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De-domestication is a unique evolutionary process during which crops re-acquire wild-like traits to survive and persist in agricultural fields without the need for human cultivation. The re-acquisition of seed dispersal mechanisms is crucial for crop de-domestication. Common wheat is an important cereal crop worldwide. Tibetan semi-wild wheat is a potential de-domesticated common wheat subspecies. However, the crucial genes responsible for its brittle rachis trait have not been identified. Genetic mapping, functional analyses and phylogenetic analyses were completed to identify the gene associated with Qbr.sau-5A, which is a major locus for the brittle rachis trait of Tibetan semi-wild wheat. The cloned Qbr.sau-5A gene is a new Q allele (Qt ) with a 161-bp transposon insertion in exon 5. Although Qt is expressed normally, its encoded peptide lacks some key features of the APETALA2 family. The abnormal functions of Qt in developing wheat spikes result in brittle rachises. Phylogenetic and genotyping analyses confirmed that Qt originated from Q in common wheat and is naturally distributed only in Tibetan semi-wild wheat populations. The identification of Qt provides new evidence regarding the origin of Tibetan semi-wild wheat, and new insights into the re-acquisition of wild traits during crop de-domestication.

Salicylic acid (SA) is a key defense hormone associated with wheat resistance against Fusarium head blight, which is a severe disease mainly caused by Fusarium graminearum. Although F. graminearum can metabolize SA, it remains unclear how this metabolic activity affects the wheat&ndash, F. graminearum interaction. In this study, we identified a salicylate hydroxylase gene (FG05_08116, FgNahG) in F. graminearum. This gene encodes a protein that catalyzes the conversion of SA to catechol. Additionally, FgNahG was widely distributed within hyphae. Disrupting the FgNahG gene (&Delta, FgNahG) led to enhanced sensitivity to SA, increased accumulation of SA in wheat spikes during the early infection stage and inhibited development of head blight symptoms. However, FgNahG did not affect mycotoxin production. Re-introducing a functional FgNahG gene into the &Delta, FgNahG mutant recovered the wild-type phenotype. Moreover, the expression of FgNahG in transgenic Arabidopsis thaliana decreased the SA concentration and the resistance of leaves to F. graminearum. These results indicate that the endogenous SA in wheat influences the resistance against F. graminearum. Furthermore, the capacity to metabolize SA is an important factor affecting the ability of F. graminearum to infect wheat plants.

This paper introduced the principle of one dual closed-loop DC motor speed control system with fuzzy PID controller. The algorithm could reduce the setting time and the over-shoot of the step response of the speed-current loop control system, with comparison of the traditional PID after simulation.

This paper was presented a new method to compute structured singular value μ, which had been used widely to analyze and synthesize robust controller with structured uncertainty. The formulated method was adaptive Newton pathfollowing to find an optimal singular path at some frequency for low-order function of μ-Δ(M). The objective of the new algorithm was to calculate structured singular value conveniently and stably and finally design a better robust controller.

Cooperative pointing and tracking is one important characteristic of deep space intersatellite laser communication, so that the dynamic mathematical model is complicated nonlinearity and coupling. The contribution of this paper is to substitute the time-domain error transfer function of state equations and to linearize the state space for the sake of physical realization easily in terms of previous authors' work. The method applied is state feedback and coordinate transformation in nonlinear field, the calculated result is demonstrated that differential equations modeled can be transferred into canonical controllable form and realized physically. © (2014) Trans Tech Publications, Switzerland.

This paper was presented one new modified controller scheme for inertial gyro control system. Based on Narendras hybrid adaptive law, the modified algorithm was variable metric that took use of parameter matrix Γk to obtain two updating laws in turn online. The key modified contents were: 1) the output y (t) was passed by one low-pass filter, 2) the parameter was updating in term of one proper initial Γ0 and the measurable values. The objective of the proposed new adaptive robust control schemes was to achieve fast convergence of parameter updating, and promise good robust stability of control system during tracking, reduce the tracking error at start-time with filtered output.