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当归采用生荒地的传统育苗方式造成生境恶化,熟地连作迎茬使当归栽培成效下降。在当归道地产区甘肃省岷县熟地栽培当归后依次轮作豌豆-黄芪,培育双豆茬口再进行当归育苗。以生荒地育苗为对照,通过测定种苗生理抗逆指标,成药期统计成活率和早期抽薹率,旨在揭示生荒地和双豆作物轮作熟地育成当归苗的抗逆性差异,为探寻适宜当归熟地育苗的轮作茬口提供科学依据和技术指标。结果表明,熟地豌豆-黄芪间茬育成当归苗根系相对电导率、氨基酸泄漏率、可溶性蛋白质和糖含量、丙二醛(MDA)含量、自动氧化速率及超氧化物岐化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性均与生荒地育成苗的差异性不显著。尽管生荒地育成苗的根系氨基酸泄漏率和自氧速率较低,CAT活性较高,早期抽薹率降低5.32%,但双豆间茬熟地育成苗根系相对电导率更低,SOD和POD活性更高,使MDA维持在较低浓度范围,越冬后根病率下降3.33%,病指下降3.06%,移栽后返青势更强,较生荒地苗返青率提高7.52%,成药率提高11.39%。因此,岷县当归道地产区熟地栽培当归后,经豌豆-黄芪双豆科轮作再行当归育苗可有效改善当归苗的生理抗逆性,减轻根际自毒作用,获得优质种苗,育苗期提倡有机栽培,加强田间管理。 相似文献
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连作重茬造成当归产量逐年下降。采用药用植物秦艽(QJ)、羌活(QH)轮作当归(DG),以当归连作为对照,通过测定土壤和药材产量指标,利用主成分分析确定各指标权重,并结合隶属综合因子分析和聚类分析,旨在揭示不同药用作物轮作当归对土壤环境与药材产量的影响,为筛选适宜当归栽培的轮作模式提供科学依据。结果表明,不同作物轮作对当归田土壤特性和药材产量均具有显著影响,秦艽轮作当归可有效改善土壤特性,使当归成药期土壤磷和钾含量处于较低水平,而有机质维持在较高水平,对土壤水分的季节调控作用更为显著,与当归连作相比较,当归成药率提高94.10%,药材单根鲜重和药材鲜产量分别提高53.46%和125.56%,而羌活轮作当归土壤pH最高,有机质含量最低,当归连作土壤有机质含量虽高,但土壤富集磷和钾,对土壤水分季节性调控作用最小,当归成药率和药材产量均低。不同轮作模式当归成药率和药材产量依次为秦艽-当归>当归-当归>羌活-当归,综合指数大小依次为秦艽-当归(0.8132)>羌活-当归(0.3315)>当归连作(0.2051)。聚类分析将3种轮作模式分为三大类,重复小区亚类间距离均小,说明不同作物轮作对土壤的调控作用不同,高寒产区秦艽轮作当归是优化调控土壤环境,提高当归产出性能的有效轮作模式。 相似文献
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甘肃岷县当归茎线虫病发生情况调查分析 总被引：1，自引：0，他引：1
2014年11月对甘肃省当归主产区岷县的5个乡镇42块当归田采用随机取样方法进行了系统调查,以了解当归茎线虫病的发生分布情况。调查结果表明,当归茎线虫病田间病株率达到25%~79%,病情指数达15.8~68.0,其中,以梅川镇梅川村发病最严重,发病率达79%,病情指数达68.0;在不同土壤深度、不同土壤类型、不同茬口作物根际土壤中均有腐烂茎线虫分布,但群体密度不同。以5.0~10cm土层分布比例较大,每100g达230头;以黑土中病原线虫密度较大,每100g达1 102头,与黄土和沙壤土相比线虫密度差异显著(P0.05);不同茬口作物中以黄芪茬口病原线虫密度较大,每100g达590头,与马铃薯、大豆、小麦茬口相比线虫密度差异均显著(P0.05)。 相似文献
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高寒区农茬口对当归田杂草群落特征的影响 总被引：2，自引：0，他引：2
农田杂草危害是高寒区当归生产的主要限制因子。采用田间调查和统计鉴定相结合的方法,研究了甘南藏族自治州卓尼县培育的马铃薯和油菜茬口当归栽培田杂草群落动态,以当归重茬为对照,旨在揭示茬口特性对当归田杂草消长动态的影响,为筛选适宜栽培当归的农茬口和田间杂草防控提供科学依据。结果表明,在试验茬口当归田共发生杂草15种,隶属9科15属,主要优势种群为锦葵、欧洲千里光、苦苣、繁缕、刺儿菜和甘露子。当归田杂草种类、密度、多样性和生物量因茬口和季节的不同而异,季相消长跃变程度更大,随季节延后杂草多样性下降,优势种杂草利用资源的相似性更高,锦葵和欧洲千里光随当归返青而滋生,随当归生长发育而迅速蔓延,成为占优势的恶性杂草,对当归的危害性最大,导致杂草群落稳定性降低,在当归重茬和马铃薯茬田单生优势度更为突出,优势杂草潜在恶化危害性增大,但在油菜茬田杂草生长量最小,与当归生长竞争势较弱,使当归始终占据优势生态位,说明油菜茬口较利于当归栽培,但根据恶性杂草物候特征及早防除更为关键。 相似文献
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以新疆石河子市第八师147团紫花苜蓿为研究材料,探究不同刈割茬次及生育期苜蓿青贮营养品质和发酵品质间的差异。选择3个刈割茬次,现蕾期、初花期和盛花期3个生育期处理;分别于青贮发酵第3、9、15、30、45、60天取样测定其青贮品质。结果表明:苜蓿青贮过程中,刈割茬次与生育期的交互作用对干物质、中性洗涤纤维、粗蛋白、乳酸和乙酸含量产生极显著影响(P<0.01),苜蓿青贮在发酵过程中会降低营养物质的含量,发酵60 d时,第3茬盛花期苜蓿青贮的DM含量最高,达到39.03%,第3茬现蕾期苜蓿青贮的酸性洗涤纤维和中性洗涤纤维含量最低,第1茬现蕾期CP、WSC含量最高,分别是20.21%和4.39%,第2茬现蕾期的乳酸和乙酸含量相对其他处理较高,第1茬现蕾期氨态氮含量最低。各处理综合评价排序:第1茬现蕾期处理>第3茬现蕾期处理>第1茬初花期处理>第2茬现蕾期处理>第3茬初花期处理>第1茬盛花期处理>第3茬盛花期处理>第2茬初花期处理>第2茬盛花期处理。刈割越早,苜蓿越幼嫩,营养品质高,适口性好,并有利于植株再生,苜蓿青贮的营养品质和发酵品质也较晚刈割的其他处理好。因此,控制苜蓿刈割时间可改善苜蓿青贮营养、发酵品质,提高苜蓿利用率。 相似文献
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针对亚热带地区伏旱频发条件下,丝茅入侵细叶结缕草草坪引起功能退化的问题,通过设置4个干旱梯度(水分充足、轻度、中度和重度干旱),采用取代试验设计了5个不同比例的丝茅入侵细叶结缕草草坪试验,进行60 d干旱处理后,测定丝茅和结缕草地下和地上相对产量、相对产量总和、攻击力、竞争平衡指数等竞争指标,分析两种植物的株高、分蘖数、叶片数、生物量和根冠比等生长指标,比较超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、可溶性糖(SS)、可溶性蛋白(SP)、脯氨酸(Pro)、丙二醛(MDA)等生理指标,研究干旱对两种植物之间的竞争、生长及抗性系统的影响。结果表明:1)干旱程度和丝茅入侵比例对两种植物的地上和地下竞争指标产生显著影响(P<0.05),轻度干旱且丝茅入侵比例≤30%时,结缕草地下攻击力指数和地下竞争平衡指数为正值,中度和重度干旱使结缕草种间竞争力丧失,当丝茅入侵比例≥20%时,拮抗作用使结缕草易被排挤出群落。2)干旱主要影响结缕草地下竞争力,丝茅入侵主要影响结缕草地上竞争力,干旱和丝茅入侵协同作用对结缕草地下攻击力和地下平衡指数影响大于地上部分,随干旱程度和丝茅入侵比例增加结缕草地上和地下竞争力降为负值。3)轻度干旱利于两种植物生长,中度和重度干旱降低了结缕草的株高、分蘖数、叶片数和单株生物量,对丝茅影响较少;>10%丝茅入侵比例限制了结缕草分蘖数和叶片数,>20%则降低了结缕草单株生物量和根冠比,干旱和丝茅入侵协同作用抑制了结缕草生长与再生能力。4)结缕草SOD、POD和CAT含量随干旱程度增加而显著增加(P<0.05),轻度干旱对丝茅SOD无影响而降低了CAT活性(P<0.05);>10%丝茅入侵比例增加了结缕草SOD活性,>20%增加了CAT活性,>30%增加了POD活性(P<0.05)。干旱对结缕草影响为CAT>SOD>POD,对丝茅为SOD>POD>CAT,丝茅入侵比例对两种植物影响均为SOD>CAT>POD,干旱对结缕草抗氧化酶系统影响大于丝茅入侵。5)轻度干旱增加了结缕草SS和SP的含量(P<0.05),增加了丝茅SP的含量,中、重度干旱使两种植物的SS、SP、Pro和MDA含量增加(P<0.05);>10%丝茅入侵比例增加了结缕草SS、SP和MDA的含量(P<0.05),>20%时增加了Pro的含量(P<0.05),干旱程度和丝茅入侵比例协同作用加剧了两种植物的受伤程度,对生境胁迫时结缕草反映为SS>Pro>SP>MDA,丝茅反映为MDA>Pro>SS>SP。故夏季避免重度干旱和控制丝茅侵入比例≤10%是维持结缕草草坪健康的基本养护要求。 相似文献
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不同早熟禾品种对干旱胁迫的生理响应及抗旱性评价 总被引：5，自引：0，他引：5
为鉴定评价早熟禾幼苗抗旱性,将14个早熟禾品种的种子经消毒后播种在塑料花盆中,出苗后间苗,2~3个真叶定株,每盆留生长一致、分布均匀的幼苗15株,定期浇水,以保证幼苗的正常生长。待生长到3~4个真叶时进行干旱处理,依据Michel公式计算不同水势所需的PEG-6000的量,然后加入PEG-6000溶液进行干旱处理,处理的水势梯度为0 MPa(即为对照),-0.3,-0.6,-0.9和-1.2 MPa。处理后每2 d进行称重补水以维持溶液浓度。设干旱处理与对照(正常浇水)两组,对14个早熟禾品种幼苗进行模拟干旱胁迫,4次重复。测定叶绿素(CHL)含量、丙二醛(MDA)含量、脯氨酸(Pro)含量、过氧化物酶(POD)以及超氧化物歧化酶(SOD)活性等生理生化指标。结果表明,随着干旱胁迫的加剧,早熟禾幼苗叶片CHL含量呈下降趋势;Pro含量、MDA含量、SOD活性总体呈上升趋势;POD活性总体呈先降再升后降的趋势;利用隶属函数分析得出14个早熟禾品种的抗旱性强弱顺序依次为:3号恩托佩草地早熟禾>10号细叶早熟禾>1号优异草地早熟禾>2号斗士草地早熟禾=9号蓝钻草地早熟禾>7号草地早熟禾>11号草地早熟禾>4号草地早熟禾>5号瓦巴斯草地早熟禾>8号早熟禾=13号肯塔基草地早熟禾>14号草地早熟禾>6号莫诺波利草地早熟禾=12号菲尔津草地早熟禾。 相似文献
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不同播种量对甘肃礼县掌叶大黄育苗质量的影响 总被引：2，自引：0，他引：2
通过在甘肃礼县采收三年生掌叶大黄种株种子并采用不同播种量(35,45,55,65,75和85 kg/hm2)育苗,育苗结束后测定苗栽质量指标,移栽定植到大田后定期测定成活率,旨在揭示播种量对掌叶大黄苗栽质量的影响,为其规范化栽培提供依据。结果表明,在甘肃礼县育苗时种子播种量对掌叶大黄育苗质量具有极显著影响,在35 kg/hm2最低播种量基础上,随着播种量的增大育成苗栽数持续增多,苗栽产量先显著提高后下降,但苗栽根长、根粗、单苗重和根系TTC还原强度等个体质量指标均呈降低趋势,播种量为65 kg/hm2时苗栽产量最高,单苗鲜重和根系TTC还原强度减小程度较轻,苗栽综合指标优异,生长健壮,大小适中,产苗数多,移栽成活率高,说明从育苗质量和育苗效益综合考虑,甘肃礼县掌叶大黄育苗适宜种子播种量为65 kg/hm2。 相似文献
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This research aimed to identify a suitable planting pattern for oilseed flax production in a dry-farming region. A long-term field experiment was started in 2012 with a 4-year crop rotation cycle,designed to measure the effects on flax crop performance of previous crop,and various patterns of flax planting interval within the four-year rotation,compared with continuous flax cropping. Crop parameters measured included plant height,stem diameter,dry matter accumulation and distribution,and the experiment included six different crop rotation patterns：Flax→flax →flax→flax［（F）FFF］;Flax→wheat→potato→flax［（F）WPF］;Flax→potato→flax→wheat［（F）PFW］;Flax→ flax→wheat→potato［（F）FWP］;Flax→wheat→flax→potato［（F）WFP］and flax→wheat→potato→wheat［（F）WPW］. Results for the ninth year showed significantly increased grain yield（29. 89%-109. 57%）in crop rotation treatments compared with continuous cropping of oilseed flax. The ranking of the six tested rotations for yield was：（F）WPW>（F）FWP>（F）WFP>（F）PFW>（F）WPF>（F）FFF. The grain yield of oilseed flax was significantly affected by previous crop,frequency and years interval of flax cropping and number of years of continuous flax cropping. Yield was increased by 54. 45%-59. 29% under wheat stubble and potato stubble compared with oilseed flax stubble,and increased by 30. 66% and 109. 57%,respectively,under 50% and 25% frequencies,compared with 100% frequency. The grain yield of oilseed flax under two-year continuous cropping was higher by 29. 89% than four-year continuous cropping,and increased with increase in years interval between flax crops. Correlation analysis identified a significantly positive correlation between oilseed flax grain yield and effective capsule number,branch number and 1000-seed weight. The effective capsule number,branch number and 1000-seed weight of oilseed flax under rotation treatment were increased by 35. 88%-108. 91%,15. 47%-46. 19% and 14. 61%-16. 34%,respectively（P<0. 05）,compared with continuous cropping. In addition,the high grain yield of oilseed flax was accompanied by an increase in plant height,stem diameter and dry matter accumulation and these increases were,respectively,5. 11%-42. 24%,2. 77%-39. 92% and 31. 25%-117. 89% under the rotation regimes,compared with continuous cropping. Reduction in the number of years of continuous cropping years,change of crop stubble,decreased flax planting frequency and increased of interval between flax crops also improved flax crop performance. In summary,crop rotation improved the vigor of oilseed flax,resulting in greater plant height and stem diameter,improved dry matter accumulation and distribution,leading to increased branch number,effective capsule number and 1000-seed weight,and increase in the crop yield of oilseed flax. The results indicated that a multiple-crop rotation pattern was an effective way to avoid the yield reduction caused by continuous cropping in oilseed flax. The rotation： Flax→wheat→potato→wheat performed best among those tested and can be recommended as an appropriate cropping rotation for oilseed flax production in the dry region of northwest China. © 2022 Editorial Office of Acta Prataculturae Sinica. All rights reserved. 相似文献
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The study used nursery and field experiments to investigate why recruitment of Dobera glabra (Forssk) Poir., a native food source for both humans and livestock, often fails in the semiarid rangelands of Afar, Ethiopia. We hypothesized that soil water limitations and browsing by livestock would be the primary mechanisms accounting for the failure of natural regeneration. We used three sets of experiments—1) seedling performance in response to shade and watering in a nursery, 2) field regeneration with and without browsing, and 3) regeneration beneath trees with and without browsing—to examine regeneration success. Seedlings were established in plots from seeds sown directly into the soil for nursery and field experiments, but natural germination occurred beneath trees. Survival and relative growth rates (RGR) were used to monitor seedling performance. Seedlings that received neither shade nor watering treatments had lower seedling survival (53 ± 15%) as compared with other treatment combinations. Highest seedling survival was recorded under shade and 1 d watering s wk-1 treatment combinations (92 ± 1%). However, shade treatments had a minimal increase on seedling RGR. Water limitation is not a crucial limiting factor for D. glabra recruitment, as 53% of the seedlings survived without both shade and supplemental water for 1 yr. Field experiments, however, demonstrated that browsing greatly reduced seedling survival (below 15%) and suppressed growth of surviving seedlings, suggesting that browsing is the major factor preventing natural recruitment. Natural recruitment of D. glabra is unlikely with the existing continuous and intensive grazing/browsing in Afar rangelands, where the mobility of pastoralists is restricted. We suggest that planting nursery-raised seedlings in home gardens of settled pastoralists and establishment of grazing reserves in some key range sites that contain D. glabra could help offset the recruitment failure of native food species D. glabra in Afar rangelands. 相似文献
13.
小麦/玉米/大豆套作的产量、氮营养表现及其种间竞争力的评定 总被引：21，自引：0，他引：21
采用多年大田试验研究了小麦-大豆(A1)、小麦-甘薯(A2)、玉米(A3)、小麦/玉米/大豆(A4,麦/玉/豆)和小麦/玉米/甘薯(A5,麦/玉/薯)5种种植模式的生物积累和氮素吸收特性,以探讨麦/玉/豆套作体系的种间竞争力变化规律。试验通过土地当量比(LER)、种间相对竞争力(A)、氮营养竞争比率(NCR)等指标来评定不同套作系统内的作物竞争力。结果表明,麦/玉/豆套作表现出明显的套作优势(LER＞1、Awc<0、Acs>0、NCRwc<0、NCRcs>1),玉米始终占据套作系统的优势生态位,小麦、大豆处于竞争劣势;与A1、A2、A3及A5相比,麦/玉/豆套作提高了各作物在开花期(或吐丝期)与成熟期的籽粒产量与吸氮量和地上部植株的总生物量与总吸氮量;各作物的生物量与吸氮量在处理间的变化规律为套作＞单作、大豆茬口＞甘薯茬口,以A4处理最高。麦/玉/豆套作的全年总经济产出比麦/玉/薯套作平均高28.02%。 相似文献
14.
Sourour Abidi Salah Benyoussef Hichem Ben Salem 《Journal of animal physiology and animal nutrition》2021,105(1):51-58
This study aimed to investigate the replacement value of half time grazing of wheat stubbles by vetch, which had been cropped under the context of conservation agriculture (CA). Three grazing treatments were evaluated on Barbarine lambs (initial BW 18 ± 1.42 kg). Treatment 1 consists of 6-hr grazing on dried vetch only (V). For treatment 2, the sheep were grazing 3 hr on wheat stubbles in morning and 3 hr on dried vetch in the afternoon (VWS). Treatment 3 consists of 6-hr grazing of wheat stubbles only (WS). At grain maturity stage, biomass yield of vetch averaged 7 tons DM/ha allowing a grazing period of 2 consecutive months. Along this period, vetch conserved its pods indehiscent. Biomass and nutritive value of vetch and wheat stubbles were decreasing from the start to the end of the grazing period. Residual biomass was higher in vetch and wheat stubble assigned to treatment VWS. WS lambs spent more time on walking and standing, while V and VWS lambs allocated more time on biomass uptake. The DM, OM and CP intakes were higher in animal grazing vetch alone or combined to wheat stubble. Rumen fermentation parameters (pH, ammonia nitrogen concentration and protozoa count) were not affected (p > .05) by any of the three treatments. The average daily gain of lambs on V and VWS lambs was three times greater (p < .05) than that of WS lambs (164, 152 and 49.5 g respectively). Cold carcass yield averaged 444, 428 and 388 g/ kg for lambs assigned to V, VWS and WS treatments respectively. It is concluded that grazing vetch alone or combined with WS increased substantially the growth performance and carcass yield of lambs compared with WS grazing only. Therefore, dried vetch grazing could be a solution to make possible mulching and biomass uptake by sheep under the context of CA. 相似文献