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2007—2010小麦生长季,以高产小麦品种济麦22为材料,利用测墒补灌技术确定灌水量,研究高产条件下条旋耕、深松+条旋耕、旋耕、深松+旋耕和翻耕5种耕作方式对小麦的耗水特性、干物质积累与分配、籽粒产量及水分利用效率的影响。结果表明,深松+条旋耕和深松+旋耕的农田耗水量和0~200 cm土层的土壤贮水消耗量高于条旋耕和旋耕处理,深松+条旋耕的小麦株间蒸发量低于深松+旋耕和翻耕处理。深松+条旋耕和深松+旋耕成熟期的干物质积累总量、籽粒的干物质分配量及分配比例和开花后干物质同化量对籽粒的贡献率均高于翻耕处理,翻耕高于旋耕和条旋耕处理,条旋耕最低。深松+条旋耕三个生长季均获得高的籽粒产量,分别为9 409.01 kg hm-2、9 613.86 kg hm-2和9 698.42 kg hm-2,与深松+旋耕处理无显著差异,翻耕处理次之,条旋耕和旋耕低于上述处理,条旋耕最低。深松+条旋耕处理的水分利用效率在2007—2008生长季与深松+旋耕处理无显著差异;在2008—2010生长季最高,分别为21.39 kg hm-2 mm-1和22.09kg hm-2 mm-1,深松+旋耕处理次之,旋耕和条旋耕低于翻耕处理。在本试验条件下,深松+条旋耕是兼顾高产节水的最优耕作方式。  相似文献
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孔凡磊  袁继超  张海林  陈阜 《作物学报》2013,39(9):1612-1618
为了解华北地区小麦–玉米两熟区不同耕作模式对冬小麦生育进程、群体大小及产量形成的影响,2009–2011年通过田间定位试验比较了免耕(NTS)、旋耕秸秆还田(RTS)、翻耕秸秆还田(CTS)和翻耕秸秆不还田(CT) 4种耕作模式对冬小麦生长发育和产量的影响。结果表明,RTS、CTS和CT处理对冬小麦生育进程、群体大小、籽粒灌浆和产量无显著影响,而NTS处理推迟了小麦生育进程,造成明显的贪青晚熟。在基本苗差异不大的情况下,NTS处理的单株分蘖显著低于其他处理,群体数量和有效穗数不足,降低了干物质积累量,最终产量最低,较CT处理有效穗数低14.4%~16.9%,产量低16.4%~18.3%。虽然NTS处理推迟了冬小麦的生育进程,分蘖少穗数不足导致减产,但其粒灌浆时间较长,千粒重显著高于其他处理。因此,通过增加播种量和选择分蘖能力强的品种等技术保证免耕小麦群体数量,是华北地区冬小麦免耕技术研究应用亟需解决的问题。  相似文献
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This study was conducted for 3 years in silty clay loam (Aquic hapludoll) associated with water tables fluctuating between 0.05 and 0.96 m depths from the surface. Tillage treatments for rice (Oryza sativa L.) were puddling by four passes of rotary puddler (PR), reduced puddling (ReP) for two passes of rotary puddler, conventional puddling (CP) and direct seeding without puddling (DSWP) in four replications. Tillage treatments for wheat (Triticum aestivum L.) were zero tillage (ZT) and conventional tillage (CT) superimposed over the plots of rice tillage treatments. Puddling caused a significant reduction in saturated hydraulic conductivity (Ks), infiltration rate (IR), and specific volume (Rv). The reduction in Ks in the PR plot at 30 days after transplanting was 27 and 46% (3-year average) higher than in the ReP and DSWP plots, respectively, but was statistically at par with that in the CP plot in the surface tilled layer. This indicates that puddling by four passes of rotary puddler and that by conventional method adopted by farmers in those conditions gives the same level of control on percolation rate. Highest rice yield (5607 kg ha−1) was obtained in the PR plot, which was statistically equal to that in the ReP plot. Wheat yield was highest (4020 kg ha−1) in the DSWP plot of rice under CT condition. Total average grain production (rice + wheat) was highest under ReP–CT treatment combination. Results thus show that quality of soil puddle obtained by half the efforts in conventional puddling was sufficient for a significantly high yield of rice with minimum deterioration of soil properties. Similarly, wheat sowing by conventional tillage in such a reduced puddling plots of rice was sufficient for a significantly high yield of wheat.  相似文献
4.
Two experiments were carried out at Pegões (central Portugal) to determine the potential N mineralization in a pulse amended disturbed and undisturbed soil incubated at several temperatures, and to evaluate for 2 years the yield and N2 fixation capacity of sweet lupine (Lupinus albus L. cv. Estoril) inoculated with a mixture of rhizobia strains or nodulated by indigenous soil bacteria and submitted to conventional tillage or no-till practices. A completely randomized block design for soil mobilization with three replicates was used for the laboratory study, and completely randomized blocks for inoculation and tillage treatments with four replicates were used for the lupine yield and N2 fixation experiment. Residue N immobilization occurred immediately after mature residue return to the soil independent of temperature, and was greater at 7 °C especially in the disturbed topsoil. Greater immobilization was also observed by doubling the amount of mature residue incorporated in the soil. This was expected since soil microorganisms would be in direct contact with the fresh organic matter and would be provided with more organic carbon under these circumstances. Nitrogen mineralization proceeded after 5 days of amendment. Potential N mineralization was higher at 25 °C than at 18 or 7 °C, for both conventional and no-till practices. At 25 °C, 42% of buried residue-15N was released over 210 days, at a smaller rate than 18 °C (49%) over 81 days. Lupine yield and N2 fixation capacity were similar in plots that were not inoculated and those receiving the mixture of three rhizobia strains. White lupine had an efficient symbiosis with indigenous soil rhizobia at pod-filling (>99%, >100 kg N ha−1 year−1) which was not affected by tillage. At this stage, plant residue including visible roots and nodules accounted for a soil N input of +96 kg ha−1 year−1 (91% of crop N), showing the large soil N benefit by the crop at this stage. The lupine residue at pod-filling stage can be used as a green manure under the conditions of organic farming systems. The apparent N “harvest” index of the pulse at pod-filling was only 9% though at maturity phase it should result in a higher value and the legume will show a lower fertilizer N value.  相似文献
5.
One experiment lasting for two years was carried out at Pegões (central Portugal) to estimate the impact of mature white lupine residue (Lupinus albus L.) on yield of fodder oat (Avena sativa L. cv. Sta. Eulalia) as the next crop in rotation, comparing with the continuous cultivation of cereal, under two tillage practices (conventional tillage and no-till) and fertilized with five mineral nitrogen (N) rates, with three replicates. Oat as a first crop in the rotation provided more N to the agro-ecosystem (63 kg N ha−1) than did lupine (30–59 kg N ha−1). This was at a cost of 100 kg of mineral N ha−1, whereas lupine was grown without addition of N. A positive response of oat as a second crop was obtained per kg of lupine-N added to the system when compared with the continuous oat–oat. The cereal also responded positively to mineral N in the legume amended soil in contrast with the oat–oat sequence where no response was observed, partly due to the fast mineralization rate of lupine residue and a greater soil N immobilization in the continuous oat system. Each kg N ha−1 added to the soil through the application of 73 kg DM ha−1 mature lupine residue (above- and belowground material) increased by 72 kg DM ha−1 the oat biomass produced as the second crop in rotation when 150 kg mineral N ha−1 were split in the season, independent of tillage practice. Mature legume residue conserved in the no-tilled soil depressed the yield of succeeding cereal but less than the continuous oat–oat for both tillage practices, where the application of mineral N did not improve the crop response.  相似文献
6.
为探讨砂姜黑土农田适宜的耕作方式,提升砂姜黑土农田地力及作物产量,发挥地域资源优势,以百农207为试验材料,通过田间试验,研究了免耕、旋耕(15cm)和深耕(30cm)3种耕作方式对砂姜黑土农田土壤容重、土壤含水量、硝态氮含量及小麦籽粒产量的影响。结果表明,在小麦越冬期和成熟期,3种耕作方式0~10cm土层土壤容重差异不显著(P>0.05),但深耕处理显著降低了10~40cm土层土壤容重(P<0.05)。在小麦苗期,3种耕作方式对0~40cm土层土壤含水量影响规律不明显(P>0.05),但在小麦越冬期、拔节期、成熟期,深耕处理显著增加了0~40cm土层土壤含水量(P<0.05)。在小麦成熟期,0~40cm土层土壤硝态氮含量均为免耕>旋耕>深耕。与免耕处理相比,深耕处理通过增加小麦穗粒数和千粒重,使籽粒产量增加9.79%。综合研究区的土壤性质、作物生长、自然环境等因素,小麦季30cm深耕可以降低土壤容重,增加土壤含水量,提高小麦籽粒产量,可作为砂姜黑土农田适宜的耕作方式。  相似文献
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