8th INTERNATIONAL WHEAT CONFERENCE

The mean value of LV at low N rate was 1231ml; LV ranged from 1050 ml for cv. Sava, an
old Serbian cultivar, to 1340 ml for cv. Bezostaya 1, an old introduced cultivar. The mean
LV at high N rate was 1300 ml, LV ranged from 1105 for cv. Banatka to 1415 ml for cv.
Balkan. Mean difference between the two fertilization levels was 69 ml. Mean LV across
four growing seasons and two N treatments was 1266 ml, with significant difference between
the average values of the cultivars, ranging from 1088 to 1363 ml. The average rate of increase in
LV per year of release, estimated from the slope, was 3.96 ml year -1 . The relative annual
genetic gains in LV of wheat cultivars over 50 years were 0.31%. It was 3.43ml year -1 or
0.28% at the low level of N input, and 4.47ml year -1 or 0.34% at the high level of N input.
Newer cultivars, selected at intensive agricultural practice expressed higher positive reactions
at increased N nutrition.
The results suggested that modern cultivars have better N use efficiency. Also, it can be
concluded that even protein content decreased, changes in protein qualitative composition,
along with the balancing of other parameters, resulted in the overall improvement
of quality.
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