Growth and root pattern of barley (Hordeum vulgare) varieties as influenced by date of sowing and nitrogen levels

A field experiment was conducted at Ludhiana during rabi season 2012–13. A set of 27 treatment combinations including three dates of sowing, viz. 16^th October (D₁), 15^th November (D₂) and 15^th December (D₃) in main plot, three varieties (PL 172, PL 426 and PL 807) in sub plot and three nitrogen levels, viz. 75, 100 and 125% of recommended dose of nitrogen- RDN (62.5 kg ha⁻¹) in sub-sub plot were evaluated in barley (Hordeum vulgare L.). Crop sown on 16^th October took minimum days (3) for initiation of emergence, whereas the highest number of days (8) was taken by the crop sown on 15^th December. Interaction effect of barley varieties and date of sowing on dry matter production was significant and progressive increase in dry matter production by variety PL 172 and PL 426 as the sowing was delayed from 16^th October to 15^th December through 15^th November. At dough stage leaf area index of variety PL 426 was significantly higher than other two varieties when crop sown on 16^th October. It was found that the root mass density (0–15 cm) was the highest in crop sown on 15^th December, which was significantly higher than crop sown on 16^th October but was statistically at par with 15^th November sown crop. Application of 125% of RDN crop resulted in significantly higher root density up to a depth of 15 cm than crop received 75% of RDN, but was statistically at par with crop sown with the application of 100% of RDN.