Growth responses of Spartina patens and Spartina alterniflora by means of a two dimensional factorial design

Growth of Spartina patens and Spartina alterniflora was compared under identical greenhouse conditions. Mature plants were grown in quartz sand and watered with the following solutions: (1) full Hoagland's solution; (2) Hoagland's minus iron; (3) Hoagland's minus nitrogen; (4) Hoagland's with NaCl added to 28 o/oo; (5) sea water of 28 o/oo. S. patens showed improved growth in Hoagland's solution and Hoagland's minus iron, but showed significantly less growth in solutions 3, 4 and 5. S. alterniflora showed no significant difference in growth in the treatment cultures. General trends which were shown are: (1) S. patens grew better under low iron levels while S. alterniflora's growth was only slightly enhanced under low iron conditions, and (2) growth of both species was reduced more due to saline conditions than to a lack of nitrogen.