植生粒对三江源退化高寒草地植物群落组成及生物量的影响

【目的】近年来,由于气候变暖和超载过牧,三江源高寒草地出现退化,导致源区生态环境恶化,草地植被多样性和生物量降低,而补播是恢复草地退化常用的有效方法之一,植生粒适用于高寒草原近自然补播恢复,本研究通过探究植生粒对三江源区高寒草地植物组成及生物量的影响,从而为高寒退化草地的恢复及可持续利用提供科学依据。【方法】以三江源退化高寒草地为研究对象,利用组成比例不同的植生粒对其进行补播。【结果】补播5种配方植生粒均增加了以嵩草类植物为优势种的群落重要值,提高了物种数量、植被盖度,并提高了除C处理外的群落的Shannon-wiener多样性指数,降低了Pielou均匀度指数。补播组成为15 g草种、8.5 g复混肥和71.5 g凹凸棒土的植生粒可以更好地促进豆科植物的生长,该配方处理下豆科植物的生物量增加量为8.35 g/m^(2);补播15 g草种、15 g复混肥和65 g凹凸棒土的植生粒显著增加了禾本科植物地上生物量、莎草科植物地上生物量,增加量分别为3.6和8.95 g/m^(2),降低了豆科植物地上生物量,说明该植生粒可以更好地促进禾本科和莎草科植物的生长。【结论】添加植生粒对恢复退化高寒草地植被多样性,增加牧草产量具有重要意义。

长江中游地区不同钾肥用量对油菜生物量、产量和养分吸收利用的影响

2021~2022年在长江中游地区湖北省武汉市江夏区开展田间试验,研究不同氯化钾施用量对油菜苗期及成熟期生物量、产量和养分吸收分配的影响。试验设置6个氯化钾施用量处理,分别为K_(0)(K_(2)O 0 kg/hm^(2))、K_(30)(K_(2)O30 kg/hm^(2))、K_(60)(K_(2)O 60 kg/hm^(2))、K_(90)(K_(2)O 90 kg/hm^(2))、K_(120)(K_(2)O 120 kg/hm^(2))和K_(150)(K_(2)O 150 kg/hm^(2))。结果表明,在一定范围内,随着钾肥用量的提高,油菜苗期以及成熟期各部位生物量和产量显著增加,其中最高增产量和增产率分别为1199.6 kg/hm^(2)和57.2%。当施钾量超过120 kg/hm^(2)后油菜生物量和产量均不再显著增加。油菜苗期以及成熟期各部位钾含量随着钾肥用量的增加而显著提高,氮含量均无显著变化,但成熟期籽粒中的磷含量随着施钾量的提高而显著增加。钾肥偏生产力随着钾肥用量的提高而显著降低,但钾肥农学利用率、生理利用率、表观利用率以及收获指数均在施钾量为90 kg/hm^(2)时达到最大,随后逐渐减小。经济效益分析表明施钾量为120 kg/hm^(2)时产投比和净收入达到最大,再继续增加钾肥用量经济效益反而会降低,结合线性加平台方程拟合结果该地区实现经济效益最大化的推荐施钾量为114.6 kg/hm^(2)。综上,合理施用钾肥能够显著提升油菜生物量、氮、磷和钾等养分积累量,提升株高、一级分枝数和角果数,实现增产和最大经济效益。

贮藏时间对细柱西番莲种子萌发特性及幼苗特征的影响

繁殖材料是深入研究与开发某个植物资源的基础,为了解细柱西番莲种子萌发特性、活力变化以及幼苗的生长状况,以采收后分别常温贮藏1个月、2个月、4个月和5个月的细柱西番莲Passiflora suberosa种子为试材,测定比较种子发芽时间、发芽率、发芽势、子叶纵横径、第一片真叶纵横径以及幼苗生物量。结果表明,在常温条件下,贮藏1个月、2个月、4个月和5个月种子分别在播种后第11天、第12.3天、第13天和第14.7天开始萌发,发芽势分别为22.22%、17.17%、12.22%和10.00%,发芽率分别为96.97%、88.46%、54.44%和21.11%;5株幼苗生物量分别为0.24、0.17、0.16和0.14 g;萌发幼苗子叶纵径分别为1.33、1.26、1.18和1.13 cm,横径分别为0.87、0.83、0.78和0.75 cm;第一片真叶纵径分别为2.78、2.54、2.48和2.39 cm,横径分别为2.73、2.48、2.33和2.25 cm。说明贮藏1个月的细柱西番莲种子发芽最快,发芽势和发芽率最高,萌发幼苗子叶、第一片真叶大小、生物量等也最高。随着贮藏时间延长,其种子发芽率和发芽势均不断下降,幼苗生长指标也下降。

不同杉木第3代种子园良种幼林生长差异

在福建省顺昌埔上国有林场,以7个杉木第3代种子园(南平洋口、南平卫闽、南平建阳、三明将乐、三明永安、漳州西陂、龙岩白砂)种子营建的3~6年生测定林为研究对象,经连续4 a的生长量调查和生物量测定,筛选适合于顺昌种植的杉木第3代种子园良种。结果表明:不同林龄、不同种子园良种测定林生长量、林分蓄积量及生物量具有一定的差异,综合林木生长量及林分生物量指标,筛选出三明将乐、南平建阳、南平卫闽的第3代杉木种子园良种为较适合顺昌种植,其6年生树高生长量依次为3.25、2.83、3.42 m,胸径生长量依次为4.57、4.30、4.85 cm,林分蓄积量依次为71.35、63.01、69.51 m^(3)·hm^(-2),地上部分总生物量依次为94.74、93.91、90.82 t·hm^(-2)。

Genotypic Differences in Growth and Physiological Responses to Transplanting and Direct Seeding Cultivation in Rice

The field experiments were conducted to investigate the growth and physiological responses of six super hybrid rice combinations to two planting methods, transplanting （TP） and direct seeding （DS） during 2006-2007 and 2007-2008. The 1000-grain weight and number of tillers per plant at the early growth stage, the maximum quantum yield of PSII （Fv/Fm） and transpiration rate （Tr） were higher in DS plants than in TP ones, whereas the grain yield, number of panicles per square meter, seed setting rate, net photosynthetic rate （Po） and stomatal conductance were lower in DS plants. However, little difference was detected in number of grains per panicle, stem （shoot） and leaf weight between the combinations in the two planting methods. The responses of plant growth and physiological traits to planting method differed greatly among the six combinations. In both planting methods, Chouyou 58 and Yongyou 6 had the highest and lowest panicle biomass and Pn, respectively. The higher yield of Chunyou 58 was associated with more numbers of panicles per square meter and grains per panicle in both planting methods. The results indicate that lower grain yield in DS relative to TP is attributed to more excessive tillers at the early stage, lower leaf biomass and photosynthetic rate at the late stage.

Effect of mixture sowing on biomass allocation in the artificially-planted pastures, Southeastern Tibetan

Artificial planting is an important measure to promote the restoration of degraded grassland and protect the ecological environment. The objectives of the current study were to investigate the allocation pattern between aboveground biomass(AGB) and belowground biomass(BGB) in different seeding types of artificially-planted pastures. We explored the variation in biomass and the relationship between above-and belowground biomass in four artificiallyplanted pastures with one species from Elymus nutans Griseb(EN, perennial), Elymus sibiricus Linn(ES, perennial), Medicago sativa Linn(MS, perennial), and Avena sativa Linn(AS, annual) and in six artificially-planted communities with mixtures of two species by seeding ratio 1:1 from the abovementioned grasses(EN + AS, MS + AS, EN + ES, MS + EN, MS + ES, AS + ES) in 2015 and 2016. The results showed that E. nutans is the most productive species with the highest biomass production among the single crops. MS + ES was the most productive group in 2015, while the group with the highest biomass production changed to AS + ES in 2016. AGB was positively correlated to BGB in the surface soil layer in the first year, but positively related to BGB in the subsoil layer in the second year. In the early stageof artificial grassland succession, plants allocated more biomass to aboveground parts, with a root to shoot(R/S) ratio of 1.98. The slope of the log-log relationship between AGB and BGB was 1.07 in 2016, which is consistent with the isometric theory. Different sowing patterns strongly affected the accumulation and allocation of biomass in artificiallyplanted grassland, E. sibiricus was the suitable plant in the alpine regions, which will be conducive to understanding vegetation restoration and plant interactions in the future.

Variation in seed and seedling traits and their relations to geo-climatic factors among populations in Yunnan Pine(Pinus yunnanensis)

Differences in seed germination and seedling growth among populations of Pinus yunnanensis Franch. were quantified to provide information for use in the regeneration, reforestation, and improvement of this species. Seed germination and seedling growth traits at the nursery stage were investigated at the population level. We evaluated relationships between pairs of measured traits as well as the association between measured traits and geo- climatic variables including longitude, latitude, elevation, temperature and precipitation. Seedling growth showed significant differences although a low magnitude of variation was found in the seed germination traits among the populations. Some populations with strong and stable growth （e.g., the Baoshan population） may be selected as superior seed sources for regeneration and reforestation. Germination percentage was negatively correlated with elevation, and positively with precipitation. In addition, germination index, vigor index and seedling height were positively correlated with precipitation. Seed germination index, cotyledon number and length, and seedling diameter were significantly and positively correlated with seed weight. Strong correlations between pairs of traits will be helpful in early evaluations for the selection of certain prominent traits.

西北地区制种玉米产量及氮素吸收对供氮水平的响应

【目的】针对我国制种玉米氮素吸收与累积规律不明确的问题,研究制种玉米生物量累积、产量形成和氮素吸收对供氮水平的响应,旨在为制种玉米高产高效绿色生产提供理论依据。【方法】以大面积制种的品种组合为试验材料,于2019-2020年开展田间定位试验。采用完全随机区组设计,共设置4个供氮水平,分别为只施底肥对照(CK)、168 kg N·hm^(-2)、240 kg N·hm^(-2)和320 kg N·hm^(-2),研究不同供氮水平对制种玉米父母本生物量、杂交种产量和氮素吸收累积的影响。【结果】制种玉米父母本生物量累积随供氮水平的提高而提高,产量随供氮水平的提高先增加后保持稳定,N240处理同时实现了较高的产量、氮肥利用率和籽粒氮浓度,两年结果较为一致。N168处理在试验第2年达到较高产量,但氮浓度低于N240处理。母本秸秆及父本整株氮浓度均为高氮处理高于低氮处理;灌浆期母本实现最大生物量的临界氮浓度为15.08 g·kg-1,收获期母本生物量与氮浓度呈线性相关。各追施氮肥处理的花后生物量两年间均大于花前,且随供氮水平的提高而提高,花后氮吸收比例随供氮水平的变化规律与生物量一致。N320处理与N240处理的产量水平、生物量累积和氮吸收均无显著差异。综合考虑产量与制种玉米品质时,N240可作为该区域制种玉米生产的推荐施氮量。【结论】优化施氮通过调控制种玉米父母本花前花后氮吸收比例实现增产增效。本研究揭示了优化施氮量稳定花前氮吸收,保障花后氮供应是制种玉米高产高效的关键,为制种玉米绿色生产提供了理论依据。

Ultraviolet-B Radiation Alters Soybean Growth and Seed Quality

Research on the effects of ultraviolet-B (UV-B) radiation on soybean seed quality is limited. The objective of this study was to quantify UV-B doses, 0, 5, 10 & 15 kJ•m–2•d–1, on soybean growth and seed quality. The experiment was conducted in the Soil-Plant-Atmosphere-Research (SPAR) facility. Chambers located at the R.R. Foil Plant Science Research Facility of Mississippi State University, Mississippi, USA, were used. Each SPAR chamber consists of a steel soil bin to accommodate the root system, a Plexiglas chamber to accommodate plant canopy and a heating, and cooling system connected to air ducts that pass conditioned air to cause leaf flutter through the plant canopy. The SPAR units, supported by an environmental monitoring and control systems, are networked to provide automatic acquisition and storage of the data, monitored every 10 seconds throughout the day and night. Soybean cultivar Pioneer 93Y92 (maturity group IV, Roundup Ready) was used in the study. The desired UV-B radiation was supplied by square-wave UV-B supplementation systems under near ambient PAR and delivered to plants for eight hours, each day, from 08:00 to 16:00 h by eight fluorescent UV-313 lamps. The results showed that increased UV-B did not influence many of the growth parameters because the treatments were imposed at mid-fruiting period. Seed quality parameters that are important for seed industry and human and animal nutrition were all affected by UV-B. Protein and palmitic and oleic acids declined linearly, while oil and linoleic and linolenic acid contents increased with increased UV-B. Sucrose, stachyose, and stearic acid contents showed quadratic trends, increased to about 4 - 5 kJ of UV-B and declined at higher doses. Thus, both current and projected UV-B radiation levels can modify soybean growth and seed quality. The functional algorithms developed in this study could be useful to develop UV-B- specific sub-models for soybean farm management and in policy decision areas.

Effect of different water supply on morphology, growth and physiological characteristics of Salix psammophila seedlings in Maowusu sandland, China

Response pattern was investigated for seedlings of Salix psammophila, a dominant shrub in Maowusu sandland, to the simulated precipitation change by artificially controlling water supply at four levels. The growth characters, in terms of plant height, stem diameter, total branch number, total leaf number and area, total bifurcation ratio, total branch lenght and branch number, branch lenght, leaf number and leaf area of each branch order, and leaf, branch and root biomass significantly increased when water supply increased. That water supply had significant effect on biomass allocation showed different investment pattern of biomass resource of the seedlings grown under different water supply treatments. Stomatal density of abaxial leaf surface decreased, and stomatal apparatus length and width of adaxial and abaxial leaf surface increased with the increase of water supply, while Stomatal density of adaxial leaf surface was not affected by water supply. Water supply obviously affected the diumal changes of photosynthetic rate, and the photosynthetic rate of the seedlings showed strongly midday depression grown under the 157.5 mm water supply, but not grown under higher water supply. Additionally the assimilation-light response curves and flourescence efficiency more showed that water supply improve photosynthesis capacity. Finally, S. psammophila seedlings stood out by their slow growth and relatively high investments in root growth in order to reduce tissue losing rate and consumption of water resource for keeping water balance under water stress. The seedlings that grown under rich water supply did by their fast growth and relatively high investments in branch and leaf growth in order to improve the power of capturing light energy for higher photosynthesis.

刈割对一年生短生草雀麦生长和繁殖的影响

雀麦(Bromusjaponicas)为一年生短生草,是准噶尔荒漠早春优质牧草。对雀麦自然种群物候进行观测,在拔节期设置两个刈割高度,分别为2.5 cm(矮,S)和7.6 cm(高,T),研究不同刈割强度对雀麦植物生长和繁殖的影响。结果表明:(1)刈割降低了植株高度、旗叶长度、生物量和总生物量;T处理和S处理植株的高度分别比对照降低了28.2%和40.1%,生物量比对照降低了29.9%和60.6%。(2)刈割显著降低了雀麦果穗的长度、小穂的数目、果实数目和果实的重量;随着刈割强度的增加,雀麦果穗的长度、果实数目和果实重量显著降低;T处理和S处理果穗的长度分别比对照降低了29.1%和41.6%、果实数目分别降低了54.5%和71.7%。(3)刈割后雀麦的果实重、果实数目、生物量和总生物量的补偿指数均显著小于1,补偿生长模式为不足补偿;S处理的补偿生长能力显著小于T处理。研究结果对于揭示短命植物的补偿生长模式以及雀麦资源的合理利用提供科学数据。

响应面法优化鹿茸菇液体菌种发酵配方

【目的】以提高鹿茸菇液体菌种菌丝生物量为目的,通过优化液体菌种发酵配方,制备优良液体菌种,推动鹿茸菇工厂化生产快速发展。【方法】以鹿茸菇为研究材料,采用摇瓶培养方式,通过单因素设计分析6种碳源、8种氮源、10种金属离子对鹿茸菇菌丝生长的影响。采用Box-Behnken响应面法进一步优化单因素筛选出的碳源、氮源与金属离子,比较分析液体菌种与固体菌种应用于鹿茸菇生产的优劣性。【结果】适合鹿茸菇生长的营养要素分别为全麦粉、花生饼粉、KH2PO4与MgSO4·7H2O,营养要素间的最优配方为全麦粉47 g·L^(-1)、花生饼粉22g·L^(-1)、KH2PO42.00 g·L^(-1)、MgSO4·7H2O 2.00 g·L^(-1),当发酵培养至第8 d时,菌丝生物量达到最大值(32.81±1.10g·L^(-1)),以优化配方制备的鹿茸菇液体菌种菌丝生物量较初始配方提高了7.34倍。在生产试验中液体菌种较固体菌种,制种时间缩短48 d,菌丝萌发时间缩短2 d,单袋产量提高15.47%。【结论】本研究研发的液体菌种发酵配方可获得高质量的生产用种,以液体发酵方式制备鹿茸菇生产用种适合鹿茸菇工厂化生产。

玉米种子定向种植对根系生长的影响

为探究种子定向种植对根系生长的影响,本研究以夏玉米品种‘郑单958’为对象,于2020—2021年通过发芽纸试验、室外桶栽和田间试验研究了两种灌溉条件下(充分与干旱)尖端朝上(T-U)、尖端朝下(T-D,对照)、胚面朝上(E-U)和胚面朝下(E-D)4个种子定向对玉米根系和地上部分生长的影响。结果表明:在水分充足条件下,EU处理的玉米比其他处理的根系发达(深层根重密度平均高5%、平均根重密度平均高5%、深层根长密度平均高48%、平均根长密度平均高10%),且能够利用较多的土壤水分(18%);同时相比于其他处理,E-U处理的植株具有较宽的叶片生长方位角(35%)、较高的叶面积指数(7%)和地上生物量(3%),最终产量比其他处理平均高8%。相关分析表明,产量与地上部生物量、穗数和收获指数直接相关,与深层根重密度间接相关。干旱条件下,与其他处理相比,T-D处理的玉米种子根生长速率快(36%)、根角度窄(43%)、深层根重密度最高(19%)以及吸收较多的土壤水分(5%),导致即使在叶片生长方位角较窄的情况下仍能获得较高的地上生物量(6%)。总之,在水分充足条件下,玉米地上部与根系分布共同促进了胚面朝向种植处理的产量增长;而在干旱条件下,尖端朝下种植处理的干物质积累主要受根系分布的影响。本研究表明通过调整玉米种子播种方向既可以调控根系分布,又可以改善叶片生长方位角和冠层覆盖度,未来或许可以进一步提高玉米在干旱胁迫下的生物量和产量。

一株耐铀菌株的鉴定及其促生特性研究

从退役铀矿区土壤中筛选获得耐铀促生菌株,为铀污染土壤的微生物-植物联合修复技术提供优良菌种资源,以解决退役铀矿区污染治理问题。梯度稀释某退役铀矿区污染土壤,涂布含铀培养基,分离筛选出一株具有耐铀性能菌株B2。通过形态学观察、生理生化实验及16S rDNA序列比较分析,对其进行初步鉴定。采用分光光度法测定菌株在铀胁迫下的生长曲线和培养基铀含量,分析其耐铀能力和铀吸附或吸收能力。通过平板法测定其固氮、解磷、产纤维素酶、合成铁载体能力。用Salkowski比色法测定其产吲哚乙酸(3-indole acetic acid,IAA)能力及产量。通过种子萌发和盆栽实验,验证该菌株的促生能力。综合形态观察结果、生理生化特征和基于16S rDNA序列的进化分析,确定菌株B2为微枝形杆菌属细菌(Microvirga makkahensis sp.),在铀浓度为0-400 mg/L时,其生长曲线符合S型生长曲线模型,当铀浓度达到600 mg/L后生长受抑制,其对培养基中的铀无吸附或吸收作用。菌株B2具有固氮、解磷、产纤维素酶、合成铁载体和产IAA的促生特性,培养48 h后IAA产量可达到24.39μg/mL。菌株B2可显著提高上海青(Brassica chinensis L.)种子的发芽率,促进幼苗的生长发育,显著增加上海青生物量。菌株B2为一株具有产IAA等促生能力、耐铀的微枝形杆菌属细菌,能有效促进上海青种子萌发和幼苗生长,可作为微生物-植物联合修复铀污染土壤的候选菌株。

云贵高原区青贮玉米不同播种方式的饲草产量和效益

以大田生产试验数据为依据,分析了不同播种方案对青贮玉米单株生长、饲草产量和经济效益的影响。研究结果表明:云贵高原区青贮玉米生产时,采用农机穴播,播种量45kg/hm^(2),种植密度8~9万株/hm^(2)时,饲草产量和效益最高。与籽实玉米生产相比,青贮玉米不仅有更高的经济效益,而且在抵制自然灾害导致的减产风险方面也具有一定优势。但青贮玉米生产在收贮、运输及利用等方面与籽实玉米生产相比存在一定局限性。云贵高原区玉米改籽实为青贮原料生产时,其规模应与当地养牛、养羊业的发展规模相适应。

酸和铝胁迫对苦荞种子萌发与幼苗生长的影响

以苦荞品种西荞1号为研究材料,设置不同pH值和铝离子浓度的培养液,研究酸和铝胁迫对苦荞种子萌发和幼苗生长的影响.结果表明,随着pH值升高,苦荞种子的发芽势呈现上升趋势,但发芽率受pH值影响较小;相较于其他pH值,幼苗在pH值为3.5的溶液中生长发育受到显著抑制(P<0.05).与对照组相比,低浓度的铝离子溶液可以促进苦荞种子的发芽势,高浓度的铝离子溶液对发芽势无显著影响;随着铝离子浓度增加,对幼苗根部生长的抑制作用逐渐增强,对地上部生长的影响不显著.以上结果将为深入研究苦荞对酸和铝胁迫的生理机制提供参考.

滇青冈苗木生长对采种母树外源激素和微波处理的响应

采用U^(*)_(12)(12^(10))的变形U^(*)_(12)(4^(10))均匀设计,开展采种母树、微波辐射时间和不同浓度外源激素溶液浸种的苗木培育试验。结果表明:苗龄274 d时,处理组合的平均地径为2.57~3.28 mm,苗高和主根长分别为13.8~19.9 cm和17.0~25.8 cm,根、干、叶和全株生物量分别为0.31~0.83、0.27~0.63、0.60~1.40、1.18~2.87 g/株,苗木质量指数为0.17~0.38。处理组合间除干的含水率外,所有指标均呈显著或极显著的差异。叶是构成滇青冈苗木生物量的重要器官,约占全株的1/2;该树种苗木属含水量较高的类型,其占苗木生物量鲜重约1/2。采种母树是影响滇青冈苗木生长和生物量的主导因子,母树间苗木生长和生物量具有极显著的差异。微波辐射5 s后,采用1.5 g/L和0.35 g/L的GA_(3)和IAA溶液浸种1^(#)母树种子的苗木综合质量最优。滇青冈苗木生长和生物量积累主要受遗传影响,其壮苗培育需要在选择采种母树基础上开展。外源激素浸种在良种基础上,促进滇青冈苗木生长和生物量积累。

割草干扰对典型草原土壤种子库种子数量与组成的影响 Ⅳ群落生物量的组成与种子数量组成的比较

对典型草原群落生物量的组成与种子数量的组成进行了比较研究 ,主要结果如下 :在割草干扰下 ,割一年休一年和一年割一次的群落生物量分别较对照下降了 1 5 .5 8%和 2 5 .31 % ;具有生命力的种子数量分别较对照下降了 1 1 .35 %和 2 7.33% .种群相对生物量与相对种子数量没有一致的关系 ,表现为 5种形式 ,即生物量较高而种子数量较低 ;生物量较低而种子数量较高 ;生物量与种子数量相近 ;有生物量而无种子数量和无生物量而有种子数量 .不同科植物生物量与种子数量有一定的差异 .禾本科植物生物量较高 ,而种子数量较低 ;菊科植物生物量较低 ,而种子数量较高 ,豆科植物生物量一般高于种子数量 ;其余科植物均有各自的特点 .不同生活型植物生物量与种子数量也有差异 .多年生草本植物生物量最高 ,而种子数量较低 ;一年生、二年生和一、二年生草本植物生物量较低 ,而种子数量占总量的一半以上 ;

直播水稻物质生产特点及其高产调控技术研究

以粳稻 95 16为材料 ,对上海地区直播单季水稻物质生产特点进行了分析研究。结果表明 :(1)生物产量与经济产量相关密切 ,抽穗前干物质生产量与谷物产量呈二次曲线相关 ,抽穗后干物质生产量与谷物产量呈极显著线性正相关。 (2 )抽穗期干物重与单位面积穗数呈显著正相关 ;抽穗前各阶段对干物质生产速率的影响 :播种至够苗和够苗至拔节以平均LAI的作用较大 ,拔节至抽穗期以NAR的作用较大。 (3)抽穗后干物质生产量与拔节至抽穗和抽穗至成熟吸N量显著相关 ,与抽穗后单茎干物质生产量显著相关 ,与单位面积颖花量显著相关 ,与抽穗后NAR显著相关 ;抽穗后NAR与抽穗期单茎叶面积、抽穗后叶面积衰退、粒叶比、抽穗期叶片含N率。