The genetic basis of flowering time and photoperiod sensitivity in rapeseed (Brassica napus L.)

The objective of this study was to dissect the genetic control of days to flowering (DTF) and photoperiod sensitivity (PS) into the various components including the main-effect quantitative trait loci (QTLs), epistatic QTLs and QTL-by-environment interactions (QEs). Doubled haploid (DH) fines were produced from an F1 between two spring Brassica napus cultivars Hyola 401 and Q2. DTF of the DH lines and parents were investigated in two locations, one location with a short and the other with a long photoperiod regime over two years. PS was calculated by the delay in DTF under long day as compared to that under short day. A genetic linkage map was constructed that comprised 248 marker loci including SSR, SRAP and AFLP markers. Further QTL analysis resolved the genetic components of flowering time and PS into the main-effect QTLs, epistatic QTLs and QEs. A total of 7 main-effect QTLs and 11 digenic interactions involving 21 loci located on 13 out of the 19 linkage groups were detected for the two traits. 3 main-effect QTLs and 4 pairs of epistatic QTLs were involved in QEs conferring DTF. One QTL on linkage group (LG) 18 was revealed to simultaneously affect DTF and PS and explain for the highest percentage of the phenotypic variation. The implications of the results for B. napus breeding have been discussed.

[Protective effect of purariae isoflavone on apoptosis cells of nasal mocosas in ovariectomized rats]

OBJECTIVE

To study the protective effect of purariae isoflavone on apoptosis cells of atrophic nasal mucosas in ovariectomized rats.

METHOD

60 rats were divided into four groups as control, ovariectomized, ovariectomized + nylestriol (O + N) and ovariectomized + purariae isoflavone (O + P), each with 15 rats. Earlier apotosis cells of mucosas taken from nasal septum were measured with flow cytometry.

RESULT

Compared with control group, and the number of apoptosis cells of mucosas increased after being ovariectomized,and the number of apoptosis cells of mucosas in O + N and O + D group didn't change.

CONCLUSION

Nylestriol and purariae isoflavone might have effects on protecting cells of mucosas from lacking of estrogen by decreasing apoptosis cells in ovariectomized rats.