Author
Submitted to: Agronomy Abstracts
Publication Type: Abstract Only Publication Acceptance Date: 7/22/2003 Publication Date: N/A Citation: N/A Interpretive Summary: Forage kochia (Kochia prostrata) is a perennial semi-shrub used for forage, habitat, and greenstrips in the western U.S. It grows in extremely salty soils throughout Eurasia and 'Immigrant', the only cultivar in the U.S., is known for its growth in salty and alkali soils throughout the Intermountain West. In this study we conducted a greenhouse study to compare the relative salt tolerance of Immigrant with forage kochia accessions from Kazakhstan. In 2001 and again in 2002, seedlings of 15 entries were started in cone-tainers plugged with capillary matting and filled with silica sand. Flats were dipped twice weekly in a complete fertilizer solution. Six weeks after planting, NaC1 and CaC12 were added to the solution. Salt concentration started at an EC of 3 and was increased 3.0 units weekly until an EC of 54 was reached. A unit combining time and dose (ECday) was created by summing the EC level of each 24 h period. Probit analysis was used to determine the lethal dose for 50 percent mortality (LD50). Rand correlation between the years was high (r=0.89) validating the methods. Entries differed significantly with Immigrant being less salt tolerant than most Kazakhstan entries. These results suggest that forage kochia accessions from Kazakhstan could be used in a breeding program to improve salt tolerance. Technical Abstract: Forage kochia (Kochia prostrata) is a perennial semi-shrub used for forage, habitat, and greenstrips in the western U.S. It grows in extremely salty soils throughout Eurasia and 'Immigrant', the only cultivar in the U.S., is known for its growth in salty and alkali soils throughout the Intermountain West. In this study we conducted a greenhouse study to compare the relative salt tolerance of Immigrant with forage kochia accessions from Kazakhstan. In 2001 and again in 2002, seedlings of 15 entries were started in cone-tainers plugged with capillary matting and filled with silica sand. Flats were dipped twice weekly in a complete fertilizer solution. Six weeks after planting, NaC1 and CaC12 were added to the solution. Salt concentration started at an EC of 3 and was increased 3.0 units weekly until an EC of 54 was reached. A unit combining time and dose (ECday) was created by summing the EC level of each 24 h period. Probit analysis was used to determine the lethal dose for 50 percent mortality (LD50). Rand correlation between the years was high (r=0.89) validating the methods. Entries differed significantly with Immigrant being less salt tolerant than most Kazakhstan entries. These results suggest that forage kochia accessions from Kazakhstan could be used in a breeding program to improve salt tolerance. |