Development Of Brown Plant Hopper Resistant Rice Restorers

Brown planthopper (Nilaparvata lugens) is one of the most serious pests for rice production. Aplication of genes with durable insect resistance to develop the rice varieties is the most economic, effective and safe method. In this way, we can simplify BPH control technologies, ruduce unnecessary economic loss, save cost of production and reduce environment pollution. At the same time, through using of advanced technologies, like MAS, we can accelerate breeding progress, shorten the breeding lifetime, and raise breeding efficiency.In this research,07WH3009, a indica rice breeding line with medium growth duration was used as a donor parent, which have Bphl4, Bphl5gene for brown planthopper resistance and CrylAb/Ac for borer resistance. Hua1176, Hua261, Huahui910and Huahui729were used as acceptor parents with excellent quality, high yield, good plant type and strong combining ability. Traditional breeding methods and molecular-marker assisted selections were used for selecting target plants in segregated offspring populations. MRG2329and MS5, as the SSR marker, were used to track the process of selection. More than100of breeding lines with BPH-resistance and acceptable phenotype were developed.The main results are as follows:1.136of F7breeding lines were developed through molecular-marker assisted selection and evaluating agronomic traits in segregated offspring populations. Of them,43lines contain both of Bph14and Bph15BPH-resistance genes,67lines with only one BPH-resistance gene of Bph15, and26lines with BPH-resistance genes and stemborer resistance gene crylAb/Ac.2. The results of BPH-resistance identifications in three years at seedling stage showed that88lines were resistant against brown planthopper (level R) and46lines were mediately resistant against brown planthopper (level MR).3. According to the results of BPH-resistance identification, heterosis identification of grain yield, phenotyping in the field trial and rice quality analysis, ZXQ10093-1and ZXQ11240were considered as two promising lines with good resistance, strong general combining ability, satisfying traits in fields and high rice quality.They may be potential using value usage in future breeding program.4.2010in Wuhan and2011in Hainan,263hybrid combinations were obtained from crossing developed BPH-resistance lines with CMS or PTGMS lines. The results of BPH-resistance identifications showed that only34combinations were mediately resistant against BPH (MR, resistance scores below5). It was implying that most of hybrid combinations ware not resistant against BPH if only male parents have BPH-resistance genes.5. The identificating results of yield hetorosis of263combinations showed that the grain yield per plant of six combinations were higher than of10%over control hybrid, Jinyou207, with similar growth duration for second crop season. And, the grain yield per plant of32combinations were higher than of10%over control hybrid, Fengliangyou1, with similar growth duration for one crop season.Guangkangl3A/ZXQ11179, Guangkangl3A/ZXQ1192、Guangkang13A/ZXQ11239and TianfengA/ZXQ11240were considered as promising combinations for one crop and Hua201S-2/ZXQ10093-1was considered as promising combinations for second crop by comprehensiving BPH resistance, yield increase and rice quality performances.