关键词: 枇杷, 四倍体, 三倍体, 减数分裂, 花粉活力, 杂交, 倍性

Abstract:

The ploidy of‘B431’loquat was determined by flow cytometry and chromosome production in this study. The meiotic process of Pollen Mother Cells（PMCs）of‘B431’was observed by modified smear method，the fertility was determined by pollen germination in vitro and artificial hybridization，and the chromosome number of hybrid progenies was counted by chromosome production. The results showed that‘B431’had abnormal chromosome behavior during meiosis，such as out-of-plate chromosomes，precocious chromosomes，laggard chromosomes，chromosome bridges，micronuclei，and few triodes. The chromosome association at the diakinesis was mainly bivalents，a small quantity of univalents and patitial multivalents. There were dyads，triads，polyads and micronuclei in the tetrad. The fertility of tetraploid loquat of‘B431’was less than diploid，but with still higher fertility. There was no significant difference in fruit setting rate between‘B431’and diploid，and its pollen in vigor reached 66.29% ± 2.22%. The hybrids of‘B431’hybridized with diploid which was mainly triploid，and it reached 66.67%.‘B431’could be used to create triploid loquat.

Key words: loquat, tetraploid, triploidy, meiosis, pollen viablity, hybrid；ploidy