探討瘤野螟生物小種及水稻品種之抗性

Examine the Biotype of Rice Leaffolder(Cnaphalocrocis medinalis Guenee) and Associated Resistance in Rice

郭子薇(Tzu-Wei Guo)

指導教授 ： 莊汶博

國立臺灣大學/生物資源暨農學院/農藝學研究所/碩士(2017年)

https://doi.org/10.6342/NTU201704001

摘要

水稻是世界上重要的作物之一。水稻作為地球三分之一人口的主要糧食，其栽培過程常遭受病蟲害的影響，導致產量嚴重減損。瘤野螟(Cnaphalocrocismedinalis)又稱為水稻縱捲葉蟲，藉由咬食導致水稻減產而被視為台灣近幾年水稻害蟲之一。為了要預防瘤野螟持續對水稻的危害，發展抗蟲品種成為主要的研究方向之一。然而，先前研究發現昆蟲生物小種(biotype)會影響作物抗蟲品種的抗蟲能力，也就是說不同生物小種對抗蟲品種的表現亦不同。因此我們利用兩個分子標誌：粒線體 AT-rich 和核內 internal transcribed spacer 2 來檢測瘤野螟在台灣的族群，研究結果顯示瘤野螟在台灣只有一個族群。進一步，我們利用具有抗蟲潛力的五種水稻及一種感性水稻(台中在來一號)作為研究材料，分析水稻體內防禦蛋白質，如：多酚氧化酶(PPO)、苯丙胺酸裂解酶(PAL)、過氧化酶(POD)、胰蛋白抑制劑、防禦相關基因表現、植物賀爾蒙含量以及對瘤野螟發育之影響。結果顯示抗性潛力水稻具有較高的苯丙胺酸裂解酶、過氧化酶及胰蛋白抑制劑含量，且不利瘤野螟生存，此外，抗性潛力水稻清流具有較高的水楊酸、離層酸及 JA-Ile 表現，感性品種台中在來一號則是有較高的茉莉酸表現，推測具有抗性潛力的水稻能藉由誘導高含量的 JA-Ile 來啟動下游防禦機制。

關鍵字

瘤野螟 ； 生物小種 ； 茉莉酸 ； 植物與昆蟲交互作用

並列摘要

Rice (Oryza sativa L.) is one of the most important crops in the world particularly in Asia. However, rice production and quality encounters enormous challenges, such as pests and diseases. Estimated yield losses in rice caused by pests range from 20 to 30 %. The outbreak of rice leaffolder (Cnaphalocrocis medinalis) has been recorded as an important pest of rice in Taiwan. Insect biotype, which may overcome plant resistance, has emerged as a serious problem. Thus, we used two maternally or bi-parentally inherited markers, mitochondrial AT-rich region and internal transcribed spacer 2 (ITS2) to monitor rice leaffolder population in Taiwan. The results showed that there is only one population of rice leaffolder in Taiwan. We further examined the effects of five leaffolder resistant rice varieties on insect survival. A resistant variety is defined as one that leads to a low insect survivorship. We monitored the changes of compounds known to be involved in induced plant resistance, such as defensive enzymes (PPO, PAL and POD), trypsin protease inhibitor (TPI), defensive-related genes, and phytohormone level. Our data revealed that rice variety, Qingliu, had greater response in salicylic acid (SA), abscisic acid (ABA) and jasmonyl-isoleucine (JA-Ile) compared with TN1. However, the susceptible variety TN1 had higher jasmonic acid (JA) content. It was suggested that induced JA-Ile may activate downstream defense against rice leaffolder in Qingliu. Furthermore, resistant varieties have higher levels of POD, PAL and TPI, and inducible abundance of defensive protein results in larval growth retardation.

並列關鍵字

Rice leaffolder ； biotype ； jasmonic acid ； plant-insect interaction

參考文獻

Huang S-H, Cheng C-H, Wu W-J. 2010. Possible impacts of climate change on rice insect pests and management tactics in Taiwan. Crop, Environment & Bioinformatics 7: 269-279.

廖君達, 洪巧珍. 2008. 水稻瘤野螟合成性費洛蒙田間評估. 臺中區農業改良場研究彙報 101: 45-55

Acosta-Gallegos JA, Kelly JD, Gepts P. 2007. Prebreeding in common bean and use of genetic diversity from wild germplasm. Crop Science 47: 44-59.

Apel K, Hirt H. 2004. Reactive oxygen species: metabolism, oxidative stress, and signal transduction. Annual Review of Plant Biology 55(1): 373-399.

Atkinson NJ, Lilley CJ, Urwin PE. 2013. Identification of genes involved in the response of Arabidopsis to simultaneous biotic and abiotic stresses. Plant Physiology 162(4): 2028-2041.