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991.
甜菜氮肥的合理施用 总被引:3,自引:0,他引:3
综述文献关于氮肥对甜菜的生长、吸收分配规律、生理生化及产质量的影响可知,甜菜生长需要多种营养元素,其中氮素尤为重要,不合理施用氮肥对甜菜的产质量带来很多负面影响;造成资源浪费、环境污染,影响人类健康。提出合理施氮、用氮的途径与策略:第一,因地、因品种、因时制宜,根据测土资料及不同甜菜基因型差异确定施肥种类、配比;根据作物不同生长时期的需肥规律及不同生态条件需要,按需供肥。第二,肥要在水的作用下才能发挥作用、才能更好发挥作用,区域配肥技术与灌溉技术相结合的水肥一体化精准精细灌水施肥技术是甜菜生产高效用肥的必然发展趋势。第三,作物不同养分间具有协同和相互影响作用,因此根据同等重要原则应有机配比。第四,为了提高肥效及利用率,施用缓控释肥,有机无机肥配施,施用微生物肥、生态肥等发挥微生物的促进、协同作用。第五,常规育种与转基因技术结合培育氮素养分高效利用品种。第六,利用现代监测技术手段及应用甜菜生长模型尤其是CERES-Beet模型监测氮等养分的转化、吸收等动态。 相似文献
992.
内蒙古甜菜制糖产业发展探析 总被引:3,自引:0,他引:3
内蒙古自治区从1955年包头糖厂建成投产开始,已成为我国重要的甜菜制糖产业基地。近年来内蒙古甜菜制糖产业快速发展,甜菜制糖企业呈现集团化、多元化、专业化的格局,共有13家糖厂在生产,日加工甜菜能力达5.35万吨,食糖年产能70万吨。内蒙古具有较强的甜菜生产技术优势,甜菜种植的比较收益突出,通过甜菜制糖企业合理布局,建立甜菜种植保护区,依靠科学技术,规模化种植提高了甜菜生产机械化水平,合理轮作,避免甜菜重迎茬,建立环境友好型甜菜生产方式,形成稳定的甜菜生产能力,为制糖企业提供充足原料。采用先进的制糖工艺技术,降低糖分工艺损失,加快新产品开发,延伸甜菜制糖产业链,以效益为中心,推动甜菜制糖行业可持续发展。2018/2019榨季内蒙古食糖产量达到历史高位的65万吨,占国内甜菜糖总产量的49.04%,成为我国最大的甜菜糖产区。 相似文献
993.
994.
大豆体细胞无性系(Clone)的变异与优良品系筛选 总被引:3,自引:0,他引:3
本研究以栽培大豆辽豆85-38γm2、九农15及半野生大豆公野交2246等10个品种为材料,通过茎节培养从辽豆85-38γm2中获得了可以继代2的体细胞无性系并再生植株。不同继低培养世代(SC1、SC2、SC2)的再生植株在株高、叶形、分枝数、百粒重等重要农艺性状上均产生了变异,通过二年的田间产量鉴定与产量比较,从SC2中筛选出4个高产、虫食率低的优良品秒。 相似文献
995.
996.
香草兰营养特性的研究 总被引:6,自引:3,他引:6
对海南不同生产水平的香草兰种植园植株的养分调查分析,及N,P,K,Ca,Mg肥料的盆栽试验,研究香草兰的营养特性。结果表明,香草兰植株养分的吸收量以K〉Ca〉N〉Mg〉P,叶片以Ca〉K〉N〉Mg〉P;结果植株养分吸收量N:P:K:Ca:Mg=1.00:0.24,1.39:1.18:0.48,盆栽幼苗N:P:K:Ca:Mg=1.00:0.10:1.38:1.23:0.33;高产园植株Ca,P含量极 相似文献
997.
假眼小绿叶蝉的生态控制与合理用药 总被引:5,自引:0,他引:5
采用室内观察和田间系统调查相结合的方法,探明了茶园蜘蛛中的跳蛛和管巢蛛是捕食叶蝉的优势类群,其优势种主要为白斑猎蛛、花腹纽蛛、警戒蝇豹、棕管巢蛛、褶管巢蛛,它们的日捕食量在蛛蝉比1∶40的范围内,随猎物密度的增加而增加,其中以蛛蝉比为1∶10—1∶20时,捕食量的增长率最高。茶园蜘蛛的年发生数量消长呈马鞍型,即;春、秋多,夏季少。优乐得是一种治蝉效果好、且能保护天敌的理想农药。田间小区试验和大田对比试验结果表明,合理使用这种农药、并辅之以及时采摘、冬前行间覆盖稻草等农艺措施,能够获得较好的生态控制效果和经 相似文献
998.
Genetic gains in grain yield, net photosynthesis and stomatal conductance achieved in Henan Province of China between 1981 and 2008 总被引:2,自引:0,他引:2
T.C. Zheng X.K. Zhang G.H. YinL.N. Wang Y.L. HanL. Chen F. HuangJ.W. Tang X.C. XiaZ.H. He 《Field Crops Research》2011,122(3):225-233
Knowledge of the changes in agronomic and photosynthetic traits associated with genetic gains in grain yield potential is essential for an improved understanding of yield-limiting factors and for determining future breeding strategies. The objectives of this study were to identify agronomic and photosynthetic traits associated with genetic gains in grain yield of facultative wheat (Triticum aestivum L.) between 1981 and 2008 in Henan Province, the most important wheat producing area in China. During the 2006-2007 and 2007-2008 crop seasons, a yield potential trial comprising 18 leading and new cultivars released between 1981 and 2008 was conducted at two locations, using a completely randomised block design of three replicates. Results showed that average annual genetic gain in grain yield was 0.60% or 51.30 kg ha−1 yr−1, and the significant genetic improvement in grain yield was directly attributed to increased thousand grain weight which also contributed to the significant increase in harvest index. The genetic gains in rates of net photosynthesis at 10, 20 and 30 days after anthesis were 1.10% (R2 = 0.46, P < 0.01), 0.68% (R2 = 0.31, P < 0.05) and 6.77% (R2 = 0.34, P < 0.05), respectively. The rates of net photosynthesis at 10 (r = 0.58, P < 0.05), 20 (r = 0.59, P < 0.05) and 30 (r = 0.65, P < 0.01) days after anthesis were closely and positively correlated with grain yield. A slight decrease in leaf temperature and an increase in stomatal conductance after anthesis were also observed. Grain yield was closely and positively associated with stomatal conductance (r = 0.69, P < 0.01) and transpiration rate (r = 0.63, P < 0.01) at 30 days after anthesis. Therefore, improvement of those traits was the likely basis of increasing grain yield in Henan Province between 1981 and 2008. The genetic improvement in yield was primarily attributed to the utilization of two elite parents Yumai 2 and Zhou 8425B. The future challenge of wheat breeding in this region is to maintain the genetic gain in grain yield and to improve grain quality, without increasing inputs for the wheat-maize double cropping system. 相似文献
999.
目的研究氢化物发生一原子荧光光谱法的同时测定人参中砷和锑的含量。在仪器的最佳工作条件及氢化物发生条件下,还探讨了还原剂及其用量与还原掩蔽剂对测定的影响。方法采用氢化物一原子荧光光谱法进行测定。结果在测定条件下,砷的线性范围为0—10μg/L,r=0.9998,检出限为0.06μg/L,回收率102.3%,精密度(RSD)为3.45%;锑的线性范围为0-10μg/L,r=0.9999,检出限为0.027μg/L,回收率94.7%,精密度(RSD)为4.72%。用该法测定了标准物质茶叶中砷和锑的含量以进行比较,结果与推荐值相吻合。结论方法快速、准确,应用于人参中砷和锑的检测,获得较满意结果。 相似文献
1000.
Xu Gaofeng Shen Shicai Zhang Fudou Zhang Yun Kato-Noguchi Hisashi Roy Clements David 《水稻科学》2018,25(1):32-41
In this study,effects of temperature,light and their interactions on allelopathic effects and the functional traits specific leaf area(SLA)and stem mass fraction(SMF)of different allelopathic potential rice accessions at different growth stages were analyzed.The main results were as follows:Allelopathic responses to temperature and light varied with different allelopathic potential rice accessions at different growth stages.With the rise of temperature and the extension of photoperiod,allelopathic effect increased firstly and then decreased at 2–3 leaf stage,but increased constantly at the 4–5 and 7–8 leaf stages in strong allelopathic rice accessions[O.longistaminata,F1(O.longistaminata×RD23),F2(RL159 and RL169)].Temperature had significant impact on allelopathic effect without considering light factors,but light showed little effect on rice allelopathy at the same temperature conditions.The greatest allelopathic effect was attained with moderate temperature and long photoperiod at 2–3 leaf stage in strong allelopathic rice accessions,but all the rice accessions showed weak allelopathic effects at the low temperature condition(15oC/10oC),and the influence of different factors on allelopathy followed a general trend as temperatureleaf stagelight,indicating that among the multiple factors impacting rice allelopathy,temperature was the main factor.Allelopathic characteristics of F1 and F2 to various temperature and light were similar to O.longistaminata,showing that allelopathic genes from wild rice can be expressed in its descendants.Temperature and light also had significant effects on SLA and SMF,and rice allelopathy was closely correlative to SLA in strong allelopathic rice accessions at the 4–5 and 7–8 leaf stages,but there was no correlation between rice allelopathy and SMF at different growth stages.These results suggested that rice adjust the relationship between allelopathy and SLA and adapt to the varied environments,and that high temperature and long photoperiod can enhance rice allelopathic activity. 相似文献