New soybean cultivar from the EEAOC: Munasqa RR

DEVANI, M; LEDESMA, F; LENIS, J; GANDUR, M; PLOPER, L.D.

Foz do Iguassú

Conferencia; VII World Soybean Research Conference (VII WSRC).; 2004

Embrapa SOJA y WSRC Continuing Committee

The use of glyphosate-resistant varieties in northwestern Argentina (NWA) has experienced a remarkable increment in recent years.  Currently, over 95% of the soybean area in this region is occupied by these transgenic varieties.  Main reasons for the rapid adoption of this technology were reduction in production costs, improved weed management, and high yield potential of many of these materials.  Considering this new scenario, the Estación Experimental Agroindustrial Obispo Colombres (EEAOC) developed Munasqa RR, a new soybean cultivar resistant to glyphosate, which adds another option to the current offer of long cycle materials for NWA.  In addition to resistance to the main diseases of the region, Munasqa RR has shown great adaptation, stability, and high yield potential throughout NWA.  Munasqa RR was obtained from a cross between the varieties A 6401 RG and FAM 841 performed during the 1996/97 season at the Monte Redondo Substation, located in San Agustín, Department Cruz Alta, Tucumán.  This new variety has a determinate stem and is classified as Maturity Group VIII, with 52 and 125 days from planting to flowering and physiological maturity, respectively.  It has white flowers, grey pubescence, very good plant structure, and resistance to lodging and shattering.  Seeds are spherical, yellow, with clear brown hila.  Mean weight of 1000 seeds is 141.8 g, and the reaction for the peroxidase test is negative.  Seed quality tends to be good to very good, with average 21.35% oil and 39.52% protein.  In addition to high and stable yields, Munasqa RR has shown good plasticity, allowing a wide range of planting dates, from 15 November to 15 January, with the optimum during the second and third decades of December. After two consecutive years of Yield Comparative Trials at San Agustín, La Cruz, and La Cocha, Munasqa RR averaged 3909 kg/ha, while the control cultivars Coker 6738, A 6401 RG, and A 7986 were 11%, 10%, and 5%, respectively, lower than the new cultivar.