Jj. Chen et Yj. Liao, NITROGEN-INDUCED CHANGES IN THE GROWTH AND METABOLISM OF CULTURED POTATO-TUBERS, Journal of the American Society for Horticultural Science, 118(6), 1993, pp. 831-834
The effect of N source on 'Kennebec' potato (Solanum tuberosum L.) tub
erization was investigated using single-node segments originated from
in vitro virus-free plantlets and inoculated on media with two nitrate
: ammonia ratios (low, 2:1; high, 5:1). Cell count and size and sugar
-use characteristics were measured at intervals of tuber development.
Tubers grown on high nitrate-ammonia medium exhibited higher rates of
sucrose use and higher dry-matter accumulation than tubers grown on lo
w nitrate-ammonia medium. The median value of tuber fresh weight incre
ased from 0.66 to 1.23 g as a result of increasing nitrate-ammonia. Si
gnificant differences in cell size and growth rate were observed betwe
en the two N treatments. There was also a high correlation between tub
er cell size and dry matter (p = 0.82, P less than or equal to 0.05).
These data demonstrate the importance of the nitrate : ammonium ratio
in determining C use, tuber cell size, and tuber weight. Chemical name
s used: alpha-naphtylacetic acid (NAA); 6-benzylaminopurine (BA).