茉莉酸甲酯诱导柿树挥发物对红点唇瓢虫吸引力的持续效应

为明确茉莉酸甲酯(MeJA)诱导柿树(Diospyros kaki Linn.f.)挥发物成分的变化对蚧虫的天敌昆虫红点唇瓢虫(Chilocorus kuwanae Silvestri)吸引力的持续效应,应用3种剂量(20、100μL和200μL)的MeJA处理柿树,通过"Y"型嗅觉仪测试瓢虫的行为反应,并采用顶空收集和气质联用(GC/MS)分析挥发物的组成和相对含量。结果表明,MeJA可以诱导树体挥发物成分发生改变,对瓢虫产生吸引力,其持续效应可达1d以上。而不同剂量的处理组之间存在差异,高剂量组中萜烯类物质含量最多,在处理后3h瓢虫的趋性最强,相应的α-蒎烯含量高达34.05%。处理3～5d后吸引力显著下降,α-蒎烯等化合物的含量也逐渐减少。因此,茉莉酸甲酯的连续应用可以招引更多的瓢虫来控制蚧虫。     

Genetic mapping of bph20(t) and bph21(t) loci conferring brown planthopper resistance to Nilaparvata lugens St?l in rice (Oryza sativa L.)

Brown planthopper(BPH) is one of the most serious and destructive insect pests of rice in most rice growing regions of the world. In this study, two major resistance genes against BPH have been identified in an Oryza rufipogon (Griff.) introgression rice line, RBPH54. Inheritance of the BPH resistance in RBPH54 was studied by screening the resistance in parents, F1, F2 and BC1 generations against BPH biotype 2. A population of BC3F2 lines was developed and SSR markers were employed for the gene mapping, and new markers were designed for fine mapping of the resistance genes, while sequence information of BAC/PAC clones was used to construct physical maps of the genes. The results showed that the BPH resistance in RBPH54 was governed by recessive alleles at two loci, tentatively designated as bph20(t) and bph21(t). The locus bph20(t) was fine mapped to the short arm of chromosome 6 about 2.7 cM to the upper marker RM435 and 2.5 cM to lower marker RM540 and in a 2.5 cM region flanked by two new SSR markers BYL7 and BYL8 which were developed in the present study. The other BPH resistance locus bph21(t) was initially mapped to a region 7.9 cM to upper marker RM222 and 4.0 cM to lower marker RM244 on the short arm of chromosome 10. For physical mapping, the bph20(t)-linked markers were landed on BAC/PAC clones of the reference cv., Nipponbare, released by the International Rice Genome Sequencing Project. The bph20(t) locus was physically defined to an interval of about 75 kb with clone P0514G1. Identification and location of these two genes in the present study have diversified the BPH resistance gene pool, which give benefit to the development of resistant rice cultivars, and the linkage PCR-based SSR markers for the bph20(t) and bph21(t) genes would help realize the application of the genes in rice breeding through marker-assisted selection.     

Microsporidia in household dogs and cats in Iran; a zoonotic concern

Microsporidia in dogs and cats is primarily caused by the obligate, intracellular parasite Encephalitozoon cuniculi, which is a member of the phylum Microsporidia. The aim of the current study is the detection of this parasite in stool samples of small animals of Iran, by polymerase chain reaction. Microsporidia spp. was found in 31% (31/100) of dogs (E. cuniculi (18/100), Encephalitozoon bieneusi (8/100) and Encephalitozoon intestinalis (5/100)), and 7.5% (3/40) of the specimens obtained from cats were infected with E. bieneusi. Sequencing of PCR products confirmed these results. In conclusion, Microsporidia infection seems to be fairly common in pet animals of Iran, especially in dogs. This finding could indicate the importance of pet animals as zoonotic reservoirs of microsporidial human infections.     

Evaluation of bone healing in canine tibial defects filled with cortical autograft,commercial-DBM,calf fetal DBM,omentum and omentum-calf fetal DBM

The present study was conducted to compare the effects of xenogenic bovine fetal demineralized bone matrix (DBM), commercial DBM, omentum, omentum-calf fetal DBM, cortical autograft and xenogenic cartilage powder on the healing of tibial defects in a dog model to determine the best material for bone healing. Seven male adult mongrel dogs, weighing 26.2 ± 2.5 kg, were used in this study. Seven holes with a diameter of 4-mm were created and then filled with several biomaterials. Radiographs were taken postoperatively on day 1 and weeks 2, 4, 6, 8. The operated tibias were removed on the 56th postoperative day and histopathologically evaluated. On postoperative days 14, 42 and 56, the lesions of the control group were significantly inferior to those in the other group (p < 0.05). On the 28th postoperative day, the autograft group was significantly superior to the control and omentum groups (p < 0.05). Moreover, calf fetal DBM was significantly superior to the control group. There was no significant difference between the histopathological sections of all groups. Overall, the omentum and omentum-DBM groups were superior to the control group, but inferior to the autograft, commercial-DBM, calf fetal DBM and calf fetal cartilage groups.     

桑树中拮抗内生细菌的分离筛选及其抑菌机制

以小麦赤霉病菌为指示菌,进行桑树拮抗内生细菌的分离筛选,开展拮抗内生细菌的对峙培养和盆栽控病试验,并采用分光光度法检测SSY26拮抗菌引入小麦穗部,小麦穗组织中的多酚氧化酶(PPO) 、过氧化物酶(POD) 和苯丙氨酸解氨酶(PAL) 的酶活性。结果显示,SSY26菌株对小麦赤霉病菌具有较好的抑制作用,抑菌率达到58.65%,显微观察显示SSY26菌株可引起小麦赤霉病菌菌丝膨大、畸形,影响其正常生长;分子鉴定SSY26菌株为芽孢杆菌属微生物。小麦盆栽试验结果表明,第18 天时SSY26菌悬液对小麦赤霉病的防治效果为27.30% ,与化学药剂处理组没有显著差异,且桑树内生细菌SSY26引入到小麦穗部,可提高穗部组织中PPO、PAL及POD等防御酶活性。     

黄土丘陵区封禁对侵蚀土壤微生物生物量的影响

采用时空互代法,以典型侵蚀环境纸坊沟流域不同封禁年限的狼牙刺群落和杂灌群落为研究对象,选取放牧地和天然次生林为参照,分析了生态恢复过程中土壤微生物生物量、呼吸强度、代谢商及理化性质的演变特征。结果表明,封禁后土壤理化性质明显改善;微生物生物量随封禁年限的延长变化显著,阳坡随封禁年限增加土壤微生物生物量逐渐增加,25 a后微生物生物量碳、氮、磷较封禁前分别增加252%、161%和174%,但显著低于天然侧柏林,仅为其39.0%、41.8%和53.7%;阴坡封禁前10年微生物生物量迅速增加,随后增加幅度减缓,呈波动式缓慢上升趋势;封禁25 a后微生物生物量碳、氮、磷分别增加108%、93%和102%,但明显低于天然杂灌丛群落和辽东栎林,仅为辽东栎林的54.4%、49.1%和40.1%。土壤呼吸强度在封禁5 a后增大明显,且随着年限增加逐渐上升,阳坡25 a时达到最大值,而阴坡15 a时达到最大值,随后开始有所下降,25 a后降至最低点,但仍显著高于放牧地,相同封禁年限的土壤呼吸强度阴坡明显高于阳坡。qCO2随着封禁进程逐渐降低,25 a后达到最低值。相关性分析显示微生物生物量碳、氮、磷、呼吸强度、qCO2与土壤养分和恢复年限相关性密切,达到显著(p<0.05)或极显著水平(p<0.01)。     

Bee pollen and propolis as dietary supplements for rabbit: Effect on reproductive performance of does and on immunological response of does and their offspring

To evaluate the effect of bee pollen (BP) and/or propolis (Pro) supplementation on rabbit does, 64 nulliparous NZW rabbits does were distributed among eight groups (eight animals/group). One unsupplemented group was the control; the other seven groups were supplemented, respectively, with zinc bacitracin (ZnB) at 100 mg, BP at 150 and 300 mg, Pro at 150 and 300 mg, BP+Pro at 150 and 300 mg of each three times/week, day after day continuously along eight parities. The BP300, Pro300 and BP+Pro150 groups had higher body weight of litter at birth and number of kids born alive. The BP supplementation at 150 mg increased plasma total protein and albumin than the control group. The BP or Pro at 150 mg decreased plasma T₃ than the other groups except for BP+Pro150. The ZnB group had significantly greater T₃/T₄ ratio compared to BP, Pro and BP+Pro at 150 mg. The BP+Pro150 group had less ALT than the control; BP300 and Pro 300 mg resulted in lower plasma AST than the groups Pro150 with or without BP and the control group. The plasma alkaline phosphatase of BP at 150 or 300 mg and BP+Pro150 was significantly greater than that of the Pro150 group. The BP+Pro300 group had higher WBCs than the other groups. In contrast, the lymphocytes were greater in the Pro and BP+Pro300 groups than in BP, Pro and BP+Pro at 150 mg. The groups supplemented with BP and BP+Pro at 150 and 300 mg had significantly greater SRBCs of doe rabbits and their offspring compared to the control and the ZnB group. The BP at 300 mg increased the serum albumin and α₁‐globulin than the control group. The Pro300 group had greater serum α₂‐globulin and β‐globulin than the control group. The total globulin was significantly greater for the 300 mg propolis‐supplemented groups than the control.     

猕猴桃低乙烯气调库的性能和贮藏效果

介绍了猕猴桃低乙烯气调库。测定了库体的性能,研究了贮藏方式对猕猴桃贮藏性状的影响。结果表明：库体密封性能达良好级,乙烯浓度脱至０．０２μＬ／Ｌ以下;低乙烯气调可延缓果实后熟软化。在两年１８００００ｋｇ果实商业贮藏中,果实贮期可达１８０天以上,果肉硬度为６．８ｋｇ／ｃｍ^２,好果率大于９８％,货架期大于１５天。低乙烯气调是猕猴桃的最佳贮藏方式