A code of conduct for supervisors of postgraduate students was released by the Ministry of Education on Wednesday after a few high-profile cases of misconduct that tarnished the reputation of postgraduate education in China.

Supervisors shoulder the primary responsibility in cultivating postgraduate students and the important task of nurturing high-end and innovative talent, the ministry said.

As the "bottom line" and "basic requirement" for supervisors' behavior, the code of conduct forbids them from having inappropriate relationships with students or verbally abusing them.

They should pay more attention to students' mental health, academic pressure and anxieties, and establish a good interaction mechanism with students, it said.

They should not purposely delay students' graduation or ask them to do things irrelevant to their academic study, it added.

The code of conduct also required supervisors to serve as role models for advanced degree candidates by upholding academic integrity, stressing the importance of academic standards and valuing others' academic work.

Supervisors should offer proper guidance during every step of graduate research and academic paper writing, from choosing a research topic to defending dissertations, it said.

Universities should hold violators accountable by limiting the number of students they can supervise or even disqualifying them from supervising any students, the ministry said, adding that those who seriously violate the code will be banned from teaching.

A postgraduate student at Dalian University of Technology in Liaoning province shared his frustrations in a posting on the Sina Weibo social media platform last month before committing suicide in a school laboratory.

The student said he had received little support and attention from his supervisor and was feeling "hopeless" about his research. He was also worried about graduating on time, which would break the "good tradition" of his group.

"In our online research group meeting, the supervisor looked at my research data and calmly said it was all meaningless," the post said.

In January 2018, Chen Xiaowu, a professor at Beijing's Beihang University, was fired after the school investigated a sexual harassment accusation made by a former female student on social media.

Chen Zhiwen, editor-in-chief of online education portal EOL, said the newly released code of conduct was a reaction to an increase in unfortunate incidents and tragic events stemming from unhealthy relationships between supervisors and students.

Given the mismatch of power dynamics between students and teachers, students were often in a disadvantaged position, leaving room for unethical supervisors to behave inappropriately, he said.

"China has 460,000 supervisors for postgraduate students, and it is imperative to get rid of the rotten apples that spoil the whole bunch," he said.