J AcroCrop Sci J 2011 2(1):11-17 A©ademy Journals 2010 Journal of AcroCrop Science www.academyjournals.net Original Article Productivity, Grain and Dough Quality of Bread Wheat Grown with Different Water Regimes Mahmoud SELEIMAN 1* , Sayed ABDEL-AAL 2 , Mahmoud IBRAHIM 2 , Gamal ZAHRAN 3 1 Department of Agricultural Sciences, P O Box 27, FI-00014, University of Helsinki, Finland 2 Department of Crop Science, Minufiya University, Egypt 3 Agricultural Researches Center - Giza, Egypt Received: 29.11.2010 Accepted: 08.12.2010 Published: 13.12.2010 Abstract Irrigation is an important factor influencing yield and grain quality of bread wheat (Triticum aestivum L.). In the present study, we investigated the effect of different water regimes on yield components and grain quality characteristics of the bread wheat cultivar Gemmeiza 9 grown in the Nile Delta during two growing seasons. Four water regimes were compared that corresponded to three irrigations (I 3 ) and four irrigations (I 4 ) at 30 days intervals, and five irrigations (I 5 ) and six irrigations (I 6 ) at 25 days intervals. Increasing number of irrigations up to five increased yield and its components but significantly decreased bran, protein and gluten percentages and drastically changed dough characteristics assessed by both farinograph and extensograph. Water absorption and dough stability time measured by the farinograph and dough resistance to extension assessed by the extensograph significantly decreased while dough weakness and extensibility, respectively assessed by the farinograph and extensograph, increased with the number and frequency of irrigation. Flour percentage as well as bran, ash and carbohydrates concentration were significantly associated to thousand kernel weight, while gluten concentration, water absorption, dough stability time and weakness appeared to be driven by protein concentration of the grain. Different compromises between grain yield and technological and rheological qualities can be obtained by managing irrigation number and frequency. Key words: Irrigation, technological and rheological properties, Triticum aestivum L., yield * Corresponding Author: Mahmoud Seleiman, e-mail: mahmoud.seleiman@helsinki.fi, Phone:+358452652881, Fax +358 9 191 58582 INTRODUCTION Bread wheat (Triticum aestivum L.) is one of the most important crops in Egypt and the cultivated area is about 1.2 million hectares. The local production is about 8 million tons however it covers less than 60% of local consumption (FAO 2009). An important objective of the Egyptian government is consequently to reduce the dependence on imported wheat by enhancing grain yield and production (Kherallah et al. 1989). Most of the wheat in Egypt is irrigated and is grown under low rainfall and late heat stress conditions, which are representative of the wheat mega-environment 1 (ME1) as defined by Rajaram et al. (1995). In these conditions, irrigation is the major factor determining grain yield and quality. It is consequently essential to determine the water regimes leading to highest yield, maintaining an acceptable quality for bread, the main end-use product of wheat in the country. Under ME1 conditions, discrepancies were noted concerning the effects of irrigation on grain yield and quality, Alderfasi et al. (1999) and Khatun et al. (2007) showed that yield and its components can be significantly increased by increasing the number of irrigations. Bankar et al. (2008) found that the highest values of growth parameters were obtained with five irrigations (at crown root initiation, tillering, jointing, flowering and milking stages). Barber and Jessop (1987) found that increasing the number of irrigations up to three increased flour percentage but reduced grain protein and dough development time. Moroever, Dawood and Kheiralla (1994) reported that the highest values for coarse bran, flour and crude protein percentages and wet and dry gluten percentages were obtained by preventing irrigation at mid-tillering, beginning of elongation and spike-initiation