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芝麻吸钾特点与施用钾肥技术的研究 总被引：1，自引：0，他引：1
１９８６～１９８９年在河南省芝麻主要产区布置了田间试验。结果表明，每生产１００ｋｇ芝麻种子需要钾素（Ｋ２Ｏ）６．２４～６．６８ｋｇ。不同生育阶段吸收钾素的比例相差很大，钾肥的增产效果也因年份不同而异。缺钾土壤，其速效钾含量低于１２μｇｇ－１，每公顷施用Ｋ２Ｏ１０５～１２０ｋｇ作基肥，可获得最大增产效益。 相似文献
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本文将芝麻历史产量分解为趋势产量与气象产量两个分量,并将气象产量变换为气象产量指数,通过多重非线性回归模拟,建立了气象产量指数及产量模式,从而揭示芝麻产量动态趋势及年际变化原因。其结果,可用于鉴定芝麻生育期间的农业气候条件,为芝麻趋利避害与高产稳产提供依据,并可用于产量的预测预报。 本文采用安徽淮北平原阜阳县历年芝麻单产及相应年份的气象资料。五十年代,由于春、夏芝麻并行,六十年代起以夏芝麻为主,故五十年代产量资料舍去不用。现将研究结果分述如下: 相似文献
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调查表明，湖南芝麻种质资源以夏芝麻、全生育期９０ｄ左右、单杆型、四棱中等长度蒴果，每叶腋花数为三花、多或中等茸毛量、白色种皮、中等耐旱的裂蒴品种为主。 相似文献
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芝麻核心种质与非核心的同工酶研究 总被引：2，自引：1，他引：1
采用聚丙烯酰胺凝胶垂直平板电泳技术，对选自中国芝麻资源７个生态区的３６个地方品种进行了酯酶，过氧化物酶，苹果酸脱氢酶，６－磷酸葡萄糖脱氢酶，淀粉酶５种同工酶分析，仅酯酶酶谱表现出品种间和品种内的多样性差异。对芝麻核心种质和非核心种质中各９个品种的１０８０个植株酯酶同工酶分析，结果表明在迁移率Ｒｆ０．４５－０．６７间检测到８种酶谱类型。通过对核心种质与核心种质的酯酶酶谱类型和酶带分布频率，品种多样性 相似文献
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利用2020年度山东省济南市济阳区夏玉米全生育期的观测资料,与常年、上年相应气象指标进行比较,分析夏玉米生育期间有利和不利的气象条件,评价气象条件对夏玉米生长发育和产量的影响.结果表明:在播种—拔节期,光温适宜,降水偏少,造墒播种弥补了降水的不足,夏玉米出苗良好,苗期降水偏少利于夏玉米蹲苗和根系下扎;在拔节—开花期,气象条件更对夏玉米生长利大于弊;在开花—成熟期,光温适宜,降水适中,对夏玉米灌浆非常有利.总体而言,济阳区2020年夏玉米全生育期气象条件对产量的影响利大于弊,气候年景属于平偏丰年.对2021年夏玉米整个生长期的气候进行了预测:济阳区2021年夏玉米生长期间,降水较常年偏多1～2成,气温较常年偏高0.5℃左右,光、温、水匹配较好,预测气候年景为平偏丰年. 相似文献
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芝麻不同时期去叶对蒴果发育和产量的影响及保叶增产措施 总被引：5，自引：2，他引：5
采用定株观察，以芝麻生长正常单株为对照，研究不同生育时期，不同蒴果发育时期去叶，对芝麻农艺性状和单株产量的影响。结果表明，随着芝麻生育进程，终花期，封顶期，盛花期去叶减产值幅度递增。相同植株同天开花采取不同时期去叶所结蒴果分别与对照相比，去叶时间越早秕籽率越高，千粒重越低。同时还进一步研究出延长芝麻中上部叶片功能期，提高单株产量的技术措施。 相似文献
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华北春芝麻不同栽培条件对干物质的影响 总被引：4，自引：0，他引：4
对华北春芝麻区不同栽培条件下芝麻干物质的积累、分配、转移规律进行了研究，结果表明：(1)芝麻生殖器官干重与总干物质变化一致，随生育进程而增加；(2)干物质分配，苗期以营养器官为主，蕾期、花期营养器官与生殖器官并进，以后叶片中的干物质越来越多地转移到生殖器官；(3)封顶期叶片仍保持一定的绿叶面积，能继续供给生殖器官干物质；(4)地膜覆盖比露地栽培更有利于干物质的积累、分配、转移；(5)探讨了高产生理指标。 相似文献
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为探讨内源激素在高秆和矮秆芝麻株高建成中的含量变化特征及其与株高生长速率间的关系,以株高差异显著的2个高秆和2个矮秆芝麻为材料,用液相色谱-串联质谱法(LC-MS/MS)测定相同种植条件下不同生育阶段茎尖和倒三叶内3种激素(生长素IAA、赤霉素GA3和脱落酸ABA)含量。分析发现:从3对真叶期到终花期高/矮秆芝麻株高持续增高,但高秆基因型日均生长速率始终高于矮秆基因型;高/矮秆芝麻株高构建的不同发育阶段,叶片IAA和茎尖GA3含量变化具有较明显差异;ABA含量在高/矮秆芝麻间无明显规律,但在矮秆基因型ZZM2748中表现出一个明显特征,即叶片和茎尖中均在初花后20d含量明显高于其它基因型。从3种内源激素与生长速率相关性分析看出,茎尖中GA3含量与株高生长最为密切。 相似文献
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江汉平原油菜根肿病流行规律及栽培应对措施 总被引：1，自引：0，他引：1
以枝江市问安镇龚桥村为例,采用普查和抽查方法,研究2008-2017十年间江汉平原油菜根肿病流行规律,分析土壤条件、栽培措施等因素对其爆发的影响。在前期研究基础上,采用随机区组设计方法开展无病苗分期播种移栽、苗床消毒、根际施肥用药等田间试验,优化防治技术。调查结果表明,江汉平原油菜根肿病扩散蔓延速度快,3～5年内连片发作,危害严重;机械作业是该病远距离传播扩散的主要原因,土壤酸化是其流行爆发的基础。田间试验结果表明,培育无病苗后移栽到病田避病效果明显,菜籽产量损失小,9 月中下旬育苗,10月中下旬移栽,重病田块能获得2 500 kg / hm2左右的正常产量;根际施用氰氨化钙和氰霜唑显著降低根肿病病情指数,防效分别为50%、90%,两者同时施用防效达100%;苗床氰氨化钙焖棚、火土灭菌、氟啶胺、氰霜唑淋土防治效果分别为100%、96%、76%、62%。基于江汉平原地区水稻土对根肿病极度敏感,在农业机械化生产的背景下,提出油菜根肿病防控应以预防为主。为了减少防治成本,提高防治效果,建议可将氰氨化钙等碱性钙肥丸粒化,作为种肥和底肥集中施用于根际周围;在此基础上无病和轻病田用氰霜唑种子包衣后直播,重病田块用氟啶胺进行苗床消毒,培育无病苗后移栽。 相似文献
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《Plant Production Science》2013,16(3):269-278
AbstractA greenhouse experiment was conducted to study the adaptive mechanism of cotton and peanut under water stress conditions. Five cultivars of cotton and six cultivars of peanut were grown in pots under two water levels; the control and water stress condition, where irrigation water equal to 100% and 50% of the daily transpiration, respectively, was daily applied. Peanut showed a greater increase than cotton in leaf temperature (Tl) and non-photochemical quenching (NPQ) and a greater decrease in water content per unit leaf area (WCLA), chlorophyll content and maximum quantum yield of photosystem II (PSII) (Fv/Fm) in the water stress condition. On the other hand, the water stress lowered the transpiration rate, actual quantum yield of PSII (ΔF/F’m) and leaf area (LA) more in cotton than in peanut. Cotton showed greater reduction in LA along with little reduction in the root dry weight (RDW) leading to high WCLA, while peanut showed increased RDW with little reduction in LA under the water stress condition. It was concluded that photodamage and down regulation in PSII were induced by water stress, coinciding with increases in leaf temperature regulated mainly by transpiration. Peanut showed more severe photodamage in PSII than cotton under the water stress condition. 相似文献
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对广西南宁市郊芒果园内及其附近空旷地的气象要素进行对比观测。结果表明:①芒果园内的日平均光照度为7 528 lx,占空旷地的28.66％;②果园内日平均气温及日较差依次为23.5℃和5.6℃,相应比空旷地的低0.6℃和0.3℃;③果园内土壤浅层(0-20 cm)日平均温度为22.0-23.5℃,比空旷地的低2.0-3.6℃;④果园内日平均相对湿度为80％,比空旷地的高5％;⑤果园内日均风速为0.16 m/s,占空旷地的14.3％。通过计算机模拟,筛选出果园内外主要气象要素的最佳预测模型。 相似文献
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湖北省油菜种植风险的区划研究 总被引：1，自引：0，他引：1
本文选取能概括湖北省油菜种植风险的单产减产10%、20%的概率、单产变异系数、专业化指数、效率指数、旱涝保收指数、水利投入指数、温度距平值、旱灾涝灾指数9个指标,使用系统聚类方法,以湖北省各县油菜种植面临的种植风险不相同的实际情况为依据,对湖北省78个县的油菜种植划分出4个风险等级,发现湖北省油菜种植高风险区集中在湖北省西北部及北部地区,较高风险地区集中在湖北西部、西南部、以及西北部和北部地区部分地区,中等风险的地区集中在江汉平原,低风险区集中在湖北东北部、东南部和西南部分地区。根据研究结果提出对不同风险地区实行有针对性的油菜生产促进措施;完善湖北省油菜种植生产布局;发展油菜保险,实行差别费率三点建议。 相似文献
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A study on evapotranspiration from potato fields was conducted in the Lower Gangetic Plains of India. The input data required for the CROPWAT irrigation management model was collected, and evapotranspiration (ET) and irrigation water requirement (IWR) for potato crops were calculated using the model. Firstly, the CROPWAT model was validated by comparing simulated crop evapotranspiration (SET) with actual ET calculated through the field water balance method. Thereafter, SET and IWR for nine locations in the lower Gangetic plains of India were calculated for the period from 1996–1997 to 2008–2009, for the current situation (using 20-year-average weather data of the stations), and for elevated thermal conditions, i.e. considering 2 and 3 °C increases over the current temperature. The future change in IWR for potato up to 2050 was also calculated considering the projected climatic scenario generated by the PRECIS model. The CROPWAT calculated IWR values showed an increasing, though not statistically significant, trend in requirement of irrigation water for potato across the nine locations during the period from 1996–1997 to 2008–2009. At a temperature increase of 2 °C over normal, the mean SET of potato would increase by 0.06 mm per day and the average IWR would be 6.0 mm per season more. If the mean temperature would be 3 °C more than normal, the SET would be 0.16 mm day?1 higher and the IWR 16.6 mm. Also based on the projected climatic scenario generated by the PRECIS model, the future SET up to 2050 showed an increasing trend. The present study indicates increasing demand for irrigation water, which may significantly affect the agricultural scenario in the region. 相似文献
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Potato growth with and without plastic mulch in two typical regions of Northern China 总被引：2，自引：0，他引：2
Plastic film mulching is an important agricultural practice to save water and improve crop productivity in Northern China. Three field experiments were conducted to examine the effect of plastic mulch on soil temperature, potato (Solanum tuberosum L.) growth and evapotranspiration under drip irrigation in two typical regions of Northern China in 2001 and 2006. Results suggest that daily mean soil temperature under mulch was 2–9 °C higher than without mulch, especially during the early growth. Potato growth was restrained under mulching conditions in the North China Plain mainly due to the higher air temperature in this region and thus the higher soil temperature. The negative effects of mulching included a lower emergence and fewer marketable tubers per plant. Evapotranspiration and potato tuber yield were both reduced by mulch, especially in the North China Plain. In northwest China, mulch favorably increased the weight of jumbo tubers (W ≥ 300 g) per plant. Mulching duration had little effect on potato evapotranspiration in northwest China. However, both tuber yield and water use efficiency (WUE) decreased with increases in mulch duration, which suggests the plastic mulch should be removed early. 相似文献
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《Journal of Crop Improvement》2013,27(2):37-70
Summary Atmospheric carbon dioxide (CO2) concentration has risen from about 270 mmol (CO2) mol?1 (air) (i.e., mole fraction of dry atmospheric air basis) before 1700 to about 370 mmol mol ?1 currently. General Circulation Models (GCM) have predicted a global temperature rise of 2.8 to 5.2°C for a doubling of CO2. This review examines evapotranspiration and water-use efficiency responses of plants to rising CO2 and climatic changes, especially temperature. Doubling of CO2 will decrease leaf stomatal conductance to water vapor about 40%. However, water use by C3 crop plants under field conditions has usually been decreased only 12% or less for two reasons. Firstly, feedbacks in the energy balance of plant foliage cause leaf temperatures to rise as stomatal conductance is decreased. Increases of leaf temperature raise the vapor pressure of water inside the leaf, which increases the leaf-to-air vapor pressure difference. This increased driving force for transpiration offsets in large part the decreased leaf conductance caused by elevated CO2. Secondly, CO2 enrichment tends to cause leaf area to increase more rapidly in many crops. This increased leaf surface area for transpiration also offsets part of the decreased stomatal conductance per unit leaf area on the whole canopy evapotranspiration, but the energy budget feedbacks are more important. Experiments point to a yield enhancement of 30 to 35% for C3 crops for the direct effects a doubling of CO2 (without ancillary climate change). If temperature rises, this yield enhancement may be greater for vegetative growth but less for seed grain yield. Experiments on both ambient and elevated CO2 treatments in sunlit growth chambers showed that transpiration rates increased 20% when air temperature was changed from 28 to 33 °C and increased 30% when temperature was increased from 28 to 35 °C. Thus, under well-watered conditions, evapotranspiration will increase about 4 to 5% per 1°C rise in temperature. Crop model predictions of yields of soybean and maize showed a reduction due to temperature increases by two GCM models. Under Southeastern USA conditions, doubling CO2 in the Goddard Institute for Space Studies (GISS) climate change scenario resulted in an 12% increase in yields, but yields decreased 50% in the Geophysical Fluids Dynamics Laboratory (GFDL) climate change scenario. Optimum irrigation for both models gave yield increases of about 10%. These model results illustrate the critical requirement of water for production of crops. Under rainfed conditions, crop yields could suffer tremendously if growing season precipitation is decreased, but yields could increase moderately if growing season precipitation is increased. Under the high growing season rainfall scenario (GISS), irrigation requirements for optimum soil water were increased 22%, but under the low rainfall scenario (GFDL), irrigation requirements were increased 111%. Without the effects of climate change, rising CO2 will cause an increase in crop water-use efficiency (WUE). Most of the increases in WUE will be due to increases in dry matter, with little or no contribution from decreases in water use per unit land area. Growers could produce higher yields per unit land area with higher total production, or maintain the same total production with less land and less total water use. However, if temperatures rise, transpirational water use will increase, and WUE will decline. Higher temperatures, and especially less rainfall, would raise the irrigation requirements of crops. Competition for water resources from other uses could result in less water available for irrigation. 相似文献
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气候变化对福建省牧草气候生产潜力的影响 总被引：2，自引：0，他引：2
以福建省为研究区域,研究牧草生产力与气候条件的关系及其对气候变化的响应.结果表明,近50a来,福建省气温呈现升高趋势,平均每10 a升高0.2℃;年降水量变化总体上呈不显著的增加态势;牧草气候生产潜力随年代的变化呈先减后增的趋势;空间上以厦门地区最高,三明地区最低.降水量对福建省牧草气候生产潜力的影响明显高于气温.若未来温度每降低1℃,降水减少1 mm时,牧草气候生产潜力分别降低318.3 kg·hm~(-2)·a~(-1)和22.7 kg·hm~(-2)a~(-1). 相似文献
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过湿条件下大豆不定根的发生及其生理作用研究 总被引：1，自引：0，他引：1
大豆是实行水旱轮作的重要作物之一,在缺乏良好排水条件的水田中实行水旱轮作时,长期涝渍所致的伤害成为大豆生长不良及产量低的重要原因.通过盆栽和大田试验在大豆生育初期进行过湿处理,调查培土或无培土条件下不定根的发生情况,揭示不定根对伤流速度,氮素的吸收运转等的影响,讨论了不定根与大豆耐湿性的关系.淹水条件下培土对不定根及根瘤的发生产生较大的影响,淹水条件下发生的不定根的量占总根重的43.1%,这些不定根提供了81.4%的伤流速度.不定根的呼吸速度为2.61 mg CO2g-1h-1,是初生根的近3倍.淹水导致全叶位叶片的叶色变淡,不定根的发生改变了伤流液中不同形态氮素的组成和全氮含量,可使下位叶的叶色维持较高水平.淹水条件下大豆的冠根比比对照小.不定根取代了受涝渍伤害而失去功能的初生根的作用,积极地进行养分和水的吸收,确保了涝渍逆境下物质生产的顺利进行. 相似文献