It reviewed the research and development on genetic resources in non-heading Chinese cabbage (Brassica campestris L. ssp.chinensis Makino var. communis Tsen et Lee) achieved during the past 50 years. Researches were carried out on the methodology and classification of horticultural crops, investigation and collection of the genetic resources and development of new cultivars. Further studies were conducted on the morphological and biological characteristics, identification and analysis of disease resistance and genetic model of main economic characteristics. On these bases, 13 new cultivars were selected and spread to 800,000 hm2.
It studies the changes of endogenous hormones and polyamines in cytoplasmic male sterile non-heading Chinese cabbage (Brassica campestris L. ssp. chinensis Makino var. communis Tsen et Lee). Results showed that the microspore was prone to being sterile when there were lack of IAA, GA and polyamines, especially Put and abundant with ZRs and ABA in the anther. The imbalance of IAA/ZRs also easily caused the anther sterile.
Quantitative trait loci (QTLs) identified so far in Brassica were mainly generated in the final stage of plant development, which did not apply to the exploitation of genetic effects that were expressed during a specific developmental stage. Thus, the objective of this study was to simultaneously identify unconditional and conditional QTL associated with plant height at various stages of nonheading Chinese cabbage. One hundred twelve doubled haploid (DH) lines developed from the cross between nonheading Chinese cabbage lines ‘SW-13’ and ‘SU-124’ were used for QTL analysis of plant height by the composite interval mapping method combined with mixed genetic model. The map we used for QTL analysis was an updated version of the first genetic map of nonheading Chinese cabbage with 48 additional markers to the same DH population. With data from 2 years, a total of 11 unconditional QTLs in six linkage groups and 23 conditional QTLs in eight linkage groups were identified for plant height. The results indicated that the number and type of QTLs and their genetic effects for plant height were different in a series of measuring stages. Each QTL can explain 7.92% to 28.25% of the total phenotypic variation. Two QTLs (ph8-4 and ph8-5) were identified to be associated with plant height using both unconditional and conditional mapping methods simultaneously in 2 years. These results demonstrated that it is highly effective for mapping QTL of developmental traits using the unconditional and conditional analysis methodology.