A team of technicians from INTA Concepción del Uruguay, focused on expanding the onion producing regions in Argentina, obtained two onion varieties adapted to areas with a daily 70% relative humidity per year. The varieties are the Piré Hata INTA and the Mbareté INTA, both with good yields and a tolerance to fungal diseases such as the botrytis main and the downy mildew.
Juan Valiente, a specialist in crops from the INTA and a breeder of new varieties, said the main problem of the traditional onion cultivars is that they were obtained in regions of very low annual daily relative humidity, such as Mendoza, San Juan, Catamarca and La Rioja.
"We’ve been working on the evaluation of domestic and foreign varieties and hybrids for over 20 years to get the ideal cultivar for our region," said Valiente. He then added that "these varieties seek to be alternatives for the smallholder areas with a high relative humidity, such as Entre Rios, Corrientes, Chaco, Misiones and much of Santa Fe."
Hata Piré INTA (hard skin, in Guarani) is a short cycle variety, as 5 to 6 months pass from planting to harvest. It is an early onion grown in late February and harvested in October. It has a 12.5% dry matter and a good preservation after harvest.
Regarding physical characteristics, "Hata Piré INTA has a wide elliptical bulb, is firm, has a violet coloured pulp and its cataphylls – the leaves covering it- are red," said Valiente. "Since the short-cycle cultivars are all low pungency, this onion variety has an average level of 5.43 micromoles pirubic acid per gram, which makes it an ideal variety for the fresh market."
Valiente stated that the Mbareté INTA (strong, in Guarani) is similar to the Piré Hata: it’s cycle is short, its bulb is elliptical, firm, and it has a medium pungency. He also noted that "the main difference between the varieties is that the colour of the Mbaraté’s pulp is creamy white and its cataphylls are yellowish- brown."
According to Valiente, both varieties’ leaves are physically strong and don’t fall to the sides, "this is important because the leaves won’t get wet when it rains and the fungi that produce diseases such as botrytis and downy mildew can’t survive. So these varieties are very resistant."
Regarding income, Valiente said both varieties had potential when the campaign recorded a 70% daily relative humidity. "According to our field measurements, we had an average yield of 20,000 kilos per hectare by transplantation and, through direct seeding, the yields doubled and amounted to 40 tons per hectare."
Both cultivars were recently registered in the National Registry of Cultivar Property of the National Seed Institute.
Source: www.on24.com.ar