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Plant growth is often affected with hampered physiological and cellular functioning due to salinity and drought stress. To assess the effectiveness of plant bioregulators (PBRs) in mitigating abiotic stresses, a double spilt plot field study was conducted with three replications at ICAR-CSSRI, research farm, Nain, Panipat. The study comprised of three deficit irrigation regimes viz., 100, 80 and 60% of crop evapo-transpiration (ET c ) (I 1 , I 2 and I 3 ), four levels of irrigation water salinity i.e. 2, 4, 8, 12 dS m −1 (S 0 , S 1 , S 2 and S 3 ) and two PBRs salicylic acid (SA; G 1 ) and thiourea (TU; G 2 ). Irrigations, as per regimes and salinity, were applied at identified critical stages of wheat and if needed in pearl millet. PBRs were applied as seed priming and foliar sprays at two sensitive stages of respective crops. The trend of plant height, and physiological and biochemical traits was similar under different treatments at both stages, but differed significantly only at reproductive stage. Water deficit caused significant reduction in pearl millet (5.1%) and wheat (6.7%) grain yields. The reduction in grain yield under 8 and 12 dS m −1 was 12.90 and 22.43% in pearl millet and 7.68 and 32.93% in wheat, respectively compared to 2 dS m −1 . Application of either SA (G 1 ) or TU (G 2 ) significantly enhanced plant height and grain yield, but magnitude of the increment was higher with SA in pearl millet and with TU in wheat. Application of SA and TU increased grain yield by 14.42 and 12.98 in pearl millet, and 12.90 and 17.36% in wheat, respectively. The plant height, RWC, TC, MI, LP, proline, Fv/Fm and Na/K ratio significantly reduced by salinity stress in pearl millet and both water and salinity stress in wheat. Application of both PBRs proved beneficial to mitigate adverse effect of water deficit and salt stress by significantly improving physiological traits, biochemical traits and ultimately grain yield in both crops.

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Alkali lands in India occupy about 3 million ha. Due to poor physical properties, excessive exchangeable sodium and high pH, most of these lands support a very poor vegetation cover. Many of the medicinal and aromatic plants are in great demand for both internal requirements and export. But since these crops are non-conventional in nature, it is not always possible for them to be produced on fertile lands, which can be used for arable crops. The marginal lands, specifically the lands affected by salinity or sodicity problems where profitable returns are not possible from agricultural crops, could be successfully utilized for the cultivation of these high-value crops with marginal inputs. Results reported in this paper clearly indicated that out of three aromatic grasses, palmarosa (Cymbopogon martinii (Roxb.) Wats.) and lemon grass (C. flexuosus (Steud.) Wats.) could successfully be grown on moderatly alkali soils of pH up to 9Á2 while vetiver (Vetiveria zizanioides (L.) Nash), which withstands both high pH and stagnation of water, could successfully be grown without significant yield reduction on highly alkali soils. These grasses not only produce essential oils used for industrial purposes but also ameliorate the soil.

Growing salt-tolerant under-explored crops utilizing saline ground water can provide for an economic use of abandoned semiarid lands. Field trials were conducted between 1999 and 2003 on a calcareous soil in a semiarid region of northwest India. Woody perennials were planted at the sill of furrows and irrigated with water of high salinity (EC 10-28 dS m À1 ), low salinity (EC 5-9 dS m À1 ) and alternately with these two waters. Woody species included Azadirachta indica, Cordia rothii, Salvadora persica, Jatropha curcas, J. gossipifolia, Ricinus communis, Catharanthus roseus, Adhatoda vasica and Aloe barbadensis. Most of these could be grown successfully but S. persica-a highly salt-tolerant halophyte-though it produced huge biomass, could not yield mature fruit due to frost injury. The salinity build up in the soil was greater during low-rainfall years, but a good rainfall year, e.g. 714 mm in 2001, helped to leach out the accumulated salts. The uptake of Na þ in plants was greater when irrigated with water of high salinity, while K þ accumulation was greater with water of low salinity. Na þ accumulation was higher in roots as compared to other parts except in Jatropha and Salvadora, while K þ accumulation was greater in leaves. There was a negative correlation between Na þ and K þ accumulation and a positive correlation between Ca 2þ and Mg 2þ . Thus, saline water (ECiw 12 dS m À1 ) can successfully be used for growing several under-explored crops of high economic value.

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