Grain Filling And Stem Accumulation Effects On Durum Wheat (triticum Durum Desf.) Yield Under Drought

In Mediterranean area, water deficit is the main factor limiting agricultural production. Durum wheat yield is greatly hampered by drought in the Mediterranean semi-arid areas. The duration and the rate of grain filling and the contribution of stem assimilates are likely to have important effects on yield performance under stress conditions. The objective of this study is to evaluate differences in durations and rates of grain filling and the contribution assimilates from the stem to the yield of 10 durum wheat genotypes (Triticum durum Desf.). Water stress was induced in booting stage by stopping irrigation, the differences of duration and rates of grain filling and the contribution of the assimilates of the stems to grain yield were determined. Genotypes' agronomic performances were estimated by measuring yield components: number of grains per ear (NGE), weight of one grain (P1G) and weight of 1000 grains (PMG). The results showed a significant effect of water stress, genotypes and of the interaction between genotype x water stress. A positive correlation between agronomic performance and the two key variables for the final grain weight: the rate and duration of grain filling was observed.