Effects of clone and fertilization on the seed and foliar chemical composition of Scots pine (Pinus sylvestris) grafts

Effects of clone and fertilization on the seed and foliar nutrient concentr ations of Scots pine grafts were investigated in a seed orchard in southern Finland. The seed and foliar samples for chemical analyses were collected during win ters 1985-86 and 1988-89 from 39 grafts per clone fertilized in spring 1986 . There were 6 clones and 13 treatments for each clone with three replicati ons. The treatments consisted of N, P, K in various combinations, micronutr ients, wood ash and grass control. Macro-(N, P, K, Ca, Mg) and micronutrien ts (Cu, Zn, B) were analysed. There were statistically significant differences between the clones in seed nutrient concentrations. The variation of the K, Mg, Ca, Zn and Cu concent rations between the two study years was considerably larger in the seeds th an in the needles. The concentrations of these elements in the seeds were l ow in the year of an abundant seed crop in spite of fertilization. This had , however, no negative effects on germination of seeds. The proportions of crude fat and crude protein were high in both years (34% and 35% in 1985; 3 3% and 38% in 1988). Fertilization had only minor or no effect at all on th e seed chemical composition in the orchard with a satisfactory nutrient sta tus of the soil. Also on the foliar nutrient concentrations the effect of t he clone was stronger than that of fertilization. Grafts with large needles produced heavy seeds, which had more storage proteins than the lighter see ds.