Lyhytpäiväkrysanteemin pistokasmonistus- ja taimikasvatuskokeista

anglais. The experiments carried out at K. Vakkuri’s nurseries at Hyvinkää in accordance with the research programme of the Horticultural Department of the University of Helsinki were designed to study 1) the influence of rooting media and hormone treatment on the rooting of chrysanthemum cuttings in circumstances in which automatic watering cannot be provided, and 2) the effect of propagation treatment of cuttings on the quality of the crop. In the rooting experiments sand, soil, Vermiculite, peat and sand, as well as previously used peat and sand media were used. Tested varities, Silvertone, Halo and Indianapolis, yielded the best results on sand and Vermiculite media, which produced a thick rooting system in the cuttings (Tables 1 and 2). In these media the roots furthermore developed a shape suitable for replanting (Fig. 1). Hormone treatment increased significantly the number of the roots (Table 2), but had hardly any effect on the length of the roots or stem. In the used peat sand rooting media the cuttings either developed no roots at all, or, if roots started growing, they turned brown at once. This was probably due to the poisonous effect of the decaying products in the peat. In the propagation treatment experiment on cuttings the quality of the crops yielded by potted cuttings and those planted in boxes was compared directly with that of cuttings planted directly into their flowering quarters. Each cutting was grown with three stems. Three varieties, Silvertone, Halo and Buckskin, were used in the experiment. It was found that both the propagation treatments, potting and planting in boxes, clearly lowered the quality of the crop (Tables 3, 4, 5). The shoots of these cuttings showed a slower rate of growth after pinching, and furthermore, they produced significantly smaller quantities of first class flowering stems, there were fewer blooms per stem and the flowering began later than in cuttings planted directly into their flowering quarters.

finnois. Vahvin ja muodoltaan paras juuristo kehittyi krysanteemin pistokkaisiin vermikuliitti- ja hiekka-alustoilla. Rootone 9:llä käsittelyn ansiosta muodostui krysanteemin pistokkaisiin erittäin vahva ja hyvämuotoinen juuristo sekä juurtuminen varmentui. Versohaaran pituudella lyhytpäiväkäsittelyä aloitettaessa ei ollut ratkaisevaa merkitystä kukinnan onnistumiseen. On kuitenkin ilmeistä, että voimakkaasti alkuun lähteneet versot antavat paremman sadon kuin hennot ja hitaasti alkuun päässeet. Kasvuston kehitys oli nopeinta ja laadullisesti paras sato saatiin silloin, kun lyhytpäiväkrysanteemin taimet istutettiin suoraan kasvupaikalleen. Näin ollen on pistokkaiden käsittely niiden juurruttua pyrittävä supistamaan yhteen uudelleen istutuskertaan, sillä juuristo vioittuu herkästi, mistä taas on seurauksena kasvun hidastuminen ja sadon laadun heikkeneminen.