State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining, Qinghai, China.
College of Ecol-Environmental Engineering, Qinghai University, Xining, Qinghai, China.
PeerJ. 2022 Sep 29;10:e14100. doi: 10.7717/peerj.14100. eCollection 2022.
The -pinene is the main allelochemical of many weeds that inhibit the growth of , an important forage and ecological restoration herbage. However, the response changes of -pinene-induced allelopathy to is still unclear. Here, we investigated the physiological, biochemical and phytohormone changes of exposed to different -pinene concentrations. The -pinene-stress had no significant effect on height and fresh weight (FW) of seedlings. The water-soluble proteins, the soluble sugars and proline (Pro) strengthened seedlings immunity at 5 and 10 µL L -pinene. Superoxide dismutase (SOD) and ascorbate peroxidase (APX) increased at 5 µL L -pinene to resist stress. APX reduced the membrane lipid peroxidation quickly at 10 µL L -pinene. The high-activity of peroxidase (POD), APX along with the high level of GSH contributed to the cellular redox equilibrium at 15 µL L -pinene. The POD, glutathione reductase (GR) activity and glutathione (GSH) level remained stable at 20 µL L -pinene. The changes in antioxidant enzymes and antioxidants indicated that was effective in counteracting the harmful effects generated by hydrogen peroxide (HO). The -pinene caused severe phytotoxic effects in seedlings at 15 and 20 µL L. Endogenous signal nitric oxide (NO) and cell membrane damage product Pro accumulated in leaves of seedlings at 15 and 20 µL L -pinene, while lipid peroxidation product malondialdehyde (MDA) accumulated. The chlorophylls (Chls), chlorophyll a (Chl a), chlorophyll b (Chl b) content decreased, and biomass of seedlings was severely inhibited at 20 µL L -pinene. The -pinene caused phytotoxic effects on seedlings mainly through breaking the balance of the membrane system rather than with reactive oxygen species (ROS) productionat 15 and 20 µL L -pinene. Additionally, phytohormone levels were altered by -pinene-stress. Abscisic acid (ABA) and indole acetic acid (IAA) of seedlings were sensitive to -pinene. As for the degree of -pinene stress, salicylic acid (SA) and jasmonic acid (JA) played an important role in resisting allelopathic effects at 15 µL L -pinene. The ABA, Zeatin, SA, gibberellin 7 (GA7), JA and IAA levels increased at 20 µL L -pinene. The -pinene had a greatest impact on ABA and IAA levels. Collectively, our results suggest that seedlings were effective in counteracting the harmful effects at 5 and 10 µL L -pinene, and they were severely stressed at 15 and 20 µL L -pinene. Our findings provided references for understanding the allelopathic mechanism about allelochemicals to plants.
β-蒎烯是许多杂草的主要化感物质，它会抑制 ，这是一种重要的饲料和生态恢复草料的生长。然而，β-蒎烯诱导的化感作用对 的响应变化仍不清楚。在这里，我们研究了不同浓度β-蒎烯处理下 幼苗的生理、生化和植物激素变化。β-蒎烯胁迫对幼苗的高度和鲜重（FW）没有显著影响。在 5 和 10 μL L -1 β-蒎烯下，水溶性蛋白质、可溶性糖和脯氨酸（Pro）增强了幼苗的免疫力。超氧化物歧化酶（SOD）和抗坏血酸过氧化物酶（APX）在 5 μL L -1 β-蒎烯下增加以抵抗应激。APX 在 10 μL L -1 β-蒎烯下迅速降低膜脂质过氧化作用。高活性过氧化物酶（POD）、APX 以及高谷胱甘肽（GSH）水平有助于 15 μL L -1 β-蒎烯时的细胞氧化还原平衡。在 20 μL L -1 β-蒎烯时，POD、谷胱甘肽还原酶（GR）活性和谷胱甘肽（GSH）水平保持稳定。抗氧化酶和抗氧化剂的变化表明，在 15 和 20 μL L -1 β-蒎烯时， 有效地抵抗了由过氧化氢（HO）产生的有害影响。在 15 和 20 μL L -1 β-蒎烯时，β-蒎烯对 幼苗造成严重的植物毒性效应。内源信号一氧化氮（NO）和细胞膜损伤产物 Pro 在 15 和 20 μL L -1 β-蒎烯的 叶片中积累，而丙二醛（MDA）等脂质过氧化产物积累。叶绿素（Chls）、叶绿素 a（Chl a）、叶绿素 b（Chl b）含量降低，20 μL L -1 β-蒎烯严重抑制了幼苗的生物量。β-蒎烯对 幼苗的植物毒性作用主要是通过打破膜系统的平衡而不是通过产生活性氧（ROS）来实现的在 15 和 20 μL L -1 β-蒎烯时。此外，植物激素水平也受到β-蒎烯胁迫的影响。脱落酸（ABA）和吲哚乙酸（IAA）对 幼苗对β-蒎烯敏感。就β-蒎烯胁迫程度而言，水杨酸（SA）和茉莉酸（JA）在 15 μL L -1 β-蒎烯时在抵抗化感作用中发挥重要作用。在 20 μL L -1 β-蒎烯时，ABA、玉米素、SA、赤霉素 7（GA7）、JA 和 IAA 水平增加。β-蒎烯对 ABA 和 IAA 水平的影响最大。总的来说，我们的结果表明，在 5 和 10 μL L -1 β-蒎烯时， 幼苗有效地抵抗了有害影响，而在 15 和 20 μL L -1 β-蒎烯时则受到严重胁迫。我们的发现为理解化感物质对植物的化感机制提供了参考。
