The most cost effective ways are often simple to operate too.
But they are not overnight successes without any cost.
They arise from blend of long experience with new system and innovations.

Photoautotrophic

Vermiculite and Paper Pulp as Supporting Materials for Micropropagation

(From the September, 2000 issue of Agricell Report) F. Afreen-Zobayed and collaborators at Chiba University and Nisshinbo Industries Inc. have compared the use of agar with the use of a mixture of vermiculite and paper pulp for photoautotrophic micropropagation of sweet potato plantlets (Plant Science 157(2):225-231, 2000). Afreen-Zobayed et al. found that plantlets grown on vermiculite mixed with 30% paper pulp show the best growth. The root and shoot fresh weight of these plantlets are 2.7 times greater than those grown on agar, and the leaf, stem and root dry weights are at least twice those of plantlets grown on agar. The net photosynthetic rate per plantlet is also highest in plantlets grown on the vermiculite-paper pulp mixture. Growth is significantly better in plantlets grown on the vermiculite-paper pulp mixture than on vermiculite alone, but is better on vermiculite alone than on agar. After transfer to ex vitro conditions, plantlets grown on mixtures containing various proportions of vermiculite and paper pulp show survival percentages ranging from 90% to 100% whereas the survival percentage of those cultured on agar is only 73%.

For further information: F. Afreen-Zobayed, Laboratory of Environmental Control Engineering, Faculty of Horticulture, Chiba University, Matsudo, Chiba 271-8510, Japan. Fax: 81 47 363 1286.

Photoautotrophic Micropropagation of Rose Plantlets under CO₂ Enriched Conditions

Makio HAYASHI, Hou-Ching LEE and Toyoki KOZAI

Summary

CO₂ enrichment under a high photosynthetic photon flux density of 150 µmol m^-2 s^-1 ,
which is 2-3 times that in conventional plant tissue culture, was effective for promoting growth of miniature rose (Rosa hybrida Hort., cv Mary Antwernett) plantlet in vitro.

Growth was greater under photoautotrophic conditions than under photomixotrophic conditions.

Photoautotrophic growth was greater when CO₂ concentration in the culture room was higher.