Reference "Are contents of Rubisco, soluble protein and nitrogen in flag leaves of rice controlled by the same genetics?"

Reference ID

7811

Title

Are contents of Rubisco, soluble protein and nitrogen in flag leaves of rice controlled by the same genetics?

Source

Journal of experimental botany, 2001, vol. 52, pp. 1827-1833

Authors (5)

Ishimaru-K	Kobayashi-N
Ono-K	Yano-M
Ohsugi-R

Abstract

Genetic relations among the contents of Rubisco, soluble protein and total leaf
nitrogen (N) in leaves of rice (Oryza sativa L.) were studied by quantitative
trait loci (QTL) analysis with a population of backcross inbred lines (BILs) of
japonica Nipponbarexindica Kasalath. The ratio of Rubisco to total leaf N in
leaves is the main target in improving photosynthetic N-use efficiency in
plants. QTLs controlling Rubisco content were not detected near QTLs for total
leaf N content. These results indicate that contents of Rubisco and total leaf N
are controlled by different genetics. QTLs that controlled the ratio of Rubisco
to total leaf N (CORNs) were detected. These results suggest that some
mechanism(s) may be involved in determining this ratio, while the contents of
Rubisco and total leaf N are controlled in other ways. In elite BILs, the ratios
of Rubisco to total leaf N were higher than those of both parents. These results
suggest a good possibility of improving N-use efficiency by CORNs in cultivated
rice. A QTL controlling Rubisco content was mapped near a QTL for soluble
protein content on chromosome 8 at 5 d after heading and on chromosome 9 at 25
d. In each chromosome region, the peaks of both QTLs overlapped accurately,
giving a high possibility of pleiotropic effects by the same genes. Different
QTLs controlling soluble protein or Rubisco were detected from those detected at
5 d or 25 d after heading. This suggests that these traits are genetically
controlled depending on the growth stages of leaves.