Influence of sowing dates and humic acid on chlorophyll and seed yield of some canola cultivars

In order to investigate the effects of different sowing dates and humic acid foliar application on seed yield, oil percentage and chlorophyll of six canola cultivars a two-year experiment was carried out in 2015 and 2016 growing seasons. The experiments were laid out in a randomized complete block design arranged in factorial split plot with three replicates. The factorial combination of three sowing dates (7th, 17th and 27th October) and two humic acid levels (0 and 2%) were allocated to the main plots and six canola cultivars (HW118, WPN6, HL3721, L14, Tassilo and Natali) were randomized in sub-plots. The results indicated that the main effects of experimental factors were significant on all studied traits. Interaction between sowing date and cultivar was also significant on all traits. In general, early seed sowing caused the highest yield and as well as oil percentage and chlorophyll. Similarly, humic acid foliar application could increase agronomic traits in canola cultivars. In sum, early seed sowing and humic acid foliar application are highly recommended in canola production.