ISSN:
1573-5060
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Summary 144 alfalfa (Medicago sativa L.) introductions were classified into eight groups based on their origin, winterhardiness, leafhopper yellowing, and growth characteristics. We studied the performance of crosses within and between these groups. General (GCA) and specific combining ability (SCA) for persistence among the eight groups were about equal. The Chilean group had a high positive GCA for persistence, suggesting that it may be become a good source of germplasm for persistance and, perhaps, disease resistance. SCA for forage yield was about three times greater than GCA, indicating a large amount of non-additive gene action for yield in crosses between groups. In general, crosses between groups yielded more than crosses within groups. The Afghan group showed high GCA with all groups, suggesting that Afghan introductions may contribute to improved synthetic varieties. The Flemish introductions performed well in crosses within their group and also in crosses between groups. GCA for rapid recovery after cutting was six times greater than SCA, indicating largely additive gene action for this trait. Nonhardy and Afghan-like introductions contributed most to rapid recovery in hybrid combinations. GCA for fall growth was slightly larger than SCA. The nonhardy introductions showed a large positive GCA, along with a significant SCA for fall growth. The evidence of specific combining ability, particularly for forage yield, suggested that hybridization may be needed for adequate evaluation of alfalfa introductions. An introduction grown in a new environment often will perform poorly, but its hybrid progeny from crosses to other introduced or adapted strains may show superiority.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00032745
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