India's opposition parties not much of a threat to Gandhi's government

India's splintered noncommunist opposition parties are trying - without much success - to mount a new challenge to Prime Minister Indira Gandhi.

Split into quarreling factions since their unsuccessful experiment with coalition government from 1977 to '79, the parties have no hope of toppling the Gandhi government now.

But Mrs. Gandhi's ruling Congress-I Party, returned to power with commanding parliamentary majorities in 1980, appears to be taking the challenge seriously. The opposition's stabs at unity have drawn sharp attacks from the prime minister.

Although Mrs. Gandhi's popularity remains high, public opinion polls indicate broad dissatisfaction with conditions in the country. Scandals over official corruption and atrocities against ''untouchables'' have focused unflattering attention on weak Congress-I administrations in several states.

Now, with several states headed to the polls this year, the opposition is looking for fresh opportunities to increase its strength in key state legislatures.

The question is: can it overcome the personal and political rivalries that ruined the coalition Janata government in 1979 and have dogged unity efforts since?

Ideology rules out serious unity attempts with the two leading Indian communist parties. The noncommunist parties are exploring other options such as merging small splinter groups, supporting joint candidates in elections, and taking common stands against the government in Parliament.

During the past few months, there has been a flurry of merger talks - and an equal flurry of backpedaling - by three of the opposition parties: Lok Dal, Janata, and Congress-S. Political ovservers say chances for a successful merger are slim because the party chiefs all want to lead a coalition party.

The right-of-center Janata Party, led by Atal Bihari Vajpayee, who was India's foreign minister under the Janata coalition government, is perhaps the strongest of the noncommunist opposition parties. Saying it wishes to maintain its identity, it has opted out of merger talks.

''Its concern is to present itself as a national alternative, and that would become blurred if it blended in with the other parties,'' says a political analyst.

Nevertheless, the Janata Party has shown interest in what opposition parties call ''electoral adjustment'' - backing common candidates in vulnerable districts. It has also joined hands with parliamentary opposition parties to oppose the government on selected domestic and foreign policy issues.

This so-called ''functional unity'' forced the government to take a defensive posture onel4ufquoteWhile the government may be forced to defend itself, it is not in danger of defeat.

el4such issues as official corruption, attacks on untouchables by caste Hindus, relations with Pakistan, and the conditions attached to India's record loan from the International Monetary Fund.

In the recently opened spring session of Parliament, opposition parties are likely to focus their attack on Mrs. Gandhi's budget for the coming fiscal year.

While the government may be forced to defend itself, it is not in danger of defeat, since it holds a two-thirds majority in the lower house of Parliament.

But the government has stepped up its increasingly strident defense. Concerned about the coming challenge in the state assembly elections, Mrs. Gandhi points to the failure of the Janata coalition government and ridicules the current opposition moves. She says the parties have no common program other than to bring her government down.