Short-Term Hypergravity-Induced Changes in Growth, Photo synthetic Parameters, and Assessment of Threshold Values in Wheat (Triticum aestivum L.)

The reduction in growth and development of plants constantly exposed to different ranges of hypergravity (acceleration more than 1 g) is adequately documented. However, earlier studies did not reveal the threshold hypergravity value at which these effects were seen. The understanding of the threshold g-value is an important consideration while we plan hypergravity experiments as different plants can perceive and respond differently at the same g-value. The aim of the present work is to study the effect on growth and photosynthetic parameters as well as to assess the threshold values in wheat seedlings grown from hypergravity-exposed seeds. Healthy wheat seeds were immersed in distilled water for 24 hours and exposed to hypergravity values ranging from 200 g to 1,000 g for a short duration of 10 minutes and sown on 0.8% agar gel. All the measurements were done on the fifth day after sowing. Results obtained showed significant reduction in growth and photosynthetic parameters in seedlings raised from hypergravity-treated wheat seeds. Interestingly, the reduction was started at 400 g and was found to reach a maximum at 1,000 g. Probably this would be the first study reporting the threshold of high g forces for growth and photosynthetic parameters when seeds were exposed to hypergravity.