Seed Priming Influence on Early Crop Growth,Phenological Development and Yield Performance of Linola (Linum usitatissimum L.)

Reduced early crop growth and limited branching are amongst yield limiting factors of linola. Field response of seed priming treatments viz. 50 mmol L⁻¹ salicylic acid (SA), 2.2% CaCl₂ and 3.3% moringa leaf extract (MLE) including untreated dry and hydropriming controls was evaluated on early crop growth and yield performance of linola. Osmopriming with CaCl₂ reduced emergence time and produced the highest seedling fresh and dry weights including Chl. a contents. Osmopriming with CaCl₂ reduced crop branching and flowering and maturity times and had the maximum plant height, number of branches, tillers, pods and seeds per pod followed by MLE. Increase in seed weight, biological and seed yields was 9.30, 34.16 and 39.49%, harvest index (4.12%) and oil contents (13.39%) for CaCl₂ osmopriming. Positive relationship between emergence and seedling vigor traits, 100-seed weight, seed yield with maturity time, 100-seed weight and seed yield were found. The study concludes that seed osmopriming with CaCl₂ or MLE can play significant role to improve early crop growth and seed yields of linola.     

播期对饲用玉米生长发育和产量的影响

[目的]研究播期对饲用玉米生长发育和产量的影响,并探索饲用玉米的适宜播期。[方法]以青贮50为试材,对不同播期下饲用玉米的生长发育状况以及乳熟末期和成熟期饲草的产量进行研究。[结果]随着播期的推迟,到达各物候期的日期延后,不同处理相同生育阶段的天数减少,最晚播种的玉米花粒期天数增多。全生育期和抽雄至乳熟末期的天数随播期的推迟而减少,至6月15日播种的玉米天数最少,6月30日播种的玉米天数增多。五叶期玉米的株高随播期的推迟而增高。拔节期以6月15日播种的玉米株高最高,之后至开花吐丝期以5月30日播种的玉米株高最高。抽雄期玉米的单株绿叶数随播期的推迟而减少,灌浆后期至成熟期晚播玉米的单株绿叶数较多。随着播期的推迟,玉米鲜物质积累量、饲草产量和籽粒产量均减少。[结论]在饲用玉米的适宜播期内,播种时间越早越好。     

SA和PEG引发处理对NaCl胁迫下玉米种子萌发及幼苗生长的影响

以冀植五号玉米种子为试验材料,用不同浓度的水杨酸(SA)溶液及聚乙二醇(PEG)溶液对种子进行引发处理。采用标准发芽试验和砂培试验,设3个NaCl浓度(0、100、200 mmol.L-1)模拟盐胁迫,研究SA和PEG引发处理对NaCl胁迫下玉米种子萌发及幼苗生长的影响。结果表明:随着NaCl浓度的增加,玉米的发芽率及发芽势下降,幼苗生长受到抑制,干物质积累量减少。同等NaCl浓度胁迫下,用0.25 mmol.L-1SA和15%PEG引发处理玉米种子,和对照相比,提高了种子的发芽势及发芽率,苗高、根长、地上部和根部干重显著增加,最终提高了玉米芽苗期的耐盐性。     

施氮量与栽插苗数对杂交早稻“鄱优364”产量的影响

为探明施氮量和栽插苗数对新型杂交早稻新品种"鄱优364"产量形成的影响,在16.67 cm×20 cm同一栽插规格下,探讨其不同施氮量(0,120,150,180,210 kg/hm25个水平)和栽插苗数(2,3,4根/穴3个水平)下产量及其构成等指标的差异性。结果表明:施氮量对产量、有效穗数、每穗粒数、结实率和千粒质量具有极显著影响,纯氮为210 kg/hm2时,增穗、增产效果均不明显,反而降低了每穗粒数和结实率;随着栽插苗数增加,产量和有效穗数也随之增加,每穗粒数随之降低,结实率和千粒质量呈降低趋势;施氮量和栽插苗数互作对产量、每穗粒数、结实率和千粒质量有极显著影响,随着施氮量和栽插苗数的增加,产量增加,然而每穗粒数、结实率和千粒质量随着施氮量和栽插苗数的增加而减少,对有效穗数无显著影响。施氮量180 kg/hm2结合栽插苗数4根/穴有利于"鄱优364"增产。     

Changes in Nutrient-Homeostasis and Reserves Metabolism During Rice Seed Priming： Consequences for Seedling Emergence and Growth

In this study influence of different seed priming treatments on the nutrient-homeostasis and reserve metabolism during seedling emergence and growth of rice were determined. Seed priming treatments included pre-germination, hydropriming for 48 h, osmohardening with KCl and CaCl2, ascorbate priming and hardening. All treatments shortened the emergence time and enhanced the energy and index of seedling emergence. Seedlings from primed seeds had greater length, number of roots and fresh and dry mass than control. Among the treatments, CaCl2, ascorbate and KCl proved better in enhancing emergence and seedling growth. Seed priming changed the pattern of N and Ca^2＋ homeostasis both of the seeds and seedlings, which were associated to enhancing s-amylase activity and reducing sugars content. Positive correlations of seedling attributes with nutrient content suggested that as a result of seed priming, most of N and Ca^2＋ were partitioned to embryo, which enhanced seedling emergence and subsequent growth of rice seedlings.     

不同种植密度对玉米新品种豫单998产量的影响

为给玉米新品种豫单998在生产上采用合理的种植密度提供理论依据,对不同种植密度下豫单998群体指标与产量及产量构成因素的关系进行了试验研究。结果表明:不同密度间单株叶面积,叶、茎干物质积累差异不显著;不同密度处理叶片光合速率均呈下降趋势,且呈显著差异;5 000株/667m2产量最高(786.6 kg/667m2),豫单998群体调控能力强,是耐密型玉米品种。     

Increasing photosynthetic performance and post-silking N uptake by moderate decreasing leaf source of maize under high planting density

To date,little attention has been paid to the effects of leaf source reduction on photosynthetic matter production,root function and post-silking N uptake characteristics at different planting densities.In a 2-year field experiment,Xianyu 335,a widely released hybrid in China,was planted at 60 000 plants ha~(–1 )(conventional planting density,CD) and 90 000 plants ha~(–1) (high planting density,HD),respectively.Until all the filaments protruded from the ear,at which point the plants were subjected to the removal of 1/2 (T1),1/3 (T2) and 1/4 (T3) each leaf length per plant,no leaf removal served as the control(CK).We evaluated the leaf source reduction on canopy photosynthetic matter production and N accumulation of different planting densities.Under CD,decreasing leaf source markedly decreased photosynthetic rate (P_n),effective quantum yield of photosystem II (ΦPSII) and the maximal efficiency of photosystem II photochemistry (F_v/F_m) at grain filling stage,reduced post-silking dry matter accumulation,harvest index (HI),and the yield.Compared with the CK,the 2-year average yields of T1,T2 and T3 treatments decreased by 35.4,23.8 and 8.3%,respectively.Meanwhile,decreasing leaf source reduced the root bleeding sap intensity,the content of soluble sugar in the bleeding sap,post-silking N uptake,and N accumulation in grain.The grain N accumulation in T1,T2 and T3 decreased by 26.7,16.5 and 12.8% compared with CK,respectively.Under HD,compared to other treatments,excising T3 markedly improved the leaf P_n,ΦPSII and F_v/F_m at late-grain filling stage,increased the post-silking dry matter accumulation,HI and the grain yield.The yield of T3 was 9.2,35.7 and 20.1% higher than that of CK,T1 and T2 on average,respectively.The T3 treatment also increased the root bleeding sap intensity,the content of soluble sugar in the bleeding sap and post-silking N uptake and N accumulation in grain.Compared with CK,T1 and T2 treatments,the grain N accumulation in T3 increased by 13.1,40.9 and 25.2% on average,respectively.In addition,under the same source reduction treatment,the maize yield of HD was significantly higher than that of CD.Therefore,planting density should be increased in maize production for higher grain yield.Under HD,moderate decreasing leaf source improved photosynthetic performance and increased the post-silking dry matter accumulation and HI,and thus the grain yield.In addition,the improvement of photosynthetic performance improved the root function and promoted postsilking N uptake,which led to the increase of N accumulation in grain.     

不同耕作方法条件下玉米抗御低温冷害的研究(英文)

[Objective] Aiming at chilling damage of maize in lowland of western Liaoning, the powerful evidences of resisting chilling damage of maize were provided from tillage method perspective.[Method] The depths of plough layers, sunshine effects in seedling stage, resistances to frost damage, microclimatic effects such as soil moisture, root system in filling stage, growth periods and grain weights of maize planted on ridge and in furrow were comparatively observed. The random arrangement was adopted in comparative observation with 4 replications.[Result] The daily mean ground temperature and effective accumulated temperature of plough layer of maize planted on ridge were relatively high. In addition, the seedling stage and mature stage of maize planted on ridge were in advance, the soil moisture, root growth and seed plumpness of maize planted on ridge were good. [Conclusion] The ridge planting in lowland of western Liaoning could improve in 0-20 cm plough layer where root grew, besides that this method could also improve maize growth and development.     

不同耕作方法条件下玉米抗御低温冷害的研究

[目的]针对辽西地区平洼地玉米受低温冷害问题,从耕作技术的角度为平洼地玉米抗御低温冷害提供了有力的理论依据。[方法]对种垄台与种垄沟玉米的耕作层温度、出苗期日照效应、抗御春秋霜低温冷害、土壤墒情等微气候效应以及玉米灌浆期根系生长状况、生育期及粒重进行对比观测,观测采用随机排列法,同时进行4次重复。[结果]种垄台玉米苗期根部所处耕作层的日平均地温和有效积温较高,出苗期提前,土壤墒情和玉米根系长势较好,成熟期提前并且籽粒较饱满。[结论]辽西地区平洼地采用种垄台耕作方法可改善玉米苗期根部所处耕作层0~20 cm的小气候条件及其自身的生长发育状况。     

黄土高原旱地矮化苹果定植时期与方式对幼树生长和成花的影响

在渭北黄土高原旱地进行矮化苹果不同定植时期与方式试验研究表明 ,旱原地区改落叶后和萌芽前为早秋 ( 9～ 1 0月 )带叶定植 ,平均单株再生延长新根总量比落叶后、春季和不带叶定植分别高出 8.1倍、5 .4倍、0 .5倍 ,平均单株总生长量分别为落叶后、春季和不带叶定植的 3.2倍、2 .8倍、0 .8倍 ,干径年增长率分别为 2倍、1 .4倍、0 .4倍 ,而且无发病株 ;定植后两年树冠扩展快 ,单株平均总枝量为落叶后、春季和不带叶定植的 8.3倍、3.5倍、0 .7倍 ,第 3年开花株率分别为 30 .2倍、9倍、0 .9倍 ,有利于幼树加速生长 ,提早成形 ,为早果丰产奠定了基础     

秧龄和二次化控对机插水稻毯状育苗综合素质及产量的影响

为了研究烯效唑对移栽水稻影响机制,以两系杂交中籼稻徽两优6号为材料,培育毯秧苗,设置4种秧龄,并于一叶一心期叶面喷施不同浓度的烯效唑进行二次化控处理,考察秧苗素质并跟踪考察栽插质量和产量。结果表明：①随着秧龄的延长,秧苗综合素质下降,与对照20 d秧龄的秧苗素质相比,超秧龄秧苗尤其是严重超秧龄,秧苗素质和秧块状态迅速恶化,表现为株高增加,叶片丙二醛含量增加,发根力和根系活力降低,栽插质量下降,移栽后活棵慢;和20 d秧龄相比,25 d、30 d和35 d秧龄栽插水稻最终产量分别减产1 403.55 kg/hm2、1 995.75 kg/hm2和2 920.95 kg/hm2;②1叶1心期叶面喷施烯效唑二次化控处理可明显提高秧苗素质,与不喷施的对照相比,化控处理的秧苗株高、叶片丙二醛、漏插率、伤秧率、全漂率和翻倒率均明显降低,而百株干重、茎基宽、绿叶数、根数、发根力、根系活力、出苗率、株高整齐度、根系盘结力等则明显提高;与对照相比,水稻产量增加9%～32%;③不同秧龄对化控强度要求不同,适栽秧龄期,各浓度处理间并无显著差异;而超秧龄初期和中期阶段时烯效唑作用效果随喷施浓度的增加而越发显著。     

皖稻153制种栽插密度对产量的影响研究

[目的]提高制种产量和质量,加快皖稻153品种的推广。[方法]设置每穴栽1、2、3、4苗4个处理,调查各处理的分蘖动态、农艺性状及发芽率。[结果]每穴多苗栽插可以提高有效穗,增加穗粒数,乃至提高制种产量。[结论]综合考虑各种因素,皖稻153的适宜制种栽插密度为2苗/穴。     

种子引发对盐胁迫下玉米种子萌发及幼苗生长的影响

以A060233×D123-42（T,耐盐性较强）和D168-83XA06148（S,耐盐性较弱）两个玉米杂交组合为实验材料,利用80mmol·L^-1NaCl溶液对种子进行引发处理。采用营养液砂培实验,设4个NaCl浓度（0、120、200和250mmol·L^-1）模拟盐胁迫,研究种子引发处理对NaCI胁迫下玉米种子萌发及幼苗生长的影响。结果表明：随着NaCl浓度的增加,无论经引发处理,还是未经引发处理,两个玉米杂交组合的出苗率均下降,幼苗生长均受到抑制,干物质积累量均减少。同等NaCl浓度胁迫下,引发处理与未引发处理相比,种子出苗率增加,促进了苗高和根的生长,叶面积、苗干重、根干重和耐盐指数增加,叶绿素和脯氨酸含量升高,地上部和地下部的K^＋／Na^＋值增加。     

干热河谷牛角瓜育苗技术及幼苗生长节律

 为规范牛角瓜播种繁殖技术并指导生产,从种子处理、播种深度、播种季节三方面,探讨了牛角瓜种子发芽情况及幼苗生长节律。种子发芽试验表明,水浸催芽能提高牛角瓜种子发芽率,最高发芽率为9265%,播种深度为1cm时,发芽率和发芽势最高,方差分析差异分别达极显著（P<001）和显著（P<005）,干种则随深度增加发芽率、萌发率、保存率均增加,这与营养土水分梯度有关;秋播较春播发芽率高,且发芽进程受温度影响小,萌发速率系数和萌发指数显示春播萌发较快,萌发指数差异显著（P<005）。幼苗生长试验表明,牛角瓜幼苗生长可分为慢生长期（0～20d）、快速生长期（20～40d）和慢生长期（60～80d）;播种深度不仅影响发芽率,还影响幼苗生长;春播幼苗受温度影响生长较秋播迅速;叶片数量呈现“增加-减少-增加”趋势,通过叶片自身营养消耗和叶片光合输出影响苗木生长。可见,牛角瓜育苗以晚春或初夏浸泡后浅播为宜。     

增密对我国玉米产量-叶面积指数-光合速率的影响

【目的】探究我国玉米增密过程中地上部群体结构和功能变化,为合理密植提供理论依据。【方法】本文共收集了82篇公开发表的学术论文,获得1 338组产量-密度数据,其中包括1 200组最大叶面积指数（LAI_max）-密度数据,475组穗位叶最大净光合速率（Pn_max）-密度数据。根据播种日期将总样本划分为春玉米和夏玉米2组,综合运用边界线分析和方程拟合等多种方法,对玉米产量、种植密度、光合速率三者之间的关系进行了分析。【结果】（1）我国玉米获得最高产量（11.5 t·hm^-2）时,种植密度为10.0×10⁴plants/hm²。获得最高产量时,春玉米和夏玉米种植密度相近,但春玉米产量较夏玉米高13.0%。（2）当密度达到11.0×10⁴plants/hm²时,LAI_max达到平台值,将不再随密度增加而增大。在LAI_max达到6.4时,可获得最高产量。春玉米LAI_max的平台值较夏玉米高17.6%。用对数函数分析穗位叶Pn_max-密度,穗位叶Pn_max-LAI_max的变化关系时,发现密度和LAI_max增大均导致Pn_max下降,在夏玉米表现尤为显著。（3）分析不同年代品种数据发现,随年代变化产量逐步提高,LAI_max和穗位叶Pn_max不断增大。【结论】增加种植密度是提高玉米产量的重要途径之一。随密度进一步增加,玉米叶片光合特性等发生改变,限制了产量的进一步提高。本研究定量综合分析了玉米产量、种植密度、最大叶面积指数、穗位叶光合速率之间的关系,对构建玉米密植高产高效生产系统具有重要意义。     

不同酸度壳聚糖溶液引发对玉米发芽和幼苗生理特性的影响

研究了酸性(pH5.1)和近中性(pH6.4)壳聚糖溶液引发4个玉米种子材料后,对发芽和幼苗生理特性的影响.结果表明,两种酸度壳聚糖溶液引发都能显著提高4个玉米材料的发芽势,缩短平均发芽时间,增加苗高和叶绿素含量;3种玉米新种子引发后的发芽率与对照无显著差异,但超甜3号陈种子处理低于对照.pH5.1壳聚糖引发处理后,苏玉1号和超甜3号幼苗的POD活性显著提高,MDA含量显著降低;超甜3号陈种子POD活性显著降低,MDA含量处理与对照没有显著差异;玉米幼苗的CAT活性与对照无显著差异.表明,壳聚糖可作为一种新的引发剂用于处理玉米种子,同时两种酸度壳聚糖溶液引发处理间无显著差异,均可提高玉米种子的活力.     

新疆不同耐密型玉米品种光合性能及产量构成特征的研究

[目的]研究滴灌条件下不同耐密型玉米品种光合性能及产量构成特征,为新疆玉米大面积高产栽培提供理论支持.[方法]在新疆气候生态条件下,选择5个不同耐密型玉米品种,在3个种植密度条件下探讨各处理群体冠层光合性能指标、干物质积累及其产量构成的特征.[结果]耐密型品种中单909叶面积指数(LAI)大小适宜,LAI到达峰值的时间较早,抽雄前与灌浆后LAI变化速率较小;花后光合势的比例、净同化率较高,粒叶比较大,总干物质和生殖器官干物质积累时间较长,高密度下收获株穗数和产量较高;稀植大穗型品种中单808虽然叶面积指数、光合势均较高、植株干物质积累量大,但花后光合势所占比例、净同化率和粒叶比均随密度增加显著降低.在高密度条件下(13.5×104株/hm2),群体收获穗数及穗粒重显著降低,严重制约了产量的进一步提高.[结论]在新疆干旱气候生态条件下,利用膜下滴灌技术,充分利用丰富的光照资源优势,选用冠层光合性能强的耐密型玉米品种,通过增加种植密度,挖掘品种自身的高产潜力,最终实现大面积丰产稳产.     

苗期低温胁迫对玉米生长发育及产量的影响

通过对玉米苗期进行不同低温胁迫试验,研究两个玉米品种（丹玉39、丹玉42）对苗期低温的响应。结果表明,苗期低温胁迫后,两个玉米品种的生长发育及产量存在明显的差异：（1）三叶期—七叶期,低温胁迫处理阶段玉米生长均受到抑制,对丹玉39的影响大于丹玉42;（2）拔节期—乳熟期,经过苗期低温胁迫后,丹玉39后期叶面积逐渐接近并最终在乳熟期达到对照正常水平,而丹玉42的后期恢复能力较差;（3）丹玉42低温胁迫后呈现苗期天数增加、穗期天数减少的趋势,丹玉39无明显变化;（4）成熟后的丹玉42果穗大小、茎杆重、籽粒重和百粒重均小于对照,生物量及产量显著下降,而丹玉39的果穗性状、生物量及产量受影响较小。     

干旱条件下玉米叶面积变化及地上干物质积累与分配的研究

在干旱地区自然降水条件下,对4个大面积推广的玉米杂交种进行不同干旱处理,测定其叶面积及干物质积累与分配的变化。结果表明,拔节到灌浆初期是干旱影响玉米叶片生长及叶片功能发挥的重要时期;干旱影响玉米大喇叭口期至乳熟期的干物质积累,使玉米最大干物质积累时期推迟到开花期至乳熟期;苞叶和茎鞘中的干物质向籽粒的转运率较高,茎鞘中积累的干物质对玉米籽粒的贡献率最高。干旱条件下,玉米在大喇叭口期至乳熟期具有较大的叶面积、较强的光合能力和较长的光合功能期,对乳熟期获取较大的生物产量和提高籽粒产量都有很大的作用,玉米的耐旱性相应增强。     

玉米对持续干旱的反应及红壤干旱阈值

 【目的】研究玉米对红壤干旱的反应以及红壤干旱程度定量表达和干旱阈值。【方法】在田间小区遮雨条件下种植夏玉米，设置连续干旱12～36 d等6个处理，用FDR水分仪每日测量0～60 cm不同土层含水量，定期观测玉米植株生长状况和气孔导度，收割后考种。【结果】玉米的株高、茎粗、气孔导度、根系数量等测量值在不同干旱天数之后显著降低，在不同土壤干旱程度下出现阈值反应，连续干旱25 d之后，玉米籽粒产量显著降低5%。干旱过程中，土层贮水量和累积相对失水量之间的关系可以用对数线性方程表示，将方程的斜率转换为取值在［0，1］区间的指数D，可以定量表达土壤干旱程度。【结论】D值既可以表示土壤干旱状况又可以表示作物受旱程度，玉米拔节－抽穗期红壤干旱程度D达到0.55则产量显著降低。