The effect of metabolic stress disinfection and disinfestation (MSDD) on ‘Hass’ avocado fruit physiology and mortality of longtailed mealybug (Pseudococcus longispinus)     

F. Zulhendri  L.E. JamiesonC.O. Perera  R.M. McDonaldP.G. Connolly  S.Y. QuekA.B. Woolf 《Postharvest Biology and Technology》2012,64(1):138-145

Metabolic stress disinfection and disinfestation (MSDD) is a potential quarantine treatment in which a combination of cycles of rapid decompression and compression are followed by exposure to ethanol vapour under decompression. The response of ‘Hass’ avocado (Persea americana Mill., cv. Hass) to MSDD treatment for control of longtailed mealybug (Pseudococcus longispinus) was investigated. The best treatment for the most resistant life stage (2nd/3rd instars) was 90-min MSDD treatment with 371 mg L⁻¹ ethanol. Early and late season ‘Hass’ avocados were subjected to MSDD treatments (with 371 mg L⁻¹ ethanol), or in air (control). Following the treatments, early season fruit were ripened at 20 °C and 25 °C. Half of the late season fruit were ripened at either 20 °C or 25 °C, and the remainder were stored at 5.5 °C for 6 weeks, then ripened at 20 °C. There were no significant difference in quality and rot incidence between non-treated controls and MSDD-treated fruit. The main disorders found were stem-end and body rots, vascular browning and flesh greying for the stored fruit. There were also no significant differences in fruit respiration rate or ethylene production. Thus, MSDD was shown to be a potentially ‘soft’ disinfestation treatment for surface pests of avocado.  相似文献   

施肥对山地红枣林土壤微生物区系及酶活性的影响   总被引：2，自引：0，他引：2  

栾晓波  徐福利  汪有科  李慧杰 《西北农业学报》2012,21(7):149-154

采用田间试验与室内分析方法,研究施肥对山地红枣林土壤微生物区系及酶活性的影响。结果表明,施肥显著提高不同土层(0～20cm、20～40cm和40～60cm)中土壤微生物数量和酶活性(P<0.05),单一施肥与氮磷钾配施对土壤微生物区系和酶活性的影响有显著差异(P<0.05)。红枣林在施肥处理下土壤细菌、放线菌和真菌数量较CK样地均有不同程度增加:0～20cm土层微生物数量变化明显,其中N221.0P2O5272.7K2O 303.0和N303.7K2O 180.5两组处理的效果最明显。施肥处理下的土壤磷酸酶、蔗糖酶、脲酶和过氧化氢酶活性均比CK有显著增加(P<0.05),N221.0P2O5272.7K2O 303.0和N303.7K2O 180.5处理的土壤磷酸酶和蔗糖酶活性最高,P2O5272.7处理的土壤脲酶和过氧化氢酶活性最高。土壤纵向分析表明,0～60cm土层土壤细菌、放线菌和真菌数量和土壤脲酶、磷酸酶、蔗糖酶活性均随深度增加而降低。N221.0P2O5272.7K2O303.0配施处理能明显提高枣园土壤微生物数量及磷酸酶和蔗糖酶活性。  相似文献   

Welfare implications of invasive piglet husbandry procedures,methods of alleviation and alternatives: a review     

MA Sutherland 《New Zealand veterinary journal》2013,61(1):52-57

Abstract

Iron administration, teeth clipping, tail docking and castration are common invasive husbandry procedures performed on piglets on commercial farms, generally within the first week of life. These procedures are performed to prevent potential health and welfare problems of piglets and/or the sow, or, with respect to castration, to enhance meat quality. The objectives of this review were firstly, to provide the rationale and scientific evidence for performing these procedures, secondly, to describe the welfare implications of these procedures, and lastly, to describe mitigation strategies or alternatives that can be used to eliminate or reduce the pain caused by these procedures. Administering supplementary iron is necessary to prevent anaemia in piglets and the procedure has a low welfare impact. The stated benefits of teeth clipping to prevent udder lesions do not appear to outweigh the risk from injury and infection in piglets following the procedure. Tail docking reduces the prevalence of tail biting, but does not eliminate this behaviour and the practice of tail docking can cause acute pain. Castration is primarily performed to reduce the occurrence of boar taint, but alternatives are now available that negate the need to perform this procedure. Teeth clipping, tail docking and castration all cause behavioural and physiological changes indicative of acute pain and can have potentially long-term negative consequences such as causing abscesses, lesions and the formation of neuromas. Therefore effective pain mitigation strategies (e.g. analgesia, local or general anaesthesia) that markedly alleviate the pain caused by these procedures are necessary to improve the welfare of piglets. Alternatively, if management practices are available that eliminate the need for performing these procedures altogether, then they should be adopted.  相似文献   

采伐剩余物处理方式对2代杉木林碳储量的影响     

陈杰 《福建林业科技》2019,(2):1-6,17

在福建南平第1代杉木成熟林中设置固定标准地,采伐前测定每个标准地碳储量,采伐后采用5种方式处理采伐剩余物:全部收获(移走地面上全部有机剩余物,包括树木、林下植被和枯枝落叶)、全树收获(收获树木的全部地上部分)、树干和树皮收获(仅收获树干与树皮)、加倍采伐剩余物(仅收获树干和树皮,将全树收获处理的树枝和树叶移到这个处理中)、炼山(仅收获树干和树皮,然后火烧采伐剩余物),随后采用常规方法营造第2代杉木林。试验后12 a,对不同处理生态系统碳储量进行研究。结果表明:12年生第2代杉木林乔木层碳储量大小顺序为:加倍采伐剩余物(61.03 t·hm-2)>全树收获(57.57 t·hm-2)>全部收获(55.64 t·hm-2)>树干和树皮收获(54.38 t·hm-2)>炼山(49.00 t·hm-2);土壤层(0~40 cm)碳储量大小顺序为:加倍采伐剩余物(99.49 t·hm-2)>全树收获(95.63 t·hm-2)>树干和树皮收获(94.81 t·hm-2)>全部收获(91.55 t·hm-2)>炼山(91.23 t·hm-2,与第1代杉木林采伐前相比,第2代12年生杉木土壤层(0~40 cm)碳储量除了全部收获处理降低0.04 t·hm-2外,其他处理均有少量增加,但差异均不显著。第2代12年生杉木林生态系统总碳储量大小顺序为:加倍采伐剩余物(162.80 t·hm-2)>全树收获(155.56 t·hm-2)>树干和树皮收获(151.24 t·hm-2)>全部收获(149.14 t·hm-2)>炼山(142.29 t·hm-2)。加倍采伐剩余物处理、全树收获处理、树干和树皮收获处理、全部收获处理生态系统碳储量分别比炼山处理高14.41%、9.33%、6.29%、4.81%,但差异均达不到显著水平(P>0.05)。  相似文献   

A soil‐quality index for soil from Mediterranean forests     

Manuela Andrs‐Abelln  Consolacin Wic‐Baena  Francisco R. Lpez‐Serrano  Francisco A. García‐Morote  Eduardo Martínez‐García  Marta I. Picazo  Eva Rubio  Jose L. Moreno‐Ortego  Felipe Bastida‐Lpez  Carlos García‐Izquierdo 《European Journal of Soil Science》2019,70(5):1001-1011

  相似文献   

Chemical and organic immobilization treatments for reducing phytoavailability of heavy metals in copper‐mine tailings     

Mohammad Jamal Khan  David L. Jones 《植物养料与土壤学杂志》2008,171(6):908-916

This study was conducted to evaluate the efficiency of diammonium phosphate (DAP), agricultural limestone (lime), and green‐waste compost mixed with 30% treated sewage sludge (GCS) applied alone or in combination as chemical immobilization treatment using tomato as a test crop. Mine waste was collected from an abandoned copper‐mine tailing site at Mynydd Parys, Anglesey (UK). Lime was applied at the rate of CaCO₃ equivalent (CCE, pH = 7), DAP at the rate of 23 g P per kg substrate, and 10% by weight, GCS as sole application. Half rate of each amendment was also tested as a combined treatment and an untreated substrate (control). Plant‐available metals (Cd, Cu, Fe, Pb, and Zn) were measured in substrate with conventional diethylenetriaminepentaacetic acid (DTPA) and sequential Ca(NO₃)₂ extraction. Plant–dry biomass yield was significantly (p < 0.001) increased by the combined application of all the three amendments while sole application of DAP reduced yield by 4‐fold compared to unamended soil probably due to P toxicity. Addition of lime reduced the DTPA‐extractable Cu, Fe, and Zn by 75%, 81%, and 85%, respectively, while Pb availability was reduced by 88% in combined DAP + lime + GCS treatment compared to control. The extraction capacity of DTPA was higher than that of Ca(NO₃)₂ by 3‐fold for Cu and Fe, 8‐fold for Pb, and 2‐fold for Zn. The leaf‐tissue concentrations of Cu and Fe were reduced by 77% and 83% in the lime + GCS amendment, respectively, while both Pb and Zn were reduced by 89% and 33%, respectively, in substrate treated with the combined application of all three amendments. These results suggest that alkaline amendments (both lime and GCS) were effective in reducing the phytoavailability of Cu, Fe, and Zn while DAP mixed with either GCS or lime was effective in reducing Pb availability.  相似文献   

小黑麦牧草产量与品质对施氮的响应   总被引：5，自引：0，他引：5  

董召荣  田灵芝  赵波  武德传  朱玉国 《草业科学》2008,25(5):64-67

研究了施氮对不同刈割时期小黑麦中饲237 Triticale cereale cv. Zhongsi 237的饲草产量及营养成分的影响.结果表明:施氮和刈割时期对中饲237的草产量均有明显的影响,施氮可显著改善刈割后中饲237的再生性,促进植株生长,提高二茬鲜草、干草产量,且差异达极显著水平,同时可提高饲草的粗蛋白、粗脂肪、氨基酸含量,降低粗纤维含量,改善饲草品质.起身期刈割的处理,其二茬草的草产量、粗蛋白、粗脂肪产量均高于拔节期刈割的处理.追施氮肥处理的粗蛋白含量及产量均大于未追施氮肥的处理,而中性洗涤纤维、酸性洗涤纤维含量小于未追氮肥的处理.  相似文献   

PAK-Abnahmen in Bodenproben verschiedener Altlaststandorte bei Aktivierung der autochthonen Mikroflora     

Sren Thiele  Gerhard W. Brümmer 《植物养料与土壤学杂志》1998,161(3):221-227

PAH decrease in soil samples from different polluted industrial sites by activating the autochthonous microflora In pot experiments under field conditions the PAH decrease in ten different soil samples from former industrial sites with differing PAH load were investigated over a period of 74 and 168 weeks. 15 out of 16 PAH according to US EPA (without acenaphthylene) were determined. Easily degradable organic matter, mineral fertilizers, synthetic surfactants and in some experiments also lime were added to the soil samples in varying amounts. Depending on the nature and quantity of the amendments, the biological activity and (co-)metabolic decomposition of PAH by soil microorganisms could considerably be increased. In the different soil samples a decrease of the initial PAH contents between 12 and 90% was achieved within 74 weeks. Even from 74 up to 168 weeks for some soil samples a remarkable further decrease of the PAH contents could be observed. The decrease of the extractable PAH with time is mainly caused by microbial decomposition and formation of nonextractable residues. This behavior can be fitted by two coupled exponential functions, one for an initial phase of rapid decomposition and the other for a subsequent phase of slow decomposition. Therefore, two different processes (I, II) determine the decrease of PAH. In the first week of the experiment the decomposition rates for process I amount to 4.2–88.3 and for process II to 0.06–5.3 mg PAH ? kg^?1 soil ? week^?1; in the 168th week they are no longer determinable for process I and amount to 0.05–2.3 mg ? kg^?1 ? week' for process II. Higher initial PAH contents often led to higher relative PAH decreases, but also to absolute higher contents of residues. The persistence of PAH is mainly determined by their bioavailability. PAH degradation is increased by the soil treatments. The addition of easily degradable organic matter (C/N ratio < 20) in a quantity of 30g ? kg^?1 (w/w) combined with the addition of nitrate and a surfactant most effectively increased the degradation of PAH. Raising the pH of a very strongly acidic soil sample revealed a maximum PAH decomposition at a pH of 6.  相似文献   

龙门式电驱动油菜薹收获机设计与试验     

廖宜涛  李运通  万星宇  廖庆喜  单伊尹  蒙哲靖 《农业机械学报》2022,53(12):147-159

针对油菜薹机械化收获装备匮乏的问题,设计了一种龙门式电驱动油菜薹收获机,实现油菜薹切割、夹抛、输送、收集、跨厢面遥控自走功能。阐述了收获机整机设计方案,设计了立式回转夹抛切割装置,确定了分禾器、割刀和夹抛辊结构参数;通过割台夹抛过程力学与运动学分析,明确了油菜薹切割、夹抛输送作业影响因素,确定了割刀、夹抛辊结构和运动学要求;搭建油菜薹收获试验台,以切割效果、输送效果为评价指标开展单因素试验和正交试验,结果表明当割刀转速为234r/min、夹抛辊转速为120r/min、喂入速度（机具前进速度）为0.56m/s时综合收获效果最佳。田间收获验证试验表明,设计的收获机作业效率可达到0.41hm2/h,综合切割效果为95.6%,综合输送效果为95.2%,满足油菜薹收获要求。该研究可为油菜薹机械化收获装备的结构设计优化提供参考。  相似文献   

Effect of potassium and manganese phosphites in the control of Pythium damping‐off in soybean: a feasible alternative to fungicide seed treatments          下载免费PDF全文

Marcelo A Carmona  Francisco J Sautua  Pablo E Grijalba  Mariano Cassina  Oscar Pérez‐Hernández 《Pest management science》2018,74(2):366-374

  相似文献