The disomic families d4A, d5A, d3B, d5B, d6B and d7B had the same heading date as the euploid control variety Milturum 553 (52 plus or minus 1 days). The disomic families d3A, d6A, d7A, and d5D headed 5-6 days earlier than the control; the families d2D and d6D were 5 days later. The variability within the disomic families from the same monosomic plant was recorded only for d4D: d4D-1 and d4D-2 had 47 plus or minus 1 and 55 plus or minus 1 days to heading, respectively. Only the families d5A-2 and d4D-2 exhibited no significant differences from the variety Milturum. 553 in the other traits studied (Table 1). The number of quantitative traits in which the rest d-families differed from the control varied from one to two (d3B-4, d5B-1, d5B-7, d7B-7, and d6D-2) to six to seven characters (d3A-7, d6A- 4, d6A-9, d7A-1, d7A-5, and d5D-5). Accounting each trait separately or taking into consideration all the traits, the percentage of the families that showed significant differences from the control was highest in the families derived from monosomics for A genome chromosomes; intermediate and lowest, in D and B genome families, respectively (Table 2). The main stem length (plant height) and the plant yield (grain weight per plant) are the only exceptions. The families derived from the monosomics for B genome displayed higher variation of these traits than the disomic pedigrees of the monosomics for D genome. The most variable traits were the following: the stem length, the main spike and plant yields. The length of the upper internode and the number of grains in the main spike were the least variable traits. Increased values of the parameters were recorded in the disomic families compared with the euploid control in the majority of observations. Only the number of spikelets in the main spike was less in ten of eleven disomic families compared with the control. The spikes with a decreased spikelet number had yet an increased grain number. It resulted from the increased number of fertile flowers in a spikelet, thereby increasing the grain number per spikelet and grain yield per plant (families d3A-7, d6A-4, d6A-9, d7A-1, d7A-5, and d5D-5). Thus, the increased main spike yield (measured in gram) resulted from both the increased grain weight due to intense grain filling and the increased number of fertile flowers (Table 1).

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