钾肥用量对不同品种旱地胡麻抗倒伏能力及产量的影响

为探索钾肥调节胡麻抗倒伏特性的机理,在大田环境下,以2个当地主栽胡麻品种‘陇亚11号’(V1)和‘定亚23号’(V2)为供试材料,设置不施钾(K0, 0 kg/hm²)、低钾(K1, 30 kg/hm²)、中钾(K2, 60 kg/hm²)与高钾(K3, 90 kg/hm²)4个施钾水平的裂区试验,分析了不同品种和钾肥施量组合对旱地胡麻株高、重心高度、茎粗、抗折力、抗倒伏指数、实际倒伏率和产量与产量构成的影响及其与植株抗倒伏特性的关系。结果表明:在0~90 kg/hm²钾肥施量范围内,增施钾肥在促进胡麻生长发育的同时亦可提高胡麻抗倒伏性能,最终提高产量。施钾后,2品种胡麻株高和重心高度在全生育期较不施钾(K0)平均分别提高了4.74%和8.88%。茎粗值（青果期）在施钾60 kg/hm²(K2)时最大,较不施钾(K0)平均增加11.79%。施钾较不施钾(K0)茎秆抗折力和抗倒伏指数平均高出18.32%和11.50%。不同施钾水平下胡麻实际倒伏率表现为:K2K3>K1>K0,较不施钾增产率依次分别为20.69%、24.93%和17.15%;相关分析表明:胡麻株高和重心高度与茎秆抗折力无显著相关性,与抗倒伏指数呈显著、极显著负相关（除成熟期外）;各生育时期胡麻茎秆抗折力和抗倒伏指数与茎粗均呈正相关,与籽粒产量呈显著、极显著正相关关系。综合分析,在本试验条件下60 kg/hm²作为适宜钾肥施用量,在兼顾增产的同时亦能有效增强胡麻抗倒伏能力。

Effects of Potassium Fertilizer Application Rate on Lodging Resistance and Yield of Oil Flax Varieties in Dry Land

To explore the mechanism of potassium fertilizer regulating the lodging resistance of oil flax, in field environment, two local oil flax varieties ‘Longya 11’ (V1) and ‘Dingya 23’ (V2) were used as test materials, and the split plot experiment was conducted with four potassium application levels: no potassium (K0, 0 kg/hm ²), low potassium (K1, 30 kg/hm²), medium potassium (K2, 60 kg/hm²) and high potassium (K3, 90 kg/hm²). The effects of different varieties and potassium fertilizer combinations on the plant height, center of gravity height, stem diameter, flexural resistance, lodging resistance index, actual lodging rate, yield and yield components of dry land oil flax and their relationship with plant lodging resistance characteristics were analyzed. The results showed that, the potassium fertilizer application rate of 0~90 kg/hm² could not only promote the growth and development of oil flax, but also improve its lodging resistance, and ultimately increase its yield. After potassium application, the plant height and center of gravity height of the two varieties of oil flax were increased by 4.74% and 8.88% respectively during the whole growth period compared with no potassium application (K0). The stem diameter (green fruit stage) was the largest when the potassium application rate was 60 kg/hm² (K2), increased by 11.79% on average compared with no potassium (K0). The flexural resistance and lodging resistance index of oil flax stalks after applying potassium were 18.32% and 11.50% higher than those without potassium (K0). The actual lodging rate of oil flax under different potassium application levels was: K2K3>K1>K0, and the yield increase rate were 20.69%, 24.93%, and 17.15%, respectively. Correlation analysis showed that the plant height of oil flax and center of gravity height had no significant correlation with the stalk bending resistance, but had a significant and an extremely significant negative correlation with the lodging resistance index (except for the mature period); the flexural resistance and lodging resistance index of oil flax stalks in each growth period were positively correlated with stem diameter, and had a significant and an extremely significant positive correlation with grain yield. In general, under the experimental condition of the study, 60 kg/hm² is the appropriate potassium fertilizer application rate, which could not only increase the yield, but also effectively enhance the lodging resistance of oil flax.