The influence of transplanting on the growth of the tobacco crop

Abstract

In two field experiments at Mareeba, Queensland, the effects on the subsequent development of tobacco plants of the degree of root damage received at transplanting, and of the stage of development of the transplant, were investigated. Early leaf expansion was slightly delayed by severe root damage, and slightly advanced when damage was reduced. No lasting effects of either treatment were observed, however. Total elimination of root damage by use of pot-raised seedlings shortened the period between transplanting and flowering, and reduced the numbers of leaves initiated. The greater increase in area of the lower leaves compensated for the smaller leaf number, with the result that neither the yield of cured leaf nor the total leaf area of pot-raised plants differed appreciably from that of seedbed-raised plants. The treatment did, however, have an adverse effect on leaf quality. The more advanced the development of the seedling at transplanting, the greater was the number of lower leaves stunted by the associated stresses ; but the deficiency was always balanced by the increased expansion of the upper leaves. There were no consistent yield differences that could be attributed to these effects. The remarkable compensatory ability of tobacco is emphasized and discussed in relation to seedling treatment and climate.