Growth and photosynthetic characteristics in pearl millet under water stress and different potassium supply

Title:

Growth and photosynthetic characteristics in pearl millet under water stress and different potassium supply

Creator:

Ashraf, M., Ahmad, Ashfaq, and McNeilly, T.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:74749667-ccb0-4f4f-9e28-c12237875445
uuid:74749667-ccb0-4f4f-9e28-c12237875445
issn:0300-3604
doi:10.1023/A:1015182310754

Subject:

drought, leaf area, net assimilation rate, net photosynthetic rate, relative growth rate, stomatal conductance, supra-optimal nutrition, transpiration rate, water potential, and water use efficiency

Type:

model:article and TEXT

Format:

bez média and svazek

Description:

Influence of supra-optimal concentrations of K on growth, water relations, and photosynthetic capacity in pearl millet under severe water deficit conditions was assessed in a glasshouse. Nineteen-days-old plants of two lines, ICMV-94133 and WCA-78, of Pennisetum glaucum (L.) R.Br. were subjected for 30 d to 235.0, 352.5, and 470.0 mg(K) kg-1(soil) and two water regimes (100 and 30 % field capacity). Increasing K supply did not alleviate the effect of water deficit on the growth of two lines of pearl millet since additional amount of K in the growth medium had no effect on shoot dry mass, relative growth rate, plant leaf area, net assimilation rate, or leaf area ratio, although there was significant effect of drought stress on these variables. Soil moisture had a significant effect on net photosynthetic rate (PN), transpiration rate, stomatal conductance, and water use efficiency of both pearl millet lines, but there was no significant effect of varying K supply on these variables. In WCA-78 an ameliorative effect of increasing supply of K on PN was observed under water deficit. Chlorophyll (Chl) a and b contents increased significantly in both lines with increase in K supply under well watered conditions, but under water deficit they increased only in ICMV-94133. Chl a/b ratios were reduced significantly in WCA-78 with increasing K supply under both watering regimes, but by contrast, in ICMV-94133 this variable was decreased only under water stress. Leaf water potential and osmotic potential of both lines decreased significantly with the imposition of drought. Leaf pressure potential in both lines increased with increase in K supply under water stress. Contents of total free amino acids in the leaves of both pearl millet lines increased significantly with increase in K supply under water stress. Potassium supply had no effect on leaf soluble sugars or soluble proteins. Considerable osmotic adjustment occurred in pearl millet plants experiencing water deficit under high K supply. and M. Ashraf, Ashfaq Ahmad, T. McNeilly.

Language:

Multiple languages

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Coverage:

389-394

Source:

Photosynthetica | 2001 Volume:39 | Number:3

Harvested from:

CDK

Metadata only:

false