CROP & ENVIRONMENT 2011, 2(1): 24-27 ISSN :2221-0237 (PRINT) ISSN :2221-0245 (ON LINE) Please cite this article as: Anwar, J., A. Ahmad, T. Khaliq, M. Mubeen, H. M. Hammad. 2011. Optimization of sowing time for promising wheat genotypes in semiarid environment of Faisalabad. Crop Environ., 2: 24-27 Optimization of sowing time for promising wheat genotypes in semiarid environment of Faisalabad Javed Anwar 1 , Ashfaq Ahmad 2 , Tasneem Khaliq 2,* , Muhammad Mubeen 2 , S. R. Sultana 2 1 Wheat Research Institute, Ayub Agricultural Research Institutes, Faisalabad, Pakistan. 2 Agro-Climatology Lab., Department of Agronomy, University of Agriculture, Faisalabad, Pakistan. www.psa.net.pk ARTICLE INFO ABSTRACT Article history: Received 11 Nov., 2010 Accepted 30 Dec., 2010 Despite application of inputs like chemical fertilizer, pesticide and irrigation wheat cropping areas of Punjab are usually less productive due to improper selection of variety and sowing time of wheat. This study was planned to determine the proper time of sowing for promising wheat genotypes and to compare their yield behavior with already approved cultivars. Four already approved varieties of wheat i.e. Inqilab-91, Uqab-2000 , Shafaq- 2006, Seher-2006 and eight new promising lines i.e. V-03079, V-04188, V-04189, V- 03094, V-03138, V-04022, V-04112 and V-04178 were sown at six sowing dates with 10 days interval, i.e. 1-Nov, 10-Nov, 20-Nov, 30-Nov, 10-Dec, and 20-Dec. The experiment was laid out in split plot design keeping sowing dates in main plots and genotypes in sub- plots. The grain yield of most of the genotypes was highest on the sowing date 20-Nov, except genotypes V-03094 and V-04022 which gave highest yield on 10-Nov and genotypes V-03138 and V-04178 which produced highest yield on sowing date of 1-Nov. Most of the genotypes produced lesser yield at later sowing dates; however this response was different amongst genotypes. © 2011 PSA. All rights reserved Key words: Wheat cultivar Planting date Grain yield Biomass Yield components * Corresponding author: Tel.: +92-41-2409494 drtasneem@uaf.edu.pk INTRODUCTION Wheat is sown on an area of 9046 thousand hectares in Pakistan with an average yield of 2657 kg/ha (Government of Pakistan, 2010) which is very low as compared to yield potential of the approved varieties in the country. Wheat sowing is usually delayed in wheat cropping systems of Punjab, Pakistan. The delayed- sown wheat is drastically affected in terms of not only the germination, but also crop growth behavior, leaf area development, number of tillers, number of grains per spike, 1000-grain weight, test weight and eventually the grain yield. The high temperature at grain filling may be one of the yield-reducing abiotic stresses in declining yield (Rehman et al., 2007). High temperature in the post-anthesis period of late sown wheat shortens the grain filling period resulting in a smaller endosperm, lower grain weight and increased protein content. High temperature and desiccating winds during the month of April may cause forced maturity of late sown wheat, thus resulting in reduction of test weight (Singh and Dhaliwal, 2000). Early sown crops produce higher yields because they intercept more solar radiation over an extended period of growth (Ali, 1999). Delay in sowing of wheat from 20 November onward decreases grain yield @ 39 kg ha -1 day -1 (Singh and Uttam, 1994). There have been many studies which confirm the adverse effects of late sowing (Qamar et al., 2000; Singh and Pal, 2000; Subhan et al., 2004; Kumar and Sharma, 2003; Singh and Dhaliwal,2000; Chaudhary et al.,1995; Singh & Uttam,1994; Wajid et al., 2002) but on the same time sowing wheat at the first available opportunity may not always be the best economically; rather cultivars need to be matched to sowing time according to their time of flowering and maturity. In some studies, time of sowing between Nov 10 and Nov 25 did not influence the harvest index and grain yield significantly (Wajid et al., 2004; Chaudhary et al. 1995). Climate and weather conditions greatly influence the performance of new wheat cultivars both for yield and quality (Wajid et al., 2004; Sharma et al., 2006; Abdullah et al., 2007). One of the key management factors used to manage this variation is time of sowing. Varieties-sowing date interactions regarding 1000- grain weight and bread quality have been found to be highly significant showing different varietal behavior in different sowing dates (Abdullah et al., 2007; Qamar et al., 2004; Singh and Pal, 2000; Subhan et al, 2004). The aim of this study was to determine the proper time of sowing of some new wheat genotypes and to compare their yield behaviour with already approved promising cultivars in Punjab with changing sowing dates. MATERIALS AND METHODS