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As a new synthetic species, triticale has been widely used for food and feed. Lodging is a severe problem in triticale production, and it is unknown whether wheat height‐reducing genes can improve lodging resistance in triticale. In this study, the wheat‐dwarfing genes Rht12and Rht‐B1bwere introgressed into hexaploid triticale (AABBRR) lines to understand their effect on plant height. The results showed that Rht12and Rht‐B1breduced the plant height of triticale plants by 37.7 and 29.9%, respectively. Rht12and Rht‐B1bboth had significant effects on the basal internode's length, diameter, and thickness, which may greatly improve lodging resistance. Additionally, the net photosynthetic rate was increased by 28.7% in Rht12dwarf lines. However, Rht12had a significant and negative effect on thousand‐kernel weight (14.5%) and yield per plant (20.6%). On the other hand, Rht‐B1breduced the number of tillers by 19.6% and yield per plant by 18.1% with no negative effect on the harvest index. Furthermore, Rht12and Rht‐B1bdecreased grain plumpness but improved several grain quality traits. Conclusively, Rht12and Rht‐B1bimproved lodging resistance but had some negative effects on yield components, which need careful consideration in triticale breeding. Rht12and Rht‐B1bsignificantly reduced plant height in hexaploid triticale by 37.7 and 29.9%, respectively, while improving internode characteristics.Rht12and Rht‐B1bdecreased trait values of some yield components, and Rht‐B1bdid not affect the harvest index.The net photosynthetic rate of flag leaves was significantly increased in Rht12dwarf triticale lines at the filling stage, while there were no notable changes in the Rht‐B1bdwarf lines.

Rht14, was considered as a GA‐responsive dwarf gene in durum wheat (Triticum durumL.). The object of this paper is to understand the responsiveness of Rht14after applying exogenous GA3on important morphological and agronomic traits, and its potential application in wheat breeding. In this study, the F2:3lines, F3:4lines and F4:5lines derived from the reciprocal crosses between the Castelporziano (CP), the donor of Rht14, and tall cultivar Langdon (L) were used to evaluate the effects of Rht14with exogenous GA3application on crucial traits. After application of GA3, the plant height of the dwarf lines was more significantly increased by an average of 51.21% and 52.27% than that of the tall lines by 14.70% and 15.16% of the two populations, respectively, while their diameter and thickness of internodes were remarkably reduced, and their flag leaf area, SPAD value and net photosynthetic rate were markedly decreased, compared with the controls. After application of GA3, the spikelet number spike−1, grain number spike−1, and 1000‐kernel weight of the dwarf lines notably increased, while no significant differences were observed on the seed length, width and thickness. Exogenous GA3significantly increased the coleoptile length, whereas notably reduced the max root length and total root length of the dwarf lines. Significant increases of crude protein, wet gluten, sedimentation value, stability time and development time were observed in the dwarf lines treated with GA3. This study indicated the dwarf gene Rht14was a GA‐deficient gene and application GA3could rescue some negative effects by Rht14.

Wheat alien chromosome addition lines possess abundant genetic resources and they are usually used for transferring desired genes or traits into wheat. The screening and characterisation of addition lines for target traits is one of the prerequisites for efficient utilisation of the alien chromosomes. In order to understand the properties and potential utilisation of wheat addition lines, the effects of additional chromosomes on agronomic and photosynthetic traits of common wheat were evaluated using 34 addition lines with the same genetic background of Chinese Spring. The results showed that most of the alien chromosomes decreased plant height (61.8%) and grain number per spike (47.1%), whereas some increased spike length and tiller number. Alien chromosomes of Agropyron intermedium G, Elymus trachycaulus T5HL5HL, El. trachycaulus 5SS and Haynaldia villosa 1V performed well in improving yield components. None of the alien chromosomes studied had negative effects on photosynthetic traits. Higher net photosynthetic rates were observed in Aegilops umbellulata 5U, El. trachycaulus 5H and rye 1R addition lines. Regarding seedling traits, 21 lines (61.8%) showed improvement in different root traits, whereas 26.5% of the chromosomes decreased coleoptile length. Addition lines with better performance for some specific traits were identified and discussed.