• Title/Summary/Keyword: Crop plant

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Expression of BrD1, a Plant Defensin from Brassica rapa, Confers Resistance against Brown Planthopper (Nilaparvata lugens) in Transgenic Rices

  • Choi, Man-Soo;Kim, Yul-Ho;Park, Hyang-Mi;Seo, Bo-Yoon;Jung, Jin-Kyo;Kim, Sun-Tae;Kim, Min-Chul;Shin, Dong-Bum;Yun, Hong-Tai;Choi, Im-Soo;Kim, Chung-Kon;Lee, Jang-Yong
    • Molecules and Cells
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    • v.28 no.2
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    • pp.131-137
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    • 2009
  • Plant defensins are small (5-10 kDa) basic peptides thought to be an important component of the defense pathway against fungal and/or bacterial pathogens. To understand the role of plant defensins in protecting plants against the brown planthopper, a type of insect herbivore, we isolated the Brassica rapa Defensin 1 (BrD1) gene and introduced it into rice (Oryza sativa L.) to produce stable transgenic plants. The BrD1 protein is homologous to other plant defensins and contains both an N-terminal endoplasmic reticulum signal sequence and a defensin domain, which are highly conserved in all plant defensins. Based on a phylogenetic analysis of the defensin domain of various plant defensins, we established that BrD1 belongs to a distinct subgroup of plant defensins. Relative to the wild type, transgenic rices expressing BrD1 exhibit strong resistance to brown planthopper nymphs and female adults. These results suggest that BrD1 exhibits insecticidal activity, and might be useful for developing cereal crop plants resistant to sap-sucking insects, such as the brown planthopper.

Molecular Mechanism of Plant Growth Promotion and Induced Systemic Resistance to Tobacco Mosaic Virus by Bacillus spp.

  • Wang, Shuai;Wu, Huijun;Qiao, Junqing;Ma, Lingli;Liu, Jun;Xia, Yanfei;Gao, Xuewen
    • Journal of Microbiology and Biotechnology
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    • v.19 no.10
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    • pp.1250-1258
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    • 2009
  • Bacillus spp., as a type of plant growth-promoting rhizobacteria (PGPR), were studied with regards promoting plant growth and inducing plant systemic resistance. The results of greenhouse experiments with tobacco plants demonstrated that treatment with the Bacillus spp. significantly enhanced the plant height and fresh weight, while clearly lowering the disease severity rating of the tobacco mosaic virus (TMV) at 28 days post-inoculation (dpi). The TMV accumulation in the young non-inoculated leaves was remarkably lower for all the plants treated with the Bacillus spp. An RT-PCR analysis of the signaling regulatory genes Coil and NPR1, and defense genes PR-1a and PR-1b, in the tobacco treated with the Bacillus spp. revealed an association with enhancing the systemic resistance of tobacco to TMV. A further analysis of two expansin genes that regulate plant cell growth, NtEXP2 and NtEXP6, also verified a concomitant growth promotion in the roots and leaves of the tobacco responding to the Bacillus spp.