A.N. Gromov
From numerous methodical problems of gladiolus hybridization the most important (from our point of view) are the questions of topophysis of a flower in a flowerhead.

It is known in the vegetable kingdom that one and the same organ of a plant can be of different quality depending on its topophysis. In this connection we have to answer the question whether the flowers of the same plant located on different orders of a stem are of different qualities in transferring certain characteristics in the process of gladiolus hybridization.

With this end in mind we have carried out a series of direct and reciprocal crosses of gladioli in different combinations. As a rule, all flowers on the spike were pollinated. The seeds from each pod of every test plant were sown separately.

The results were recorded during the second year of blooming. The inheritance of the following characteristics was registered: colour and its clarity; shape and colour of spot; shape and size of flowers; length of flower stalk; number of buds in the flowerhead; number of open flowers, substance of petals; strength of attachment of flower to the stalk.

Data on each separate characteristic of a seed progeny of three mother plants in every combination (3 repetitions) were liable to bio-metrical treatment.

For estimation of the seed progeny of every series of flowers (from the first to the 16th pod) we had at our disposal: up to 250 hybrid plants grown from the seeds taken from the pods of the lower and middle orders and about 100 hybrid plants derived from the pods of the upper portion of a stalk. The decreased number of the latter is attributed to the fact that in the upper flowers a lower number of ovaries is fertilized.

The reproductive organs of gladiolus flowers are also of different properties in relation to their biochemical indices dependent on the topophysis of flowers.

DOI: 10.17660/ActaHortic.1971.23.70

Acta Horticulturae