| Monosomic 3, monosomic 5, monosomic 10, trisomic 4 and trisomic 5 as experiment materials, their meiosis behavior of pollen mother cell, pollen characteristics, physiological and biochemical characteristics of anther, section observation of pollen development and the structure of embryo sac were studied, and the effects on the seed set and transmission rate were analyzed. In addition, the morphology characteristics of primary trisomics system and three monosomics were observed. Conclusions were as followed:1 The loss and addition of different; chromosome had different influences over plant morphology characteristics .The monosomics were feebler than trisomics and diploids. These aneupliods can be identified according to their plants morphology characteristics.2 The diploid as female parent hybridized with aneupliods as male parent, the seed set of trisomic 4 and trisomic 5 was 14.98% and 47.12% repectively, the extra chromosome transmission rate through males was 6.98% and 11.90% repectively. The seed set and monosome transmission rate through males of monosomic 3, monosomic 5 and monosomic 10 was 0.3 There were many abnormal phenomena during meiosis. The single chromosome of monosomics behaved as a univalent during diakinesis and metaphase I, sometimes as a trivalent combining with other chromosomes which had partial homology. In addition, the single chromosome of monosomics can affect the pairing of other chromosomes, so there were three univalent. Three homologous chromosomes of trisomics associated as a trivalent or a bivalent and a univalent or three univalent during diakinesis and metaphase I. The univalent often lagged and lost or disparted into two chromosomes at anaphase I both in trisomics and monosomics ,leading to distribution of 9-9, 9-11,10-10,8-10, 9-1-9, 9-2-9, 9-1-10 besides 9-10 of monosomics and 10-10, 10-1-10, 11-11, 10-12, 10-2-10, 9-12 besides 10-11 of trisomics. There existed many separation types of monosomics and trisomics at anaphase II ,the main separation type of monosomics and trisomics was 9-9-10-10 and 10-10-11-11 respectively. The unequal separation of chromosomes reduced the transmission of monosomics and trisomics in different degree.4 The pollen activity between distinct aneupliods were different, the pollen regularity had same trend with pollen activity. The pollen activity and regularity of monosomics were lower than those of trisomics and diploids. The pollen activity and regularity of monosomic 3 were lowest. Trie decrease of pollen activity could reduce the seed set and transmission of aneupliods.5 The content of soluble sugar, starch and soluble protein of anther of monosomic 3,monosomic 5, monosomic 10 and trisomic 4 were significent lower than diploid.6 Pollen development courses of trisomic 5 were normal. The tapetum cells of monosomic 3, monosomic 5, monosomic 10 and trisomic 4 became larger and the degeneration of the tapetum cells were delayed, which lead to the abnormal development of microspore and the abortion of pollen. In addition, there were abnormal phenomena occurred during development of male gamate such as the irregularity of tetrads , the abnormality of anthers, the increase of amounts of connective vascular buddle, the bad differentiation of connective and the unification of anther chambers and so on, which have influences on the pollen abortion. The abortion of large numbers of pollen of monosomic 3, monosomic 5, monosomic 10 and trisomic 4 reduced the transmission of each monosomic and trisomic.7 The factors led to the low transmission of trisomic 5 were probably as followes: The lagging and loss of extra chromosome led to the reduction of n+1 male gamete; n+1 pollen could not germinated or formed vain pollen tube; the activities of aneuploid zygote or embryo was low.8 The abortion rate of embryo sac of monosomic 5 and monosomic 10 was 44.68% and 34.51 % respectively. They were lower significantly than those of diploid.
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