DirecTV Group Inc. said Thursday that its net income in the second quarter increased 29 percent as its subscriber base grew, especially in Latin America. But the company added far fewer subscribers in the U.S. than it has in previous quarters — 26,000 compared with 100,000 in the same period a year ago. Its shares fell 3 percent in premarket trading.The nation’s second-biggest provider of pay-TV services said Thursday that its net income rose to $701 million, or 91 cents per share. That’s up from $543 million, or 42 cents per share, a year earlier. Its revenue grew 13 percent to $6.6 billion from $5.85 billion. Analysts had expected earnings of 85 cents per share on revenue of $6.55 billion, according to FactSet. The company added 472,000 net subscribers in Latin America during the quarter, ending the period with 6.7 million. The demand was mainly from Brazil. In the U.S., its main source of revenue, it ended the quarter with 19.4 million subscribers.