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排序方式: 共有838条查询结果,搜索用时 109 毫秒
831.
利用豫816等8个玉米骨干自交系为材料,对授粉与未授粉处理自交系导致玉米衰老表型症状和叶片叶绿素含量变化以及衰老相关基因表达比较分析。结果表明,阻止授粉植株叶片与授粉对照相比,豫816和B73自交系表现出衰老提前启动的显著症状,启动衰老提前了17 d,说明阻止授粉对衰老启动具有明显诱导作用;郑58等6个自交系的阻止授粉与授粉对照植株叶片均为绿色,没有衰老症状的出现,说明阻止授粉不具有诱导衰老的作用。诱导衰老植株不同子粒结实率与启动衰老提前的天数密切相关,结实率为0~15%的未授粉植株具有启动衰老提早的诱导作用,结实率达到35%以上的植株则不具有启动衰老提早的诱导作用。6个玉米衰老相关基因差异表达的趋势与衰老表型症状变化趋势基本一致,存在1个基因差异表达与表型衰老症状呈现的时间窗口,可能参与了诱导玉米衰老的启动。 相似文献
832.
Yun Kang Amaia Seminario Michael Udvardi Paolo Annicchiarico 《Journal of Agronomy and Crop Science》2023,209(1):132-143
The adaptation of alfalfa to moisture-favourable and drought-prone environments and its underlying mechanisms have not been thoroughly investigated despite their crucial importance to maximize the crop breeding progress. The main aim of this study was to support breeding strategies by exploring the relationship of leaf morphophysiological traits assessed in three growth chamber experiments with the adaptive response of five cultivars (Mamuntanas; Demnat 203; Erfoud 1; Prosementi; SARDI 10) that showed large genotype × environment interaction (GEI) across 10 drought-prone to moisture-favourable Mediterranean environments. Changes in shoot and root metabolite profiles across moisture-contrasting conditions were assessed for two cultivars with contrasting adaptation pattern. The cultivar specifically adapted to drought-prone environments (Mamuntanas), compared with that specifically adapted to moisture-favourable environments (Demnat 203), displayed: (i) lower leaf wilting under drought stress; (ii) delayed leaf senescence under stress, assessed as limited chlorophyll reduction either in vivo from upper to central leaves or in vitro from control to polyethylene glycol-treated leaflets, (iii) greater leaf tolerance to desiccation, measured in vitro as less pronounced reduction of leaf dry weight from control to polyethylene glycol-treated leaflets, (iv) smaller leaves, (v) lower early root and shoot growth and (vi) lower leaf stomata density. The other cultivars exhibited different combinations and/or intermediate values of these traits. The metabolite profiles of Mamuntanas and Demnat 203 differed more in shoots than in roots. Mamuntanas accumulated more amino acids than Demnat 203 under moisture-favourable and drought conditions. The distinct and partly incompatible combination of traits featuring the cultivars that maximized the crop yield in favourable or drought-prone conditions (Mamuntanas and Demnat 203) improves our understanding of traits contributing to large GEI across moisture-contrasting environments and support the breeding for specific adaptation to either condition. We identified a few inexpensive morphophysiological traits that could be used for early selection targeting drought-prone environments. 相似文献
833.
为了解小麦叶片衰老与缺氮诱导及碳氮平衡之间的关系,以两个缺氮衰老响应敏感品种(周麦24和运旱618)和两个缺氮衰老响应不敏感小麦品种(衡观35和西农979)为材料,分析了小麦苗期低氮诱导下表征叶片衰老的叶绿素含量、F_v/F_m、净光合速率,以及表征碳氮平衡的全氮和非结构性碳水化合物(可溶性糖、淀粉)比值。结果表明,低氮胁迫后,4个小麦品种叶片的净光合速率、叶绿素含量和F_v/F_m显著降低,说明低氮诱导和加速了小麦叶片的衰老,而缺氮衰老响应敏感品种的衰老程度显著高于不敏感品种。缺氮衰老响应敏感和不敏感小麦品种叶片氮含量在低氮胁迫后均显著降低,同时碳累积量(可溶性糖和淀粉含量)均显著升高。进一步分析表明,缺氮诱导的小麦叶片衰老可能并非受独立的氮缺乏和碳累积调控,而可能与碳氮平衡(碳氮比例)有关,即碳氮平衡可能参与了低氮诱导的叶片衰老调控,而缺氮下耐衰老品种的叶片维持碳氮代谢平衡的能力较强。 相似文献
834.
为给耐热性小麦品种的选育和推广提供依据,以黄淮北片小麦全身落黄型品种邯6172和邯麦13及灰白落黄型品种石4185和早衰落黄型品种鲁麦14为供试材料,研究了灌浆期热胁迫对小麦植株含水量、干物质转运量和籽粒灌浆特性的影响,并通过千粒重热感指数评价了不同类型品种的耐热性。结果表明,高温加快了小麦叶片黄化衰老,不同品种衰老快慢不同,邯6172和邯麦13的旗叶、倒2叶、倒3叶分别于热胁迫后19、16、10d开始黄化,叶片黄化速度慢,分别比鲁麦14、石4185晚3~6d。热胁迫使穗、茎、叶含水量下降,不同品种下降速率不同,灌浆后期差异更为显著,其中花后31d鲁麦14、石4185、邯6172和邯麦13穗部含水量分别比对照下降28.7%、30.3%、12.1%和17.4%,叶片含水量分别下降53.8%、44.4%、18.7%和21.5%;鲁麦14、石4185茎秆含水量始终低于邯6172和邯麦13,失水失绿早。热胁迫下全身落黄小麦叶片衰老速度慢,绿叶数目、绿叶面积均较高,穗茎叶含水量相对较高,充分延缓了叶片等光合器官的衰老,保证了正常的生理代谢功能,营养器官干物质转运量和籽粒灌浆速率下降幅度较小,千粒重降低不明显,产量和千粒重热感指数小于1,耐热性好。 相似文献
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837.
838.
The use of widely targeted metabolite profiling to reveal the senescence changes in postharvest ‘Red Globe’ (Vitis vinifera) grape berries 下载免费PDF全文
XU Teng-fei YANG Xin ZHANG Meng GUO Shui-huan FU Wen-jing ZHOU Bi-jiang LIU Yu-jia MA Hai-jun FANG Yu-lin YANG Gang MENG Jiang-fei 《农业科学学报》2022,21(4):1028-1043
Changes in the metabolites of table grapes (Vitis vinifera) reportedly occur during postharvest senescence. The aim of this study was to determine the metabolomic differences in postharvest table grapes (‘Red Globe’) after being subjected to different senescence periods. To this end, we used widely targeted metabolomics based on ultra-performance liquid chromatography and tandem mass spectrometry. A total of 135 differential metabolites were identified. During postharvest senescence, the levels of most differential flavonoids (e.g., pelargonidin 3-O-glucoside, quercetin-3-O-glucoside, and cyanidin 3-O-glucoside) and L-aspartic acid decreased, while the levels of phenolic acids (e.g., trans-4-hydroxycinnamic acid methyl ester) and pantothenol increased. During early and late senescence, the levels of most differential lipids, especially LysoPC, as well as those of nucleotides and their derivatives, such as uridine, decreased and increased, respectively. Collectively, the findings of this study provide fundamental insights into the reasonable control of table grape fruit postharvest senescence and lay a solid foundation for further research. 相似文献