Metabolomics, phytohormone and transcriptomics strategies to reveal the mechanism of barley heading date regulation to responds different photoperiod oleh Zhuo Ga, Liyun Gao, Xiruo Quzong, Wang Mu, Pubu Zhuoma, Xiongnu Taba, Guocheng Jiao, Dawa Dondup, Lhundrup Namgyal, Zha Sang