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971.
杀菌剂种子处理对镰孢菌侵染玉米的影响   总被引:2,自引:1,他引:1  
采用室内培养皿法和室外盆栽两种方法,分析杀菌剂种子处理(嘧菌脂、咯菌腈、精甲霜灵、克菌丹)单独和复合使用对特定镰孢菌种(禾谷镰孢菌F. graminearum、轮枝镰孢菌F. verticillioides和层出镰孢菌F. proliferatum)的影响。盆栽试验方差分析表明,多个性状其菌株效应表现显著,大多性状的互作等变异效应不显著;室内试验的方差分析表明,除了品种×种子处理间的互作效应不显著以外,其余变异来源均表现显著或极显著。两种方法均表明, F. graminearum具有更强的致病力。盆栽试验表明,多数性状的种子处理间没有显著差别,就根长和干重来说,使用咯菌腈处理的效果相对较好。室内结果表明,含有咯菌腈和克菌丹处理的种子均具有较好效果,其中以单独使用咯菌腈效果最好。杀菌剂处理对不同镰孢菌菌株具有不同的影响,所有杀菌剂处理对F. graminearum的效果均差于对F. proliferatum和F. verticillioides的效果。嘧菌脂种子处理的效果最差,单独使用咯菌腈的效果最好。  相似文献   
972.
973.
王帅  陈根元  张玲  胡建军  马春晖 《兽医大学学报》2013,(12):1912-1916,1922
通过检测苦马豆素(swainsonine,SW)抗血清治疗小花棘豆中毒家兔血清免疫和生化指标变化,评价SW抗血清对家兔小花棘豆中毒的治疗效果。将18只家兔随机分为对照组(6只)、攻毒组(6只)和攻毒治疗组(6只),攻毒试验兔按干重拌料饲喂10g/(kg·d)小花棘豆草粉,攻毒组试验兔出现死亡时(第70天)停止攻毒。攻毒第21天,攻毒治疗组试验兔注射SW抗血清,每只兔每天0.5mL,连续注射4d。以攻毒试验开始进行首次采血,试验开始后每7d采血1次,进行血清免疫和生化指标测定。结果显示,攻毒第7天时攻毒家兔血清AKP活性和SW含量显著高于对照家兔(P〈0.05);第14天时攻毒家兔血清AST和LDH活性显著高于对照家兔(P〈0.05),血清AMA活性和E-玫瑰花环率均显著低于对照家兔(P〈0.05);第21天时攻毒家兔血清BUN、CRE和GLU含量显著高于对照家兔(P〈0.05)。攻毒治疗组家免注射SW抗血清后血清AKP、LDH、AST、ALT活性及BuN、CRE、GLU、SW含量较攻毒家兔显著下降,AMA活性和E~玫瑰花环率显著上升。结果表明,SW抗血清可有效治疗家兔小花棘豆中毒。  相似文献   
974.
刘长月  赵莉  倪亦非 《草业科学》2013,30(2):281-286
本研究将当年收获的苜蓿(Medicago sativa)种子储存于4个温度条件下,采用定期剖种的方法,调查苜蓿籽蜂(Bruchophagus roddi)的越冬虫态及其存活情况。结果表明,苜蓿籽蜂主要以3龄幼虫在苜蓿种子内滞育越冬。10月从田间将苜蓿种子收回,储存温度在18.0 ℃、平均湿度为27.2%(10―12月)时,越冬幼虫于当年12月下旬开始化蛹;储存温度在9.9 ℃,平均湿度为40.1%(10月―次年2月)时,越冬幼虫于次年2月下旬开始化蛹。不同温度和不同时间梯度处理苜蓿种子结果表明,在50 ℃、-30 ℃条件下处理1 d,籽蜂幼虫的死亡率均达100%,苜蓿种子的发芽率分别为93.33%和88.33%。  相似文献   
975.
Seeds of Albizia chinensis(Osb.) Merr. in addition to water were also treated with different treatments by incubating in ethyl alcohol, acetone, and petroleum ether at room temperature for different du...  相似文献   
976.
Summary

We utilized the Boise National Forest's Hazard/Risk model, along with fire history records and fire behavior models, to estimate the current and anticipated levels of large wildfires and associated greenhouse gas and particulate emissions based on the forest condition and wildfire regime on the BNF. The model indicated that the forests at greatest risk of large, intense wildfires are the dense pondero-sa pine-Douglas-fir forests that make up over 1.1 million acres on the forest. We conclude that without an aggressive treatment program to reduce large areas of contiguous heavy fuel loadings the forest will be burned at an annual average rate of about 7.5% of the remaining at-risk forest. Using recent fire data to develop average patterns of intensity in wildfires within this forest type, we estimate that emissions will average around 1 million tons of carbon (C) per year over the next 20 years as the bulk of the ponderosa pine forests are burned. An aggressive treatment program featuring the removal of fuels where necessary, and prescribed fire as a means of re-introducing fire to these ecosystems, would result in a 30-50 percent reduction in the average annual wildfire experienced in the dense ponderosa pine forests, a 14-35% decrease in the average annual C emissions, and a 10-31% decrease in particulate emissions. We argue that the most effective way to curb emissions is with an aggressive treatment program linked to a landscape-based ecosystem management plan. This would have the effect of breaking up large contiguous landscape patterns so that fires become more patchy and diverse in their environmental impact, resulting in significantly reduced emissions as well as improved landscape diversity.  相似文献   
977.
2012年7月,南宁市郊某猪场因引进猪不慎而引发了一起以体温升高、呼吸困难、黄疸和贫血为特征的疾病,发病率为50%,病死率为4.2%,死亡率为2.1%;经过临床症状、病理解剖和实验室检查,诊断为猪附红细胞体病,用药治疗7d,除3头危重病猪淘汰外,其余基本治愈,治愈率达97%以上。结果表明,猪附红细胞体病的诊断需要结合临床症状、病理解剖和实验室检查做出综合分析,对猪附红细胞体较敏感的药物为贝尼尔和盐酸多西环素。  相似文献   
978.
分析了废旧手机所蕴含的经济价值,简述了当前废弃手机回收处理的一些方法、工艺技术。重点探讨了废旧手机中金属的回收利用技术,并对未来我国废旧手机的回收和资源化利用提出了一些合理性意见,从而实现资源的综合利用。  相似文献   
979.
High-amylose corn starch (HACS) was treated with high temperature–pressure (HTP) treatment and pullulanase debranching. It was found that 24 h storage was favorable for resistant starch (RS) formation. Structure (granular morphology, fractal structure, lamellar structure, crystalline structure, weight-average molecular weight) and properties (swelling power, solubility, enzymatic resistivity) were evaluated for native starch and the samples with 24 h storage. By modification, the surface became loose and rough fragmented and the birefringence crosses disappeared. All samples displayed a B + V crystalline structure. The scattering objects of native starch at the higher scale level were more compact than those of modified starches, and the latter displayed a mass fractal structure which became more compact as debranching increased. The native starch contained RS2 and RS5, while the modified samples included RS3 and RS5. The higher amount of V-type crystals and the starch chains with smaller molecular weight could lead to form more RS. Interestingly, a surface fractal structure with Ds2 was measured for the modified starches, leading to more RS, since some active sites of starch molecules were masked by the ordered-aggregations of molecular chains in the scattering objects. Furthermore, the more compact scattering objects with Dm1 contributed to forming more RS.  相似文献   
980.
Summary

Studies of herbaceous plants suggest that cold hardiness is a complex, quantitatively inherited trait. Although development of cold hardiness is an integral part of the life cycle of woody perennial plants, studies on the genetic control of cold hardiness in woody perennials are scarce. A better understanding of the genetic control of cold hardiness would be valuable for developing more effective strategies to increase cold hardiness and, hence, climatic adaptation of woody perennial crops. In blueberry, three major dehydrins of 65, 60, and 14 kDa have been found to increase with cold acclimation and decrease with deac-climation. A comparison of these dehydrin levels among various blueberry cultivars and selections has revealed their level of accumulation to be closely associated with cold hardiness level. Efforts are underway to isolate and map the dehydrin genes of blueberry utilizing blueberry populations that segregate for cold hardiness in order to determine if the dehydrin genes map to or co-segregate with QTLs controlling cold hardiness. Progress has been made toward this goal. Cold hardiness levels were determined for a portion of the blueberry mapping populations (derived from testcrosses of Vaccinium darrowi Camp X V. caesariense Mackenz. F1s to another V. darrowi and another V. caesariense) using a laboratory controlled freeze-thaw regime, followed by visual assessment of injury to floral buds. As expected, the V. darrowi and V. caesariense parents were found to differ significantly in terms of cold hardiness levels (LT50s of -13°C and -20°C, respectively). Mean cold hardiness level of F1s (LT50 of -14.7°C) was skewed toward the V. darrowi parents suggesting that cold hardiness is a partially recessive trait. The sequence of a 2.0 kb cDNA clone, which encodes the 60 kDa blueberry dehydrin, was used to map a dehydrin-related gene to current linkage group 12 of the V. caesariense testcross population. A preliminary comparison of the segregation pattern of the dehydrin-related gene to that of the cold hardiness trait suggests that the marker does not segregate with cold hardiness.  相似文献   
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