Detection and differentiation of two complications of disorder and lack of podding of soybeans in the fields of Golestan and Mazandaran provinces

In order to detection and differentiation of two complications of disorder and lack of podding in soybeans, while visiting 185 soybean fields in Golestan and Mazandaran provinces, only from the summer cultivation of 17 fields from five different places in Golestan province, plants with signs of disorder and the lack of acute podding were identified and 17 samples were selected from each field and sampling was done from the leaves or stems of the mentioned plants in order to extract RNA and DNA. Then, PCR was performed to detect nepovirus using the degenerate primer of nepovirus and to detect phytoplasma using a pair of general primers and a nested PCR test. The results of electrophoresis confirmed the amplification of the 1800 bp band in the general PCR, the 1250 bp fragment in the nested PCR related to phytoplasma, and also the amplification of the 640 bp band related to a nepovirus. Besides, no band of healthy plants was observed. at the same time, tissue grafting and mechanical inoculation were performed on GPX soybean benchmark plant using the mentioned samples and two types of symptoms appeared. From the sequencing of the disordered samples (production of a small number of seeds and small pods), Tomato ring spot virus strain ep31_63026 and from the sequencing of the samples with non-encapsulation (grassiness and no formation of pods and seeds), Aster yellows phytoplasma from the 16SrI-B group were identified, which confirmed the results of the reference plant. The phylogenetic analysis of sequencing results confirmed the presence of Phytoplasma and Nepovirus only in the summer culture of samples that had symptoms of disorder and lack of podding.