Argentina's Army and its choice as president, retired Gen. Raynaldo Bignone, struggled today to consolidate power following the collapse of the country's joint military government but seemed to have little success in ending the power struggles and political paralysis provoked by Argentina's loss on the Falkland Islands.

Military chiefs and services issued contradictory accounts of the Army's full assumption of power last night, and it remained unclear late today whether the new Army government would win the cooperation of the Argentine Navy and Air Force, the country's civilian political leaders and even its own internal ranks.

The Army reportedly lacks support in large part because of traditional rivalries among the services and opposition to its conservative positions against a quick return to civilian rule and in favor of current anti-inflationary economic policies.

Bignone met today with both Navy commander Jorge Anaya and Air Force chief Basilio Lami Dozo to seek at least tacit backing for the Army, which announced last night that it would govern the country without the participation of the other two services during a "limited transition" to democratic rule. But Lami Dozo and Anaya, who had strongly opposed Bignone's appointment, made no move to moderate communiques issued by their headquarters last night that explicitly cited their differences with the Army's presidential plan as their reasons for withdrawing from the six-year-old military government.

In addition, sources here said that Bignone and new Army commander Lt. Gen. Cristino Nicolaides could face internal dissension from Army officers of the second and third ranks who are unhappy with the new leadership and convinced that a clean sweep should be made of military commanders associated with the Falklands invasion.

Tonight, a large meeting of Army generals was convened to discuss the new political situation and the viability of the Army's prospective government.

Military and political sources said today that the Air Force and Navy leaders have withdrawn from the government in part because of their inability to block the dominant Army in its move to name Bignone to replace Gen. Leopoldo Galtieri, who was ousted from his post as president and Army commander in chief last Thursday.

The two dissident services, whose military power does not approach that of the Army, are also seeking to avoid pressure from Army commanders for the resignations of both Anaya and Lami Dozo, who along with Galtieri launched the Falklands invasion April 2 and failed to reach a diplomatic settlement with Britain before the military conflict was lost.

At stake in the power struggle, military sources said, was both the assignment of responsibility within the armed forces for the failed operation in the Falklands and the traditional pecking order among military chiefs, many of whom are motivated by rivalries and obscure causes dating back through generations of military infighting.

One high Navy official indicated today in an interview that the Navy was also seeking to avoid responsibility for any Argentine agreement to a cease-fire with Britain in the South Atlantic. Acceptance of a cease-fire is considered inevitable by many military leaders, but it is regarded as a difficult action to explain within Argentina.

Navy and Air Force officials have also sought to portray the split as caused by the Army's intention to continue with social and political policies unacceptable to the other forces. These officials maintained today that the new Army leadership might seek to prolong itself in power despite its pledge to "institutionalize" the country in early 1984, when Galtieri's term was scheduled to expire.

Bignone and Nicolaides were also described as favoring the conservative, anti-inflationary and free market oriented economic policies that have been a chief complaint of the military's civilian opponents. Air Force and Navy leaders have favored reversing those policies in favor of a government-managed effort to jolt Argentina out of a severe recession.

Army leaders made no effort to clarify their position on elections and economic policy today, and civilian leaders, reacting to the unofficial reports circulating in Buenos Aires, did not immediately agree to meet Bignone.

Bignone told reporters this morning that his "first priority" was to meet with political party leaders to explain his government plan and that he hoped to arrange the meeting today. Political leaders avoided responding to the invitation, however, and the country's five largest political parties were expected to hold a meeting of their joint organization this evening to discuss how to respond to the Army takeover.

Political sources said today that the civilian leadership has been hesitant to associate itself with a government that did not have the support of the full armed forces, believing that such a move would compromise them in an ongoing military power struggle that they have so far carefully avoided.

In addition, many political leaders are believed to be disturbed by the Army's more conservative position within the military and by the reputations of Nicolaides and Bignone.

Nicolaides, who as commander in chief could emerge as the strongest figure in the new government, is regarded by many Argentine politicians as a political extremist who has little respect for democratic government or Argentina's traditional popular movements. He has feuded openly with moderate political leaders and once said that the world has been threatened by Marxism since 500 years before the birth of Christ.

Bignone, a 56-year-old former Army general secretary, has a reputation for relative political moderation within the Army but has strong ties with Nicolaides and several other right-wing generals.