本文選題：煙草　切入點(diǎn)：干旱脅迫　出處：《植物營(yíng)養(yǎng)與肥料學(xué)報(bào)》2017年02期

【摘要】：【目的】挖掘植物自身的抗旱能力是提高農(nóng)業(yè)水分利用效率的有效措施。本研究通過(guò)比較水分脅迫處理下5個(gè)烤煙品種苗期根系發(fā)生和伸長(zhǎng)以及葉片光合特性的變化,探討烤煙抗旱能力差異的生理機(jī)制,為煙草生產(chǎn)的可持續(xù)發(fā)展提供理論依據(jù)�！痉椒ā坎捎盟嘣囼�(yàn),設(shè)置對(duì)照和水分脅迫處理(添加2.5%PEG處理來(lái)模擬中度干旱),研究5個(gè)烤煙品種苗期的地上部和根系的生物量、一級(jí)和二級(jí)側(cè)根的發(fā)生和伸長(zhǎng),利用Li-Cor 6400光合測(cè)定系統(tǒng)測(cè)定葉片的光合速率和氣孔導(dǎo)度等參數(shù),利用FLIR手持式紅外熱成像儀測(cè)定新展開葉的葉片溫度,分析煙草抗旱能力差異明顯的生理機(jī)制�！窘Y(jié)果】水分脅迫條件下5個(gè)烤煙品種的生長(zhǎng)差異明顯。與對(duì)照處理相比,水分脅迫對(duì)大平板和農(nóng)大202的生長(zhǎng)影響不明顯,但柳葉尖、金星6007和中煙100的地上部和根系生物量顯著被抑制,降幅范圍在66%~83%,達(dá)到差異極顯著水平。水分脅迫抑制5個(gè)烤煙品種一級(jí)和二級(jí)側(cè)根的伸長(zhǎng),但大平板和農(nóng)大202的一級(jí)側(cè)根數(shù)目和二級(jí)側(cè)根密度顯著增加,最終導(dǎo)致根系生物量沒(méi)有下降;另外3個(gè)煙草品種柳葉尖、金星6007和中煙100的側(cè)根發(fā)生增加趨勢(shì)不明顯。水分脅迫處理下抗旱能力強(qiáng)的大平板和農(nóng)大202地上部生物量和葉片溫度變化不明顯,而葉片的凈光合速率顯著下降,但其降幅顯著低于3個(gè)抗旱能力弱的烤煙品種。與對(duì)照處理相比,抗旱能力弱的柳葉尖、金星6007和中煙100葉片的氣孔導(dǎo)度和蒸騰速率顯著下降,葉片溫度上升5~7℃。進(jìn)一步的研究表明,PEG處理下耐旱能力強(qiáng)烤煙品種側(cè)根數(shù)目的顯著增加是地上部維持較強(qiáng)光合能力的主要原因�！窘Y(jié)論】抗旱能力強(qiáng)的煙草品種苗期受到水分脅迫時(shí)其一級(jí)和二級(jí)側(cè)根顯著增加,進(jìn)而能保持較高的光合特性。
[Abstract]:Objective: to explore the drought resistance of plants is an effective measure to improve the water use efficiency of agriculture.In this study, the physiological mechanism of drought resistance difference of five flue-cured tobacco varieties was studied by comparing the changes of root formation, elongation and photosynthetic characteristics of leaves in seedling stage under water stress.To provide the theoretical basis for the sustainable development of tobacco production. [methods] the biomass of shoot and root of 5 flue-cured tobacco varieties at seedling stage was studied by using water culture experiment and water stress treatment (adding 2.5%PEG treatment to simulate moderate drought).The occurrence and elongation of primary and secondary lateral roots, the photosynthetic rate and stomatal conductance of leaves were measured by Li-Cor 6400 photosynthetic system, and the leaf temperature of newly expanded leaves was measured by FLIR hand-held infrared thermal imager.The physiological mechanism of tobacco drought resistance difference was analyzed. [results] the growth difference of five flue-cured tobacco varieties under water stress was obvious.The effects of water stress on the growth of large flat plate and Nongda 202 were not obvious, but the aboveground and root biomass of willow leaf tip, Jinxing 6007 and Zhongyan 100 were significantly inhibited, and the decrease range was 6683cm, which reached the most significant level.Water stress inhibited the elongation of the first and second lateral roots of five flue-cured tobacco varieties, but the number of the first lateral roots and the density of the secondary lateral roots of the big flat and Nongda 202 increased significantly, resulting in no decrease of root biomass, and the willow tip of the other three tobacco varieties.The increasing trend of lateral roots of Venus 6007 and Zhongyan 100 is not obvious.Under water stress, the aboveground biomass and leaf temperature of big flat and Nongda 202 with strong drought resistance did not change significantly, while the net photosynthetic rate of leaves decreased significantly, but the decrease was significantly lower than that of three flue-cured tobacco varieties with weak drought resistance.Compared with the control, the leaf stomatal conductance and transpiration rate of willow leaf tip, Jinxing 6007 leaf and Zhongyan 100 leaf were significantly decreased, and the leaf temperature increased 5 ~ 7 鈩，

本文編號(hào)：1689898