Rio Balsas Maize, 6700 BC. New data pushes back maize earlier in Mexico than outside mexico and in the right part of Mexico, but notice that it is already domesticated, which means the beginnings of cultivation are earlier. This has a ScienceNOW post by Michael Balter, and the artilce by Piperno et al in PNAS (March 2009), "Starch grain and phytolith evidence for early ninth millennium B.P. maize from the Central Balsas River Valley, Mexico," needs to be read with the Ranere et al PNAS paper in the volume on the archaeological context., "The cultural and chronological context of early Holocene maize and squash domestication in the Central Balsas River Valley, Mexico".
North Peruvian Early Agriculture. Starch grain data from human teeth confirms the consumption og Phaseolus beans, squach (Cucurbita cf. moschata) and peanut at ca. 6000 BC, as reported in the recent (Dec 2008) PNAS paper by Piperno and Dillehay. The confirms the evidence of macrobotanical remains reported by Dillehay et al in 2007 in Science, in which AMS dates pushed cultivation in this region back to 7000-8000 BC. While all this may be suggestive of this area being an early focus of agriculture (and it featured as possible centre 3c in the recent Purugganan and Fuller map in a Nature review), some of this crops (certainly peanut) and arguably squash (?) were probably not native this particular region, implying that their start to cultivation was somewhere else and even earlier!
North American Early Crops. The latest installment on the evidence for indigenous domesticates of the later Mid-Holocene of Eastern North America is represented by the Smith and Yarnell report on the Riverton seed assemblage in PNAS 7 April 2009, which includes some of the classic 'lost crops' of North America such as Hordeum pusillium and Chenopodium berlanderi