黄土丘陵区旱地作物水分生态适应性系统评价

根据调查资料和田间试验结果,系统地分析了旱地不同作物生长发育与降水分布的时序关系、旱地作物水分潜在利用率和旱地主要作物水分供需平衡与错位特征,并利用水分生态适应性数学模型,对宁南黄土丘陵区主要作物的水分生态适应性进行了定量评价．结果表明,秋熟作物生长发育与降水分布耦合性较好,夏熟作物生长发育与降水分布耦合性较差．不同作物的降水潜在利用率存在差异。其基本规律是：多年生牧草>薯类作物>谷类作物;秋熟作物>夏熟作物．作物的水分满足率和生态适应性,秋熟作物优于夏熟作物,丰水年份优于干旱年份．旱地6种主要作物的水分生态适应性指数排序依次为：谷子>马铃薯>糜子>胡麻>豌豆>春小麦．     

黄土丘陵区旱地作物水分生态适应性系统评价

根据调查资料和田间试验结果,系统地分析了旱地不同作物生长发育与降水分布的时序关系、旱地作物水分潜在利用率和旱地主要作物水分供需平衡与错位特征,并利用水分生态适应性数学模型,对宁南黄土丘陵区主要作物的水分生态适应性进行了定量评价.结果表明,秋熟作物生长发育与降水分布耦合性较好,夏熟作物生长发育与降水分布耦合性较差.不同作物的降水潜在利用率存在差异,其基本规律是:多年生牧草>薯类作物>谷类作物;秋熟作物>夏熟作物.作物的水分满足率和生态适应性,秋熟作物优于夏熟作物,丰水年份优于干旱年份.旱地6种主要作物的水分生态适应性指数排序依次为:谷子>马铃薯>糜子>胡麻>豌豆>春小麦.     

新一代旱地龙简介

新疆汇通 (集团 )股份有限公司研制的“新一代旱地龙”是一种多功能抗旱营养调节和高效土壤活化剂 ,主要用于各种农作物、蔬菜和园林的叶面喷施及滴灌、渗灌。叶面喷施可以满足植物对各种营养元素的需求 ,提高作物的光合作用和酶的活性 ,促进植物体内氧化还源、增加叶绿素含量、促进新陈代谢、加快细胞分裂分化速度 ,提高植物体内原激素的含量 ,调节糖、酸、维生素的衡定比例 ,使作物具有延缓衰老、保花、保果、复青、高产的作用。“新一代旱地龙”还可促进植物根系对水分和养分的再吸收能力。由于旱地龙内含高活性黄腐殖酸 ,喷施后可促进蛋…     

闽南旱地作物蛴螬发生及防治的研究

通过金龟子成虫在黑光灯下和田间的消长调查、蛴螬的田间定期挖查 ,初步摸清了闽南地区危害花生、大豆、甘薯、甘蔗等旱地作物的蛴螬种类有 2 6种 ,主要种类有 9种。明确了其主要蛴螬种类的生活习性与旱地作物互为相关。通过采用不同的药剂与不同方法进行防治试验 ,筛选出经济有效的药剂种类 ,并根据不同作物的生长特性和不同蛴螬种类的危害特点 ,确定了经济有效的防治适期 ,并制定了相应的防治技术措施     

增铵营养对小麦氮及矿质营养含量和积累的影响

1　引　　言增铵营养 (ＥＡＮ)即混合形态Ｎ营养 ,是相对于单一ＮＯ-3 营养而提出的旱地作物Ｎ营养的新方法 .旱地作物在ＮＯ-3 营养下生长优于ＮＨ+ 4 营养[6] ,但在增铵营养下小麦等旱地作物的干物质积累和产量显著高于两种单一形态Ｎ营养[1～ 3 ,5,7] .同时 ,我们的研究表明 ,增铵营养对小麦生长的促进效应具有明显的基因型差异[3 ] ,但其生理基础尚不明确 .由于植株对两种形态Ｎ的吸收和积累也影响对其它无机离子的吸收 ,因此 ,在增铵营养下 ,不同小麦基因型对Ｎ及Ｐ、Ｋ、Ｃａ、Ｍｇ等营养元素的吸收和积累也会存在差异 ,可能影响小麦…     

《旱地作物氮素营养生理生态》出版发行

由中国科学院水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室上官周平研究员和李世清教授编著的《旱地作物氮素营养生理生态》专著已由科学出版社出版发行。     

《旱地作物氮素营养生理生态》出版

由中国科学院水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室上官周平研究员和李世清教授编著的《旱地作物氮素营养生理生态》专著已由科学出版社出版发行。     

《旱地作物氮素营养生理生态》出版发行

由中国科学院水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室上官周平研究员和李世清教授编著的《旱地作物氮素营养生理生态》专著已由科学出版社出版发行。     

《旱地作物氮素营养生理生态》出版发行

由中国科学院水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室上官周平研究员和李世清教授编著的《旱地作物氮素营养生理生态》专著已由科学出版社出版发行。     

《旱地作物氮素营养生理生态》出版发行

由中国科学院水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室上官周平研究员和李世清教授编著的《旱地作物氮素营养生理生态》专著已由科学出版社出版发行。     

Leaf gas exchange of upland and lowland rice cultivars

Leaf gas exchange of upland and lowland rice cultivars were measured during late vegetative and during grain filling stages in the field under upland and lowland growth conditions. The rate of photosynthesis and water use efficiency (the rate of photosynthesis/the rate of transpiration) under upland conditions decreased with ageing, but generally varied little among four cultivars. At mid-grain filling under lowland conditions, upland cultivars showed lower rates of photosynthesis and transpiration than the lowland cultivars with concomitant reduction in whole plant conductance. At this stage, water use efficiency was higher under upland conditions than under lowland conditions, particularly in the upland cultivars. Water stress reduced the rate of photosynthesis without altering water use efficiency.     

Genomic landscape of parallel domestication of upland rice and its implications

Parallel domestication has been widely acknowledged but itsgenetic basis remains largely unclear. As an important rice ecotype, upland rice was assumedly domesticated multiple times in two rice subspecies (Indica and Japonica) and provides a feasible system to explore the genetic basis of parallel domestication. To uncover the genome‐wide pattern of genetic differentiation between upland and lowland rice and explore the parallelism of genetic changes during upland rice domestication, we obtained whole‐genome sequences of 95 rice landraces and yielded genome‐wide expression data for five tissues of representative accessions of upland and lowland rice. Our phylogenetic analyses confirmed multiple domestications of the upland ecotype in two rice subspecies. Genomic scans based on resequencing data identified substantial differentiation between the upland and lowland ecotypes with 11.4% and 14.8% of the genome diverged between the two ecotypes in Indica and Japonica, respectively. Further genome‐wide gene expression analyses found that 30% of effectively expressed genes were significantly differentiated between two ecotypes, indicating the importance of regulation changes in the domestication of upland rice. Importantly, we found that only 1.8% of differentiated genomes and 1.6% of differentially expressed genes were shared by upland Indica and upland Japonica, suggestive of largely unparallel genetic alterations during upland rice domestication. These findings not only provide new insights into the genetic basis of parallel domestication at the genome scale but could also facilitate geneticimprovement and breeding of rice and crops in general.     

Connectivity in coastal systems: Barrier island vegetation influences upland migration in a changing climate

Due to their position at the land–sea interface, barrier islands are vulnerable to both oceanic and atmospheric climate change‐related drivers. In response to relative sea‐level rise, barrier islands tend to migrate landward via overwash processes which deposit sediment onto the backbarrier marsh, thus maintaining elevation above sea level. In this paper, we assess the importance of interior upland vegetation and sediment transport (from upland to marsh) on the movement of the marsh–upland boundary in a transgressive barrier system along the mid‐Atlantic Coast. We hypothesize that recent woody expansion is altering the rate of marsh to upland conversion. Using Landsat imagery over a 32 year time period (1984–2016), we quantify transitions between land cover (bare, grassland, woody vegetation, and marsh) and the marsh–upland boundary. We find that the Virginia Barrier Islands have both gains and losses in backbarrier marsh and upland, with 19% net loss from the system during the timeframe of the study and increased variance in marsh to upland conversion. This is consistent with recent work indicating a shift toward increasing rates of landward barrier island migration. Despite a net loss of upland area, macroclimatic winter warming resulted in 41% increase in woody vegetation in protected, low‐elevation areas, introducing new ecological scenarios that increase resistance to sediment movement from upland to marsh. Our analysis demonstrates how the interplay between elevation and interior island vegetative cover influences landward migration of the boundary between upland and marsh (a previously underappreciated indicator that an island is migrating), and thus, the importance of including ecological processes in the island interior into coastal modeling of barrier island migration and sediment movement across the barrier landscape.     

Upland Forest Linkages to Seasonal Wetlands: Litter Flux, Processing, and Food Quality

The flux of materials across ecosystem boundaries has significant effects on recipient systems. Because of edge effects, seasonal wetlands in upland forest are good systems to explore these linkages. The purpose of this study was to examine flux of coarse particulate organic matter as litter fall into seasonal wetlands in Minnesota, and the relationship of this flux to development of mosquitoes (Aedes aegypti). We hypothesized that litter flux into seasonal wetlands was dominated by upland plant litter that was lower quality and slower to breakdown than wetland litter, and that development rate of mosquitoes reared on upland litter was less than those reared on wetland litter. Of total litter fall into the wetlands, 71% originated in upland forest. Carbon to nitrogen ratios differed between upland litter (mostly sugar maple (Acer saccharum) and trembling aspen (Populus tremuloides) leaves) and wetland litter (mostly black ash (Fraxinus nirgra) leaves), averaging 63.9 and 47.7, respectively over two years. Breakdown rate of black ash leaves was faster than upland leaves (k (day⁻¹) = 0.00329 and 0.00156, respectively), based on the average between wetland margins and centers. Development of mosquito larvae fed black ash leaves was faster than larvae fed upland leaves. Our results demonstrate linkages between upland forests and seasonal wetlands through litter fall. The abundance of upland litter in the wetlands may influence litter breakdown and carbon assimilation by invertebrates. Wetlands receiving high amounts of upland versus wetland litter may be lower quality habitats for invertebrates that depend on detrital pools for their development.     

Metabolic adaptation to flooding stress in upland and lowland rice seedlings

Ability of metabolic adaptation in upland and lowland rice (Oryza sativa L.) seedlings to flooding stress was compared. Flooding stress increased alcohol dehydrogenase (ADH) activity and ethanol concentration in shoots and roots of the upland and lowland rice seedlings. The difference in ADH activity and ethanol concentration in shoots between the upland and lowland rice was not apparent. However, both ADH activity and ethanol concentration in roots of the lowland rice were 2-fold greater than those in roots of the upland rice, suggesting that flooding-induction of ethanolic fermentation in lowland rice roots may be significantly greater than that in the upland rice roots. Since flooding often causes the anaerobic conditions in rooting zone than aerial part of plants and ethanolic fermentation is essential to survive in the anaerobic conditions, the ability of metabolic adaptation in lowland rice seedlings to flooding stress may be greater than that in upland rice seedlings.     

海岛棉与陆地棉叶绿素含量变化的差异研究

以5份陆地棉和4份海岛棉为材料,研究了整个发育进程中陆地棉和海岛棉叶绿素的变化规律之间的差异,结果显示：陆地棉与海岛棉的叶绿素a、叶绿素b和叶绿素a＋b各有不同动态变化规律,其叶绿素a/b在整个发育进程中的变化也有差异。海岛棉与陆地棉的叶绿素a变化趋势有较大差别,陆地棉的叶绿素a含量在6月18日（苗期）最高,峰值出现在8月6日,海岛棉峰值、最大值均在7月4日（现蕾期）;叶绿素b含量表现为陆地棉、海岛棉峰值均在8月6日（花铃期）,但海岛棉平均值高于陆地棉;陆地棉的叶绿素a＋b和叶绿素a曲线相似,海岛棉的叶绿素a＋b和叶绿素b曲线相似;陆地棉叶绿素a/b值表现苗期最大,然后迅速下降,海岛棉a/b值表现普遍低于陆地棉,其变化趋势为前期在7月4日出现峰值,然后下降再升高。实验说明陆地棉和海岛棉叶绿素的合成机制、调控机理可能不同。     

陆地棉EST-SSRs在向日葵中的通用性研究

利用陆地棉EST-SSR s(Expressed sequence tags-s im p le sequence repeats)在陆地棉和向日葵品种中进行了通用性分析。利用本实验室合成的1 500对陆地棉EST-SSR s在4个陆地棉品种中进行了扩增,有效扩增比率为95%,扩增产物符合预期大小(50~500 bp);每对引物可以检测到1~6个数目不等的片段(a lle le),平均约为2.7个;每2个陆地棉之间大约有7%~9%的多态性。从1 500对陆地棉EST-SSR s引物中选取400对引物在向日葵中进行了扩增,有效扩增比率为63%,每对引物可以检测到1~6个数目不等的片段,平均为1.7个,片段大小介于50~500 bp之间。选取了200对在向日葵中得到有效扩增的引物对向日葵G 101的父母本进行了多态性筛选,约25%引物具有多态性。结果表明,陆地棉EST-SSR s在向日葵中具有较高的通用性,可用于向日葵比较基因组研究和分子标记研究。     

云南澜沧县陆稻品种资源多样性和原生境保护

云南澜沧县不仅存在丰富的陆稻品种多样性和形态多样性,而且也存在陆稻生长环境和栽种管理方法的多样性,即山地民族在陆稻栽种方面的土著知识（indigenous knowledge,IK）多样性,讨论了由传统的刀耕火种生产制度过渡到现代固耕生产方式对陆稻生产及品种资源保存和保护的影响。提出了陆稻资源多样性保护的建议。     

大鵟的食性改变:来自稳定性碳同位素的证据

通过对大规模灭鼠后的海北高寒草甸生态系统大鵟、小型哺乳类以及雀形目鸟类肌肉稳定性碳同位素比值的测定发现,大篱的肌肉稳定性碳同位素比值介于-22．60‰和-23．10‰之间;小型哺乳类和主要雀形目鸟类肌肉稳定性碳同位素比值分别介于-25．57‰和-25．78‰以及-24．81‰和-22．51‰之间,且它们之间差异性显著。基于碳同位素的分馏模式(即动物和它食物之间稳定性碳同位素分馏在1‰～2‰之间),我们推断经大规模灭鼠后,大篱的食性发生了较大变化,其食物主要来源于高寒草甸的雀形目鸟类,而非原来的小型哺乳类。通过稳定性同位素营养级模型的运算发现,大蔫处在4．23左右的营养级;雀形目鸟类处在2．4到3．39左右的营养级,而小型哺乳类则处在1．45到1．82左右的营养级。进而采用稳定性同位素质量平衡模型计算得出,大篱的食物由35．04％的小型哺乳类和64．96％的雀形目鸟类所组成,进一步说明小型哺乳类在大量灭鼠后仅占大篱食物的很小一部分。由此可见,采取大规模的化学灭鼠,不仅降低了小型啮齿类天敌——大鵟的数量,而日使得其食谱发毕了巨大改变而转向草甸主要雀形目鸟类[动物学报49(6)：764～768,2003]。     

西双版纳社区旱稻品种多样性与就地保护初探

应用户级水平农业生物多样性评价方法,对云南省西双版纳州3个少数民族村寨(哈尼族大卡老寨、基诺族巴卡小寨和傣族曼那龙寨)的旱稻(Oryza sativa)品种进行收集,就旱稻品种的管理和利用等问题进行了问卷调查和农户访谈,并基于农艺性状的统计分析,初步探讨了社区旱稻品种多样性的就地保护措施。结果如下：(1)在3个调查村寨共记载收集到31个旱稻品种,多样的旱稻品种满足了人们的不同需求;(2)主成分分析结果表明,旱稻品种农艺性状多样性主要表现在产量性状和剑叶形态两个方面,其中巴卡小寨和大卡老寨的品种多样性均高于曼那龙寨,并且这些早稻品种中存在具优良性状的稻种资源;(3)3个少数民族村寨具有不同的民族文化背景,不同民族间或不同村寨农户间自发的种子交换以及他们传统的轮作、间作耕作方式,维持和提高了旱稻品种多样性;(4)通过保护民族文化和传统习俗,充分利用当地民族的旱稻种植管理知识,促进民间自发的种子交换,由政府、科研机构和农户共同参与,通过示范和培训加强科学指导,是对西双版纳社区旱稻品种资源多样性进行就地保护的有效措施。