Abstract:
Possibility of
improving physiological traits and minituber yield of potato cultivars (
cvs
.
Agria and Fontane) was investigated by application of plant growth regulators (BAP,
ABA and BAP+ABA) at tuber initiation stage. Regardless of the cultivars, Net
photosynthesis ra
te (Np), actual quantum yield (Φ), stomatal conductance (g
s
) and
Transpiration rate (T
r
) of BAP
-
treated leaves were superior to those of the control. For
Agria, the greatest Chlorophyll content (Chl) was observed in BAP
-
treated plants, while
the highest Ch
l for Fontane was observed in ABA
-
treated plants. Increasing Np and Chl
content were associated with higher Soluble Carbohydrate content (SC). BAP+ABA
application increased SC of leaflets in both cultivars compared with the control. Tuber
Yield per Plant (
Y/P), Mean Tuber Weight (MTW), and Tuber Number (TN) were
stimulated by foliar treatment of plants with PGRs compared with the untreated ones,
but there were significant interactions between cultivar and hormone type. Positive
correlation between SC and Y/
P (r= 0.97*) and MTW (r= 0.97*) were observed in Agria.
Leaf area as well as dry and fresh weight of aerial parts of the BAP+ABA
-
treated plants
were more than the untreated plants and other PGR treatments. These results indicate
that either of BAP, ABA, or
their combination could be effectively used to improve
physiological traits and tuber yield of these cultivars,
although
,
Agria responded more
prominently to PGRs than Fontane.
Keywords
: Net photosynthesis rate, Photosynthetic pigments, Plant growth regul
ators,
Soluble carbohydrate, Tuberization.
