STIMULATING EFFECTS OF SOME CHEMICAL AND PHYSICAL TREATMENTS ON THE GROWTH OF CARNATION

Carnation production is increasing favorably and ranks second among cut flower production in Japan. As the cultural problems, it is important to establish early a lot of thick branches at lower nodes, to secure high dry-matter production and root activity, to give heat tolerance and to reduce drooping of cut flowers especially in hot growing season.

Soil application of rice blast controlling agents, isoprothiolane (diisopropyl-1,3 dithiolan-2-yldenemalonate) accelerated remarkably the secondary branching at lower nodes and the elongation of branches and increased also the early and the total numbers of cut flowers.

Foliar spray of BA (6-[N-benzyl] aminopurine) was available to increase secondary branches at lower nodes.

A damping-off controlling agents, hydroxyisoxazol (3-hydroxymethyl-isoxazole) with methalaxyl (methyl-N-[2-methyl]-N-2,6-xylyl]-DL-alaninate) used by soil application could retain higher ratio of green leaves at the basal part of the stem for long growing period.

Nicotinamide soil application enhanced dry-matter production and increased the weight and the length of cut flower.

For the alleviation of heat stresses, soil application of ascorbic acid, nicotinamide and phthalimide was effective, and foliar spray of NAA with GA was also effective to reduce the dropping of cut flower.

Mulching with reflective film accelerated the secondary branching at lower nodes and increased the yields conspicuously.