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761.
762.
为了研究水稻联合收割机收获紫云英种子的应用效果,对比分析了机械收种和人工收种两种方法的种子产量、劳动效率、收割成本和经济效益。结果表明,与传统人工收种方法相比,机械收种降低了紫云英种子的损失率,比人工收种产量增加了92.7 kg/hm2,增幅为16.3%;提高了劳动效率,一台收割机一天收获的紫云英种子数量相当于18~20人一天的收种量;节约了紫云英留种生产的劳动成本,提高了紫云英种子生产的经济效益,采用机械收获紫云英种子比人工收种直接降低劳动成本2 175~3 000元/hm2,增加经济收入3 307~4 099元/hm2。该技术的推广应用对缓解南方稻区紫云英种子的短缺问题以及加快紫云英绿肥作物的发展具有重要的作用。 相似文献
763.
764.
Henneguya pagri n. sp. (Myxozoa: Myxosporea) is described from netpen-cultured red sea bream, Pagrus major, in Japan. Affected fish displayed anaemic gills, an enlarged bulbus arteriosus and internal haemorrhaging in the pericardial cavity. Disease outbreaks occurred during the summer and the prevalence of infection reached 75% in August. Plasmodia of H. pagri developed in the bulbus arteriosus of red sea bream, in which degenerative cardiomyopathy was observed. Following maturation of the parasite, the influx of spores into the gills caused congestion of the gill capillaries, resulting in proliferative branchitis. Spores (10.5 x 7.5 microm) were ovoid with two caudal appendages (29.6 microm in average length), with a whip-like extension from the end. Partial small subunit ribosomal RNA gene sequences of H. pagri are closely related to those of H. lateolabracis infecting the bulbus arteriosus of Chinese sea bass, Lateolabrax sp. 相似文献
765.
发酵油茶饼粕饲喂荷斯坦牛的试验研究 总被引:1,自引:0,他引:1
试验采用发酵油茶饼粕代替部分豆粕饲喂泌乳期荷斯坦牛,旨在研究其对奶牛产奶量、乳品质和血液生化指标的影响。试验选取16头泌乳天数相近的荷斯坦牛,采用配对分组设计4个处理组:对照组饲喂基础日粮,试验组分别在基础日粮的精料中,用发酵油茶饼粕分别代替15%、30%和45%的豆粕。试验结果表明,发酵油茶饼粕代替部分豆粕饲喂泌乳期荷斯坦牛,对其产奶量、乳蛋白和乳脂率有一定的提升作用.且发酵油茶饼粕价格相对于豆粕有很大的优势;采用发酵油茶饼粕饲喂荷斯坦牛,能够有效降低饲养成本,值得推广应用。 相似文献
766.
GAO Zhao-li LIU Guang-yi LI Xing HU Zhao YANG Xiang-dong JIANG Bei LI Xian-hua 《园艺学报》2014,30(2):313-317
AIM:To study the protective effect of grape seed proanthocyanidin (GSP) on nephrotoxicity induced by cisplatin (CP) in mice. METHODS:Male C57 mice were randomly divided into 4 groups: control group (N group, n=10), CP group (intraperitoneal injection of CP at dose of 20 mg/kg, n=20), GSP group (intragastric administration of GSP at dose of 500 mg/kg, n=15) and CP+GSP group (intragastric administration of GSP 30 min prior to intraperitoneal injection of CP and intragastric administration of the same dose of GSP 72 h later, n=20). On the 5th day after CP treatment, blood and kidney samples were collected. The renal pathological changes were examined by HE staining. The protein expression of glucose-regulated protein 78 (GRP78) and phosphorylated extracellular signal-regulated kinase (p-ERK) was examined by Western blotting and immunohistochemical staining. RESULTS:Renal index, blood urea nitrogen and serum creatinine were significantly higher in CP group than those in N group. The renal tissues were heavily damaged in CP group. The protein expression of GRP78 and p-ERK increased in CP group compared with N group. GSP treatment alleviated the increase in the renal index, blood urea nitrogen and serum creatinine. The damages of the renal tissues were attenuated. The protein expression of GRP78 and p-ERK was obviously reduced in CP+GSP group compared with CP group. CONCLUSION:GSP prevents kidney from CP-induced damage by suppression of endoplasmic reticulum stress. 相似文献
767.
矮壮素浸种对黄瓜幼苗下胚轴伸长及细胞亚显微结构的影响 总被引:1,自引:0,他引:1
为了明确矮壮素(CCC)浸种对黄瓜幼苗下胚轴伸长的影响,以3 000 mg·L-1 矮壮素对黄瓜品种中农203 进行浸种处理,测定黄瓜幼苗下胚轴生长的形态指标,并采用透射电子显微镜观察下胚轴薄壁细胞亚显微结构的变化。结果表明:矮壮素浸种处理能显著降低黄瓜幼苗下胚轴的长度,促进干物质积累。与对照相比,矮壮素浸种处理使黄瓜幼苗下胚轴薄壁细胞的细胞壁明显加厚,液泡数目增加,体积变小,叶绿体形态和结构发生改变,基粒含量和淀粉粒数量增加。 相似文献
768.
769.
Although many studies have been carried out on plant–animal mutualistic assemblages, the roles of functional traits and taxonomy in determining both whether interactions involve mutualisms or predation and the structure of such assemblages are unclear. We used semi‐natural enclosures to quantitatively assess the interaction strengths between seeds of 8 sympatric tree species and 4 rodent species in a tropical forest in Xishuangbanna, Yunnan, Southwest China. We found 2 clusters of species in the seed–rodent network represented by 2 genera in the Fagaceae (Castanopsis, Lithocarpus). Compared to seeds of 3 Castanopsis species, seeds with heavy weight, hard coat or caloric content (including 3 Lithocarpus species) were eaten less and more frequently hoarded by rodents. In turn, hoarded seeds showed less predation and more mutualism with rodents. Our results suggest that seed traits significantly affected the hoarding behavior of rodents, and, consequently, the occurrence of mutualisms and predation as well as assemblage structure in the plant–animal seed dispersal system. Taxonomically‐related species with similar seed traits as functional groups belong to the same substructures in the assemblage. Our results indicate that both seed traits and taxonomic relationships may simplify thinking about seed dispersal systems by helping to elucidate whether interactions are likely to be dominated by predation or mutualism. 相似文献
770.