Effects of NaCl salinity on miniature dwarf tomato ‘Micro‐Tom’: II. Shoot and root growth responses, fruit production, and osmotic adjustment¹

Supported in part by Illinois Agricultural Experiment Station (Projects 65–353 and 65–363); The Horticulture Research Institute; University of Illinois College of Agriculture Office of Resident Instruction; and the Fred Gloeckner Foundation. Dr. J. Scott's (Univ. Florida Institute of Food and Agriculture Science, Gainesville) generous donation of ‘Micro‐Tom’ seeds and Dr. W.L. George's (University of Illinois College of Agriculture) helpful suggestions regarding experimental design and culture are greatly appreciated.

Abstract

The growth and production of miniature dwarf tomato selection Lycopersicon esculentum ’Micro‐Tom’ plants grown from seedling to harvest in solution batph culture’ at four different NaCl salinity levels (2.4 [control, no NaCl], 7.6, 12.8, or 18 dS‐m^‐1 solution conductivities) was monitored. Incremental reductions in canopy extent and shoot area of ‘Micro‐Tom’ were observed with increasing solution NaCl level. Root growth and shoot height were somewhat less responsive to imposed salinity. Fruit number, fruit size, and leaf tissue osmotic potential decreased as NaCl concentration increased. Fruit yield was highly correlated with total canopy and shoot area, but not with tissue osmotic or total water potential. ‘Micro‐Tom’ plants survived and continued fruit production at higher salinity levels despite reduced canopy growth. Treatment effects on vegetative growth and fruit production became more pronounced later in the growth cycle.

Notes

Supported in part by Illinois Agricultural Experiment Station (Projects 65–353 and 65–363); The Horticulture Research Institute; University of Illinois College of Agriculture Office of Resident Instruction; and the Fred Gloeckner Foundation. Dr. J. Scott's (Univ. Florida Institute of Food and Agriculture Science, Gainesville) generous donation of ‘Micro‐Tom’ seeds and Dr. W.L. George's (University of Illinois College of Agriculture) helpful suggestions regarding experimental design and culture are greatly appreciated.

Associate Professor and Professor (corresponding author) of Plant Physiology and Assistant Professor of Controlled Environment Agriculture, Department of Horticulture, University of Illinois.

Assistant Professor in Plant Tissue Culture and Physiology, Jordan University of Science and Technology, Irbid, Jordan.