Submitted to: American Society of Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 8/15/2006
Publication Date: 11/12/2006
Citation: Loffredo, E., Palazzo, A.J., Senesi, N., Clapp, C.E. 2006. Seed germination and seedling early growth of two native varieties of slender wheatgrass as affected by soil humic acids [abstract]. ASA-CSSA-SSSA Annual Meeting Abstracts. ASA-CSSA-SSSA Annual Meeting. Nov. 12-16, 2006. 2006 CD ROM.
Technical Abstract: The ERDC-CRREL research program for developing methods for more rapid establishment of native plants on western and eastern US military lands to avoid possible competition by invasive weeds during the initial year after seeding. One aspect is whether the presence of humic acids (HAs) may make native grasses more competitive when grown in combination with introduced grasses. The objective of this work was to evaluate the effect of three HAs isolated from two Wyoming soils (GN and GS) and one Utah soil (D) in suspension at two concentrations (10 and 100 mg/l) on seed germination and early seedling growth. The plants used were two varieties of slender wheatgrass: the commercial cultivar Pryor and the SERDP-select germplasm line developed by ERDC-CRREL to be more resilient to military training. Seeds were germinated for 6 days in Petri dishes in the dark at 20°C; the seedlings were grown for 21 days in controlled temperature, humidity and illumination conditions in a Fitotron chamber. All experiments were conducted in five replicates. Statistical analysis of data by ANOVA showed that the HA origin and concentration affect seed germination and early growth of both slender grass varieties to different extents. In particular: (a) the three HAs at both concentrations, and especially D-HA, exert a general slightly positive effect in promoting germination of both varieties, especially of the SERDP-select germplasm; (b) the three HAs, especially at the higher concentration, increase the length and fresh and dry weights of shoots of the Pryor variety seedlings, whereas only GN-HA at the lower concentration increases the root weight; (c) with the exception of the negative effect exerted by GN-HA at the lower dose on root and shoot dry weights, the other parameters measured for the early growth of the SERDP-select variety appear not be significantly affected by any HA at any concentration.