摘要
采用改良苗期群体筛选法,可将对褐稻虱具中抗水平的栽培稻和野生稻与感虫稻种区分开来。但如接虫量过大,则中抗稻种会被评为感虫。此外,当采用植株损害系数评价耐害性时,可用植株生长速率来代替原公式中的植株干物质比率。本法可提高工效,并且不会伤害植株,有利于抗虫品种的后代选育。
The modified seedling bulk screening test was used to evaluate the resistance to the browns planthopper in cultivated and wild rice,where five second or third-instar nymphs were used to infest each seedling at the 3.5 to 4 leaf stage.The results indicated that this screening technique could be used efficiently to identify resistance not only in the resistant rices,but also in the moderately resistant ones.But if the insect population was changed to 14 nymphs per seedling at the same leaf stage,the plants with moderate resistance would be rated as susceptible.Tolerance was evaluated as functional plant loss index (FPLI) based on plant dry weight using the formula described by Panda and Heinrichs (1983 ).On the other hand,a similar mathemetical formula based on plant growth rate used was as follows:The FPLI that was calculated on the basis of plant growth rate was demonatrated to exhibit the same trend as that based on plant dry weight.Therefore using the former parameter in determining the FPLI will save time and labor,and is not detrimental to the seedlings,since it only involves measurement of plant height.
出处
《华南农业大学学报》
CAS
CSCD
1989年第4期72-78,共7页
Journal of South China Agricultural University
关键词
水稻
抗虫性
褐稻虱
鉴定法
Nilaparvata lugens,Rice,Wild rice,Moderate resistance,Modified seedling bulk screening test
Functional plant loss index
