caa a22 4500 47579382X CHVBK 20180406123718.0 cr unu---uuuuu 170329e20000801xx s 000 0 eng 10.1007/s001220051493 doi (NATIONALLICENCE)springer-10.1007/s001220051493 Mapping the jp (jumbo pollen) gene and QTLs involved in multinucleate microspore formation in diploid alfalfa [Elektronische Daten] [S. Tavoletti, P. Pesaresi, G. Barcaccia, E. Albertini, F. Veronesi] Abstract : The objective of this research was to map the jumbo-pollen trait in diploid alfalfa. Homozygous recessive (jpjp) plants are characterized by the complete failure of post-meiotic cytokinesis during microsporogenesis resulting in 100% 4n-pollen formation. Three F1 segregating populations were produced and analyzed for pollen-grain production and the segregation of RFLP markers. The first cross combination did not segregate for the jumbo-pollen trait, but showed a clear segregation for multinucleate (bi-, tri- and tetra-nucleate)-microspore formation. Cytological analysis showed that few plants produced 100% normal (uninucleate) microspores, whereas most of them produced multinucleate microspores at a variable frequency (0-75%). Plants with multinucleate microspores always showed a prevalence of binucleated microspores, even though some plants showed a background presence of tri- and tetra-nucleate microspores. QTL analysis based on ANOVA I and Stepwise Multiple Regression identified three QTLs with a highly significant effect on multinucleate-microspore formation. Two cross combinations, subsequently executed, showed Mendelian segregation for the jumbo-pollen trait and were effective in locating the jp gene on linkage group 6 close to the Vg1G1b RFLP locus. Interestingly, this RFLP locus was also linked to one QTL for multinucleate-microspore formation. Genetic models are discussed concerning the presence in linkage group 6 of a cluster of genes involved in multinucleate-microspore formation together with possible relationships between the jp gene and the Vg1G1b QTL. Springer-Verlag Berlin Heidelberg, 2000 Keywords Alfalfa nationallicence Post-meiotic cytokinesis nationallicence RFLP nationallicence 4n pollen nationallicence Tavoletti S. Dipartimento di Biotecnologie Agrarie ed Ambientali, Università degli Studi di Ancona, Via Brecce Bianche, 60131 Ancona, Italy, IT aut Pesaresi P. Dipartimento di Biotecnologie Agrarie ed Ambientali, Università degli Studi di Ancona, Via Brecce Bianche, 60131 Ancona, Italy, IT aut Barcaccia G. Dipartimento di Agronomia Ambientale e Produzioni Vegetali, Università degli Studi di Padova, Agripolis, Via Romea, 35020 Padova, Italy, IT aut Albertini E. Istituto di Miglioramento Genetico Vegetale, Università degli Studi di Ancona, Borgo XX Giugno, 06121 Perugia, Italy, IT aut Veronesi F. Istituto di Miglioramento Genetico Vegetale, Università degli Studi di Ancona, Borgo XX Giugno, 06121 Perugia, Italy, IT aut https://doi.org/10.1007/s001220051493 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s001220051493 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Tavoletti S. Dipartimento di Biotecnologie Agrarie ed Ambientali, Università degli Studi di Ancona, Via Brecce Bianche, 60131 Ancona, Italy, IT aut NATIONALLICENCE 700 1- Pesaresi P. Dipartimento di Biotecnologie Agrarie ed Ambientali, Università degli Studi di Ancona, Via Brecce Bianche, 60131 Ancona, Italy, IT aut NATIONALLICENCE 700 1- Barcaccia G. Dipartimento di Agronomia Ambientale e Produzioni Vegetali, Università degli Studi di Padova, Agripolis, Via Romea, 35020 Padova, Italy, IT aut NATIONALLICENCE 700 1- Albertini E. Istituto di Miglioramento Genetico Vegetale, Università degli Studi di Ancona, Borgo XX Giugno, 06121 Perugia, Italy, IT aut NATIONALLICENCE 700 1- Veronesi F. Istituto di Miglioramento Genetico Vegetale, Università degli Studi di Ancona, Borgo XX Giugno, 06121 Perugia, Italy, IT aut Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer