THE RELATIVE SINK STRENGTH OF HYPOCOTYLS AND PETIOLES OF BRUSSELS SPROUTS UNDER DIFFERENT DAY AND NIGHT TEMPERATURE REGIMES

Transplants of Brussels sprouts were raised under different day- and night-temperature regimes to see whether the elongation growth and dry matter production of the plants were influenced by the difference between day and night temperature.
The diurnal mean temperature was 19°C in all treatments.
Four replicates of the experiment were done in growth chambers with fluorescent tubes as the only light source, and one replicate was done in a glasshouse in March/April with supplemental light from high-pressure sodium lamps.

Petioles and hypocotyls were shorter under the negative temperature difference compared to the constant temperature and the positive temperature difference.
These plant parts were shorter partly because less biomass (absolute and relative) was allocated to that type of tissue, and partly because the specific length (length to weight) of the hypocotyls and petioles was lower under this treatment.
This means that the investment in leaf tissues was higher under the negative temperature difference than under the other temperature regimes.
The relatively higher sink strength of petioles and hypocotyls under positive temperature difference seemed to cause less productive and slower growing plants compared to the other treatments.

Workshop on Environmental Regulation of Plant Morphogenesis

A.K. Bakken, M. Flønes

Brassica oleraceae L. var. gemmifera DC, dry matter partitioning, elongation growth, temperature difference

https://doi.org/10.17660/ActaHortic.1995.378.12