A new doubled haploid (DH) rice population was established from a cross between WBPH-resistant japonica Chunjiang 06 (CJ-06) and susceptible indica TN1. Sucking inhibitory and ovicidal resistance of the DH rice lines ...A new doubled haploid (DH) rice population was established from a cross between WBPH-resistant japonica Chunjiang 06 (CJ-06) and susceptible indica TN1. Sucking inhibitory and ovicidal resistance of the DH rice lines were evaluated on the basis of non-preference response of WBPH immigrants and honeydew excretion by WBPH females, and appearance of watery lesions in the necrotic discoloration of leaf sheaths ovipositied by WBPH,respectively. Both the major gene resistance to WBPH, sucking inhibitory and ovicidal resistance, showed 1 (resistant): 1 (susceptible) segregation ratio in the DH population. Relative density of WBPH populations and damage scores in the DH population indicated combined functions of both the major resistance genes as well as QTLs affecting the host plant response to WBPH infestations. Thus, the newly developed CJ-06/TN1 DH population could be a useful material to analyze major genes and QTLs for WBPH resistance in japonica rice.展开更多
Whitebacked planthopper (WBPH) -resistance in a japonica / indica doubled haploid (DH) rice population established from a cross between WBPH-resistant japonica Chun]iang 06 and susceptible indica TN1, was comparativel...Whitebacked planthopper (WBPH) -resistance in a japonica / indica doubled haploid (DH) rice population established from a cross between WBPH-resistant japonica Chun]iang 06 and susceptible indica TN1, was comparatively evaluated through a field experiment based on the WBPH immigrant density and standardized seedbox screening test (SSST). All the susceptible DH lines in the field experiment behaved accordingly in SSST. However, 35 of resistant 66 lines (53%) in the field, were categorized to susceptible groups in SSST. Likewise, there were no significant differences in WBPH immigrant densities among 70 DH lines that were highly resistant to susceptible in SSST. The results revealed that SSST could not evaluate properly WBPH resistance in the DH lines. Four QTLs for WBPH-resistance phenotyped by the immigrant density were detected on chromosomes 2, 3, 4, and 11. Of them, the QTL on chromosome 4 was the most effective (LOD 21.8, variance 78%). Five QTLs associated with seedling mortality were mapped on chromosomes 2, 3, 4, 5 and 6. In addition to the QTL (LOD 10.5, variance 68%) on chromosome 4, there was another major QTL (LOD 12.7, variance 71%) located on chromosome 5, which was SSST-specific but might be irrespective of the WBPH resistance traits.展开更多
The vascular bundle in plants plays an important role intransportation of photosynthetic products, mineral nutri-ents, water, arid so on. Significant positive correlationswere found between grain yield, panicle traits...The vascular bundle in plants plays an important role intransportation of photosynthetic products, mineral nutri-ents, water, arid so on. Significant positive correlationswere found between grain yield, panicle traits and the No.of peduncle vascular bundles. So, it is very important tostudy the inheritance of peduncle vascular bundle, whichis a quantitative trait.展开更多
Japanese japonica rice commonlyprovides with an ovicidal resistanceagainst the whitebacked planthopper(WBPH). Similarly, ovicidal activi-ty was also found to play a significantrole in a stable field resistance toWBPH ...Japanese japonica rice commonlyprovides with an ovicidal resistanceagainst the whitebacked planthopper(WBPH). Similarly, ovicidal activi-ty was also found to play a significantrole in a stable field resistance toWBPH in some Chinese japonicarice. Rice varieties with ovicidal re-展开更多
A spontaneous rice mutant named floral organ number 3 (fon3) had major mutations in floral organ numbers. Genetic analysis indicated that fon3 acted as a single recessive gene. Microscopic observation showed that the ...A spontaneous rice mutant named floral organ number 3 (fon3) had major mutations in floral organ numbers. Genetic analysis indicated that fon3 acted as a single recessive gene. Microscopic observation showed that the number of floral organs in fon3 increased centripetally. For example, the number of pistils was the more frequently increased than organs in the outer whorls. Homeotic conversion of lodicules and glumes into palea/lemma-like organs was observed in some flowers. Scanning electron microscopy observation showed that the size of flower meristems was maintained the same or similar until the lemma primordium started to differentiate, at which time the floral meristem became enlarged, suggesting abnormal development of the inner whorls of rice florets. The relationship of fon3 with other similar rice mutants is discussed.展开更多
A spontaneous white panicle mutant was found from the F6 progenies of an indica/japonica cross. The mu-tant exhibits white stripes on its basal leaves while the pani-cles, rachis and pedicel are milky white colored at...A spontaneous white panicle mutant was found from the F6 progenies of an indica/japonica cross. The mu-tant exhibits white stripes on its basal leaves while the pani-cles, rachis and pedicel are milky white colored at flowering stage. Genetic analysis in an F2 population from the cross of Zhi7/white panicle mutant indicates that the white panicle phenotype is controlled by a single recessive nuclear gene, tentatively termed as wp(t). Using microsatellite markers, the wp(t) gene was anchored between the markers of SSR101 and SSR63.9 with a map distance of 2.3 and 0.8 cM, respec-tively, and co-segregated with the marker of SSR17 on rice chromosome 1.展开更多
Tiller angle of rice is an important agronomic trait that contributes to breed new varieties with ideal archi-tecture. In this study, we report mapping and characteriza-tion of a rice mutant defective in tiller angle....Tiller angle of rice is an important agronomic trait that contributes to breed new varieties with ideal archi-tecture. In this study, we report mapping and characteriza-tion of a rice mutant defective in tiller angle. At the seedling stage, the newly developed tillers of the mutant plants grow with a large angle that leads to a lazy phenotype at the mature stage. Genetic analysis indicates that this tiller- spreading phenotype is controlled by one recessive gene that is allelic to a reported mutant la. Therefore, the mutant was named la-2 and la renamed la-1. To map and clone LA, we constructed a large mapping population. Genetic linkage analysis showed that the LA gene is located between 2 SSR markers RM202 and RM229. By using the 6 newly-developed molecular markers, the LA gene was placed within a 0.4 cM interval on chromosome 11, allowing us to clone LA and study the mechanism that controls rice tiller angle at the molecular level.展开更多
We have analyzed a lax mutant that exhibits altered panicle architecture in rice. The primary and secondary rachis-branches are normally initiated and each branch ends in a terminal spikelet, but all the lateral spike...We have analyzed a lax mutant that exhibits altered panicle architecture in rice. The primary and secondary rachis-branches are normally initiated and each branch ends in a terminal spikelet, but all the lateral spikelets are absent and the terminal spikelet displays variegated structures in the mutant. An F2 population from the cross between the lax mutant and a japonica variety, W11, was constructed and analyzed. Using microsatellite and CAPS markers, the lax locus was mapped on the long arm of chromosome 1, co-segregated with a CAPS marker, LZ1, within an interval of 0.28 cM between a CAPS marker, HB2, and a microsatellite marker, MRG4389. RT-PCR analysis revealed that the expressions of the rice B-function MADS-box genes OsMADS2, OsMADS4, OsMADS16 and OsMADS3 were significantly reduced, whereas the expression of the rice A-function gene RAP1A was not altered.展开更多
文摘A new doubled haploid (DH) rice population was established from a cross between WBPH-resistant japonica Chunjiang 06 (CJ-06) and susceptible indica TN1. Sucking inhibitory and ovicidal resistance of the DH rice lines were evaluated on the basis of non-preference response of WBPH immigrants and honeydew excretion by WBPH females, and appearance of watery lesions in the necrotic discoloration of leaf sheaths ovipositied by WBPH,respectively. Both the major gene resistance to WBPH, sucking inhibitory and ovicidal resistance, showed 1 (resistant): 1 (susceptible) segregation ratio in the DH population. Relative density of WBPH populations and damage scores in the DH population indicated combined functions of both the major resistance genes as well as QTLs affecting the host plant response to WBPH infestations. Thus, the newly developed CJ-06/TN1 DH population could be a useful material to analyze major genes and QTLs for WBPH resistance in japonica rice.
文摘Whitebacked planthopper (WBPH) -resistance in a japonica / indica doubled haploid (DH) rice population established from a cross between WBPH-resistant japonica Chun]iang 06 and susceptible indica TN1, was comparatively evaluated through a field experiment based on the WBPH immigrant density and standardized seedbox screening test (SSST). All the susceptible DH lines in the field experiment behaved accordingly in SSST. However, 35 of resistant 66 lines (53%) in the field, were categorized to susceptible groups in SSST. Likewise, there were no significant differences in WBPH immigrant densities among 70 DH lines that were highly resistant to susceptible in SSST. The results revealed that SSST could not evaluate properly WBPH resistance in the DH lines. Four QTLs for WBPH-resistance phenotyped by the immigrant density were detected on chromosomes 2, 3, 4, and 11. Of them, the QTL on chromosome 4 was the most effective (LOD 21.8, variance 78%). Five QTLs associated with seedling mortality were mapped on chromosomes 2, 3, 4, 5 and 6. In addition to the QTL (LOD 10.5, variance 68%) on chromosome 4, there was another major QTL (LOD 12.7, variance 71%) located on chromosome 5, which was SSST-specific but might be irrespective of the WBPH resistance traits.
文摘The vascular bundle in plants plays an important role intransportation of photosynthetic products, mineral nutri-ents, water, arid so on. Significant positive correlationswere found between grain yield, panicle traits and the No.of peduncle vascular bundles. So, it is very important tostudy the inheritance of peduncle vascular bundle, whichis a quantitative trait.
文摘Japanese japonica rice commonlyprovides with an ovicidal resistanceagainst the whitebacked planthopper(WBPH). Similarly, ovicidal activi-ty was also found to play a significantrole in a stable field resistance toWBPH in some Chinese japonicarice. Rice varieties with ovicidal re-
文摘A spontaneous rice mutant named floral organ number 3 (fon3) had major mutations in floral organ numbers. Genetic analysis indicated that fon3 acted as a single recessive gene. Microscopic observation showed that the number of floral organs in fon3 increased centripetally. For example, the number of pistils was the more frequently increased than organs in the outer whorls. Homeotic conversion of lodicules and glumes into palea/lemma-like organs was observed in some flowers. Scanning electron microscopy observation showed that the size of flower meristems was maintained the same or similar until the lemma primordium started to differentiate, at which time the floral meristem became enlarged, suggesting abnormal development of the inner whorls of rice florets. The relationship of fon3 with other similar rice mutants is discussed.
文摘A spontaneous white panicle mutant was found from the F6 progenies of an indica/japonica cross. The mu-tant exhibits white stripes on its basal leaves while the pani-cles, rachis and pedicel are milky white colored at flowering stage. Genetic analysis in an F2 population from the cross of Zhi7/white panicle mutant indicates that the white panicle phenotype is controlled by a single recessive nuclear gene, tentatively termed as wp(t). Using microsatellite markers, the wp(t) gene was anchored between the markers of SSR101 and SSR63.9 with a map distance of 2.3 and 0.8 cM, respec-tively, and co-segregated with the marker of SSR17 on rice chromosome 1.
基金supposed by the State High-Tech Program(Grant No.J02-A-001)the National Natural Science Foundation of China(Grant No.30021002).
文摘Tiller angle of rice is an important agronomic trait that contributes to breed new varieties with ideal archi-tecture. In this study, we report mapping and characteriza-tion of a rice mutant defective in tiller angle. At the seedling stage, the newly developed tillers of the mutant plants grow with a large angle that leads to a lazy phenotype at the mature stage. Genetic analysis indicates that this tiller- spreading phenotype is controlled by one recessive gene that is allelic to a reported mutant la. Therefore, the mutant was named la-2 and la renamed la-1. To map and clone LA, we constructed a large mapping population. Genetic linkage analysis showed that the LA gene is located between 2 SSR markers RM202 and RM229. By using the 6 newly-developed molecular markers, the LA gene was placed within a 0.4 cM interval on chromosome 11, allowing us to clone LA and study the mechanism that controls rice tiller angle at the molecular level.
基金This work was supported by the State High Technology Research and Development Project(Grant No.2001AA21108101).
文摘We have analyzed a lax mutant that exhibits altered panicle architecture in rice. The primary and secondary rachis-branches are normally initiated and each branch ends in a terminal spikelet, but all the lateral spikelets are absent and the terminal spikelet displays variegated structures in the mutant. An F2 population from the cross between the lax mutant and a japonica variety, W11, was constructed and analyzed. Using microsatellite and CAPS markers, the lax locus was mapped on the long arm of chromosome 1, co-segregated with a CAPS marker, LZ1, within an interval of 0.28 cM between a CAPS marker, HB2, and a microsatellite marker, MRG4389. RT-PCR analysis revealed that the expressions of the rice B-function MADS-box genes OsMADS2, OsMADS4, OsMADS16 and OsMADS3 were significantly reduced, whereas the expression of the rice A-function gene RAP1A was not altered.
