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苹果套袋生产现状和存在的问题及建议 总被引:1,自引:0,他引:1
综述了国内外苹果套袋生产现状、目前苹果套袋栽培应注意的几个问题及解决方法,提出进一步完善苹果套袋栽培技术体系等建议. 相似文献
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近年来瑞丽育种站为了获得突破性创新亲本,在F1(栽培原种×栽培原种,或栽培原种×野生种)间相互杂交获得对等F2代,再以F2×F2获得对等F3代,按此“对等杂交”方式着力构建独立亲本系统。在云瑞15系列123份创新材料中,有56份对等F2代(A类)、22份对等F1-BC1代(对等F1代与商业种杂交1次,B类)、11份对等F1-BC2代(对等F1代与商业种杂交2次,C类)、23份对等F2-BC1代(对等F2代与商业种杂交1次,D类),以及11份传统高贵化杂交F3代(野生种与传统亲本或品种杂交3次,E类)。本研究通过采用DTOPSIS法对甘蔗株高、茎径、单茎重、有效茎数、蔗产量、锤度、含糖量进行综合评价,结果表明:⑴接近度Cg值最大的10份材料分别是:云瑞15-88(对等F1-BC1,B类)、云瑞15-150(对等F1-BC2,C类)、云瑞15-153(F3,E类)、云瑞15-158(F3,E类)、云瑞15-127(对等F1-BC1,B类)、云瑞15-155(F3,E类)、云瑞15-90(对等F2-BC1,D类)、云瑞15-29(对等F2,A类)、云瑞15-97(F3,E类)、云瑞15-134(对等F1-BC1,B类),E类有4份(最多),占40%;⑵在123份材料中,超过ROC22(CK1)有37份,占30.1%,超过粤糖93-159(CK2)有71份,占57.7%,有52份材料未超过双对照。在超过对照ROC22的37份材料中,F3代(E类)占相应同类材料的比例最大,为45.5%,其次是对等F1-BC2(C类)、对等F1-BC1(B类)、对等F2-BC1(D类),对等F2代材料(A类)最小,为21.4%。在56份对等F2材料(A类)中,野生血缘F1代超过对照ROC22的比例达到50%;⑶从各类材料相对接近度Cg的平均值来看,A类(对等F2代)B类(对等F1-BC1代)>D类(对等F2-BC1代)>C类(对等F1-BC2)>CK(对照)>E类(F3代)。所以,传统高贵化杂交F3代(E类)整体上综合评价最好,按“对等杂交”方式利用甘蔗野生资源具有潜在的优势。 相似文献
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Weixuan Lan Xia Xiao Yongjia Jiang Lijie Jiang Xu Zhao Zhaoyang Yu Biwen Zhu Congcong Li Lin Bian Zhiqiang Wang 《Journal of veterinary pharmacology and therapeutics》2019,42(3):355-360
Pasteurella multocida is the causative agent of fowl cholera, and florfenicol (FF) has potent antibacterial activity against P. multocida and is widely used in the poultry industry. In this study, we established a P. multocida infection model in ducks and studied the pharmacokinetics of FF in serum and lung tissues after oral administration of 30 mg/kg bodyweight. The maximum concentrations reached (Cmax) were lower in infected ducks (13.88 ± 2.70 μg/ml) vs. healthy control animals (17.86 ± 1.57 μg/ml). In contrast, the mean residence time (MRT: 2.35 ± 0.13 vs. 2.27 ± 0.18 hr) and elimination half‐life (T½β: 1.63 ± 0.08 vs. 1.57 ± 0.12 hr) were similar for healthy and diseased animals, respectively. As a result, the area under the concentration curve for 0–12 hr (AUC0–12 hr) for FF in healthy ducks was significantly greater than that in infected ducks (49.47 ± 5.31 vs. 34.52 ± 8.29 μg hr/ml). The pharmacokinetic differences of FF in lung tissues between the two groups correlated with the serum pharmacokinetic differences. The Cmax and AUC0–12 hr values of lung tissue in healthy ducks were higher than those in diseased ducks. The concentration of FF in lung tissues was approximately 1.2‐fold higher than that in serum both in infected and healthy ducks indicating that FF is effective in treating respiratory tract infections in ducks. 相似文献
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Hou J.-J. Li B.-C. Wang J.-C. Yao L.-R. Bian X.-X. Hu N. Si E.-J. Yang K. Meng Y.-X. Ma X.-L. Wang H.-J. 《草地学报》2019,(1):112-122
This study firstly researched germination characteristics of Halogeton glomeratus under different concentrations of heavy metals Cu2+,Zn2+,Ni2+,Cd2+ and Pb2+ supplemented with 100 mmol·L-1 NaCl. The results showed that germination rate and germination potential increased at first and then decreased with the increase of the heavy metals concentrations. It indicated that the low concentration of heavy metal ions promoted the germination of plants. Fresh weight,dry weight and seedlings height decreased gradually. The results of ion contents showed that Cd2+ and Pb2+ contents increased at first and then decreased,and Cu2+,Zn2+ and Ni2+ contents increased with increasing heavy metals concentrations. The root activity of Cu2+ and Zn2+ increased first and then decreased,and it decreased with the increase of Ni2+,Cd2+ and Pb2+ concentrations. The comprehensive clustering and principal component analysis were carried out to obtain the critical concentrations of Cu2+,Zn2+,Ni2+,Cd2+ and Pb2+ in Halogeton glomeratus,which were 1.00 mmol·L-1,10.00 mmol·L-1,0.30 mmol·L-1,0.20 mmol·L-1 and 0.50 mmol·L-1,respectively. The most important indexes were germination index,dry weight,germination energy,dry weight and germination energy when the stress concentration reached the critical value for Halogeton glomeratus. © 2019 Journal of Refrigeration. All rights reserved. 相似文献
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以塔里木大学动物科学学院校园内试验站(地处新疆阿拉尔市,40°54′21′′N,81°30′20″E)为试验点,以4份栽培和4份野生草木樨(Melilotus suaveolens)种质资源为对照,对阿克苏白花草木樨(M.albus)品系的草产量性状和适应性进行了分析和评价。结果表明,阿克苏白花草木樨出苗后64d进入现蕾期,75d进入初花期,生育天数较短;阿克苏白花草木樨的干草产量为5 874.23kg·hm~(-2),较对照增产18.76%~67.20%;株高为125.27cm,鲜干比为4.23,均优于对照,草产量性状较好;叶片保水率为65.00%,越夏率为99.00%,对阿克苏地区高温和干旱的气候条件具有较强的适应性;综合性能排名第一,具有转化为野生栽培品种的潜力。 相似文献
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Optimization and physicochemical properties of nutritional protein isolate from pork liver with ultrasound‐assisted alkaline extraction
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Ye Zou Huan Bian Pengpeng Li Zhilan Sun Chong Sun Muhan Zhang Zhiming Geng Weimin Xu Daoying Wang 《Animal Science Journal》2018,89(2):456-466
The aim of this study was to investigate the optimal conditions of ultrasound‐assisted alkaline extraction (UAAE) on pork liver protein isolate (UPLPI) and its physico‐chemical properties. Response surface methodology was used to determine the optimal conditions for UAAE, which were at ultrasonic power 265 W, ultrasonic time 42 min, NaOH concentration 0.80%, temperature 50°C, and solvent/raw material ratio 70. The extraction yield and efficiency of UPLPI were significantly improved over the conventional alkaline extraction (PLPI). The results of amino acid composition showed that UAAE could increase serine (36.5 g/kg), arginine (38.1 g/kg), alanine (37.5 g/kg), proline (48.7 g/kg), phenylalanine (55.6 g/kg) and lysine (47.2 g/kg) elution amount. The changes in fourier transform infrared spectra indicated unfolding and destruction of the protein structure in UPLPI. The differential scanning calorimetry analysis presented UPLPI with a slightly lower onset and peak denaturation temperature over PLPI. Surface hydrophobicity increased and the microstructures presented larger and more pores of UPLPI, therefore, it had better in vitro digestibility than PLPI. Therefore, UPLPI might have a potential application prospect in the food field due to its changes on molecular structure as well as on the microstructure of protein by UAAE. 相似文献