**3.7. Triticale**

re‐evaluated; however, this appears to be a potential source of lower DON levels. A variety of FHB responses are shown in **Figure 6**, following the point inoculation of four tritordeum

**Table 5.** DON content (ppm) of amphiploids between *Triticum turgidum* (AABB) and *Hordeum chilense* (HH).

**Mean + SD Range**

The amphiploids show normal meiotic behaviour, are stable and perfectly fertile with perfect transmission of all chromosomes. There is no meiotic pairing between *Hordeum chilense* chro‐ mosomes and those of wheat. In order to induce pairing between homoeologous chromosomes, the amphiploid was crossed to the Capelli *Ph* mutant then backcrossed once to place the mutant in a homozygous recessive condition. The progeny resulting from the *Ph* mutant treatment

content and desirable agronomic traits was practiced during this procedure. Seventeen BC3

F4

generation. Selection for reduced DON

F4

amphiploids plus a Roblin check.

**Strain DON content**

68 Wheat Improvement, Management and Utilization

HT‐8 0.32 + 0.05 0.27–0.37 HT‐10 1.24 + 1.52 0–2.76 HT‐18 2.52 + 3.36 0–5.88 HT‐31 2.31 + 0.71 1.60–3.02 HT‐47 1.62 + 1.92 0.26–3.54 HT‐166 6.83 + 6.01 6.82–12.84 HG‐174 1.83 + 2.01 0.54–3.75 Medora 8.83 + 2.01 6.66–10.54

were further backcrossed and advanced to the BC3

**Figure 6.** FHB symptoms on spikes of Tritordeum lines at 21 days after inoculation.

Triticale, a wheat‐rye amphiploid is used primarily as a feed grain worldwide, but has never reached its true potential. For a feed grain, DON content is a highly significant component. It has been shown that for each ppm of DON, feed consumption by monogastric animals decreases by 7.5%. Triticale was considered to be a major carbohydrate for bio‐fuel produc‐ tion because of its high yields of biomass and tolerance to poor soils. Some consideration has been given for triticale to be used for ethanol production. However, it has been shown that the DON content in distiller's grains can be three lines as high as in the original grain. Therefore to fully realize the potential of triticale, its DON content must be reduced.

In general, triticale strains are notorious for poor FHB resistance. To put a wider perspective on this problem, we started by acquiring 371 strains of triticale from Plant Gene Resources of Canada (PGRC) to begin FHB testing. The testing was done in an epiphytotic nursery to evalu‐ ate Type II resistance. Visual rating of incidence and severity was done on the field plots and aliquots of seed ground for DON analysis. For the majority of the strains tested, the incidence and severity values exceeded 50%. Seven of the best strains were selected and shown in **Table 7**.

As shown in **Table 7**, the DON values of the seven strains ranged from 2.1 to 7.7 ppm, com‐ pared to Sumai3 at 1.2. The DON values in 2007 were low overall in that year. They were somewhat higher in 2008, ranging from 3.2 to 9.0.

AC Ultima was used a check triticale cultivar. It was a recently licensed cultivar in Canada and superior for most agronomic traits. Its DON content was 17.5 in 2007 and 16.0 in 2008.

The triticale strain TMP16315 was selected for further study. It was tested at numerous loca‐ tions across Canada and proved to be stable in its reaction to FHB. Its pedigree is undefined, but believed to originate from a Polish gene pool.

A study was initiated to identify the QTL combining the FHB resistance/lower DON levels. Line TMP16315 was crossed to AC Ultima. A mapping population of 150 DH lines using microspore culture (Francois Eudes pc) method was produced from the F1 hybrid. The


**Table 6.** DON content (ppm) in progenies of intercrosses between *Tritordeum* (ABH) and *Capelli Ph* mutant followed by backcrosses to durum cultivar AC Strongfield.


**Table 7.** FHB symptoms and DON content of seven best resistant accessions of triticale and the checks Sumai3 and AC Ultima in the field nursery in 2007 and 2008.

mapping population in three replicates was grown at three locations in eastern Canada and data collected on incidence severity, FDK and DON content. The QTL for the various FHB related traits will be determined from these data.

#### **3.8. Rye**

In screening of numerous accessions of rye from numerous sources, we were not able to find any lines with even minor improvements in FHB resistance. There were reports of Brazilian land races of rye with improved levels of FHB resistance [29]. The lines were evaluated for resistance by plating on media containing from 10−3 to 10−6 M levels of DON [32] to evaluate their levels of tolerance to DON. Lines that showed no variable effects on a medium contain‐ ing 104 –10−3 M DON were considered to be resistant, whereas lines showing retarded growth on media containing 10−5–10−6 M levels of DON were considered to be susceptible. As shown in **Table 8**, the landraces from Poula Frontin were susceptible to DON, whereas landraces from Lagoon Vermellia and Sao Paulo gave a resistant reaction. A number of the resistant lines were used as pollen parents on wheat cultivars Encruzilhada, Maringa, Max and NyuBay to produce octoploid amphiploids (as shown in **Table 9**).


**Table 8.** Tolerance of Brazilian rye landraces to deoxynivalenol (DON) following plating on DON‐containing media.

Potential of Wide Crosses to Improve the Resistance to Vomitoxin Accumulation in Wheat Following Infection... http://dx.doi.org/10.5772/67272 71


**Table 9.** Reaction of octoploid triticale strains to deoxynivalenol (DON) following plating on DON‐containing media.

One amphiploid combination with wheat cultivar Max gave a resistant reaction and five amphiploids with NyuBay were also resistant by growing in a medium with a 10−3 level of DON [12].
