Led by a strong export performance, notably for manufactured goods, the world's poorer countries maintained near-record economic growth rates last year, according to the annual report of the International Finance Corporation published yesterday.

The IFC is an affiliate of the World Bank specializing in aiding the private sector of the developing nations. The annual report said that the IFC had approved $8ll million in loans and equity commitments in 34 countries last year, for projects costing $3.3 billion.

Despite the favorable economic results over-all in the less-developed nations of the world, the IFC was quick to point out that the global numbers masked exceptionally serious problems in the poorest of the poor countries, especially those in Africa. And looking ahead, it said that there appears to be "a bleak landscape for development" because of the low-growth prospects in the industrial world and the escalation of energy costs.

Nonetheless, the achievement of many of the developing countries, based on a strategy of stressing exports, were impressive. For example, the IFC said that preliminary data indicate that the exports of the non-OPEC developing countries grew last year by 23 percent in dollar terms, or 7 percent in real terms.

"The principal contributor to developing country export performance in the l970s," the report said, "was the strength of their exports of manufactures. In constant dollar terms, these grew at almost 13 percent per year over the decade, more than three times faster on the average than their nonfuel primary exports."

Labor-intensive products such as clothing and textiles were the fastest-growing manufactured products, even though those are the areas where industrial nations have applied the most severe protectionist restrictions. On the whole, however, the report said that new protectionist quotas generally had affected "the strongest and most resilient developing economies", many of whom were able to diversify or to relocate their export production to less affected developing countries.

Looking ahead to development problems in this decade, the IFC said that "new approaches are called for, and the foundations for them are in some cases already evident." It urged the less-developed nations to "mobilize additional equity" of their own, and to solicit more private direct investment.

"Even in sectors and industries where foreign ownership is not acceptable to developing countries," the IFC said, "it may be possible to encourage foreign capital flows which involve elements of risk-sharing, and, thus, do not have fixed debt-service requirements." It also mentioned the possibility of production-sharing arrangements.

As for the poorest developing countries, the IFC said they face "a staggering set of constraints" and will require all of the concessional capital that appears to be available -- and more -- as well as a greater effort of their own "to lift themselves from the grinding poverty they now face."

The IFC pledged to make a maximum effort to help these poor nations, noting that about half of the ventures it supported in 1980 were in low-income countries. Geographically, about 25 percent were in Africa, 25 percent in Asia, 40 percent in Latin America, and the balance in Europe and the Middle East.