山东产区套袋苹果病虫害综合防控“164”农药减施模式的设计与应用     

李保华  门兴元  张振芳  王英姿  练森  李丽莉 《中国果树》2020,(2):1-5

针对山东产区套袋苹果的常见病虫害,设计了病虫害综合防控"164"农药减施模式,即1个重点生态防控期、6个化学防治关键期和4个病虫重点监控期。按"164"减药模式制定适用不同地区和采用不同农药公司药剂种类的具体防控方案,在栖霞、蓬莱等地的果园连续试验2年。结果表明:试验园全年用药9~14药次,与当地常规管理的对照园相比,化学农药使用量减少50%以上;试验园的病虫叶率和病虫果率都控制在5%以内,果园内无落叶现象;病虫防治效果、果实的产量和品质、优质商品果率等项指标,与当地常规管理的对照园无明显差异。  相似文献   

春笋幼竹期毛竹地上生物量格局及养分动态变化规律     

许庆标  郭宝华  范少辉  苏文会  赵建成 《热带作物学报》2014,35(8):1481-1486

研究毛竹关键生理阶段春笋幼竹期各龄级母竹地上生物量分配格局与养分动态变化规律,并同小年期的相应值进行比较。结果表明,该时期,光合器官竹叶生物量分配比例随竹株年龄增大而减小,其干质量占地上器官生物量干重的7.09%,比小年期的相应值增大了36.4%。在春笋幼竹生长初期,母竹叶片中氮含量呈下降趋势,而竹根中则略有升高,此后均趋于稳定;钾元素在母竹叶片中的含量随春笋幼竹生长而迅速升高,5月份达最大值12.21 mg/g,磷在叶片和根部的含量均较低。同小年期相比,含量最高的氮元素在叶、枝、秆、根中的含量均较低。春笋幼竹期,新竹的快速生长对母竹生物量格局与养分分配产生了重要影响。  相似文献   

产前运动对围产期奶牛生理代谢指标的影响     

江婧  马莉  骆巧  罗正中  沈留红  余树民  陶金忠  曹随忠 《中国畜牧兽医》2021,48(9):3183-3190

本试验旨在研究产前运动对围产期奶牛生理代谢指标的影响，为围产期奶牛健康管理提供科学指导和理论依据。试验选取年龄相似，体况评分、胎次和预产期相近的经产荷斯坦奶牛24头，随机分为试验组（TRT组）和对照组（CON组），每组12头，统一饲养管理。于预产期前21 d开始，TRT组奶牛每日09：00和16：00以<3 km/h的速度运动1 h，每头奶牛每日总运动量为（4.0±0.2） km/d；CON组自由活动。分别在预产期前21、7 d、分娩当天及产后7、30 d （分别记为－21、－7、0、+7和+30 d），于晨饲前采集血液，测定血浆中非酯化脂肪酸（NEFA）、β-羟基丁酸（BHBA）、葡萄糖（GLU）、甘油三酯（TG）、胆固醇（CHOL）、肌酐（CREA）及尿素（UREA）浓度。结果显示，试验期间，TRT组血浆NEFA、BHBA浓度与CON组相比均呈下降趋势（0.05<P<0.1），－7 d时TRT组NEFA浓度显著低于CON组（P<0.05）；TRT组血浆GLU浓度变化较CON组平稳，在＋30 d极显著高于CON组（P<0.01）；两组血浆TG浓度均在分娩当天急剧下降，产前血浆TG浓度均极显著高于分娩后各时间点（P<0.01），＋30 d时TRT组极显著高于CON组（P<0.01）；血浆UREA、CREA浓度在两组间无显著差异（P>0.05）。综上，以<3 km/h的速度进行运动（4.0 km/d±0.2 km/d），可有效降低围产期奶牛血浆NEFA和BHBA浓度，缓解能量负平衡（NEB）压力。  相似文献   

诱导Badila提早开花的主要气象因子初探     

董立华  周清明  段惠芬  杨李和  安汝东  桃联安  经艳芬  吴才文 《中国甜菜》2010,(3):4-5,8

通过连续两年人工诱导结果表明，提早诱导时间、暗期气温高低、光照期间破坏性高温天数是诱导Badfla提早开花的主要原因。  相似文献   

不同杂交中稻品种开花期耐高温性鉴定     

徐富贤  周兴兵  张林  蒋鹏  刘茂  郭晓艺  朱永川  熊洪 《中国稻米》2020,(1):41-45

2013年、2016年分别以40个杂交中稻品种为材料,在人工气候室和自然高温条件下鉴定了不同品种开花期的耐高温性。结果表明,人工气候室模拟高温下鉴定耐高温指数≥0.5的品种,两种条件下的耐高温指数呈极显著正相关;而人工气候室模拟高温下鉴定的耐高温指数≤0.49的品种,两种条件下的耐高温指数的相关性不显著,原因在于部分在人工气候室模拟高温下鉴定的不耐高温品种在自然条件下因花时早而避开了高温伤害,仍表现出较高的耐高温指数。根据开花期耐高温性可以把杂交水稻分为耐避双重型、耐高温型、避高温型和高温敏感型4种类型。  相似文献   

施肥对山地枣果维生素C含量的影响     

邓新为  刘萌  刘世鹏 《中国农学通报》2021,37(32):78-82

为了探究不同肥料、施肥次数对山地枣果维生素C含量的影响,筛选出适合枣树生长的施肥方案。本研究以狗头枣、骏枣、木枣3种山地枣果为材料,选用复合肥、生物有机肥、红枣专用肥、微生物菌肥分别在枣果生长的白熟期、青红期、成熟期进行不同施肥次数的施肥处理,用钼蓝比色法测定枣果在不同生长发育时期的维生素C含量。结果表明：对于狗头枣,在全年2次施用菌肥处理下,白熟期枣果维生素C含量达到最高,也显著提高了其青红期、成熟期维生素C含量;对于骏枣,在全年2次施用菌肥处理下,青红期和成熟期枣果维生素C含量达到最高,白熟期全年2次施用专用肥其维生素C含量达到最高。对于木枣,在白熟期全年2次施用专用肥可显著提高枣果维生素C含量,且达到最佳。在青红期全年2次施用菌肥处理可显著提高枣果维生素C含量,达到全组最高。在成熟期全年1次施用菌肥提高枣果维生素C含量的效果最佳且最为显著。对于3个品种枣果,在对其不同发育时期的枣树施肥时,全年采用2次施肥的方案可获得维生素C含量较高的枣果实,其中菌肥的效果尤为显著。  相似文献   

嘉道年间河费使用问题探析     

曹志敏 《安徽农业科学》2011,39(32):20295-20298

论述了嘉道时期河费激增的概况及其使用效率问题,认为河费除了治河所必需的部分以外,在清代形成了一个仰食河费的庞大社会阶层,影响了河费的正常使用。  相似文献   

Preemptive Analgesia,Including Morphine,Does Not Affect Recovery Quality and Times in Either Pain-Free Horses or Horses Undergoing Orchiectomy     

《Journal of Equine Veterinary Science》2017

Recovery quality and times from general anesthesia in horses may be influenced by surgery, analgesia with morphine or combinations of both. Twenty-three adult healthy horses were enrolled in this prospective experimental trial in a clinical setting and were randomly allocated to one of the following groups: anesthesia only (GA; n = 6), preemptive analgesia and anesthesia (GAA; n = 5), anesthesia and castration (GC; n = 6), or preemptive analgesia, anesthesia, castration, and intraoperative local analgesia (GCA; n = 6). All horses were sedated with intramuscular (IM) xylazine (0.5 mg/kg). Anesthesia was induced with intravenous (IV) guaifenesin (100 mg/kg) and thiopental (5 mg/kg) and maintained with isoflurane in oxygen. Animals in groups with preemptive analgesia received IM morphine (0.2 mg/kg) and dipyrone (10 mg/kg) and IV flunixin meglumine (1.0 mg/kg) immediately before sedation. Recoveries from general anesthesia were rope-assisted. Recovery scores (from 8 [excellent recovery] to 70 [worst recovery]) and times were compared between groups, using a one-way analysis of variance followed by a Tukey's test (P < .05). Mean ± standard deviation (SD) and range recovery scores were 22 ± 14 (8–45), 9 ± 2 (8–12), 14 ± 5 (8–22), and 12 ± 1 (10–13) in groups GA, GAA, GC, and GCA, respectively. Mean ± SD times to stand in minutes were 21 ± 10, 18 ± 7, 33 ± 12, and 35 ± 21 in groups GA, GAA, GC and GCA, respectively. No statistically significant differences were found for any of the variables. Neither preoperative administration of analgesics, including morphine, nor castration interfered with the recovery qualities and times in horses undergoing general anesthesia. Preemptive morphine did not worsen anesthetic recovery quality in horses.  相似文献   

Dynamics of Aggregate Stability Influenced by Soil Management and Crop Residues     

《Communications in Soil Science and Plant Analysis》2012,43(15-20):2565-2575

Abstract

The type of tillage and crop systems used can either degrade or cause a recovery of the structure of agricultural soils. The objective of this study was to determine the structural stability of the soil using mean weight diameter (MWD) of soil aggregates in three different periods of a succession of crops consisting of beans/cover plants/maize under no tillage (NT) and conventional tillage (CT) management systems. Soils were sampled at 0‐ to 5‐cm and 5‐ to 15‐cm depths in three periods (P1, P2, P3): 1) November 2002 (spring/summer), 2) April 2003 (beginning of autumn), and 3) December 2003 (end of spring/beginning of summer). Aggregate stability was determined by wet sieving. The effects of the tillage systems, vegetal residues, and sampling depths on the structural stability of the aggregates were assessed and then related to organic matter (OM) contents. Aggregate stability showed temporal variation as a function of OM contents and sampling period. No tillage led to high MWD values in all study periods. The lowest MWD values and OM contents were observed 4 months after the management of the residues of cover plants. This finding is consistent with the fact that at the time of the samplings, most of the OM had already mineralized. The residues of sunn‐hemp, millet, and spontaneous vegetation showed similar effects on soil aggregate stability.  相似文献   

杨树速生林适宜采伐期的测定研究     

邱宝刚  杜树尧  梁爱生  张国余  周俊荣 《防护林科技》2005,(Z1):27-27

确定杨树速生林适宜采伐期,与树种结构、林龄、林分密度和林木连年生长量有直接关系,当林分密度进入极限时,林木连年生长量开始从高峰下降,说明林分已进入适宜采伐期,实行适宜采伐期采伐作业,可获最佳经济效益。  相似文献