In order to clarify the relationships between seedling and adult-plant resis- tance to English grain aphid Sitobion avenae （Fabricius）, 94 wheat cultivars were screened and evaluated based on aphid number ratio thro...In order to clarify the relationships between seedling and adult-plant resis- tance to English grain aphid Sitobion avenae （Fabricius）, 94 wheat cultivars were screened and evaluated based on aphid number ratio through artificial inoculation in greenhouse and natural infection in field from 2010 to 2012. The results indicated that 43 wheat cultivars were resistant to aphid at different levels, of which two dis- played high resistance, eight moderate resistance and 33 low resistance at adult- plant stage. Meanwhile, 45 wheat cultivars exhibited aphid resistance at seedling stage, including 5 highly-resistant cultivars, 16 moderately-resistant cultivars and 24 low-resistant cultivars. Thirty wheat cultivars showed resistance to aphids to different degrees at both seedling and adult-plant stages, accounting for 31.91% of all tested wheat cultivars, especially that C273 and Lanmai （Shaanxi Zhashui） showed high aphid resistance. Aphid number ratio of wheat cultivars at seedling stage had an extremely significant positive correlation with that at adult-plant stage. Additionally, 66 wheat cultivars exhibited the same resistance to aphids at both seedling and adult-plant stages, accounting for 70.21% of all cultivars. The study demonstrated that inoculation test at seedling stage in greenhouse is a reliable method for identi- fying wheat resistance to S. avenae.展开更多
In order to characterize the genetic relationship of the geographic populations of Sitobion avenae （Hemiptera： Aphididae） in China, a 588 bp region of the mitochondrial cytochrome oxidase subunit I （mtDNA-COI） ge...In order to characterize the genetic relationship of the geographic populations of Sitobion avenae （Hemiptera： Aphididae） in China, a 588 bp region of the mitochondrial cytochrome oxidase subunit I （mtDNA-COI） gene was sequenced and analyzed among the different geographic populations. 269 individuals were collected from 17 localities in different wheat-growing areas in China that covered most of the range reported for this species. Within the sequence among these geographic populations, 15 polymorphic sites defined 16 distinct haplotypes, ranging in sequence divergence from 0.2% （one nucleotide） to 1.7% （10 nucleotides）. Of the 15 variable sites, 12 were transitional substitutions, 2 were transversional substitutions and 1 was transitional and transversional substitution. Phylogenetic analysis showed that all haplotypes were highly interconnected with each other, in absence of phylogeographic structing. Each of 8 haplotypes was found only at one locality, and the other haplotypes were the widespread distributed in the different localities. The higher genetic diversity was found in the northern China populations than that in the southern China populations. The low genetic differentiation （FST=-0.06945-0.69857） and high migration rate （Nm=0.21575-infinite） of Chinese populations suggest that dispersal over long distance is a major factor in the demography of S. avenae.展开更多
This article was to study the potential resistance mechanism of three different wheat varieties （Ww2730, Xiaoyan 22 and Batis） in the seedling stage to Sitobion avenae. The aphid feeding behavior was ascertained by ...This article was to study the potential resistance mechanism of three different wheat varieties （Ww2730, Xiaoyan 22 and Batis） in the seedling stage to Sitobion avenae. The aphid feeding behavior was ascertained by stylet penetration activities monitoring using the electrical penetration graph （EPG） technique. When the aphids feed on Ww2730 seedlings, the time for the 1st duration probing was later than that on Xiaoyan 22 and Batis significantly, and the number of interrupted probing before the 1st duration probing was more than that on Xiaoyan 22 and Batis significantly, and the 1st duration probing was shorter than that on Xiaoyan 22 and Batis significantly. The durations of the stylet pierce from the extra- to the intra-cellular （pd Ⅱ-1） on Ww2730 and Xiaoyan 22 were longer than those on Batis significantly. The duration of the potential drop （pd） in C wave on Ww2730 was longer than that on Xiaoyan 22 and Batis significantly. The times and duration of the G wave （ingestion in xylem） on Ww2730 were more and longer than those on Xiaoyan 22 and Batis significantly. The times of spot G wave on Batis was more than that on Ww2730 significantly, but the duration of spot G was shorter than that on Xiaoyan 22 and Ww2730 significantly. The total time of E1 wave, the longest duration of E1 fractions, and the mean duration time of E1 fractions that followed E2 wave on Xiaoyan 22 and Batis were all significantly longer than those on Ww2730. There was no difference of the mean duration of the 1st E1 wave on the 3 varieties, but the mean durations of other E1 wave on Ww2730 and Xiaoyan 22 were shorter than those on Batis significantly. The other wave parameters, including times and durations of F and E2 were all not different on the 3 wheat varieties. It is suggested that the resistance mechanism of wheat variety Ww2730 to S. avenae is a restriction factor of feeding in epidermis, the thicker cell wall in mesophyll, and secondary metabolites or nutrition unbalance in phloem in the seedling phase. The resistance mechanism of Xiaoyan 22 is thicker cell wall and more cell layer in mesophyll in the seedling phase. The feeding strategy of S. avenae against the resistance of Ww2730 was to shorten the second duration of secrete watery salivation to xylem than the first.展开更多
Sitobion avenae(F.) and Rhopalosiphum padi(L.) are two important pests of wheat in China.They typically coexist in fields during the late period of wheat growth.Sulfoxaflor is a novel sulfoximine insecticide that demo...Sitobion avenae(F.) and Rhopalosiphum padi(L.) are two important pests of wheat in China.They typically coexist in fields during the late period of wheat growth.Sulfoxaflor is a novel sulfoximine insecticide that demonstrates broad-spectrum efficacy,especially in targeting sap-feeding insects.This study was carried out to investigate the sublethal effects of sulfoxaflor on the development,longevity,and reproduction of two species of wheat aphids.Our results showed that sublethal concentrations of sulfoxaflor did not cause significant effects on the fecundity or the longevity of the parent generation(F0 generation) of either S.avenae or R.padi.However,it caused transgenerational sublethal effects.For S.avenae,adult longevity of F1 generation was significantly decreased.No significant differences were observed on the population parameters of S.avenae in the F1 generation.For R.padi,the adult preoviposition period(APOP) and the total preoviposition period(TPOP) of F1 generation were significantly reduced.The mean generation time(T) was significantly reduced in the R.padi F1 generation.What’s more,the intrinsic rate of increase(rm) and the finite rate of increase(λ) were significantly increased in the R.padi F1 generation.Taken together,these results suggest that exposure to the LC25 of sulfoxafl had no effects on the parent generation of S.avenae or R.padi,but it reduced adult longevity of S.avenae as a negative effect and increased the rm and λ of R.padi in the first progeny generation,which may have an impact on the population dynamics of R.padi.展开更多
基金Supported by the Exploration and Innovation and Utilization of Wheat Germplasm Resource(2013BAD01B02-6)the National Natural Science Foundation of China(30900897)the Cyrus Tang Foundation of America~~
文摘In order to clarify the relationships between seedling and adult-plant resis- tance to English grain aphid Sitobion avenae （Fabricius）, 94 wheat cultivars were screened and evaluated based on aphid number ratio through artificial inoculation in greenhouse and natural infection in field from 2010 to 2012. The results indicated that 43 wheat cultivars were resistant to aphid at different levels, of which two dis- played high resistance, eight moderate resistance and 33 low resistance at adult- plant stage. Meanwhile, 45 wheat cultivars exhibited aphid resistance at seedling stage, including 5 highly-resistant cultivars, 16 moderately-resistant cultivars and 24 low-resistant cultivars. Thirty wheat cultivars showed resistance to aphids to different degrees at both seedling and adult-plant stages, accounting for 31.91% of all tested wheat cultivars, especially that C273 and Lanmai （Shaanxi Zhashui） showed high aphid resistance. Aphid number ratio of wheat cultivars at seedling stage had an extremely significant positive correlation with that at adult-plant stage. Additionally, 66 wheat cultivars exhibited the same resistance to aphids at both seedling and adult-plant stages, accounting for 70.21% of all cultivars. The study demonstrated that inoculation test at seedling stage in greenhouse is a reliable method for identi- fying wheat resistance to S. avenae.
基金supported by the National Basic Research Program of China (973 Program, 2006CB102004)the National S&T Major Project of China (2009ZX08012-007B)+1 种基金the National Natural Science Foundation of China (30971920)the Inter-University Targeted Project between Belgium and China (PIC SHANDONG)
文摘In order to characterize the genetic relationship of the geographic populations of Sitobion avenae （Hemiptera： Aphididae） in China, a 588 bp region of the mitochondrial cytochrome oxidase subunit I （mtDNA-COI） gene was sequenced and analyzed among the different geographic populations. 269 individuals were collected from 17 localities in different wheat-growing areas in China that covered most of the range reported for this species. Within the sequence among these geographic populations, 15 polymorphic sites defined 16 distinct haplotypes, ranging in sequence divergence from 0.2% （one nucleotide） to 1.7% （10 nucleotides）. Of the 15 variable sites, 12 were transitional substitutions, 2 were transversional substitutions and 1 was transitional and transversional substitution. Phylogenetic analysis showed that all haplotypes were highly interconnected with each other, in absence of phylogeographic structing. Each of 8 haplotypes was found only at one locality, and the other haplotypes were the widespread distributed in the different localities. The higher genetic diversity was found in the northern China populations than that in the southern China populations. The low genetic differentiation （FST=-0.06945-0.69857） and high migration rate （Nm=0.21575-infinite） of Chinese populations suggest that dispersal over long distance is a major factor in the demography of S. avenae.
基金This study was supported financially by the Cooperation Project Foundation between the Ministries of Agriculture of Germany and China(02/03)National Natural Science Foundation of China(39970112)Youth Foundation of Northwest A&F University(080807,08080252).
文摘This article was to study the potential resistance mechanism of three different wheat varieties （Ww2730, Xiaoyan 22 and Batis） in the seedling stage to Sitobion avenae. The aphid feeding behavior was ascertained by stylet penetration activities monitoring using the electrical penetration graph （EPG） technique. When the aphids feed on Ww2730 seedlings, the time for the 1st duration probing was later than that on Xiaoyan 22 and Batis significantly, and the number of interrupted probing before the 1st duration probing was more than that on Xiaoyan 22 and Batis significantly, and the 1st duration probing was shorter than that on Xiaoyan 22 and Batis significantly. The durations of the stylet pierce from the extra- to the intra-cellular （pd Ⅱ-1） on Ww2730 and Xiaoyan 22 were longer than those on Batis significantly. The duration of the potential drop （pd） in C wave on Ww2730 was longer than that on Xiaoyan 22 and Batis significantly. The times and duration of the G wave （ingestion in xylem） on Ww2730 were more and longer than those on Xiaoyan 22 and Batis significantly. The times of spot G wave on Batis was more than that on Ww2730 significantly, but the duration of spot G was shorter than that on Xiaoyan 22 and Ww2730 significantly. The total time of E1 wave, the longest duration of E1 fractions, and the mean duration time of E1 fractions that followed E2 wave on Xiaoyan 22 and Batis were all significantly longer than those on Ww2730. There was no difference of the mean duration of the 1st E1 wave on the 3 varieties, but the mean durations of other E1 wave on Ww2730 and Xiaoyan 22 were shorter than those on Batis significantly. The other wave parameters, including times and durations of F and E2 were all not different on the 3 wheat varieties. It is suggested that the resistance mechanism of wheat variety Ww2730 to S. avenae is a restriction factor of feeding in epidermis, the thicker cell wall in mesophyll, and secondary metabolites or nutrition unbalance in phloem in the seedling phase. The resistance mechanism of Xiaoyan 22 is thicker cell wall and more cell layer in mesophyll in the seedling phase. The feeding strategy of S. avenae against the resistance of Ww2730 was to shorten the second duration of secrete watery salivation to xylem than the first.
基金supported by the National Barley Industry Technology System of China(CARS-05)
文摘Sitobion avenae(F.) and Rhopalosiphum padi(L.) are two important pests of wheat in China.They typically coexist in fields during the late period of wheat growth.Sulfoxaflor is a novel sulfoximine insecticide that demonstrates broad-spectrum efficacy,especially in targeting sap-feeding insects.This study was carried out to investigate the sublethal effects of sulfoxaflor on the development,longevity,and reproduction of two species of wheat aphids.Our results showed that sublethal concentrations of sulfoxaflor did not cause significant effects on the fecundity or the longevity of the parent generation(F0 generation) of either S.avenae or R.padi.However,it caused transgenerational sublethal effects.For S.avenae,adult longevity of F1 generation was significantly decreased.No significant differences were observed on the population parameters of S.avenae in the F1 generation.For R.padi,the adult preoviposition period(APOP) and the total preoviposition period(TPOP) of F1 generation were significantly reduced.The mean generation time(T) was significantly reduced in the R.padi F1 generation.What’s more,the intrinsic rate of increase(rm) and the finite rate of increase(λ) were significantly increased in the R.padi F1 generation.Taken together,these results suggest that exposure to the LC25 of sulfoxafl had no effects on the parent generation of S.avenae or R.padi,but it reduced adult longevity of S.avenae as a negative effect and increased the rm and λ of R.padi in the first progeny generation,which may have an impact on the population dynamics of R.padi.
