Flag leaf reflectance (FLR) and senescence (S)
In this study flag leaf reflectance was measured at Red (654 nm), Blue (450 nm) and Green (500 nm); as shown in Table 2, analysis of variance revealed that the reflectance at different wavelengths (Red, Blue and Green) was highly significant genotypes effects (P < 0.001). Reflectance at Red ranged from 29.98% for G19 to 45% for G1 with an average of 35.8% over all genotypes; for this parameter the good genotypes are those we have the lowest values such as G19. The local genotypes have the highest values with a global mean of 37.84%. In addition, the mean of the reflectance at Blue in the introduce genotypes was 30.19% and in the local genotypes was 30.02% with a total mean of 30.22%. The lowest value of the reflectance at Blue registered in the genotype G22 this one was in the same homogenize group of G11, G15 and the local genotype Saida 183 (G 24), there was no significant difference for the reflectance at Blue between the local and introduce genotypes. As shown in Table 2, the parameters of senescence there was significant difference between genotypes. The values of the mean senescence varied from 34.96% for the introduce genotype G12 to 66.05% for G 17 (introduce genotype) with total mean of 56.19%. The analysis of variance based on the origin effects showed the absence of difference between the local and introduce genotypes for all senescence parameters. The preferable genotypes were those which have low values for the mean senescence and senescence velocity; based on this raison the best genotype was the introduced genotype G12. The data of the Table 3 demonstrate that the best genotypes were the genotype which in the top of the ranking list. Based on the indices of FLR and S the best genotypes were G22, G15, G11, G5, G19, G17 and G18, respectively. The total score of the genotypes based on the all parameters demonstrated that the best genotypes were G11, G12, G5, G15 and G18, respectively. Spectral reflectance measurements have been successfully used to estimate biomass, leaf area index, photosynthesis and/or yield in several species of trees
(Richardson et al., 2001), bread wheat
(Filella et al., 1995) and durum wheat
(Aparicio et al., 2004). Ferrio et al., (2005) showed that the higher grain yield was correlated with lower reflectance are visible. The results of
Guendouz et al., (2013) indicated the potential of using flag leaf reflectance wheat yield prediction.
GY, TKW and chlorophyll content (Chl)
The genotypes effect was significant for the grain yield and thousand-kernel weight (Table 2). The values of grain yield varied between 43.09 q/ha for the introduce genotype G20 to 74.4 q/ha for the local landrace Fouarra. Based on the test of means comparison the genotypes with highest GY were G1, G2, G3, G7, G12 and local landrace Fouarra; in addition, the highest TKW was registered by the introduced genotype G12. The homogenize group of genotypes which have the highest TKW were G12 and the local landrace Saida 183. For the chlorophyll content and as shown in Table 2 the analysis of variance showed a significant effect of genotypes, the highest values registered by the introduced genotype G5 this one was in the same homogenize group of G2, G4, G8 and G18. Based on the origin of genotypes the analysis of variance demonstrated that the reflectance at Red, Green and the chlorophyll content there were significant difference between the two groups (local and introduce), for this raison the highest values of Chl were registered by the introduced genotypes (Table 2). As shown in Table 4 the ranking of the genotypes was based on the rank of each genotype for Senescence and Chl, GY and TKW parameters; the best genotypes were G5, G12, G11, G7, G3 and G2, respectively. The study of correlation showed a negative correlation between the mean of senescence, GY and TKW (r = - 0.63***, r = - 0.59 **, respectively); this correlation in good agreement with
Rawson et al., (1983) and
Ellen (1987). Contrary to these findings many studies have demonstrated that delayed senescence delays remobilization and leads to reduced grain weight
(Yang et al., 1997).