Biomass allocation and nitrogen distribution of Pinus wallichiana Jackson seedlings under different nitrogen fertigation levels

Abstract

Pinus wallichiana seeds were sown in polybags filled with sterilized riverbed sand in 2010. Seedlings were thinned out to one seedling per polybag, which were treated weekly with Ingestad pretreatment nutrient solution for 4 weeks and then were fertigated with nitrogen levels of 0.99, 1.98, 2.97, 3.96, 4.95, 5.94, 6.93, 7.92, 8.91 and 9.90 mg and fixed levels of phosphorus, potassium, calcium and magnesium dissolved in 50 ml of water seedling -1 week -1 upto or until 28 weeks. Biomass allocation to needles, (separated by hand from shoot axis), stem (Includes hypocotyls and epicotyls) and roots increased significantly with the increase in nitrogen level and seedling age. At 7.92 mg level of nitrogen fertigation biomass allocation and nitrogen concentration partitioning at 28 weeks got increased by 190, 32 and 44%, and 179, 101 and 147% in needles, stem and roots, respectively as compared to control. Nitrogen concentration in shoot and root decreased at lower nitrogen level as seedlings age increased, but increased at higher nitrogen fertigation levels in needles, stem and roots. To the end of the experiment, nitrogen uptake per seedling increased, whereas, nitrogen use efficiency (NUE) decreased with the increasing nitrogen levels.

Intensification of cultivation of Pinus sylvestris L. seedlings with a closed root system in the Southern Urals

“…Various containers for cultivation are being tested [4], natural and artificial substrates [5][6][7]. The influence of growth stimulators [8][9], pre-sowing preparation of seeds [10][11][12] fertilizers at different stages of seedling development [13][14][15] and the importance of irrigation [16] are studied. To increase stress resistance, seedlings are grown with the addition of spores and cultures of ectomycorrhizal fungi to the substrate [17][18].…”