长期不同施肥处理对连作高粱生长规律及产量的影响研究

以甜高粱品种‘新高粱3号’为试验材料,采用长期定位施肥方式,研究CK、NK、NP、PK、NPK、M(有机肥)、NPKM、1.5NPKM 8个不同施肥处理对甜高粱生长规律、含糖锤度、叶绿素含量及产量的影响,筛选出适宜新疆干旱区连作甜高粱生长的最佳施肥方式。结果显示,不同施肥处理对连作甜高粱的生育期、农艺性状、叶绿素含量、秸秆含糖锤度及产量均有影响。在不同施肥处理下甜高粱的株高、茎粗、叶片数、秸秆含糖锤度和叶绿素含量在整个生育阶段的变化趋势基本一致,但不同施肥处理之间有差异。成熟期不同施肥处理之间的株高、茎粗和茎秆含糖锤度差异较大、叶片数差异不大,其中NPKM施肥处理的株高、茎粗和含糖锤度分别为224.33 cm、21.47 mm、18.41%,均高于其他施肥处理,并比CK极显著增高了13.86%、39.60%、23.47%。施肥有利于秸秆含糖锤度的积累,在抽穗后第28天时达到最高值,此时,NPKM处理达到18.57%,但抽穗期到成熟期不同茎节含糖锤度在不同施肥处理下的积累规律不一致。各处理的叶绿素含量在整个生育期的变化趋势基本一致,灌浆期时达到最大值,其中NPKM处理叶绿素达到44.62 SPAD。所有施肥处理的秸秆产量、籽粒产量和生物产量均比CK极显著地增加,其中NPKM处理秸秆产量、籽粒产量、生物产量分别达到90.80、4.01、94.81 t·hm^-2,均高于其他处理。施肥有利于增加甜高粱的产量、含糖锤度及经济效益,利用不同施肥方式来缓解高粱连作障碍的过程中应当注重采取不同的肥料配比。综合来看,有机肥、无机肥混合施用(NPKM)是促进干旱区连作高粱生长发育的最佳施肥模式。

Effects of fertilization on growth and yield of continuously cropped sweet sorghum

This research explored the effect of a range of different fertilizer regimes on crop performance of the sweet sorghum variety ‘Xin Gaoliang No.3’ under long-term continuous cropping in the arid region of Xinjiang Province. The experiment comprised eight fertilizer treatments designated CK (control), NK, NP, PK, NPK, M (organic manure fertilizer), NPKM and 1.5NPKM. The traits monitored for ‘Xin Gaoliang No.3’ included plant height, stem diameter, leaf number, brix sugar level, chlorophyll content and yield, among others. The different fertilizer treatments significantly affected a majority of agronomic traits. In general, trends in the different measures (plant height, stem diameter, leaf number, sugar brix content and chlorophyll content) were basically the same for any given fertilizer treatment as the crop developed, but there were differences between the different treatments. At crop maturity, the plant height, stem diameter and brix sugar content were 224.33 cm, 21.47 mm and 18.41%, respectively, for the NPKM fertilizer treatment and these values were significantly higher than those of all other treatments and, respectively, 13.86%, 39.60% and 23.47% greater than in the CK treatment. Fertilization enhanced brix sugar levels in the stem. The stem brix sugar value peaked (18.57%) on the 28th day after mean heading date. but the accumulation patterns brix sugar at different stem nodes from the heading to the maturity differed between fertilization treatments. The pattern of change in chlorophyll content with crop development was basically a constant gradual increase, which peaked at 44.62 SPAD units for the NPKM treatment. The straw yield, grain yield and biomass yield for all fertilizer treatments were significantly higher than those for CK. The straw yield, grain yield and biomass values for the NPKM treatment were 90.80, 4.01 and 94.81 t·ha^-1, respectively, and were the highest among all the treatments. Fertilizer application is beneficial to increase the yield, brix sugar and economic benefit of sweet sorghum. To improve the sustainability of a continuous sweet sorghum cropping system, the choice of fertilizer should be considered. In general, mixed application of organic and inorganic fertilizers (NPKM) is the best fertilizer regime to enhance sustainability of continuous sweet sorghum cropping system in the arid regions of Xinjiang Province.