The feeding and oviposition behavior of the brown planthopper (BPH), Nilaparvata lugens on two transgenic indica rice homogenous genotypes (B1 and B6) with cry1Ab gene from Bacillus thuringiensis and trans...The feeding and oviposition behavior of the brown planthopper (BPH), Nilaparvata lugens on two transgenic indica rice homogenous genotypes (B1 and B6) with cry1Ab gene from Bacillus thuringiensis and transgenic restored line of hybrid rice (MSA) with SCK gene (a modified CpTI gene) were measured, compared with those on their corresponding non transgenic parental cultivars Jiazao935 and Minghui86 performed by BPH. Under the selection condition of host plants by BPH, loading percentage, oviposition preference and laying egg number of BPH both on transgenic cry1Ab rice and transgenic SCK rice were not significantly different from those on their controls, while their total number of probing wound caused by PBH expect for feeding on B1 plants was markedly more than that on the control. In contrast, under the non selection condition, total number of probing wound caused by BPH on either transgenic cry1Ab rice or transgenic SCK rice was pronouncedly more than those on their controls. Conversely, their honeydew amount excreted by BPH after feeding for 24 h was significantly less than those on the control. As a conclusion, three tested transgenic rice genotypes with insect resistance acted adverse effect on BHP feeding, and no marked effect on BPH oviposition.展开更多
Glyphosate-resistant crops have been a huge economic success for genetic engineering. The creating of new glypbosateresistant plants would increase the available choices for planting and lower the price of genetically...Glyphosate-resistant crops have been a huge economic success for genetic engineering. The creating of new glypbosateresistant plants would increase the available choices for planting and lower the price of genetically modified crop seeds. A novel G6 gene from Pseudomonas putida that encoded 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) was previously isolated. The G6 gene was transfected into rice via Agrobacterium-mediated transformation. The transgenic rice obtained was confirmed by PCR, Southern, and Western blots. The lab experiment and field trials further confirmed that the transgenic rice can survive glyphosate spraying at a dose of 8 g L^-1. In contrast, conventional rice was killed at a weed control glyphosate spray dose of 1 g L^-1. Altogether, the present study showed that the G6 gene works well in rice in vivo for glyphosate-resistance.展开更多
Transgenic Bt rice has been shown to be an effective means of controlling Lepidoptera pests of rice. However, the potential roles of transgenic rice on planthoppers and their predators need to be investigated before i...Transgenic Bt rice has been shown to be an effective means of controlling Lepidoptera pests of rice. However, the potential roles of transgenic rice on planthoppers and their predators need to be investigated before its commercialization. Population density, species dominance and population dynamics are important parameters of arthropods populations in field. So the impacts of three transgenic Bt rice strains expressing crylAb/crylAc, crylC and cry2A on population density, species dominance and population dynamics of three species of planthoppers (Nilaparvata lugens, Sogatella furcifera and Laodelphax striatellus) and their three main predators ( Cyrtorhinus lividipennis, Pirata subpiraticus and Theridium octomaculatum) were evaluated at three sites in Hubei Province, China, in the current study. The results showed that among three species of planthoppers, both in transgenic and non-transgenic rice field, the predominant species ofplanthoppers within phytophagous guild was S. furcifera at any site either growing season (46-50%). Significantly higher population density ofN. lugens was observed in T2A-1 field relative to Minghui 63 field at Wuxue in 2010. The species dominance of predator, P. subpiraticus, in TT51 field was significantly higher than that in T 1 C-19 and T2A-1 fields in 2009 at Xiaogan site. Sampling date significantly influenced six arthropods except for P. subpiraticus in 2010. The interaction between rice strain^sampling date had no significant adverse effects on the population dynamics of three species of planthoppers and their predators, except for several individual species in 2009. The interaction among rice strain^sampling date^sampling site also had no significant effect on six arthropods except for S. furcifera in 2009. The results indicated that transgenic Bt rice expressing crylAb/crylAc, cry2A and crylC had no significant adverse effects on the population dynamics of three planthoppers and their predators in most investigated data and sampling site.展开更多
Stacked(insect and herbicide resistant) transgenic rice T1c-19 with cry1C*/bar genes, its receptor rice Minghui 63(herein MH63) and a local two-line hybrid indica rice Fengliangyou Xiang 1(used as a control) we...Stacked(insect and herbicide resistant) transgenic rice T1c-19 with cry1C*/bar genes, its receptor rice Minghui 63(herein MH63) and a local two-line hybrid indica rice Fengliangyou Xiang 1(used as a control) were compared for agronomic performance under field conditions without the relevant selection pressures. Agronomic traits(plant height, tiller number, and aboveground dry biomass), reproductive ability(pollen viability, panicle length, and filled grain number of main panicles, seed set, and grain yield), and weediness characteristics(seed shattering, seed overwintering ability, and volunteer seedling recruitment) were used to assess the potential weediness without selection pressure of stacked transgene rice T1c-19. In wet direct-seeded and transplanted rice fields, T1c-19 and its receptor MH63 performed similarly regarding vegetative growth and reproductive ability, but both of them were significantly inferior to the control. T1c-19 did not display weed characteristics; it had weak overwintering ability, low seed shattering and failed to establish volunteers. Exogenous insect and herbicide resistance genes did not confer competitive advantage to transgenic rice T1c-19 grown in the field without the relevant selection pressures.展开更多
In addition to weed control in direct seeding field of hybrid rice, herbicide resistance genes were used by Chinese scientists to increase and identify the purity of hybrid seeds, and to realize the mechanization of h...In addition to weed control in direct seeding field of hybrid rice, herbicide resistance genes were used by Chinese scientists to increase and identify the purity of hybrid seeds, and to realize the mechanization of hybrid seed production. The elite restorer lines, such as Minghui 63, R752, T461, R402, D68 and E32 were transformed directly with herbicide resistance genes, in which D68 and E32 are restorer lines of two-line system and the others are of three-line system. Because almost all of important restorer lines are indica varieties and are recalcitrant in transformation, many herbicide resistant near-isogenic restorer lines were developed by sexual hybridization of indica and japonica varieties and backcross with indica restorer lines later, such as Ce 64, Minghui 63, Teqing, Milyang 46, R402 and 9311, in which 9311 is a restorer line of two-line system. The elite photoperiod-sensitive/thermo-sensitive genic male sterile lines, such as Pei'ai 64S, P88S, 4008S and 7001S, were transformed with herbicide resistance genes. A few herbicide resistant male sterile lines were developed through sexual hybridization and subsequently systemic selection, such as Bar1259S, Bar2172S, 05Z221A and 05Z227A. With the employment of herbicide resistant male sterile lines or herbicide resistant restorer lines, a few herbicide resistant hybrid rice combinations were developed, such as Xiang 125S/Bar 68-1 and Pei'ai 64S/Bar 9311. Based on herbicide resistance, the research was marching on to investigate the parental lines of hybrid rice with insect resistance, drought tolerance, etc.展开更多
Antimicrobial peptide is a polypeptide with antimicrobial activity. Antimicrobial peptide genes Np3 and Np5 from Chinese shrimp (Fenneropenaeus Chinensis) were integrated into Oryza sativa L. subsp, japonica cv. Aic...Antimicrobial peptide is a polypeptide with antimicrobial activity. Antimicrobial peptide genes Np3 and Np5 from Chinese shrimp (Fenneropenaeus Chinensis) were integrated into Oryza sativa L. subsp, japonica cv. Aichi ashahi by Agrobacterium mediated transformation system. PCR analysis showed that the positive ratios of Np3 and Np5 were 36% and 45% in To generation, respectively. RT-PCR analysis showed that the antimicrobial peptide genes were expressed in T1 generation, and there was no obvious difference in agronomic traits between transgenic plants and non-transgenic plants. Four Np3 and Np5 transgenic lines in T1 generation were inoculated with Xanthomonas oryzae pv. oryzae strain CR4, and all the four transgenic lines had significantly enhanced resistance to bacterial blight caused by the strain CR4. The Np5 transgenic lines also showed higher resistance to bacterial blight caused by strains JS97-2, Zhe 173 and OS-225. It is suggested that transgenic lines with Np5 gene might possess broad spectrum resistance to rice bacterial blight.展开更多
Maize-specific pyruvate orthophosphate dikinase(PPDK) was overexpressed in rice independently or in combination with the maize C4-specific phosphoenolpyruvate carboxylase(PCK). The wild-type(WT) cultivar Kitaake and t...Maize-specific pyruvate orthophosphate dikinase(PPDK) was overexpressed in rice independently or in combination with the maize C4-specific phosphoenolpyruvate carboxylase(PCK). The wild-type(WT) cultivar Kitaake and transgenic plants were evaluated in independent field and tank experiments. Three soil moisture treatments,well-watered(WW), moderate drought(MD) and severe drought(SD), were imposed from 9d post-anthesis till maturity. Leaf physiological and biochemical traits, root activities,biomass, grain yield, and yield components in the untransformed WT and two transgenic rice lines(PPDK and PCK) were systematically studied. Compared with the WT, both transgenic rice lines showed increased leaf photosynthetic rate: by 20%–40% under WW, by45%–60% under MD, and by 80%–120% under SD. The transgenic plants produced 16.1%,20.2% and 20.0% higher grain yields than WT under the WW, MD and SD treatments,respectively. Under the same soil moisture treatments, activities of phosphoenolpyruvate carboxylase(PEPC) and carbonic anhydrase(CA) in transgenic plants were 3–5-fold higher than those in WT plants. Compared with ribulose-1,5-bisphosphate carboxylase, activities of PEPC and CA were less reduced under both MD and SD treatments. The transgenic plants also showed higher leaf water content, stomatal conductance, transpiration efficiency, and root oxidation activity and a stronger active oxygen scavenging system than the WT under all soil moisture treatments, especially MD and SD. The results suggest that drought tolerance is greatly enhanced in transgenic rice plants overexpressing C4photosynthesis enzymes. This study was performed under natural conditions and normal planting density to evaluate yield advantages on a field basis. It may open a new avenue to droughttolerance breeding via overexpression of C4enzymes in rice.展开更多
Compared to single-trait transgenic crops, stacked transgenic plants may be more prone to become weedy, and transgene flow from stacked transgenic plants to weedy relatives may pose a potential environmental risk beca...Compared to single-trait transgenic crops, stacked transgenic plants may be more prone to become weedy, and transgene flow from stacked transgenic plants to weedy relatives may pose a potential environmental risk because these hybrids could be more advantageous under specific environmental conditions. Evaluation of the potential environmental risk caused by stacked transgenes is essential for assessing the environmental consequences caused by crop-weed transgene flow. The agronomic performance of fitness-related traits was assessed in F1+(transgene positive) hybrids(using the transgenic line T1 c-19 as the paternal parent) in monoculture and mixed planting under presence or absence glufosinate pressure in the presence or absence of natural insect pressure and then compared with the performance of F1–(transgene negative) hybrids(using the non-transgenic line Minghui 63(MH63) as the paternal parent) and their weedy rice counterparts. The results demonstrated that compared with the F1– hybrids and weedy rice counterparts, the F1+ hybrid presented higher performance(P<0.05) or non-significant changes(P>0.05) under natural insect pressure, respectively, lower performance(P<0.05) or non-significant changes(P>0.05) in the absence of insect pressure in monoculture planting, respectively. And compared to weedy rice counterparts, the F1+ hybrid presented higher performance(P<0.05) or non-significant changes(P>0.05) in the presence or absence of insect pressure in mixed planting, respectively. The F1+ hybrids presented nonsignificant changes(P>0.05) under the presence or absence glufosinate pressure under insect or non-insect pressure in monoculture planting. The all F1+ hybrids and two of three F1– hybrids had significantly lower(P<0.05) seed shattering than the weedy rice counterparts. The potential risk of gene flow from T1 c-19 to weedy rice should be prevented due to the greater fitness advantage of F1 hybrids in the majority of cases.展开更多
The 'double T-DNA' binary vector p13HSR which harbored two independent T-DNAs, containing hygromycin phosphotransferase gene (hpf) in one T-DNA region and three target genes (hLF, SB401, RZ10) in another T-DNA r...The 'double T-DNA' binary vector p13HSR which harbored two independent T-DNAs, containing hygromycin phosphotransferase gene (hpf) in one T-DNA region and three target genes (hLF, SB401, RZ10) in another T-DNA region, was used to generate selectable marker-free transgenic rice by Agrobacterium-mediated transformation. The regenerated plants with both the three target genes and the selectable marker gene hpt were selected for anther culture. RT-PCR analysis indicated that target genes were inserted in rice genomic DNA and successfully transcribed. It took only one year to obtain double haploid selectable marker-free transgenic plants containing the three target genes with co-transformation followed by anther culture technique, and the efficiency was 12.2%. It was also noted that one or two target genes derived from the binary vector were lost in some transgenic rice plants.展开更多
Phosphomannose isomerase (PMI) encoding gene manA is a desirable selective marker in transgenic research. Under- standing of its expression patterns in transgenic plant and establishing highly sensitive detection me...Phosphomannose isomerase (PMI) encoding gene manA is a desirable selective marker in transgenic research. Under- standing of its expression patterns in transgenic plant and establishing highly sensitive detection method based on immunoassay have great impacts on the application of PMI. In this study, PMI-specific monoclonal antibodies were generated using recombinant protein as immunogen, and could be used in Western blot to detect as little as 0.5 ng His-tagged PMI protein or rice expressed PMI protein in sample accounted for 0.4% of single rice grain (about 0.08 mg). PMI protein driven by CaMV-35S promoter was detected in dozens of tested tissues, including root, stem, leaf, panicle, and seed at all developmental stages during rice growing, and PMI protein accounted for about 0.036% of total protein in the leaves at seedling stage. The established method potentially can be used to monitor PMI protein in rice grains.展开更多
A synthetic cry2A^* gene enco ding Bacillus thuringiensis(Bt) δ-endotoxi n that resi st ance to lepidopteran pest was transformed into japonica rice variety Jijing 88, which is the most widely cultivated variety i...A synthetic cry2A^* gene enco ding Bacillus thuringiensis(Bt) δ-endotoxi n that resi st ance to lepidopteran pest was transformed into japonica rice variety Jijing 88, which is the most widely cultivated variety in Jilin Province, Northeast China, by Agrobacterium-mediated transformation. A total of 106 independent transformants overexpressing cry2A^* gene driven by ubiquitin(Ubi) promoter was produced. Three single-copy homozygous transgenic lines were finally selected based on the results of PCR analysis, se gregation ratio of Bast a resistance, and Southern hybridiza tion analyse s. RT-PCR and enzyme linke dimmune sorbent assay(ELISA) revealed that cry2A^* transcripts and protein were highly expressed in these lines. The high level of Cry2A^* protein expression resulted in high resistance to rice striped stem borer as evidence d by insect feeding bioassays. Our results demonst rate that cry2A^* transgenic japonica rice confers resistance to the rice striped stem borer in the laboratory conditions.展开更多
Effects of transgenic Bt rice on non-target pests following pesticide applications plays an important role in evaluating the ecological safety of transgenic rice. Changes of the life history parameters of laboratory p...Effects of transgenic Bt rice on non-target pests following pesticide applications plays an important role in evaluating the ecological safety of transgenic rice. Changes of the life history parameters of laboratory population of Nilaparvata lugens feeding on transgenic Bt rice T2A-1 and its parental line cv. MH63 as the control, and the contents of oxalic acid and soluble sugar following three pesticides (triazophos, jinggangmycin and chlorantraniliprole) treatments were investigated in this paper. Results showed that the population parameters of N. lugens and the physiological and biochemical parameters of rice did not differ significantly between T2A-1 and MH63 without pesticide application. But, the emergence rate (ER), the nymphal number of next generation (NN), and the index of population trend (IP) on T2A-1 treated with 10 mg L^-1 of triazophos were significantly higher than those on MH63, respectively, while the hatchability (HB) on T2A-1 treated with the three pesticides were obviously lower than those on MH 63. Furthermore, the content of oxalic acid in MH63 treated with 20 mg L-1 triazophos and, 40 and 80 mg L-1 chlorantraniliprole was significantly higher than that in T2A-1, while the content of soluble sugar in T2A-1 treated with 400 mg L-1 jinggangmycin was significantly higher than that in MH63. The results above indicated that triazophos in a low dose could cause a more favor of T2A-1 to population growth of N. lugens compared with MH 63.展开更多
Safety assessment of genetically modified crops generally does not take into account the potential hazard of altered patterns of heavy metal accumulation in plants. A pot experiment was conducted under greenhouse cond...Safety assessment of genetically modified crops generally does not take into account the potential hazard of altered patterns of heavy metal accumulation in plants. A pot experiment was conducted under greenhouse conditions to evaluate the impact of heavy metal amendments on the accumulation of Cd, Cu, Pb and Zn in a Bt transgenic rice Ke-Ming-Dao (KMD) and its wild-type Xiushui 11 (Xs11). In control soils, significant difference was only found in contents of Cu (p 〈 0.01) and Pb (p 〈 0.05) in straw between KMD and Xs11. At three levels of Cd amendments (5, 10, and 20 mg/kg), the Cd contents in grain and straw of KMD were significantly higher than those of Xs11, and all grain Cd contents were significantly higher than the International Criteria (0.2-0.4 mg/kg) as specified by the Codex Alimentarius Commission (CAC). These results implied that it may be unsafe for growing Bt transgenic rice in heavily Cd-polluted areas. No significant difference in Zn was found between the two varieties with the exception of roots at Zn amendment level of 600 mg/kg, while Pb contents in KMD were much higher in the straw at the lead amendment level of 1000 mg/kg and in the root at 250 mg Pb/kg. Data on the heavy metal accumulation patterns for the genetically modified rice may be used for the selection of growing areas as well as for plant residue management for Bt rice.展开更多
Aiming to controvert whether the photosynthetic capacity of transgenic rice expressing C4 genes is enhanced, with the C3-type untransformed rice (WT) and maize (a C4 plant) as controls, the activity of C4 photosyn...Aiming to controvert whether the photosynthetic capacity of transgenic rice expressing C4 genes is enhanced, with the C3-type untransformed rice (WT) and maize (a C4 plant) as controls, the activity of C4 photosynthetic enzymes, gas exchange parameters and water use efficiency (WUE) under different light intensities and temperatures, the stable carbon isotope ratio (8-3C) value and the metabolic index of active oxygen as well as plant yield parameters were determined in transgenic rice carrying the PEPC and PPDK genes (CK) in this study. The results showed that the light-saturated photosynthetic rate of CK was intermediate between that of WT and maize, with a slight bias towards that of maize. Under a high light intensity (1 200 μmol m^-2 s^-1) and high temperature (35℃), CK still exhibited higher photosynthetic capacity, while the Gs decreased. The WUE of CK was only slightly increased, and was similar to that of WT. The δ13C value indicated that CK functioned as a C3 plant. In addition, the tolerance to photo-oxidation and grain yield of CK was enhanced by sprayed with NaHSO3. In conclusion, CK possesses higher photosynthetic productivity under the conditions of high photon flux density (PFD), high temperature and spraying with NaHSO3 solution, thereby providing a new technical approach and physiological basis for constructing C4-like rice.展开更多
The determination of the environmental fate of Bt insecticidal protein released by Bt rice plants in paddy soils is a key issue in its ecological risk assessment. In this study, the impacts of soil water content, pH, ...The determination of the environmental fate of Bt insecticidal protein released by Bt rice plants in paddy soils is a key issue in its ecological risk assessment. In this study, the impacts of soil water content, pH, and temperature on the degradation of CrylAb protein expressed in the leaves of Bt rice KMD2 were studied in the laboratory. Three types of paddy soils were used, i.e., blue clayey paddy soil, pale paddy soil on quaternary red soil, and marine-fluvigenic yellow loamy paddy soil. Ground powders of KMD2 leaf blades were mixed with each type of soil, and degradation dynamics of Cry lAb were measured using enzyme-linked immunosorbent assay (ELISA). The degradation rate of CrylAb was high at the early experimental stage, but slowed down steadily at middle and later stages, which could be described by exponential equations, with the half-life period of degradation determined as 1.8-4.0 d. The soil water content, pH, and temperature could affect the degradation of CrylAb, but the effects of soil pH and temperature were relatively greater. In general, CrylAb degradations were slower under lower soil pH and temperature conditions, especially for marine-fluvigenic yellow loamy paddy soil.展开更多
The transgenic rice KMD1, expressing a synthetic CrylAb gene from Bacillus thuringiensis, showed effective resistance to the older (third-to fifth-instar) larvae of the rice leaf-folder (RLF), Cnaphalocrocis medin...The transgenic rice KMD1, expressing a synthetic CrylAb gene from Bacillus thuringiensis, showed effective resistance to the older (third-to fifth-instar) larvae of the rice leaf-folder (RLF), Cnaphalocrocis medinalis (Guenee) in laboratory bioassay. Significant declines were revealed in food consumption and growth of the older RLF nymphs fed on the cut-leaves of transgenic KMD1 plants. The increase rate of food consumption by larvae fed on KMD1 was drastically lower than those on Xiushui 11. Food consumption was varied with different instars when the larvae fed on the Bt rice. Those of fourth- and fifth-instar larvae were different compared to the third-instar, lower than those on the non-transgenic rice but still increased a little when the feeding time prolonged. It is indicated that younger RLF larvae are more sensitive to Bt rice than older ones. Also, about 81%, 78% and 68% of the third-, fourth- and fifth-instar RLF larvae died within 72 hours bioassay period on KMD1 leaves, respectively. These results demonstrated that Bt-transgene in KMD1 rice confers substantial protection against infestations with older RLF larvae.展开更多
The safety of feeding transgenic crylAb/crylAc rice (a genetically modified (GM) rice variety) to broilers was examined from an immunological perspective. HatchlingArborAcres chickens (240) were assigned to two ...The safety of feeding transgenic crylAb/crylAc rice (a genetically modified (GM) rice variety) to broilers was examined from an immunological perspective. HatchlingArborAcres chickens (240) were assigned to two dietary treatments (diets containing GM or non-GM rice) with 12 replicates per group and 10 birds per replicate. Traits were measured on one randomly selected bird from each replicate at d 21 and 42. The 42-d feeding trial revealed that crylAb/crylAc rice had no significant effect relative to non-GM rice on body weight and the immune organ indices. No significant pathological lesion in the spleen and bursa of Fabricius was found in the GM rice group. There were no significant differences in serum concentrations of immunoglobulin Y (IgY), IgM, interleukin 4 (IL-4) and IL-6 between the two groups at d 21 or 42, except for IL-6 being higher (P〈0.05) in the GM- fed chickens at d 42. There were no differences in the T and B lymphocyte transformation rate and CD4+/CD8+ ratio between the two groups at d 42. Additionally, there was no significant difference between the two diets in expression of relevant genes viz. the major histocompatibility complex class II beta chain (BLB2), interferon beta 1 (IFNβ), tumour necrosis factor alpha-like (TNFa) and toll-like receptor 4 (TLR4)in the spleen and bursa of Fabricius. All the data demonstrated that transgenic crylAb/ crylAc rice had no adverse effect on these aspects of immune function of broilers during 42-d feeding trial. Transgenic rice was therefore indistinguishable from non-GM rice in terms of short-term feeding in chickens.展开更多
The amylose content(AC)of rice endosperm starch varies from 0 to 35%,and is associated with rice cooking and eating quality.Soft rice has low AC,generally between 6%and 15%,and its eating quality is high whether it is...The amylose content(AC)of rice endosperm starch varies from 0 to 35%,and is associated with rice cooking and eating quality.Soft rice has low AC,generally between 6%and 15%,and its eating quality is high whether it is consumed hot or cold.However,the appearance quality of current soft rice cultivars needs to be improved,especially opaque endosperm.Conventional genetic engineering has improved some agronomic traits of soft rice varieties,but not endosperm appearance.In the present study,a RNAi construct of the soluble starch synthase II-2(SSSII-2)and the hygromycin phosphotransferase(HPT)gene were introduced into an elite japonica rice variety,Kangtiaowuyunjing(KWY8)by co-transformation.Several selectable marker-free(SMF)transgenic lines were obtained,and SSSII-2 expression was significantly downregulated in selected transgenic lines,resulting in lower AC of the endosperm.The physicochemical properties of the transgenic rice kernels,including gel consistency(GC)and rapid visco analyzer(RVA)profile,differed significantly from those of wild-type rice and were similar to those of a soft rice variety,Nanjing 46(NJ46).These findings indicate that the cooking,eating,and processing qualities of transgenic rice are comparable to those of NJ46.However,the transgenic rice endosperm retained a transparent appearance under low-moisture conditions.Thus,SMF SSSII-2 RNAi rice provides a resource for breeding soft rice with transparent endosperm.展开更多
The transgenic rice, Zhongda 2, which was genetically modified from an indica rice line Zhuxian B by rice chitinase gene (RC24), had high resistance to rice sheath blight (Rhizoctonia solan!) in laboratory and a two-y...The transgenic rice, Zhongda 2, which was genetically modified from an indica rice line Zhuxian B by rice chitinase gene (RC24), had high resistance to rice sheath blight (Rhizoctonia solan!) in laboratory and a two-year field experiment. The pathogen could invade sheath of Zhongda 2 and induce symptoms of the disease. No difference was noted in time of penetration or incubation period between Zhongda 2 and non-transgenic rice control, Zhuxian B, but the hyphae lysate could be observed earlier than control. Its resistance expressed as to inhibit the growth of mycelium in host tissue. Fis from Zhongda 2(4) crossed with other five non-transgenic rice lines showed higher resistance than donor non-transgenic parents, but the resistance was different along with the different maternal parents.展开更多
文摘The feeding and oviposition behavior of the brown planthopper (BPH), Nilaparvata lugens on two transgenic indica rice homogenous genotypes (B1 and B6) with cry1Ab gene from Bacillus thuringiensis and transgenic restored line of hybrid rice (MSA) with SCK gene (a modified CpTI gene) were measured, compared with those on their corresponding non transgenic parental cultivars Jiazao935 and Minghui86 performed by BPH. Under the selection condition of host plants by BPH, loading percentage, oviposition preference and laying egg number of BPH both on transgenic cry1Ab rice and transgenic SCK rice were not significantly different from those on their controls, while their total number of probing wound caused by PBH expect for feeding on B1 plants was markedly more than that on the control. In contrast, under the non selection condition, total number of probing wound caused by BPH on either transgenic cry1Ab rice or transgenic SCK rice was pronouncedly more than those on their controls. Conversely, their honeydew amount excreted by BPH after feeding for 24 h was significantly less than those on the control. As a conclusion, three tested transgenic rice genotypes with insect resistance acted adverse effect on BHP feeding, and no marked effect on BPH oviposition.
文摘Glyphosate-resistant crops have been a huge economic success for genetic engineering. The creating of new glypbosateresistant plants would increase the available choices for planting and lower the price of genetically modified crop seeds. A novel G6 gene from Pseudomonas putida that encoded 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) was previously isolated. The G6 gene was transfected into rice via Agrobacterium-mediated transformation. The transgenic rice obtained was confirmed by PCR, Southern, and Western blots. The lab experiment and field trials further confirmed that the transgenic rice can survive glyphosate spraying at a dose of 8 g L^-1. In contrast, conventional rice was killed at a weed control glyphosate spray dose of 1 g L^-1. Altogether, the present study showed that the G6 gene works well in rice in vivo for glyphosate-resistance.
基金supported by the National Genetically Modified Organisms Breeding Major Project:Technology of Environmental Risk Assessment on Transgenic Rice (2008ZX08011-001)Technology of Environment Risk Assessment of Transgenic Rice on Rice Planthopper Population (2009ZX08011-009B)
文摘Transgenic Bt rice has been shown to be an effective means of controlling Lepidoptera pests of rice. However, the potential roles of transgenic rice on planthoppers and their predators need to be investigated before its commercialization. Population density, species dominance and population dynamics are important parameters of arthropods populations in field. So the impacts of three transgenic Bt rice strains expressing crylAb/crylAc, crylC and cry2A on population density, species dominance and population dynamics of three species of planthoppers (Nilaparvata lugens, Sogatella furcifera and Laodelphax striatellus) and their three main predators ( Cyrtorhinus lividipennis, Pirata subpiraticus and Theridium octomaculatum) were evaluated at three sites in Hubei Province, China, in the current study. The results showed that among three species of planthoppers, both in transgenic and non-transgenic rice field, the predominant species ofplanthoppers within phytophagous guild was S. furcifera at any site either growing season (46-50%). Significantly higher population density ofN. lugens was observed in T2A-1 field relative to Minghui 63 field at Wuxue in 2010. The species dominance of predator, P. subpiraticus, in TT51 field was significantly higher than that in T 1 C-19 and T2A-1 fields in 2009 at Xiaogan site. Sampling date significantly influenced six arthropods except for P. subpiraticus in 2010. The interaction between rice strain^sampling date had no significant adverse effects on the population dynamics of three species of planthoppers and their predators, except for several individual species in 2009. The interaction among rice strain^sampling date^sampling site also had no significant effect on six arthropods except for S. furcifera in 2009. The results indicated that transgenic Bt rice expressing crylAb/crylAc, cry2A and crylC had no significant adverse effects on the population dynamics of three planthoppers and their predators in most investigated data and sampling site.
基金supported by the China Transgenic Organism Research and Commercialization Project (2016ZX08011-001)the National Natural Science Fund Project (31270579)+1 种基金the Specialized Research Fund for the Doctoral Program of Higher Education, China (20130097130006)the 111 Project of China (B07030)
文摘Stacked(insect and herbicide resistant) transgenic rice T1c-19 with cry1C*/bar genes, its receptor rice Minghui 63(herein MH63) and a local two-line hybrid indica rice Fengliangyou Xiang 1(used as a control) were compared for agronomic performance under field conditions without the relevant selection pressures. Agronomic traits(plant height, tiller number, and aboveground dry biomass), reproductive ability(pollen viability, panicle length, and filled grain number of main panicles, seed set, and grain yield), and weediness characteristics(seed shattering, seed overwintering ability, and volunteer seedling recruitment) were used to assess the potential weediness without selection pressure of stacked transgene rice T1c-19. In wet direct-seeded and transplanted rice fields, T1c-19 and its receptor MH63 performed similarly regarding vegetative growth and reproductive ability, but both of them were significantly inferior to the control. T1c-19 did not display weed characteristics; it had weak overwintering ability, low seed shattering and failed to establish volunteers. Exogenous insect and herbicide resistance genes did not confer competitive advantage to transgenic rice T1c-19 grown in the field without the relevant selection pressures.
文摘In addition to weed control in direct seeding field of hybrid rice, herbicide resistance genes were used by Chinese scientists to increase and identify the purity of hybrid seeds, and to realize the mechanization of hybrid seed production. The elite restorer lines, such as Minghui 63, R752, T461, R402, D68 and E32 were transformed directly with herbicide resistance genes, in which D68 and E32 are restorer lines of two-line system and the others are of three-line system. Because almost all of important restorer lines are indica varieties and are recalcitrant in transformation, many herbicide resistant near-isogenic restorer lines were developed by sexual hybridization of indica and japonica varieties and backcross with indica restorer lines later, such as Ce 64, Minghui 63, Teqing, Milyang 46, R402 and 9311, in which 9311 is a restorer line of two-line system. The elite photoperiod-sensitive/thermo-sensitive genic male sterile lines, such as Pei'ai 64S, P88S, 4008S and 7001S, were transformed with herbicide resistance genes. A few herbicide resistant male sterile lines were developed through sexual hybridization and subsequently systemic selection, such as Bar1259S, Bar2172S, 05Z221A and 05Z227A. With the employment of herbicide resistant male sterile lines or herbicide resistant restorer lines, a few herbicide resistant hybrid rice combinations were developed, such as Xiang 125S/Bar 68-1 and Pei'ai 64S/Bar 9311. Based on herbicide resistance, the research was marching on to investigate the parental lines of hybrid rice with insect resistance, drought tolerance, etc.
基金supported by the Important National Science & Technology Specific Projects for Breeding New Transgenic Varieties in China (Grant No. 2008ZX08010-004)
文摘Antimicrobial peptide is a polypeptide with antimicrobial activity. Antimicrobial peptide genes Np3 and Np5 from Chinese shrimp (Fenneropenaeus Chinensis) were integrated into Oryza sativa L. subsp, japonica cv. Aichi ashahi by Agrobacterium mediated transformation system. PCR analysis showed that the positive ratios of Np3 and Np5 were 36% and 45% in To generation, respectively. RT-PCR analysis showed that the antimicrobial peptide genes were expressed in T1 generation, and there was no obvious difference in agronomic traits between transgenic plants and non-transgenic plants. Four Np3 and Np5 transgenic lines in T1 generation were inoculated with Xanthomonas oryzae pv. oryzae strain CR4, and all the four transgenic lines had significantly enhanced resistance to bacterial blight caused by the strain CR4. The Np5 transgenic lines also showed higher resistance to bacterial blight caused by strains JS97-2, Zhe 173 and OS-225. It is suggested that transgenic lines with Np5 gene might possess broad spectrum resistance to rice bacterial blight.
基金the National Basic Research Program (973 Program, 2012CB114306)the National Natural Science Foundation of China (31061140457+6 种基金 31071360 31271641)the National Key Technology Support Program of China (2011BAD16B14 2012BAD04B08)China National Public Welfare Industry (Agriculture) Plan (200803030 201203079)Jiangsu Advantages of Key Construction Projects (JS 2011)
文摘Maize-specific pyruvate orthophosphate dikinase(PPDK) was overexpressed in rice independently or in combination with the maize C4-specific phosphoenolpyruvate carboxylase(PCK). The wild-type(WT) cultivar Kitaake and transgenic plants were evaluated in independent field and tank experiments. Three soil moisture treatments,well-watered(WW), moderate drought(MD) and severe drought(SD), were imposed from 9d post-anthesis till maturity. Leaf physiological and biochemical traits, root activities,biomass, grain yield, and yield components in the untransformed WT and two transgenic rice lines(PPDK and PCK) were systematically studied. Compared with the WT, both transgenic rice lines showed increased leaf photosynthetic rate: by 20%–40% under WW, by45%–60% under MD, and by 80%–120% under SD. The transgenic plants produced 16.1%,20.2% and 20.0% higher grain yields than WT under the WW, MD and SD treatments,respectively. Under the same soil moisture treatments, activities of phosphoenolpyruvate carboxylase(PEPC) and carbonic anhydrase(CA) in transgenic plants were 3–5-fold higher than those in WT plants. Compared with ribulose-1,5-bisphosphate carboxylase, activities of PEPC and CA were less reduced under both MD and SD treatments. The transgenic plants also showed higher leaf water content, stomatal conductance, transpiration efficiency, and root oxidation activity and a stronger active oxygen scavenging system than the WT under all soil moisture treatments, especially MD and SD. The results suggest that drought tolerance is greatly enhanced in transgenic rice plants overexpressing C4photosynthesis enzymes. This study was performed under natural conditions and normal planting density to evaluate yield advantages on a field basis. It may open a new avenue to droughttolerance breeding via overexpression of C4enzymes in rice.
基金financially supported by the China Transgenic Organism Research and Commercialization Project (2016ZX08011-001)
文摘Compared to single-trait transgenic crops, stacked transgenic plants may be more prone to become weedy, and transgene flow from stacked transgenic plants to weedy relatives may pose a potential environmental risk because these hybrids could be more advantageous under specific environmental conditions. Evaluation of the potential environmental risk caused by stacked transgenes is essential for assessing the environmental consequences caused by crop-weed transgene flow. The agronomic performance of fitness-related traits was assessed in F1+(transgene positive) hybrids(using the transgenic line T1 c-19 as the paternal parent) in monoculture and mixed planting under presence or absence glufosinate pressure in the presence or absence of natural insect pressure and then compared with the performance of F1–(transgene negative) hybrids(using the non-transgenic line Minghui 63(MH63) as the paternal parent) and their weedy rice counterparts. The results demonstrated that compared with the F1– hybrids and weedy rice counterparts, the F1+ hybrid presented higher performance(P<0.05) or non-significant changes(P>0.05) under natural insect pressure, respectively, lower performance(P<0.05) or non-significant changes(P>0.05) in the absence of insect pressure in monoculture planting, respectively. And compared to weedy rice counterparts, the F1+ hybrid presented higher performance(P<0.05) or non-significant changes(P>0.05) in the presence or absence of insect pressure in mixed planting, respectively. The F1+ hybrids presented nonsignificant changes(P>0.05) under the presence or absence glufosinate pressure under insect or non-insect pressure in monoculture planting. The all F1+ hybrids and two of three F1– hybrids had significantly lower(P<0.05) seed shattering than the weedy rice counterparts. The potential risk of gene flow from T1 c-19 to weedy rice should be prevented due to the greater fitness advantage of F1 hybrids in the majority of cases.
文摘The 'double T-DNA' binary vector p13HSR which harbored two independent T-DNAs, containing hygromycin phosphotransferase gene (hpf) in one T-DNA region and three target genes (hLF, SB401, RZ10) in another T-DNA region, was used to generate selectable marker-free transgenic rice by Agrobacterium-mediated transformation. The regenerated plants with both the three target genes and the selectable marker gene hpt were selected for anther culture. RT-PCR analysis indicated that target genes were inserted in rice genomic DNA and successfully transcribed. It took only one year to obtain double haploid selectable marker-free transgenic plants containing the three target genes with co-transformation followed by anther culture technique, and the efficiency was 12.2%. It was also noted that one or two target genes derived from the binary vector were lost in some transgenic rice plants.
基金supported in part by the Natural Science Foundation of Beijing, China (5121001)the Cultivate New Varieties of Genetically Modified Organisms Technology Major Projects, the Ministry of Science and Technology of China (2009ZX08012-006B)
文摘Phosphomannose isomerase (PMI) encoding gene manA is a desirable selective marker in transgenic research. Under- standing of its expression patterns in transgenic plant and establishing highly sensitive detection method based on immunoassay have great impacts on the application of PMI. In this study, PMI-specific monoclonal antibodies were generated using recombinant protein as immunogen, and could be used in Western blot to detect as little as 0.5 ng His-tagged PMI protein or rice expressed PMI protein in sample accounted for 0.4% of single rice grain (about 0.08 mg). PMI protein driven by CaMV-35S promoter was detected in dozens of tested tissues, including root, stem, leaf, panicle, and seed at all developmental stages during rice growing, and PMI protein accounted for about 0.036% of total protein in the leaves at seedling stage. The established method potentially can be used to monitor PMI protein in rice grains.
基金funded by the National Major Project for Transgenic Organism Breeding, China (201408001001-009)
文摘A synthetic cry2A^* gene enco ding Bacillus thuringiensis(Bt) δ-endotoxi n that resi st ance to lepidopteran pest was transformed into japonica rice variety Jijing 88, which is the most widely cultivated variety in Jilin Province, Northeast China, by Agrobacterium-mediated transformation. A total of 106 independent transformants overexpressing cry2A^* gene driven by ubiquitin(Ubi) promoter was produced. Three single-copy homozygous transgenic lines were finally selected based on the results of PCR analysis, se gregation ratio of Bast a resistance, and Southern hybridiza tion analyse s. RT-PCR and enzyme linke dimmune sorbent assay(ELISA) revealed that cry2A^* transcripts and protein were highly expressed in these lines. The high level of Cry2A^* protein expression resulted in high resistance to rice striped stem borer as evidence d by insect feeding bioassays. Our results demonst rate that cry2A^* transgenic japonica rice confers resistance to the rice striped stem borer in the laboratory conditions.
基金funded by the National Science and Technology Major Project of the Ministry of Science and Technology of China (2009ZX08011-009B)the Scientific Innovation Research of College Graduate in Jiangsu Province, China (CXZZ11-0986)
文摘Effects of transgenic Bt rice on non-target pests following pesticide applications plays an important role in evaluating the ecological safety of transgenic rice. Changes of the life history parameters of laboratory population of Nilaparvata lugens feeding on transgenic Bt rice T2A-1 and its parental line cv. MH63 as the control, and the contents of oxalic acid and soluble sugar following three pesticides (triazophos, jinggangmycin and chlorantraniliprole) treatments were investigated in this paper. Results showed that the population parameters of N. lugens and the physiological and biochemical parameters of rice did not differ significantly between T2A-1 and MH63 without pesticide application. But, the emergence rate (ER), the nymphal number of next generation (NN), and the index of population trend (IP) on T2A-1 treated with 10 mg L^-1 of triazophos were significantly higher than those on MH63, respectively, while the hatchability (HB) on T2A-1 treated with the three pesticides were obviously lower than those on MH 63. Furthermore, the content of oxalic acid in MH63 treated with 20 mg L-1 triazophos and, 40 and 80 mg L-1 chlorantraniliprole was significantly higher than that in T2A-1, while the content of soluble sugar in T2A-1 treated with 400 mg L-1 jinggangmycin was significantly higher than that in MH63. The results above indicated that triazophos in a low dose could cause a more favor of T2A-1 to population growth of N. lugens compared with MH 63.
基金supported by the National Transgenic Major Program (No. 2009ZX08011-014B)the Chinese Postdoctoral Science Foundation (No. 20080431318)the Science and Technology Department of Zhejiang Province
文摘Safety assessment of genetically modified crops generally does not take into account the potential hazard of altered patterns of heavy metal accumulation in plants. A pot experiment was conducted under greenhouse conditions to evaluate the impact of heavy metal amendments on the accumulation of Cd, Cu, Pb and Zn in a Bt transgenic rice Ke-Ming-Dao (KMD) and its wild-type Xiushui 11 (Xs11). In control soils, significant difference was only found in contents of Cu (p 〈 0.01) and Pb (p 〈 0.05) in straw between KMD and Xs11. At three levels of Cd amendments (5, 10, and 20 mg/kg), the Cd contents in grain and straw of KMD were significantly higher than those of Xs11, and all grain Cd contents were significantly higher than the International Criteria (0.2-0.4 mg/kg) as specified by the Codex Alimentarius Commission (CAC). These results implied that it may be unsafe for growing Bt transgenic rice in heavily Cd-polluted areas. No significant difference in Zn was found between the two varieties with the exception of roots at Zn amendment level of 600 mg/kg, while Pb contents in KMD were much higher in the straw at the lead amendment level of 1000 mg/kg and in the root at 250 mg Pb/kg. Data on the heavy metal accumulation patterns for the genetically modified rice may be used for the selection of growing areas as well as for plant residue management for Bt rice.
基金supported in part by the State Key Basic Research and Development Plan of China (973Program,G1998010100)the College Natural Science Foundation of Jiangsu Province of China (08KJD180012)the Key Subject Ecology of Nanjing Xiaozhuang University of China (2005NXY01)
文摘Aiming to controvert whether the photosynthetic capacity of transgenic rice expressing C4 genes is enhanced, with the C3-type untransformed rice (WT) and maize (a C4 plant) as controls, the activity of C4 photosynthetic enzymes, gas exchange parameters and water use efficiency (WUE) under different light intensities and temperatures, the stable carbon isotope ratio (8-3C) value and the metabolic index of active oxygen as well as plant yield parameters were determined in transgenic rice carrying the PEPC and PPDK genes (CK) in this study. The results showed that the light-saturated photosynthetic rate of CK was intermediate between that of WT and maize, with a slight bias towards that of maize. Under a high light intensity (1 200 μmol m^-2 s^-1) and high temperature (35℃), CK still exhibited higher photosynthetic capacity, while the Gs decreased. The WUE of CK was only slightly increased, and was similar to that of WT. The δ13C value indicated that CK functioned as a C3 plant. In addition, the tolerance to photo-oxidation and grain yield of CK was enhanced by sprayed with NaHSO3. In conclusion, CK possesses higher photosynthetic productivity under the conditions of high photon flux density (PFD), high temperature and spraying with NaHSO3 solution, thereby providing a new technical approach and physiological basis for constructing C4-like rice.
基金This study was financially supported by the National Natural Science Foundation of China (30070500) to Cheng Jiaan.
文摘The determination of the environmental fate of Bt insecticidal protein released by Bt rice plants in paddy soils is a key issue in its ecological risk assessment. In this study, the impacts of soil water content, pH, and temperature on the degradation of CrylAb protein expressed in the leaves of Bt rice KMD2 were studied in the laboratory. Three types of paddy soils were used, i.e., blue clayey paddy soil, pale paddy soil on quaternary red soil, and marine-fluvigenic yellow loamy paddy soil. Ground powders of KMD2 leaf blades were mixed with each type of soil, and degradation dynamics of Cry lAb were measured using enzyme-linked immunosorbent assay (ELISA). The degradation rate of CrylAb was high at the early experimental stage, but slowed down steadily at middle and later stages, which could be described by exponential equations, with the half-life period of degradation determined as 1.8-4.0 d. The soil water content, pH, and temperature could affect the degradation of CrylAb, but the effects of soil pH and temperature were relatively greater. In general, CrylAb degradations were slower under lower soil pH and temperature conditions, especially for marine-fluvigenic yellow loamy paddy soil.
基金the National Basic Research Program(001CB109004)from the Ministry of Science and Technology of China.
文摘The transgenic rice KMD1, expressing a synthetic CrylAb gene from Bacillus thuringiensis, showed effective resistance to the older (third-to fifth-instar) larvae of the rice leaf-folder (RLF), Cnaphalocrocis medinalis (Guenee) in laboratory bioassay. Significant declines were revealed in food consumption and growth of the older RLF nymphs fed on the cut-leaves of transgenic KMD1 plants. The increase rate of food consumption by larvae fed on KMD1 was drastically lower than those on Xiushui 11. Food consumption was varied with different instars when the larvae fed on the Bt rice. Those of fourth- and fifth-instar larvae were different compared to the third-instar, lower than those on the non-transgenic rice but still increased a little when the feeding time prolonged. It is indicated that younger RLF larvae are more sensitive to Bt rice than older ones. Also, about 81%, 78% and 68% of the third-, fourth- and fifth-instar RLF larvae died within 72 hours bioassay period on KMD1 leaves, respectively. These results demonstrated that Bt-transgene in KMD1 rice confers substantial protection against infestations with older RLF larvae.
基金supported by the grants from the National Science and Technology Major Project of the Ministry of Science and Technology of China (2012ZX08011001005)the Agricultural Science and Technology Innovation Program, China (ASTIP-IAS04)the Earmarked Fund for Modern Agro-Industry Technology Research System, China (CARS-42)
文摘The safety of feeding transgenic crylAb/crylAc rice (a genetically modified (GM) rice variety) to broilers was examined from an immunological perspective. HatchlingArborAcres chickens (240) were assigned to two dietary treatments (diets containing GM or non-GM rice) with 12 replicates per group and 10 birds per replicate. Traits were measured on one randomly selected bird from each replicate at d 21 and 42. The 42-d feeding trial revealed that crylAb/crylAc rice had no significant effect relative to non-GM rice on body weight and the immune organ indices. No significant pathological lesion in the spleen and bursa of Fabricius was found in the GM rice group. There were no significant differences in serum concentrations of immunoglobulin Y (IgY), IgM, interleukin 4 (IL-4) and IL-6 between the two groups at d 21 or 42, except for IL-6 being higher (P〈0.05) in the GM- fed chickens at d 42. There were no differences in the T and B lymphocyte transformation rate and CD4+/CD8+ ratio between the two groups at d 42. Additionally, there was no significant difference between the two diets in expression of relevant genes viz. the major histocompatibility complex class II beta chain (BLB2), interferon beta 1 (IFNβ), tumour necrosis factor alpha-like (TNFa) and toll-like receptor 4 (TLR4)in the spleen and bursa of Fabricius. All the data demonstrated that transgenic crylAb/ crylAc rice had no adverse effect on these aspects of immune function of broilers during 42-d feeding trial. Transgenic rice was therefore indistinguishable from non-GM rice in terms of short-term feeding in chickens.
基金supported by the Key Transgenic Breeding Program of China(2016ZX08001006,2016ZX08001002-003)the National Key Research and Development Program(2016YFD0102000)+3 种基金Yangzhou City Science and Technology Plan(YZ2017059)the National Natural Science Foundation of China(31872859)Jiangsu Agricultural Science and Technology Innovation Fund(CX181001)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘The amylose content(AC)of rice endosperm starch varies from 0 to 35%,and is associated with rice cooking and eating quality.Soft rice has low AC,generally between 6%and 15%,and its eating quality is high whether it is consumed hot or cold.However,the appearance quality of current soft rice cultivars needs to be improved,especially opaque endosperm.Conventional genetic engineering has improved some agronomic traits of soft rice varieties,but not endosperm appearance.In the present study,a RNAi construct of the soluble starch synthase II-2(SSSII-2)and the hygromycin phosphotransferase(HPT)gene were introduced into an elite japonica rice variety,Kangtiaowuyunjing(KWY8)by co-transformation.Several selectable marker-free(SMF)transgenic lines were obtained,and SSSII-2 expression was significantly downregulated in selected transgenic lines,resulting in lower AC of the endosperm.The physicochemical properties of the transgenic rice kernels,including gel consistency(GC)and rapid visco analyzer(RVA)profile,differed significantly from those of wild-type rice and were similar to those of a soft rice variety,Nanjing 46(NJ46).These findings indicate that the cooking,eating,and processing qualities of transgenic rice are comparable to those of NJ46.However,the transgenic rice endosperm retained a transparent appearance under low-moisture conditions.Thus,SMF SSSII-2 RNAi rice provides a resource for breeding soft rice with transparent endosperm.
基金supported by the Program for Supporting New-century Excellent Talents of Ministry of Education, China (Grant No. NCET-04-0907)the Program for Supporting Development of Innovative Research Teams of Ministry of Education, China (Grant No. IRT0453)the Applied Basic Research Program of Sichuan Province, China (Grant No. 2008JY0023-1)
文摘The transgenic rice, Zhongda 2, which was genetically modified from an indica rice line Zhuxian B by rice chitinase gene (RC24), had high resistance to rice sheath blight (Rhizoctonia solan!) in laboratory and a two-year field experiment. The pathogen could invade sheath of Zhongda 2 and induce symptoms of the disease. No difference was noted in time of penetration or incubation period between Zhongda 2 and non-transgenic rice control, Zhuxian B, but the hyphae lysate could be observed earlier than control. Its resistance expressed as to inhibit the growth of mycelium in host tissue. Fis from Zhongda 2(4) crossed with other five non-transgenic rice lines showed higher resistance than donor non-transgenic parents, but the resistance was different along with the different maternal parents.