Most rice-growing areas in Assam, India, are monocropped. Farmers grow longduration varieties (140-160 d) in areas where land becomes unsuitable to take up rabi (wet season) crops because of moisture stress and cold environmental conditions after rice harvest. This is why most cultivable land remains fallow after sali (June/July-November/December) rice. Rice cultivars with medium duration (130 d) are needed to grow rabi crops after fallow and thus increase cropping intensity.