Role of Ca2+ on growth of Brassica campestris L. and B. juncea (L.) Czern & Coss under Na+ stress.
Root and shoot growth of Brassica campestris L. and B. juncea increased significantly (P < 0.01) with enhanced Ca(2+) treatment along with 60 mM NaCl in the root medium. The maximum fresh mass of shoot and root in B. juncea was recorded at 10 mM Ca(2+) concentration. The relative growth rate of shoot of both species reached its maximum at 8 mM of Ca(2+) concentration. Average rate of Ca(2+) intake (I(Ca)) was higher in B. juncea than B. campestris. In B. juncea, the average transport of Ca(2+) to shoot increased by 19%, 38%, 119%, 125% and 169% compared with the control. Furthermore specific utilization rate of Ca(2+) was higher in B. juncea than B. campestris. In B. campestris it increased by 9%, 32%, 41% and 59% at 4, 6, 8, and 10 mM of calcium in comparison to 2 mM Ca(2+) treatment. At 4, 6, 8 and 10 mM of Ca(2+) application, the increase in the leaf area ratio was 10, 17, 23 and 30%, respectively. In the shoot and root portions of B. campestris and B. juncea, Ca(2+) had a linear relationship with potassium and sulfur, whereas it was in antagonism with sodium ion.
Badr-uz-Zaman
Land Resources Research Programme, Institute of Natural Resources and Environmental Sciences, National Agricultural Research Centre, Islamabad 45500, Pakistan. badruaar@yahoo.com
Salim
M
M
Asghar
Rehana
R
D001937:Brassica / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism* / Q000494:pharmacology; D018515:Plant Leaves / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D018520:Plant Shoots / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D012964:Sodium / Q000494:pharmacology*
D012964:Sodium; D002118:Calcium