Evaluation of early seedling, root and grain yield components of spring wheat genotypes in two sowing dates

Abstract

Background and Objective: Cultivars, time of sowing and good early seedling growth are important factors for successful wheat production. The main objective of this study was to assess the genetic variability of heat adaptive traits along with important agronomic traits, among the elite wheat lines with special focus on root traits. Materials and Methods: A set of 30 elite spring wheat genotypes were evaluated for root traits, early vigor and grain yield and its attributes at the research farm of Agriculture and Forestry University, Nepal during the wheat growing season 2015/16 under normal (4th Dec, 2015) and late (25th Dec, 2015) sowing conditions. The experiment was conducted in split-plot design with sowing date as main plot treatment and wheat genotypes as sub-plot treatment. Early vigor and root traits were assessed at Zadok’s growth stage 12 (2 leaves unfolded). Results: There were significant genotypic effects for all the studied characters. Significant differences were observed between two sowing dates for root count, root length, number of grains per spike, thousand kernel weight and grain yield. For root count and length, there was no significant genotypic difference under normal sowing, while there was highly significant genotypic difference in the late sown crop. Vijay had maximum root length in normal sowing i.e., 8.13 cm and SUP152/QUAIU #2 (35th ESWYT115) had maximum root length in late sowing i.e., 7.30 cm. The mean grain yield was 2.23 t ha-1 in normal and 1.13 t ha-1 in late sown condition. ND643/2*WBLL1//KACHU (35th ESWYT114) had maximum grain yield i.e., 3.19 t ha-1 in normal whereas Gautam had maximum grain yield (1.96 t ha-1) in late sowing. Conclusion: Significant genotypic differences for root count and root length under late sowing indicated that genotypes exhibit significant difference at seedling stage when some stress conditions are provided rather than growing under normal condition. So, selection for seedling root traits under stress conditions should be prioritized in future breeding programs for developing moisture stress tolerant wheat cultivars.