黑犏牛产奶量与气象因子的相关分析

<正> 黑犏母牛生产性能的主要指标是产奶量,而产奶量的高低,受川西北高寒牧区环境因素的影响很大。牧区暖季,是泌乳母牛的产奶盛期,每年从4月下旬开始产奶,日产奶量由低逐渐升高,再由高逐步降低,直至11月中下旬停止产奶。这种产奶的量变过程恰与许多生态因子的量变过程大体一致。由此表明,黑犏母牛日产奶量的变化规律与生态因子的变化规律之间     

远射程风送式喷雾机在赣南丘陵山地脐橙园病虫害防治中的应用

为探索大型喷药机械在赣南丘陵山地脐橙园病虫害防治中的应用,采用远射程风送式喷雾机进行丘陵山地脐橙园病虫害防治试验。结果表明,与传统动力喷雾器比较,丘陵山地脐橙园采用远射程风送式喷雾机进行病虫害防治,平均每株树可节省喷药成本0.52元/株;在多雨季节能更好地抓住时机,及时喷药,提高了病虫害防治的时效性;作业工人劳动强度较小,安全性高;有效控制柑橘潜叶蛾、红蜘蛛等的为害。     

不同保果方式和气象因子对鲍威尔脐橙冬季落果的影响

本研究在保果剂（含2,4-D、杀菌剂、杀螨剂、叶面肥）的两种处理方式下,调查了鲍威尔脐橙在重庆奉节铁佛果园和巫山福田果园两个点的冬季落果情况,结果表明,自然情况下,奉节铁佛果园的鲍威尔脐橙落果率明显低于巫山福田果园的落果率,至翌年2月底,后者的落果率是前者的5倍左右;和对照相比,11月和12月上旬喷两次保果剂处理能够明显降低脐橙的落果率。结合两个点的不同生态气候条件,对落果的原因进行了分析,认为低温特别是-2℃温度持续时间的长短是影响落果的主要原因。     

夏秋气象因子对奶牛养殖的影响及应对措施

夏秋季节危害性气象因素很多,有害的气象因子不仅影响奶牛的产奶量,也影响奶牛的生长、发育、繁殖和健康,恶劣气象条件甚至造成奶牛功能性障碍,严重的还会导致死亡。本文通过剖析这些不利气象因子对奶牛的危害,指出应积极主动采取有效措施,减少不利因素的危害,提高奶牛养殖的经济效益。     

夏河县羔羊成活与气象因子相关研究

夏河县羔羊成活与气象因子相关研究李统英（甘肃夏河县气象局７４７１００）张瑛（夏河县农业区划办）前言＊本文研究对象与夏河县藏系草地型绵羊。夏河县地处青藏高原东北端，是经营草原畜牧业为主的高寒牧业县。境内环境严酷，大部分地区海拔超过３０００米，＊虽然光照...     

赣南脐橙黄龙病相关内生菌的筛选及培养

基于高通量测序技术,对不同时期的患病脐橙树进行内生菌群结构分析比对,寻找黄龙病相关内生菌,然后利用不同培养基对内生菌进行富集并选择合适的培养基用于内生菌分离和纯培养。结果表明,5种菌随着患病时间的增长而增多,分别属于代尔夫特菌属（Delftia）、不动杆菌属（Acinetobacter）、假单胞菌属（Pseudomonas）、伯克霍尔德菌属（Burkholderia）和微杆菌属（Microbacterium）。经筛选后,选取NB果汁培养基和叶片培养基用于5种内生菌的富集、分离纯化和培养。植物内生菌在植物生长和抗病害方面都起着重要的作用,通过本文中的方法能有效的筛选并培养与柑橘黄龙病相关的内生菌,我们的结果将促进对柑橘黄龙病防治的研究。     

宁红茶区茶园蜘蛛群落及动态分布调查

茶园蜘蛛是控制茶树害虫种群的重要天敌,栽培、管理方式对蜘蛛群落的多样性影响重大。保护蜘蛛、研究蜘蛛是未来茶园害虫防治的发展方向。     

2009产季赣南脐橙出口回顾与对策分析

赣南脐橙是我国具有国际竞争优势的农业主导产业,促进出口是建立和完善赣南脐橙市场营销体系的重要目标。文章通过回顾2009年产季赣南脐橙出口情况,分析赣南脐橙出口存在的问题,并从政府层面就下一阶段如何做好赣南脐橙出口工作提出对策与建议。     

河北省坝上高原地区绵羊消化道线虫优势虫种季节动态研究

河北省坝上高原地区完全放牧条件下的绵羊消化道线虫优势虫种(捻转血矛线虫、羊仰口线虫和食道口线虫)季节动态：幼虫的感染强度在温暖的4～9月最低，而寒冷的10～3月较高；成虫的感染强度在6～9(或8)月最低。血矛线虫4～6月和9月～次年1月感染强度较高，羊仰口线虫除6～8月外其余各月份感染强度较高。食道口线虫4～6月为感染强度的高峰期。     

赣南脐橙产区果园土壤有效硼含量的现状与分析

对赣州市18县市区1275个脐橙果园土壤样本中的有效硼含量分析,结果表明：土壤有效硼平均含量为0.16mg/kg,缺硼比例为87.1%;土壤硼状况最好的龙南县其有效硼平均含量为0.26mg/kg,缺硼比例是64.7%;缺硼最严重的章贡区,其土壤有效硼平均含量仅为0.09mg/kg,南康县缺硼比例高达97.8%;脐橙的三个产量大县,信丰、寻乌、安远的土壤有效硼平均含量分别为0.18mg/kg、0.16mg/kg、0.15mg/kg,缺硼比例各占77.3%、86.2%、91.7%。     

赣南脐橙果园土壤有机质变化特征研究

以赣南脐橙18个县（市）果园为采样区,共采集了果园土壤农化样1405份和背景样229份,测定了土壤的有机质含量,并从果园土壤有机质的区域分布特征、有机质随土壤类型以及种植年限的变化特征进行统计分析。结果表明：不同种植区域果园土壤有机质含量分布存在较大差异,土壤农化样有机质含量变幅在1.01～47.58 g/kg之间,81％的果园土壤表现为有机质缺乏;有机质的含量与土壤本身的结构和特性紧密相关,紫色土有机质缺乏表现最明显;对不同种植年限果园,随园龄增加,在前10年内土壤有机质含量明显提高,之后稍有下降并趋于稳定。基于土壤有机质变化特征及对果园的现状调查,提出了提高果园土壤有机质的主要技术措施。     

赣州脐橙中农药残留及其分布特征

本研究采集江西赣州地区18个区县中110个乡镇的788个脐橙样品,采用QuEChERS技术结合GC/MS-MS和HPLC-MS/MS测定样品中166种农药残留,揭示江西赣州地区脐橙中农药残留现状及其地理分布特征。结果表明:（1）样品中检出18种农药残留,其中啶虫脒、多菌灵、咪鲜胺、杀扑磷、甲基硫菌灵、氧化乐果等检出率较高;（2）赣州的寻乌、龙南、赣县和石城的脐橙样品中农药检出率很高,阳性样品达到60%以上,而兴国和上犹的检出率较低;（3）脐橙果肉部分和果皮部分的农药残留量存在差异。(4) 仅有7个样品果肉部分的氧化乐果残留量超过国家标准的限量要求,占检测样品总数的0.8%,说明赣州脐橙还是比较安全的。     

Molecular identification,morphological characterization and new insights into the ecology of larval Pseudoterranova cattani in fishes from the Argentine coast with its differentiation from the Antarctic species,P. decipiens sp. E (Nematoda: Anisakidae)

Larvae of the genus Pseudoterranova constitute a risk for human health when ingested through raw or undercooked fish. They can provoke pseudoterranovosis in humans, a fish-borne zoonotic disease whose pathogenicity varies with the species involved, making their correct specific identification a necessary step in the knowledge of this zoonosis. Larvae of Pseudoterranova decipiens s.l. have been reported in several fish species from off the Argentine coasts; however, there are no studies dealing with their specific identification in this region. Here, a genetic identification and morphological characterization of larval Pseudoterranova spp. from three fish species sampled from Argentine waters and from Notothenia coriiceps from Antarctic waters was carried out. Larvae were sequenced for their genetic/molecular identification, including the mitochondrial cytochrome c oxidase subunit II (mtDNA cox2), the first (ITS-1) and the second (ITS-2) internal transcribed spacers of the nuclear ribosomal DNA, and compared with all species of the P. decipiens (sensu lato) species complex (sequences available in GenBank). Further, adults of Pseudoterranova spp. from the definitive host, the southern sea lion, Otaria flavescens, from Argentine and Chilean coasts were sequenced at the same genes. The sequences obtained at the ITS-1 and ITS-2 genes from all the larvae examined from fish of Argentine waters, as well as the adult worms, matched 100% the sequences for the species P. cattani. The sequences obtained at mtDNA cox2 gene for Antarctic larvae matched 99% those available in GenBank for the sibling P. decipiens sp. E. Both MP and BI phylogenetic trees strongly supported P. cattani and P. decipiens sp. E as two distinct phylogenetic lineages and depicted the species P. decipiens sp. E as sister taxon to the remaining taxa of the P. decipiens complex. Larval morphometry was similar between specimens of P. cattani from Argentina, but significantly different from those of P. decipiens sp. E, indicating that larval forms can be distinguished based on their morphology. Pseudoterranova cattani is common and abundant in a variety of fish species from Chile, whereas few host species harbour these larvae in Argentina where they show low levels of parasitism. This pattern could arise from a combination of factors, including environmental conditions, density and dietary preferences of definitive hosts and life-cycle pathways of the parasite. Finally, this study revealed that the life-cycle of P. cattani involves mainly demersal and benthic organisms, with a marked preference by large-sized benthophagous fish.