BUENOS AIRES, March 7 (Reuters) - Argentine biotech firm Bioceres Crop Solutions Corp will market its drought-tolerant genetically modified wheat in Argentina this year, its chief executive said, after a key Brazil approval and dry weather bolstered the case for GMO.

Bioceres is leading the push globally to establish GMO wheat and break a taboo over transgenic wheat going back decades due to consumer fears that allergens or toxicities could emerge in a staple used worldwide for bread, pasta and pastries.

Those fears are now starting to ease as high food prices, the war in Ukraine and more regular droughts hitting crop harvests shift the needle for farmers and flour millers.

In an interview on Tuesday, Bioceres CEO Federico Trucco told Reuters the firm would start to market HB4 wheat this year, though it would focus on working with seed "multipliers," dedicated to increasing seed numbers versus turning the grain to flour.

"In the first year it will probably only be the multipliers able to scale it, but there may be some bags for producers who want to test the technology," said Trucco.

The plans come after Brazil approved HB4 wheat for planting last week, and after early trials in Argentina, which has been battered by drought since last year, showed HB4 yields outperforming regular wheat by as much as 43% in dry conditions.

Trucco said the trials used "twin" wheat strains, "identical in all genes except the presence or absence of HB4."

"We made comparisons between twins in 20 different places in Argentina and the difference was undisputable because there is not a single case where the twin that has HB4 performed less well than the one that does not," he said.

Bioceres, however, faces a long road ahead, despite approvals and improving acceptance by potential buyers. Brazil, a major food producer, is the largest buyer of Argentine wheat.

The giant South American country is planning to expand testing of HB4 wheat, though it will take four years to test the seed's adaptability to tropical conditions and it needs more seeds to be able to do large-scale testing.

Trucco said for the 2023/24 season, which starts in May, the firm would work with seed multipliers who could then offer seeds to their own producers. Until now, Bioceres produced HB4 wheat only through direct private deals with farmers.

In Brazil he said HB4 wheat could help eventually expand the wheat planting area by around 50% by making wheat more drought- tolerant. Brazil plants some 3 million hectares with wheat, mostly in southern states like Rio Grande do Sul and Parana.

Beyond Brazil, HB4 wheat has gained approvals for consumption in Australia and New Zealand, as well as Nigeria, where the entry of the GMO grain is allowed.

Bioceres is also keen to make progress in the United States, where it has received a green light from the Food and Drug Administration, but is waiting for approval from the U.S. Department of Agriculture, Trucco said.

"We have had a very active dialogue with the U.S. wheat associations," said Trucco. "We are working with some American universities that have the germplasm for the area of interest to us, which is mainly the Great Plains." (Reporting by Maximilian Heath in Buenos Aires Editing by Adam Jourdan and Matthew Lewis)