Evaluation of Selection Indices for Alfalfa (Medicago sativa L.)
In order to evaluate the efficiency of selection indices in alfalfa improvement, an experiment was conducted from 2000 to 2007 at East Azarbaijan Agricultural and Natural Resources Research Center, Iran. A set of 29 native ecotypes, which were collected in 2000 and 2001 from Azerbaijan (Iran), together with one improved variety were used to conduct a polycross nursery. For the purpose of random mating, a randomized complete block design was used with 12 replications arranged in this nursery. The resulting 30 half-sib families were planted individually in pots and the 30 days old seedlings were transplanted to the field in May, 2004. Each 3-row plot consisted of 45 HS plants. Several traits, such as individual plants’ fresh weight and individual plants’ dry weight (IPFW, IPDW), number of shoots per plant (NS) and plant height (PH) in each harvest and also, days until 10% flowering, the ratio of fresh and dry weight of leaves/plant and size of trifoliate leaves were measured for three cropping seasons. The results of analysis of variance showed large variation among polycross progenies. Six selection indices (Ii) with different number of traits at adult plant stage were evaluated. Based on the result of this investigation, if number of shoots and height of adult plant, excluding yield, are recorded, I2 is suggested. If, in addition to fresh yield, height of adult plant is measured, I6 is recommended. I4 is useful when number of shoots and plant height with dry yield are included in the index. In conclusion, the importance of mature plant traits in selection indices was in the order of yield > plant height > number of shoots. The results provided more evidence that selection indices incorporating the component of dry yield are more advantageous. The most efficient selection index consisted of NS, IPDW and PH, having a relative efficiency of 280%.
Papers published in Notulae Scientia Biologicae are Open-Access, distributed under the terms and conditions of the Creative Commons Attribution License.
© Articles by the authors; licensee SMTCT, Cluj-Napoca, Romania. The journal allows the author(s) to hold the copyright/to retain publishing rights without restriction.
Open Access Journal - the journal offers free, immediate, and unrestricted access to peer-reviewed research and scholarly work, due SMTCT supports to increase the visibility, accessibility and reputation of the researchers, regardless of geography and their budgets. Users are allowed to read, download, copy, distribute, print, search, or link to the full texts of the articles, or use them for any other lawful purpose, without asking prior permission from the publisher or the author.