本研究调查了香味和抗寒无核品种选育中不同浓度的多效唑及胚采集时期对胚形成、萌发和成苗率的影响。结果显示，不同浓度的多效唑对不同葡萄品种子房和胚的发育影响不一致。红无籽露×北冰红和昆香无核×泰山-2组合在1.5 mg L^-1多效唑处理下胚形成率最高。红无籽露×北冰红组合在1.0 μmol L^-1多效唑处理下萌芽率和成苗率最高，但红无籽露×昆香无核组合在0.2 μmol L^-1多效唑处理下萌芽率最好。不同的杂交组合取胚时间也不同。火焰无核×玫瑰香最佳取胚时间为授粉后39 d，昆香无核×北冰红为授粉后46 d，红宝石无核×北冰红及奇妙无核×双优为授粉后41 d。另外，向培养基中补充0.5 mg L^-1吲哚丁酸可以帮助畸形苗恢复为正常幼苗并获得生长健壮的子代。研究结果将为利用胚挽救技术选育无核葡萄新品种奠定基础。

Indoor microclimate is important for crop production and quality in greenhouse cultivation. This paper focuses on microclimate study based on a computational fluid dynamics (CFD) model of a typical plastic greenhouse (with a sector shape vertical cross-section) popularly used in central China. A radiation model is added into the CFD model so as to simulate coupling of convective transfers and radiative exchanges at the cover and the roof, instead of using the usual coupling approach based on energy balance. In addition, a fractal permeability model is innovatively adopted in the modeling of the crop canopy. Compared the numerical results with measured experimental data, the model simulation is proved with success. This model then is used to explore the microclimate variable distributions in the greenhouse. It shows that the airflow pattern, temperature and humidity profiles are different from those in a sawtooth Mediterraneantype greenhouse. The study suggests that this deliberately developed CFD model can be served as a useful tool in macroclimate research and greenhouse design investigating.

Cold stress responses help insects to survive under low temperatures that would be lethal otherwise. This phenomenon might contribute to the invasion of some Bemisia tabaci cryptic species from subtropical areas to temperate regions. However, the molecular mechanisms regulating cold stress responses in whitefly are yet unclear. Mitogen-activated protein kinases (MAPKs) which including p38, ERK, and JNK, are well known for their roles in regulating metabolic responses to cold stress in many insects. In this study, we explored the possible roles of the MAPKs in response to low temperature stresses in the Mediterranean cryptic species (the Q-biotype) of the B. tabaci species complex. First, we cloned the p38 and ERK genes from the whitefly cDNA library. Next, we analyzed the activation of MAPKs during cold stress in the Mediterranean cryptic species by immuno-blotting. After cold stress, the level of phospho-p38 increased but no significant change was observed in the phosphorylation of ERK and JNK, thus suggesting that the p38 might be responsible for the defense response to low temperature stress. Furthermore, we demonstrated that: i) 3 min chilling at 0°C was sufficient for the activation of p38 MAPK pathway in this whitefly; and ii) the amount of phosphorylated p38 increased significantly in the first 20 min of chilling, reversed by 60 min, and then returned to the original level by 120 min. Taken together, our results suggest that the p38 pathway is important during response to low temperature stress in the Mediterranean cryptic species of the B. tabaci species complex.