NEW YORK, Sept 21 (Reuters) - U.S. stocks were slightly higher on Tuesday after a broad sell-off the day before, but worries over troubles at developer China Evergrande and uncertainty ahead of Wednesday"s Federal Reserve policy news kept a lid on the market. Most major S&P 500 sectors were higher, led by gains in real estate (.SPLRCR). Concerns over Evergrande (3333.HK) acted as a boiling point for markets trading near record highs, amid coronavirus concerns and sluggish economic growth. All three major indexes were hammered on Monday. "People have been preconditioned to buy pullbacks for most of the last year plus," said Michael James, managing director of equity trading at Wedbush Securities in Los Angeles."But that overhead nervousness is still there, and that"s why we"re not seeing material further upside," he said. Investor focus on Wednesday will be on the results of the Fed"s policy meeting, where the central bank is expected to lay the groundwork to ease its stimulus, although the consensus is for an actual announcement to be delayed until the November or December meetings. read more The Dow Jones Industrial Average (.DJI) rose 66.18 points, or 0.19%, to 34,036.65, the S&P 500 (.SPX) gained 12.31 points, or 0.28%, to 4,370.04 and the Nasdaq Composite (.IXIC) added 89.32 points, or 0.61%, to 14,803.23. The S&P 500 index traded below its 50-day moving average, its first major breach in more than six months. The average has served as a floor of sorts for the index this year. Analysts say a breach of the index"s 200-day moving average is now in sight. Advancing issues outnumbered declining ones on the NYSE by a 1.66-to-1 ratio; on Nasdaq, a 1.69-to-1 ratio favored advancers. The S&P 500 posted no new 52-week highs and six new lows; the Nasdaq Composite recorded 38 new highs and 90 new lows.