تأثير تحوير المصدر والمصب وموضع الحبة على السنبلة على وزن الحبة في القمح الصلب Triticum durum تحت الظروف البعلية

الملخص EN

This experiment was conducted during 2014/2015 season at the experimental station of the Faculty of Agriculture, University ofTripoli.

The aim was to study the effect of source-sink manipulation on grain weight of two lines and a check variety of durum wheat (Triticum durum).

The split-split plot design in completely randomized blocks with three replications was implemented.

Main plots were assigned to the genotypes, subplots to source-sink manipulation treatments and sub-subplots to the effect of grain position within the spike on grain weight.

Plants depended on the rainfall only.

At maturity, the grain weight on the three positions within the spike (base, middle and apical) was measured.

Generally, results showed that the lines (ICARDA-13 and ICARDA-23) produced heavier grains than Karim (57.09, 57.49 and 50.95 mg) respectively.

The effect of the grain position within the spike was also statistically significant with (57.86, 55.24 and 52.44 mg) of the middle, base and apical spikelets respectively.

The effect of the source-sink manipulation treatments was not statistically significant which means that the assimilates availability in control shoots was sufficient to fully satisfy grain growth requirements.

However, there was a trend of grain weight to be reduced by decreasing the assimilate availability (flag leaf removal) and in a greater way when increasing the assimilate availability (half spikelets removal) which led to produce heavier grains comparing with the control spikes.

This effect was most apparent in Karim variety than both lines.

Thus, present results show that the variety Karim is source limited and it is possible to improve its yield genetically by increasing its potential grain weight through source size improvement.