Powdery mildew disease, one of the major diseases of soybean in Vietnam was caused by Microsphaera diffusa. SSR (Simple sequence repeats) marker, because of their co-dominance, polymorphic and stability have been wildely used to measure genetic diversity in crop. In the present study, genetic basis of 36 soybean genotypes varying in powdery mildew resistance was studied using 14 SSR markers. A total of 61 alleles with an average of 4,36 allele/locus, which indicated hight genetic diversity of the studied genotypes. PIC value of each marker ranged from 0 (Sat_396, Satt183, Sat_298) to 0,711 (Sat_224) with an average of 0.364 which shown high genetic diverrsity among the studied genotypes. At genetic similarity coefficient of 0.75, 36 soybean genotypes divided into 8 distint groups. Group 1 and group 2 included 21/25 genotypes which was resistant to powdery mildew. Groups 1, 2, 4, 5 and 8 include powdery mildew resistance genotypes.

Seed treatment using metallic nanoparticles to stimulate germination and improve crop yields has been published and widely applied in agriculture production. To assess the safety of such methods on plants, the effectiveness and safety of the treatment of soybean Glycine max L. DT12 seeds with cobalt nanoparticles (nCo) before sowing were investigated. Seeds of soybean cultivar DT12 were treated with nCo at two different concentrations (0.165 and 1.65 mg/kg seed) before sowing. Germination rate, growth speed, soybean yield and bean nutrient components were examined throughout a season. Results implied that at a concentration of 0.165 mg/kg, nCo significantly increased germination rates, plant heights, total pods per plant, number of pods having 3 seeds, and crop productivity compared to both the control and seeds treated with a highter concentration of 16.5 mg per kg of seed. However, no significant differences were found between treatments in terms of growth level and seed nutrient contents, including moisture, ash content, mineral (K, Mg and Fe) and crude protein components. In seeds treated with higher concentration, the Ca content was dramatically lower than that of the control and seeds treated with a low concentration, but bean quality was not affected. This study contributes to the effective and sustainable application of nanomaterials in Vietnamese agriculture.

Soybean, Glycine max, is an important crop in Vietnam. The yield of this crop can be reduced up to 35% due to powdery mildew (PMD), a common disease in soybean. In the present study, we analyzed the PMD resistance of soybean accessions for two seasons and subsequently used SSR markers to determine the genetic diversity of these accessions. Twenty three SSR markers were used to amplify polymorphic SSRs from all of these genotypes in eighteen linkage groups. By analyzing 69 alleles for all accessions, the number of alleles ranged from 2 to 7 with an average of 4.3 at each locus. The polymorphic information content of each marker ranged from 0.104 (Sct_187) to 0.818 (Satt009) with a mean of 0.578. The pairwise coefficients of genetic similarity (Jaccard's coefficients) among all genotypes ranged from 0.28 to 0.98 with an average of 0.61. Unweighted pair-group method arithmetic average and principal coordinate analysis separated the accessions into two major groups containing 28 and 6 accessions. The results of this study suggested some appropriate parent pairs based on genetic relationship as well as the yield and resistant characteristics of soybean accessions for breeding soybean accessions with PMD resistance and high yield characteristic.