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In this study, the effects of nitrogen (N) rate (60, 120, 180 and 240 kg N ha?1 applied in three equal dressings at seeding and after the first and second cuttings) and stubble height (7, 14 and 21 cm) on the dry matter (DM) yield, crude protein (CP) content, and CP yield of a sorghum–sudangrass hybrid [Sorghum bicolor (L.) Moench × Sorghum sudanense (Piper) Stapf., cv. Pioneer 988] in the three‐cut system was investigated. The N rate had no significant effect in the first and third cuttings, but in the second cutting DM yields increased significantly with increase in N rate. The highest yield of 9.1 t ha?1 was obtained with 80 kg N ha?1 for the average of 2 years at the second cutting, but no significant difference was found among the 40, 60 and 80 kg N ha?1 rates. CP content and yield were not significantly affected by N rate at the first and third cuttings, but CP content and yield were significantly affected by application of N at the second cutting. Stubble height had a significant effect on CP content at the third cutting. However, it had no significant effect on CP content at the first and second cuttings. Stubble height had a significant effect on the CP yield at the first cutting, but no significant effect on CP yield at the second and third cuttings. 相似文献
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Abstract. In Australia, stubble burning and tillage are two of the major processes responsible for the decline of soil organic carbon concentration in cropped soils, and the resulting soil degradation. However, the relative importance of these two practices in influencing the soil organic carbon concentration and the long-term impact on soil quality and productivity are not clear. The effects of stubble burning as practised by farmers in southeastern Australia were evaluated in two field trials, one of 19 years duration, the other of 5 years. Conventional tillage (three tillage passes) led to greater loss of soil organic carbon than stubble burning. Loss of total soil organic carbon attributed to stubble burning in the 0–10 cm layer was estimated to be 1.75 t C ha−1 over the period of the 19-year trial, equivalent to 29% of that lost due to tillage. In the 5-year trial, no change in soil organic carbon due to stubble burning was detectable. Changes in soil quality associated with stubble burning detected in the longer trial included a reduction in macro-aggregate stability, and increases in pH and exchangeable K+ . Only the latter two were detected in the shorter trial. A higher mean wheat yield (average 0.15 t ha−1 ) following stubble burning was observed in the 19-year trial but not in the 5-year trial. Research to monitor the longer term effects of stubble burning is needed, and to identify conditions where loss of soil organic carbon is minimized. 相似文献
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晚稻机收留高茬紫云英迟播技术的应用效果研究 总被引:2,自引:0,他引:2
通过田间试验,研究了双季稻田晚稻机械收获留高茬后紫云英迟播的应用效果。结果表明,与传统紫云英播种技术相比,晚稻机械收获留高茬紫云英迟播显著缩短了紫云英的生育期,但其盛花期能保持与传统播种技术一致,对下茬早稻作物的种植没有影响;两种播种方法对盛花期鲜草产量、植株养分含量和养分积累量均没有显著影响,说明迟播播种能达到与传统播种一样的肥田目的;迟播对紫云英的种子产量及产量构成因素均没有明显影响,与传统播种技术相比可节约劳动力成本约45元/hm2,且可避免传统播种方法对晚稻植株的伤害。在现代双季稻种植条件下,晚稻机械收获留高茬紫云英迟播技术具有较大的优势和发展前景。 相似文献
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国家专利产品4JQM-110型玉米秸秆切碎灭茬还田机,配套动力50-80马力拖拉机,后置双行作业,结构原理独特,利用卧式高速旋转刀,同时完成秸秆切碎和灭茬保墒复式作业,属国内独创.经省级农机专家鉴定,技术属国际领先.灭茬机构模仿人工用钣镢收获玉米秸秆的过程,把砍切刀设计成卧式高速旋转刀,使收获玉米秸秆的过程高速连续化,完成灭茬覆土保墒作业;秸秆切碎机构模仿人工用铡刀铡切玉米秸秆的过程把切刀设计成卧式高速旋转刀,使切碎秸秆过程高速连续化完成秸秆切碎作业. 相似文献
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合理的茎蘖组合是提升小麦绿色高效生产的重要因素。为了解湖北稻茬小麦主要茎蘖对产量及主要农艺性状的影响,以大穗型小麦品种川麦104和多穗型小麦品种扬麦15为材料,于2016-2018年在湖北十堰和武汉两地稻茬麦大田条件下,设置低(1.35×106~1.65×106株·hm^-2)、中(2.85×106~3.15×106株·hm^-2)、高(4.35×106~4.65×106株·hm^-2)三种种植密度,分析了主茎(S)、分蘖1(T1)、分蘖2(T2)和分蘖3(T3)(按出现先后顺序)的成穗率、产量贡献率及相关农艺性状的表现。结果表明:(1)湖北稻茬小麦成穗茎蘖农艺性状表现值偏低,除穗长和茎高受品种的影响最大外,其他被测性状受影响程度表现为蘖位>种植密度>品种;(2)在主茎均能成穗的情况下,分蘖成穗率随蘖位和种植密度的升高而降低,大穗型品种川麦104的降幅大于多穗型品种扬麦15;(3)主茎产量贡献率随种植密度的升高而升高(35.12%~54.50%),分蘖1产量贡献率稳定在23.25%~25.50%,分蘖2和分蘖3的产量贡献率随种植密度升高而降低,分别为14.59%~23.22%和5.42%~16.77%;(4)主茎的穗粒数(35.94~44.13粒)和穗粒重(1.44~1.93 g)显著高于其分蘖,茎高、茎蘖收获指数和穗茎节长只在川麦104中、高种植密度下的分蘖3与其他茎蘖差异显著;穗长、可孕小穗数和不孕小穗数有随蘖位和种植密度升高而变劣的趋势。聚类分析得出:湖北稻茬小麦绿色高效生产模式,以主茎成穗为主体,低种植密度下增加分蘖1和分蘖2,争取分蘖3成穗为辅;中种植密度下争取分蘖1+分蘖2成穗为辅;而高种植密度下争取分蘖1成穗为辅。 相似文献