Abstract:
【Objective】 To further explore the response law of winter, wheat growth in northern Xinjiang to super late sowing and solve the problems of late crop rotation and low water-saving efficiency in local agricultural production.
【Methods】 Using a randomized block design, five ultra-late sowing dates (D
1, D
2, D
3, D
4, D
5) were set up, and the effects of different sowing dates on the photosynthetic characteristics, dry matter accumulation and yield of wheat were analyzed with the local suitable sowing date as the control (CK).
【Results】 Compared with CK, the average emergence rate of ultra-late sowing wheat decreased by 57.22%, the flowering stage was 8.2 d later, the maturity stage was 6 d later, and the filling time was 2.2 d shorter.There was no significant difference in the emergence rate of ultra-late sowing wheat among different treatments, the highest was D
1, and D
1 entered the flowering and maturity stage the earliest, and the filling time was the longest; The average
SPAD value of flag leaf decreased from 0-14 days after anthesis, but increased from 21-28 days after anthesis, and the average
Pn increased by 1.92% at filling stage.The
SPAD value of flag leaf D
3 was the highest and D
1 was the lowest at 0-28 days after anthesis, but
Pn D
1 was the highest at filling stage, increased by 11.25% compared with D
3; The dry matter accumulation of single plant in tillering stage to jointing stage decreased, the dry matter distribution rate of vegetative organs in mature stage decreased, and the dry matter distribution rate of grain increased.The dry matter accumulation of single plant and the dry matter distribution rate of grain D
3 in booting stage to mature stage of ultra-late sowing wheat were the highest; the average spike number and yield decreased by 19.33% and 5.55% respectively, and the average spike number and 1,000-grain weight increased by 7.87% and 4.64% respectively.The spike number, 1,000-grain weight and yield D
1 of ultra-late sowing wheat were the highest, increased by 19.21%, 2.85% and 20.88% respectively compared with D
3, and the spike number D
3 was the highest, decreased by 4.47% compared with D
1.
【Conclusion】 The ultra-late sowing wheat in northern Xinjiang should be sown when there is no snow or frozen soil in the field from late October to early November, and there is no obvious snowfall in the near future after sowing.