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F Salisbury

Publications and source records attributed to F Salisbury.

4 recordsLinked to original sources

[Cytoembryologic studies of super dwarf wheat grown in "Svet" greenhouse in the ground-based experiments].

The Project of scientific programs MIR/SHUTTLE and MIR/NASA was allowed for studying the productional, cytoembryological, morphological, biomechanical and other characteristics of superclub wheat on cultivation in the Svet greenhouse on-board orbital complex. This work was aimed at studying the duration of the complete cycle of ontogenesis of wheat and its individual stages, the peculiarities of forming the reproductive organs, processes, fertilization and formation of the seed production while cultivating in the Svet greenhouse under terrestrial conditions. Superclub wheat has been the object of experimentation. On cultivation of superclub wheat in the Svet greenhouse at designated conditions it was found that the cycle duration "from seed to seed" was 90-97 days. The number of granules in the wheat-ears studied was quite low and ranged from 15 to 30%. Performed studies with applying the light microscopy have indicated that in superclub wheat the embryological processes occur in compliance with those regularities which are described for the other forms of soft wheat.

Biomechanical Phenomena↗

"From seed-to-seed" experiment with wheat plants under space-flight conditions.

An important goal with plant experiments in microgravity is to achieve a complete life cycle, the "seed-to-seed experiment." Some Soviet attempts to reach this goal are described, notably an experiment with the tiny mustard, Arabidopsis thaliana, in the Phyton 3 device on Salyut 7. Normal seeds were produced although yields were reduced and development was delayed. Several other experiments have shown abnormalities in plants grown in space. In recent work, plants of wheat (Triticum aestivum) were studied on the ground and then in a preliminary experiment in space. Biometric indices of vegetative space plants were 2 to 2.5 times lower than those of controls, levels of chlorophyll a and b were reduced (no change in the ratio of the two pigments), carotenoids were reduced, there was a serious imbalance in major minerals, and membrane lipids were reduced (no obvious change in lipid patterns). Following the preliminary studies, an attempt was made with the Svetoblock-M growth unit to grow a super-dwarf wheat cultivar through a life cycle. The experiment lasted 167 d on Mir. Growth halted from about day 40 to day 100, when new shoots appeared. Three heads had appeared in the boot (surrounded by leaves) when plants were returned to earth. One head was sterile, but 28 seeds matured on earth, and most of these have since produced normal plants and seeds. In principle, a seed-to-seed experiment with wheat should be successful in microgravity.

Arabidopsis↗

Preparations for CELSS flight experiments with wheat.

We are planning a short-term experiment with Superdwarf wheat on the U.S. Space Shuttle and a seed-to-seed experiment on the Russian Space Station Mir. The goals of both experiments are to observe effects of microgravity on developmental steps in the life cycle and to measure photosynthesis, respiration, and transpiration by monitoring gas exchange. This requires somewhat different hardware development for the two experiments. Ground-based research aims to understand plant responses to the environments in the space growth chambers that we will use (after some modification): the Plant Growth Unit (PGU) on the shuttle and units called Svet, Svetoblock 2, or Oasis on Mir. Low irradiance levels (100 to 250 micromoles m-2 s-1 at best) pose a particular problem. Water and nutrient supply are also potentially limiting factors, especially in the long-term experiment. Our ground-based studies emphasize responses to low light levels (50 to 400 micromoles m-2 s-1); results show that all developmental steps are delayed by low light compared with plants at 400 micromoles m-2 s-1. We are also testing various rooting substrates for the shuttle experiment. A 1:1:1 mixture of peat:perlite:vermiculite appears to be the best choice.

Aluminum Oxide↗