Effects of a Dehydrating Agent on Dry Matter Accumulation and Nutritional Quality of Different Maize Varieties

The high water content of corn grain at harvest is a challenge in Northeast China,where the growing season is short.Using a dehydrating agent before harvest can help corn seeds dehydrate quickly.The dry matter accumulation and nutrient quality of maize were systematically studied by field experiments and instrumental analysis using maize varieties of different maturities as test materials.The results showed that the accumulation of dry matter was enhanced by an increased dosage of a dehydrating agent.When the dehydrating agent dosage reached 1800 mL•hm-2,the dry matter accumulation of early-maturing varieties increased by 24.1 g,and the water content decreased by 8.08%.Different maize varieties were treated with the same dose;early-maturing varieties showed significant effects on grain dry matter accumulation,and kernel dry matter accumulation increased by 7%.The effects of different doses on grain dehydration were obvious,and the effects on different maize varieties varied.Medium-ripening maize varieties showed the most significant effect,with a 19.5%reduction in water content.The effects of dehydrating agent doses on maize yield,grain nutrient quality and seed germination rate were not significant.Therefore,a dehydrating agent promoted the accumulation of dry matter in grain and accelerated the rapid dehydration.

The relationships between maize(Zea mays L.)lodging resistance and yield formation depend on dry matter allocation to ear and stem

Lodging is a critical constraint to yield increase.There appear to be tradeoffs between yield formation and lodging resistance in maize.Hypothetically,it is feasible to reduce lodging risk as well as increase grain yield by optimizing dry-matter allocation to different organs under different environments.A three-year field experiment was conducted using four maize cultivars with differing lodging resistances and five growing environments in 2018–2020.Lodging-susceptible(LS)cultivars on average yielded more than lodging-resistant(LR)cultivars when lodging was not present.The yield components kernel number per ear(KN)and thousand-kernel weight(TKW)were both negatively correlated with lodging resistance traits(stalk bending strength,rind penetration strength,and dry matter weight per internode length).Before silking,the LR cultivar Lishou 1(LS1)transported more assimilates to the basal stem,resulting in a thicker basal stem,which reduced dry matter allocation to the ear and in turn KN.The lower KN of LS1 was also due partly to the lower plant height(PH),which increased lodging resistance but limited plant dry matter production.In contrast,the LS cultivars Xianyu 335(XY335)and Xundan 20(XD20)produced and allocated more photoassimilates to ears,but limited dry matter allocation to stems.After silking,LS cultivars showed higher TKW than LR cultivars as a function of high photoassimilate productivity and high assimilate allocation to the ear.The higher lodging resistance of LS1 was due mainly to the greater assimilate allocation to stem after silking and lower PH and ear height(EH).High-yielding and high-LR traits of Fumin(FM985)were related to optimized EH and stem anatomical structure,higher leaf productivity,low assimilate demand for kernel formation,and assimilate partitioning to ear.A high presilking temperature accelerated stem extension but reduced stem dry matter accumulation and basal stem strength.Post-silking temperature influences lodging resistance and yield more than other environmental factors.These results will be useful in understanding the tradeoffs between KN,KW,and LR in maize and environmental influences on these tradeoffs.

The Enhancement of Soil Fertility,Dry Matter Transport and Accumulation,Nitrogen Uptake and Yield in Rice via Green Manuring

Readily available chemical fertilizers have resulted in a decline in the use of organic manure(e.g.,green manures),a traditionally sustainable source of nutrients.Based on this,we applied urea at the rate of 270 kg ha−1 with and without green manure in order to assess nitrogen(N)productivity in a double rice cropping system in 2017.In particular,treatment combinations were as follows:winter fallow rice-rice(WF-R-R),milk vetch rice-rice(MV-R-R),oil-seed rape rice-rice(R-R-R)and potato crop rice-rice(P-R-R).Results revealed that green manure significantly(p≤0.05)improved the soil chemical properties and net soil organic carbon content increased by an average 117.47%,total nitrogen(N)by 28.41%,available N by 26.64%,total phosphorus(P)by 37.77%,available P by 20.48%and available potassium(K)by 33.10%than WF-R-R,however pH was reduced by 3.30%across the seasons.Similarly,net dry matter accumulation rate enhanced in green manure applied treatments and ranked in order:P-R-R>R-R-R>MV-R-R>WF-R-R.Furthermore,the total leaf dry matter transport(t ha−1)for the P-R-R in both seasons was significantly higher by an average 11.2%,7.2%and 36%than MV-R-R,R-R-R,and WF-R-R,respectively.In addition,net total nitrogen accumulation(kg ha−1)was found higher in green manure applied plots compared to the control.Yield and yield attributed traits were observed maximum in green manure applied plots,with treatments ranking as follows:P-R-R>R-R-R>MV-R-R>WF-R-R.Thus,results obtained highlight ability of green manure to sustainably improve soil quality and rice yield.

Effects of Calcium Application Rate on Dry Matter Accumulation and Yield of Peanut

The effects of calcium application rate on dry matter accumulation and yield of peanut were studied under high-yielding field condition. The variety used for the study was Tang A8252( Spanish peanut). The results showed that number of full fruit,dry weight per plant,kernel yield,and pod yield all increased with calcium application increased,and they decreased when calcium application rate was more than150 kg/ha. Both the height of main stem and the length of side shoot decreased with calcium application increased. Therefore,to obtain the optimal agronomic character index and the highest yield benefit,the suggested calcium application rate would be 150 kg/ha for peanut.

Pattern of Growth and Dry Matter Accumulation in Some Improved Cowpea Varieties (<i>Vigna unguiculata</i>) Exposed to Alpha Nano Spin

Ten (10) cowpea varieties exposed to alpha nano spin were evaluated during the 2019 cropping season to access the role of alpha nano spin in their growth and dry matter accumulation at the Botanical garden of Federal University, Lafia. A Randomized Complete Block Design (RCBD) with four replications was used. The fourth replication was used for the destructive sampling over time. The seed was exposed to alpha nano spin before planting at 0, 20, 40 and 60 minutes respectively. Results of the study showed that the varieties differed significantly with respect to morphological traits studied (P < 0.05) as exposed to the alpha nanoparticles. Morphological traits such as vine length, number of leaves and above ground stems were significantly influenced by alpha nano spin bombardment. 40 mins alpha nano spin resulted in maximum accumulation of dry matter, leaf area and leaf area index. The traits evaluated were stable under alpha nano spin exposure, suggesting that they could be useful indices in creating genetic variability in each of the varieties.

Influence of Straw Incorporation on Maize Yield,N Accumulation and Remobilization on Slope Farmland in Northeast China

Slope farmland is a main type of agricultural land throughout northeast China.Long-term high intensity utilization and unreasonable farming have caused the deterioration of soil resources and a decrease in crop production.Here,it was hypothesized that crop straw incorporation might help to reduce nutrient losses and increase maize yields across time and space.A field experiment for testing straw management practices on maize across three slope positions(top,back and bottom slopes)was conducted in Northeast China in 2018 and 2019.In this study,the dry matter accumulation(DMA),N accumulation(NA),N remobilization,postsilking N uptake and grain yield were measured under SI(straw incorporation)and NSI(no straw incorporation)across three slope positions of 100-m-long consecutive black soil slope farmland during the maize(Zea mays L.)growth stages.Compared with NSI,SI significantly increased DMA and NA at the silking and maturity stages.SI typically increased the N remobilization in all slope positions,and significantly increased N remobilization efficiency and contribution of N remobilization to grain on the back and bottom slopes.However,post-silking N uptake was only increased by SI on the top slope.SI generally increased the crop yield in three slope positions.In the SI treatments,the bottom slope was the highest yield position,followed by the top,and then the back slopes,suggesting that the bottom slope position of regularly incorporated straw might have increased the potential for boosting maize yield.Overall,the study demonstrated the outsized potential of straw incorporation to enhance maize NA and then increase the grain yield in black soil slope farmland.

Effect of different film color mulching on dry matter and grain yield of oil flax in dry-land

Mulching can effectively maintain soil moisture;color of mulching film affects soil water storage capacity and further promote crop growth to improve grain yield.Field experiment was conducted to study effects of different film colors on dry matter accumulation(DMA)and grain yield of oil flax.Results showed that white plastic film mulching could increase leaf area,chlorophyll content and DMA.DMA of white film mulching and micro-ridge with soil covering was 53.0%higher than that of CK,and 7.8%higher than that of black film mulching.Mulching method also influenced DMA.Micro-ridge alone increased it by 13.7%than flat cultivation and soil covering improved another 7.6%under white film mulching.Both white and black film mulching with microridge could significantly improve grain yield.Black film mulching with micro-ridge and soil covering,white film mulching with micro-ridge and no soil covering significantly increased capsule number per plant,1,000-grain weight and grain yield of oil flax,compared with CK.Grain yield increased 29.0%and 28.9%respectively.These results indicated that the above mulching methods were suitable for high yield cropping pattern in dry-farming regions.

Influences of climate change on dry matter accumulating velocity of spring wheat and numerical simulation in arid and semi-arid regions

The influences of climate change on the velocity of dry matter accumulation of spring wheat and numerical simulation in arid and semi-arid regions under the condition of rainfalled agriculture or irrigated agriculture were quantitatively analysed by using the field experimental data. The results showed that the velocity of dry matter accumulation of spring wheat was declined with the temperature rising. The accumulating velocity would be declined 4.9 - 14.0% in irrigated agriculture area when air temperature rose in 0.5-4.0℃ ; but in rainfalled agriculture regions, the velocity of dry matter accumulation would be increased with the soil moisture increasing when air temperature rose in 0.5-1.0℃ and decreased when the air temperature rose in 3.0-4.0 ℃ .

Combined effects of high temperature and waterlogging on yield and stem development of summer maize

The purpose of this study was to identify the physiological mechanism underlying the effects of high temperature and waterlogging on summer maize.The stem development and yield of the maize hybrid Denghai 605 in response to high-temperature stress,waterlogging stress,and their combination applied for six days at the third-leaf,sixth-leaf,and tasseling stages were recorded.The combined stresses reduced lignin biosynthetic enzyme activity and lignin accumulation,leading to abnormal stem development.Reduction of the area and number of vascular bundles in stems led to reduced dry matter accumulation and allocation.Decreased grain dry weight at all three stages reduced grain yield relative to a control.In summary,high temperature,waterlogging,and their combined stress impaired stem development and grain yield of summer maize.The combined stresses were more damaging than either stress alone.

Night warming increases wheat yield by improving pre-anthesis plant growth and post-anthesis grain starch biosynthesis

Global climate change is characterized by asymmetric warming,i.e.,greater temperature increases in winter,spring,and nighttime than in summer,autumn,and daytime.Field experiments were conducted using four wheat cultivars,namely‘Yangmai 18’(YM18),‘Sumai 188’(SM188),‘Yannong 19’(YN19),and‘Annong 0711’(AN0711),in the two growing seasons of 2019-2020 and 2020-2021,with passive night warming during different periods in the early growth stage.The treatments were night warming during the tillering-jointing(NW_(T-J)),jointing-booting(NWJ-B),and booting-anthesis(NWB-A)stages,with ambient temperature(NN)as the control.The effects of night warming during different stages on wheat yield formation were investigated by determining the characteristics of dry matter accumulation and translocation,as well as sucrose and starch accumulation in wheat grains.The wheat yields of all four cultivars were significantly higher in NW_(T-J)than in NN in the 2-year experiment.The yield increases of semi-winter cultivars YN19 and AN0711 were greater than those of spring cultivars YM18 and SM188.Treatment NW_(T-J)increased wheat yield mainly by increasing the 1,000-grain weight and the number of fertile spikelets,and it increased dry matter accumulation in various organs of wheat at the anthesis and maturity stages by increasing the growth rate at the vegetative growth stage.The flag leaf and spike showed the largest increases in dry matter accumulation.NW_(T-J)also increased the grain sucrose and starch contents in the early and middle grain-filling stages,promoting yield formation.Overall,night warming between the tillering and jointing stages increased the pre-anthesis growth rate,and thus,wheat dry matter production,which contributed to an increase in wheat yield.

Effects of post-silking water deficit on the leaf photosynthesis and senescence of waxy maize

Waxy maize is widely cultivated under rainfed conditions and frequently suffers water shortage during the late growth stage.In this study,a pot trial was conducted to examine the effects of post-silking drought on leaf photosynthesis and senescence and its influence on grain yield.Two waxy maize hybrids,Suyunuo 5(SYN5)and Yunuo 7(YN7),were grown under the control and drought(soil moisture content was 70–80%and 50–60%,respectively)conditions after silking in 2016 and 2017.The decrease in yield was 11.1 and 15.4%for YN7 and SYN5,respectively,owing to the decreased grain weight and number.Post-silking dry matter accumulation was reduced by 27.2%in YN7 and 26.3%in SYN5.The contribution rate of pre-silking photoassimilates transferred to grain yield was increased by 15.6%in YN7 and 10.2%in SYN5,respectively.Post-silking drought increased the malondialdehyde content,but decreased the contents of water,soluble protein,chlorophyll,and carotenoid in the leaves.The weakened activities of enzymes involved in photosynthesis(ribulose-1,5-bisphosphate carboxylase and phosphoenolpyruvate carboxylase)and antioxidant system(catalase,superoxide dismutase and peroxidase)reduced the photosynthetic rate(Pn)and accelerated leaf senescence.The correlation results indicated that reduced Pn and catalase activity and increased malondialdehyde content under drought conditions induced the decrease of post-silking photoassimilates deposition,ultimately resulted in the grain yield loss.

Differences in Chlorophyll Fluorescence Parameters, Yield and Its Components Between Different Genotypes of Wheat Under Waterlogging Conditions at Anthesis

Waterlogging is one of the most factors limiting wheat production in the middle and lower reaches of the Yangtze River Plain of China,especially in the middle and late stages of wheat.Wheat varieties‘Jingmai102’(JM102)and‘Yangmai158’(YM158)were planted to study the dynamic changes of photosynthetic characteristics in flag leaf and the influence of waterlogging at anthesis on the yield and components and dry matter accumulation and remobilization of winter wheat in above ground.The results showed that the SPAD values slightly increased at 1 day after anthesis(d),and then kept decreasing with the increase of waterlogging time.The decrease in SPAD value was more remarkably in YM158 than that in JM102.As for the chlorophyll fluorescence parameters,the photochemical efficiency(Fv/Fm),potential activity(Fv/Fo)of photosystem II,and electronic transmission(Fm/Fo)on photosystem II increased first and then decreased with the increase of waterlogging days after anthesis.The quantum ratio of heat dissipation(Fo/Fm)had a tendency opposite to that of Fv/Fm,and the change range of JM102 was lower than that of YM158.For the grain yield and components,waterlogging at anthesis decreased the dry weight of single stem,grain yield,1 000-kernel weight,spikelet per panicle,and harvest index,and the reduction of JM102 was smaller than that of YM158.As for the accumulation and remobilization of dry matter,the accumulation of dry matter after anthesis decreased significantly under waterlogging condition(WL),and the reduction of JM102 was smaller than that of YM158.In conclusion,waterlogging at anthesis significantly affected the photosynthetic characteristics,yield and components in both varieties,but different varieties exhibited different tolerances to waterlogging stress and YM158 was more sensitive to water stress than JM102.

Morpho-Physiological Response of Oryza glaberrima to Gradual Soil Drying

Soil drought occurrence during dry season has been the main constraint, besides prolonged flooding during rainy season, in increasing cropping intensity and rice productivity in tropical riparian wetland. Use of drought tolerant rice genotype might be a suitable option for overcoming such problem. This study focused on the effects of gradual soil drying during early vegetative growth stage on morphological and physiological traits of five Oryza glaberrima genotypes, namely RAM12, RAM14, RAM59, RAM97 and RAM101, and two Oryza sativa subsp japonica genotypes, i.e. Koshihikari and Minamihatamochi. The plants were subjected to 6 d of gradual soil drying condition from 15 days after transplanting(DAT) to 20 DAT, and were allowed to recover until 22 DAT. Gradual soil drying reduced plant growth as indicated by dry mass accumulation. Drought reduced stomatal conductance and increased leaf rolling score of all the genotypes. All the genotypes showed comparable response on stomatal conductance, but O. glaberrima genotypes performed higher in leaf rolling recovery. Meanwhile, O. sativa genotypes decreased total leaf area and specific leaf area, but increased specific leaf weight in order to avoid further damages due to drought stress. Drought tolerance mechanisms in RAM101, RAM12, RAM59 and RAM14 were associated with leaf morpho-physiological responses, root traits and dry biomass accumulation.

Effect of Different Nitrogen Fertilizer Application Strategies on Rice Growth and Yield

Nitrogen fertilizer is an important factor for crop production. The N application strategies named as former nitrogen moved backward( FNMB) are tested in three ecological regions to optimize the N application in rice. The dry matter accumulation and distribution,yield and quality are studied to understand the formation of yield and quality of rice under different N application strategies. The result indicates that former nitrogen moved backward( FNMB) can increase tiller number and dry matter accumulation; effective ears and yield can be increased with the increase of fertilization; rational nitrogen application can help to establish scientific group structure,harmonize yield component,and then achieve high ratio of input to output and benefit.

Late spring cold reduces grain number at various spike positions by regulating spike growth and assimilate distribution in winter wheat

Late spring cold(LSC) occurred in the reproductive period of wheat impairs spike and floret differentiation during the reproductive period,when young spikelets are very cold-sensitive.However,under LSC,the responses of wheat spikelets at various positions,leaves,and stems and the interactions between them at physiological levels remain unclear.In the present study,two-year treatments at terminal spikelet stage under two temperatures(2 C,-2 C) and durations(1,2,and 3 days) were imposed in an artificial climate chamber to compare the effects of LSC on grain number and yield in the wheat cultivars Yannong 19(YN19,cold-tolerant) and Xinmai 26(XM26,cold-sensitive).The night temperature regimes were designed to reproduce natural temperature variation.LSC delayed plant growth and inhibited spike and floret differentiation,leading to high yield losses in both cultivars.LSC reduced dry matter accumulation(DMA,g) in spikes,stems,and leaves,reducing the DMA ratios of the spike to leaf and spike to stem.Plant cell wall invertase(CWINV) activity increased in upper and basal spikelets in YN19,whereas CWINV increased in middle spikelets in XM26.Under LSC,soluble sugar and glucose were transported and distributed mainly in upper and basal spikelets for glume and rachis development,so that spike development was relatively complete in YN19,whereas the upper and basal spikelets were severely damaged and most of the glumes in middle spikelets were relatively completely developed in XM26,resulting in pollen abortion mainly in upper and basal spikelets.The development of glumes and rachides was influenced and grain number per spike was decreased after LSC,with kernels present mainly in middle spikelets.Overall,reduced total DMA and dry matter partitioning to spikes under LSC results in poor spikelet development,leading to high losses of grain yield.

Dynamics of physiological characteristics and dry matter accumulation under rain-water storage irrigation

Photosynthesis is related to dry matter accumulation in aboveground part of rice plant,which is the direct factor of production.This study carried out research on physiological indicators and the relationship between photosynthesis and dry matter accumulation under different water management in paddy field.In general,the photosynthetic and physiological indicators showed the trend of increasing and then decreasing with the growth stage of rice.Experimental results showed that,chlorophyll content and leaf area index of rice leaves showed a quadratic curve positive correlation.Canopy light transmission reached the maximum at heading-flowering stage,and it had quadratic relationship with leaf area index,while it showed extremely positive correlation under rain-water storage irrigation mode.Photosynthetic rate(Pn)and transpiration rate(Tr)had quadratic curve positive correlation with chlorophyll content.The water condition under rain-water storage was favorable for dry matter accumulation in panicle.After multiple regression and main factor analysis,canopy light transmission,light transmission coefficient and Pn were main factors related to dry matter accumulation.The conclusions in this article were helpful for promoting rice yield in practice.

Characterization of low-N responses in maize(Zea mays L.) cultivars with contrasting nitrogen use efficiency in the North China Plain

Over-use of N fertilizer in crop production has resulted in a series of environmental problems in the North China Plain(NCP).Thus,improvement of nitrogen use efficiency(NUE)in summer maize has become an effective strategy for promoting sustainable agriculture in this region.Using twenty maize cultivars,plant dry matter production,N absorption and accumulation,yield formation,and NUE in summer maize were investigated under three N levels in two growing seasons.Based on their yield and yield components,these maize cultivars were categorized into four groups including efficient-efficient(EE)cultivars,high-nitrogen efficient(HNE)cultivars,low-nitrogen efficient(LNE)cultivars and nonefficient-nonefficient(NN)cultivars.In both two seasons,the EE cultivars improved grain yield together with increased plant biomass,and enhanced accumulative amounts as well as higher average grain yields than the other cultivar groups under deficient-N conditions.Significant correlations were observed between yield and kernel numbers(KN),dry matter(DM)amount and N accumulation at both post-silking and maturity stages.DM and N accumulation at late growth stage(i.e.,from silking to maturity)contributed largely to the enhanced yield capacity and improved NUE under N-deficient conditions.Compared with the NN cultivars,the EE cultivars also showed increased N assimilation amount(NAA)and N remobilization content(NRC),and elevated N remobilization efficiency(NRE),NUE and nitrogen partial factor productivity(PFPN).Our investigation has revealed N-associated physiological processes and may provide guidance for cultivation and breeding of high yield and NUE summer maize under limited N conditions in the NCP.

Effects of Irrigation Schedules on Photosynthetic Carbon Assimilation of Winter Wheat (Triticum aestivum L.) in North China Plain:from Leaf to Population

A field experiment was conducted to elucidate the regulation mechanism of different irrigation schedules on population photosynthetic of winter wheat. The experiment included five irrigation schedules, such as no irrigation (W0), irrigation once at jointing (W1j) or at booting (W1b), irrigation twice at jointing and booting (W2), and irrigation three times at jointing, booting and grain-filling (W3) and three planting densities, such as 180 (D1), 300 (D2) and 450 (D3) seedlings per square meter. The results indicated that irrigation significantly improved population photosynthesis. The relationship between population photosynthesis and irrigation time/volume was to some extent parabolic. Improvements in population photosynthesis (resulting from more irrigation time/volume) were mainly related to increase in leaf area index and population light interception. Population photosynthesis exhibited a significantly negative correlation with canopy light transmittance. Population photosynthesis at grain filling stage was significantly positively correlated with dry matter accumulation at post-anthesis and grain yield. Main effects and partial correlation analysis showed that population photosynthesis of W0, W1j, W1b and W3 were regulated by canopy light transmittance and leaf area. On the other hand, population photosynthesis of W2 was mainly influenced by flag leaf photosynthetic rate. On this basis, planting 300 seedlings per square meter was the optimum combination. The combination of W2D2 increased population photosynthesis during mid-late growth stages and extended high population photosynthesis duration, which ultimately increased grain yield.

增密对不同品种胡麻干物质积累分配和产量形成的影响

通过分析增密条件下胡麻干物质积累分配及与籽粒产量形成的相关关系,探讨不同品种胡麻增密后产量差异,为西北旱区胡麻高产栽培模式提供理论支撑。2017-2018年,在陇中黄土高原半干旱丘陵沟壑区,设置3个胡麻品种:定亚23号(V1)、晋亚10号(V2)、轮选3号(V3),以及3个种植密度:300(D1,传统密度:低密度)、420(D2,增密40%:中密度)和540(D3,增密80%:高密度)万株/hm^(2),研究增密条件下不同品种胡麻干物质积累分配、叶茎干物质转运率和对籽粒的贡献率、叶面积指数、产量及产量构成的差异,以期为优化试区胡麻高产高效栽培模式提供理论依据。两年种植密度均显著影响胡麻干物质积累量,盛花期,高密度干物质积累量较中、低密度分别提高50.9%、79.5%,青果期提高27.9%、38.7%,成熟期分别提高18.1%和55.6%;不同品种比较,2018年轮选3号干物质积累量较晋亚10号和定亚23号高9.6%和8.5%。2017年高密度处理的胡麻叶片干物质转运量较中、低密度分别提高35.1%、69.8%,2018年提高85.4%、229.7%,叶对籽粒的贡献率高密度处理较中、低密度分别提高40.0%和130.9%;从盛花至成熟期,轮选3号在高密度下可保持较高的LAI,较其他处理平均高出42.6%~87.2%和27.1%~53.8%。两年度下,晋亚10号在中密度下籽粒产量均高于其他处理7.8%~25.2%和7.0%~15.2%,其主要原因是提高了胡麻每公顷成株数。

头季穗肥和促芽肥对再生稻再生芽生长及产量形成的影响

【目的】研究头季氮素穗肥和促芽肥运筹对再生稻再生芽生长、干物质积累及产量形成的影响及可能途径。【方法】采用裂裂区设计,品种为主区(丰两优香1号和两优6326),2个头季穗肥为副区(N_(1),30 kg/hm^(2);N_(2),60 kg/hm^(2)),3个再生季促芽肥为副副区(T_(1)、T_(2)和T3分别为0、50和100 kg/hm^(2)),考查在不同氮肥运筹下两品种再生芽生长状况、干物质积累与分配、产量及产量构成因子。【结果】头季高氮素穗肥对丰两优香1号头季产量无显著影响,显著提高两优6326头季产量,对两品种再生力和再生季产量无显著影响。增施促芽肥显著降低两品种头季齐穗前茎鞘干物质转运量和收获指数,提高不同节位再生芽芽长、活芽数和再生力,促进再生季齐穗后干物质积累,提高了再生季产量。此外,头季氮素穗肥和促芽肥对再生季产量具有显著交互作用。丰两优香1号在N_(1)T_(3)处理下周年产量最高(14.46 t/hm^(2)),两优6326在N_(2)T_(2)处理下周年产量最高(14.44 t/hm^(2))。单茎再生芽长、活芽数和芽生长速率与头季齐穗后干物质积累量呈显著正相关,与头季收获指数和头季齐穗前干物质转运量呈显著负相关,与再生力和再生季产量呈显著正相关。【结论】头季高氮素穗肥对丰两优香1号和两优6326再生季产量没有显著影响,促芽肥施用可促进两品种再生芽生长,提高再生力和再生季产量,但过高施用量并没有进一步提高产量。头季穗肥和促芽肥互作显著影响再生季产量。施用促芽肥可通过增加头季茎鞘干物质积累来促进再生芽生长、再生季干物质积累与成穗,从而提高再生力和再生季产量。再生稻生产中应合理运筹穗肥和促芽肥以实现较高的再生季和周年产量。低头季穗肥和高促芽肥、高穗肥高促芽肥可分别实现丰两优香1号、两优6326周年高产。