Sunflower planting: how about sunflower deficiency?

What happens when sunflowers lack nutrients? Please describe in detail the following symptoms of sunflower nutrient deficiency for reference: nitrogen deficiency Seedling growth is not fast, thin plants, leaves small and thin, yellow-green or light green; mid-growth nitrogen deficiency, lower leaves early yellow, small flower disk, significantly poor growth of vegetative organs, resulting in premature aging of plants. potassium deficiency The plant grows slowly, leaves turn yellow, brown spots appear on the leaves, these spots finally dry into thin pieces broken off, oil content decreases. boron deficiency After the leaves open, the growth point is damaged or dies or axillary buds germinate to form plants, the growth is abnormal, the plants are short, and the stems have brown hook longitudinal striations. After the formation of the flower disk, the stem supporting the flower disk loses the ability to follow the sun, some always hang their heads, some always face upwards, the lower old leaves are plump and dark green, the upper leaves are small and curly, the mesophyll loses green, and the veins are prominent. Click for more sunflower cultivation technology Click for more food crop cultivation technology