Effect of light on growth rate, development and yield of spring rapeseed

Spring rapeseed is one of the most important oilseed crops worldwide. Currently, one rapeseed development cycle takes about five to six months. Shortening the growing season can significantly reduce the growing period and speed up the realization of breeding and research projects. This could allow up to four generations of rapeseed instead of two or three under greenhouse conditions. Our research was conducted in 2023–2024 in a two-section climatic chamber developed at Federal Scientific Agroengineering Center VIM. The aim of the study was to study the effect of accelerating the growing season of rape by increasing the photoperiod and using different spectral composition of light. The experiment was conducted in 4 variants: Variant 1 (22/2 RB) — photoperiod 22 h day / 2 h night and spectral composition R:40/B:60 (red-blue spectrum only); Variant 2 (22/2 FS) — photoperiod 22 h day / 2 h night and full spectrum FS (UV0.5: B37: G6.5: Y3: R49: FR4); Variant 3 (16/8 RB) — photoperiod 16 h / 8 h night and spectral composition R:40/B:60 (red-blue spectrum only); Variant 4 (16/8 FS) (control) — photoperiod 16 h day / 8 h night and full spectrum (UV0.5: B37: G6.5: Y3: R49: FR4). We achieved a reduction in growing season by 14 days using an extended photoperiod (22-hour daylight hours) and full spectrum radiation (UV0.5: B37: G6.5: Y3: R49: FR4). It was found that variants 1 and 2 used in the experiment could be used to obtain rape seeds of proper quality. The best was variant 2–22/2 FS using 22 hour daylight hours and full spectrum radiation (UV0.5: B37: G6.5: Y3: R49: FR4).