榛仁中氮、磷、钾、钙与贮藏物质的相关性分析

以杂种榛优良品系为试材,分析氮、磷、钾、钙与贮藏物质的相关性。结果表明:氮、磷、钾和钙与脂肪显著或极显著正相关。氮、磷和钙与蔗糖显著或极显著正相关,‘82-11'品系中的磷和钾与可溶性总糖显著或极显著正相关,‘84-237'品系中的钙与可溶性总糖显著正相关,‘84-402'品系中的磷素与可溶性总糖显著正相关。

草莓主要营养元素的缺素症

本文描述了草莓氮、磷、钾、钙的缺素症。缺氮叶小,叶子由绿转黄,但幼叶随着缺氮加重叶色更绿。缺磷严重时叶片黑色具光泽,下部叶子呈紫色,顶端生长受阻。缺钾特征是老叶的叶片发暗,干枯,灼伤或坏死,幼叶无症状。缺钙特点是叶焦,硬果,生长点受害,叶片皱缩,叶柄会有糖浆状水珠流出。文中还提到了缺素的矫正措施。

Effects of Urea Ammonium Chloride of Different Fertilization Patterns on Maize Yield and Yield Components

[Objective] To understand the application effects of urea ammonium chloride fertilizer on maize production. [Methods] A field plot experiment was conducted to study the effects of urea ammonium chloride of different fertilization patterns on summer maize yield and yield components. [Results] Urea ammonium chloride had a long fertilizer effect and the same yield-increasing effect with urea, which could im- prove the agronomic traits and economic traits of maize apparently and the applica- tion of urea ammonium chloride with nutrient reduction of 40% （namely just use urea ammonium chloride equaled 60% pure nitrogen）, had the same yield-increasing effect with urea of traditional fertilization patterns, and input-output ratio was high and the economic benefit was remarkable. [Conclusion] To provide scientific theoretical direc- tion for large area popularization and application of urea ammonium chloride.

Effect of nitric oxide-induced tyrosine phosphorylation of calcium-activated potassium channel α subunit on vascular hyporesponsiveness in rats

Objective: To study the effect of nitric oxide-induced tyrosine phosphorylation of large-conductance calcium-activated potassium (BK Ca) channel α subunit on vascular hyporesponsiveness in rats. Methods: A total of 46 Wistar rats of either sex, weighing 250 g±20 g, were used in this study. Models of vascular hyporesponsiveness induced by hemorrhagic shock (30 mm Hg for 2 hours) in vivo and by L-arginine in vitro were established respectively. The vascular responsiveness of isolated superior mesenteric arteries to norepinephrine was observed. Tyrosine phosphorylation of BK Ca α subunit was evaluated with methods of immunoprecipitation and Western blotting. Results: In the smooth muscle cells of the superior mesenteric arteries, the expression of BK Ca α subunit tyrosine phosphorylation increased following hemorrhagic shock, and L-arginine could induce BK Ca channel α subunit tyrosine phosphorylation in a time- and dose-dependent manner. L-NAME (Nω-nitro-L-arginine-methyl-ester), a nitric oxide synthetase inhibitor, could partly restore the decreased vasoresponsiveness of the superior mesenteric arteries after hemorrhagic shock in rats. Down-regulating the protein tyrosine phosphorylation with genistein, a widely-used special protein tyrosine kinase inhibitor, could partly improve the decreased vasoresponsiveness of the superior mesenteric arteries induced by L-arginine in vitro, while up-regulating the protein tyrosine phosphorylation with Na3VO4, a protein tyrosine phosphatase inhibitor, could further decrease the nitric oxide-induced vascular hyporesponsiveness, which could be partly ameliorated by 0.1 mmol/L tetrabutylammonium chloride (TEA), a selective BK Ca inhibitor at this concentration. Conclusions: Nitric oxide can induce the tyrosine phosphorylation of BK Ca α subunit, which influences the vascular hyporesponsiveness in hemorrhagic shock rats or induced by L-arginine in vitro.