Fig. 2

Assembling the growth chamber. a Two strands of fishing line are placed against a full-length coverslip, approximately 1 mm apart. b The fishing line is affixed to the coverslip with thin strips of laboratory tape. c Seedling is laid against agar block while coverslip is rotated such that the fishing line side faces the seedling. d Coverslip is laid against seedling/agar, which is facing up to facilitate positioning the root inside the 1 mm gap between fishing line strands. The seedling is thus sandwiched between the agar and coverslip. e Seedling, agar, and coverslip combination are rotated (flipped over) such that the agar block is now on top of the coverslip. f A plastid lid is placed over the seedling and agar block to prevent them from drying out. g The points of contact between lid and coverslip are sealed with micropore tape to further ensure moisture retention and prevent contamination