摘要
为明确我国北方不同抗寒性甘蓝型冬油菜响应冷冻胁迫后的生理差异,以强抗寒甘蓝型冬油菜品系2016TS(G)10 和弱抗寒品种天油 2288 为材料进行低温处理,通过观察植株形态、叶片显微结构和超微结构,测定叶片相对电导率(REL),丙二醛(MDA)、可溶性蛋白(SP)、可溶性糖(SS)、脯氨酸(Pro)含量,净光合速率(Pn)、胞间二氧化碳浓度(Ci)、叶绿素含量等指标.研究结果表明:2016TS(G)10 和天油 2288 在-2℃的冷冻胁迫下植株表型和存活率差异最显著.在-2℃持续胁迫 24h的过程中,2 个材料的REL,MDA、SP、SS、Pro含量,Pn、Ci,叶绿素a、叶绿素b含量及叶绿素a/b生理指标变化趋势基本一致,但强抗寒品系 2016TS(G)10 叶片中的SP、SS含量较弱抗寒品种天油 2288 分别增加了 5.10％和 29.69％(P≤0.01),REL和MDA含量分别下降了 4.8％和 17.9％(P≤0.01).在-2℃下,2016TS(G)10 叶片叶绿体结构完整,有较多淀粉粒的积累;而天油 2288 叶片叶绿体破裂、降解,无淀粉粒.室温恢复 48h后,强抗寒的 2016TS(G)10 表型和Pn 恢复能力更强.因此,鉴定北方强冬性甘蓝型冬油菜抗寒性需要在 0℃～-4℃的低温进行,叶片叶绿体结构和数量的稳定,尤其是淀粉粒的积累是影响北方强冬性甘蓝型冬油菜抗寒性的重要因素.
Abstract
In this study,different cold-tolerant Brassica napus L.growing in northern China were treated with freezing to compare their physiological differences.The strong cold-tolerant line 2016TS(G)10 and the weak cold-tolerant variety Tianyou 2288 as the materials were subjected to freezing at-2℃.The plant morphology,leaf micro-structure and ultrastructure were observed,and the relative electrical conductivity(REL),malondialdehyde(MDA),soluble protein(SP),soluble sugar(SS),proline(Pro)content,net photosynthesis rate(Pn),inter-cellular carbon dioxide(Ci),and chlorophyll content were measured.The results showed that the most significant differences in plant morphology and survival rate between the strong cold-tolerant line 2016TS(G)10 and the weak cold-tolerant variety Tianyou 2288 were observed when exposed to-2℃.The physiological indicators of the two ma-terials,including REL,MDA,SP,SS,Pro content,Pn,Ci,chlorophyll a,chlorophyll b content,and chlorophyll a/b,changed in a similar trend,but the SP and SS content of the strong cold-tolerant line 2016TS(G)10 were 5.10％and 29.69％higher than those of in Tianyou 2288(P≤0.01),respectively,and the REL and MDA content were 4.8％and 17.9％lower(P≤0.01).The chloroplast structure of 2016TS(G)10 remained intact,with a more accumulation of starch grains,while the chloroplasts of Tianyou 2288 were broken and degraded,with no presence of starch grains.After being recovered at room temperature for 48 hours,the 2016TS(G)10 exhibited a stronger re-covery in plant morphology and Pn.Therefore,the cold tolerance of northern strong winter rapeseed should be eval-uated under freezing stress ranging from 0℃to-4℃.The stability and number of chloroplasts,especially the accu-mulation of starch granules,is an important factor affecting the cold resistance of winter rapeseed planted in north-ern China.
基金项目
甘肃省科技计划项目(21JR7RA825)
甘肃农业大学科研启动项目(GAU-KYQD-2020-17)
现代农业产业技术体系建设专项(CARS-12)
甘肃省科技重大专项(22ZD6NA009)
甘肃省现代寒旱农业科技支撑项目(KJZC-2023-12)
维普
万方数据