양버들 × 황철나무(Populus nigra v. italica × Populus maximowiczii) F₁의 生長과 特性에 關한 硏究

The Growth Performance and Other Characteristics of P. nigra v. ita. × P. maximowiczii F₁

Superior poplar hybrid individuals were selected among the P. nigra v. ita.×P. maximowiczii F₁ populations. The survival of cutting, growth performance in response to spacing, morphology of leaf and specific gravity of wood have been observed up to the age of 9 under the same conditions. The results attained were as follows: 1. The three clones of the P. nigra v. ita×P. maximowiczii F₁ have shown better volume growth than P. euramericana I-476. They have shown a considerable difference in the growth performance among the clones and a remarkable hybrid vigor in the growth rate of the rooted cuttings. 2. It is not advisable to make selection for the growth superiority of hybrid poplars during their juvenile age. The evaluation of growth performance of the hybrid poplars is considered to be made at least 7 years after planting. 3. The leaf size in width and length of P. nigra v. ita. × maximowiczii is intermediate between the parents, however, leaf surface tends to be resembled to the mother tree, P. nigra v. ita., wheras the dorsal side of the leaf tends to be resembled to it’s pollen tree, P. maximowiczii. 4. The wood specific gravity of P. nigra v. ita.×P. maximowiczii F₁ is slightly lower than that of P. euramericana I-476, shaving 0.380 and 0.441 respectively.