THE BORON NUTRITION OF POPPIES (PAPAVER SOMNIFERUM L.) ON KRASNOZEM AND ALLUVIAL SOILS OF TASMANIA

In Tasmania lime is often applied to heavy krasnozem and light alluvial soils of pH 5 to 6 which are used for the production of poppies (Papaver somniferum L.). Although liming may increase yields it may also induce boron deficiency.

A glasshouse experiment initially tested calcium hydroxide applied alone on krasnozem at the equivalent of up to 50 t/ha.
Other glasshouse experiments tested factorial combinations of uniformly mixed calcium hydroxide at zero, 2.5 and 5 t/ha with band-placed sodium borate at zero, 2 and 20 kg/ha boron.
Field experiments tested zero and 2 kg/ha boron band-placed or foliar-sprayed, with calcium carbonate at zero and 2.5 t/ha.

On alluvial soil 2 kg/ha B increased yield and boron concentration of stem and leaves mainly at 2.5 and 5 t/ha Ca (OH)₂ but 20 kg/ha B was completely toxic.
On krasnozem even 50 t/ha Ca²(OH)₂ did not induce boron deficiency.
The 2 kg/ha B was ineffective but surprisingly 20 kg/ha B increased vegetative yield and the boron and nitrogen concentration of stem and leaves.

In a field experiment on the same alluvial soil plants showed acute boron deficiency.
The 2 kg/ha B band-placed increased capsule + seed yield by 700% and when foliar-sprayed the increase was 500%. Both methods decreased the Ca : B ratio in leaves from 3500 to about 500. Calcium carbonate increased stem and leaf morphine concentration by 36% with no reduction in tissue boron.
In another field experiment on krasnozem 2 kg/ha B had no effect on any characteristics.

II International Symposium on Spices and medicinal Plants

J.C. Laughlin

https://doi.org/10.17660/ActaHortic.1980.96.22