Abstract

An experiment was conducted in a split plot factorial design with 3 replications for evaluating the physiological responses of cumin (Cuminum cyminum L.) to different times and types of stress modulators under rain-fed and irrigated conditions. The main factors included cultivation method at the 2 levels of rain-fed and irrigated conditions and foliar application times (once in the vegetative phase and twice in the vegetative and flowering stages) and sources of stress modulators at the 4 levels of control, 1.5 M glycine betaine (GB), 10^–7 mM brassinosteroids (BRs), and 1.5 μM sodium nitroprusside (SNP). The rain-fed cultivations included more carotenoids, H₂O₂, proline, GB content, catalase, superoxide dismutase, and guaiacol peroxidase activities and less chlorophyll a, while further chlorophyll b appeared in the irrigated cultivations. The application times had no significant effects on the plant’s physiological attributes. Both in the rain-fed and irrigated conditions, foliar applications of BRs increased the activities of enzymatic or non-enzymatic antioxidants in cumin as compared to the other osmotic modulators. Under the rain-fed conditions, spraying of BRs increased the contents of chlorophyll a, chlorophyll b, carotenoids, and proline and catalase, superoxide dismutase, and guaiacol peroxidase activities compared to the control, while decreasing H₂O₂ and glycine betaine contents. Under the irrigated conditions, the amounts of chlorophyll a, chlorophyll b, carotenoids, proline, and GB and catalase, superoxide dismutase, and guaiacol peroxidase activities enhanced, whereas H₂O₂ content were lowered in comparison to the control. Overall, the applied modulators could be classified as brasinosteroids > glycine betaine > sodium nitroprusside in terms of reducing drought stress impacts through their modulatory effects of enhancing enzymatic antioxidant activities.

中文翻译：

---

雨水和灌溉条件下小茴香对时间和压力调节剂类型的生理响应

摘要

在有3个重复的分解图因子分解设计中进行了一项实验，以评估在雨水和灌溉条件下小茴香（Cuminum cyminum L.）对不同时间和类型的压力调节剂的生理反应。主要因素包括在雨水和灌溉条件下2个水平的栽培方法和叶面施用时间（在营养阶段一次，在营养和开花阶段两次）和在4个控制水平上的压力调节剂来源1.5 M甘氨酸甜菜碱（GB），10 ^–7 mM油菜素类固醇（BRs）和1.5μM硝普钠（SNP）。雨养栽培中含有更多的类胡萝卜素H ₂ O ₂，脯氨酸，GB含量，过氧化氢酶，超氧化物歧化酶，和愈创木酚过氧化物酶活性和更少的叶绿素一个，同时进一步叶绿素b出现在灌溉栽培。施用时间对植物的生理特性没有显着影响。与其他渗透调节剂相比，在雨养和灌溉条件下，BR的叶面施用均可提高孜然中酶促或非酶促抗氧化剂的活性。在雨养条件下，与对照相比，喷洒BR可以增加叶绿素a，叶绿素b，类胡萝卜素，脯氨酸和过氧化氢酶，超氧化物歧化酶和愈创木酚过氧化物酶的含量，同时降低H ₂ O₂，甘氨酸甜菜碱含量。在灌溉条件下，叶绿素a，叶绿素b，类胡萝卜素，脯氨酸和GB的含量以及过氧化氢酶，超氧化物歧化酶和愈创木酚过氧化物酶的活性均增加，而H ₂ O ₂含量则比对照降低。总体而言，就其通过增强酶抗氧化活性的调节作用来减少干旱胁迫影响而言，所应用的调节剂可分类为油菜素类固醇>甘氨酸甜菜碱>硝普钠。