Effect of environmental factors on biological characters and grain quality of vietnamese foxtail millet (Setaria italica L.)

Foxtail millet(CM), a plant with high nutrient and higher heavy metal in grain, is sustainable under drought conditions. Using millet grain to produce food nutrient for human is necessary. In this study, collected foxtail millet germplasm and selected variety with high grain yield and grain quality in each ecological region as well as build-up cultivation technique in Vietnam. Total of 11 varieties of foxtail millet collected in Vietnam were described and distinguished their botanical characters. Among them, 4 varieties (CCM1, CM9, CM10 and CM11) were selected to estimate the correlations among photosynthetic rate, stomatal conductance, transpiration rate and dry matter accumulation under irrigated, drought and recovering condition in a pot experiment. A field experiment was conducted to estimate the affection of three ecological regions such as Gialam (Red River Delta with an altitude of 5-20 meters), Bacha (Northern mountainous region with an altitude of 600-1000 meters) and Sapa (Northern mountainous region with an altitude of 1500-1800 meters) on several agronomic characters viz., growth duration, dry matter accumulation, grain yield and grain quality in four varieties. The average growth duration of all millet varieties were longer in Sapa (136 days) than in Bacha (130 days) and Gialam (108 days). The average grain yield of all millet varieties was highest in Sapa (2.7 ton/ha) than in Bacha (2.0 ton/ha) and Gialam (1.1 ton/ha), contributed to both the larger number of spikelets per panicle and the higher 1000-grain weight. The highest grain yield was observed in CM1 in Gialam, whereas it was found in CM9 in Bacha and Sapa. This was due the different varietal response to temperature, water supply and/or radiation. It was found that ecological regions affected protein, lipid and amylose content in millet grain. Another field experiment was conducted to study the effect of nitrogen (N) fertilizer on grain yield and grain quality of two foxtail millet varieties (CM1 and CM9) in Gialam. As application four levels of N fertilizer (O,30,45 and 60 Kg N per ha), grain yield was the highest in CM1 at 60 Kg N level (2.78 ton per ha), but highest in CM9 at 45 N level (3.02 ton per ha). This was due to the higher chlorophyll content at vegetative growth stage and dry matter accumulation at heading stage. However at high N fertilizer the grain quality decreased. Further technology would be studied on using millet grain for commercial food nutrient product.