Artificial Selection for Seedling Drouth Tolerance in Boer Lovegrass (Eragrostis curvula Nees)1

Abstract

Artificial selection and evaluation of boer lovegrass (Eragrostis curvula Nees), were conducted with a program‐controlled environment at the Tucson Plant Materials Center. Plants from 16 sources were stressed for seedling drouth tolerance, and 216 surviving plants were progeny evaluated. Experimental 3‐17 showed significantly higher survival than any other selection and exhibited three times the seedling drouth tolerance of A‐84. Evaluation under artificial conditions of growth was repeated for the extreme selections and relative ranking of the selections did not change. These findings confirmed the use of program‐controlled environment for consistent evaluation of large numbers of seedlings and for precise selection of superior genotypes.The usefulness of this technique to select genotypes with superior seedling drouth tolerance was demonstrated by performance under natural environments of rangeland seeding trials. Evaluations of experimental 3‐17, A‐84, and A‐68 lehmann lovegrass (E. lehmanniana Nees) were conducted on a limited basis at Pima, Ariz. in 1967 and more extensively in 1968 at several sites in southeastern Arizona. Stand density under natural environments of rangelands of experimental 3‐17 was superior to A‐84 and its seedling drouth tolerance was equal to that of lehmann lovegrass for all sites in the Southern Desert Shrub of Arizona.