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施氮时期对夏玉米生长、干物质转运与产量的影响
Effects of nitrogen application at different stages on growth, yield, and dry matter transportation of summer maize
 [PDF]

周琦,张富仓,李志军,强生才,田建柯,李国栋,范军亮
- , 2018, DOI: 10.7606/j.issn.1000-7601.2018.01.12
Abstract: 为探索不同施氮时期对陕西关中地区夏玉米生长和产量的影响,通过桶栽施氮试验,研究了施氮总量相同的情况下,不同施氮时期对夏玉米的生长、产量和干物质分配转运的影响。试验设置7个施氮处理:N0不施氮(对照);N1拔节期一次性施入;N2大喇叭口期一次性施入;N3吐丝期一次性施入;N4拔节期、大喇叭口期分次施入;N5拔节期和吐丝期分次施入;N6拔节期、大喇叭口期和吐丝期分三次施入。结果表明:N4处理植株的产量显著高于其它处理,相对于拔节期一次施肥的N1处理增加了5.56%;N4处理的叶面积、成熟期干物质较其它处理高,相对于N1处理分别增长了8.03%和8.29%;N2、N5和N6处理的产量和干物质量显著性差异,相对于N1处理产量分别增长了4.0%、4.7%和4.1%,N1、N3处理的产量和干物质量较其它处理低,说明分次施肥可以提高玉米的产量和干物质量,最佳施肥方案为拔节期、大喇叭口期分次施入;N3、N5处理的干物质转运率相对较低,相对于产量较高的N4处理转运率分别降低5.5%和8.6%,但其花后同化物累积量相对于N4处理分别提高4.1%和7.8%,绿叶面积相对于其它处理较高,表明吐丝期追施氮肥可以延缓叶片衰老,从而提高玉米的产量。
Under the same nitrogen application amount, the effects of nitrogen application at different growth stages on growth, yield and dry matter transportation of summer maize in Guanzhong District of Shaanxi Province were explored. There were seven nitrogen treatments with the same nitrogen application amount: zero nitrogen application (N0, as control); all nitrogen application at elongation stage (N1); all nitrogen application at bell stage (N2); all nitrogen application at silking stage (N3); separate nitrogen application at elongation stage and bell stage (N4); separate nitrogen application at elongation stage and silking stage (N5); separate nitrogen application at elongation stage, bell stage and silking stage (N6). The results showed that the N4 significantly improved the yield and dry matter accumulation compared with the other treatments. Compare to N1, the yield of N4 was increased by 5.56%, the leaf area was increased by 8.03%, and the dry matter was increased by 8.29%. There were no significant difference between the yield and dry matter accumulation of N2, N5 and N6, whose average yield and dry matter accumulation increased were increased 4.0%, 4.7% and 4.1% compare to N1, respectively. The yield and dry matter accumulation of N1 and N3 were much lower than those of the other treatments, which indicate that separate nitrogen application could improve the yield and dry matter accumulation compared with all nitrogen application at a single growth stage. Nitrogen split application at elongation stage and bell stage was considered as the optimum nitrogen application mode. The dry matter translocation efficiency of N3, N5 were lower than the other treatments, but they maintained much more green leaf area at mature stage. The dry matter translocation efficiency of N3 was 5.5% less than that of N4, while the accumulation of dry matter after silking stage was increased by 4.1% compared with N4. The dry matter translocation efficiency of N5 was 8.6% less than that of N4, while the accumulation of dry matter after silking stage was
Effects of Water Stress, Nitrogen Levels and Application Times on Yield and Yield Components of Sunflower at Different Growth Stages  [cached]
GH. Omidi Ardali,M. J. Bahrani
Journal of Science and Technology of Agriculture and Natural Resources , 2011,
Abstract: The optimum levels of soil moisture and nitrogen are important to obtain higher yields. To investigate the effects of water stress, nitrogen levels and application times on yield and yield components of sunflower (Helianthus annuus L.), the cultivar Euroflor at different growth stages, a two year study (2006-007) was conducted at Research Fields of College of Agriculture, Shiraz University (Badjgah) using a split factorial design with four replications. Treatments were water stress at three levels, (non-stress and stress at flowering and seed formation) as main plot and three N levels (0, 70, 140 kg ha-1) and N application times (split application at planting and stem elongation, planting and heading, and stem elongation and heading) as subplot. Number of seed per head, 1000-seed weight, seed yield, Oil yield and HI were measured. Results showed that the effects of water stress and N rates on yield and yield components were significant, but the effects of N application times and interaction between water stress, nitrogen rates and application times were insignificant. Overall, the crop showed more sensitivity to drought stress at flowering time, and 70 kg N ha-1 is recommended for the region.
The Effect of Nitrogen and Phosphorus Fertilization on Growth, Yield and Quality of Forage Maize (Zea mays L.)  [PDF]
Hani A. Eltelib,Muna A. Hamad,Eltom E. Ali
Journal of Agronomy , 2006,
Abstract: In this study the effect of nitrogen and phosphorus application on growth, forage yield and quality of fodder maize was studied. The variety used was Giza 2. Nitrogen was applied at the rates of (0, 40 and 80 kg N ha-1), while phosphorus levels were (0, 50 and 100 kg P2O5 ha-1). Parameters studied were plant height, number of leaves per plant, stem diameter and Leaf Area Index (LAI). Moreover days to 50% tasseling, dry matter yield, crude protein and crude fiber contents were studied. Results showed that addition of nitrogen fertilizer significantly increased plant height, stem diameter and LAI. Phosphorus fertilization has no significant effect on the growth attributes. Application of nitrogen allowed the crop to reach 50% tasseling earlier. Phosphorus on the other hand has no effect on days to 50% tasseling. Nitrogen fertilization significantly increased the forage dry matter yield. In contrast phosphorus has no effect on the dry matter yield. Nitrogen was significantly increased the protein content of forage maize, on the other hand phosphorus has no effect on the crude protein content. Neither nitrogen nor phosphorus has a significant effect on the crude fiber content.
Growth and Yield Response of Wheat (Triticum aestivum L.) to Nitrogen Application at Different Growth Stages  [PDF]
M. Ayub,M.S. Sharar,A. Tanveer,M. Khaliq
Journal of Biological Sciences , 2001,
Abstract: Response of wheat (Triticum aestivum L.) cultivar Inqulab-91 to nitrogen application of 120 kg ha -1 at different growth stages (full at sowing, full at tillering, half at sowing and half at tillering, half at sowing and half at flowering, half at tillering and half at flowering and 1/3 at sowing, 1/3 at tillering and 1/3 at flowering) was studied under field conditions during 1993-94. Grain yield and various yield components like plant height, total number of tillers m -2, fertile tillers m -2, number of grains per spike, 1000-grain weight and harvest index were affected significantly by nitrogen application at different growth stages. Maximum grain yield of 84.31 q ha -1 was obtained where nitrogen was applied in three equal splits (1/3 at sowing, 1/3 at tillering and 1/3 at flowering) and it was followed by full at tillering and full at sowing which yielded 80.47 q ha -1 and 80.07 q ha -1, respectively. The nitrogen in three equal splits (1/3 at sowing, 1/3 at tillering and 1/3 at flowering) should be applied for getting higher grain yield of wheat in Faisalabad conditions.
Yield prediction and nitrogen recommendation in maize using normalized difference vegetation index  [PDF]
TB Karki
Agronomy Journal of Nepal , 2013, DOI: 10.3126/ajn.v3i0.9009
Abstract: A study was carried out using three maize genotypes with three levels of nitrogen (30 kg, 60 kg and 120 kg per hectare) during the summer season of 2010 and 2011with the aim of predicting maize (Zea mays L.) yield through the Normalized difference vegetation index (NDVI). The NDVI was recorded at different times throughout the growing season using a Greenseeker? handheld sensor. Significant effect of genotypes and nutrient levels on the NDVI was observed at different growth stages of maize. There was positive correlation between the NDVI and grain yield. In the first season, the correlation coefficients were 0.90, 0.92, 0.76 and 0.73, respectively at 15, 45, 75 and 110 days after seeding. In the second season, the correlation coefficients were 0.80, 0.92, 0.77 and 0.75 respectively at 15, 45, 75 and 110 days after seeding. The NDVI based N calculator showed that irrespective of genotypes, yield potentials under farmers' levels of nutrient management were almost half of the recommended doses of nitrogen. The amount of N to be top dressed decreased with increased crop duration. Grain yield varied significantly due to season, genotypes and nutrient levels. NDVI was affected due to season, stages of the crop (DAS), genotypes and nutrient levels. Interaction effects were significant for season x genotype, growth stage x genotype, growth stage x nutrient levels, genotype x nutrient levels and genotype x growth stage x nutrient levels. There was a strong positive correlation between NDVI and grain yields of hybrid maize at 15 and 45 DAS, but this correlation declined thereafter. This means that N top-dressed at or after 75 days of seed sowing will not increase grain yield as significantly as N applied earlier in the season. In contrast, topdressed N was producing significant effects on the open pollinated Rampur Composite even after 75 days of seed sowing. Further confirmation of the finding could be useful for top dressing N in the maize crop.
Effect of Variable Rates of Nitrogen and Phosphorus on Growth and Yield of Maize (Golden)
M. Maqsood,Amanat Ali Abid,Asif Iqbal,M. Iftikhar Hussain
Journal of Biological Sciences , 2001,
Abstract: Plant height was significantly affected by the variable rates of N and T5 (150-120-60) treatment produced the tallest plants than other treatments. The number of cobs plant 1 was significantly different from treatment T5 (150-120-60). The average grain weight (1000-grain weight) was maximum in T4 treatment which was at par with treatments T3 and T5. Grain yield of maize was significantly enhanced by T4 treatment than other treatment except for T5 treatment where it was statistically at par overall, average grain yield of 12.6 t ha 1 was obtained under the conditions of this experiment.
Effect of Nitrogen and Sulphur on Growth, Yield and Quality of Hybrid Maize (Zea mays L.)  [PDF]
Iqrar Hussain,Tariq Mahmood,Aman Ullah,Amjed Ali
Pakistan Journal of Biological Sciences , 1999,
Abstract: The experiment was laid out in randomized complete block design (RCBD) with three replications keeping a net plot size of 3.5 x 7.5 m to evaluate the effect of nitrogen and sulphur on growth, yield and quality of hybrid maize (cargill-707). Application of fertilizer @ 150 + 30 and 150 + 20 kg N and S per hectare, respectively greatly increased dry weight per plant, No. of grains per cob and grain weight per cob over other treatments. Similarly, highest grain yield of 8.59 tones per hectare was recorded from plot fertilized @ 150 kg N and 30 kg S per hectare. While maximum grain oil and crude protein contents were recorded from plot fertilized @ 150 + 30 and 150 + 20 kg N and S per hectare, respectively.
Soil nitrogen mineralization and its prediction in winter wheat-summer maize rotation system
冬小麦/夏玉米轮作体系中土壤氮素矿化及预测

JU Xiaotang,LIU Xuejun,ZHANG Fusuo,
巨晓棠
,刘学军,张福锁

应用生态学报 , 2003,
Abstract: The mineralization of soil nitrogen in winter wheat-summer maize growth season was studied with field experiment, and its prediction was made by interval leached aerial incubation combined with first-order dynamic model. The results showed that the amount of soil mineralized nitrogen had a large variation among years and crops. The soil nitrogen mineralization was lower in winter wheat growth season than in summer maize growth season, resulted in the yield increment of summer maize being not significant with increasing nitrogen fertilization rate. The amount of soil mineralized nitrogen occupied 31%-60% of the total nitrogen uptake by winter wheat and 62%-108% by summer maize. It was understandable why crop yield (especially summer maize) was not significantly response to applied nitrogen fertilizer. The amount of soil mineralized nitrogen decreased with increasing soil nitrogen supply. The mineralization was positive in normal nitrogen supply range(0-300 kg N.hm-2). The first order dynamic model could only predict the whole trend of mineralization in growth season, but could not reflect its variation in some growth stages. The role of the model was still important in view of the prediction of nitrogen mineralization before sowing.
Effect of Different Rates of Nitrogen and Phosphorus on Growth and Grain Yield of Maize (Zea mays L.)  [PDF]
M.S. Sharar,M. Ayub,M.A. Nadeem,N. Ahmad
Asian Journal of Plant Sciences , 2003,
Abstract: In a field experiment, growth and grain yield of maize cultivar golden as influenced by different NP combinations were studied. The different NP combinations significantly affected the plant height, cob bearing plant m-2, number of grains cob-1, 1000-grains weight, grain yield and harvest index. The number of cobs plant ̄1 was not influenced significantly by NP application. The NP application @ 180-130 kg ha-1 produced significantly higher grain yield (4.62 t ha-1) than all other NP combinations. The increase in yield was mainly due to higher 1000-grains weight, number of grains per cob and number of cobs bearing plant per plot. The results indicated that NP fertilizers should be applied @ 180-130 Kg ha-1 to obtain higher grain yield of maize cultivar golden under Faisalabad (Pakistan) conditions.
Effect of Different Nitrogen and Phosphorus Sources on The Growth and Grain Yield of Maize (Zea mays L.)
M. Ayub,M. Adil Choudhry,Asif Tanveer,M.M.Z. Amin
Pakistan Journal of Biological Sciences , 2000,
Abstract: The effect of different NP sources viz., urea + single super phosphate (SSP), Ammonium nitrate (AN) + SSP, ammonium sulphate (AS) + SSP, Urea + Triple super phosphate (TSP), AN + TSP and AS + TSP on the growth and grain yield of maize was studied in the Agronomic Research Area, University of Agriculture, Faisalabad during the year 1997. A quadruplicated experiment was arranged in a randomized complete block design measuring a net plot size of 3m x 8m. The combination of ammonium sulphate and single super phosphate produced significantly higher plant height, leaf area plant-1 and grain yield (5.41 t ha-1) than all other combinations. The increased yield was mainly associated with higher 1000-grain weight. Number of cobs plant-1 and number of grain rows cob-1 were statistically sigmilar in all combinations of NP sources. The combination of AS + SSP sems to be the most suitable one for obtaining higher grain yield of maize in Faisalabad conditions.
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