Transgenic indica rice resistant to sap‐sucking insects

Abstract

SummaryAgrobacterium-mediated genetic transformation has been optimized in indica rice susceptible to sap-sucking insects, viz., brown planthopper (BPH) and green leafhopper (GLH). Snowdrop lectin gene ( gna) from Galanthus nivalis, driven by phloem-specific rice-sucrose-synthase promoter, along with herbicide resistance gene (bar) driven by CaMV 35S promoter, was employed for genetic transformation. Embryogenic calli -after cocultivation with Agrobacterium strain LBA4404 harbouring Ti plasmid pSB111-bar-gnawere selected on the medium containing phosphinothricin. PCR and Southern blot analyses confirmed the stable integration of both the genes into genomes of transgenic (T 0 ) rice plants. Northern and Western blot analyses revealed the expression of gna in the transgenic plants. In the T 1 and T 2 generations, the gna and bar transgenes showed co-segregation at a ratio of 3 : 1. Plant progenies expressing gna, in T 1 and T 2 , exhibited substantial resistance against BPH and GLH pests. This is the first report dealing with transgenic indica rice exhibiting high resistance to both insects.

Shared flowering phenology, insect pests, and pathogens among wild, weedy, and cultivated rice in the Mekong Delta, Vietnam: implications for transgenic rice

“…A few examples of transgenes for pest protection that have already been used in rice transformation and could become available in Vietnam and elsewhere include Bt and cowpea trypsin inhibitor genes for resistance to lepidopteran larvae (High et al, 2004;Huang et al, 2005), lectin genes for resistance to sucking insects (Nagadhara et al, 2003;Saha et al, 2006), chitinase or allene oxide synthase genes for resistance to fungal diseases (Datta et al, 2001;Mei et al, 2006), and trangenes for resistance to bacterial blight (Zai et al, 2004). Other transgenic traits that could be released separately or in combination with various types of pest resistance include resistance to commonly used herbicides, greater tolerance of abiotic stresses, and enhanced production of pro-vitamin A (e.g., Lu and Snow, 2005).…”

Computational and Real-Time RT-PCR Expression Analyses of Garlic Lectin Gene

“…Garlic lectins remained the focus of various transformation studies. Studies such as pyramided rice lines (Foissac et al, 2000;Nagadhara et al, 2003); marker genefree transgenic tobacco (Bharathi et al, 2011); chickpea (Chakraborti et al, 2009); rice (Yarasi et al, 2008) show effectiveness of lectins against sucking insect population. The efficacy of snowdrop (G. nivalis) and garlic lectins have been studied against phloem feeding Aphis craccivora, cotton aphids A. gossypii (Sauvion et al, 1996), red spider mite of tea (Roy et al, 2008), cotton leafworm and sapsucking planthoppers (Powell, 2001).…”

Plant‐insect interactions: what can we learn from plant lectins?

“…Transgenic rice plants expressing GNA showed resistance to Nephotettix virescens and N. lugens (Foissac et al, 2000;Nagadhara et al, 2003). In both studies, the survival of nymphs on GNA-expressing plants was significantly reduced (up to 50%).…”

“…In both studies, the survival of nymphs on GNA-expressing plants was significantly reduced (up to 50%). Honeydew production was reduced on the GNA-expressing lines (Foissac et al, 2000) and Nagadhara et al (2003) recorded less plant damage on the transgenic plants, both indicating reduced feeding. But no GNA was detected in the honeydew.…”

“…Rice plants have been genetically transformed by several research groups to express lectins either constitutively or specifically in the phloem (Foissac et al, 2000;Nagadhara et al, 2003;Saha et al, 2006b;Yarasi et al, 2008). Foissac et al (2000) did not detect a significant difference in honeydew production of N. virescens (rice green leaf hopper) nor of N. lugens (brown plant hopper) when fed GNA-containing transgenic rice as compared to wild type control plants.…”