The leaves of 30-d-old plants of Brassica juncea Czern & Coss cv. Varuna were sprayed with 10-6 M aqueous solutions of indole-3-yl-acetic acid (IAA), gibberellic acid (GA3), kinetin (KIN), and abscisic acid (ABA) or 10-8 M of 28-homobrassinolide (HBR). All the phytohormones, except ABA, improved the vegetative growth and seed yield at harvest, compared with those sprayed with deionised water (control). HBR was most prominent in its effect, generating 32, 30, 36, 70, 25, and 29 % higher values for dry mass, chlorophyll content, carbonic anhydrase (E.C. 4.2.1.1) activity, and net photosynthetic rate in 60-d-old plants, pods per plant, and seed yield at harvest, over the control, respectively. The order of response to various hormones was HBR > GA3 > IAA > KIN > control > ABA. and S. Hayat ... [et al.].
The interactive effect of elevated CO2 (EC) and moisture stress (MS) on Brassica juncea cv. Pusa Bold was studied using open-top chambers. The EC markedly increased net photosynthetic rate and internal CO2 concentration and reduced variable and maximal chlorophyll fluorescence. Under MS, EC increased water potential and relative water content, and reduced transpiration rate. The greater allocation of biomass to the roots, which serve as a strong sink for assimilated carbon under EC, helped in better root growth. and B. K. Rabha, D. C. Uprety.
Thirty-day-old plants of mustard (Brassica juncea L.) were sprayed with 10-10, 10-8, or 10-6 M aqueous solution of 28-homobrassinolide (HBR). The HBR-treated plants were healthier than those treated with water and yielded more. Maximum increase over control was found in 60-d-old, 10-8 M-HBR-treated plants in fresh and dry mass per plant, carbonic anhydrase (CA, E.C. 4.2.1.1) activity, and net photosynthetic rate (PN), at harvest in number of pods per plant and seed yield per plant (the respective values were 25, 30, 34, 69, 24, and 29 %). A further increase in the concentration of HBR (10-6 M) did not make any additional impact on the growth and yield. Increased CA activity and PN were correlated with growth and seed yield. and S. Hayat ... [et al.].