稻秸还田与播种方式影响小麦出苗及产量的大田试验研究

为了研究水稻秸秆还田与播种方式对小麦出苗及籽粒产量的影响,通过田间大区试验,分析了稻秸机械全量还田与不同播种方式对小麦出苗率、出苗均匀性及产量性状的影响。结果显示,稻秸不还田条件下,机械条播的出苗率显著低于机械匀播和人工撒播,机械条播、机械匀播和人工撒播的出苗率分别为51.84%、90.89%和88.87%;人工撒播的出苗均匀性差于机械条播和机械匀播,3 种播种方式的出苗变异系数分别为0.49、0.26 和0.23。稻秸机械全量还田条件下,不同播种方式处理的出苗率和出苗均匀性都有所降低,其中机械条播的下降幅度较大,出苗率降低了36.54%。小麦出苗率和出苗均匀性通过影响穗数、穗粒数、千粒重而影响籽粒产量,无论稻秸是否还田,机械匀播的产量均高于其余两种播种方式,稻秸不还田和全量还田条件下的产量分别为6091.34 kg/hm2和6476.20 kg/hm2。因此,在稻秸还田小麦生产中,推荐采用机械匀播的播种方式,不仅能提高小麦的田间出苗率,而且能保持较好的出苗均匀性,有利于获得较高的籽粒产量。     

组合播种方式对小麦群体及产量形成的影响

为了提高玉米秸秆还田后小麦播种质量,为广大麦玉轮作区小麦生产提供技术支撑,通过采用将不同小麦播种方式进行组合的研究方法,对小麦群体发育及产量结构进行分析。结果表明：在播量相同情况下,“撒播+宽幅播”的组合播种方式可以显著降低田间缺苗断垄单元的分布,提高田间群体生物量积累。通过试验研究得出：在适宜播量条件下,“撒播+宽幅播”的组合播种播量比例以1:2为宜。‘舜麦1718’在播量为135.0 kg/hm²时,播量比例为1:2的“撒播+宽幅播”的组合播种方式,产量显著高于传统条播、宽幅播及撒播等单一播种方式。     

稻秸还田下耕作与播种方式对小麦出苗及产量的影响

为了研究稻秸还田下耕作与播种方式对小麦出苗及产量的影响,通过大区试验,分析了稻秸全量还田下不同耕作与播种方式对小麦出苗率、出苗均匀性及产量性状的影响。结果显示,相同的播种方式下,浅耕处理小麦出苗率高于免耕处理,但出苗均匀性差于后者;相同的耕作方式下,播种方式对小麦出苗率和出苗均匀性的影响差异较大,其中,机械匀播方式下小麦出苗率最高,出苗均匀性最好;小麦出苗率和出苗均匀性通过影响穗数、穗粒数、千粒重而影响籽粒产量,同一耕作方式下机械匀播小麦籽粒产量均高于其余2种播种方式,免耕和浅耕下机械匀播小麦产量分别达6484.35 kg/hm~2和6476.20 kg/hm~2。因此,稻秸全量还田条件下,建议采用免耕机械匀播方式,能有效改善小麦田间出苗情况,进而获得较高的籽粒产量。     

播种方式对不同品种小麦产量和品质的影响

研究不同播种方式对不同品种小麦产量和品质的影响,为小麦高产高效栽培提供参考。采用二因素随机区组设计,播种方式为匀播（A1）和常规条播（A2）,小麦品种为衡观35(B1)、邯6172(B2)、轮选103(B3)和石麦25(B4)。结果表明,2种播种方式对植株性状影响差异显著,条播的株高和穗粒数均显著高于匀播,匀播的产量、穗数和千粒重均显著高于条播,其中匀播处理的产量比条播提高4.42%。播种方式对小麦的容重、面筋指数、出粉率和14%吸水率有显著影响,匀播处理的小麦出粉率比条播高2.02个百分点。条播处理下石麦25的产量最高,衡观35的磨粉品质较好;匀播处理下衡观35、邯6172和轮选103的产量均较高,邯6172的粉质指标较好。     

播种方式和播量对干旱区旱地小麦土壤水分利用及产量的影响

为明确旱地小麦播种方式和播量对土壤蓄水量及产量的影响,以播种方式为主区,设常规条播(C1)、起垄沟播(C2)、宽幅播种(C3)3个播种方式;播量为副区,设180(D1)、240(D2)、300(D3)、360(D4)kg/hm² 4个播量,研究其对旱地小麦土壤蓄水量、水分利用效率和产量的影响。结果表明,同一个播种方式下,播量240和300 kg/hm²较其他播量处理均增加拔节期和开花期土壤蓄水量、开花―成熟阶段土壤耗水量,提高水分利用效率,优化产量构成因素,提高产量,且这2个播量处理间无显著差异。宽幅播种和起垄沟播较常规条播均显著增加拔节期和开花期土壤蓄水量均值,增加开花―成熟阶段土壤耗水量及其所占比例均值,提高水分利用效率和产量均值,尤其是宽幅播种表现更为突出。宽幅播种较常规条播和起垄沟播水分利用效率分别提高23%和3%,产量分别提高25%和3%。由此得出,在干旱区,旱作小麦采用宽幅播种和播量240～300 kg/hm²组合,利于小麦营养生长期土壤水分蓄积,开花后增加土壤水分消耗,利于增加穗数,提高产量。     

小麦宽幅匀播技术氮、磷、钾施肥效果及推荐施肥量研究

为了探讨宽幅匀播小麦的肥料高效利用和土壤养分吸收的机理,采用多点田间小区试验,应用“3414”田间肥料试验设计方法,分析在不同肥力水平下小麦宽幅匀播技术氮、磷、钾的施肥效果和推荐用量。结果得出,宽幅匀播小麦氮、磷、钾养分利用率随施肥水平提高而显著降低,随土壤肥力增加呈先增高后降低,从高到低依次为：中肥力＞较低肥力＞低肥力＞较高肥力＞高肥力。随土壤肥力由低到高增加,宽幅匀播小麦最佳施肥效益的推荐施肥量分别是N 107.9~171.8 kg/hm²、P₂O₅ 88.2~112.1 kg/hm²和K₂O 35.4~56.2 kg/hm²,平均分别为：N 138.3 kg/hm²、P₂O₅ 101.4 kg/hm²、K₂O 45.4 kg/hm²,三要素比例为N:P₂O₅:K₂O=1:0.73:0.33。由于不同土壤类型的速效氮磷钾含量有一定差异,小麦宽幅匀播适宜施肥量应因土壤类型而适当调整。     

冬小麦播种技术要点及对比试验研究

小麦是我国种植范围最广的粮食作物，在长城以南种植的小麦被称为冬小麦，当前我国小麦种植以冬小麦为主。小麦播种技术和产量之间存在密切联系，为提高我国小麦产量，研究播种技术极为必要。文章从冬小麦的播种流程入手，分析选种、整地、施肥、播深、镇压造墒、查苗补种以及冬季管理等环节，总结冬小麦播种技术要点，以此为基础，进行常规条播和宽幅精播的对照试验，从个体结构和产量等角度分析宽幅精播的优势，以期为相关农户提供参考。     

播种方式与种植密度互作对大穗型小麦品种产量和氮素利用率的调控效应

为探明实现冬小麦进一步增产增效的调控途径,于2015—2016年和2016—2017年连续两个生长季,选用大穗型品种泰农18,设置2种播种方式(宽幅播种和常规条播)和7个种植密度(130×10~4、200×10~4、270×10~4、340×10~4、410×10~4、480×10~4和550×10~4株hm~(–2)),研究了播种方式与种植密度互作对大穗型小麦品种产量和氮素利用率的调控效应。结果表明,与常规条播相比,宽幅播种配合增密能够有效缓解单位面积穗数增加与单穗粒重降低、氮素吸收效率提高与氮素内在利用效率下降之间的矛盾,通过增加单位面积穗数和氮素吸收效率协同提高籽粒产量和氮素利用率。宽幅播种条件下获得最高产量和氮素利用率的密度为410×10~4株hm~(–2),显著高于常规条播条件下的最优密度(340×10~4株hm~(–2)),且其增产增效幅度亦显著高于常规条播。综上所述,宽幅播种配合合理密植具有进一步协同提高大穗型小麦品种产量和氮素利用率的潜力。在本试验条件下,宽幅播种(苗带宽8～10cm)与410×10~4株hm~(–2)密度相匹配是大穗型小麦品种泰农18获得更高产高效的最优组合。     

冬小麦宽幅播种高产栽培要点分析

小麦宽幅精播技术是一种操作简单、增效明显的高产栽培技术,主要体现在扩大播幅、增加播种行距、精准控制播种量、籽粒播种均匀等方面,可有效改善传统小麦条播缺苗、缺垄、麦田通风等问题,促使小麦健壮生长。从冬小麦宽幅播种前期准备、宽幅播种高产栽培技术要点及田间管理三方面入手,围绕选种、整地、播种、水肥、病虫害等环节介绍播种管理技术,以期为实现冬小麦增量提质提供参考。     

半干旱地区苜蓿旱作播种技术研究

在半干旱区的固原头营采用正交试验对影响苜蓿出苗的主要因子进行研究,应用直观分析法对不同组合条件下苜蓿出苗率和产草量进行分析。结果表明,播量(C)是影响苜蓿出苗率和草产量的主要因素,其次为播深(B)、播种方式(D)和行距(A)。最优组合为:行距25cm、播深2cm、播量19.5kg/hm²、播种方式为条播覆土,该组合条件下基本苗数135万株/hm²,干草产量16.88t/hm²,适于在干旱半干旱地区推广应用。     

腐植酸类肥料浸种及浇灌对燕麦种子萌发和幼苗生长的影响研究

研究腐植酸类肥料浸种及浇灌对燕麦种子萌发和幼苗生长的影响。以燕麦种子为材料,在室内采取标准发芽试验法和生境地土壤培养法,测定腐殖酸类肥料浸种和浇灌后种子萌发及幼苗生长指标。各腐植酸类肥料浸种对种子生活力无显著影响,腐植酸钾显著提高了种子出苗速度(P＜0.05),加速了种子萌发,黄腐酸、腐植钠、腐植酸钠降低了出苗速率和活力指数。从幼苗的生长情况来看,腐植酸钾对幼苗生长量,苗高、根长和种子根的发生有积极的促进作用,虽黄腐酸、腐植酸钠、腐植钠对苗高根长有显著促长作用,但因抑制了种子根的发生,对幼苗的存活和抗逆不利。各腐植酸类肥料浇灌燕麦幼苗后,对幼苗鲜重、根数、根干重、根冠比有促进作用,同时增加了植株的成坨性。腐殖酸钾是燕麦种子播前浸种的最佳腐殖酸类肥料,各腐殖酸类肥料都适合燕麦幼苗田浇灌。     

种子引发对碱胁迫下甜高粱种子萌发及幼苗生长的影响

为研究碱胁迫下种子引发对萌发及幼苗生长的影响,以甜高粱杂交种‘通甜1号’为试验材料,利用500 μmol/L γ-氨基丁酸(GABA)对种子进行引发处理。采用盆栽土培试验,将NaHCO₃:Na₂CO₃=5:1的混合碱胁迫液设3个水平(0、50、100 mmol/L)模拟碱胁迫,研究GABA种子引发处理对碱胁迫下高粱种子萌发状况及幼苗生长的影响。结果表明：随着碱胁迫强度增加,无论是经过引发处理的种子还是未经过引发处理的种子,其吸水量、萌发指数、出苗率和成苗率显著下降,幼苗生长受到限制,生物量积累降低。同等碱胁迫浓度下,经过引发处理的种子与未经过引发处理的种子相比,种子吸水量、萌发指数、胚的生长及幼苗叶面积均显著提高。低浓度碱胁迫条件下,经过引发处理的种子与未经过引发处理的种子相比,幼苗的出苗率和存活率较高、生长至第7天的株高和茎粗及总生物量均显著增加。试验表明,经过引发处理的种子可以不同程度地提高碱胁迫下甜高粱种子萌发指数,缓解碱胁迫对幼苗的不利条件,促进幼苗生长,提高耐碱性。     

Drying and Storage Method to Prolong Seed Viability and Seedling Vigour of Rabi-summer-produced Groundnut

Rabi-summer-produced (dry season, February–May) groundnut ( Arachis hypogaea L.) cv. GG 2 was dried using three different methods, viz. windrow (W), windrow-shade (WS) and DOR (Directorate of Oilseeds Research) methods and stored in polyethylene lined gunny bags with or without desiccant (CaCl₂ or silica gel, 10gkg⁻¹ pods). The seeds were analysed for the retentation of seed viability, seedling vigour, membrane integrity and Held emergence during storage, and crop stand and pod yield after 12 months of storage. The drying and storage method significantly affected the getminability, seedling vigour and field emergence. Both root length and seedling biomass were adversely affected due to windrow drying (W) The quick loss of viability in the W treatment was associated with an increase in electrical conductivity of the seed leachate. The retention of higher seed viabiliry and vigour in the seeds dried by DOR method and stored with CaCl₂ (DOR C) was due to lower drying remperarures and lower pod moisture during the initial storage period. The DOR C method was found to be an effective drying and storage method for retaining acceptable seed viability and vigour till the following rabi-summer sowing of groundnut.     

Effect of Sodium Chloride Salinity on Seedling Emergence in Chickpea

Although laboratory (Petri dish) germination as an estimate of seed viability is a standard practice, it may not give an accurate prediction of seedling emergence in the field, especially when saline irrigation water is used. Experiments were conducted to investigate seedling emergence in two chickpea cultivars (ILC 482 and Barka local) in response to varied salinity levels and sowing depths. Seeds were sown in potted soil at a depth of 2, 4 or 6 cm. The salinity treatments were 4.6, 8.4 and 12.2 dS m^–1. Tap water (0.8 dS m^–1) served as the control. Depth of sowing had a significant effect on seedling emergence. Seeds sown 6 cm deep showed the lowest seedling emergence. Similarly, salinity had an adverse effect on seedling emergence. The lowest seedling emergence percentages were obtained at the highest salinity treatment (12.2 dS m^–1). The interaction between salinity treatment and seeding depth was significant. Hypocotyl injury was implicated as a possible cause of poor seedling emergence in chickpea under saline water irrigation and was less severe when pre-germinated seeds were used. ILC 482 appeared to be more tolerant to salinity than Barka local, suggesting that breeding programmes involving regional exchange of germplasm may be helpful.     

Modelling early growth under different sowing conditions: A tool to predict variations in intercrop early stages

Early growth is a critical phase of the crop cycle, which lasts from emergence to the beginning of competition between plants and is sensitive to sowing conditions and species characteristics. Providing tools to improve the management of this critical phase in intercrops is a challenge for agroecology as these cropping systems are the subject of renewed interest for their ability to maintain yields while requiring fewer inputs. The aim of the present study was to investigate variations in early growth under different sowing conditions in different species with contrasted seed and seedling characteristics (seed mass, hypogeal or epigeal emergence, and legume and non-legume species), especially species used as intercrops. Experiments were carried out in glasshouses using different sowing depths and levels of mineral nutrition, first for each species separately, then in mixed sowings. In the first set of experiments, biomass at emergence and relative growth rate after emergence were measured and then modelled as a function of seed mass, mineral nutrition, and time to emergence. Predictive equations were tested by comparing simulations with biomass measured in the second set of experiments, for two intercrops grown under varied sowing conditions. Finally, simulations were run to analyse variations in the early growth of two intercrops (durum wheat/pea or alfalfa) under a wider range of sowing conditions (seed mass, sowing depth, and with or without mineral nutrition). Biomass at emergence was positively correlated with seed mass, and in epigeal species, was also negatively impacted by time to emergence. Relative growth rate was highly stimulated by mineral nutrition whereas its response to time to emergence varied among species. The amount of seminal reserves at emergence (in hypogeal species) and the cotyledon specific mass (in epigeal species) were correlated with the establishment of the relative growth rate. When evaluated, the model was shown to satisfactorily predict the early growth of two intercrops. Used as a simulation tool, the model indicated that all the sowing techniques tested can have a major influence on total biomass and on the proportion of each component species when competition begins. This model can thus contribute to the management of sowing techniques for sole as well as combined crops whose effects are difficult to predict and are also difficult to analyse from field experiments alone because of the number of possible combinations and interactions.     

Seedbed Characteristics and Seeding Depth Effects on Emergence and Seedling Vigour of Upland Rice

Effects of seedbed condition and seeding depth on the emergence and seedling vigour of upland rice was studied. Regardless of aggregate size distribution, seeds sown at 2 cm depth gave the maximum emergence rate (80-90 %) which was reduced to 47 % for sowing at 5 cm depth. Seeding at 10 cm depth caused total failure in emergence. When planted at 2 cm depth, aggregate size produced considerable variation in the speed of emergence but caused no significant differences in final emergence count. For seeds sown at 5 cm depth, seedbed with aggregate size < 2 mm resulted in poor emergence (12 %) while with aggregates > 8 mm reduced emergence by 34 % compared with balanced proportion of larger, moderate and smaller aggregates. Neither the seedbed condition nor seeding depth caused significant variation in seedling height or seedling dry weight.     

不同播期与基本苗对小麦生长发育及产量构成的影响

为探明稻麦周年生产条件下小麦种植适宜播期和基本苗组合,于2012—2014 年在江苏省沭阳县进行了播期和基本苗组合试验,研究了不同播期（10 月10 日、10 月17 日、10 月24 日、10 月31 日和11 月7日、11 月14 日）和基本苗（180 万/hm2、270 万/hm2、360 万/hm2、450 万/hm2、540 万/hm2）条件下小麦生长发育及产量构成。结果表明,出苗率主要受播期影响,迟播降低明显;随着播期推迟小麦叶龄逐渐变小,全生育期缩短,缩短天数少于播期推迟天数。基本苗处理对出苗率和叶龄影响不大。相同生育阶段,同一播期随着基本苗的增加茎蘖总数增多,相同基本苗处理随着播期的推迟茎蘖总数减少。播期对小麦株高、穗下节间以及穗长影响明显。单产随着播期推迟先升后降,不同播期和基本苗处理对产量构成影响显著或极显著。因此,淮北地区稻茬麦遇冷冬适宜播期在10 月17—24 日,遇暖冬适宜播期在10 月17—31日,最佳基本苗360万/hm2。     

Seed Priming with Ascorbic Acid Improves Drought Resistance of Wheat

The study, consisting of two independent experiments, was conducted to evaluate the role of seed priming with ascorbic acid (AsA) in drought resistance of wheat. In the first experiment, seeds of wheat cultivars Mairaj‐2008 and Lasani‐2008 were either soaked in aerated water (hydropriming) for 10 h or not soaked (control). In the second experiment, seeds of same wheat cultivars were soaked in aerated (2 mm ) AsA solution (osmopriming) or water (hydropriming) for 10 h. In both experiments, seeds were sown in plastic pots (10 kg) maintained at 70 % and 35 % of water‐holding capacity designated as well watered and drought stressed, respectively. Both experiments were laid out in a completely randomized design with six replications. Drought caused delayed and erratic emergence and disturbed the plant water relations, chlorophyll contents and membranes because of oxidative damage; however, root length in cultivar Lasani‐2008 was increased under drought. Hydropriming significantly improved the seedling emergence and early growth under drought and well‐watered conditions; however, improvement was substantially higher from osmopriming with AsA. Similarly, osmopriming with AsA significantly improved the leaf emergence and elongation, leaf area, specific leaf area, chlorophyll contents, root length and seedling dry weight. Owing to increase in proline accumulation, phenolics and AsA, by seed priming with AsA, plant water status was improved with simultaneous decrease in oxidative damages. These improved the leaf emergence and elongation, and shoot and root growth under drought. However, there was no difference between the cultivars in this regard. In conclusion, osmopriming with AsA improved the drought resistance of wheat owing to proline accumulation and antioxidant action of AsA and phenolics, leading to tissue water maintenance, membrane stability, and better and uniform seedling stand and growth.     

种子大小与播种方式对花生生长发育、光合特性及产量的影响

以不同粒重的花生种子为试材,采用不同播种方式,研究粒重大小和播种方式对花生生长发育、光合特性及产量的影响。结果表明,单粒精播处理可使产量增加,与传统双粒穴播相比,在一垄两行播种方式下,相对大粒种子和相对小粒种子分别增产9.77%、4.19%;一垄单行种植方式下分别增产3.44%和2.77%。无论种子粒重大小,单粒精播处理的主茎高、侧枝长和地上部干物质积累量均显著高于双粒穴播,但其荚果干重、净光合速率和单株叶面积与双粒穴播间均无显著差异。相关分析表明,叶片干重、茎柄干重与单株叶面积间呈极显著相关关系;饱果成熟期与结荚期地上部干物重之差与产量间呈显著相关关系。采用垄作双行单粒精播模式,选用饱满粒重较小的种子,可达节本降耗、明显提高经济效益的目的。