氮肥水平对不同基因型水稻氮素利用率、产量和品质的影响

以不同基因型的水稻品种日本晴、N70、N178和OM052为供试品种,氮肥采用尿素,按基肥(70%)和蘖肥(30%)两次施用,设置3个施氮水平(N用量设0、120、270 kg·hm^-2)的田间小区试验,研究氮素水平对水稻产量、氮素利用效率和稻米品质的影响,以期为氮肥合理施用和氮高效水稻品种创制提供科学依据.结果表明:施氮能增加水稻品种产量的原因是提高了有效穗数和每穗实粒数;与对照(0 kg·hm^-2)相比,当施氮量为120和270 kg·hm^-2时,OM052籽粒产量在4个品种中增幅最大,分别为41.1%和76.8%;品种产量增幅不同是由于氮素利用效率的差异,在120、270 kg·hm^-2氮处理下,4个供试品种中,日本晴籽粒产量和氮素农学利用率(40.90 g·g^-1、18.56 g·g^-1)都最低,为氮低效品种,OM052籽粒产量和氮素农学利用率(145.9 g·g^-1、81.24 g·g^-1)都最高,为氮高效品种.施N能够增加各品种的直链淀粉和蛋白质含量,使胶稠度变长,降低垩白率、垩白度和碱消值;随施氮量增加,热浆黏度、峰值黏度、回复值和崩解值递减,而消碱值递增.相关性分析表明,低N水平下,供试品种产量及产量构成因子与外观品质、蒸煮食味的相关性更显著.综上,OM052是一个籽粒产量和氮素利用效率“双高”基因型品种,合理施用氮肥可以显著增加水稻的有效穗数和每穗粒数,改善稻米籽粒品质,实现高产和优质的协同.     

The effect of deep placement and surface application of nitrogen fertilizers at different light intensities on growth and yield of wetland rice

Summary Lowland rice (RD 3) was cultivated in containers of clay soil submerged with 5 cm water under controlled conditions in the phytotron. Deep placement of urea supergranules 5 cm in the soil significantly enhanced both plant growth and fertilizer efficiency when the plants were cultivated under high light intensity (70 Wm^–2). At the highest urea level grain yield increased 119% above the control level, while growth and fertilizer efficiency was not as high when deep placement of calcium nitrate was used.The application of urea prills and calcium nitrate (18.4g Nm^–2) in two split doses on the soil surface increased grain yield as much as 91% above the control level. At the lower nitrogen concentration (9.2 g N m^–2), the urea prills were more efficient than calcium nitrate as indicated by the grain yield. The height of those plants fertilized by surface application was affected by the concentration and not the type of fertilizer. The number of tillers, however, was significantly higher on urea fertilized plants.When the rice plants were cultivated under low light intensity 930 Wm^–2), neither the nitrogen fertilizers nor the method of application had a significant effect on growth and yield.     

Development and field performance of nitrogen use efficient rice lines for Africa

Nitrogen (N) fertilizers are a major input cost in rice production, and its excess application leads to major environmental pollution. Development of rice varieties with improved nitrogen use efficiency (NUE) is essential for sustainable agriculture. Here, we report the results of field evaluations of marker‐free transgenic NERICA4 (New Rice for Africa 4) rice lines overexpressing barley alanine amino transferase (HvAlaAT) under the control of a rice stress‐inducible promoter (pOsAnt1). Field evaluations over three growing seasons and two rice growing ecologies (lowland and upland) revealed that grain yield of pOsAnt1:HvAlaAT transgenic events was significantly higher than sibling nulls and wild‐type controls under different N application rates. Our field results clearly demonstrated that this genetic modification can significantly increase the dry biomass and grain yield compared to controls under limited N supply. Increased yield in transgenic events was correlated with increased tiller and panicle number in the field, and evidence of early establishment of a vigorous root system in hydroponic growth. Our results suggest that expression of the HvAlaAT gene can improve NUE in rice without causing undesirable growth phenotypes. The NUE technology described in this article has the potential to significantly reduce the need for N fertilizer and simultaneously improve food security, augment farm economics and mitigate greenhouse gas emissions from the rice ecosystem.     

硫膜和树脂膜控释尿素对小麦产量、品质及氮素利用率的影响

通过田间试验,研究了硫膜和树脂膜控释尿素对小麦产量、品质和耕层土壤无机氮含量及氮素利用率的影响.结果表明：与普通尿素相比,硫膜和树脂膜控释尿素均能显著提高小麦籽粒产量和品质,增产幅度达10.4%～16.5%,小麦籽粒蛋白质和淀粉含量分别提高5.8%～18.9%和0.3%～1.4%;两种控释肥均能有效保持耕层土壤无机氮含量,且其氮素后移的功效满足了小麦生育后期对氮素的需求;有效提高了氮肥偏生产力,降低了土壤氮素依存率（降幅11.0%～17.3%）,提高了氮素利用率（增幅58.2%～101.2%）.其中,树脂膜控释尿素比硫膜控释尿素表现出更好的增产效应,实现了氮素的高效利用.     

长期施肥对黄土旱塬农田土壤有机磷组分及小麦产量的影响

研究长期施肥对黄土旱塬农田土壤有机磷组分及小麦产量的影响,可为提高磷素转化利用率及合理利用肥料提供理论支持。本研究依托长武旱塬农田生态系统长期(1984—2016年)定位试验站,选取不施肥(CK)、单施氮肥(N)、单施磷肥(P)、施氮磷肥(NP)、单施有机肥(M)、氮肥配施有机肥(MN)、磷肥配施有机肥(MP)、氮磷肥配施有机肥(MNP)8个处理,研究其对土壤有机磷组分、小麦产量和土壤性质的影响。结果表明: 长期施肥后土壤有机磷含量为244.7～429.1 mg·kg^-1,除N处理外,其余各处理有机磷含量比CK均显著增加了15.4%～47.9%。长期施用磷肥改变了黄土旱塬农田表层土壤(0～20 cm)各有机磷组分含量,MP、MNP处理显著提高了活性有机磷及中活性有机磷含量;N、P和NP处理显著降低了中稳性有机磷含量;N、P、NP、MN、MP、MNP处理均显著提高了高稳性有机磷含量。各处理土壤有机磷组分与总有机磷含量比值为:中活性有机磷>高稳性有机磷>活性有机磷>中稳性有机磷。长期施肥后,与CK相比,氮、磷肥配施,尤其是与有机肥配施,显著增加了小麦生物产量和籽粒产量。土壤指标中,有机质、速效磷和无机磷与小麦产量呈显著正相关。MP、M处理可以显著提高黄土旱塬黑垆土中的速效磷、总磷、总无机磷、活性有机磷和中活性有机磷含量,表明有机肥与磷肥配施可以提高该地区更容易被作物吸收的磷组分。总之,氮磷肥配施并配施有机肥可以提高该地区磷供给,对小麦增产有促进作用,对提高黄土旱塬地区土壤质量有重要意义。     

氮肥处理对氮素高效吸收水稻根系性状及氮肥利用率的影响

2011—2012年在土培条件下,以氮素吸收效率差异较大的15个常规籼稻为供试材料,研究氮肥运筹对不同氮效率品种根系性状、成熟期吸氮量及氮肥利用率的影响,分析影响氮高效水稻氮素吸收的主要根系性状。结果表明:(1)各氮肥处理下,成熟期吸氮量均表现为氮高效品种氮中效品种氮低效品种。适量增施氮肥及基肥+促花肥处理有利于氮高效品种吸氮量的增加,氮素吸收受品种、氮肥处理的显著影响。(2)在施氮量处理下,氮高效品种单株不定根数、单株根干重、单株不定根总长大或较大,单株根活力在常氮(N2)、高氮(N3)处理下有一定的优势;在施氮时期处理下,氮高效品种单株不定根数、单株不定根总长、单株根干重、单株根系总吸收面积、单株根系活跃吸收面积、抽穗期冠根比多数处理有优势;增施氮肥有利于促进氮高效品种单株不定根总长和单株根活力的提高,适量施氮有利于单株不定根数、单株根干重增加,前期施氮可促进不定根的发生和伸长,后期施氮有利于不定根的充实和根系生理性状的提高。此外,增施氮肥可提高各类品种冠根比;(3)在常氮、高氮处理下,氮高效品种氮肥利用率大于氮中效、氮低效品种。(4)提高单株不定根数、单株不定根总长、单株根活力及抽穗期冠根比有利于各类品种吸氮量的提高,增加根干重对氮高效品种吸氮量的提高也有显著的促进作用。结合相关分析与通径分析结果,抽穗期冠根比及单株不定根数、单株根活力、单株不定根总长、单株根干重是影响氮高效品种吸氮能力的主要根系性状。     

Interactive effects of molybdenum and phosphorus fertilizers on photosynthetic characteristics of seedlings and grain yield of Brassica napus

A pot experiment with acid yellow–brown soil was conducted to investigate the interactive effects of molybdenum (Mo) and phosphorus (P) fertilizers on the photosynthetic characteristics of seedlings and grain yield of Brassica napus which is sensitive to soil P and Mo deficiency. Both Mo and P fertilizers were applied at three levels (0 mg Mo kg^?1, 0.15 mg Mo kg^?1, 0.30 mg Mo kg^?1 soil; 0 mg P kg^?1, 80 mg P kg^?1, 160 mg P kg^?1 soil). The results showed that P fertilizer application increased grain yield, soluble sugar concentrations of seedling leaves, DM and P accumulation of seedling shoots of Brassica napus in the absence or presence of Mo fertilizer. In contrast, Mo fertilizer increased these parameters only in the presence of P fertilizer. Mo accumulation in shoots, chlorophyll concentrations and net photosynthesis rate (P _n) of seedling leaves were increased by both Mo and P fertilizers, particularly with the combination of the two fertilizers. The results also showed that the Mo and P fertilizers increased photosynthetic rate through two different mechanisms, with Mo increasing photosynthetic activity of mesophyll cells, and P increasing stomatal conductance. The results demonstrate that there was a synergetic effect on photosynthesis and grain yield between Mo and P fertilizers and it is conducive for Brassica napus growth to co-apply the two fertilizers.     

Effect of silica and magnesium on yield of upland rice in the humid tropics

Grain yield, dry-matter production, and susceptibility to grain discoloration syndrome of upland rice (Oryza sativa L.) in relation to nutrient supplies were studied in Ultisols in Nigeria's humid tropics. Nutrients identified as necessary to produce high dry matter were N, K, Mg, and Si. Among these nutrients, Mg and Si were found to be involved in the protection of rice plants against grain discoloration and their application increased the grain yield of 3 varieties by an average of 34%.     

有机无机肥配施提高麦-稻轮作系统中水稻氮肥利用率的机制

采用盆栽试验,研究了有机无机肥配施对麦-稻轮作系统中水稻氮素累积动态和土壤氮素供应动态的影响,并从微生物学角度探讨了有机无机肥协同提高水稻氮肥利用率的机制.结果表明：有机无机肥配施处理的土壤微生物生物量碳、氮和矿质态氮在水稻分蘖期前低于化肥处理,而在抽穗期至灌浆期显著高于其他处理.土壤氮素供应动态与水稻吸收利用氮素规律吻合程度最高,促进了水稻产量、生物量和氮素累积量的增加,显著提高了水稻的氮肥利用率.其主要机制是有机无机肥配施促进了土壤微生物繁殖,使其在水稻生育前期固持了较多的矿质氮,在水稻生育中、后期这些氮素逐渐被释放以供水稻吸收利用,较好地满足了水稻各阶段生长发育对氮素养分的需求.     

Effects of deep placement and surface application of urea on the yield of wetland rice in pot trials

Summary The effects of deep placement and surface application of urea fertilizer on the yield of rice grown in pots of alluvial clay soil covered with 5 cm water was studied under controlled conditions. Application of two levels of urea supergranules and prills (2 g and 4 g urea/0.1 m²) on the surface of submerged soil increased the vegetative growth and enhanced the grain yield as much as 85%. However, no difference in yield was found between urea prills applied in three split doses and one application of urea supergranules.Deep placement of two levels of urea supergranules in the soil at four different depths (2.5, 5.0, 10.0 and 15.0 cm) resulted in the highest yields. The fertilizer was most efficient when the highest concentration was placed in the soil at a depth of 5.0 cm. This application method increased the grain yield by 20% as compared with the soil surface application.     

The relation between some growth parameters and yield components of rice as influenced by nitrogen level and genotype

The effects of three levels of nitrogen (0, 2 and 4 g (NH₄)₂SO₄ per pot) were evaluated in four rice varieties, differing in grain size, under flooded conditions in a tropical environment. Addition of nitrogen increased plant height and leaf number on the main culm, and hastened flowering significantly in all varieties. It also increased the dry weights of leaf, and culm plus sheath at the maximum tillering stage, anthesis and harvest. The average dry weights of both leaf, and culm plus sheath increased significantly in all varieties until anthesis. Following anthesis, the dry weights of both leaf, and culm plus sheath of the large-seeded varieties, Zhu Lian and PP₆R, further increased mainly due to emergence of the late tillers, but decreased in the small-seeded varieties, IR 747 and P₃C₂₆. During grain-filling, vars Zhu Lian and PP₆R accumulated dry matter more than the other two varieties and did not use their reserve starch present in the culm plus sheath, presumably because of the lack of demand. By contrast, current photosynthesis and ‘reserve’ contributed about 70% and 30%, respectively, of the grain yield in IR 747 and P₃C₂₆. Addition of nitrogen increased grain yield significantly in all varieties. The yield increase in IR 747 and PP₆R was essentially due to increase in grain number, but that in P₃C₂₆ and Zhu Lian was due to increases in both grain size and grain number, the latter having much greater influence. Neither the percentage of filled spikelets nor the 1000-grain weight was influenced by nitrogen addition. It was concluded that grain number is the single most important yield component in rice. Path-coefficient analysis indicated that in a breeding programme involving these four rice varieties, the cross between Zhu Lian and P₃C₂₆ would be most successful in an effort to combine high spikelet number and large grain size.     

Comparative Proteomic Analysis Reveals Nitrogen Fertilizer Increases Spikelet Number per Panicle in Rice by Repressing Protein Degradation and 14-3-3 Proteins

The spikelet number per panicle is established in the early stages of panicle development. Nitrogen fertilizer application before panicle initiation is known to increase spikelet number, which is one of the most important traits in rice productivity determination. However, the basic proteomic mechanism remains poorly understood. The present study shows that nitrogen fertilizer significantly increased spikelet number and grain yield in rice. Proteomic variations were further analyzed in young panicles at the secondary panicle branch initiation and spikelet meristem initiation under nitrogen fertilizer treatment. Proteomic analysis identified 63 proteins with significant differential accumulation in young panicles under nitrogen fertilizer treatment. Proteolysis represents the largest functional category, which suggests that protein degradation is an important pathway in the response to nitrogen fertilizer. Importantly, nitrogen fertilizer significantly reduced 14-3-3 proteins, which interact with key enzymes associated with carbon and nitrogen metabolism, and the rice FT homologue Hd3a. Real-time PCR revealed that Hd3a signaling is also repressed by nitrogen fertilizer in leaves. This study contributes to a better understanding of the regulation of nitrogen fertilizers in the flowering pathway leading to panicle development. The identification of novel genes provides new insight into the profound impacts of nitrogen fertilizer on panicle development in rice.     

开放式空气CO2浓度增高对水稻产量形成的影响

在大田栽培条件下 ,研究开放式空气CO2 浓度增加 (FACE) 2 0 0 μmol·mol-1的处理对水稻产量及产量构成因素的影响 .结果表明 ,FACE处理对水稻株高和主茎叶片数没有明显影响 ,但使水稻生育进程加快 ,全生育期显著缩短 ,增加施N量可减缓FACE处理对水稻全生育期缩短的程度 ;FACE处理能显著增加分蘖数 ,极显著增加穗数 ,提高结实率 ,但使每穗颖花数显著减少 ;FACE处理能显著提高水稻产量 ,在高N条件下增产幅度更大 ;提高FACE处理的每穗颖花数和单位面积颖花数能极显著提高水稻产量 ,增加施N量是提高FACE处理每穗颖花数和单位面积颖花数的重要措施 .     

Using iron fertilizer to control Cd accumulation in rice plants: A new promising technology

Effects of two kinds of iron fertilizer, FeSO₄ and EDTA·Na₂Fe were studied on cadmium accumulation in rice plants with two rice genotypes, Zhongzao 22 and Zhongjiazao 02, with soil culture systems. The results showed that application of iron fertilizers could hardly make adverse effects on plant growth and rice grain yield. Soil application of EDTA·Na₂Fe significantly reduced the Cd accumulation in rice roots, shoots and rice grain. Cd concentration in white rice of both rice genotypes in the treatment of soil application of EDTA·Na₂Fe was much lower than 0.2 mg/kg, the maximal Cd permission concentration in cereal crop foods in State standard. However, soil application of FeSO₄ or foliar application of FeSO₄ or EDTA·Na₂Fe resulted in the significant increase of Cd accumulation in rice plants including rice grain compared with the control. The results also showed iron fertilizers increased the concentration of iron, copper and manganese element in rice grain and also affected zinc concentration in plants. It may be a new promising way to regulate Cd accumulation in rice grain in rice production through soil application of EDTA·Na₂Fe fertilizers to maintain higher content of available iron and ferrous iron in soils.     

减氮配施不同种类有机肥对玉米物质分配、转运与产量的影响

为倡导减量施用化学氮肥,探索科学施肥模式,以达到绿色、稳产、高产的种植目标,通过田间试验,以空白处理(CK₀)、常规施氮(CK₁)为对照,设置减氮比例和配施有机肥两因素试验,减氮比例设减氮20%(A₁)、减氮40%(A₂);配施有机肥设:不配施有机肥(B₀)、配施普通有机肥(B₁)、配施生物有机肥(B₂),研究了减氮配施不同种类有机肥对玉米物质积累分配、转运及产量的影响,为玉米化学氮肥减量增效技术提供科学依据。结果表明:随化学氮肥施用量的减少,玉米干物质积累量及产量降低;配施有机肥显著提高了干物质积累量、籽粒分配比例、吐丝后干物质对籽粒的贡献率和产量;减氮20%配施普通有机肥、生物有机肥处理较不配施有机肥处理,两年干物质积累量平均分别提高了31.38%和46.29%(P<0.05);产量分别提高了19.57%和23.78%,较常规施氮处理产量分别提高了7.15%和10.95%;减氮40%配施普通有机肥、生物有机肥处理较不配施有机...     

氮硅肥配施对水稻生长、产量及土壤肥力的影响

采用田间试验研究了氮硅肥配施对水稻生长、产量、养分吸收及土壤养分含量的影响。结果表明 ,氮、硅肥单施都能促进水稻生长及对养分的吸收 ,氮肥效果好于硅肥。氮硅肥配施下 ,水稻有效穗数、穗实粒数、千粒重、水稻产量以及水稻地上部生物量 ,植株氮、磷、钾、硅养分含量增幅均高于氮肥和硅肥单施。随施硅量增加 ,氮 /硅比率后期有明显下降趋势。氮硅配施提高了土壤速效氮含量和有效硅含量、降低了土壤速效钾含量 ,而对速效磷、pH、有机质及全氮无明显影响。     

播栽期对水稻产量和产量构成因素及生育期的影响

研究了不同播栽期对水稻产量和产量构成因素及生育期的影响。结果表明 ,随播栽期推迟 ,水稻产量有所降低。每穗成粒数减少是推迟播栽期引起水稻减产的主要原因 ,其次是千粒重的下降和成穗数的降低。针对目前的生产实际 ,提出了一些应对播栽期推迟的技术措施。     

Using iron fertilizer to control Cd accumulation in rice plants: A new promising technology

Effects of two kinds of iron fertilizer, FeSO4 and EDTA·Na2Fe were studied on cadmium accumulation in rice plants with two rice genotypes, Zhongzao 22 and Zhongjiazao 02, with soil culture systems. The results showed that application of iron fertilizers could hardly make adverse effects on plant growth and rice grain yield. Soil application of EDTA·Na2Fe significantly reduced the Cd accumulation in rice roots, shoots and rice grain. Cd concentration in white rice of both rice genotypes in the treatment of soil application of EDTA·Na2Fe was much lower than 0.2 mg/kg, the maximal Cd permission concentra- tion in cereal crop foods in State standard. However, soil application of FeSO4 or foliar application of FeSO4 or EDTA·Na2Fe resulted in the significant increase of Cd accumulation in rice plants including rice grain compared with the control. The results also showed iron fertilizers increased the concentra- tion of iron, copper and manganese element in rice grain and also affected zinc concentration in plants. It may be a new promising way to regulate Cd accumulation in rice grain in rice production through soil application of EDTA·Na2Fe fertilizers to maintain higher content of available iron and ferrous iron in soils.     

黑龙江省水稻品种跨积温区种植的产量和品质变化

采用在不同积温区布置田间试验的方法,比较研究了黑龙江省5个水稻主栽品种产量和品质随积温的变化.结果表明： 水稻产量随积温呈二次曲线变化,其相关程度因水稻品种而异;水稻穗数、穗粒数与积温呈极显著二次曲线关系,而千粒重与积温之间相关关系不显著;水稻籽实空瘪率从适宜积温区到低积温区显著增加,而从适宜积温区到高积温区变化不明显;水稻垩白率、整精米率与积温均呈极显著二次曲线关系,即垩白率和整精米率在适宜积温区分别有最小值和最大值存在;稻米蛋白质、直链淀粉含量和食味随积温变化不明显.根据对温度敏感程度的不同,可将水稻品种划分为温敏型、中间型、温钝型3类,其适宜栽培积温带宽度和允许栽培积温带宽度分别为300 ℃和420 ℃、360 ℃和440 ℃、380 ℃和520 ℃.根据积温因地制宜地选种水稻品种对于提高水稻产量、改善稻米品质十分重要.     

Over-expression of the rice LRK1 gene improves quantitative yield components

In rice ( Oryza sativa L.), the number of panicles, spikelets per panicle and grain weight are important components of grain yield. These characteristics are controlled by quantitative trait loci (QTLs) and are derived from variation inherent in crops. As a result of the complex genetic basis of these traits, only a few genes involved in their control have been cloned and characterized. We have previously map-cloned a gene cluster including eight leucine-rich repeat receptor-like kinase ( LRK ) genes in Dongxiang wild rice ( Oryza rufipogon Griff.), which increased the grain yield by 16%. In the present study, we characterized the LRK1 gene, which was contained in the donor parent (Dongxiang wild rice) genome and absent from the recurrent parent genome (Guichao2, Oryza sativa L. ssp. indica ). Our data showed that rice LRK1 is a plasma membrane protein expressed constitutively in leaves, young panicles, roots and culms. The over-expression of rice LRK1 results in increased panicles, spikelets per panicle, weight per grain and enhanced cellular proliferation, leading to a 27.09% increase in total grain yield per plant. The increased number of panicles and spikelets per panicle are associated with increased branch number. Our data suggest that rice LRK1 regulates rice branch number by enhancing cellular proliferation. The functional characterization of rice LRK1 facilitates an understanding of the mechanisms involved in cereal crop yield, and may have utility in improving grain yield in cereal crops.