analysis (2 clusters A and B). The black gram root isolates showed a maximum genetic similarity of 73 % with soya bean shoot isolate. Red gram shoot isolate showed 61% genetic similarity with green gram isolates. The findings from this study confirm the variability in R. bataticola isolates from pulses, according to their pathological as well as genetic characters. In the future, variability in pathogens will determine effective management practices.

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