Seedling treatments and phosphorus solution concentrations affect nodulation and nodule functions in soybean (Glycine max L.)

S.J. Miao, X.Z. Han, X.B. Liu, Y.F. Qiao
2008 Plant, Soil and Environment  
The effect of three seedling treatments: T<sub>0</sub>, normal germination; T<sub>1</sub>, cotyledons removed; T<sub>2</sub>, cotyledons removed 5 days earlier than in T<sub>1</sub>; and two phosphorus levels (P<sub>0</sub> and P<sub>30</sub>) on nodulation and nodule function in soybean [<i>Glycine max</i> (L.) Merr.] were investigated in nutrient solution culture. The number of nodules formed at P<sub>0</sub> was in the order T<sub>2</sub> > T<sub>0</sub> > T<sub>1</sub>, but it was
more » ... ut it was T<sub>0</sub> > T<sub>2</sub> > T<sub>1</sub> at P<sub>30</sub>. Nodule dry weight per plant had the same tendency as the nodule number. Nodule size (dry weight per nodule) in seedlings ranged from 0.601 to 1.089 mg in the order T<sub>0</sub> > T<sub>1</sub> > T<sub>2</sub>, regardless of P level. For example, nodule size in T<sub>0</sub> was larger by 86% and 52% than T<sub>2</sub> at P<sub>0</sub> and P<sub>30</sub>, respectively. Furthermore, regardless of P level, a specific acetylene reduction activity (ARA, &micro;M C<sub>2</sub>H<sub>4</sub>/h/g nodule) increased with P content in seedlings, but no significant difference was found (<i>P</i> < 0.05). Leghemoglobin (Lb) content was not significantly affected by P level; however, seedlings (T<sub>0</sub> and T<sub>1</sub>) significantly affected the Lb content per unit plant biomass (<i>P</i> < 0.05). All these results suggest that seedling P content plays a key role in nodulation and nodule function of soybean.
doi:10.17221/2301-pse fatcat:m6nij5qxsvdejkle63ttkapoly