Responses of Two Contrasting Genotypes of Rice to Brown Planthopper

Abstract

Rice (Oryza sativa L.) and brown planthoppers (BPH) (Nilaparvata lugens Stål) provide an ideal system for studying molecular mechanisms involved in the interactions between plants and phloem-feeding insects. The phenotypic responses and changes in transcript profiles of seedlings representing two rice cultivars differing in resistance to the BPH were analyzed. In the BPH-compatible (susceptible) cv. MH63, BPH feeding reduced three examined plant growth parameters (leaf area expansion, height increases, and dry weight increases) and photosynthetic rates of the leaves. In the BPH-incompatible (resistant) cv. B5, BPH feeding caused slight reductions in protein and sucrose contents, but the plants maintained their photosynthetic activity and grew normally. A cDNA microarray containing 1,920 suppression subtractive hybridization clones was used to explore the transcript profiles differences in the two cultivars under control and BPH-feeding conditions. In total, 160 unique genes were detected as being significantly affected by BPH feeding in rice plants, covering a wide range of functional categories, and there were 38 genes that showed the similar transcript pattern in both genotypes. The physiological responses and transcript profiles of plants represented in both genotypes suggested that multiple pathways might be involved in reprogramming of BPH-infested rice plants. The differences in transcript levels between the compatible and incompatible interactions revealed in this study were not only the reaction of resistance and susceptibility but also reflections of different damage rates and genotypic backgrounds of the rice cultivars.

Herbivore-Induced Callose Deposition on the Sieve Plates of Rice: An Important Mechanism for Host Resistance

“…There is now considerable evidence to suggest that induced defenses are effective and have low fitness costs. Several studies have revealed that gene expression profiles in rice are reorganized in response to BPH feeding Yuan et al, 2005;Park et al, 2007;Wang et al, 2008). Such reorganization has been well documented in other plant-herbivore systems, supporting the hypothesis that inducible defenses contribute to rice resistance to the BPH.…”

“…In contrast, the expression of genes related to the flavonoid pathway, aromatic metabolism, and the octadecanoid pathway are mostly unchanged or down-regulated. This indicates that BPH feeding induces plant responses associated with a JA-independent pathway and cross talk with responses related to abiotic stress, pathogen invasion, and phytohormone signaling pathways Wang et al, 2005Wang et al, , 2008Yuan et al, 2005). Many studies have reported the effects of BPH feeding on physiological properties and metabolic changes in rice plants (Cagampang et al, 1974;Qiu et al, 2004).…”

“…To date, 19 BPH resistance genes in rice have been reported and several have been used in rice breeding programs Jena et al, 2006;Zhang, 2007). Various molecular techniques, including suppression subtractive hybridization, northern blotting, and cDNA array analysis, have been used to study rice responses to BPH feeding Wang et al, 2005Wang et al, , 2008Yuan et al, 2005;Park et al, 2007). BPH feeding is thought to result in a reorganization of the gene expression profile of rice and most of the strongly regulated genes are associated with metabolism, cell defense, cellular transport, cellular communication, or signal transduction and the biogenesis of cellular components.…”

The rice <i>GRH2</i> and <i>GRH4</i> activate various defense responses to the green rice leafhopper and confer strong insect resistance

“…Gene expression profiles in response to BPH infestation have been analyzed by several groups; however the mechanism of BPH resistance remains unclear (Wang et al 2008. In our microarray analyses, the gene expression levels of most JA/SA synthesis-or signaling-related genes in resistant lines .…”

LOW ASSOCIATION OF Bph17 ALLELE IN LANDRACES AND IMPROVED VARIETIES OF RICE RESISTANT TO BROWN PLANTHOPPER

“…The success of MAS such as Bph17 marker depends on several factors, including genetic base of trait, degree of association between molecular marker and target gene, number of individuals analyzed, and genetic background of the target gene to be transferred (Francia et al 2005;Wang et al 2008). DNA markers such as Bph17 need to be evaluated for identifying BPH biotypes.…”