Grain-filling, chlorophyll content in relation with grain yield component of durum wheat in a Mediterranean environment

Durum wheat (Triticum durum Desf.) is one of the more widely cultivated crops in the Mediterranean basin, where drought is the main abiotic stress limiting its production. This study was conducted on the experimental site of station ITGC in Sétif, Algeria to determine the duration and velocity of filling and its relationships with yield components and chlorophyll content of ten durum wheat genotypes. The SPAD-502 was used to measure the amount of chlorophyll (Chl) in the leaf, which is related to leaf greenness, by transmitting light from light emitting diodes (LED) through a leaf at wavelengths of 650 and 940 nm. Grain yield was negatively correlated with number of days to heading (DH) and positively with velocity of filling. The beginning of active phase of grain filling corresponded to the beginning of the degradation of chlorophyll content. The velocity of grain filling was negatively correlated to the number of days to heading (DH). Changes in photosynthesis most closely paralleled changes in chlorophyll content. All these changes occurred during the period of grain filling.