[Objective] The aim of this study is to investigate the chromosome pairing of F1 from Aegilops Ventricosa-Aegilops Cylindrica amphiploid × common wheat.[Method] Microsporogenesis and pollen development of Yannong...[Objective] The aim of this study is to investigate the chromosome pairing of F1 from Aegilops Ventricosa-Aegilops Cylindrica amphiploid × common wheat.[Method] Microsporogenesis and pollen development of Yannong15,SDAU18 and their hybrid F1 were observed cytologically by squash method.[Result] The results showed that microsporogenesis and pollen development of two parents including Yannong15 and SDAU18 were basically normal,and their seed setting was also basically normal.However,the microsporogenesis of their hybrid F1 was chaotic.Univalent and bivalent with high frequency of 10.11 and 18.29 per cell respectively occurred in meiotic MI（metphaseI） of PMC（pollen mother cell）.Nevertheless,only quite low frequency of multivalents occurred in meiotic PMC MI.The laggards at meiotic AI（anaphaseI） were 5 per cell on average.The number of micronucleoli in tetrad was 4.43 per cell averagely.The aborted pollen with different frequency occurred at every stage of hybrid F1 pollen development but mainly after single nucleus pollen stage.The fertile pollen rate of hybrid F1 was only 31% at 3-nucleated stage.[Conclusion] This study provides cytogenetics basis for further analysis and utilization of the amphiploid.展开更多
Studies on the reproduction and cytogenetic characterization of a primary amphidiploid Cucumis species C. hytivus Chen and Kirkbride (2n = 4x = 38) indicated that a more comprehensive cytogenetic analysis of this spec...Studies on the reproduction and cytogenetic characterization of a primary amphidiploid Cucumis species C. hytivus Chen and Kirkbride (2n = 4x = 38) indicated that a more comprehensive cytogenetic analysis of this species and its first selfed progeny would increase its potential utility in cucumber improvement. With tendrils used as source materials for mitotic analysis, chromosome numbers in all selfed progenies were 2n = 38, confirming chromosomal stability in this synthetic amphidiploid species. Detailed meiotic processes were described by comparing the primary and the selfed amphidiploids. Meiotic abnormalities, such as chromosome lagging, unequal separation, chromosome multi-polarization and polyads were observed frequently in all amphidiploid plants except for the selfed no.8, in which meiosis was arrested prior to metaphase Ⅰ. Generally, the frequency of multivalents was higher and the configurations were more complex in the selfed progenies, demonstrating a more extensive genetic exchange between cucumber and C. hystrix Chakr. Genome separation between cucumber and C. hystrix was observed through prophase Ⅰ to anaphase Ⅰ in both generations of the amphidiploids. Consequently, in addition to n = 19, a new gamete with n = 7 was produced, which was confirmed by the chromosome counts 2n = 14 in the backcrossing progenies from cucumber × amphidiploid mating. Fertility varied among the selfed amphidiploid plants. The selfed plant no.1 was found to have an improved fertility (e.g., pollen staining ability 40.8% and 25.6 seeds per fruit) and then was used as source germplasm in further introgression and gene exchange experiments.展开更多
Genetic diversity in peanut (Arachishypogaea L.) is narrow due to its evolution and domestication processes. Amphidiploids and autotetraploids (newly synthesized tetraploids) were created to broaden its genetic base. ...Genetic diversity in peanut (Arachishypogaea L.) is narrow due to its evolution and domestication processes. Amphidiploids and autotetraploids (newly synthesized tetraploids) were created to broaden its genetic base. Molecular analysis has shown that the newly synthesized tetraploids had broader genetic base;and were genetically divergent when compared to cultivated peanut. Nutritional composition relative to oil, fatty acid composition, O/L ratio, protein, iodine value and presence of plant proteinase inhibitors such as trypsin and chymotrypsin inhibitors were studied in the synthesized tetraploids. Some of the newly synthesized tetraploids had higher amounts of proteinase inhibitors. Evaluation of newly synthesized tetraploids revealed several lines resistant to late leaf spot (LLS) and peanut bud necrosis disease (PBND).展开更多
基金Supported by Doctor Scientific Research Fund from Zaozhuang University~~
文摘[Objective] The aim of this study is to investigate the chromosome pairing of F1 from Aegilops Ventricosa-Aegilops Cylindrica amphiploid × common wheat.[Method] Microsporogenesis and pollen development of Yannong15,SDAU18 and their hybrid F1 were observed cytologically by squash method.[Result] The results showed that microsporogenesis and pollen development of two parents including Yannong15 and SDAU18 were basically normal,and their seed setting was also basically normal.However,the microsporogenesis of their hybrid F1 was chaotic.Univalent and bivalent with high frequency of 10.11 and 18.29 per cell respectively occurred in meiotic MI（metphaseI） of PMC（pollen mother cell）.Nevertheless,only quite low frequency of multivalents occurred in meiotic PMC MI.The laggards at meiotic AI（anaphaseI） were 5 per cell on average.The number of micronucleoli in tetrad was 4.43 per cell averagely.The aborted pollen with different frequency occurred at every stage of hybrid F1 pollen development but mainly after single nucleus pollen stage.The fertile pollen rate of hybrid F1 was only 31% at 3-nucleated stage.[Conclusion] This study provides cytogenetics basis for further analysis and utilization of the amphiploid.
基金This research was partially supported by the Trans-century Training Program Foundation for the Talents by the State Education Commission of China to Dr.Chen Jinfeng,by the National Natural Science Founda-tion of China(301 70644 and 30470120)by National Hi-Tech R&D Program(2002AA241251 and 2004 AA241120)by Tang's Cornell-China Scholar Program and by Pickle Seed Research Foundation of PPI.
文摘Studies on the reproduction and cytogenetic characterization of a primary amphidiploid Cucumis species C. hytivus Chen and Kirkbride (2n = 4x = 38) indicated that a more comprehensive cytogenetic analysis of this species and its first selfed progeny would increase its potential utility in cucumber improvement. With tendrils used as source materials for mitotic analysis, chromosome numbers in all selfed progenies were 2n = 38, confirming chromosomal stability in this synthetic amphidiploid species. Detailed meiotic processes were described by comparing the primary and the selfed amphidiploids. Meiotic abnormalities, such as chromosome lagging, unequal separation, chromosome multi-polarization and polyads were observed frequently in all amphidiploid plants except for the selfed no.8, in which meiosis was arrested prior to metaphase Ⅰ. Generally, the frequency of multivalents was higher and the configurations were more complex in the selfed progenies, demonstrating a more extensive genetic exchange between cucumber and C. hystrix Chakr. Genome separation between cucumber and C. hystrix was observed through prophase Ⅰ to anaphase Ⅰ in both generations of the amphidiploids. Consequently, in addition to n = 19, a new gamete with n = 7 was produced, which was confirmed by the chromosome counts 2n = 14 in the backcrossing progenies from cucumber × amphidiploid mating. Fertility varied among the selfed amphidiploid plants. The selfed plant no.1 was found to have an improved fertility (e.g., pollen staining ability 40.8% and 25.6 seeds per fruit) and then was used as source germplasm in further introgression and gene exchange experiments.
文摘Genetic diversity in peanut (Arachishypogaea L.) is narrow due to its evolution and domestication processes. Amphidiploids and autotetraploids (newly synthesized tetraploids) were created to broaden its genetic base. Molecular analysis has shown that the newly synthesized tetraploids had broader genetic base;and were genetically divergent when compared to cultivated peanut. Nutritional composition relative to oil, fatty acid composition, O/L ratio, protein, iodine value and presence of plant proteinase inhibitors such as trypsin and chymotrypsin inhibitors were studied in the synthesized tetraploids. Some of the newly synthesized tetraploids had higher amounts of proteinase inhibitors. Evaluation of newly synthesized tetraploids revealed several lines resistant to late leaf spot (LLS) and peanut bud necrosis disease (PBND).
