粤西地区冬季辣椒病毒病发生与防治

冬季辣椒病毒病主要受辣椒品种、气候条件、椒田环境及栽培管理等因素的影响。尖椒品种较圆 (甜 )椒品种的抗病性强 ,青皮尖椒较黄皮尖椒的抗病性强 ;冬季高温干旱 ,病害发生早而且严重 ,扩展速度快 ;椒田在林区或蔗地旁 ,其病害发生较在平原地的椒田普遍严重。在病毒病发生初期 ,及时防治传毒介体 ,用3.85%病毒毖克等药剂连续防治 2～3次 ,对抑制病毒病的扩展蔓延有较好的效果。     

三唑酮种衣剂对小麦白粉菌侵染和非侵染位点硅等元素含量的影响

 借助扫描电子显微镜-X射线能谱分析方法从超微结构和元素水平观测了三唑酮种衣剂包衣处理和空白对照的小麦幼苗上白粉病菌侵染及非侵染位点硅等元素含量的变化。结果表明,接种后20~36 h内三唑酮种衣剂处理的麦苗侵染位点细胞内元素硅含量由5.204%上升为42.064%,非侵染位点由5.821%上升为12.342%;空白对照中侵染位点元素硅含量由低于检测水平上升为17.388%,非侵染位点接种后36 h时为19.460%。在处理和空白对照的麦苗上侵染和非侵染位点均检测到了含量不等的磷、硫、氯等元素存在。     

禾谷镰刀菌接种小麦幼芽及致病力鉴定的初步研究

 由镰刀菌引起的赤霉病是危害小麦、大麦、燕麦、黑麦等禾谷类作物的一种重要病害,广泛分布于世界温暖潮湿地区。在我国赤霉病发病区,禾谷镰刀菌(Fusarium graminearum Schwabe)是主要致病菌。     

林间释放平腹小蜂防治银杏大蚕蛾研究

笔者于1999－2000年在城口银杏大蚕蛾发生区释放用其卵繁育的平腹小蜂防治银杏大蚕蛾，结果表明：放蜂区虫卵寄生率明显提高，其校正寄生率为69.30%，是一种可利用的天敌昆虫。可在银杏大蚕蛾发生区内推广应用。     

节瓜蓟马的新天敌——中华微刺盲蝽

首次发现中华微刺盲蝽Campylomma chinensis Schwh捕食节瓜蓟马Thrips palmi Karny且对田间节瓜蓟马种群数量的减少起重要作用。本文研究了该虫的形态特征、捕食过程和取食范围。结果表明中华微刺盲蝽为多食性昆虫，能取食多种小型昆虫及多种昆虫的卵：在田间，中华微刺盲蝽与节瓜蓟马数量的跟随现象明显；通过释入盲蝽，能使节瓜蓟马种群数量减少。     

三穗鸭兴衰的启示--必须走产业化道路

三穗鸭又称三穗麻鸭,是我国五大蛋系地方优良品种之一.三穗鸭主要产于三穗及周边县市境内,它以生长快、成熟早、产蛋多、觅食力强、耐粗放、肉质细嫩、味美鲜香而闻名海内外.三穗县是三穗鸭的泽源地和主产区,鸭源丰富,自然条件优越,群众养鸭历史悠久.稻田坝区,村村寨寨,组组户户立杆牧鸭.1994年以前,该县三穗鸭的饲养量一直是在40万羽上下徘徊,三穗鸭的发展处于徘徊时期.1994年,县委、县政府围绕"八七扶贫攻坚计划",提出建立三穗鸭生产基地,培植支柱产业的发展思路,采取政策鼓励、资金扶持、技术指导、市场引导和个体、集体、国家一齐上,圈养鸭、圈牧养鸭规模化等措施,经过几年的努力,养鸭业迅速发展起来.据县农业部门调查统计,1997年底该县已建立商品肉鸭基地示范村7个,养鸭专业户180户,饲养肉鸭15.3万羽,蛋鸭1.2万羽.通过基地示范村、示范户的带动,全县养鸭户达1.3万户,鸭的饲养量达83万羽,创历史最高水平.周边的天柱、石阡、玉屏、新晃等县的鸭饲养量也成倍增长,1997年,预计三穗及周边县市鸭的饲养量达200万羽.三穗鸭的发展处于兴盛时期.     

蔗糖对香石竹切花的保鲜效果

保鲜剂中蔗糖浓度分为4个处理，对照（CK）：0％蔗糖＋50ppm次氯酸钠；A：1％蔗糖＋50ppm次氯酸钠；B：2％蔗糖＋50ppm次氯酸钠；C：3％蔗糖＋50ppm次氯酸钠。把香石竹切花插入不同蔗糖浓度的保鲜剂中，进行切花寿命比较试验。结果表明，蔗糖浓度为3％的保鲜剂对香石竹的保鲜效果最佳，为12．8d，与对照（7．93d）相比明显延长。     

磷肥用量对甜玉米磷素吸收利用的影响

Understanding the phosphorus (P) absorption mechanism is the premise for high P utilization and high crop yield. In this study, the effects of different P rates (0, 37.5, 75, 150, and 300 kg hm^-2, expressed as P0, P1, P2, P3, and P4, respectively) on sweet corn yield, biomass and P accumulation and tissue distribution, P transportation and P utilization were studied using a two-year P gradient positioning field experiment. Our results showed that P application significantly increased the fresh ear yield of sweet corn, but the yield difference among different P application rates (P1-P4) was not significant from 2018 to 2019 compared with P0 treatment. P application significantly increased the biomass and P accumulation of sweet corn plants at jointing, silking and fresh eating stages, respectively. In addition, P accumulation in grain was not significant different, which accounting for 42% of plant P accumulation. With P application, the contribution rate of P assimilation to the ear P accumulation was 57.3%-93.0% after anthesis, while the fresh ear yield per P accumulation, P physiological efficiency, agronomic efficiency, recovery efficiency and partial productivity decreased with P rates. Considering the yield and utilization efficiency of phosphate fertilizer, the supply of 37.5 kg hm^-2 of phosphate fertilizer can meet the needs of high yield and efficient utilization of phosphate fertilizer in sweet corn in this experiment.     

Experimental Pathological Study of Acute African Swine Fever

To study the clinicopathology and histopathology of African swine fever (ASF), and to explore the internal relationship between pathological changes and disease occurrence and development and its pathological mechanism, 13 Landrace pigs with bodyweight about 20 kg were intramuscular injected with African swine fever virus (ASFV), strain Pig/HLJ/18 at a dose of 10²HAD₅₀·mL^-1. During the experiment, all the dead pigs were systematically dissected and sampled, paraffin sections were produced, and haematoxylin-eosin staining was performed. Clinicopathological evaluation standards for acute ASF were established, then pathological lesions (classification variables) were expressed by counting frequency and percentage, and the lesion degree (continuous variables) was graded and scored according to different pathological changes of various tissues and organs. The results showed that all infected pigs were in line with the clinical characteristics of ASF, including acute, febrile and highly infectious, with a 100% incidence rate and 100% mortality. The dead pigs showed typical characteristics of septicemia, cadavers prone to corruption, blood clotting adverse or hemolysis, rigor mortis incomplete. The main pathological lesions were hemorrhagic necrotizing lymphadenitis, acute inflammatory splenomegaly (septic spleen), cerebral edema, pulmonary edema and lung consolidation et al. The spleen and lymphonodus are the target organs attacked by ASFV, with the most significant lesions, the earliest occurrence time, the longest duration and the highest frequency. The most prominent pathological changes are blood circulation disorders, including multiple pathological manifestations such as edema, hyperemia, congestion, hemorrhage, infarction, disseminated intravascular coagulation (DIC), and the most important characteristics are hemorrhagic lesions. The inflammatory reaction of lymphocytic exudation caused by ASFV runs through the whole process, especially in the middle and later stages of the course. The results suggest that the main pathological process of acute African swine fever is a typical immune/inflammatory cascade reaction and severe systemic blood circulation disorder, which resulted in the high incidence rate and high mortality rate of acute ASF.     

茄子新品种驻茄15号的选育

驻茄15 号是以自交系P04-11 为母本，以高代自交系驻Q-25 为父本配制而成的中早熟绿茄一代杂种。植株生长势强，果实卵圆形，纵径15.0 cm 左右，横径10.6 cm 左右，平均单果质量0.52 kg，果皮绿色、光亮，肉质硬度中等，商品性好，一般每667 m² 前期产量1 100 kg 左右，总产量5 300 kg 左右，田间对青枯病、绵疫病、黄萎病的抗性强于对照郑研早青茄，适宜河南省及周边省份春、秋设施及露地栽培。