延安市蔬菜生产现状、发展思路及对策

1　生产现状延安市位于陕北南部,属黄河中游地区。地处东经107°40′～110°33′、北纬35°40′～37°30′。辖13个县(区),167个乡镇,3376个行政村,全市总土地面积367.12万hm2,可耕地面积97.13万hm2。现有人口205.61万人,其中农业人口155万人。平均海拔1200m,年日照时数逾2600h     

优质大豆寒地高产栽培技术

黑龙江省五大连池市位于东经125°45′～127°30′,北纬48°15′～49°10′。无霜期90～115天,属高纬寒地。全市总耕地面积7.8万hm2,其中大豆6.33万hm2,占总耕地面积的81.2%。为了提高大豆的质量和产量,我     

会泽马铃薯引领绿色农业强县建设

会泽县位于云南省东北部乌蒙山主峰南麓,地处东经103°03′～103°55′、北纬25°48′～27°04′之间。全县详查耕地面积14.3万hm2,大部分耕地位于海拔2300ml以上低纬度高海拔     

庆元县无公害茶树高产优质栽培技术

庆元县位于东经118°50′～119°30′,北纬27°25′～27°51′,属中亚热带过渡的季风性湿润气候区,具有四季分明,年温适中,雨量充沛,光热充足等特点。是瓯江、闽江、福安江的发源地,故有"三江之源"美称。全县土地面积18.87万hm2(其中耕地面积1万hm2),人均土地1 hm2,垂直分布在海拔240～1857m,境内地面起伏强烈,群山怀抱,峰峦叠嶂,是个山清水秀"九山半水半分田"的山区县。近年来庆元县政府立足"中国生态环境第一     

达里湖浮游植物调查

达里湖(达里诺日)位于内蒙古自治区赤峰市克什克腾旗境内,东经116°26′～45′,北纬43°13′～23′,海拔1226～1228m。是一个碳酸盐型半咸水湖泊。面积约238km2(35.7万亩)。平均水深6.7m,最大水深13.0m。湖水的主要来源是:贡格尔河、沙里河、亮子河、耗来河4条河流,此外,还有地下水补给。在达里湖的东南部有岗更诺尔(牤牛泡子),面积0.21万hm2,由沙里河与达里湖沟通;西北部有鲤鱼泡子,面积0.02万hm2,经耗来河与达里湖     

景东县农业环境保护现状与对策

1景东县基本情况及农业环境保护现状1.1景东县基本情况景东彝族自治县位于滇西南中部,普洱市北端,东经100°24′～101°15′、北纬23°57′～24°50′,境内最高海拔3 370 m,最低海拔795 m,属南亚热带季风气候。国土面积4 466 km2,其中山区面积4 265km2,占95.5%,坝区面积201 km2,占4.5%。2009年末辖4镇9乡,3个社区,166个村民委员会,2 339个村民小组,农业人口333 464人。常用耕地面积3万hm2,其中水田9 229.5 hm2,旱地20 770.5     

临泽县小屯灌区五眼干渠透水衬砌设计与施工

临泽县地处河西走廊中部,位于东经99°51′～100°30′、北纬38°57′～39°42′之间,小屯灌区位于临泽县城以北,距临泽县城9km,全灌区总灌溉面积0.57万hm2,其中农田灌溉面积0.31万hm2,林草地灌溉面积0.26万hm2,属引泉灌溉的灌区,地下水丰富,且具有较厚淤泥质土以及腐殖质土,     

平塘玉米高产的影响因素与对策

平塘县地处贵州南缘中部,与广西南丹毗邻,位于北纬25°29′～26°06′、东经106°40′～107°26′;年均温17℃,年总积温6203℃,降雨量1295mm,无霜期312d;最高海拔1487.7m,最低海拔465m,属亚热带季风湿润气候区;全县耕地面积5.12万hm2,总人口29.1万,是典型的喀斯特地貌山区农业县.     

应用西门塔尔牛冻精改良土种黄牛的效果

乌鲁木齐位于准噶尔盆地南缘,地处东经86°37′56″～88°18′22″,北纬43°01′88″～44°06′11″,总面积1 300 km2,耕地约6万hm2,草场面积64.2万hm2,农副产品丰富,很适应发展以牛羊为主的草食家畜.     

南召县木本叶用植物资源开发利用调查

南召位于河南省西南部,伏牛山南麓,南阳盆地北缘,鸭河口水库上游。地理坐标为北纬33°12′~33°43′,东径111°55′~112°54′,总面积29.46万hm2,其中林业用地面积19.07万hm2,活立木蓄积300余万m3,森林覆盖率60.1%,是个以林为主、经济欠发达的山区县。南召三面环山、一面临水,呈"簸箕"形,海拔从143m到2153.1m,以中低山和丘陵为主,兼有平原。南召     

穴盘规格和苗龄对塑料大棚菜豆性状及产量的影响

本试验以菜豆品种先行者为试材,采用32孔、50孔两种规格穴盘,设置10、15、20、25 d等4个苗龄段,通过研究不同穴盘规格和苗龄对菜豆性状及产量的影响,筛选出适合菜豆育苗的穴盘规格和适宜的苗龄。结果表明：穴盘育苗的营养面积增大,菜豆产量随之增加,25 d苗龄条件下,32孔穴盘的前期产量和总产量均显著高于50孔穴盘;随着苗龄的增长,菜豆的前期产量和总产量呈增加趋势,其中25 d苗龄的产量显著高于其他苗龄。综合上述各项指标,菜豆育苗阶段,10 d苗龄可选用32孔、50孔穴盘,15 d以上秧苗选用32孔穴盘为宜。     

不同基因型小麦苗期耐低氮性评价及筛选

氮素作为重要的营养元素,限制着小麦的生长发育和经济产量,筛选和培育耐低氮小麦品种是提高氮素利用率、降低生产成本的有效途径。以118份不同基因型小麦为材料,在低氮(0.1 mmol·L^-1)和正常氮(5 mmol·L^-1)条件下苗期水培,测定根干重、茎叶干重、根冠比、植株干重、最大根长、初生根数和二级初生根数等相关指标,采用模糊隶属函数法、主成分分析以及聚类分析法综合评价小麦品种的耐低氮性。结果表明,在低氮胁迫下小麦幼苗的根干重、根冠比和初生根数目显著提高,茎叶干重、植株干重和最大根长不同程度的降低,7个苗期性状指标在两个氮水平下均存在显著性差异。主成分分析提取3个主成分,贡献率分别为 43.575%、22.904%和17.873%,累积贡献率达 84.351%。以耐低氮性综合评价D值进行聚类分析,将118份小麦品种划分为强耐低氮型、耐低氮型、中间型、较敏感型和敏感型5类。筛选出3份耐低氮型小麦（齐大195、金丰7183和天民198）和2份强耐低氮型小麦（山农0917和鲁麦8号）。不同小麦品种的耐低氮机制不同,研究结果为小麦耐低氮品种的选育提供理论依据和材料基础。     

Segregation of form, color, movement, and depth: anatomy, physiology, and perception

Anatomical and physiological observations in monkeys indicate that the primate visual system consists of several separate and independent subdivisions that analyze different aspects of the same retinal image: cells in cortical visual areas 1 and 2 and higher visual areas are segregated into three interdigitating subdivisions that differ in their selectivity for color, stereopsis, movement, and orientation. The pathways selective for form and color seem to be derived mainly from the parvocellular geniculate subdivisions, the depth- and movement-selective components from the magnocellular. At lower levels, in the retina and in the geniculate, cells in these two subdivisions differ in their color selectivity, contrast sensitivity, temporal properties, and spatial resolution. These major differences in the properties of cells at lower levels in each of the subdivisions led to the prediction that different visual functions, such as color, depth, movement, and form perception, should exhibit corresponding differences. Human perceptual experiments are remarkably consistent with these predictions. Moreover, perceptual experiments can be designed to ask which subdivisions of the system are responsible for particular visual abilities, such as figure/ground discrimination or perception of depth from perspective or relative movement--functions that might be difficult to deduce from single-cell response properties.     

ICP-OES法同时测定果蔬中铅、砷、镉、铬、铜、锡含量

果蔬样品经混酸消化后,控制一定的酸度,定容后应用等离子体发射光谱法(ICP-OES)对果蔬中铅、砷、镉、铬、铜、锡六种有害重金属进行测定,研究了分析测定条件,方法简单快速。测定结果表明,五种元素的加标平均回收率在91.0%~107%之间。其RSD均小于3.5%。按该方法进行处理及测定铅、砷、镉、铬、铜、锡,在选择的测定条件下最低检出限分别为0.0006 mg/kg、0.0003 mg/kg、0.00003 mg/kg、0.00005 mg/kg、0.00003 mg/kg、0.0006 mg/kg。     

一串红N、P、K、Ca、Mg、Fe缺素症状研究

以‘展望红’为材料,研究N、P、K、Ca、Mg、Fe缺乏对其生长发育的影响,并总结缺素症状,研究结果表明:N缺乏时植株矮小,叶发黄;P缺乏时叶色暗绿,且影响开花;K缺乏时基部叶枯黄,并易落叶;缺Fe症状较为明显,但能正常开花;Ca、Mg未表现出缺素症状,且各项指标要优于全素处理;N、P显著影响一串红的生长发育,K对开花品质的影响较大。     

Fiber, food, fuel, and fungal symbionts

Virtually all plants of economic importance form mycorrhizae. These absorbing organs of higher plants result from a symbiotic union of beneficial soil fungi and feeder roots. In forestry, the manipulation of fungal symbionts ecologically adapted to the planting site can increase survival and growth of forest trees, particularly on adverse sites. Vesicular-arbuscular mycorrhizae, which occur not only on many trees but also on most cultivated crops, are undoubtedly more important to world food crops. Imperatives for mycorrhizal research in forestry and agriculture are (i) the development of mass inoculum of mycorrhizal fungi, (ii) the interdisciplinary coordination with soil management, plant breeding, cultivation practices, and pest control to ensure maximum survival and development of fungal symbionts in the soil, and (iii) the institution of nursery and field tests to determine the circumstances in which mycorrhizae benefit plant growth in forestry and agri-ecosystems.