Nitrogen supply after removing the shoot apex increases the nicotine concentration and nitrogen content of tobacco plants.
Ann Bot
; 96(5): 793-7, 2005 Oct.
Article
em En
| MEDLINE
| ID: mdl-16100227
ABSTRACT
BACKGROUND:
and Aims High nicotine concentrations in leaves, especially in the upper leaves, offer a serious problem for the cultivation of tobacco (Nicotiana tabacum). Preliminary field experiments showed that rapid mineralization of soil N during late stages of growth may contribute to high nicotine concentrations in leaves.METHODS:
A sand-culture experiment was carried out in the greenhouse. The N supply was controlled during the experiment, and different amounts of 15N were supplied during late stages of growth (after removal of the shoot apex), to investigate the contribution of the N taken up at this time to the N content of and nicotine concentration in tobacco plants. KEYRESULTS:
Addition of 1.6 g or 4 g 15N-labelled NH4NO3 after removing the shoot apex and flushing out the 14N did not increase leaf dry weights; however, it did result in delayed leaf senescence, more lateral bud formation, and an increase in 15N as a proportion of total N, and nicotine-15N as a proportion of total nicotine-N in each organ. The nicotine concentration, 15N and nicotine-15N abundances were increased from the bottom to the top leaves. When more 15N-labelled NH4NO3 was supplied, the nicotine concentration in leaves increased, and so did the 15N abundance in nicotine-N.CONCLUSION:
Enhanced N supply in the later growth stages (after removing the apex) increased N content and nicotine concentration in tobacco plants. Nicotine was synthesized de novo during the late growth stages.
Texto completo:
1
Coleções:
01-internacional
Temas:
Geral
Base de dados:
MEDLINE
Assunto principal:
Nicotiana
/
Brotos de Planta
/
Nicotina
/
Nitrogênio
Idioma:
En
Revista:
Ann Bot
Ano de publicação:
2005
Tipo de documento:
Article
País de afiliação:
China