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Emergence and growth dynamics of sunflower were studied at Punjab Agricultural University, Ludhiana during spring seasons of 2014 and 2015. The experiment consisted of three sowing dates (D1-January 20, D2-February 10 and D3-March 2), two intra row spacing (S1–30 cm and S2-24 cm) and four nitrogen (N) doses (N0-0, N45-45, N60-60 and N75-75 kg ha−1). Results revealed reduction in number of days taken for initiation and completion of emergence vis-a-vis emergence percentage with concomitant increase in emergence rate and vigour index due to delayed sowing. Late sown crop (D3) exhibited higher absolute growth rate (AGR), crop growth rate (CGR) and specific leaf weight (SLW) during initial phases of crop growth but early sown crop (D1) surpassed the late sown crop 50 days onward up to maturity. Early sown crop maintained higher relative growth rate (RGR) throughout the crop growth. Wider sown crop showed higher AGR, whereas CGR was higher under closer sowing. Application of N improved the AGR, CGR and RGR but SLW was improved during later growth stages (50 days onwards) only. Net assimilation rate (N AR) decreased progressively due to each delay of sowing during later growth stages. Application of N improved the NAR up to 75 DAS but between 75 DAS and maturity, application of N lowered NAR as compared to control. Correlation studies indicated significant positive correlation of seed yield with AGR, CGR and RGR between 50 and 75 DAS, emphasizing the importance of higher growth rate during grand growth period for best yield accrual in sunflower.

Afield experiment was conducted at Ludhiana during rabi season2012-13. Asetof 27 treatment combinations including three dates of sowing, viz. 16th October (D1), 15th November (D2) and 15th 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 16th October took minimum days (3) for initiation of emergence, whereas the highest number of days (8) was taken by the crop sown on 15th 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 16th October to 15th December through 15th November. At dough stage leaf area index of variety PL426 was significantly higher than other two varieties when crop sown on 16th October. It was found that the root mass density (0–15 cm) was the highest in crop sown on 15th December, which was significantly higher than crop sown on 16th October but was statistically at par with 15th 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.