Suspensions of plant cells in microgravity

Electrofusion of evacuolated with vacuolated mesophyll protoplasts of Nicotiana spec. was performed as part of the German Sounding Rocket Program (TEXUS). The results indicate a significant increase not only in the yield of 1:1 fusion products, but also in homo- and multifusion products. Heterokaryons obtained under microgravity have been shown to be viable to a higher degree with respect to their ability for light-dependent oxygen evolution (independent of other substrates than bicarbonate). Furthermore we were able to regenerate hybrid plants from suspensions of vacuolated and evacuolated protoplasts which were pulse-treated under microgravity. These expressed characteristics intermediate to those of the parental plants (Nicotiana tabacum (cv. Samsun), evacuolated; N. rustica, vacuolated).