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The Red River Delta is one of primary banana-producing regions in Vietnam, and it has been afflicted by Fusarium wilt disease, caused by Fusarium oxysporum f. sp. cubense (Foc). This study aimed to identify Foc strains from banana-diseased samples collected from six different provinces in this region. Foc's identity was confirmed based on morphological characteristics, artificial inoculation on the Tieu hong banana cultivar, and through DNA sequencing and phylogenetic analysis of PCR products amplified by race-specific primer pairs (Foc-1/Foc-2, Foc TR4-F/FocTR4-R). Ten Foc TR4 strains were identified, including VP1(2), VP1(5), and VP2(6) strains were found in Vinh Phuc Province, ML02.2 strain in Ha Noi City, MS1T2 strain in Hung Yen province, BV03 and BV06 strains in Hai Phong City, and QG1(R), QG4(T), QH2(R) strains in Thai Binh province. This discovery underscores the importance of appropriately identifying causal pathogens for integrated pest management of Fusarium wilt disease in the Red River Delta. [ABSTRACT FROM AUTHOR]

The Pueraria mirifica plant is used as a precious material in healthcare and herbal supplement production as it is rich in phytoestrogen content. The wide cultivation gradually directs to the differences among cultivars based on their local original planting region. Besides variation in morphology, P. mirifica plants are different in phytoestrogen content. With barcoding markers located on nuclear and chloroplast, our phylogenetic analysis proved that using the group of matK, rp°C, rps16, and trnH-psbA concatenated sequences provides better discriminating power than using a single marker of common P. mirifica cultivars. Only the maximum likelihood tree based on marker combination separate P. mirifica plants from other members of the Pueraria family and separated tribes in the Fabaceae family. In addition, daidzein, genistin, and puerarin contents were recorded from the tuber of all cultivars. These results showed that some are potential cultivars for extracting phytoestrogens from the tuber. Among the five varieties studied, NA has the highest content of Daidzein and Puerarin, and TLBYT has the most difference in the sequences of rps16 and trnH-psbA and the lowest content of Puerarin, Genistin, and Daidzein. Together, qRT-PCR was performed to evaluate eight phytoestrogen biosynthesis gene expressions in leaf and tuber, in which four novel genes CHS11, CHS13, CHI2A, and UGT2 were examined for the first time in P. mirifica. These gene expressions varied depending on organs and cultivars. The differences in both the content of substances and in DNA barcodes as well as gene expression showed a clear polymorphism between varieties. The information is valuable for the selection of material sources for production. [ABSTRACT FROM AUTHOR]

<b>Background and Objective:</b> <i>Pieris rapae</i> L., is one of the most widespread and destructive pests of cruciferous plants. At present, synthetic chemical insecticide is still the main approach to control this pest despite several disadvantages to human health and the wildlife environment as well as biological resistance. To search for plants having insecticidal activity, the biological effects of two medicinal plants <i>Kaempferia galanga</i> L. and <i>Amomum subulatum </i>on <i>Pieris rapae</i> L., were investigated. <b>Materials and Methods:</b> The methanol extracts of dry rhizomes and fruits of <i>Kaempferia galanga</i> L. and <i>Amomum subulatum </i>were used to determine the mortality, feeding and oviposition deterrence of larvae and adult of <i>Pieris rapae</i> L. <b>Results:</b> <i>Kaempferia galanga</i> L. and <i>Amomum subulatum</i> exhibited insecticidal activity against <i>Pieris rapae</i> L., with LC<sub>50</sub> values of 2.11 and 11.80% (w/v), respectively. In the antifeedant test, <i>Kaempferia galanga</i> L., extract showed no significant difference with the control at the low concentration (0.5 and 1%). Whereas, with a concentration of 0.5%, <i>Amomum subulatum</i> extract demonstrated a high antifeedant effect on <i>Pieris rapae</i> L., larvae. In addition, plants treated with these two extracts reduced eggs laid by <i>Pieris rapae</i> L., in field conditions showing the oviposition deterrent properties. <b>Conclusion:</b> These results indicated that <i>Kaempferia galanga</i> L. and <i>Amomum subulatum </i>extracts have insecticidal substances against <i>Pieris rapae </i>L., which can be used for developing effective pesticides or/and oviposition deterrents for integrated pest management.