Effect of Seed Bio-Priming with Selected Strains of Trichoderma harzianum and Pseudomonas fluorescens on Wheat Crop in Field and under Pot Conditions under Water Deficient Conditions

Importance of wheat (Triticum aestivum L.) as staple food is well known as nearly 35% of the world population depends on wheat and demand for wheat is expected to grow faster than any other major crop. It provides about 20 percent of the total food calories for the human being. Wheat is grown primarily for the grain which is ground and utilized in the form of flour called atta or whole-meal for the manufacturing various kinds of breads, cakes, cookies, crackers, breakfast, cereals etc. Drought is one of the most common environmental stresses that affect growth and development of plants. Drought continues to be important challenge to agricultural scientists. It is assumed that by the year 2025, around 1.8 billion people will face absolute water shortage and 65% of the world’s population will live under water-stressed environments (Nezhadahmadi et al., 2013). It is also certain that increased crop yield will be required to meet the food needs of future population growth; water deficit causes will be a major constraints for crop yield in rain fed and irrigated area (Ray et al., 2015). Drought or water deficit is major environmental stress threatening wheat productivity world wide. Global climate models predict changed precipitation pattern with frequent episodes of drought. Although drought impedes wheat performance at all growth stages, it is more critical during the flowering and grains- filling phases (terminal drought) and result in substantial yield losses. The severity and duration of stress determine the extent of yield loss. Trichoderma releases a variety of compounds that induce resistance responses against biotic and abiotic stresses (Harman et al., 2006). Incorporation of Trichoderma through seed bio-priming in many cereals and vegetable crops has resulted in increased levels of plant growth harmones and improved seed performance (Howell, 2013).