Phytodecta fornicata Brüggemann resistance mediated by oryzacystatin II proteinase inhibitor transgene

Abstract

Phytodecta fornicata Brüggemann is a serious pest of alfalfa (Medicago sativa L.) that causes significant crop loss in the Balkan peninsula of Europe. We introduced a wound-inducible oryzacystatin II (OCII) gene to alfalfa to evaluate its effect on survival of P. fornicata larvae. Feeding bioassays with second, third and fourth instars were carried out using transgenic plants that were shown to express OCII at 24 and 48 h after wounding. Second and third instars were the most sensitive to the ingestion of OCII, whereas no effects were observed with fourth instars. About 80% of the second and third instars died after 2 days of feeding on the transgenic plants as compared to 0-40% on the controls. This is the first report that demonstrates significant increase in mortality of P. fornicata on transgenic plants that express a cysteine proteinase inhibitor gene, and this knowledge should lead to the development of effective management strategies for this devastating pest of alfalfa.

Deleterious effects of plant cystatins against the banana weevil Cosmopolites sordidus

“…Zhao et al, 1996;Koiwa et al, 2000;Liu et al, 2004;Alvarez-Alfageme et al, 2007;Ninkovic et al, 2007), our data indicate a dramatic negative impact of plant cystatins on larval growth, associated with the presence of cystatin-sensitive cysteine cathepsins in midgut extracts. As suggested from studies reporting detrimental effects for the broad-spectrum inhibitor of papain-like proteases E-64 against Coleoptera, these negative effects of OsCYS1 and CpCYS1 were likely the result of a broad sensitivity of the insect digestive cathepsins to the ingested inhibitors.…”

“…Despite some promising developments (Leplé et al, 1995;Kuroda et al, 1996;Koiwa et al, 2000;Liu et al, 2004;Alvarez-Alfageme et al, 2007;Ninkovic et al, 2007), the general usefulness of plant cystatins for the control of coleopteran pests still remains to be established. These insects have developed over time effective strategies to elude the inhibitory effects of plant protease inhibitors, involving the use of complex digestive protease systems with proteases from different mechanistic classes acting in a complementary, coordinated manner (Brunelle et al, 1999;Hernandez et al, 2003;Gruden et al, 2003;Vinokurov et al, 2006a,b;Prabhakar et al, 2007); the over-expression of target proteases following cystatin ingestion to outnumber the inhibitory proteins (Cloutier et al, 2000;Ahn et al, 2004); the constitutive or diet-induced expression of cysteine cathepsins weakly sensitive to the ingested cystatin, the so-called 'cystatin-insensitive proteases' (Michaud et al, 1993(Michaud et al, , 1995aGirard et al, 1998a;Cloutier et al, 1999Cloutier et al, , 2000ZhuSalzman et al, 2003;Brunelle et al, 2004;Gruden et al, 2004;Liu et al, 2004;Koo et al, 2008); the over-expression of proteases from alternative mechanistic classes following cystatin ingestion (Zhu-Salzman et al, 2003;Brunelle et al, 2004;Rivard et al, 2004;Oppert et al, 2005); and the degradation of defensive protease inhibitors using non-target, insensitive proteases (Michaud et al, 1995b;Girard et al, 1998b;Giri et al, 1998;Gruden et al, 2003;Zhu-Salzman et al, 2003).…”

“…In this study, we assessed the potential of OC-I and other plant cystatins as possible tools for the production of transgenic banana lines resistant to the banana weevil. Several papers have been published assessing the effectiveness of plant cystatins against herbivorous Coleoptera, with conclusive results in some cases (Leplé et al, 1995;Kuroda et al, 1996;Lecardonnel et al, 1999;Koiwa et al, 2000;Alvarez-Alfageme et al 2007;Ninkovic et al, 2007) but disappointing results in other cases owing to the ability of the target insects to readily elude or even counteract the antidigestive effects of natural or recombinant inhibitors (e.g. Girard et al, 1998a,b;Cloutier et al, 1999Cloutier et al, , 2000Zhu-Salzman et al, 2003;Gruden et al, 2003Gruden et al, , 2004Ahn et al, 2004Ahn et al, , 2007Oppert et al, 2005;Koo et al, 2008).…”

Recent advances in functional genomics for sugar beet (Beta vulgaris L.) improvement: progress in determining the role of BvSTI in pest resistance in roots

“…To gain knowledge of root defense mechanisms, our laboratory has been studying the interaction of sugar beet with the sugar beet root maggot (SBRM; Tetanops myopaeformis Roder) (Puthoff and Smigocki, 2007;Smigocki et al, 2006). Root damage from SBRM feeding is a serious problem in the U.S. and Canada and leads to significant reductions in sugar yields.…”

“…The F1016 germplasm provides the highest reduction (approximately 40%) in SBRM damage ratings under field conditions. To identify root genes responsible for this resistance, we profiled root genes that are modulated by SBRM feeding in the moderately resistant F1016 and the susceptible F1010 line (Puthoff and Smigocki, 2007). More than 160 genes were identified using suppressive subtractive hybridization as an enrichment method for genes that respond to SBRM feeding.…”