普通小麦和黑麦的双单倍体与六倍体小黑麦3种间杂交的研究

本实验用10个普通小麦和黑麦的双单倍体与5个六倍体小黑麦进行杂交。结果表明:普通小麦和黑麦的双单倍体与六倍体小黑麦杂交结实率平均为1.25%。亲本组合对3种间杂交结实率有很大的影响;F_1代植株染色体数目变化于41～49之间,大部分为2n=44～47。由于大量非整倍体的存在,F_1代各组合植株很不一致,育性降低。F_2代表现出广泛分离,并普遍存在超亲现象。在各组合中,大部分为小黑麦型,还出现中间型、普通小麦型、硬粒小麦型、分枝小黑麦型等类型。在 F_2代中,具有2n=42的植株占47.22%,育性恢复达58.88%。选择到综合性状优良的六倍体小黑麦材料。试验表明普通小麦和黑麦的双单倍体与六倍体小黑麦3种间杂交是改良六倍体小黑麦有希望的方法。

STUDY ON TRISPECIFIC HYBRIDIATION BY CROSSING AMPHIHAPLOIDS FROM COMMON WHEAT×RYE WITH HEXAPLOID TRITICALE

10 amphihaploids from common wheat×rye were crossed with 5 hexaploidtriticale cultivars.Crossability of different combinations,fertility and perfor-mance and other important characters in F_1 and F_2 were studied.Cytologicalanalysis of the meiosis of PMC of F_1 and F_2 plants was also conducted.Experimental results showed that the cross-fertility of amphihaploids fromcommon wheat×rye with hexaploid triticale averaged 1.25%.Parental com-ponents exerted significant influence on cross-fertility of such trispecific hy-bridization.Chromosome number of F_1 plants ranged 41-49 and was dominated with2n=44-47.This suggests that the maternal amphihaploids had formed gameteswith the chromosome constitution of ABDR or near to it.In F_1 generation,the presence of massive aneuploids was responsible for the extensive variationand low fertility of the F_1 plants.In F_2,drastic segregation was observed in all crosses and transgression oc-curred in all characters analysed.In every combination,most of the segregateswere triticale.Meanwhile,different numbers of intermediate type,commonwheat,durum wheat and branched triticale were produced.In F_2 populations,plants with chromosomes 2n=42 raised to 47.22%,ferti-lity restored to 58.88%.Samples of hexaploid triticale with combined desira-ble characters were selected.Trispecific hybridization by crossing amphihaploidfrom common wheat and rye with hexaplosd triticale is a prospective methodfor hexaploid triticale improvement.