外源赤霉素对不同磷素水平下胡麻产量形成的调控效应研究

为探究磷素养分和外源赤霉素(GA3)对旱地胡麻干物质积累特征及产量形成的调控效应,采用田间二因素裂区试验设计,研究了不同磷素水平(0、67.5和135 kg P2O5·hm-2)下于现蕾期和盛花期不喷和喷施15 mg·L-1、30 mg·L-1 GA3对胡麻干物质积累规律,花前、花后转运特征及产量的影响.结果表明:磷素...

Effects of exogenous gibberellic acid on yield formation of flax under different phosphorus levels

A field experiment with two-factor split-plot design was conducted to realize the effects of phosphorus and exogenous gibberellic acid on dry matter accumulation and yield formation of dry-land flax. We studied the effects of different phosphorus levels （0 kg P₂O₅·hm^-2, 67.5 kg P₂O₅·hm^-2 and 135 kg P₂O₅·hm^-2） with and without spraying 15 mg·L^-1 and 30 mg·L^-1 GA₃ at the budding and anthesis stages on the dry matter accumulation and transportation at pre-anthesis and post-anthesis, and the yield formation of flax. Results showed that both phosphorus and GA₃ significantly promoted the yield formation of flax, and had a positive interaction effect between them. The contribution of phosphorus to the seed yield of oilseed flax was greater than that of GA₃. Phosphorus application alone significantly increased the 1000-grain weight and fruit number of flax. Spraying GA₃ had a significant effect on the effective capsule number and 1000-grain weight, and the interaction between phosphorus and GA₃ significantly increased the seed yield of flax. Dry matter accumulation and yield of flax increased with the increasing GA₃ concentration at 0 and 67.5 kg P₂O₅·hm^-2. Spraying 15 mg·L^-1 GA₃ at the phosphorus level of 135 kg P₂O₅·hm^-2 had the highest average dry matter growth rate, which was significantly increased by 55.51% compared with the treatment without fertilizer and hormone. The dry matter accumulation after anthesis and its contribution to grains was increased by 58.69% and 139.32% （2019）, 52.23% and 25.10% （2020）, respectively. The dry matter accumulation and yield reached the maximum, which were significantly higher than the P₀G₀ treatment by 55.51% and 17.25% on average. Our results showed that the interaction of phosphate and exogenous hormones promoted the dry matter accumulation and the contribution rate of seed at post-anthesis, increased the 1000-grain weight and fruit number, and then the grain yield of flax increased. It was determined that phosphorus application 109.35-111.26 kg·hm^-2 combined with 22.37-23.08 mg·L^-1 GA₃ spraying might be a suitable high-yield cultivation technique in dry farming areas.