旱地生态学问题弱解对初值的连续依赖性

随着工业化的发展,人们越来越注重生态环境保护问题.利用能量方法,采用Sobolev不等式研究了旱地生态学问题,得到了旱地生态学问题非负弱解对初值的连续依赖性.     

重金属污染土壤几种生物修复方式比较

土壤重金属污染是全球普遍存在的问题,生物修复因其环境友好且成本效益高而得到广泛关注。但不同生物修复技术有其优势和局限性,充分了解每种修复技术的特点,才能更经济、有效地对污染土壤进行修复。本研究阐述对比了目前的土壤重金属生物修复方法,包括植物修复（植物挥发、植物固定和植物提取）、转基因植物提取、螯合辅助植物修复、微生物辅助植物修复等技术的机制、优势、局限性和适用性等方面的差异。综述提出有效的生物修复技术需要土壤化学、植物生物学、遗传学、微生物学和环境工程等多学科的有机结合。根据污染土壤的特点,结合具有相应改良特性的转基因植物,是实现污染土壤大面积修复的有效方法。同时,农艺措施对天然超级积累植物的生物量和重金属提取能力的刺激作用还需要进一步挖掘。植物修复可以与其他几种传统修复技术有效结合,利用转基因技术建立土壤+植物+微生物的组合是未来修复技术发展的最佳途径。     

牧草产业是我国家兔产业可持续发展的重要支撑

针对我国家兔规模化养殖的快速发展,牧草作为家兔生产主要饲料原料来源,供需矛盾日益突出。本文重点从家兔消化生理特点、兔产品安全生产、农民增收、需求现状与问题等方面进行了论述,并提出了相应对策。     

Association analysis for detecting significant single nucleotide polymorphisms for phosphorus-deficiency tolerance at the seedling stage in soybean [Glycine max (L) Merr.]

Tolerance to low-phosphorus soil is a desirable trait in soybean cultivars. Previous quantitative trait locus (QTL) studies for phosphorus-deficiency tolerance were mainly derived from bi-parental segregating populations and few reports from natural population. The objective of this study was to detect QTLs that regulate phosphorus-deficiency tolerance in soybean using association mapping approach. Phosphorus-deficiency tolerance was evaluated according to five traits (plant shoot height, shoot dry weight, phosphorus concentration, phosphorus acquisition efficiency and use efficiency) comprising a conditional phenotype at the seedling stage. Association mapping of the conditional phenotype detected 19 SNPs including 13 SNPs that were significantly associated with the five traits across two years. A novel cluster of SNPs, including three SNPs that consistently showed significant effects over two years, that associated with more than one trait was detected on chromosome 3. All favorable alleles, which were determined based on the mean of conditional phenotypic values of each trait over the two years, could be pyramided into one cultivar through parental cross combination. The best three cross combinations were predicted with the aim of simultaneously improving phosphorus acquisition efficiency and use efficiency. These results will provide a thorough understanding of the genetic basis of phosphorus deficiency tolerance in soybean.     

温室黄瓜新品种中农33号的选育

中农33号是以自交系09676和12173为父母本配制的黄瓜一代杂种。植株生长势强,耐低温弱光性好。果实商品性好,颜色深绿、有光泽,腰瓜长约35 cm,瓜粗3.4 cm左右,瓜把长约4.5 cm,心腔较小,果肉为淡绿色。白刺、密,瘤小,无棱。高抗WMV,中抗CGMMV、枯萎病、黑星病。早熟性好,持续结果及丰产优势明显。温室长季节栽培每667 m~2产量高达10 000 kg以上。适宜日光温室和春棚栽培。     

长梗润楠扦插生根对IBA、NAA和IAA的响应

长梗润楠(Machilus longipedicellata)是西南地区的特有树种之一,也是优良的绿化树种。以长梗润楠为试材,采用U_7(7~6)方法,研究了IBA、NAA、IAA对长梗润楠扦插生根的影响。结果表明:扦插9个月时,平均愈伤组织产生率、生根率、一级根数、一级根长和一级根直径分别为78.9%~85.6%、84.5%~92.2%、2.7~3.7条·株~-1、9.7~14.6cm和1.22~1.58mm;0.75g·L~(-1) IAA+0.4g·L~(-1) IBA组合的生根率、平均一级根数、一级根直径和根长分别达85.5%、3.5条·株-1、1.58mm和13.5cm,为生根性状综合指标较优的处理组合。穗条的生根率与愈伤组织产生率间呈极显著正相关(P≈0.0000.01),二者的相关模型为Y=26.846+0.629 X(R2=0.506,R2Adj=0.484)。     

香蕉半膜覆盖集成施肥技术效应

为解决香蕉地膜覆盖的科技含量不高,地膜覆盖新技术的应用比较单一等问题,形成集成的综合高产抗旱丰产体系,提高香蕉的高产潜力,在香蕉主产区做香蕉半膜覆盖集成长效肥、有机肥料、测土配方施肥技术田间试验研究。试验表明,香蕉半膜覆盖集成长效肥、测土配方施肥配套技术既固土保水、减少水土流失,又协调土壤的水分和养分,促进水肥互动,提高水肥利用效率;既减少了投入,又增加了作物产量和经济收入,具有推广应用价值。     

开封市公共气象服务发展探讨

公共气象服务是为政府决策、民生发展提供的一项基础性公共事业。该文通过阐述开封市公共气象服务发展的现状,对比国内气象服务工作,分析其中存在的问题,以充分发挥气象服务的社会效益、经济效益。