2013 Volume 51 Issue 2 Pages 79-84
Leaflet inclination angle before paraheliotropism controls seed production of soybean plants. We examined the effect of water condition on the inclination angle of leaflets and petioles of two soybean cultivars. Angles measured in the morning were larger in 2008, a wetter season, than in 2009, a drier season. Angles were similarly larger in irrigated plants than in unirrigated plants. The imposition of drought stress on plants grown in pots reduced these angles with the decline in water content of these tissues. There were significant correlations between inclination angle and water content in leaflets and petioles of plants grown both in the field and in pots. These results indicate that water condition controls leaflet and petiole inclination.