高梁同源四倍体及其杂交处的细胞遗传学研究   总被引：2，自引：0，他引：2  

张继益  蒋观敏 《华北农学报》1997,12(3):1-6

对同源四倍体高梁品系和杂交种的细胞学观察发现，其减数分裂的各个时期均有特异性。具体表现在前期Ｉ有３．９４％的ＰＭＣ中存在多个核仁，其中以双核仁形式出现的频率最高；终变期－中期具有不同的染色体构型，可观察到同染色体四种组成形式，后期Ｉ出现大量落后染色体，其中以单价体提前分离造成的染色体落后较为常见，单价染色体落后较少；前期Ⅱ和四分体时期可观察到核外染色体；中期Ⅱ发现有部分染色体不排列于赤道板上；后期  相似文献   

春小麦幼穗分化进程及其与植株生长发育的关系   总被引：7，自引：0，他引：7       下载免费PDF全文

张玉贵 刘凯刘克礼  高聚林张铁山 张永平 《麦类作物学报》2003,23(3):58-63

为了给春小麦高产栽培提供理论依据，研究了水浇地不同品种在不同年份、地区及农艺栽培措施下的幼穗分化规律及其与植株生长发育的相关性．结果表明。春小麦幼穗分化开始于出苗后的ll～16d，穗分化全过程持续32～41d，不同品种之间以及同一品种在不同水肥条件下均存在较大差异。随着密度的增加，幼穗分化提前，随着施肥量的增加，幼穗分化推迟，分化持续天数延长，氮、磷、钾肥合理配施对促进穗分化的效应明显。春小麦幼穗分化进程与生育时期、叶龄指数具有显著的相关性，叶龄指数可作为判断春小麦幼穗分化进程和实施栽培措施的形态指标．  相似文献   

应用间接血凝试验检测水牛伊氏锥虫病抗体消长的研究     

刘耀兴  张观斗 《兽医大学学报》1992,12(1):78-80

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2018,期待茶叶市场的新与变     

暗中观茶 《茶世界》2018,(1)

正2017年,我们有一个共同的话题——"新零售"。但是,新零售到底是什么?其实目前市场还没有统一完整定义。形成共识的是,当下社会正进入一个消费市场创新,技术应用高发期,各行各业都在书写自己的"新零售"标准。茶叶行业在2018年的表现形态,可能跟2017年也会有差别。  相似文献   

Effects of Dietary Coated Sodium Butyrate on Growth Performance,Antioxidant Capacity and Inflammatory Response of Broilers under Cyclically Heat-Stress Condition北大核心CSCD     

万根黎观红许兰娇瞿明仁 《动物营养学报》2023,(1):211-220

This experiment investigated the effects of dietary coated sodium butyrate (CSB) on the growth performance, antioxidant capacity and inflammatory response of broilers under cyclically heat-stress condition. The experiment selected 500 one-day-old Arbor Acres (AA) broilers, and when routine immunization and rearing to 21-day-old, four hundred and fifty healthy and similar body weight broilers were selected and randomly divided into 5 groups with 6 replicates per group and 15 chickens per replicate. Five groups were divided into one normal temperature group (NT group), one heat stress group (HS group) and three heat stress and adding CSB groups (HS+CSB groups) . Broilers in the NT group were raised in room temperature environment [(24± 2) °C], and fed a basal diet. Broilers in the HS group and HS+CSB groups were raised in a daily high temperature environment (28 °C -36 °C -28 °C), and fed diets supplemented with 0, 300, 600 and 900 mg / kg CSB in the basal diet, respectively. The experiment lasted for 14 d. The results showed as follows: 1) compared with the NT group, cyclically heat-stress extremely significantly reduced the average daily feed intake and average daily gain of broilers (P < 0. 01) . Under the cyclically heat-stress condition, the addition of 900 mg / kg CSB significantly increased the average daily gain and average daily feed intake of broilers (P < 0.05), and the addition of 600 mg / kg CSB significantly increased the average daily gain of broilers compared with HS group (P<0.05) . 2) Compared with the NT group, cyclically heat-stress significantly or extremely significantly decreased serum glutathione peroxidase (GSH-Px), catalase (CAT) and superoxide dismutase (SOD) activities and total antioxidant capacity (T-AOC) of broilers (P<0.05 or P<0.01), and significantly or extremely significantly increased serum lactic dehydrogenase (LDH) and creatine kinase (CK) activities and the content of malondialdehyde (MDA), α1-acidoglycoprotein (α1-AGP), endotoxin (ET) and thiobarbituric acid reactive substance (TBARS) (P < 0. 05 or P < 0. 01) . Under the cyclically heat-stress condition, compared with the NT group, the addition of 900 mg / kg CSB significantly increased the serum GSH-Px, CAT and SOD activities and T-AOC (P < 0. 05), and significantly or extremely significantly decreased the serum LDH activity and α1-AGP, ET and TBARS contents of broilers (P < 0. 05 or P < 0. 01); the addition of 600 mg / kg CSB significantly increased the serum CAT and SOD activities (P<0.05), and extremely significantly decreased the serum LDH activity of broilers (P<0.01); the addition of 300 mg / kg CSB significantly increased the serum CAT and SOD activities and T-AOC of broilers (P < 0. 05) . 3) Compared with the NT group, cyclically heat-stress extremely significantly increased the serum contents of pro-inflammatory cytokines interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-8 (IL-8) of broilers (P<0.01) . Under the cyclically heat-stress condition, compared with the NT group, the addition of 900 mg / kg CSB significantly or extremely significantly reduced the serum IL-6, TNF-α, IL-1β and IL-8 contents of broilers (P < 0. 05 or P < 0. 01), and significantly increased serum transforming growth factor-β (TGF-β) content (P<0.05); the addition of 600 mg / kg CSB significantly or extremely significantly reduced the serum IL-6 and TNF-α contents of broilers (P<0.05 or P<0.01); the addition of 300 mg / kg CSB significantly reduced the serum TNF-α content of broilers (P<0.05) . Above results indicate that the addition of CSB in the diet can improve the growth performance of broilers under the cyclically heat-stress condition by increasing the antioxidant capacity and alleviating the inflammatory response, and adding 900 mg / kg CSB to the diet in this experiment has the best effect. © 2023 Chinese Journal of Animal Science and Veterinary Medicine Co., Ltd. All rights reserved.  相似文献   

5种药剂防治玉米草地贪夜蛾田间药效试验     

李冬霞  黄校华  梁赵秀  刘祥坤  杨世观  邓钦阳  张小燕 《广西植保》2019,32(4)

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天水地区15个马铃薯新品种比较研究     

王鹏  王德贤  李芳弟  何二良  郭天顺  颉炜清  齐小东  观永平  吕汰 《安徽农业科学》2015,(28):52-54

[目的]筛选适宜天水地区种植的优良马铃薯新品种.[方法]通过小区试验比较15个马铃薯新品种的生育期、抗病性能、产量及经济性状.[结果]15个供试品种中,云薯107、云薯202、天10-8-44田间长势好,抗病性较强,商品性状好,产量为13 740.75～ 16 875.45kghm2,较对照天薯10号增产66.81％～104.86％,商品薯率达80％以上.[结论]云薯107、云薯202、天10-8-44适宜在天水地区推广种植.  相似文献   

玉米密植和营养改良之研究Ⅰ.密度对玉米产量和营养的效应   总被引：12，自引：2，他引：12  

张永科; 何仲阳; 马永平  孙茂; 张雪君; 吴金平 《玉米科学》2005,13(3):087-090

4个直立叶型杂交种、3个种植行距穴67cm等行条播、50cm等行条播、六角形穴播雪、3个密度穴6.0万株/hm2、7.5万株/hm2、9.0万株/hm2雪的田间试验结果表明:影响玉米产量潜力提高的主要因素是密度,其次为行距,再次为品种;在试验实施的密度、行距、品种各因素处理中,玉米杂交种产量均随密度的增大而增加,玉米营养面积随密度的增大而变小。  相似文献   

春小麦源库特性及其关系的研究（Ⅱ）——群体库源比及其与产量的关系   总被引：6，自引：0，他引：6  

刘克礼翟利剑  高聚林张永平 刘景辉 《麦类作物学报》2003,23(4):63-65

为了给春小麦高产栽培提供理论依据,通过试验对两个春小麦品种在不同密度、施肥量处理下群体库源比值(粒叶比)在产量形成中的作用和相互关系进行了系统的研究。结果表明,在不同处理条件下,春小麦的经济系数均随密度和施P量的增加而降低;随施N量的增加,永良4号经济系数表现出降低的趋势,但内麦19呈增加趋势．经济系数高,经济产量均相对较高。粒叶比随密度、施N量、施P量的增加而降低,但在叶面积相近的情况下,粒叶比高的产量高。因此,在合理的栽培技术措施下,实现源、库的协调是小麦获得高产的生理基础。叶片单位面积负荷量(粒数／叶)与叶片单位面积有效生产量(粒重／叶)呈极显著正相关。在适宜的群体叶面积指数范围内,采取优化栽培措施,争取形成较多的结实粒数(库容),并提高粒重(库的充实度),是实现高产的有效途径。  相似文献   

网箱培育蟹苗试验   总被引：1，自引：0，他引：1  

梁义标任永平  江宏银陈少华 《淡水渔业》1988,(3):32-32

<正> 近年来,洪湖市因人工繁殖河蟹获得成功,促进了河蟹养殖的发展,池塘养蟹从几十亩发展到几百亩。随着成蟹养殖的发展,需要培育大批优质的种苗。为此,1987年我们在黄家口永宁湖百亩鱼蟹混养池中用网箱进行了从大眼幼体到幼蟹的强化培育试验。现将试验结果介绍如下。  相似文献