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养花者常把非洲凤仙当作一年生花卉栽培。每年都要播种育苗,不但增加了开支,且育苗管理十分精细,苗期生长缓慢,育苗时间长。况且,一年生苗的花期比周年栽培的短一半。因此我们在生产实践中,初步摸索出周年栽培技术,获得了不匪的经济效益。周年栽培的核心是保温越冬及扦 相似文献
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随着茄子栽培面积的扩大和连年种植,各种土传病害发生相当普遍,危害程度也越来越重,如茄子黄萎病、枯萎病、青枯病等已成为制约茄子生产的顽症,常规农药防治效果不好,嫁接已成为克服土传病害、提高茄子产量和效益的必须手段. 相似文献
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由于一品红株型优美、颜色鲜艳、摆放时间长,因而越来越受到广大消费者的喜爱。随着销售量的逐年攀升和种植水平的不断提高,一品红供应市场的时间已不仅仅局限于从圣诞节到春节,目前已经实现全年生产,周年供应市场。笔者经过几年的生产实践,总结出长江中下游地区一品红周年生产的栽培技术。 相似文献
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Annual Brussels sprouts 总被引：2，自引：0，他引：2
Annual flowering in Brussels sprouts, originally found in one plant in 1953, is dominant over biennial flowering and the difference is monogenic. Deviations from expectations may be the effect of potentially annual plants which do not come to flower owing to a very late time of flowering.
Samenvatting In 1953 werd één spruitkoolplant gevonden, die in het jaar van uitzaaien bloeide. Op grond van de resultaten met F1's en F2's van kruisingen tussen éénjarig en tweejarig en terugkruisingen wordt geconcludeerd tot dominantie van éénjarigheid en tot een monogeen verschil. Afwijkingen van verwachtingen betreffen steeds een tekort aan éénjarigen en worden toegeschreven aan het niet tot bloei komen van potentiële éénjarigen door een zeer late bloeitijd, welke genetisch geïnduceerd wordt door de tweejarige ouder, die niet op vroege bloei in het eerste jaar kan worden geselecteerd.相似文献
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R L. De Haan C. C. Sheaffer D. A. Samac J. M. Moynihan D. K. Barnes 《Journal of Agronomy and Crop Science》2002,188(6):417-425
Annual Medicago species (medics) have characteristics that may make them a valuable addition to agricultural systems in the Upper Midwest, USA, but few genotypes have been evaluated. The objective of this research was to identify medic germplasm exhibiting traits that are desirable for cultivars intended for multiple uses in the region. Australian annual medic cultivars and plant introductions (PI) representing seven species were evaluated for Phytophthora root rot (Phytophthora medicaginis Hansen et Maxwell) resistance, shade tolerance, growth habit, dry matter accumulation, maturity after 9–10 weeks of growth, and potato leafhopper (Empoasca fabae Harris) yellowing. Medicago polymorpha L. plant introductions PI 197346, PI 459135, and PI 283653 were resistant to Phytophthora root rot. Kelson [Medicago scutellata (L.) Mill.] and PI 419241 [Medicago tornata (L.) Mill.] were tolerant of shade, while M. polymorpha entries Santiago and SA 9032 were intolerant. In growth habit comparisons, PI 419241 and PI 368939 (M. polymorpha) grew less than 11 cm tall, while Kelson and SA 5762 (M. polymorpha) grew at least 27 cm tall. Dry matter production 10–12 weeks after emergence was greatest for PI 197339 (M. polymorpha) and Kelson. At that time, the earliest maturing entries, PI 226517 (M. polymorpha) and Sava (M. scutellata), had begun to senesce, while the latest maturing entry (PI 419241) was still vegetative. Paraponto (Medicago rugosa Desr.) was highly resistant to potato leafhopper yellowing. None of the medic entries evaluated combined all of the desirable traits for Upper Midwest cultivars, but the traits were all present within available germplasms. Plant breeders could develop adapted cultivars by combining favourable traits from several medic genotypes. 相似文献
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Sampling and monitoring of surface runoff in Bengbu urban area were carried out during rainy seasons in 2009, and 40 rainfall samples from 7 sampling sites were analyzed. Discharge processes of runoff pollutants during rain events and relationships of the processes with rainfall characters were discussed. Then some aspects were analyzed, such as city surface pollutants, land style and system of drains, etc. Finally annual total quantity of runoff pollution from Bengbu urban area was calculated based the method. 相似文献
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为探索土壤微生态对稻-油系统周年耕作方式的响应机制,利用湘北洞庭湖区长期免耕直播土壤,设置稻-油轮作试验,通过比较双免耕双直播和旋耕抛栽土壤中酶活性、微生物数量、群落多样性和菌群功能等指标的差异,研究不同耕作方式对土壤微生态的影响。宏基因组测序表明,细菌群落在2种耕作方式下组成相似,双免耕双直播下细菌多样性更高;真菌群落在不同耕作方式下有不同的真菌类型,但旋耕抛栽下真菌多样性更高。菌群功能分析显示,需氧和兼性厌氧原核微生物相对丰度在双免耕双直播中较高;与氮代谢相关的原核微生物相对丰度在双免耕双直播中较高,而与碳代谢相关的原核微生物的相对丰度在旋耕抛栽中较高。可培养微生物数量测定表明,免耕土壤中可培养细菌、真菌、放线菌和硝化细菌的数量都较旋耕极显著降低,而氨化细菌数量极显著增加。酶活性分析表明,双免耕双直播土壤中的脲酶活性比旋耕抛栽提高了58.12%,而转化酶、磷酸酶和纤维素酶的活性分别降低了28.57%、11.00%和57.73%。本研究表明稻-油轮作双免耕双直播的耕作方式有利于提高土壤中细菌的多样性、需氧和兼性厌氧原核微生物的相对丰度,有利于土壤中氮的转化和利用,为洞庭湖区稻-油系统合理耕作方式的选择提供依据。 相似文献
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小麦—玉米周年生物节水栽培品种的筛选 总被引：1，自引：1，他引：0
为了在小麦—玉米周年栽培中提高作物产量与水分利用效率,于2008—2009年栽培季在大田栽培条件下,以当前胶东地区推广种植的13个小麦品种与14个玉米品种为供试作物进行小麦—玉米周年生物节水栽培品种筛选试验,以小麦全生育期不灌溉、拔节期灌溉1次与拔节、灌浆期灌溉2次3个水分供应水平、玉米全生育期不灌溉与开花期灌溉1次2个水分供应水平处理,结果表明:试验条件下,供试小麦品种的产量在5992.485kg/hm2～10045.500kg/hm2之间,水分利用效率(WUE)在14.314kg/(hm2·mm)～24.238kg/(hm2·mm)之间,玉米品种产量在7118.535kg/hm2～12220.700kg/hm2之间,WUE在13.467～26.124kg/(hm2·mm)之间,根据产量、耗水量、WUE、灌溉水生产效率等指标进行聚类分析,将供试小麦品种分为5类,玉米品种分为4类。在小麦生育期内降水250mm、玉米生育期内降水460mm左右时,济麦21、青丰2号、济麦22、DH155等4个小麦品种与先玉335、鲁单981、登海3622、蠡玉16、丹玉86等5个玉米品种具有高产高WUE的特点,可作为小麦—玉米周年生物节水栽培中的首选品种。 相似文献
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Annual Medicago as a Smother Crop in Soybean 总被引：2，自引：0，他引：2
C. C. Sheaffer J. L. Gunsolus J. Grimsbo Jewett S. H. Lee 《Journal of Agronomy and Crop Science》2002,188(6):408-416
Use of conservation tillage and narrow row spacing in soybean [Glycine max (L.) Merr.] production has led to increased use of herbicides for weed control. Some producers are seeking alternative weed control methods, such as smother crops, that would reduce dependence on chemical weed control. A successful smother crop must compete strongly with weeds but minimally with the crop. In four environments, we intercropped three annual Medicago spp. (medics) with soybean to test their utility as a smother crop for weed control. Annual medics were intercropped with soybean at rates of 0, 85, 258, or 775 seeds m?2, and the intercrops were grown with and without weed control. Increasing medic seeding rate decreased weed yields but also reduced soybean herbage and grain yields. For the weed‐controlled treatment, average soybean grain yields declined 7 kg ha?1 for every 10 seeds m?2 increase in medic seeding rate. Soybean grain yield was lower when grown with Medicago scutellata L. cv. Sava than when grown with Medicago polymorpha L. cv. Santiago or Medicago lupilina L. cv. George. Soybean grain yield was negatively related (r=?81) to medic herbage production. In the autumn following soybean harvest, medic residue ranged from 200 to 3700 kg ha?1 depending on the location and seeding rate. Medics provided residue for soil protection, suppressed weeds, but also reduced soybean yields. 相似文献
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P. M. Dempsey C. C. Shock W. A. Williams R. M. Carlson 《Journal of Agronomy and Crop Science》1988,161(5):295-299
The uptake kinetics of nitrate and ammonium ions was compared for the annual range species: subclover ( Trifolium subterraneum L.), soft chess ( Bromus mollis L.), and broadleaved filaree ( Erodium botrys [Cav.] Bertol.) to study competitive interactions in nitrogen deficient soils. Fifteen-day-old seedlings were allowed to deplete solutions of nitrate or ammonium in the range of 5 to 500 μM concentrations for a 10-hour period during which net uptake (depletion) was monitored by a sensitive conductance technique. Subclover uptake rates were markedly less than those for soft chess and filaree for both nitrate and ammonium at both low and high concentrations. The evidence supports the hypothesis that subclover is a poor competitor for soil N in part because of this physiological difference. 相似文献
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为明确不同轮作模式下耕作层土壤微生物群落的变化,揭示水旱轮作有益于蔬菜可持续生产的潜在机理。本文设计4种常见的轮作模式,在同一地理区域固定试验田块进行长期轮作试验,并利用高通量测序技术测定土壤中真菌的ITS1区域序列和细菌的16S rDNA的V3-V4可变区序列,进行土壤微生物多样性分析。结果表明：Alpha多样性分析表明,在4种周年轮作模式下,耕作层土壤真菌群落多样性发生了显著变化,水旱轮作模式(SH)的Shannon指数显著高于嫁接模式(JJ)和蔬菜轮作LZ模式(LZ)的,而与蔬菜轮作LD模式(LD)的无显著差异。耕作层土壤细菌群落多样性和丰富度均发生显著变化,SH模式的Shannon指数和ACE指数均显著高于LD模式的,且SH模式的Shannon指数显著高于其他模式的。主坐标分析表明,4种周年轮作模式间,耕作层土壤微生物群落发生显著分化,SH模式和LZ模式均各自成组,JJ模式与LD模式聚为一组。组间物种差异显著性分析表明,SH模式有7个属真菌和26个属细菌的丰富度显著高于其他模式的,LD和LZ模式分别有4个属真菌和7个属细菌的丰富度显著高于其他模式的,JJ模式只有1个属细菌的丰富度显著高于其他模式的。不同轮作模式长期周年轮作下耕作层土壤微生物群落发生了显著变化。长期水旱轮作提高了土壤微生物群落多样性,增加了有益菌种类和相对丰度,更有利于蔬菜可持续生产。 相似文献