Effects of Genotype and Environment on Seed and Forage Yield in Fenugreek (Trigonella Foenum-Graecum L.) Grown in Western Canada (Report‪)‬

Introduction Fenugreek (Trigonella foenum-graceum) is an annual legume crop whose seed is traditionally used as a spice, in artificial flavoring and in the production of hormones (Duke 1981; Jorgensen 1988; Jongebloed 2004; McCormick et al. 2006; Acharya et al. 2006 a,b; 2007 a,b, 2008). The crop is currently grown in India and parts of west Asia, north Africa, Mediterranean Europe, Australia, Argentina, United States of America and Canada (Acharya et al. 2006 a). Some genotypes of this species are adapted for growth under the rain-fed conditions found in western Canada (Acharya et al. 2007 b, 2008). However, earlier fenugreek cultivar development activities in western Canada were mainly focused on development of early maturing and high seed yielding genotypes for the spice market (Dr. A.E. Slinkard, pers. comm. 2007). Recent studies indicate that fenugreek developed in western Canada can also be used as a forage crop since the plant maintains high nutritional quality irrespective of its maturity and the forage does not cause bloat in ruminants (Mir et al. 1997 a,b). Fenugreek is an important source of diosgenin and soluble fibre (Fazil and Hardman 1968; Taylor et al. 1997; Basu et al. 2008) both of which contribute to its medicinal properties. The occurrence of diosgenin in livestock feed can enhance carcass weight (Acharya et al., 2006 a; 2007 a,b, 2008) and as an annual legume it is easy to incorporate into short term rotations where perennial forage legumes do not fit. Despite the fact that fenugreek has been identified as a forage crop, few adapted cultivars/ lines are available for successful forage production on the Canadian prairies. Tristar is the first forage fenugreek cultivar developed by Agriculture and Agri-Food Canada (AAFC) at the Lethbridge Research Centre (LRC), Alberta, for its ability to produce high biomass yield consistently over the years and locations. This cultivar is suited for intensive production of silage and hay in western Canada especially in regions with warm summers (Moyer et al. 2003; Acharya et al. 2006 b, 2008). However, Tristar fenugreek is slow to mature under adverse conditions, making it difficult to obtain seed for ongoing commercial production. In recent years, collaborative research between AAFC, University of Lethbridge and Alberta Agriculture, Food and Rural Development (AAFRD) has focused on use of a mutation breeding approach to identify new, early maturing fenugreek lines to help address this problem. It is widely accepted that genotype (G), growing conditions (E) and their interaction (G x E) are key factors in optimization of phenotypic traits in agricultural crops. However, if significant environmental effects exist, individual environmental parameters may be examined for their correlation to phenotypic traits (Moore et al. 2006). Eberhart and Russell (1966) proposed a model to test the stability of plant varieties under various environments, and defined a stable variety as having unit regression over environments and minimum deviation from regression. Adaptability of a genotype over diverse environments is usually tested by the degree of its interaction with different environments under which it is planted. A genotype or variety is considered to be more adaptive or stable if it has high mean yield but a low degree of fluctuation in yielding ability when grown over diverse environments (Muhammad et al. 2003). Genotype x environment interactions for various traits have previously been studied by different researchers in various crops including chickpeas (Jain and Panya 1998; Muhammad et al. 2003), dry beans (Balasubramanian et al. 1999), hard winter wheat (Moore et al. 2006) and sunflowers (Leon et al. 2003). However, information on seed and forage yield of fenugreek lines is extremely limited. This study was conducted to elucidate the effect of G, E, and G x E on seed and forage yield of newly identified fenugreek lines, by quantifying their individual contributions to yield v