Effects of Planting Density and Fertilization Level on Agronomic Traits and Grain Starch Characteristics of Malting Barley

Purpose To study the effects of planting density and fertilization level on agronomic traits and grain starch characteristics of malting barley.

Methods The malting barley variety ‘Yunpi 511’ was used as material, three planting densities: low (900000 plants/hm²), medium (1125000 plants/hm²) and high (1350000 plants/hm²), and six fertilization levels: F₀ (no fertilization), F₁ (applying compound fertilizer 180 kg/hm²), F₂ (applying urea 180 kg/hm²), F₃ (applying urea 45 kg/hm²+compound fertilizer 135 kg/hm²), F₄ (applying urea 90 kg/hm²+compound fertilizer 90 kg/hm²), and F₅ (applying urea 135 kg/hm²+compound fertilizer 45 kg/hm²), were set. The main agronomic traits as well as soluble sugar and grain starch contents of each organ after flowering were determined by a two-factor randomized group trial with planting density and fertilization level, and correlation analyses of soluble sugar content and grain starch content were carried out.

Results Under the same fertilization level, the yield of malting barley planted at medium density was significantly higher than that of other density treatments, and the tillers number of barley planted at low density was generally higher than that at medium and high density treatments. Under the same planting density treatment, F₄ treatment was more conducive to the accumulation of soluble sugar in various organs during the active period of post-anthesis filling, and its final grain starch content was higher than that of other fertilization treatments.

Conclusion Yunpi 511 can meet the growth requirements under the conditions of planting density of 1125000 plants/hm² and fertilization of urea 90 kg/hm²+compound fertilizer 90 kg/hm². The results of the study can provide theoretical basis for the green and efficient cultivation of barley.