Publication Date:
1988-06-01
Description:
SummaryThe intercropping of Azolla pinnata (Vietnam) with rice varieties transplanted in rectangular (40×10 cm) and double-narrow-row (15 × 10:65–80 cm) spacings showed faster growth and nitrogen fixation than in square (20 × 20 cm) spacing with the same number of hills per unit area. Inoculation of 2·0 t/ha fresh Azolla, 10 and 30 days after transplanting, produced Azolla mats on the water surface 25 and 50 days after transplanting, respectively. The total fresh biomass of Azolla grown with different rice varieties in square spacing was 26·7–33·0 t/ha; this produced 41·9–61·3 kg N/ha. However, rectangular and double-narrow-row spacing produced 28·7–37·7 and 34·4–39·6 t/ha fresh Azolla containing 53·9–69·0 and 58·0·73–3 kg N/ha, respectively if the rice rows were transplanted in north-south direction and 36·3–41·5 and 40·0–43·7 t/ha fresh biomass containing 63·4–74·2 and 65·3–83·3 kg N/ha, respectively in east-west direction.The grain and straw yields of rice grown in rectangular and double-narrow-row spacing with north-south row orientation were lower than the yields of rice in square spacing, but the east-west row orientation of these spacings showed yields similar to those obtained by growing rice in square spacing.
Print ISSN:
0021-8596
Electronic ISSN:
1469-5146
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
