Amin Abbasi

In order to evaluate physiological parameters and grain yield of some wheat varieties under conservation agricultural condition, a split-split plot experiment based on RCBD design with three replications was conducted in Dryland Agricultural Research Institute fields during two years (2017-18 and 2018-19). Wheat-wheat and forage (vetch)-wheat rotations were located in main plots, three different crop residues (0, 2 and 4 T/ha) were arranged in sub plots and five wheat varieties (Sadra, Hashtrood, Baran, Varan, Ohadi) were considered in sub-sub plots. Results indicated that during two years chlorophyll content index, stomatal conductance and transpiration rate all of varieties were higher in forage-wheat rotation, compared to wheat-wheat treatment. Photosynthesis activity and other related traits of all varieties were improved in 2 T/ha wheat residue and in 4 T/ha forage residue. With increasing residue levels, grain weight increased as a result of grain filling duration enhancement. Varan was superior varieties in terms of grain filling duration and rate and produced maximum grain wheat. This varieties in 2 and 4 T/ha forage residue had more spikelet number per m2. Also, Varan in both rotations treatments and different levels of residues had the most grain yield than others.