摘要:
[Objective] The effects of seedling stage,light intensity and nitrogen application rate on the content of soluble sugar and free amino acid of insect-resistant rice varieties and resistant to brown planthopper(BPH) were studied,in order to provide scientific references for insect-resistant breed and BPH control.[Method] Using the uniform design,with seedling stage,light intensity and nitrogen application rate as experimental factors,the resistance of rice varieties to BPH biotype-2 and Bangladesh biotype was identified and the content of soluble sugar and free amino acid of rice plant was measured in glass room.[Result]The resistance of different rice varieties to two BPH biotypes was decreased and even lost and died after affected by seedling stage,light intensity and nitrogen application rate.The resistance of IR56 to BPH biotype-2 and 570011 to two BPH biotypes was significantly affected by independent or interactive effects of seedling stage,light intensity and nitrogen application rate.The resistance of RP1976-18-6-4-2 to two BPH biotypes and RHT and Ptb33 to BPH Bangladesh biotype was obviously affected by independent or interactive effects of seedling stage and nitrogen application rate.Light intensity and nitrogen application rate independent effected the resistance of RHT to BPH biotype-2 and Ptb33 resistant to BPH biotype-2 obviously effected only by nitrogen application rate.The contents of soluble sugar of RHT,content of free amino acid of RP1976-18-6-4-2 and 570011 and nutrient content of IR56 and Ptb33 were significantly affected by independent or interactive effects of seedling stage,light intensity and nitrogen application rate.The contents of soluble sugar of RP1976-18-6-4-2 were obviously affected by light intensity and content of free amino acid of RHT affected by nitrogen application rate.The resistance of IR56 and 570011 to BPH biotype-2 and Bangladesh biotype and RP1976-18-6-4-2 to BPH Bangladesh biotype was closely related with the content of free amino acid and soluble sugar in rice stem.Moreover,RHT and Ptb33 resistant to two BPH biotypes and RP1976-18-6-4-2 resistant to BPH biotype-2 was closely related with the content of free amino acid in rice stem.[Conclusion] The effect of seedling stage,light intensity and nitrogen application rate on the content of soluble sugar and free amino acid in rice was obvious and the influence levels variant in different treatments and varieties.Rice plant don' t grow well and the resistance of all insect-resistant rice varieties used in this experiment was decreased and even lost and died when seedling stage too small,light intensity low and excessive nitrogen fertilizer.%[目的]研究苗龄、光照强度和施氮量对抗虫水稻品种的可溶性糖、氨基酸含量及褐飞虱抗性的影响,为抗褐飞虱的水稻品种选育及防治工作提供科学依据.[方法]开展玻璃网室试验,采用均匀设计法,以苗龄、光照强度和施氮量为试验因子,鉴定不同水稻品种对褐飞虱生物型Ⅱ和孟加拉型的抗性,测定稻株可溶性糖含量、游离氨基酸含量.[结果]受苗龄、光照强度和施氮量的影响,不同水稻品种对褐飞虱2种生物型的抗性减弱甚至丧失,乃至植株死亡.苗龄、光照强度和施氮量的单独作用或交互作用显著影响IR56对褐飞虱生物型Ⅱ的抗性及570011对2种生物型的抗性,苗龄和施氮量的单独作用及两者间交互作用显著影响RP1976-18-6-4-2对褐飞虱两种生物型的抗性及RHT和Ptb33对褐飞虱孟加拉型的抗性,光照强度和施氮量显著影响RHT对褐飞虱生物型Ⅱ的抗性,施氮量显著影响Ptb33对褐飞虱生物型Ⅱ的抗性.苗龄、光照强度和施氮量的单独作用或交互作用显著影响RHT可溶性糖含量变化、RP1976-18-6-4-2和570011游离氨基酸含量变化及IR56和Ptb33营养物质变化,光照强度显著影响RP1976-18-6-4-2可溶性糖含量变化,施氮量显著影响RHT游离氨基酸含量变化.稻茎中游离氨基酸和可溶性糖含量与IR56、570011抗褐飞虱两种生物型及RP1976-18-6-4-2抗褐飞虱孟加拉型密切相关,而游离氨基酸含量与RHT、Ptb33抗两种生物型及RP1976-18-6-4-2抗褐飞虱生物型Ⅱ密切相关.[结论]苗龄、光照强度和施氮量对水稻品种抗褐飞虱不同生物型及其可溶性糖和游离氨基酸含量的影响明显,但褐飞虱生物型不同、处理的水平不同、品种不同,其影响程度有差异.当苗龄偏弱、光照强度低、过度施氮时,会导致水稻生长不良,水稻抗虫性减弱甚至丧失,乃至稻株死亡.