Thailand is the major producer of high-quality aromatic Jasmine
rice, which commands a premium price in the world market
[1,2]. Jasmine rice is mostly grown under rainfed conditions in the
north-east of the country, a region characterized by an undulating
landscape with generally poor soils and erratic rainfall [3]. The
crop is grown in the rainy season, which lasts from June to November.
To avoid the drought period after November, farmers grow
photoperiod-sensitive varieties, such as Jasmine variety KDML105,
that flower around October and are harvested by November.
Farmers grow their crops in bunded fields on gentle slopes (toposequences)
that are characterized by a high degree of heterogeneity
in hydrology and chemical and physical soil conditions. On top o