University of Nebraska, College of Agric. The Agric. Expt. Station Bulletin SB 428.
Chrysanthemum Improvement (1955)

Glen Viehmeyer & Roger D. Uhlinger
Emeritus Professor of Horticulture and Associate Professor of Horticulture and Forestry
University of Nebraska North Platte Station, North Platte, Nebraska

"Water culture" method of breeding.

Because of limited greenhouse facilities at the North Platte Station, a water culture method of hybridizing has been used extensively. This method was discovered by accident when a small bouquet of flowers for pollen collection was allowed to remain in a water-filled jar for the remainder of the season. During seed harvest, this bouquet was examined and found to have set abundant seed. With this background, a number of crosses were made on cut flowers in the fall of 1951 and a good crop of seed resulted. Much of the hybrid seed for the North Platte project is produced by this method.

In using the water culture method, sprays of flowers are collected just before pollen is shed. These are placed in ordinary glass fruit jars filled with tap water and are left there until seed has ripened. Water lost from the jars by evaporation and transpiration is replaced as necessary and insects are excluded from the room. It is not essential that the cut flowers receive full sunlight during the period of pollination and seed maturation. Seed has been produced in a vegetable cellar without light. Advantages of the method are:

  1. No glasshouse is needed. Any room where temperatures can be held above freezing will serve and seed set appears to be as good in near darkness as in full sunlight.
  2. Much less space is required. An ordinary card table will provide room for 15 or 20 different varieties, a number that would require 60 to 80 square feet of greenhouse bench.
  3. Crosses can be made more rapidly and easily, since containers can be moved about to fit the convenience of the operator. The work can be done while seated in a comfortable chair.
  4. Seed set and viability are equal to that produced in the conventional manner and seed matures in two to four weeks less time.
  5. Insect control is easier.

Crossing operation.

The work of crossing chrysanthemums is facilitated by shearing the petals from the flower head to expose the pistils. Properly done, this will reduce the pollination time by as much as 90%. Shearing is best done in the late bud stage.