Genetic behavior of Triticum aestivum–Dasypyrum villosum translocation chromosomes T6V#4S·6DL and T6V#2S·6AL carrying powdery mildew resistance

T6V#2S·6AL and T6V#4S·6DL translocation chromosomes developed from the cross of wheat and different Dasypyrum villosum accessions have good powdery mildew （PM） resistance, but their pairing and pyramiding behavior remains unclear. Results in this study indicated that the pairing frequency rate of the two differently originated 6VS chromosomes in their F1 hybrid was 18.9% according to genomic in situ hybridization （GISH）; the PM resistance plants in the F2 generation from the cross between T6V#4S·6DL translocation line Pm97033 and its PM susceptible wheat variety Wan7107 was fewer than expected. However, the ratio of the resistant vs. the susceptible plants of 15：1 in the F2 generation derived from the cross between the two translocation lines of T6V#2S·6AL and T6V#4S·6DL fitted well. Plants segregation ratio （homozygous：heterozygous：lacking） revealed by molecular marker for T6V#4S·6DL or T6V#2S·6AL in their F2 populations fitted the expected values of 1：2：1 well, inferring that the pairing of the two alien chromosome arms facilitates the transmission of T6V#4S·6DL from the F1 to the F2 generation. A quadrivalent was also observed in 21% of pollen mother cells （PMCs） of homozygote plants containing the two pairs of translocated chromosomes. The chromosome pairing between 6V#2S and 6V#4S indicates that it will be possible to obtain recombinants and clarify if the PM resistance determinant on one alien chromosome arm is different from that on the other.

两种有机锌络合物处理棉花的霉变及热解行为研究

棉花是纺织业的重要原料,是人民群众生活不可或缺的必需品,同时也是我国进出口重要的商品。研究如何安全有效地进行棉花的储备具有十分重要的现实意义。棉纤维本身含有脂肪、蜡质和果胶等适合微生物生长繁殖的营养物质。在棉花储备中,高的回潮率会加速微生物的繁殖,进而产生热量。热量的累积会引起温度升高以及棉花霉变,不利于棉花的安全有效储存。因此,通过静电吸附法将安全无毒的有机锌络合物附着在棉纤维表面,研究表明,相同条件下,处理棉的霉变状况明显得到抑制。加速发霉条件下,未处理棉的相对于白纸的平均色差值为28.10,而双乙酸锌以及苯甲酸锌防霉处理棉的色差值分别为5.16和5.86,下降了81.6%和79.1%。自然发霉条件下,双乙酸锌以及苯甲酸锌防霉处理棉的色差值分别下降了53.8%和50.7%。同时研究了纯棉以及处理棉氮气下的热分解动力学,相比于未处理棉,双乙酸锌防霉处理后活化能下降了15.8%,而苯甲酸锌防霉处理后活化能下降了10.9%。此外,利用实时红外和热重红外联用技术得到了样品在热解过程中固相以及气相的裂解产物的红外谱图,发现防霉处理能一定程度上抑制棉花热解。