STUDIES OF MATURE SEEDS OF 11 PINUS SPECIES DIFFERING IN SEED WEIGHT .1. ELEMENT CONCENTRATIONS IN EMBRYOS AND FEMALE GAMETOPHYTES

Neutron activation analysis and spectrophotometric phosphorus analysis gave quantitative determinations of elements in female gametophytes a nd embryos from mature seeds of 11 Pinus species. High concentrations of P, K, Mg, and S and significant concentrations of Cl, Ca, Mn, Zn, a nd Fe were detected in both tissues. Within each species of Pinus, the total mineral nutrient concentrations in haploid female gametophyte s amples were similar to total mineral nutrient concentrations within di ploid embryo samples. Seed size and weight varied greatly among the 11 species of Pinus investigated. P and Mg concentrations in female game tophytes and (or) embryos were not correlated with seed weight. Inters pecific seed weight was negatively correlated with female gametophyte concentrations of S, Ca, Zn, and Fe, and also negatively correlated wi th embryo concentrations of Mn, Zn, and Fe. Interspecific seed weight was positively correlated with embryo concentrations of K and Cl. On a per tissue basis, larger seeded species contained higher total amount s of all the measured elements than small-seeded species.