Gene expression in tissues of root tips from Pinus pinaster seedlings under ammonium nutrition

In the present study, the gene expression changes in four different tissues of root tips from maritime pine were analyzed. The roots were under two nutritional conditions (only watered or fertilised with 3 mM of ammonium) and harvested after 24 hours of the treatment. Pine seedlings were subdivided into two groups. The control group was irrigated with 80 mL of water (C), the second group was supplied with 80 mL of 3 mM NH4Cl. Root samples were collected 24 houres after the irrigation. Seedling’s root tips were cut and tissues of 5 - 6 mm were imbibed in a specimen holder with Tissue‐Tek optimal cutting temperature embedding medium (Sakura Finetek, Alphen aan den Rijn, The Netherlands) and immediately frozen in liquid nitrogen for cryostat sectioning. The 24 samples were sequenced on an Illumina NovaSeq 6000 as paired-end reads of 150 bp length.