Agrilife Research-Bred Winter-Hardy Hibiscus Nearer To U.S. Markets

Dr. Dariusz Malinowski,Kay Ledbetter

Five winter-hardy hibiscus lines nurtured from tiny stem tip clippings to foot-wide flowers could see commercialization in 2015 through research overseen by Dr. Dariusz Malinowski, Texas A&M AgriLife Research plant physiologist and forage agronomist in Vernon.

The winter-hardy hibiscus breeding program was initiated in 2009 at the Texas A&M AgriLife Research and Extension Center in Vernon.

“We have been extremely successful with disclosing more than 130 unique lines of hibiscus with very unusual flower color and shape and leaf color that are not available yet on the market,” Malinowski said.

“We have about 50-60 of them, almost half of them, under evaluation by commercial partners in the U.S. and Europe,” he said. “We believe the first five of our lines should be sold in 2015 in the U.S., and in 2016 and 2017 there will be more sold in the U.S. and in Europe by our commercial partners.”

Dr. Dariusz Malinowski, Texas A&M AgriLife Research plant physiologist in Vernon, shows off a large winter-hardy hibiscus in his breeding program. (Texas A&M AgriLife Research photo by Kay Ledbetter)

The hibiscus can basically be grown from South Central Texas to Canada, as long as the required winter period is long enough for them to go dormant after the first frost, Malinowski said. The plants resprout from the root the following spring.

Malinowski is joined on the hibiscus research by Dr. Bill Pinchak, AgriLife Research animal nutritionist, and Steve Brown, Texas Foundation Seed Service program director. The hibiscus research is conducted under the AgriLife Research program’s strategic plan covering non-traditional or under-utilized crops that have value because of drought tolerance.

“We have evaluated more than 6,000 plants since the breeding program started, and over 100 have a commercial value and will be propagated further,” he said.

Malinowski said their breeding program starts with propagating enough plants in the greenhouse for commercial companies to evaluate. Initially, Malinowski said he worked with tissue cultures, but that proved to be very expensive, so now he propagates them from cuttings.

“After we identify a plant that has nice flowers and it is of commercial value with the characteristics we like, we begin the vegetative propagation process,” he said. “We had about 99 percent success last year.”

Many lines are being looked at in the Texas A&M AgriLife Research winter-hardy hibiscus breeding program near Vernon. (Texas A&M AgriLife Research photo by Kay Ledbetter)

The hibiscus breeding process starts with cuttings of the stem tips treated with rooting hormones and planted in a mixture of peat moss and perlite into six-pack containers under a misting system, Malinowski said. After about two weeks, the young plants start to root and grow. They are allowed to grow under a misting system for another two weeks to make them stronger.

The young plants are then moved from under the misting system and continue to grow for another two weeks to get stronger and harden a bit, he said. They will begin to put on flower buds during this stage. They are then removed from the six-packsand planted individually in pots.

“This is how we prepare the copies for evaluation by our commercial partners,” Malinowski said.

“Once these companies decide they wish to include these lines in their product offering, they will license the products and propagate to begin to increase their numbers,” Brown said.

Different petal shapes and colors are being selected for in the Texas A&M AgriLife Research winter-hardy hibiscus breeding program near Vernon. (Texas A&M AgriLife Research photo by Kay Ledbetter)

“In the ornamental crops business, most commercial nurseries will show their customers a sampling of what will be available for the next season,” he said. “This is an effort to both promote the product and get an idea of how many plants they need to produce for the upcoming season.”

Malinowski said full-grown copies of the best plants growing in the field are kept in a separate greenhouse to make new hybrids for next year’s evaluation. The advantage to the greenhouse is there are no insects and no cross-pollination, so they can precisely define which plants are crossed.

“We were the first to create a blue winter-hardy hibiscus, and we now have lines with more and less blue and in different shapes,” Malinowski said. “The blue flowering lines have small flowers and we have been working to increase the flower size and maintain the blue color. This year we have the first line with blue flowers that are 8 inches in diameter.”

A true blue flower pigment does not exist in the winter-hardy hibiscus species, he said, but through crossing breeding lines with purple and lavender flower colors, they have been able to establish the blue-tinted flowers.

In addition, his breeding program has developed a number of unique flowers, both in color and size.

“We work on the size of flowers. We want flowers that are at least 12 inches in size,” Malinowski said. “We have magenta, dual colored white and pink, and now we have a rare mutation with a white-eyed flower.”

While he said he has still not been able to get the white eye on a red flower, a very difficult transfer to make in the breeding process, that is one of his next goals.

“We have the first lines with red flowers and a small white eye,” Malinowski said. “The next step will be increasing the size of the white eye to achieve a nice contrast with the red petals.”

Source : agrilife.org