山葡萄砧木对‘黑比诺’葡萄耐旱寒的影响研究

以‘黑比诺’自嫁苗和山葡萄为砧木的嫁接苗为试材,在自然低温胁迫和干旱胁迫条件下,对接穗叶片相对含水量、相对电导率、丙二醛含量、可溶性蛋白和可溶性糖等指标进行了对比。结果表明,干旱胁迫下,与自接苗相比,嫁接苗的叶片相对电导率降低,相对含水量和丙二醛升高;在低温胁迫下,山葡萄嫁接苗的相对电导率降低,丙二醛、可溶性总糖和可溶性蛋白含量均升高。试验初步证明以山葡萄为砧木可提高‘黑比诺’的耐旱性和耐寒性

露地越冬葡萄枝条水分含量与抗旱寒性关系研究

在露地越冬的条件下,以抗寒性较强的几个种间杂交葡萄品种枝条为试材,通过研究不同时期枝条总含水量、自由水、束缚水和枝条萌芽率的变化,分析葡萄枝条水分含量与萌芽率的关系,确定品种抗旱寒性能,并根据水分与萌芽率的隶属分析确定水分含量临界值。结果表明:葡萄枝条抗旱寒性与水分含量各指标均具有相关性,其中与枝条总含水量、束缚水含量显著正相关,与失水量显著负相关,相关系数均达0.896以上。露地越冬期间,枝条总含水量及束缚水含量越高,失水量越小,葡萄失水死亡的几率就越小,枝条萌芽率越高,抗旱寒性越好。‘北红’‘新北醇’‘北玫’‘北玺’‘北馨’等5个品种在宁夏产区2018年冬季至2019年春季的气候条件下可以露地安全越冬,具有较强的抗旱寒性能,而‘威代尔’在露地不能安全越冬,应采取防护措施。研究还发现,冬季枝条含水量和抗旱寒性能还与树龄有关

葡萄多种群种间杂种后代抗病性特征研究

本研究以含山葡萄血统的欧山杂种与含有河岸葡萄、美洲葡萄、欧亚种葡萄血统的杂种后代进行杂交获得的多种群杂交群体后代16个典型株系为材料,以‘北玫’‘北红’‘威代尔’‘贵人香’为对照;通过田间自然鉴定法和室内接种鉴定法,鉴定了露地越冬葡萄多种群种间杂种后代对霜霉病和白粉病的抗性。结果表明:杂种优系表现出明显的抗病优势。田间调查发现,有15个优系对霜霉病表现高抗和抗性,12个优系对白粉病表现免疫和高抗。在室内条件下接种霜霉病后,有11个优系为高抗或抗性级别,明显优于对照品种。因此认为,利用含美洲血统的葡萄基因可选育抗病性能强的新优品种,本试验中的优系‘5-1-247’和‘5-1-444’表现抗病性极好,明显优于其他优系

Prediction of Energy Resolution in the JUNO Experiment

International audienceThis paper presents the energy resolution study in the JUNO experiment, incorporating the latest knowledge acquired during the detector construction phase. The determination of neutrino mass ordering in JUNO requires an exceptional energy resolution better than 3% at 1 MeV. To achieve this ambitious goal, significant efforts have been undertaken in the design and production of the key components of the JUNO detector. Various factors affecting the detection of inverse beta decay signals have an impact on the energy resolution, extending beyond the statistical fluctuations of the detected number of photons, such as the properties of liquid scintillator, performance of photomultiplier tubes, and the energy reconstruction algorithm. To account for these effects, a full JUNO simulation and reconstruction approach is employed. This enables the modeling of all relevant effects and the evaluation of associated inputs to accurately estimate the energy resolution. The study reveals an energy resolution of 2.95% at 1 MeV. Furthermore, the study assesses the contribution of major effects to the overall energy resolution budget. This analysis serves as a reference for interpreting future measurements of energy resolution during JUNO data taking. Moreover, it provides a guideline in comprehending the energy resolution characteristics of liquid scintillator-based detectors

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel