Effect of growth regulators on yield and fiber quality in ramie (Boemheria nivea (L.) Gaud.), China grass

The effects of two mixtures of four plant growth regulators (choline chloride, gibberellin (GA(3)), benzyladenine (6-BA)and NaHSO3) at 20:9.5:800 mg kg(-1) (H1) and 20:42:43:2350 mg kg(-1) tH3) (active ingredients), respectively, were investigated on yield and fiber quality in ramie (Boehmeria nivea (L.) Gaud.). The mixtures were sprayed over the canopy at two growth stages (10 and 20 days after the previous cut) of field-grown ramie. The treatments increased raw fiber yield by 13-18%, and improved fiber fineness by 57-349 m g(-1), increased number of leaves per plant, and also improved all yield components. Treatment H1 resulted in a denser distribution, smaller diameters and greater quantity of fiber cells in stem cross-section. Physiological responses included improving leaf water status, increasing net photosynthetic rate, and decreasing electrolyte exosmosis rate. (C) 2001 Elsevier Science B.V. All rights reserved.