普通小麦与黑麦属间杂种(F_1)育性特点的研究

34个小麦品种(系)与黑麦进行了杂交,结果表明:亲和性在供试材料间存在明显差异,其中12个小麦品种表现了与中国春相似的亲和性;对34个小麦/黑麦属间杂种(F_1)的回交结实率和开放授粉条件下的自交结实率的统计表明,杂种育性普遍较差,但不同组合间存在明显不同,其回交与自交结实率的变异幅度分别为0—4.50%和0—3.087粒/穗;小麦与黑麦属间杂种(F_1)育性与杂交亲和性间存在明显相关,回交和自交结实率以及能够回交和自交结实组合的出现频率均随亲和性的增加而表现增加的趋势;在小麦品种演化过程中,亲和性与杂种育性均表现降低的趋势;小麦/黑麦属间杂种(F_1)PMC MI染色体配对水平普遍较低,平均交叉结仅为0.359,但组合间存在一定差异,变幅为0—1.3;平均99.936%的杂种(F_1)花粉表现败育,仅有0.064%的杂种(F_1)花粉能被KI—I_2正常染色,杂种(F_1)染色体配对水平与正常染色花粉频率、正常染色花粉频率与自交结实率间存在一定程度的相关性,相关系数分别为0.209和0.205。

FERTILITY CHARACTERISTICS OF HYBRIDS(F_1)BETWEEN TRITICUM AESTIVUM L. AND SECALE CEREALE

Cross of thirty-four varieties of Triticum aestivum L. with Secale cereale revealed that crossability of 12 of the total 34 wheat varieties studied was similar to Chinese Spring. The back-cross- and self-fertility under free pollination of the 34 investigated hybrids (F1) were very poor and different, 0 - 4. 50%and 0-3.087 grains/ spike,respectively. There was significant correlation between the fertility of the hybrids and the crossability of wheat with rye. Not only the average of backcross- and self-fertility , but also the frequency of fertile hybrids (F1) showed an increasing tendency as crossability improved. The crossability and fertility of hybrids (F1) both ex- pressed a decreasing tendency during artificial evolution of wheat varieties. Chromosome pairing ability at PMC MI of the 12 observed hybrids was very low and the average of chiasmata was only 0. 359,but some changes had been detected with the range of chromosome chiasmata being 0-1.3. More than 99. 90% pollen grains from the hybrids were sterile, only 0. 064% could be normally stained by I2 - KI. Frequency of the no-mally stained pollen grains was correlated at a given level to chromosome pairing ability and self-fertility with the correlated coefficient being 0. 209 and 0. 205, respectively.