Nitrogen effects on SPAD meter and grain yield relationships in F۲ durum wheat populations

This study was conducted to evaluate the effectiveness of SPAD-۵۰۲ chlorophyll meter reading as indirect selection criteria for grain yield under different nitrogen (N) conditions in F۲ durum wheat populations. In this study six durum wheat parents and their ۶x۶ half-sib F۲ diallel cross populations were grown under N۰ (zero N), N۱ (۱۲۰ kg/ha) and N۲ (۲۴۰ kg/ha) nitrogen conditions. Chlorophyll content at heading stage was obtained by using SPAD meter (SPAD-۵۰۲; Minolta, Osaka, Japan). SPAD readings and grain yield of durum wheat increased with increasing nitrogen level. Genotypic variation for grain yield and SPAD was found to be highest in N۱ and N۲ levels, respectively. General combining ability (GCA) effects were significant for plant grain yield in N۱ conditions, while significant for SPAD in N۱ and N۲. Significant specific combining ability (SCA) effect was observed only SPAD readings in N۲ condition. High GCA/SCA ratio showed that additive genes have significant role at SPAD values of N۱ and N۲. Grain yield correlated with SPAD of N۰ (R۲ = ۰.۳۲۸). The results indicate that genotypic differences for SPAD reading among F۲ durum wheat progenies can be effectively detected in high nitrogen condition.This study was conducted to evaluate the effectiveness of SPAD-۵۰۲ chlorophyll meter reading as indirect selection criteria for grain yield under different nitrogen (N) conditions in F۲ durum wheat populations. In this study six durum wheat parents and their ۶x۶ half-sib F۲ diallel cross populations were grown under N۰ (zero N), N۱ (۱۲۰ kg/ha) and N۲ (۲۴۰ kg/ha) nitrogen conditions. Chlorophyll content at heading stage was obtained by using SPAD meter (SPAD-۵۰۲; Minolta, Osaka, Japan). SPAD readings and grain yield of durum wheat increased with increasing nitrogen level. Genotypic variation for grain yield and SPAD was found to be highest in N۱ and N۲ levels, respectively. General combining ability (GCA) effects were significant for plant grain yield in N۱ conditions, while significant for SPAD in N۱ and N۲. Significant specific combining ability (SCA) effect was observed only SPAD readings in N۲ condition. High GCA/SCA ratio showed that additive genes have significant role at SPAD values of N۱ and N۲. Grain yield correlated with SPAD of N۰ (R۲ = ۰.۳۲۸). The results indicate that genotypic differences for SPAD reading among F۲ durum wheat progenies can be effectively detected in high nitrogen condition.

کلیدواژه ها:

Diallel ، Durum wheat ، GCA ، SCA ، SPAD reading