Specialist options in the arts have been dropped while general arts courses have seen their hours cut and the teaching staff reduced.
Recruitment is also getting worse. The number of trainees in music is down by 23 per cent this year, on top of last year's 16 per cent fall. Even English and drama are under-recruiting by 9 per cent.
"Art forms are disappearing from many teacher-training institutions just as surely as they are from many schools," said Rick Rogers, author of the report, due to be launched on Monday.
He called this a "vicious downward spiral" caused by down-grading of arts in the curriculum and a knock-on effect for college courses. The situation would get worse with students spending more time in schools during training. "They don't get a good arts experience," said Mr Rogers.
Ironically, the report coincides with the Government's drive to boost the arts. The Department for Culture, Media and the Arts published the report of the creative industries' task force last week and the Department for Education and Employment's national advisory committee on creative and cultural education is due out soon.
Mr Rogers fears that Circular 498 on initial teacher training with its emphasis on literacy and numeracy, has allowed even more cuts in hours allocated to the arts. In a survey of a third of the 101 ITT providers in England, the RSA found the arts being squeezed out, especially for primary teachers.
At secondary level, art is in reasonable health, but music, dance and drama are vulnerable. In 19978 art under-recruited by 6 per cent; music by 16 per cent and design and technology by 42 per cent. Estimates for 19989 show further deterioration - art is under target by 12 per cent; music by 23 per cent and design and technology by 57 per cent. English and drama is down by 9 per cent compared with 1 per cent in the previous year.
"The arts are in retreat. If current trends continue, the arts are likely to end up in small enclaves with a handful of training institutions operating as centres of arts excellence with not much going on elsewhere," comments the report.
The RSA wants the departments of culture and education, inspectors and the Teacher Training Agency to work in partnership to ensure that teachers have arts training and experience. Schools should play a vital role in reversing the downward spiral as trainees spend much more time on teaching practice.
"The disappearing arts? The current state of the arts in initial teacher training and professional development", RSA, 8 John Adam Street, London WC2N 6EZ, Price Pounds 7.50 including package and postage.
THE REPORT'S MAIN FINDINGS
* Widespread evidence that teacher-training institutions are abandoning specialisms in arts subjects and are cutting back on hours and staff.
* Inspections reveal that almost half of postgraduate teacher-training courses in the arts have significant weaknesses, especially music.
lNine out of 10 students on primary courses feel they have too little time on the arts.
* More than half of student teachers do not teach dance during their school placements; a third do not teach music.
* Many newly-qualified primary teachers say they have little confidence in teaching music and drama.
* In-service training in the arts has been severely reduced because of national curriculum changes in primary schools.
* In the Teacher Training Agency's new three-year contracts with providers of in-service training, only 1 per cent of student places has been allocated for courses in art, music, dance or drama.
* Only 6 per cent of specialist schools are dedicated to the arts (19 out of 330).