Abstract:

This paper mainly focused on how different spacing forms affected the population canopy structure of winter wheat with different spike types in Jinzhong late maturing winter wheat zone. Under field condition, chose two varieties with different spike shapes for research. With the same seeding amount, adopted spacing forms of 10 cm and 20 cm respectively, and studied the differences of population leaf area index (LAI), mean leaf inclination angle (MLIA), transmission coefficient for radiation penetration (TCRP), extinction coefficient (K) as well as yield. The results showed that the 10cm spacing form could increase the overall leaf area index (LAI) in whole growth stage, the K in middle stage of grouting, yield, and decreased the MLIA in flowering stage and filling stage of two wheat varieties in comparison with 20cm. The total LAI in whole growth stage of multi-spiked variety was higher than that of large-spiked variety. The MLIA of two growing stages with 10 cm (B3) spacing form was: A1>A2. The TCRP of four treatments diminished gradually with raising the zenith angle. The average and range of TCRP of 10cm spacing form were lower than that of 20cm spacing form and two averages had much difference of large-spiked variety. The average and range of TCRP of 10cm spacing form were higher than that of 20cm spacing form and two averages did not have much difference of multi-spiked variety. The yield increase rate indicated that 10cm spacing form had more obvious effect on the yield increase of multi-spiked wheat variety. B3 spacing form could optimize wheat population canopy structure in Jinzhong late maturing winter wheat zone and was suitable to northern late maturing winter wheat zone.