氮素胁迫条件下茶树根系发育及生长素的响应

以茶树中茶108为材料,利用营养液水培试验研究3个氮浓度(0 mmol/L,0.2 mmol/L,2.5 mmol/L)条件下茶树的生长表型、生物量、全氮含量、根系发育、生长素类吲哚-3-乙酸(IAA)浓度及相关基因的表达。结果表明,与正常供氮(2.5 mmol/L)相比,低氮(0.2 mmol/L)胁迫条件下茶苗根系干物质量增加,根和叶片全氮含量显著降低,平均不定根伸长,侧根密度显著降低,根、根茎结合处和叶片IAA含量显著增加;缺氮(0 mmol/L)胁迫条件下茶苗叶片和根系干物质量减少,根、茎和叶的全氮含量显著减少,侧根密度显著降低,根、根茎结合处和叶片IAA含量显著增加。qRT-PCR结果表明,低氮(0.2 mmol/L)胁迫条件下茶苗叶片生长素合成基因CsTSB、CsCYP83B1、CsNIT2和根系生长素运输基因CsLAX1、CsPILS3相对表达量显著上调,缺氮(0 mmol/L)胁迫条件下茶苗叶片生长素合成基因CsCYP83B1、CsNIT2和根系生长素运输基因CsLAX1、CsPILS3相对表达量显著上调。由此推测,低氮和缺氮胁迫下叶片生长素合成以及向根系极性运输增加是茶苗根系对氮素胁迫响应的生理机制之一。

Characterization of eating quality and starch properties of two Wx alleles japonica rice cultivars under different nitrogen treatments

To understand the effect of nitrogen(N) fertilizer on rice(Oryza sativa L.) eating and cooking quality(ECQ). Here, we investigated the ECQ attributes, physicochemical foundation of ECQ, and amylopectin fine structure of two Waxy(Wx) alleles japonica rice cultivars Nanjing 9108(NJ9108) and Huaidao 5(HD5) under four N rates(0, 150, 300, and 450 kg ha^-1). Sensory and pasting properties of the two cultivars varied depending on N rates. Compared with the control(0 kg ha^-1), the overall eating quality and sensory value were significantly decreased under the N rates of 300 and 450 kg ha^-1. Further, conventional descriptive analysis showed that the stickiness and retrogradation of cooked rice were significantly decreased. These results indicated that application of N fertilizer seems to affect the texture of cooked rice, causing it to be less sticky, lowering its retrogradation, and consequently reducing its palatability. Results from rapid visco analyzer(RVA) revealed that the peak and breakdown viscosities significantly decreased, while the setback viscosity and peak time increased under the N rates of 300 and 450 kg ha^-1. However, no significant difference was observed when the N rate was 150 kg ha^-1, indicating that less N fertilization can maintain rice ECQ. As the N rate increasing, protein content increased, whereas apparent amylose content, starch content, and gel consistency almost unchanged. Interestingly, compared with the control, under N treatments, the percentage of short amylopectin branches in NJ9108 was decreased, but increased in HD5, as controlled by amylopectin synthesis-related genes. Notably, SSI and BEIIb were down-regulated in NJ9108, whereas BEIIb was up-regulated in HD5. Thus, the palatability of both rice cultivars was significantly decreased under excessive N fertilization as a consequence of reduced stickiness and retrogradation of the cooked rice, which might have resulted from an elevated protein content and altered amylopectin fine structure. In addition, amylopectin synthesis appeared to be affected by N fertilizer and the genotype of the rice cultivar.

光山县长林系列油茶良种茶籽脂肪含量和脂肪酸组成分析

从河南省林木品种审定委员会认定的适宜在本地区推广的长林系列品种中选出具有代表性的主栽油茶品种长林18号、40号、53号和配栽油茶品种长林166号,采用气相色谱-质谱法(GC-MS)对4个油茶品种茶籽仁中脂肪酸组成和含量进行分析,检验了其干籽出仁率和脂肪含量,并对脂肪含量及脂肪酸组分进行了相关性分析。结果表明:3个主栽品种与1个配栽品种干籽出仁率的差异达到了显著水平(p<0.05),但不同品种茶籽脂肪含量差异不大;共检测到了17种脂肪酸组分,其中,茶籽仁中常量组分顺-油酸的含量26.25%~30.82%、棕榈酸的含量2.86%~3.22%、亚油酸的含量3.25%~3.86%。长林40号茶籽中饱和脂肪酸、单不饱和脂肪酸、多不饱和脂肪酸比值为1:6.08:1.05,最接近国际营养学家提出油脂中三类脂肪酸的最佳供能比1:6:1。相关性分析显示,脂肪含量与棕榈酸有一定的相关性,相关系数达到了0.64。结合河南省林木品种审定委员会的研究结论可得,长林40号油茶良种不仅产量高、抗性强,而且干籽出仁率高、含油量高,茶籽脂肪酸组成合理,综合性状优于其他三个品种。

“青春扶贫,走稳2020”主题茶艺创编解析

茶艺是茶文化的重要组成部分,也是茶文化的一种具象表现形式。本茶艺创编以名优绿茶—信阳毛尖为茶品,以“大学生进茶乡做村官,利用自身知识技能,带领山区农民脱贫致富”为主题,用一杯茶回忆大学生3年村官生活的点滴。展现当代大学生响应国家号召,将个人理想与国家发展需求相结合,投身农村扶贫改革的奉献精神,对弘扬社会新风尚、鼓励更多青年积极投入国家发展战略具有重要意义。本文从创作背景与主题的确立、茶艺要素的选择与设计、茶艺流程、茶艺编排与意境营造等方面进行解析,以期为创新茶艺的设计提供借鉴与参考。

活性炭脱色—比色法测定茶叶硝态氮

茶叶中含有大量的多酚类化合物、色素和抗坏血酸等物质,在采用水杨酸比色法测定茶叶硝态氮时发现,茶叶前处理滤液的颜色较深,存在色素干扰。本研究通过加入粉末活性炭对样品滤液进行脱色,比较木质(AC1)和椰壳(AC2)两种材质活性炭对滤液色素的去除效果和硝态氮回收率的影响。结果表明,样品滤液脱色所需活性炭AC1和AC2的量分别为1%和1‰。对系列硝态氮浓度(0、2.5、5、10、15、20、30、40、50和60 mg·L)的标准液分别进行1%AC1和1‰AC2处理,发现1%AC1处理条件下,测试范围内线性较佳(R~2=0.9998),硝态氮回收率为96.61%~115.04%;而1‰AC2处理下的线性较差(R~2=0.9396),回收率随硝态氮的浓度而改变,在硝态氮浓度为0~5 mg·L时,回收率为0%,10~60 mg·L范围时,回收率随硝态氮浓度的增加由2.24%增加到29.24%。因此,1%AC1脱色可用于比色法测定茶叶硝态氮。

茶学专业英语课程教学探讨——以信阳农林学院为例

英语课程是茶学专业的专业选修课之一。本文从教材和教学2个方面阐述了茶学专业英语课程教学现状,并提出在没有教材的情况下,可以利用国际学术会议学习成果、英文视频、英文歌曲、英文原版著作、国际期刊文献、国外茶叶企业网站等进行课堂教学实践,以期为优化茶学专业英语课程教学方法提供参考。