Kaur Gurpreet, Jhanji Shalini
Department of Botany, Punjab Agricultural University, Ludhiana, India.
Department of Floriculture and Landscaping, Punjab Agricultural University, Ludhiana, India.
Plant Physiol Biochem. 2023 Mar;196:1098-1110. doi: 10.1016/j.plaphy.2023.02.044. Epub 2023 Mar 4.
The marketability of cut flowers is determined by their postharvest quality parameters. Among these parameters, vase life is most crucial and different plant growth regulators (PGRs) play a significant role in regulating vase life. With the objective, to regulate vase life and other quality parameters of commercially important cut stems of chrysanthemum cv. White Star, a study was planned to have an insight into the role of different PGRs in orchestrating underlying physio-biochemical and anatomical responses. Three PGRs viz., Benzyl adenine (50, 100, 150 and 200 μM BA), Thidiazuron (5, 10, 15 and 20 μM TDZ) and Salicylic acid (50, 100, 150 and 200 μM SA) were used as pulsing solution. The results revealed that PGR especially 10 μM TDZ delayed leaf and floret senescence as compared to control. The visual observations (retention of green colour of leaves and white of florets) were correlated to enhanced water absorption, relative water content, membrane stability index, total soluble sugars and total soluble proteins ; higher content of chlorophyll in leaves and lower content of carotenoids and anthocyanins in florets. Further, the antioxidant enzymes (peroxidase and catalase) activities were also higher in PGR-treated stems than in control. These results were further supported by anatomical studies that indicated minimum blockage in xylem and maintenance in turgidity of cells as revealed through the size of tissues (radius of pith) of treated stems (control-118.48 mm and 10 μM TDZ-177.94 mm). Although all PGR concentrations significantly maintained relative water content, membrane stability index, respiratory substrates and antioxidant activity for a longer time, the low concentrations of TDZ had the most relevant impact on longevity. The longevity of stems treated with10 μM TDZ was up to 23 days as compared to 13 days in control. So 10 μM TDZ could be used as a chemical tool to improve chrysanthemum longevity and increase its commercial potential.
切花的市场适销性取决于其采后质量参数。在这些参数中，瓶插寿命最为关键，不同的植物生长调节剂（PGR）在调节瓶插寿命方面发挥着重要作用。为了调节商业上重要的菊花品种白星切茎的瓶插寿命和其他质量参数，计划开展一项研究，以深入了解不同PGR在协调潜在的生理生化和解剖学反应中的作用。使用了三种PGR，即苄基腺嘌呤（50、100、150和200μM BA）、噻苯隆（5、10、15和20μM TDZ）和水杨酸（50、100、150和200μM SA）作为脉冲溶液。结果表明，与对照相比，PGR尤其是10μM TDZ延迟了叶片和小花的衰老。视觉观察（叶片绿色和小花白色的保持）与增强的水分吸收、相对含水量、膜稳定性指数、总可溶性糖和总可溶性蛋白相关；叶片中叶绿素含量较高，小花中类胡萝卜素和花青素含量较低。此外，PGR处理的茎中抗氧化酶（过氧化物酶和过氧化氢酶）的活性也高于对照。解剖学研究进一步支持了这些结果，该研究表明，通过处理茎的组织大小（髓半径）显示，木质部堵塞最小，细胞膨压维持良好（对照-118.48mm，10μM TDZ-177.94mm）。虽然所有PGR浓度都能在较长时间内显著维持相对含水量、膜稳定性指数、呼吸底物和抗氧化活性，但低浓度的TDZ对寿命的影响最为显著。用10μM TDZ处理的茎的寿命长达23天，而对照为13天。因此，10μM TDZ可作为一种化学工具来提高菊花的寿命并增加其商业潜力。
