稻田油菜免耕直播密度与播种期探讨

为完善稻田油菜免耕直播技术，探讨其在本地的最适播种期和最佳密度，2002～2003年度在安乡进行了播期和密度试验。通过分析播期、密度与产量及其构成因素的关系，认为稻田油菜免耕直播在9月底到10月份均可播种，都能获得一定的产量，且播期越早，产量越高；播种密度以每公顷36万～45万株时为最佳。     

H2O2浸种对晚直播油菜生长及产量的影响

H2O2浸种能够促进低温胁迫下油菜种子的物质代谢,为适应直播油菜不同播期生产需求,研究H2O2浸种对不同播期油菜生长发育的影响,提高晚直播油菜产量。2017年以南农油4号为材料,设置播期(早播10月5日,晚播10月25日)和0.05%的H2O2浸种两个因素,采用露天盆栽试验观察油菜在越冬期的光合特性及全生育期生长发育动态。结果表明:(1)晚播使油菜苗期延长而蕾薹期缩短,初花前可利用积温从1349.5℃·d减少至1095.5℃·d,导致油菜营养生长期干物质积累减少,而生殖生长期活动积温升高,相比早播的1042.5℃·d升高为1119.5℃·d。由于晚播生育期缩短,活动积温减少,干物质积累降低,最终显著减产8.3%。(2) H2O2浸种处理对早播油菜萌发出苗及地上部生物量无显著影响,但显著抑制了地下部生物量及光合能力,降低了越冬期干物质积累,继而影响后期产量形成,最终造成油菜显著减产,降幅为10.9%。(3) H2O2浸种处理促进了晚播油菜萌发出苗,增大叶面积,促进了油菜干物质积累使产量显著升高,增幅为15.7%。因此在油菜晚直播条件下,可通过H2O2浸种处理以提高产量。     

不同播期对鲁西南蒜后直播短季棉生长发育及产量的影响

为了探讨鲁西南棉区蒜后短季棉直播的可行性及不同播期对直播短季棉生长发育及产量的影响。以短季棉新品种鲁棉532和鲁棉551为材料，研究不同播期对棉花生育期、农艺性状及产量的影响。结果表明：随着播期的推迟，出苗时间缩短，开花期到吐絮期生育时间变长，株高增加，第一果枝节位、单株结铃数和铃重降低；随着播期推迟，籽棉产量和皮棉产量均降低，霜前花率降低，衣分降低显著。     

播种期和密度对短季棉品种冈早1号产量的影响

采用二因素(播期和密度)4水平随机区组设计,于湖北黄冈地区研究了不同播期和密度对短季棉品种冈早1号产量的影响。结果表明:随着播期的延迟,产量呈下降趋势,且在6月13日往后,随着播期的推迟,冈早1号的产量下降明显;随密度的增加产量呈现先增加后减少的趋势,但4个密度处理之间的产量差异均未达显著水平,在本试验设计的密度范围内,冈早1号具有较强的密度弹性。     

机直播油菜播期与密度试验初报

以荣华油6号双低油菜品种为材料,采用4个播期、3种密度两因素随机区组试验设计,研究播期和密度对机直播油菜产量的效应。结果表明:当播期为9月30日,密度为22.5万~30万株/hm2时,机直播油菜产量最高;密度过大,播期过早、过迟均会导致减产,但随着播期的推迟,适当提高密度可增加产量。     

播期和密度对冬小麦籽粒产量和营养品质及生理指标的影响

为了研究播期和密度对冬小麦籽粒产量和营养品质及生理指标的影响,以中筋小麦中任1号为材料,在大田条件下进行不同播期和密度试验.结果表明,旗叶展开后0～28 d,早播和适播的小麦叶绿素含量高于晚播,生育后期晚播比早播和适播叶绿素含量高,叶绿素含量在不同密度处理间差异不显著.晚播比早播和适播旗叶平均含氮量分别高7%和4%,旗叶含氮量在不同密度处理间差异不显著.播期对籽粒产量及其构成因素有显著影响,籽粒产量和蛋白质产量以适播处理最高,在不同密度处理间除穗粒数差异显著外,其余均不显著.播期对清蛋白、醇溶蛋白和总蛋白含量有显著影响,对球蛋白和谷蛋白含量影响不显著,总蛋白含量以A2播期处理最高.除球蛋白外,总蛋白及其他组分舍量在密度处理问差异均不显著,以B1处理最高.研究结果说明,籽粒产量和蛋白质产量以A2B2处理最高,营养品质以A281处理最佳.旗叶展开后21 d时,旗叶叶绿素含量与清蛋白和球蛋白含量呈极显著或显著正相关(r=0.73**,r=0.57*).     

利用栽培措施控制油菜菌核病的研究

以2个甘蓝型油菜品种为材料，利用自然鉴定和人工接种方法研究不同播期和不同密度等栽培措施对控制油菜菌核病的作用。结果表明，品种 播期对油菜菌核病的影响均达显著水平，种植密度对油菜菌核病的影响不显著，选用抗（耐）病性品种和适当晚播可有效控制或避开油菜菌核病发生。合理密植可提高油菜产量。     

不同栽培措施对直播早熟油菜机械收获相关性状的影响

油菜机械化生产是目前油菜高效栽培的主要途径之一,为探究适合直播早熟油菜机械收获的最佳栽培模式,以特早熟甘蓝型油菜品系‘1358’为材料,共设置3个播种期、3个栽培密度和2个施肥水平,研究不同栽培措施对直播早熟油菜机械收获相关性状的影响。结果表明:迟播能缩短油菜的生育期,而密度和肥料处理对生育期影响不大。不同处理间,株高随着播期推迟和密度增大而降低,增施肥料能增加油菜株高。一次分枝的数量和分枝位与播期、密度显著相关,而肥料对其影响不显著。在油菜分枝位方面,3个因素的组合处理均在68 cm以上,适合油菜机械收获的要求。此外,早熟油菜播种越早产量越高,增加施肥量能提高油菜产量。本研究中,在同一施肥量条件下,10月20日播种,随着密度增加减产幅度增大;10月30日和11月9日播种,产量则随着密度的增加而提高。综合农艺性状和产量表现,提出了直播早熟油菜10月底播种,每公顷栽培90万株,施用复合肥(有效成分48%,N、P、K含量均为16%)900 kg的农机与农艺相配套的最优栽培模式。     

播期、种植密度及施氮水平对稻茬免耕直播油菜产量的影响

以中油杂8号为材料,在稻茬免耕直播的条件下,研究了不同播期、不同密度以及不同施氮水平对油菜产量的影响.结果表明：稻茬免耕直播油菜在大通湖区的适宜播种期为10月10～15日,密度为每公顷30万～45万株,施氮水平为纯氮180kg/hm^2.     

水稻套种直播油菜技术研究

以湖南农业大学油料作物研究所提供的湘杂优753为供试品种，分3个播期（晚稻收割前7 d、晚稻收割前3d和晚稻收割后板田撒播）和2种种子处理方式（用烯效唑处理和不用烯效唑处理）对稻田套播油菜的产量及其产量结构进行了研究。结果表明：播种时间和种子处理方式对套播油菜产量均有显著影响，水稻套种油菜以烯效唑浸种后晚稻收割前3d直播最好。     

棉花营养钵育苗提高出苗率的关键技术

近年来,杂交棉种在长江流域大面积推广,确实为棉花单产提升了一个台阶.但由于杂交棉种制种工序复杂,投入大,因而种价较高,因此,棉农购种用量很少;播种时,基本上是一钵一籽,稍有不慎,就会出现缺苗断垄现象.究其原因,既有种子质量问题,也存在受天气不适、育苗操作技术不当等因素影响所致.如何采取有效措施,确保一播全苗,笔者介绍以下技术,供广大棉农参考.     

洞庭湖区双季稻直播适宜用种量研究

针对直播稻用种量越来越大的情况,于2009年在沅江草尾镇进行了早晚稻直播不同类型品种用种量研究,初步摸索出了洞庭湖区双季稻直播适宜的用种量,其中早稻直播中熟常规品种适宜用种量为120～150 kg/hm2,中熟早杂品种适宜用种量为37.5～45 kg/hm2;晚稻直播常规中熟早稻品种适宜用种量为105～127.5 kg/hm2,晚稻直播中熟早杂品种适宜用种量为45～52.5 kg/hm2。     

种衣剂包衣 防治棉苗病虫技术研究

试验结果表明，棉籽包衣是一项省工节本，防病治虫保苗效果好的新技术。针对我省沿江棉区生态条件和苗期病虫发生的特点，筛选适用的剂型。在本试验中以福美双７％，多菌灵５％、呋喃丹８％三者组配复制最为理想。     

油茬田免耕直播稻适宜播期和播量的研究

2002～2003年在湖南省石门县开展了油茬田免耕直播稻的适宜播期和播种量的研究,探讨了3个播种期和3个播种量对两优培九的生育期、株高、总叶片数、出叶速度、茎蘖动态、产量和产量构成因素的影响.试验结果表明,两优培九作一季中稻免耕直播栽培,以5月中旬播种,播种量22.5 kg/hm2较适宜.     

Establishing new guayule lines by direct seeding

Direct seeding of guayule (Parthenium argentatum Gray) in west Texas has been successful. However, studies have involved only USDA and `Mexican Bulk' lines. New selections developed by plant breeders must be screened for their adaptability to direct seeding. The objective of this study was to evaluate the standard establishment and production parameters (biomass, rubber and resin content, rubber and resin yield) of six direct seeded guayule selections (AZ-R1, AZ-R2, CAL-6, CAL-7, UC-101, and UC-104). An experiment was initiated on a Delnorte gravelly loam on 23 July 1993 at the Texas Agricultural Experiment Station near Fort Stockton, TX. Conditioned and raw seed of the six guayule selections were planted 10 mm deep on raised beds spaced 1 m apart. Laboratory seed germination ranged from 34–92%. Seedling density was greatest with conditioned seed (61 seedlings/m) versus raw seed (37 seedlings/m) when averaged across all lines 30 days after planting. Individually, seedling density in plots established by conditioned seed was greatest with CAL-6 (68 seedlings/m), UC-104 (66 seedlings/m), AZ-R1 (65 seedlings/m), UC-101 (64 seedlings/m), and CAL-7 (61 seedlings/m), and were significantly greater than the seedling density in plots established with raw seed. Both conditioned and raw seed produced adequate guayule stands. Nonetheless, conditioning improved germination, and in the field, conditioned seed was observed to germinate and emerge quicker resulting in more efficient irrigation management. The AZ-R1 seedlings were the most vigorous and were tolerant to flea beetles (Epitrix sp.). Plants were thinned to a 0.36 m spacing in April 1994. Six plants from each selection in the conditioned seed treatments were harvested on 23 February 1995 and 6 March 1996. Each plant was divided into branch (clipped 10 cm above the soil surface) and root sections. Biomass and rubber and resin yields were greatest in the branch versus root fractions. Total rubber yield (branches plus roots) at both harvests was greatest in selections AZ-R2 and UC-104.     

小粒大豆播种深度初探

选用“通农 14”百粒重 10g的小粒大豆种子 ,按 1～ 6cm不同深度播种 ,结果表明小粒大豆播种深度以 2～ 3cm深度处理为最佳播种深度。方差分析结果表明 ,不同播种深度处理间差异达到极显著水平 (F65 2 5 ※※ >F0 0 1=5 65 )。     

Impact of seeding rate on annual ryegrass performance

Annual ryegrass (Lolium multiflorum Lam.) is a primary forage resource for livestock producers throughout the south‐eastern USA during the winter‐growing season. It is important for livestock producers to begin grazing annual ryegrass as early as possible and any management practices maximizing early season production could be beneficial. To assess the impact of seeding rate on subsequent yield, yield distribution, quality, seedling density, and end‐of‐season plant and tiller density, a 2‐year study was initiated at four locations in Louisiana. Three annual ryegrass cultivars, varying in seed size, were established at four seeding rates based on pure live seed (PLS) rates of 400, 800, 1200 and 1600 PLS m^?2. There was no advantage in total yield from increasing seeding rates beyond 800 PLS m^?2. However, first‐harvest yields increased from 360 to 930 kg dry matter (DM) ha^?1 as seeding rate increased from 400 to 1600 PLS m^?2. Crude protein and neutral‐detergent fibre concentrations, and in vitro DM digestibility, were not affected by seeding rate. Seedling density and end‐of‐season plant numbers increased as seeding rate increased. However, stems per plant decreased as seeding rate increased, indicating compensatory tillering for the reduced plant numbers observed at the lower seeding rates. These results indicate first‐harvest yield can be increased by planting at higher seeding rates but total yields are not increased.     

水稻喷直播栽培技术

喷直播就是把东方红１８型喷雾机的喷水装置改为喷粉装置 ,将芽谷通过喷粉管喷播到田里的一种新的机械直播技术。该技术是浙江临海农民首先试验的 ,经农技部门总结和试验示范 ,开始在台州市内应用。该技术具有省工省力增收的优点 ,受到种粮大户和农民的欢迎。１９９７年开始试验 ,２０００年种植面积已有６７０多ｈｍ２。目前 ,该项技术主要在早稻上应用 ,２０００年作者利用嘉早９３５品种进行了翻秋喷直播对比试验。现把该项技术主要结果介绍如下 :一、喷直播技术的优点１．省工省力节本喷直播栽培同一般的手直播稻一样 ,减少了传统育秧移…     

A precision seeding device for true potato seed

A prototype apparatus was developed which can select and deliver single true potato seed to a specific location. The principle features of the unit include a system of vacuum and pressure nozzles connected to a rotating head to select and hold the individual seeds then eject them for planting. An airbrush was incorporated in the design to remove multiple seed from the nozzles. A small orifice and the radially oriented airbrush were fixed as a result of preliminary tests. Results of performance studies of the unit indicated that 84% single seed selection was possible. Parameters which influenced the performance of the unit were airflow rate from the airbrush and the level of vacuum in the manifold.     

Sward maintenance of Lolium multiflorum by slurry seeding

A field investigation into the effect of slurry seeding on the dry-matter yield and persistence of an Italian ryegrass sward was assessed over a 3-year period (1984–86) under a regime of three cuts per season combined with sheep grazing in early spring and late autumn. Results showed that slurry plus seed treatments produced up to 30% more herbage dry matter and a significantly higher tiller density than where no slurry or seed were used. Slurry application with and without seed also reduced the proportion of weed grasses ( mainly Poa spp.) in the sward. It is concluded that slurry seeding is a useful technique for extending the productive life of an Italian ryegrass sward.