Freesia Research Articles

Study on quality and quantity aspects of some new Freesia cultivars in the second year of culture.

Freesia hybrida is one of the most cultivated cut flowers worldwide. Modern technologies recommend cultivating Freesia in rotation with chrysanthemum and tomatoes, to avoid pests and diseases apparition into culture of that are the main cause of species degeneration. The greatest expenses in a Freesia culture from bulbs are made on the achievement of the bulbs but they compensate the quality and quantity of the flowers. In our research, the cultivars have been cultivated in a modern greenhouse and as we couldn’t do a rotation of crops, we prevented their apparition into culture by thermal disinfection of soil before setting the crops and pest control by preventing them with several treatments recommended in this matter. The results show that the lowest number of flower stalks was recorded by ‘Striped Sun’ cv. while ‘Troubadur’ cv. has shown a higher number of floral stalks in the second year. Other researched aspects have shown a diminution of the values to the first year. The greatest diminution of the floral stem length was recorded by ‘Algarve’ cv. while ‘Yvonne’ cv. has recorded greater values of the same character in the second year. The degeneration appeared different to the researched cultivars on the aspects mentioned in the paper, even if all had benefited of the same cultural conditions.

FLORICULTURE IN KOREA: OPPORTUNITIES AND CHALLENGES FOR COLLABORATIVE RESEARCH

Korea has a rich history of floricultural practices and innovations with a long tradition of research and development, some of the notable accomplishments include the breeding and genetic improvement of flowers. The floriculture industry in Korea has developed since the Seoul Olympic Games in 1988 (Hyang Young Joung et al., 2003). Flower consumption greatly differs from one country to another, depending on the economic potential, on the mentality and life style of people, but not only on these. Regarding the consumption of the floral production the cut flowers occupy 45% of the overall ornamental crop production. Potted plants come next with 35%, followed by bedding flowers 8%, ornamental trees 6 %, flowering trees 4% and others flowers with 2%.The main cut flowers are Rose, Chrysanthemum, Lilium, Carnation, Gypsophila, Gerbera, Freesia and Gladiolus. In Korea, the most popular are cut flowers for celebration (Orchids: 53%) and for decoration are the Potted Plants in 47%.

A Study of Self-Interstitial Atom in W by Means of Low-Temperature Irradiations

To clarify the migration behavior of self-interstitial atoms (SIA's) in W, we have performed anelasticity measurements of W after 2 MeV electron irradiation at 5 K and after 20 MeV proton irradiation at 1.5 K. Dislocation pinning results observed during irradiation clearly show that free SIA's in W migrate below 1.5 K. Warm-up measurements after irradiation reveal higher temperature pinnings which all show no dose shift as reported for substages of the stage I in the electrical resistivity measurements after low-temperature electron irradiation, suggesting that these pinnings are due to SIA's released from traps. After the present results, one can say that the migration temperature of free SIA's in the refractory BCC metals is, in general. very low as below 1.5 K in W and below 6 K in Nb and Ta with the exception of about 40 K in Mo.

Virus diseases of Freesia in Italy

Virus diseases of Freesia in Italy

Evidence for a soilborne nature of freesia leaf necrosis

In een tweetal experimenten kon worden aangetoond dat de infectie van knolfreesia’s plaatsvindt vanuit de grond (Tabel 1). Infectie treedt ook op als de knollen in verterende resten van freesiaplanten worden gepoot (Tabel 1). Een groter aantal zieke planten wordt gevonden wanneer de freesiaplanten worden geteeld in natte grond (Tabel 2). Temperatuur blijkt ook van invloed te zijn: bij 16°C traden meer infecties op dan bij 12°C. Omdat we het pathogeen nog steeds niet hebben kunnen isoleren en mede gelet op de wijze van verspreiding, zou men mogen veronderstellen dat de verwekker van bladnecrose bij freesia veel gelijkenis vertoont met bobbelbladvirus bij sla.

Production of virus-free freesia's by means of meristem culture

Door middel van meristeemcultures werd getracht virusvrije planten te verkrijgen van vijf Freesia-varieteiten. Hiertoe werden meristemen uitgeprepareerd en op verschillende voedingsbodems geplaatst (Fig. 1). Op een medium ontwikkelde zich een aantal meristemen tot normale planten, op de andere media vertoonden de cultures soms een overmatige wortelontwikkeling. Veertien meristemen groeiden uit tot planten (Tabel 1, Fig. 2), waarvan na serologische toetsing er zes virusvrij bleken te zijn.