EFFECT OF CHLOROPICRIN AND OTHER SOIL DISINFECTANTS ON THE NITROGEN NUTRITION OF THE PINEAPPLE PLANT

Abstract

The nature of the effect of soil disinfectants such as chloropicrin, steam and formaldehyde, alone and in combination, on the nitrogen nutrition of the pineapple was studied. Since root pathogens assume only a minor role in the soil used, the influence of treatment is principally on the nitrification process in the soil and its influence on the N nutrition of the plant. Total N absorbed by the plant by the end of 43 weeks was correlated with the amt. of ammonium available in the soil and not with nitrate availability or accumulation, indicating a greater rate of absorption of NH4 than nitrate N. Associated with the high absorption of NH4 was an increase in the growth rate, succulence, chlorophyll conc. and total dry matter of the leaves.