Molecular prevalence,risk factors assessment and haemato-biochemical alterations in hepatozoonosis in dogs from Punjab,India     

《Comparative immunology, microbiology and infectious diseases》2017

Hepatozoonosis caused by Hepatozoon canis is an important tick-borne disease of dogs in tropical and sub-tropical regions throughout the world. In the present study evaluation of blood samples collected from 225 dogs presented at Small Animal Clinics, GADVASU, Ludhiana, Punjab (India) was done for the presence of H. canis by PCR based assay targeting a portion of 18S rRNA gene. Of the total samples subjected to PCR, an amplicon of 666 bp was detected in 13.78% samples whereas, routine blood smear examination revealed gamonts in 5.78% samples. Furthermore, prevalence of H. canis infection was found to be significantly associated with season, being highest in summer and lowest in winter while other risk factors e.g. age, sex and breed showed non-significant association. In terms of various clinico-pathological parameters, significant drop in haemoglobin, total red blood cell count, packed cell volume and lymphocytes were recorded in positive cases whereas the total white blood cell count was non-significantly increased. The haematological alterations in the positive cases were lymphopenia, anaemia, thrombocytopenia, relative neutrophilia, neutrophilic leucocytosis, eosinophilia, monocytosis and lymphocytosis while the biochemical profile revealed hypoproteinemia and increased levels of blood urea nitrogen and creatinine (in positive cases) pointing towards renal failure.  相似文献   

不同燕麦基因型源库关系对穗粒数形成过程的影响     

柳妍娣  赵宝平  米俊珍  武俊英  刘景辉 《麦类作物学报》2023,(12):1558-1569

为了解燕麦穗粒数形成过程与源、库特征之间的关系，连续两年以10个不同来源、熟期、穗型、株型、小穗数的燕麦品种为试验材料，测定三叶期至拔节期的幼穗分化阶段及抽穗期源库特征，采用方差分析、聚类分析、逐步回归分析等方法，分析不同燕麦基因型源库特征及对穗粒数形成过程的影响。结果表明，燕麦穗粒数形成过程存在基因型差异，幼穗分化较好品种的穗粒数较全部品种平均值高11.22%~65.43%；幼穗分化较好品种的光合势、干物质量、粒数叶比、收获指数显著高于幼穗分化较差品种，其中粒数叶比和收获指数是影响穗粒数形成的主要因素，粒数叶比和收获指数较全部品种平均值分别高0.99%~68.74%和0.85%~13.80%。综上所述，源库协调是燕麦幼穗分化良好的生理基础，可通过提高光合势和干物质量达到增源的目的，进而提高穗粒数。  相似文献   

增加光照及其与改变源库互作对大豆产量构成因素的影响   总被引：8，自引：2，他引：6  

刘晓冰  S. J. Herbert  金剑  张秋英  李艳华  王光华 《大豆科学》2006,25(1):6-10

生殖生长期间的光照强度是决定大豆产量的关键环境因素.在美国麻省和中国黑龙江两地,通过在不同时期,对不同密度的大豆群体进行增加光照和改变源库处理,研究了两地产量及产量构成因素对增加光照光变化的反应.结果表明,不同时期增加光照光处理的增产效果不同,开花初期和结荚初期增加光照最为明显,花期增加光照增加单株荚粒数,而结荚初期增加光照增加百粒重.鼓粒期增加光照处理,百粒重不同品种在不同密度条件下增产不显著,说明鼓粒期后的光照条件对大豆产量及百粒重的调节有限.在不同的光照条件下,源库在产量形成中的作用不同.在自然光照条件下,剪叶处理产量下降幅度较去荚大,即源在产量形成中更加重要些,而在花期的增加光照处理条件下,库也成为影响产量的重要因子,可见,光照条件在源库关系中起着显著的协调作用.  相似文献   

甜菜源库关系的研究   总被引：5，自引：1，他引：5  

周海燕  张少英  李国龙  张海霞 《华北农学报》2008,23(3)

为阐明源、库的关系对甜菜产量形成的影响。运用比较生理学的方法,研究了不同特性甜菜品种群体源、库的形成及其相互关系以及源、库发展在产量形成中的作用。结果表明,甜菜群体LAI和LAD可作为衡量源大小及能力的重要指标。光合源的同化能力直接影响着块根库容的大小,后期较大的光合源会抑制块根库的扩大,影响甜菜产量的形成。揭示了丰产、高糖甜菜品种的源库关系,LAI峰值出现在块根及糖分增长期,最大LAI应在4.3以上,达到峰值后要有20 d左右的相对稳定持续期,糖分积累后期LAI应保持在2.4左右。群体LAD应在块根及糖分增长期达到19.3 m2.d以上,后期呈缓慢下降变化。以上结果可为指导甜菜生产实践提高产量提供理论依据。  相似文献   

晚播小麦源库调节对籽粒灌浆期光合物质分配及产量因素的影响   总被引：17，自引：0，他引：17  

王振林  尹燕枰 《中国农业科学》1996,29(1):50-58

 采用#+（14）C示踪方法对源库调节与晚播小麦籽粒灌浆期光合物质分配的关系进行了研究。晚播小麦在籽粒灌浆期旗叶的光合物质主要用于穗部籽粒生长；倒二叶光合物质亦主要供给籽粒，但向茎秆和根系中的分配增多；倒三叶是标记的三叶中光合物质向根系分配比例最大，向籽粒分配比例最小的叶片。研究表明，源库调节能影响到晚播小麦籽粒灌浆期的光合物质分配。穗库容降低，各叶片光合物质向穗部籽粒分配比例减少，向根系、茎叶中分配增多；叶源量减少，一般则向穗部籽粒分配比例增多。不同类型品种叶片光合物质在植株各器官间的分配受源库调节的影响程度不同。晚播小麦源库调节对穗粒数、粒重及其它穗部性状的影响因不同类型品种而异。相对减少源对鲁215953、鲁麦5号、鲁麦7号和鲁麦14号的穗粒数、粒重影响较小，但使鲁麦15号和辐63的穗粒数和粒重明显降低。  相似文献   

氮肥运筹及密度对中优752源库关系和剑叶温度的影响   总被引：2，自引：0，他引：2  

田智慧  潘晓华 《江西农业学报》2008,20(6):10-13

以三系籼型杂交中稻中优752为材料,研究了氮肥运筹及密度对其源库关系和剑叶温度的影响。研究表明：在适宜施氮量的情况下,适当增加中后期施氮比例和适度稀植都能提高粒叶比和库源增量比、降低生育后期根系活力的衰退值,有利于源库协调。粒叶比和库源增量比与产量均显著正相关,生育后期根系活力的衰退值与产量极显著负相关。增施氮肥、增加中后期的施氮比例及适度稀植能降低剑叶温度。抽穗期及抽穗后25 d剑叶温度与产量呈极显著负相关,而抽穗期剑叶温度与抽穗期的伤流强度极显著负相关。  相似文献   

Microphytic crusts,shrub patches and water harvesting in the Negev Desert: the Shikim system     

Eldridge  David J.  Zaady  Eli  Shachak  Moshe 《Landscape Ecology》2002,17(6):587-597

Human-made contour banks are a central component of theShikim water harvesting system in Israels Negev Desert.Efficient water capture depends on the presence of a stable microphytic crustwhich directs surplus surface runoff into the banks where it is stored. We usedsimulated rainfall to examine the impact of soil surface disturbance on runoffand sediment transport, and the effect of this on the efficiency of resourcecapture within the Shikim system. Two disturbance regimes:1) removal of the microphytic crust only, and 2) removal of the crust and shrubpatches by cultivation, were compared with an undisturbed control. In theundisturbed state, 32% of rainfall was redistributed as runoff. This runoffpenetrated approximately 27% deeper under the shrub patches compared with themicrophytic crust. When the microphytic crust was destroyed by simulatedtrampling, the runoff coefficient declined to 13%, and there was no significantdifference in water penetration between shrub and crust patches. Completedestruction of the shrub hummocks and crust by cultivation resulted in adeclinein the runoff coefficient to 6%. The result of sustained disturbance in thesepatchy Negev shrublands is a breakdown in spatial heterogeneity, a loss ofecosystem function, a reduction in ecosystem goods and services such as plantdiversity and production, and ultimately a reduction in pastoral productivity.These results reinforce the view that microphytic crusts are critical for theefficient operation of the Shikim water harvesting system.Given that practices such as cultivation and trampling which disturbmicrophyticcrusts result in enhanced infiltration, crusts should be left intact tomaximisethe water harvesting efficiency in these desert landscapes.This revised version was published online in May 2005 with corrections to the Cover Date.  相似文献   

免耕抛栽水稻源库特性研究   总被引：3，自引：0，他引：3  

韦善清  徐世宏  李如平  郎宁  江立庚  董登峰  张平刚  陈念平  秦华东  陆福勇 《中国农学通报》2005,21(9):237-241

近些年来,水稻免耕抛秧栽培在中国广西等部分地区发展迅速。为了探讨免耕抛栽水稻产量形成特点,以金优253(OryzasativaL.)为试验材料,以常耕抛栽水稻为对照,从叶面积大小、剑叶光合速率与衰老、库的大小及源库比率等方面研究了免耕抛栽水稻的源库特性。结果表明,免耕抛栽水稻早、晚季产量分别为5.97t/hm2和7.53t/hm2,常耕抛栽水稻分别为6.19t/hm2和7.63t/hm2,其产量差异在早季和晚季均不显著。与常耕抛栽水稻相比,免耕抛栽水稻的每穗总粒数和单位面积上的总粒数较多,各生育期的叶面积指数较大,灌浆期剑叶光合速率、蒸腾速率、气孔导度、叶绿素含量较高,而过氧化物酶和过氧化氢酶活性及丙二醛的含量较低,在生理上存在一定的优势。但是,免耕抛栽水稻的源库协调能力较差,粒叶比和结实率下降,致使免耕抛栽水稻在产量上表现出一定的劣势。免耕抛栽水稻粒叶比和结实率的下降是由于其生产的干物质更多地分配在叶片中、贮藏在茎鞘中的干物质在抽穗后向穗部运转的能力较差造成的。  相似文献   

The floral system of tomato     

D. Hareven  T. Gutfinger  L. Pnueli  L. Bauch  O. Cohen  E. Lifschitz 《Euphytica》1994,79(3):235-243

The tomato floral system is distinguished from that of Arabidopsis and Antirrhinum in several ways. The shoot is a sympodium, the first flower of the inflorescence is apical and no bracts are formed. We discuss the possible function of genes affecting growth habit and inflorescence development and analyze in detail the unique developmental alterations caused by inhibition or ectopic expression of tomato-specific MADS-box genes. Preliminary analysis of transgenic tomato plants expressing an alien homeotic gene and several different chimeric genes of the MADS-box family is also reported.  相似文献   

干旱对玉米穗发育及产量的影响   总被引：6，自引：2，他引：6  

李叶蓓  陶洪斌  王若男  张萍  吴春江  雷鸣  张巽  王璞 《中国生态农业学报》2015,23(4):383-391

干旱作为影响玉米产量的环境因素之首,对玉米植株形态、物质积累、生理作用、性器官发育等方面产生影响,最终降低穗粒数、粒重,导致产量降低。以雌雄穗发育为研究重点,本文综述了不同时期干旱对雌雄穗性状及开花吐丝间隔期的影响。玉米开花前遭遇干旱,延缓雌雄穗发育进程,减少分化小花数,增加籽粒败育,导致穗粒数降低;抽雄吐丝期间遭遇干旱,导致雄穗抽出困难、吐丝延迟,使开花吐丝间隔期拉长,严重时导致花粉、花丝超微结构发生改变,影响玉米授粉、受精过程,最终导致秃尖形成,穗粒数降低;灌浆期遭遇干旱导致叶片早衰,光合产物积累不足,籽粒灌浆受阻,粒重降低,最终均会导致产量下降。从源库关系角度分析,玉米灌浆期前干旱导致玉米产量降低的主要原因是穗粒数降低导致的库强不足;而灌浆期干旱主要是叶片早衰等营养器官发育受阻,限制同化物的积累及转运,此时源不足限制了产量的增加。  相似文献