渗灌和地膜覆盖对冬小麦产量及绿色面积构成的影响     

裴艳婷  李娜娜  李慧  王树亮  谢连杰  田奇卓 《中国农学通报》2009,25(4):115-118

为寻求小麦节水栽培的有效调控技术和相应效果,研究了灌水方式与地膜覆盖的不同结合,对冬小麦产量及其构成、穗茎叶等器官绿色面积的影响。结果表明：渗灌和覆膜均可不同程度提高产量,但两个因素相组合效果更显著;20cm和40cm渗灌覆膜在总耗水量在459mm的控制条件下,分别比对照增产20.34%和20.16%;而在有深层水补给的露天条件下,分别增产11.11%和13.67%。不同处理对穗、茎和叶器官的面积及其比例,也产生显著影响;在不同栽培条件下,开花期非叶光合器官占总绿色面积的比例在61.33%~62.69%之间。  相似文献   

Log Characteristics and Sawn Timber Recovery of Home-Garden Teak from Wet and Dry Localities of Kerala, India   总被引：1，自引：1，他引：0  

Puthenpurayil Kumaran Thulasidas  Kanthila Mahabala Bhat 《Small-Scale Forestry》2009,8(1):15-24

There is a widely held view among smallholders that teak timber produced from small-scale agroforestry systems, especially home-garden forestry, fetches a lower price than that from conventional plantation forestry. To examine the veracity of this view, the wood quality attributes of teak from two home gardens in the district of Ernakulam (wet site) and Palakkad (dry site) in India were compared to those of forest plantation in Nilambur. The logs were graded using standard timber trade practices into high, medium and low quality as determined by the potential sawn timber grade-yield recovery pattern. Of 96 home garden teak logs (aged 35 years) from wet and dry sites, 59% belonged to timber Grade II–IV and the rest were classified as poles. Grade I logs (export quality) with a girth above 150 cm were not available from either of the homesteads. Faster-grown teak in the wet site produced large diameter logs (dbh 1.37 m) with average diameter of 39.6 cm, which is comparable to that of best site quality in India. In contrast, the average dbh for teak grown in the dry site was 24 cm as compared to the average dbh of 31 cm recorded from the same aged forest plantation in Nilambur. It was found that only 10% of logs belonged to Grade II timber and the rest fell under grades III and IV with more frequent visual defects. The sawn timber recovery percentage was lower for the dry site (66.8%), whereas there was no significant difference in grade from the wet and forest plantation sites, with recovery rates of 76.5% and 78.8%, respectively. The general notion that home garden teak has a large proportion of sapwood seems to be baseless, no significant difference being found between the heartwood-sapwood ratio of home-garden and forest plantation teak. Lack of appropriate silvicultural practices in home-garden forestry caused the production of more defective logs, adversely affecting the market price of timber.

Puthenpurayil Kumaran ThulasidasEmail:

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Atmospheric Environmental Impact Simulation of Gas Fired Boilers as Peak Load Heat Sources     

WANG Hai chao  JIAO Wen ling  ZOU Ping hua 《保鲜与加工》2009,(2):131-137

Heating with gas can reduce air pollutant emission and therefore becomes a new sort of peak load heat source. To study the atmospheric environmental impact, we adopted a newly built combined heating system and simulated its pollutant dispersion for centralized and distributed peak heating. The simulations were based on the improved regulatory environmental impact assessment (EIA) guidelines for atmospheric environment. The model developed an algorithm for infill wind direction simulation and exported pollutant contours for comparisons. Simulation results show that the system's atmospheric environmental impact is related not only to the pollution emission quantity per quantificational heating, but also to the distribution of heat resource in the gas fired boilers. The centralized peak heating has comparatively small environmental impact; for distributed peak heating, the more concentration of gas fired boilers distribution is applied, the more serious environmental impact will be. In addition, the optimum setting proportion of gas fired boilers should be between 0.2 and 0.6 from the perspective of environmental impact.  相似文献   

白桦容器育苗的适宜基质筛选   总被引：8，自引：0，他引：8  

贾斌英  徐惠德  刘桂丰  李开隆  孙志虎  彭红梅  滕文华 《东北林业大学学报》2009,37(11)

为了给东北地区白桦(Betula platyphylla Suk.)容器育苗提供适宜的基质配方,在东北林业大学白桦强化育种基地温室内,以河沙、草炭和耕作土为基质,对其18种配比的育苗结果进行了筛选.结果表明:3种基质的不同配比能够显著影响白桦苗木的SPAD值、苗高、地径和全株生物量.当河沙体积分数在0～20%的范围内,白桦苗木的SPAD值、苗高、地径和全株生物量处于最高值,随着基质中河沙比例的进一步增加,各指标呈抛物线下降;随着草炭比例的增加,各指标则呈现上升趋势;耕作土比例的变化,各指标基本不变.综合基质不同配比下白桦幼苗的SPAD值、地径、苗高和全株生物量结果,18种育苗基质可分为3组:第1组为S6、S9 、S11、S16处理,第2组为S3、S7、S10、和S15处理,第3组为S1、S2、S4、S5、S8、S12、S13、S14、S17和S18处理.遵循育苗基质的适用性和经济性原则,白桦容器育苗的适宜基质配比为S6处理,即V(草炭): V(沙子): V(耕作土)=2: 1: 7.  相似文献   

猪血豆腐制作工艺的研究     

苏宇静  李瑜 《安徽农业科学》2011,39(30):18760-18761,18770

[目的]研究食品添加剂对猪血豆腐质量的影响。[方法]把不同比例的食品添加物加入到猪血中,通过评定一系列血豆腐质量指标,以研究不同含量添加物对血豆腐质量的影响,并确定最佳的添加比例,用于改进血豆腐工艺质量。[结果]随着食盐含量的增加,豆腐的凝固及成品质量都明显提高;随着CMC-Na、瓜尔胶含量的增加,豆腐的质量水平逐渐提高,但口味由好逐渐变差;随着血与水比例的提高,豆腐凝固品质逐渐变好,但成型变差;当添加3%食盐、0.25%CMC-Na、0.20%瓜尔胶、血∶水为1∶2.4时,经过凝固,切块,蒸煮,冷却的血豆腐成品有较好的综合品质。[结论]适当含量食品添加物的加入以及合理的原料配比,可有效提高猪血的利用率及血豆腐的品质、产量。  相似文献   

表面活性剂对农药雾滴在甘蓝菜叶面上扩展面积和蒸发时间的影响研究   总被引：2，自引：0，他引：2  

左雯  饶志坚  吴国星  陈秀红  余杨 《西南大学学报(自然科学版)》2011,33(9)

农药雾滴在作物叶面上的扩展面积和蒸发时间是影响农药施药效率的两个重要因素.选用不同种类及不同添加比例的表面活性剂对甘蓝菜叶子进行试验,采用连续拍摄雾滴扩展和蒸发全过程的方法,记录农药雾滴在甘蓝菜叶面上的扩展面积和蒸发时间的数据.试验证明,在农药药液中添加不同种类和不同比例的表面活性剂,会对农药雾滴在甘蓝菜叶面上的蒸发过程产生不同程度影响.要进一步地开展研究工作,针对特定叶面,筛选出最佳效果的表面活性剂,并寻找表面活性剂的最佳添加比例,为提高农药的施药效率提供依据.  相似文献   

应用SSR分子标记评价不同年代东北三省粳稻基因组遗传构成     

刘迪  李红宇  孙健  徐正进 《黑龙江农业科学》2011,(7):1-6

为进一步明确北方粳型水稻基因组遗传构成,利用52个SSR分子标记对79份不同时期东北粳稻品种进行遗传多样性与基因组遗传构成的研究.结果表明:品种遗传多样性在省份间呈现出辽宁＞黑龙江＞吉林,在年代间呈现出2001～2008＞1981～1990＞1991～2000＞1963～1980的趋势;基因组籼稻成分比例表现为辽宁品种...  相似文献   

不同溶剂及配比对轮虫脂肪提取的影响     

裴怀全  董晓庆  朱成成  刘洪健  董婧  陈玉珂  张东鸣 《中国水产科学》2012,19(6):1074-1078

研究了提取溶剂、次数以及溶剂的配比对轮虫脂肪提取的影响。分别用氯仿甲醇体积比为2:1、1:1、1:2,苯石油醚体积比2:1、1:1、1:2,丙酮石油醚1:4、3:7、2:3作为提取溶剂,提取冻干轮虫(Brachionus rotundiformis)样品脂肪,测定脂肪含量与皂化值,筛选得出3种提取溶剂的最佳配比;比较提取次数为1～3次间脂肪含量的差异,得出最佳提取次数;将3种最佳配比与索氏提取法(国标)提取样品脂肪进行比较,测定脂肪含量与皂化值。结果显示,在冻干轮虫脂肪提取中,提取次数对样品脂肪含量没产生显著影响(P>0.05);3种溶剂的最佳配比分别为氯仿甲醇2:1、苯石油醚1:2、丙酮石油醚2:3;其中丙酮石油醚2:3处理组的脂肪含量和皂化值分别达到9.71%和198,均显著高于索氏提取法(国标)和其余处理组(P<0.05)。故轮虫脂肪提取1次为宜,最佳溶剂及配比为丙酮石油醚体积比2:3,本方法具有提取高、时间短、安全性高、成本低等优点,具有一定的实际应用价值。  相似文献   

基追肥比例对烤烟产质量及烟叶香气的影响     

胡喆文  杨悦章  李佛琳  杨焕文  胡小曼  方志存  范业晨  陈茂建  李成杰 《云南农业大学学报(自然科学版)》2011,26(Z1):58-62

 为了寻求最适合的肥料基追比例对烟叶产质量及其与烟叶香气的关系,进行了基追肥比例8∶2,7∶3,6∶4,5∶5,3∶7和全追肥共6个处理,对烤烟烟叶产质量及烟叶香气的影响试验。结果表明：基追比3∶7（T5）的株高、茎围、叶长最大,分别达到了97.00,9.37,66.90cm。T5产量、均价、上中等烟比例最高,分别达到了3687.98kg/hm2,13.48元/kg,86.54%。基追比8∶2（T1）致香物质含量最高,为474.36μg/g,其次是7∶3（T2）,为469.43μg/g,5∶5（T4）致香物质含量最低,为383.38μg/g。  相似文献   

The Rht13 dwarfing gene reduces peduncle length and plant height to increase grain number and yield of wheat     

G.J. Rebetzke  M.H. Ellis  D.G. Bonnett  A.G. CondonD. Falk  R.A. Richards 《Field Crops Research》2011,124(3):323-331

The green-revolution Rht-B1b and Rht-D1b dwarfing alleles are usually associated with increased wheat yields but are linked to reduced early growth and poor emergence if sowing conditions are unfavourable. Other dwarfing genes are available but not used in commercial breeding. The Rht13 bread wheat donor, Magnif M1, produces uniquely short peduncle and penultimate internodes to reduce plant height. A set of near-isogenic (NILs) and recombinant inbred (RILs) lines varying for height were developed from the cross of Magnif M1 and the Rht8c-containing Chuan-mai 18, and evaluated for a range of agronomic characteristics across favourable environments. Reductions in plant height were associated with increased grain number (r² = 0.35**) and harvest index (r² = 0.62**) in the NILs. Reduced-height RILs containing the Rht13-linked, Xgwm577_M microsatellite marker were significantly shorter, produced greater biomass, yield and harvest index, and increased spike and grain number than lines without the marker. Approximately 74 and 7% of the total phenotypic variance in plant height was accounted for by allelic differences in Xgwm577 and Rht8 loci, respectively. The peduncle and penultimate peduncle internodes of Rht13-containing lines were proportionately shorter than Rht8c-containing sibs and lines containing the Rht-B1b dwarfing allele. The unique height-reducing phenotype, increased grain number and yield associated with Rht13 indicate considerable potential for use of this dwarfing allele for improving wheat performance.  相似文献