共查询到13条相似文献,搜索用时 78 毫秒
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为探索低换水量的对虾养殖生产方式,该研究构建了一种简易式工厂化对虾养殖系统,试验组利用自行研发的蛋白分离器和新型集污盘去除系统总悬浮颗粒物和老化微藻,对照组不设置蛋白分离器和集污盘,进行对虾养殖和水质调控试验,结果表明:试验组平均总氨氮浓度、平均亚硝氮浓度、平均TSS(Total Suspended Solids)浓度、平均副溶血弧菌数量分别为(0.4±0.16)、(0.53±0.23)、(68.33±39.72)mg/L和(140±113.83)cfu/mL,显著低于对照组(0.96±0.62)、(1.17±0.59)、(147.14±94.18)mg/L和(661.34±473.96)cfu/mL(P<0.05);试验组成活率及单位产量分别为82.62%±5.64%和(3.44±0.85)kg/m3,显著高于对照组18.29%±4.63%和(1.09±0.23)kg/m3(P<0.05)。该研究构建的简易式循环水工厂化系统,设置蛋白分离器流量10 m3/h且不间断运行,养殖前45 d不换水、后55 d利用... 相似文献
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微生物是鱼类循环水养殖系统(Recirculating aquaculture system,RAS)的重要组成部分,与循环系统的水质情况及养殖动物的健康状况密切相关.为分析和研究循环水系统中细菌群落与养殖动物健康之间的关系,总结了现有报道中关于海水鱼循环水养殖系统的细菌群落结构研究进展,主要分析不同系统中养殖动物、生... 相似文献
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结合既有的文献资料分析马铃薯种薯繁育中基质的应用进展,论述了无土栽培基质的主要作用和应用优势,对于有机基质、无机基质和复合基质的特性做了具体分析,并研究了基质在马铃薯种薯繁育中的具体应用. 相似文献
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杂交水稻机械化种子生产技术的研究进展 总被引:1,自引:4,他引:1
该文回顾分析了国内外杂交水稻制种技术的发展概况,提出中国杂交水稻种子生产技术经历了杂交水稻制种繁种的经验摸索和积累阶段(1973~1980年)、杂交水稻制(繁)种的技术提高和完善阶段(1981~1990年)和杂交水稻制(繁)种的超高产技术研究与推广阶段(1991~至今)等3个发展阶段;国外杂交水稻大面积推广应用与与制种技术研究还在进行之中。认为要提高中国杂交水稻种子质量和种子生产效益及种子生产技术竞争力,今后必须应用推广杂交水稻机械化种子生产技术。至今已进行了除草剂敏感基因导入父本法、抗除草剂基因导入母本法和稻壳颜色标记法的杂交水稻混播机械化制种技术;杂交水稻机械采粉贮粉与授粉制种技术;利用雌性不育系的机械制种技术等。其中杂交水稻混播机械化制种技术已获得小面积成功应用,其余方法还在试验与研究之中。因此,今后需要水稻育种家与农机专家密切合作,进一步深入开展杂交水稻机械化制种技术的研究及推广应用工作。 相似文献
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Niels P. A. Peeters Ian R. Willick Ruud H. M. Nabben Doug R. Waterer Tamara M. O. Verhoeven 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2020,70(3):224-232
ABSTRACTThis study examined if dwarf French bean (Phaseolus vulgaris L.) grown at northern latitudes develop seeds with superior yielding potential compared with plants grown at more southern latitudes. Two lines (BND3085 and BND3106) were grown at four sites across latitudes ranging from 52°N to 3°S. BND3085 and BND3106 seeds from Saskatoon grown plants (52°N) had the least damaged seed coats but the highest degree of electrolyte leakage from the seed and the lowest maximum germination rates. The Saskatoon (BND3085 and BND3106) and Nunhem (BND3106) seed lots had the lowest maximum germination rates when germinated at 28°C, 12°C, or when exposed to saline (100?mM NaCl) conditions. Saskatoon BND3085 seed produced plants with the lowest aboveground vegetative and total seed dry matter as well as the lowest pod number per plant. In contrast, plants grown from Saskatoon BND3106 seed produced 1.5-fold more total pods, 1.3-fold more total pods and 1.4-fold higher seed dry matter per plant as compared to plants grown from the Nunhem (51°N) or Arusha seed sources. This resulted in a 2.4–4.5% higher harvest index. These results suggest cultivar-specific dwarf French bean seed propagation at more northern sites may increase the productivity of the resulting crop. 相似文献
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为了揭示茶叶籽贮藏时间对发酵法茶叶籽毛油产率与质量的影响,每2周从贮藏的茶叶籽中取样,利用茶叶籽油发酵法生产工艺进行茶叶籽毛油生产,并对工艺中各项剩余物的含油量及毛油的重要质量指标进行了测定,结果如下。室温条件下,茶叶籽贮藏47周后,毛油产率下降了23.5%、酸值及过氧化值分别升高了44.88%及69.4%,毛油色泽基本没有变化。滤渣、发酵沉淀的质量分别升高了20.27%及23.35%;淀粉、油渣质量分别降低了6.13%及3.64%。滤渣、发酵沉淀、淀粉及油渣含油率分别升高了15.63%、22.77%、206%及12.88%。发酵沉淀质量对毛油产率的影响是正向的,淀粉、油渣及滤渣质量对毛油产率的影响是负向的;发酵沉淀及滤渣含油率对毛油产率的影响是正向的,淀粉及油渣含油量对毛油产率的影响是负向的,影响大小的排序为:油渣淀粉滤渣发酵沉淀。综合分析表明,滤渣是通过滤渣质量的增加导致毛油产率随贮藏时间下降的,其下降作用的贡献占全部下降因素的79.28%。贮藏47周后的茶叶籽仁,利用发酵法生产工艺仍然具有毛油生产价值。该研究可为茶叶籽油合理生产提供理论支撑。 相似文献
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Semiha Cecen Ayse Karaca 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(1):77-81
Abstract This study was conducted to determine the effects of honeybee (Apis mellifera L.) and bumblebee (Bombus terrestris L . ) on alfalfa (Medicago sativa L.) seed production in the west Mediterranean region of Turkey, between 2001 and 2003. The experimental plots (4×3 m) were arranged in a randomized complete block design with three replications for spring and autumn seasons. Four pollination treatments (caged with bumblebee (BP), caged with honeybee (HP), open-pollinated (OP) and pollinator excluded (EP)) were applied. The effects of honeybee and bumblebee on alfalfa seed yield, number of pods per raceme, number of seeds per pod, and podding rate were investigated. The results of seed yield indicate that interaction between treatment groups and seasons was significant (p<0.01). The highest seed yield in alfalfa was found in OP (66.19kg/ha) in the spring followed by BP (56.48kg/ha), HP (49.20kg/ha) and EP (2.44kg/ha). With regarding to the autumn season, the highest seed yield was found in BP (26.17kg/ha) treatment followed by HP (22.89kg/ha), OP (18.12kg/ha) and EP (1.96kg/ha). The results of this research show that B. terrestris can be recommended as an alternative pollinator to honeybee for alfalfa seed production. 相似文献
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为探究适宜肉牛生长的最佳饲养密度,提高肉牛场经济效益,该文研究了饲养密度对肉牛生产性能,行为活动及经济效益的影响.在江西省高安市肉牛试验站选取体质量182~282 kg的杂交牛,在固定圈舍面积(18 m2)内分别饲养3、4、5、6、9头肉牛,对应占地面积为6.0、4.5、3.6、3.0、2.0 m2/头,饲养密度依次增加.由于肉牛体型较大,每个处理2个重复.结果显示,2.0 m2/头的试验组每头牛日采食量为11.90 kg显著高于其他处理组(P<0.05),但每头牛日增质量仅为1.09 kg;3.6 m2/头时,每头牛日采食量处于居中水平为10.96 kg,每头牛日增质量最佳,达到1.41 kg.随着饲养密度的增加,舍内二氧化碳浓度分别为1056.38、1108.44、1172.65、1200.89、1398.19 mg/m3,呈上升趋势;占地面积为2.0 m2/头时,舍内氨气浓度最高达3.23 mg/m3,而6.0 m2/头时仅为1.13 mg/m3;不同处理组之间有害气体浓度存在显著性差异(P<0.05).2.0 m2/头处理组1 d内站立时间(含打斗)为11.84 h,站立时间最长,脏污程度评分为2.09,体表最脏,3.6 m2/头试验组在打斗时间及体表清洁度方面均处于居中水平.综合上述指标,182~282 kg的每头牛适宜占地面积为3.6 m2,此时饲料转化率高,动物福利水平较好,利于农场取得较好经济效益. 相似文献
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Organic seed is the basic for organic agriculture, since it is a crucial link in the chain from research, breeding, seed production, to organic production. With organic seeds the grower can complete the chain of organic input. To develop an organic foliar spray technique and for organic seed production, experiments were carried out to study the effect of organic foliar spray with pulse sprout extract on rice. In this study, horse gram and cowpea, the unexploited legumes of the tropics with high nutritional quality and comparatively low cost were used for preparing the pulse sprout extracts, an organic foliar spraying material. Higher accumulation of bioactive substances in sprouted seeds offers immense scope to develop an inexpensive and effective organic foliar spray technology so as to achieve better crop growth and higher seed yield of rice, the major staple food of the world. The biochemical analysis was done in both extracts to estimate the total antioxidants activity, soluble protein content, total soluble sugars, ascorbic acid content and minerals like nitrogen, phosphorus, potassium, calcium, iron and zinc. Subsequently, the effect of pulse sprout extract spray in improving crop growth, tillering, productivity, and resultant seed quality of was studied by spraying on the parental lines of rice hybrid CORH3 (A, B and R lines) and rice variety CR 1009. The experiment consisted of four trials. In the first trial, four concentrations of pulse extract (1, 2, 3, and 4%) were evaluated in the R line (medium duration variety) of CORH3 (medium duration). In the subsequent trials, the best concentrations (2 and 3% for horse gram and 1 and 2% for cowpea), determined from the first trial, were evaluated again in two medium duration lines of B line multiplication (AXB) and hybrid seed production (AxR). The fourth trial was done with a long duration variety namely CR 1009. Spraying of pulse sprout extract significantly improved majority of the growth and yield attributes culminating in significantly higher seed yield, in all the four trials. The study firmly revealed foliar sprays with either 3% horse gram sprout extracts or 2% cow pea sprout extract during active tillering and seed filling stages of rice crop, can significantly increase the growth and yield attributes, eventually resulting in higher seed yield, irrespective of the cultivars. It could be concluded that foliar spraying of 3% horse gram sprout extract or 2% cow pea sprout extract at active tillering stage and seed filling enhances seed yield attributes and yield in rice. 相似文献
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制种玉米种子乳线发育的水氮效应 总被引:2,自引:0,他引:2
乳线是判定玉米成熟度的重要指标之一,为明确灌水和施氮对制种玉米种子乳线发育的影响,以‘郑单958’和‘先玉335’制种玉米为研究对象,设置充分灌溉(6 000 m3·hm?2,W6000)、中度胁迫(4 500 m3·hm?2,W4500)、重度胁迫(3 000 m3·hm?2,W3000)3个灌水梯度,不施氮[0 kg(N)·hm?2,N0]、中氮[225 kg(N)·hm?2,N225]、高氮[450 kg(N)·hm?2,N450]3个施氮水平,研究不同水氮应用对制种玉米种子乳线发育进程、籽粒含水量、百粒重、籽粒脱水和灌浆速率的影响。结果表明,不同制种组合在不同水氮条件下种子乳线发育表现出明显差异;不同水氮条件下‘郑单958’乳线发育进程历时18~24 d,较‘先玉335’的33~36 d短;随灌水量增加,‘郑单958’种子乳线发育有延迟趋势,而‘先玉335’种子乳线受灌水量影响不显著;在乳线同一发育阶段,灌水和施氮均对籽粒含水量无显著影响,百粒重均表现为施氮处理显著高于不施氮;不同灌水处理间,‘郑单958’种子在重度胁迫条件下的脱水速率显著高于中度胁迫和充分灌溉,施氮量间无显著差异,‘先玉335’种子脱水速率各灌水量间无显著差异;‘郑单958’种子的灌浆速率各灌水处理间无显著差异,充分灌水条件下,不施氮处理灌浆速率显著高于施氮处理,而‘先玉335’灌浆速率随灌水量增加而增加,同一灌水条件下均是中氮处理高于不施氮和高氮处理;‘郑单958’种子每脱水1%,籽粒百粒重增加幅度在0.37~0.88 g,而‘先玉335’在0.43~1.34 g。因此,‘郑单958’种子乳线发育受灌水影响显著,水分亏缺致使种子脱水加速,乳线进程加快;‘先玉335’种子乳线发育受氮素影响显著,氮素不足和过量均影响种子灌浆,延迟乳线发育。 相似文献
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本研究从基质原料选材、前处理措施,混合基质配比、养分提供,栽培基质的科学使用等方面重点介绍了我国无土栽培基质的新研究成果和应用方法,阐述了我国蔬菜无土栽培基质的研究与应用概况及发展趋势。 相似文献
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氧化亚氮(N_2O)是一种重要的痕量温室气体,对全球气温升高和酸雨形成起着重要作用,并对臭氧层造成严重损害。水产养殖是N_2O的潜在释放源,该研究以中国东南沿海的闽江河口湿地围垦养虾塘为研究对象,采用过程抑制法,通过室内培养试验区分N_2O不同产生过程及其对沉积物N_2O总产生速率的贡献,在此基础上分析沉积物理化性质对N_2O产生的影响。结果表明:养虾塘沉积物N_2O总产生速率在养殖初期、中期和末期的均值分别为1.80、5.95和8.70 nmol/(kg·h),其中硝化作用、反硝化作用、硝化细菌反硝化作用和非生物作用的贡献率均值分别为-162.04%、327.52%、-239.45%和90.27%,从而得出结论:反硝化作用和非生物作用是产生沉积物N_2O的主要来源,硝化作用和硝化细菌反硝化作用则对沉积物N_2O的产生有所削弱;养虾塘沉积物N_2O总产生速率在高温低盐条件下最大,在低温高盐条件下出现最小值,总体呈现随着温度升高而增加,随着盐度升高而降低的趋势;相关分析表明N_2O总产生速率与总碳(total carbon,TC)、土壤有机碳(soil organiccarbon,SOC)、NH4+-N含量和C∶N比均呈显著正相关关系,而在其不同产生过程中仅有非生物过程受到TC、SOC含量的显著影响。 相似文献