In wheat (Triticumaestivum L.) the yield components are the number of spikes per unit area, the number of grains per spike and the weight per grain. From a physiological perspective the number of grains per spike is the result of the number of spikelets and the number of grains produced in each spikelet, often referred to as grain set, each of these components being determined at a different stage in crop development(W.R.SCOTT, 1977).
Although studies on yield components can be criticized on the basis that they tend to be compensatory (Adams &Grafi us 1971), such an analysis does define with more certainty the yield limiting processes in crop growth, In wheat the yield components are determined in overlapping sequence, and although there is considerable range for compensation, the amount of scope for such compensation decreases with on togeny (Rawson &Bremner 1976). The first quantitative study on flower initiation and the development of yield components of New Zeal and wheats was assumed by Langer (1965) and Langer and Khatri (1965). Broadly speaking, these studies showed that for autumn-sown wheat at Lincoln the double-ridge stage was reached in early-mid September with ear emergence taking place among late October and early November depending on cultivar. Thus the number of spikelet per spike was determined by late September and the number of grains per spikelet over the following six weeks, with most of the grain filling occurring in December and early January. Langer and Khatri (1965) also found that rapid stem elongation began in late September, presumably the time when maximum tiller numbers were present (Rawson, 1971; Jewiss 1972), but that a proportion of these tillers died during October, the survivors constituting the bulk of the final spike population.
Effect of planting methods on yield component in wheat studied by many researchers like (KILIÇ, 2015) in South-Eastern Anatolian Region, Turkey, An experiment was conducted as a randomized complete block design with four replications using a split plot treatment arrangement. The result expressed that planting methods had significant effect on yield and yield contributing characters except plant height, thousand grain weight (TGW) and protein content. Also, the mean grain yield in flat planting method was 12 % higher than bed planting method. The objective of this research was to evaluate the effects of different planting methods on grain yield and yield components of wheat.
Previous studies show that different planting methods have varying response under different experimental conditions. Hassan and Hassan (1994) have shown that wheat planted in furrows gives maximum 1000-grain weight, straw yield and grain yield. Drilling in lines and cross planting was found to be the best at Johart, Assam during studies made by Gogoi and Kalita (1995). Shaalan et al. (1977) reported that the plant density, ears m-2, number of grains per ear, 1000-grain weight and grain yield were higher in drill planted wheat than broadcasted wheat. According to silkander and Hussain et al.(2003) in Pakistan a study was conducted in 1998-99 at three sites including(kala shah kaku, Kamokey and Gujanwala),these sites were located in the rice-wheat area of punjab.planting methods included bed formation + drill sowing(BDS),broad casting +bed formation (BCB),broadcasting (BC) and drill sowing(DS),which results in plant emergence was higher in drill sowing methods on comparison with other methods .