Conservation and restoration efforts should incorporate knowledge of the specific genotype by environment interactions related to the managed species in order to ensure the success of the project.  Southern wild rice (Zizania aquatica) is an ecologically and culturally important aquatic grass found in isolated stands in the near shore habitats of lakes and rivers in the Midwest and along the eastern coast of North America.  This study examined the effects of water depth and seed provenance on the early growth of three Indiana wild rice populations (collected from two lakes) under greenhouse conditions in 2009.  Plants were grown at water depths of  46 cm, 23 cm, 0 cm, or at - 15 cm (where the last served as a drought treatment) and harvested either at the first floating leaf stage or 48 days after transplanting.

Results/Conclusions

Wild rice growth was affected by both water depth and seed provenance.  Dry weight (roots, shoots, leaves, and total), number of tillers, number of leaves, and leaf area were greatest in the 0 cm treatment and decreased with increasing water depth.  The growth of the drought treatment was either less than or not significantly different than that of the plants grown at 46 cm.  Differences in growth between lake populations were substantial, supporting the hypothesis that genetic differences among relatively isolated wild rice populations may influence the success of efforts to conserve this species.