玉米自交系吐丝期叶片光合参数与其耐旱性的关系

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陈春梅, 高聚林, 苏治军, 于晓芳, 胡树平, 赵晓亮. 玉米自交系吐丝期叶片光合参数与其耐旱性的关系. 作物学报, 2014, 40(9): 1667-1676[CHEN Chun-Mei, GAO Ju-Lin, SU Zhi-Jun, YU Xiao-Fang, HU Shu-Ping, ZHAO Xiao-Liang. Relationship between Leaf Photosynthetic Parameters and Drought Resistance at Silking Stage in Maize Inbred Lines. Acta Agronomica Sinica, 2014, 40(9): 1667-1676] 复制到剪切板

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玉米自交系吐丝期叶片光合参数与其耐旱性的关系

陈春梅, 高聚林^*, 苏治军, 于晓芳, 胡树平, 赵晓亮

内蒙古农业大学农学院, 内蒙古呼和浩特 010019

^*通讯作者(Corresponding author): 高聚林, E-mail:nmgaojulin@163.com

收稿日期:2014-06-16

基金:本研究由内蒙古杰出青年基金项目(2011JQ02), 国家现代农业产业技术体系建设专项(CARS-02-63)和国家粮食丰产科技工程项目(2011BAD16B13, 2012BAD04B04, 2013BAD07B04, 2011BAD16B14)资助;

摘要

从玉米自交系吐丝期光合特性适应干旱环境的角度, 探索玉米自交系的耐旱性。2012年在土默川平原灌区和河套平原灌区以及2013年河套平原灌区, 利用耐旱性不同的51个玉米自交系, 在吐丝期采取干旱胁迫处理, 研究分析了叶片光合相关参数对干旱胁迫的响应及其与耐旱性的关系。结果表明, 玉米自交系在吐丝期干旱胁迫与正常灌溉条件下P_n、T_r、G_s、C_i、F_v/F_m、Φ_PSII和SPAD的相对值与其耐旱系数呈极显著正相关, WUE相对值与耐旱系数呈极显著负相关, 而q_N和q_P的相对值与耐旱系数不相关; 上述8个叶片光合参数与耐旱系数的逐步回归分析表明,P_n、WUE、F_v/F_m、Φ_PSII和SPAD相对值与耐旱系数在0.01水平显著相关,P_n、WUE、SPAD相对值对耐旱系数有直接贡献, 而F_v/F_m和Φ_PSII对耐旱系数起间接作用。通过上述5个显著相关光合参数将两年三地表现一致的32份自交系的抗旱性分为3类, 第I类8份(H201、H21、英64、吉842、早49、吉8415、东46和沈137)属于耐旱性强的; 第II类15份属于耐旱性较强的; 第III类9份属于耐旱性弱的, 此结果与对应的自交系产量差异分类结果相一致。因此, 玉米自交系吐丝期P_n、WUE、F_v/F_m、Φ_PSII、SPAD的相对值和耐旱系数可作为其耐旱性评价指标。建立了3类耐旱性玉米自交系吐丝期P_n、WUE、F_v/F_m、Φ_PSII、SPAD的相对值与耐旱系数的回归方程, 并明确了其阈值范围。

关键词: 玉米自交系; 吐丝期; 干旱胁迫; 光合指标

Relationship between Leaf Photosynthetic Parameters and Drought Resistance at Silking Stage in Maize Inbred Lines

CHEN Chun-Mei, GAO Ju-Lin^*, SU Zhi-Jun, YU Xiao-Fang, HU Shu-Ping, ZHAO Xiao-Liang

College of Agriculture, Inner Mongolia Agricultural University, Hohhot 010019, China

Fund:

Abstract

To explore drought resistance of maize inbred lines, based on leaf photosynthetic parameters at silking stage, we treated 51 maize inbred lines with drought stress at silking stage in the irrigation area of Tumochuan and Hetao Plain in 2012 and 2013 to analyze response of leaf photosynthetic parameters to drought stress and the relationship between photosynthetic parameters and drought tolerance. The result indicated that at silking stage, no matter under drought and the condition of irrigation,P_n,T_r,G_s,C_i,F_v/F_m,Φ_PSII, and SPAD had a significant and positive correlation with drought resistance coefficient, WUE had a significant and negative correlation with it, whileq_N andq_P had no correlation with it. Stepwise regression analysis on the eight leaf photosynthetic parameters above showed thatP_n, WUE,F_v/F_m,Φ_PSII, and SPAD significantly correlated with drought resistance coefficient atP < 0.01.P_n, WUE, and SPAD directly contributed to drought resistance coefficient, whileF_v/F_m andΦ_PSII contributed indirectly. Thirty-two maize inbred lines were classified into three groups based on different drought resistance, group I with the highest drought resistance contained eight inbred lines (H201, H21, Ying 64, Ji 842, Zao 49, Ji 8415, Dong 46, and Shen 137), group II with the higher drought resistance contained fifteen lines and group III with the lowest drought resistance contained nine lines. The grouping result was consistant with that of yield classification.Therefore, at silking stage,P_n, WUE,F_v/F_m,Φ_PSII, SPAD, and drought resistance coefficient can be used as drought resistance evaluation indices established for the three groups of maize inbred lines. Regression relationship was betweenP_n, WUE,F_v/F_m,Φ_PSII, SPAD, and drought resistance coefficient at silking stage, and the threshold values were confirmed.

Keyword: Maize inbred lines; Silking stage; Drought stress; Photosynthetic parameter

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我国西北地区属于干旱、半干旱地区, 受水文气象条件的制约, 旱灾严重, 每年有亿亩农田和牧草受到干旱的侵袭^{[ 1]}。玉米是我国西北主要粮食作物之一, 干旱也成为影响玉米生长发育和产量提高的第一限制因素^{[ 2]}。

玉米的耐旱性是复杂的数量遗传性状^{[ 3]}, 应通过若干个与耐旱性有关的指标综合评价, 从中挑选出与耐旱性关系最为密切的指标, 作为耐旱品种选育的鉴定指标^{[ 4]}。干旱对作物的影响广泛而深刻, 它影响着作物的光合作用、呼吸作用、水分和养分的吸收运输等各种生理过程^{[ 5]}。光合作用是植株生长的生理基础, 可以反映植株的耐旱性^{[ 6]}。吐丝期是玉米生长发育的关键时期, 此时遇到干旱直接导致植株生长受阻、叶绿素含量减少、光合作用下降^{[ 5, 6, 7]}, 最后影响玉米籽粒产量形成^{[ 8]}。研究表明, 干旱使得气孔关闭^{[ 9]}, 阻碍CO₂进入叶片并降低光合速率。干旱引起光合速率降低, 又可能增加PSII中过剩的光能, 导致PSII的活性和卡尔文循环电子需求间能量的不平衡, 最终损伤光合机构^{[ 9, 10]}。叶绿素荧光参数是在干旱逆境下研究光合作用的有效工具, 它所包含丰富的信息可以反映PSII的原初光化学反应和光合机构状态的变化^{[ 11, 12]}。随着耐旱性研究的不断深入, 玉米品种或自交系抗旱指标的筛选和鉴定也日益受到重视, 但由于鉴定方法受环境条件限制, 苗期的鉴定方法和鉴定指标较多^{[ 13, 14]}, 而玉米的耐旱性以吐丝期最为敏感。

因此, 从光合特性角度, 在玉米自交系吐丝期进行干旱胁迫处理, 探讨玉米自交系吐丝期叶片光合参数指标及其与耐旱性的关系, 明确玉米自交系吐丝期耐旱性评价的光合参数指标, 综合评价玉米自交系的耐旱性。可为选育耐旱玉米自交系提供理论与实践依据。

1 材料与方法

1.1 供试材料

选用沈137 (1)、H21 (2)、中黄204 (3) 、金黄96B (4)、中451 (5)、杂C546 (6) 、E28 (7)、东46 (8)、丹340 (9) 、冀53 (10)、K22 (11)、材11-8 (12)、200B (13)、吉412 (14)、吉8415 (15)、辽3053 (16)、辽5114 (17) 、丹3130 (18)、合344 (19)、3189 (20)、196 (21)、835 (22)、黄野四(23)、5213 (24)、获唐黄(25)、关17 (26)、8002 (27)、吉818 (28)、吉842 (29)、龙抗11 (30)、7884 (31)、甸11 (32)、M14 (33)、英64 (34)、郑22 (35)、临系11 (36)、铁7922 (37)、S7913 (38)、65232宽(39)、CA156 (40)、89-1 (41)、SH15 (42)、8902 (43)、Y75 (44)、H201 (45)、X178 (46)、7537-1 (47)、早49 (48)、四至四(49)、种苗28 (50)和PI10 (51)玉米自交系。

1.2 试验设计

在2012年分别于土默川平原灌区(包头市土默特右旗, 东经110.52°, 北纬40.57°, 简称“2012TMC”)和河套平原灌区(巴彦淖尔市临河区, 东经107.6°, 北纬40.31°, 简称 “2012HT”)及2013年于河套平原灌区(巴彦淖尔市临河区, 东经107.6°, 北纬40.31°, 简称 “2013HT”), 鉴定51份玉米自交系的耐旱性。采用α-lattice设计(3×17), 设干旱胁迫和正常灌溉2个处理, 正常灌溉处理是在播种前、出苗后20 d和40 d、吐丝期、授粉完成后10 d后各充分灌溉一次, 共5次; 干旱胁迫处理除在吐丝期不灌溉外, 其余时期与正常灌溉处理一致, 共4次, 2个处理之间相隔4 m, 每个处理3次重复。单行种植试验材料, 行长4 m, 行距为宽窄行0.7 m和0.3 m, 种植密度为82 500株 hm^-2, 施肥量及其他田间管理按农户模式进行。

1.2.1 降雨量分布供试51份玉米自交系的吐丝期主要集中在7月中下旬, 从2年3点降雨量分布图(图1)可以看出, 2012TMC 7月中下旬降雨3.6 mm, 2012HT在这期间没有降雨, 而2013HT的降雨量为7.9 mm。可见, 2年3点在玉米自交系吐丝期(7月中下旬)降雨量不足8 mm, 不会影响该期干旱胁迫处理的试验结果。

	Figure Option View Download New Window
	图1 玉米自交系整个生育期间降雨量的分布图Fig. 1 Precipitation distribution map during the growing period of maize inbred lines

1.2.2 土壤含水量 Hsiao^{[ 15]}曾将干旱胁迫的程度划分为轻度胁迫, 中度胁迫, 重度胁迫3种类型, 它们的区分标准是土壤含水量减低8%~10%、10%~20%和20%以上。本试验于吐丝期(正常灌溉后5 d)分别测得2012TMC、2012HT以及2013HT的土壤含水量变化(图2), 2年3块试验田土壤含水量以干旱胁迫处理较正常灌溉处理分别下降16.44%、14.99%和11.15%, 均属于中度干旱胁迫。

	Figure Option View Download New Window
	图2 吐丝期土壤含水量CK:正常灌溉; DS: 干旱胁迫。 CK: normal irrigation; DS: drought stress.Fig. 2 Relative soil water content during silking stage2012TMC: the irrigation area of Tumuchuan Plain in 2012; 2012HT: the irrigation area of Hetao Plain in 2012; 2013HT: the irrigation area of Hetao Plain in 2013.

1.3 测定项目与方法

1.3.1 叶片光合速率利用Li-6400XT便携式光合作用测定系统(Li-Cor, 美国)设定人工光源光强1500 μmol m^-2 s^-1, 于吐丝期晴天9:00至17:00时, 选取各自交系生育进程一致、照光均匀的健康植株, 测定穗位叶光合速率( P_n, μmol CO₂ m^-2 s^-1)、气孔导度( G_s, mmol m^-2 s^-1)、胞间CO₂浓度( C_i, μmol mol^-1) 、蒸腾速率( T_r, mmol H₂O m^-2 s^-1), 计算水分利用效率(WUE, µmol CO₂ mmol^-1H₂O) = 光合速率( P_n, μmol CO₂ m^-2 s^-1)蒸腾速率^-1 ( T_r, mmol H₂O m^-2 s^-1)。每个自交系测定3株。

1.3.2 叶绿素荧光参数采用Handy PEA植物效率仪(Hanstatech, 英国), 于吐丝期晴天9:00至17:00时, 测定穗位叶, 测定之前设定程序, 先暗适应30 min, 测定暗适应下的初始荧光 ( F_o)、最大荧光( F_m)。设置600 μmol m^-2s^-1的光强, 测定光适应下的最大荧光( F_m')、最小荧光( F_o')、稳态荧光( F_s)等荧光参数; 参照Demming-Adams等^{[ 16]}方法, 最大光化学效率 F_v/ F_m= ( F_m - F_o)/ F_m, 实际量子产量 Φ_PSII= ( F_m' - F_s)/ F_m', 光化学猝灭系数 q_P= ( F_m' - F_s)/( F_m' - F_o'), 非光化学猝灭系数 q_N=( F_m- F_m')/( F_m - F_o)。每个自交系测定3株。

1.3.3 叶绿素含量(SPAD值) 在玉米吐丝期上午10:00时左右, 使用叶绿素SPAD仪对穗位叶进行测量, 每个自交系测3株。

1.3.4 土壤含水量在吐丝期(2012TMC于7月25日, 2012HT于7月20日, 2013HT于年7月21日)灌溉5 d后, 田间随机取100 cm土深20个点, 测量土壤含水量。土壤含水量 = (原土重-烘干土重)/烘干土重×100%。

1.3.5 耐旱系数DTC Bouslama^{[ 17]}提出的耐旱系数=胁迫下的平均单株产量/非胁迫下的平均单株产量。单株产量为考种实测籽粒重(g 株^-1)。

1.3.6 光合参数相对值光合参数相对值 = 干旱胁迫下玉米自交系光合参数值/正常灌溉下玉米自交系光合参数值。

1.3.7 耐旱性聚类分析法根据多项指标所测数据, 建成聚类图。根据聚类图将参试材料分成耐旱性强的、耐旱性较强的、耐旱性弱的等不同等级^{[ 18]}。

1.4 数据处理

采用 Microsoft Excel 2003计算试验数据平均值, SAS8.0、SPSS11.0和DPS7.05软件进行统计分析。

2 结果与分析

2.1 玉米自交系单株产量的差异分析

从表1可以看出, 玉米自交系在吐丝期干旱胁迫下, 其单株产量均较正常灌溉下降低, 由于自交系间耐旱性的差异, 其产量下降的幅度不同。对正常灌溉与干旱胁迫处理下单株产量差异的 t测验结果表明, 2012TMC差异不显著的有10份, 达到显著水平的有23份, 达到极显著差异的有18份; 2012HT差异不显著的有11份, 达到显著水平的有24份, 达到极显著水平的有16份; 2013HT差异不显著的16份, 达到显著差异的有24份, 达到极显著差异的自交系有11份。

表1 吐丝期干旱胁迫下玉米自交系单株产量(g 株^-1)和耐旱系数 Table 1 Yield per plant (g plant^-1) and DTC for maize inbred lines under drought stress during silking stage

自交系编号 Serial No. of inbred lines	2012TMC			2012HT			2013HT
自交系编号 Serial No. of inbred lines	正常灌溉 Normal irrigation	干旱胁迫 Drought stress	耐旱系数 DTC	正常灌溉 Normal irrigation	干旱胁迫 Drought stress	耐旱系数 DTC	正常灌溉 Normal irrigation	干旱胁迫 Drought stress	耐旱系数 DTC
1	204.5	185.0	0.905	194.7	180.0	0.925	200.3	187.9	0.938
2	244.5	224.0	0.916	245.5	225.0	0.916	252.6	233.9	0.926
3	120.1	53.4^**	0.445	142.8	107.0^*	0.750	193.4	175.0	0.905
4	105.2	45.8^**	0.435	140.6	103.0^*	0.733	142.3	107.6^*	0.756
5	209.7	191.2	0.912	152.0	115.0^*	0.757	156.7	113.1^*	0.722
6	109.7	47.0^**	0.429	174.7	127.0^*	0.727	173.9	121.2^*	0.697
7	97.8	33.0^**	0.338	127.5	41.3^**	0.324	132.8	55.4^**	0.417
8	230.0	209.0	0.909	205.0	190.4	0.929	210.4	193.6	0.920
9	108.1	45.0^**	0.416	114.9	46.8^**	0.407	129.3	67.2^**	0.520
10	185.7	132.0^*	0.711	195.1	183.0	0.938	204.5	192.2	0.940
11	177.1	134.5^*	0.759	177.4	133.0^*	0.750	172.4	130.0^*	0.754
12	173.3	124.0^*	0.716	107.5	43.2^**	0.402	113.4	58.3^**	0.514
13	109.5	45.0^**	0.411	134.5	56.0^**	0.416	142.8	69.8^**	0.489
14	176.7	124.9^*	0.707	132.0	53.5^**	0.405	200.4	181.0	0.903
15	197.8	183.4	0.927	197.0	181.0	0.919	215.3	198.3	0.921
16	178.3	131.7^*	0.738	177.3	131.0^*	0.739	178.3	129.3^*	0.725
17	146.4	67.0^**	0.458	135.1	62.0^**	0.459	139.6	106.5^*	0.763
18	164.5	52.5^**	0.319	113.6	33.3^**	0.293	115.4	42.9^**	0.372
19	185.6	141.0^*	0.760	185.2	169.8	0.917	126.6	65.6^**	0.518
20	183.5	142.0^*	0.774	185.0	144.5^*	0.781	188.3	146.7^*	0.779
21	96.2	33.0^**	0.343	154.5	52.5^**	0.340	130.9	52.8^**	0.403
22	168.0	125.0^*	0.744	153.0	122.4^*	0.800	162.3	128.5^*	0.792
23	180.0	137.0^*	0.761	119.3	55.0^**	0.461	203.5	185.4	0.911
24	188.4	87.5^**	0.465	183.5	143.0^*	0.779	198.7	182.0	0.916
25	151.7	115.0^*	0.758	164.1	125.0^*	0.762	210.4	191.9	0.912
26	111.7	83.5^*	0.748	125.9	95.6^*	0.759	205.8	189.3	0.920
27	122.4	91.5^*	0.747	122.7	91.0^*	0.742	144.5	106.2^*	0.735
28	143.6	107.0^*	0.745	124.2	93.5^*	0.753	136.8	104.1^*	0.761
29	206.8	190.0	0.919	201.4	187.4	0.930	203.6	191.0	0.938
30	109.0	82.5^*	0.757	135.4	104.5^*	0.772	142.3	108.0^*	0.759
31	107.1	43.0^**	0.401	144.4	73.0^**	0.505	105.8	54.7^**	0.517
32	176.6	124.0^*	0.702	165.8	124.5	0.751^*	147.4	113.8^*	0.772
33	185.5	53.5^**	0.288	82.2	24.0^**	0.292	92.5	32.7^**	0.354
34	266.0	249.0	0.936	267.5	250.0	0.935	273.5	255.2	0.933
35	185.5	138.5^*	0.747	184.5	136.5^*	0.740	174.5	128.4^*	0.736
36	153.3	64.0^**	0.417	173.7	128.5^*	0.740	183.4	133.7^*	0.729
37	136.2	102.5^*	0.753	121.2	52.1^**	0.430	184.5	137.5^*	0.745
38	164.6	125.0^*	0.759	140.2	105.0^*	0.749	179.8	138.3^*	0.769
39	111.0	46.6^**	0.420	106.6	46.9^**	0.440	168.4	119.9^*	0.712
40	146.9	111.4^*	0.758	109.0	82.5^*	0.757	165.9	122.4^*	0.738
41	161.3	125.0^*	0.775	190.2	174.5	0.918	185.7	141.5^*	0.762
42	153.5	64.5^**	0.420	102.4	48.4^**	0.473	104.5	52.4^**	0.501
43	208.5	155.0^*	0.743	206.8	148.4^*	0.718	182.4	133.0^*	0.729
44	178.5	134.5^*	0.754	171.0	132.0^*	0.772	174.6	136.4^*	0.781
45	244.7	230.0	0.940	277.0	257.5	0.930	276.5	260.2	0.941
46	134.1	65.0^**	0.485	139.4	66.3^**	0.476	140.5	55.8^**	0.397
47	180.6	135.0^*	0.747	134.3	105.3^*	0.784	152.3	117.1^*	0.769
48	226.5	210.0	0.927	226.5	209.5	0.925	238.5	218.7	0.917
49	208.3	189.0	0.907	186.5	146.5^*	0.786	203.4	157.4	0.774
50	176.9	134.0^*	0.757	133.7	104.2^*	0.779	144.6	106.7^*	0.738
51	185.7	141.0^*	0. 759	162.5	81.5^**	0.501	167.3	129.2^*	0.772

DTC: drought tolerance coefficient; 2012TMC: the irrigation area of Tumuchuan Plain in 2012; 2012HT: the irrigation area of Hetao Plain in 2012; 2013HT: the irrigation area of Hetao Plain in 2013.^* and^** significantly different from the control at 0.05 and 0.01 probobility levels, within the same inbred line, respectively.

2012TMC: 2012年土默川平原; 2012HT: 2012年河套平原灌区; 2013HT: 2013年河套平原灌区。^*和^**分别表示与对照在0.05和0.01水平上差异显著性同一自交系内的比较。

表1 吐丝期干旱胁迫下玉米自交系单株产量(g 株^-1)和耐旱系数 Table 1 Yield per plant (g plant^-1) and DTC for maize inbred lines under drought stress during silking stage

2年3点单株产量差异表现一致的自交系有32份, 其中8份自交系(H201、H21、英64、吉842、早49、吉8415、东46和沈137)差异不显著, 15份自交系(龙抗11、CA156、835、3189、吉818、S7913、K22、辽3053、7537-1、种苗28、Y75、8902、8002、甸11和郑22)差异显著, 9份自交系(7884、200B、H15、M14、丹3130、X178、丹340、196和E28)差异极显著。

2.2 玉米自交系吐丝期叶片光合参数的方差分析

对2012TMC和2012HT的51份玉米自交系各光合参数进行方差分析(表2)表明, 所有参数在地点、自交系×地点间差异均不显著; 而 q_P和 q_N在地点、处理、自交系、自交系×地点和自交系×处理间差异均不显著, 其余参数在处理、自交系和自交系×处理间均达到显著或极显著水平, 尤其在自交系×处理间均达到极显著水平。

表2 2012TMC与2012HT玉米自交系吐丝期光合参数的方差分析 Table 2 Variance analysis of photosynthetic parameters in maize inbred lines at silking stage in 2012TMC and 2012HT

对2012HT和2013HT的51份玉米自交系各光合参数进行方差分析(表3)表明, 所有参数在年份和自交系×年份间差异均不显著; 而 q_P和 q_N在年份、处理、自交系、自交系×年份和自交系×处理间差异均不显著, 其余参数在处理、自交系和自交系×处理间均达到显著或极显著水平, 尤其在自交系×处理间均达到极显著水平。

表3 2012HT与2013HT玉米自交系吐丝期光合参数的方差分析 Table 3 Variance analysis of photosynthetic parameters in maize inbred lines at silking stage in 2012TMC and 2013HT

2.3 玉米自交系吐丝期叶片光合参数与耐旱系数的关系

玉米自交系吐丝期各光合参数相对值与耐旱系数的线性回归分析结果(表4)表明, 玉米自交系在吐丝期干旱胁迫下, P_n、 G_s、 C_i、 T_r、 F_v/ F_m、 Φ_PSII和SPAD值的相对值与DTC均极显著正相关; WUE的相对值与DTC极显著负相关; 而 q_P、 q_N的相对值与DTC的相关性不显著。

表4 玉米自交系吐丝期各光合参数相对值与耐旱系数的关系 Table 4 Relationships between relative value of photosynthesis in maize inbred lines at silking stage

相关分析表明, P_n、 C_i、 G_s、 T_r、WUE、 F_v/ F_m、 Φ_PSII、SPAD的相对值与DTC极显著相关, 进一步对2012TMC、2012HT和2013HT 2年3点的 P_n、 C_i、 G_s、 T_r、WUE、 F_v/ F_m、 Φ_PSII、SPAD 8个光合参数的相对值与DTC进行逐步回归分析, 建立如下回归方程。

2012TMC: DTC = 0.354 P_n+0.187 C_i+0.204 G_s+ 0.256 T_r-0.382WUE+0.0.274 F_v/ F_m+0.268 Φ_PSII+0.337SPAD, F₁=9.825, P₁=0.007;2012HT: DTC=0.324 P_n+0.216 T_r-0.374WUE+0.286 F_v/ F_m+0.243 Φ_PSII+0.369SPAD, F₂=9.186, P₂=0.006;2013HT: DTC=0.367 P_n-0.391WUE+0.256 F_v/ F_m+ 0.225 Φ_PSII+0.342SPAD, F₃=9.937, P₃=0.004;2012TMC的 P_n、 C_i、 G_s、 T_r、WUE、 F_v/ F_m、 Φ_PSII、SPAD 8个光合参数相对值与耐旱系数均极显著相关, 2012HT的 P_n、 T_r、WUE、 F_v/ F_m、 Φ_PSII和SPAD 6个光合参数相对值与耐旱系数极显著相关, 而2013HT的 P_n、WUE、 F_v/ F_m、 Φ_PSII和SPAD 5个光合参数相对值与耐旱系数极显著相关。综合2年3点逐步回归分析结果表明, P_n、WUE、 F_v/ F_m、 Φ_PSII和SPAD 5个光合参数更具有一致性, 可将这5个光合参数作为评价玉米自交系吐丝期耐旱性的光合参数。

2.4 玉米自交系吐丝期叶片光合参数与耐旱系数的通径分析

表5表明, P_n、WUE、 F_v/ F_m、 Φ_PSII和SPAD 5个光合参数相对值决定了单株产量变异的98.73%, 其中以WUE相对值对耐旱系数的直接贡献最大, 其Pi达到0.9825; 其次为 P_n, 其Pi达到0.6312; 再次为SPAD, 其Pi达到0.4276; 而 F_v/ F_m和 Φ_PSII相对值对耐旱系数的直接贡献则很小, 其对耐旱系数的贡献主要通过WUE和 P_n来实现, 其间接通径系数分别为 P_1-2-y=0.5728, P_3-2-y=0.3726, P_4-2-y=0.1825, P_5-2-y=0.4125。由此可以看出, 玉米自交系耐旱育种主要应注重WUE、 P_n和SPAD的选择。由于 F_v/ F_m和 Φ_PSII对WUE、 P_n和SPAD有间接贡献, 所以对 F_v/ F_m和 Φ_PSII进行间接选择也是很有效的。

表5 玉米自交系吐丝期叶片光合参数对耐旱系数的直接和间接通径系数 Table 5 Drought resistance related parameters to the direct and indirect path coefficient of yield per plant

2.5 玉米自交系耐旱性的综合评价

用 P_n、WUE、SPAD、 F_v/ F_m、 Φ_PSII值5个光合参数的相对值, 通过最短距离法对所选用的51个玉米自交系进行聚类分析, 可将其划分为3类(表6)。

表6 51份玉米自交系耐旱性的分类 Table 6 Classification of drought tolerance for 51 maize inbred lines

年份、地区 Year and place	第I类 Group I	第II类 Group II	第III类 Group III
2012TMC	沈137、H21、吉842、英64、吉8415、H201、中451、东46、早49、四至四共10份	冀53、8002、吉412、吉818、龙抗11、甸11、CA156、89-1、S7913、获唐黄、铁7922、Y75、黄野四、K22、合344、PI10、3189、8902、种苗28、835、郑22、关17、辽3053、材11-8、7537-1共25份	中黄204、SH15、65232宽、丹340、杂C546、M14、金黄96B、E28、200B、临系11、丹3130、X178、196、7884、5213、辽5114共16份
2012HT	沈137、H21、吉842、英64、吉8415、H201、东46、早49、冀53、合344、89-1共11份	K22、辽3053、3189、835、8002、吉818、龙抗11、甸11、郑22、S7913、CA156、8902、Y75、种苗28、7537-1、中黄204、临系11、四至四、5213、金黄96B、中451、获唐黄、杂C546、S7913共24份	E28、丹340、200B、丹3130、196、7884、M14、SH15、X178、材11-8、铁7922、吉412、PI10、黄野四、辽5114、65232宽共16份
2013HT	沈137、H21、东46、吉8415、吉842、英64、H201、早49、四至四、黄野四、获唐黄、中黄204共12份	K22、辽3053、3189、835、8002、吉818、龙抗11、甸11、郑22、S7913、CA156、8902、Y75、种苗28、7537-1、冀53、材11-8、PI10、吉412、金黄96B、中451、5213、杂C546、89-1、郑22、铁7922、辽5114共27份	E28、丹340、200B、丹3130、196、7884、M14、SH15、X178、材11-8、临系11、合344共12份
2012TMC、2012HT和2013HT一致性 Consistence of 2012TMC, 2012HT, and 2013HT	沈137、H21、东46、吉8415、吉842、英64、H201、早49共8份	K22、辽3053、3189、835、8002、吉818、龙抗11、甸11、郑22、S7913、CA156、8902、Y75、种苗28、7537-1共15份	E28、丹340、200B、丹3130、196、7884、M14、SH15、X178、共9份

2012TMC: the irrigation area of Tumuchuan Plain in 2012; 2012HT: the irrigation area of Hetao Plain in 2012; 2013HT: the irrigation area of Hetao Plain in 2013.

2012TMC: 2012年土默川平原; 2012HT: 2012年河套平原灌区; 2013HT: 2013年河套平原灌区。

表6 51份玉米自交系耐旱性的分类 Table 6 Classification of drought tolerance for 51 maize inbred lines

2012TMC、2012HT和2013HT 2年3点表现均一致的自交系有32份, 其中第1类8份(沈137、H21、东46、吉8415、吉842、英64、H201、早49), 耐旱性强; 第2类15份(K22、辽3053、3189、835、8002、吉818、龙抗11、甸11、郑22、S7913、CA156、8902、Y75、种苗28、7537-1), 耐旱性较强; 第3类10份(E28、丹340、200B、丹3130、196、7884、M14、SH15、X178), 耐旱性弱。其余19份自交系在2年3点表现不一致。

3 讨论

3.1 玉米自交系吐丝期耐旱性评价指标的选用

耐旱系数^{[ 19]}可反映植物对干旱的敏感程度。一个品种耐旱系数高, 耐旱性强, 稳产性好, 即在水分胁迫条件下, 减产的幅度较小。由于植物的耐旱性是由多种因素相互作用而构成的一个较为复杂的综合性状, 不同指标对耐旱性的贡献也不一样^{[ 20]}。植物的耐旱机制很复杂, 不同品种其耐旱机制及同一品种在不同环境不同生育时期其耐旱机制都存在差异^{[ 21]}。因此, 在耐旱性鉴定中, 应从形态、生理、生化等众多指标中筛选出对耐旱性有显著影响的几个重要指标, 综合分析判断才能更合理有效。

本试验利用玉米自交系吐丝期干旱胁迫与正常灌溉处理下产量及光合参数的相对值综合分析, 可以消除自交系间固有的差异, 更有效评价耐旱性。

综合分析51份玉米自交系2年3点的单株产量差异, 表现均一致的自交系共有32份, 其中8份自交系(H201、H21、英64、吉842、早49、吉8415、东46和沈137)差异不显著, 自交系耐旱性强, 耐旱系数大; 15份自交系(龙抗11、CA156、835、3189、吉818、S7913、K22、辽3053、7537-1、种苗28、Y75、8902、8002、甸11和郑22)差异显著, 自交系耐旱性较强, 耐旱系数较大; 9份自交系(7884、200B、H15、M14、丹3130、X178、丹340、196和E28)差异极显著, 自交系耐旱性弱, 耐旱系数小。

通过相关分析显示, 玉米自交系吐丝期叶片光合参数中, P_n、 C_i、 G_s、 T_r、WUE、 F_v/ F_m、 Φ_PSII、SPAD 8个光合参数相对值与耐旱系数极显著相关; 对这8个指标进一步进行逐步回归分析显示, P_n、WUE、SPAD、 F_v/ F_m、 Φ_PSII 5个光合参数作为评价玉米自交系吐丝期耐旱性的光合参数更具一致性; 同时, 利用5个光合参数对51个自交系进行聚类分析, 评价分类结果与实际产量差异评价结果完全一致。

3.2 不同耐旱类型玉米自交系的耐旱系数与吐丝期叶片光合参数的相关性

作物受到干旱胁迫直接导致产量下降, 而产量主要来源于光合产物的积累, 因此干旱影响着作物的光合作用、呼吸作用、水分和养分的吸收运输等各种生理过程^{[ 22]}。光合作用是植株生长的生理基础, 可以反映植株的耐旱性^{[ 23]}。前人研究表明, 在吐丝期干旱胁迫下气孔导度下降, 使光合速率和蒸腾速率都下降, 蒸腾作用降低的程度比光合作用降低的程度大, 利于水分利用效率的提高^{[ 24, 25]}。陈建民等研究认为在干旱条件下玉米叶片的光合作用受抑制, 光合速率下降, 耐旱性较强的品种能维持较高的光合速率, 玉米叶片的叶绿素含量较耐旱性较差的品种下降幅度小^{[ 21, 22, 23, 24, 25, 26]}。相关性分析表明, 在干旱处理中, 叶绿素含量的降幅与品种耐旱性显著相关^{[ 27]}。本试验结果表明, 玉米自交系吐丝期 P_n、SPAD、 F_v/ F_m、 Φ_PSII与其耐旱系数极显著正相关, 而WUE相对值与其耐旱系数极显著负相关; P_n、WUE、SPAD相对值对耐旱系数有直接贡献, 而 F_v/ F_m和 Φ_PSII对耐旱系数起间接作用。将2年3点抗旱类型表现一致的32份玉米自交系吐丝期 P_n、SPAD、 F_v/ F_m、 Φ_PSII 5个光合参数相对值与耐旱系数进行多元回归分析, 回归方程如下。

第一类(耐旱性最强的): DTC=0.425 P_n-0.526 WUE+0.0.314 F_v/ F_m+0.275 Φ_PSII+0.396SPAD, F₁=9.936, P₁=0.004;第二类(耐旱性较强的): DTC=0.386 P_n-0.437 WUE+0.315 F_v/ F_m+0.296 Φ_PSII+0.364SPAD, F₂=9.912, P₂=0.007;第三类(耐旱性最弱的): DTC=0.463 P_n-0.501 WUE+0.364 F_v/ F_m+0.301 Φ_PSII+0.425SPAD, F₃=9.982, P₃=0.003;结果表明, 回归方程在0.01水平上均达到显著, 这5个光合参数的相对值对玉米自交系耐旱性更有预见性。

3.3 不同耐旱类型玉米自交系吐丝期耐旱相关光合参数阈值范围

多种作物上的耐旱性研究表明, 作物耐旱性受多种因素影响, 以单一指标评价玉米自交系吐丝期的耐旱能力具有一定的片面性, 而多指标评价又过于繁琐和低效^{[ 28, 29]}。且近年来, 国内外学者对耐旱性指标及方法研究较多, 但如何快速判断不同玉米自交系的耐旱性未形成完整的指标体系。本试验通过对耐旱性分类结果一致的32份玉米自交系吐丝期 P_n、WUE、 F_v/ F_m、 Φ_PSII、SPAD相对值和耐旱系数的量化, 确定其阈值范围(表7)从而评价玉米自交系吐丝期的耐旱性, 这对快速筛选耐旱性强的玉米自交系及辅助耐旱育种具有重要意义。

表7 三类玉米自交系吐丝期各光合参数相对值与耐旱系数的阈值范围 Table 7 Treshold of relative values spinning of photosynthetic parameters and drought resistance coefficient of maize inbred lines in three kinds of maize inbred lines during silking

4 结论

玉米自交系吐丝期 P_n、WUE、 F_v/ F_m、 Φ_PSII、SPAD的相对值和耐旱系数可作为其耐旱性评价指标。玉米自交系吐丝期 P_n、SPAD、 F_v/ F_m、 Φ_PSII与其耐旱系数极显著正相关, 而WUE相对值与其耐旱系数极显著负相关; P_n、WUE、SPAD相对值对耐旱系数有直接贡献, 而 F_v/ F_m和 Φ_PSII对耐旱系数起间接作用。同时, 明确了耐旱性强的、耐旱性较强的、耐旱性弱的三类玉米自交系吐丝期 P_n、WUE、 F_v/ F_m、 Φ_PSII、SPAD的相对值和耐旱系数阈值范围。51份玉米自交系中, 有8份(H201、H21、英64、吉842、早49、吉8415、东46和沈137)是耐旱性强的。

The authors have declared that no competing interests exist.

作者已声明无竞争性利益关系。The authors have declared that no competing interests exist.

参考文献

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[1]	Campos H, Cooper M, Habben J E, Edmeades G O, Schussler J R. Improving drought tolerance in maize: a view from industry. Field Crops Res, 2004, 90: 19-34 [本文引用:1] [JCR: 2.474]
[2]	Welsh C E, McMillan L. Accelerating the inbreeding of multi- parental recombinant inbred lines generated by sibling matings. Genes, Genomes, Genetics (Bethesda), 2012, 2: 191-198 [本文引用:1]
[3]	Henry T, Singh S P. Comparison of sources and lines selected for drought resistance in common bean. Crop Sci, 2002, 42: 64-70 [本文引用:1] [JCR: 1.513]
[4]	Lee M, Jung J H, Han D Y, Seo P J, Park W J, Park C M. Activation of a flavin monooxygenase gene YUCCA7 enhances drought resistance in Arabidopsis. Planta, 2012, 235: 925-938 [本文引用:1] [JCR: 3.347]
[5]	De Diego N, Pérez-Alfocea F, Cantero E, Lacuesta M, Moncaleán P. Physiological response to drought in radiata pine: phytohormone implication at leaf level. Tree Physiol, 2012, 32: 435-449 [本文引用:2] [JCR: 2.853]
[6]	Medrano H, Escalona J M, Bota J, Gulías J, Flexas J. Regulation of photosynthesis of C₃ plants in response to progressive drought: stomatal conductance as a reference parameter. Ann Bot, 2002, 89: 895-905 [本文引用:2] [JCR: 0.657]
[7]	Saint Pierre C, Crossa J L, Bonnett D, Yamaguchi-Shinozaki K, Reynolds M P. Phenotyping transgenic wheat for drought resistance. J Exp Bot, 2012, 63: 1799-1808 [本文引用:1] [JCR: 5.242]
[8]	Deeba F, Pand ey A K, Ranjan S, Mishra A, Singh R, Sharma Y K, Shirke P A, Pand ey V. Physiological and proteomic responses of cotton (Gossypium herbaceum L. ) to drought stress. Plant Physiol Biochem, 2012, 53: 6-18 [本文引用:1]
[9]	Sjursen H, Bayley M, Holmstrup M. Enhanced drought tolerance of a soil-dwelling springtail by pre-acclimation to a mild drought stress. J Insect Physiol, 2001, 47: 1021-1027 [本文引用:2] [JCR: 2.379]
[10]	Aroca R, Irigoyen J J, Sánchez-Díaz M. Drought enhances maize chilling tolerance: II. Photosynthetic traits and protective mechanisms against oxidative stress. Physiol Plant, 2003, 117: 540-549 [本文引用:1] [JCR: 6.555]
[11]	Baker N R, Rosenqvist E. Application of chlorophyll fluorescencecan improve crop production strategies: an examination of future possibilities. J Exp Bot, 2004, 55: 1607-1621 [本文引用:1] [JCR: 5.242]
[12]	Schreiber U, Schliwa U, Bilger W. Continuous recording of photochemical and non photochemical chlorophyll fluorescence equenching with a new type of modulation fluorometer. Photosynth Res, 1986, 10: 51-62 [本文引用:1] [JCR: 3.15]
[13]	Selmani A, Wasson C E. Daytime chlorophyll fluorescence measurement in field-grown maize and its genetic variability under well-water and water-stressed conditions. Field Crops Res, 2003, 31: 173-184 [本文引用:1] [JCR: 2.474]
[14]	胡秀丽, 李艳辉, 杨海荣, 刘全军, 李潮海. HSP70可提高干旱高温复合胁迫诱导的玉米叶片抗氧化防护能力. 作物学报, 2010, 36: 636-644 Hu X L, Li Y H, Yang H R, Liu Q J, Li C H. Heat shock protein 70 may improve the ability of antioxidant defense induced by the combination of drought and heat in maize leaves. Acta Agron Sin, 2010, 36: 636-644 (in Chinese with English abstract) [本文引用:1] [CJCR: 1.667]
[15]	Hsiao. Plant responses to water stress. Annu Rev Plant Physical, 1973, 24: 570-579 [本文引用:1]
[16]	Harrigan G G, Ridley W P, Miller K D, Sorbet R, Riordan S G, Nemeth M A, Reeves W, Pester T A. The forage and grain of MON 87460, a drought-tolerant corn hybrid, are compositionally equivalent to that of conventional corn. J Agric Food Chem, 2009, 57: 9754-9763 [本文引用:1] [JCR: 2.906]
[17]	张守仁. 叶绿素荧光动力学参数的意义及讨论. 植物学通报, 1999, 16: 444-448 Zhang S R. A discussion of chlorophyll fluorescence kinetics parameter and their significance. Chin Bull Bot, 1999, 16: 444-448 (in Chinese) [本文引用:1]
[18]	Lu Y L, Hao Z F, Xie C X. Large-scale screening for maize drought resistance using multiple selection criteria evaluated under water-stressed and well-watered environments. Field Crops Res, 2011, 124: 37-45 [本文引用:1] [JCR: 2.474]
[19]	许大全. 光合作用效率. 上海: 上海科学技术出版社, 2009 Xu D Q. Photosynthetic Efficiency. Shanghai: Shanghai Scientific and Technical Publishers, 2009 (in Chinese) [本文引用:1]
[20]	Harp R E, Poroyko V, Hejlek L G, Spollen W G, Springer G K, Bohnert H J, Nguyen H T. Root growth maintenance during water deficits: physiology to functional genomies. J Exp Bot, 2004, 55: 2343-2351 [本文引用:1] [JCR: 5.242]
[21]	陈建明, 俞晓平, 程家安. 叶绿素荧光动力学及其在植物抗逆生理研究中的应用. 浙江农业学报, 2006, 18(1): 51-55 Chen J M, Yu X P, Cheng J A. The application of chlorophyll fluorescence kinetics in the study of physiological responses of plants to environmental stresses. Acta Agric Zhejiangensis, 2006, 18(1): 51-55 (in Chinese) [本文引用:2] [CJCR: 0.602]
[22]	白向历, 孙世贤, 杨国航, 刘明, 张振平, 齐华. 不同生育时期水分胁迫对玉米产量及生长发育的影响. 玉米科学, 2009, 17(2): 60-63 Bai X L, Sun S X, Yang G H, Liu M, Zhang Z P, Qi H. Effect of water stress on maize yield during different growing stages. J Maize Sci, 2009, 17(2): 60-63 (in Chinese with English abstract) [本文引用:2] [CJCR: 0.965]
[23]	孙璐, 周宇飞, 汪澈, 肖木辑, 陶冶, 许文娟, 黄瑞冬. 高粱品种萌发期耐盐性筛选与鉴定. 中国农业科学, 2012, 45: 1714-1722 Sun L, Zhou Y F, Wang C, Xiao M J, Tao Y, Xu W J, Huang R D. Screening and identification of sorghum cultivars for salinity tolerance during germination. Sci Agric Sin, 2012, 45: 1714-1722 (in Chinese with English abstract) [本文引用:2] [CJCR: 1.889]
[24]	Baquedano F J, Castillo F J. Comparative ecophysiological effects of drought on seedlings of the Mediterranean water-saver Pinus halepensis and water-spenders Quercus coccifera and Quercus ilex. Trees, 2006, 20: 689-700 [本文引用:2] [JCR: 1.925]
[25]	付学琴, 贺浩华, 文飘, 罗向东, 谢建坤. 东乡野生稻回交重组系的抗旱性评价体系. 应用生态学报, 2012, 23: 1277-1285 Fu X Q, He H H, Wen P, Luo X D, Xie J K. Drought resistance evaluation system for backcross lines of Dongxiang common wild rice (Oryza rufipogon Griff. ). Chin J Appl Ecol, 2012, 23: 1277-1285 (in Chinese with English abstract) [本文引用:2] [CJCR: 1.742]
[26]	李合生. 植物生理生化实验原理和技术. 北京: 高等教育出版社, 2000 Li H S. Experimental Principle and Technique for Plant Physio-logy and Biochemistry. Beijing: Higher Education Press, 2000 (in Chinese) [本文引用:1]
[27]	Bouslama M, Schapaugh W T Jr. Stress tolerance in soybeans: I. Evaluation of three screening techniques for heat and drought tolerance. Crop Sci, 1984, 24: 933-937 [本文引用:1] [JCR: 1.513]
[28]	龚明. 作物抗旱性鉴定方法与指标及其综合评价. 云南农业大学学报, 1989, 4(1): 73-81 Gong M. Screening methods and index of drought resistance in crops and comprehensive evaluation. J Yunnan Agric Univ, 1989, 4(11): 73-81 (in Chinese) [本文引用:1] [CJCR: 0.661]
[29]	Pollard D A. Design and construction of recombinant inbred lines. Methods Mol Biol, 2012, 871: 31-39 [本文引用:1]

2004

2.474

0.0

. 2004, 90:19-34 DOI:10.1016/j.fcr.2004.07.003

Improving drought tolerance in maize: a view from industry

Abstract Significant yield losses in maize ( Zea mays L.) from drought are expected to increase with global climate change as temperatures rise and rainfall distribution changes in key traditional production areas. The success of conventional crop improvement over the past 50 years for drought tolerance forms a baseline against which new genetic methods must be compared. Selection based on performance in multi-environment trials (MET) has increased grain yield under drought through increased yield potential and kernel set, rapid silk exertion, and reduced barrenness, though at a lower rate than under optimal conditions. Knowledge of the physiology of drought tolerance has been used to dissect the trait into a series of key processes. This has been complemented by genetic dissection through the identification of QTL associated with these same traits. Both have been used to identify suitable organ- and temporal-specific promoters and structural genes. Phenotyping capacity has not kept pace with the exponential increase in genotypic knowledge, and large-scale managed stress environments (MSE) are now considered essential to further progress. These environments provide ideal settings for conducting massively parallel transcript profiling studies, and for validating candidate regions and genes. Genetic and crop physiological models of key processes are now being used to confirm the value of traits for target environments, and to suggest efficient breeding strategies. Studies of gene to phenotype relationships suggest that most putative drought tolerance QTL identified thus far are likely to have limited utility for applied breeding because of their dependency on genetic background or their sensitivity to the environment, coupled with a general lack of understanding of the biophysical bases of these context dependencies. Furthermore, the sample of weather conditions encountered during progeny selection within the multi environment testing of conventional breeding programs can profoundly affect allele frequency in breeding populations and the stress tolerance of elite commercial products. We conclude that while gains in kernels per plant can be made by exploiting native genetic variation among elite breeding lines, improvements in functional stay-green or in root distribution and function may require additional genetic variation from outside the species. Genomic tools and the use of model plants are considered indispensable tools in this search for new ways of optimizing maize yield under stress.

... 我国西北地区属于干旱、半干旱地区, 受水文气象条件的制约, 旱灾严重, 每年有亿亩农田和牧草受到干旱的侵袭^[1] ...

2012

0.0

... 玉米是我国西北主要粮食作物之一, 干旱也成为影响玉米生长发育和产量提高的第一限制因素^[2] ...

2002

1.513

0.0

... 玉米的耐旱性是复杂的数量遗传性状^[3], 应通过若干个与耐旱性有关的指标综合评价, 从中挑选出与耐旱性关系最为密切的指标, 作为耐旱品种选育的鉴定指标^[4] ...

2012

3.347

0.0

2012

2.853

0.0

... 干旱对作物的影响广泛而深刻, 它影响着作物的光合作用、呼吸作用、水分和养分的吸收运输等各种生理过程^[5] ...

... 吐丝期是玉米生长发育的关键时期, 此时遇到干旱直接导致植株生长受阻、叶绿素含量减少、光合作用下降^[5,6,7], 最后影响玉米籽粒产量形成^[8] ...

2002

0.657

0.0

... 光合作用是植株生长的生理基础, 可以反映植株的耐旱性^[6] ...

... 吐丝期是玉米生长发育的关键时期, 此时遇到干旱直接导致植株生长受阻、叶绿素含量减少、光合作用下降^[5,6,7], 最后影响玉米籽粒产量形成^[8] ...

2012

5.242

0.0

... 吐丝期是玉米生长发育的关键时期, 此时遇到干旱直接导致植株生长受阻、叶绿素含量减少、光合作用下降^[5,6,7], 最后影响玉米籽粒产量形成^[8] ...

2012

0.0

. 2012, 53:null-null

Physiological and proteomic responses of cotton (Gossypium herbaceum L.) to drought stress

... 吐丝期是玉米生长发育的关键时期, 此时遇到干旱直接导致植株生长受阻、叶绿素含量减少、光合作用下降^[5,6,7], 最后影响玉米籽粒产量形成^[8] ...

2001

2.379

0.0

. 2001, 47:null-null

Enhanced drought tolerance of a soil-dwelling springtail by pre-acclimation to a mild drought stress

... 研究表明, 干旱使得气孔关闭^[9], 阻碍CO₂进入叶片并降低光合速率 ...

... 干旱引起光合速率降低, 又可能增加PSII中过剩的光能, 导致PSII的活性和卡尔文循环电子需求间能量的不平衡, 最终损伤光合机构^[9,10] ...

2003

6.555

0.0

. 2003, 117(4):540-549

Drought enhances maize chilling tolerance. II. Photosynthetic traits and protective mechanisms against oxidative stress

Ricardo Aroca 2 ,Juan José Irigoyen 1 andManuel Sánchez-Díaz *

1 Departamento de Fisiología Vegetal, Universidad de Navarra, C/Irunlarrea s/n 31008, Pamplona, Spain 2 Present address: Division of Biology, University of California at San Diego, La Jolla CA 92093–0116, USA * * Corresponding author, e-mail: msanchez@unav.es

> In the present research we studied the photosynthetic traits and protective mechanisms against oxidative stress in two maize ( Zea mays L.) genotypes differing in chilling sensitivity (Z7, tolerant and Penjalinan, sensitive) subjected to 5°C for 5 days, with or without pretreatment by drought. The drought pretreatment decreased the symptoms of chilling injury in Penjalinan plants estimated as necrotic leaf area and maximum quantum yield of photosystem II. Furthermore, drought pretreatment diminished the level of lipid peroxidation caused by chilling in Penjalinan plants. After one day of recovery from chilling the Z7 and drought-pretreated Penjalinan plants showed higher net photosynthesis rates than the non-drought-pretreated Penjalinan plants, thereby decreasing the probability of generating reactive oxygen species. The greater net photosynthesis was correlated with the greater NADP-malate dehydrogenase activity. No differences in either the de-epoxidation state of the xanthophyll cycle or the antioxidant enzyme activities were found among the chilled groups of plants. However, a drastic decrease in ascorbate content was observed in chilled Penjalinan plants without drought pretreatment. As we found an increase of H 2 O 2 content after drought pretreatment, we suggest its involvement as a signal in the drought-enhanced chilling tolerance of maize.

... 干旱引起光合速率降低, 又可能增加PSII中过剩的光能, 导致PSII的活性和卡尔文循环电子需求间能量的不平衡, 最终损伤光合机构^[9,10] ...

2004

5.242

0.0

... 叶绿素荧光参数是在干旱逆境下研究光合作用的有效工具, 它所包含丰富的信息可以反映PSII的原初光化学反应和光合机构状态的变化^[11,12] ...

1986

3.15

0.0

Photosynth Res. 1986, 10(1-2):51-62

Continuous recording of photochemical and non-photochemical chlorophyll fluorescence quenching with a new type of modulation fluorometer

U. Schreiber (1) , U. Schliwa (1) , W. Bilger (1)

1. Institut für Botanik, Mittlerer Dallenbergweg 64, D-8700, Würzburg, FRG

A newly developed fluorescence measuring system is employed for the recording of chlorophyll fluorescence induction kinetics (Kautsky-effect) and for the continuous determination of the photochemical and non-photochemical components of fluorescence quenching. The measuring system, which is based on a pulse modulation principle, selectively monitors the fluorescence yield of a weak measuring beam and is not affected even by extremely high intensities of actinic light. By repetitive application of short light pulses of saturating intensity, the fluorescence yield at complete suppression of photochemical quenching is repetitively recorded, allowing the determination of continuous plots of photochemical quenching and non-photochemical quenching. Such plots are compared with the time courses of variable fluorescence at different intensities of actinic illumination. The differences between the observed kinetics are discussed. It is shown that the modulation fluorometer, in combination with the application of saturating light pulses, provides essential information beyond that obtained with conventional chlorophyll fluorometers.

... 叶绿素荧光参数是在干旱逆境下研究光合作用的有效工具, 它所包含丰富的信息可以反映PSII的原初光化学反应和光合机构状态的变化^[11,12] ...

2003

2.474

0.0

... 随着耐旱性研究的不断深入, 玉米品种或自交系抗旱指标的筛选和鉴定也日益受到重视, 但由于鉴定方法受环境条件限制, 苗期的鉴定方法和鉴定指标较多^[13,14], 而玉米的耐旱性以吐丝期最为敏感 ...

2010

0.0

1.667

. 2010, 36:636-644 DOI:10.3724/SP.J.1006.2010.00636

Heat shock protein 70 may improve the ability of antioxidant defense induced by the combination of drought and heat in maize leaves

Hu X L , Li Y H , Yang H R , Liu Q J , Li C H

1 College of Life Science, Henan Agricultural University; 2 College of Agronomy, Henan Agricultural University, Zhengzhou 450002, China

In order to determine the mechanism of heat shock protein (HSP70) increasing crops endurance to the combination of drought and heat, we investigated the physiological characteristics of four maize varieties with different responses to drought and heat stresses. The results are as follows: (1) Under drought, heat, the combination of drought and heat, the increase of malondialdelehyde (MDA) content in leaf was the lowest in Zhuyu 309 without endurance to three stresses and the highest in Longyu 602 with endurance to three stresses; under drought, leaf MDA increase in Zhengdan958 with drought-endurance was less than that in Xundan 20 leaves with heat-endurance; under heat, leaf MDA increase was more in Zhengdan 958 than in Xundan20. (2) In Zhengdan958, Xundan20, Longyu602 leaves, the increase of ascorbate peroxidese (APX), glutathione reductase (GR), superoxide dismutase (SOD), catalase (CAT) activities was more than that in Zhuyu 309 leaves under drought, heat, the combination of drought and heat; under drought, APX, GR, SOD, CAT activities of Zhengdan 958 leaves increased significantly more than those of Xundan 20’, but those were contrary under heat; under the combination of drought and heat, APX, GR, SOD activities of Longyu 602 leaves increased significantly more than those of Zhengdan 958 and Xundan 20. (3) The pretreatment with HSP70 inhibitor quercetin (Q) significantly inhibited the increase of antioxidant enzymes activities in leaves of 4 maize varieties exposed to the three stresses. These results suggested that HSP70 involved in the increase of antioxidant enzyme activity in leaves of 4 maize varieties exposed to drought, heat and their combination, and APX, GR, SOD activities could be used as chemical and biological indicators to evaluate the crop endurance to drought, heat, and the combination of drought and heat stresses.

为确定热休克蛋白70 (HSP70)提高作物耐干旱高温复合胁迫的机制，对干旱、高温反应不同的4个玉米品种的生理特性进行了研究。结果显示：(1) 在干旱、高温、干旱高温复合胁迫条件下，叶片丙二醛(MDA)增加量以隆玉602最低，驻玉309最高；在干旱胁迫条件下，郑单958叶片MDA含量低于浚单20，而在高温胁迫条件下，浚单20叶片MDA含量低于郑单958。(2) 在干旱、高温、干旱高温复合胁迫条件下，隆玉602、郑单958、浚单20三个品种叶片抗氧化防护系统如抗坏血酸过氧化物酶(APX)、谷胱苷肽还原酶(GR)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性增加量均高于驻玉309；在干旱条件下，郑单958叶片APX、GR、SOD、CAT活性增加量显著高于浚单20，在高温条件下，两个品种的表现则相反；在干旱高温复合胁迫条件下，隆玉602 叶片APX、GR、SOD活性增加量显著高于郑单958和浚单20。(3) HSP70抑制剂斛皮素(Quercetin, Q)预处理显著抑制了3种胁迫诱导的4个品种叶片抗氧化酶活性的增加。这些研究结果暗示HSP70提高了干旱、高温、干旱高温复合胁迫诱导的抗氧化防护酶活性，且APX、GR、SOD 这3个抗氧化防护酶活性可以作为评价作物耐干旱、高温和干旱高温复合胁迫的生化指标。

1973

0.0

... 2 土壤含水量 Hsiao^[15]曾将干旱胁迫的程度划分为轻度胁迫, 中度胁迫, 重度胁迫3种类型, 它们的区分标准是土壤含水量减低8%~10%、10%~20%和20%以上 ...

2009

2.906

0.0

J. Agric. Food Chem.. 2009, 57(20):9754–9763-null

The Forage and Grain of MON 87460, a Drought-Tolerant Corn Hybrid, Are Compositionally Equivalent to That of Conventional Corn

George G. Harrigan * , William P. Ridley , Kathleen D. Miller § , Roy Sorbet , Susan G. Riordan , Margaret A. Nemeth , William Reeves and Todd A. Pester

† Product Safety Center ‡ Regulatory Affairs Monsanto Company, 800 North Lindbergh Boulevard, St. Louis, Missouri 63167 § Covance Laboratories Inc., 3301 Kinsman Boulevard, Madison, Wisconsin 53704 Certus International, Inc., Suite 200, 1422 Elbridge Payne Road, Chesterfield, Missouri 63017 *To whom correspondence should be addressed.

MON 87460 contains a gene that expresses cold shock protein B (CSPB) from Bacillus subtilis . Expression of this gene confers a yield advantage when yield is limited by water availability. Compositional analyses of MON 87460 and a conventional corn variety with similar background genetics were conducted on forage and grain harvested from multiple replicated field sites across the United States during the 2006 growing season and across Chile during the 2006−2007 growing season. The U.S. field trials were conducted under typical agronomic practices, whereas the Chilean field trials incorporated a strip-plot design that included well-watered and water-limited treatments. Results demonstrated that levels of the components analyzed were comparable between MON 87460, the conventional control, and the commercially available corn hybrids.

... 参照Demming-Adams等^[16]方法, 最大光化学效率F_v/F_m= (F_m - F_o)/F_m, 实际量子产量#cod#x003a6 ...

1999

0.0

... 5 耐旱系数DTC Bouslama^[17]提出的耐旱系数=胁迫下的平均单株产量/非胁迫下的平均单株产量 ...

2011

2.474

0.0

. 2011, 124:null-null

Large-scale screening for maize drought resistance using multiple selection criteria evaluated under water-stressed and well-watered environments

... 根据聚类图将参试材料分成耐旱性强的、耐旱性较强的、耐旱性弱的等不同等级^[18] ...

2009

0.0

... 1 玉米自交系吐丝期耐旱性评价指标的选用耐旱系数^[19]可反映植物对干旱的敏感程度 ...

2004

5.242

0.0

... 由于植物的耐旱性是由多种因素相互作用而构成的一个较为复杂的综合性状, 不同指标对耐旱性的贡献也不一样^[20] ...

2006

0.0

0.602

. 2006, 18(1):51-55

The application of chlorophyll fluorescence kinetics in the study of physiological responses of plants to environmental stresses

概述了叶绿素荧光动力学的基本原理和测量方法,以及近年来叶绿素荧光动力学在植物抗逆生理研究中的应用,包括植物对光抑制、低温、热、水分和盐碱、营养、病原菌侵染等各种环境因子胁迫的反应.

... 植物的耐旱机制很复杂, 不同品种其耐旱机制及同一品种在不同环境不同生育时期其耐旱机制都存在差异^[21] ...

... 陈建民等研究认为在干旱条件下玉米叶片的光合作用受抑制, 光合速率下降, 耐旱性较强的品种能维持较高的光合速率, 玉米叶片的叶绿素含量较耐旱性较差的品种下降幅度小^{[21,22,23,24,25,26]} ...

2009

0.0

0.965

. 2009, 17(2):60-63

Effect of water stress on maize yield during different growing stages

不同生育时期水分胁迫的研究结果表明,任何生育时期的土壤干旱均会导致玉米减产,其中抽雄吐丝期水分胁迫减产最重,其次是拔节期,苗期相对较轻.苗期水分胁迫使玉米子粒的"库"形成受到一定阻碍,但由于后期仍维持较大的绿叶面积,复水后可迅速补偿由于前期水分胁迫所减少的生长量,减产较轻.拔节期水分胁迫导致植株矮化,穗位高降低,从而使产量降低.抽雄吐丝期是玉米的水分临界期,干旱可导致散粉至吐丝期间隔(ASI)加大,致使花期不遇,穗粒数大幅度下降,从而严重影响玉米的产量.

... 2 不同耐旱类型玉米自交系的耐旱系数与吐丝期叶片光合参数的相关性作物受到干旱胁迫直接导致产量下降, 而产量主要来源于光合产物的积累, 因此干旱影响着作物的光合作用、呼吸作用、水分和养分的吸收运输等各种生理过程^[22] ...

2012

0.0

1.889

. 2012, 45:1714-1722 DOI:10.3864/j.issn.0578-1752.2012.09.006

Screening and identification of sorghum cultivars for salinity tolerance during germination

1.沈阳农业大学农学院，沈阳 110866 2.沈阳农业大学生物科学技术学院，沈阳 110866

【Objective】The objectives of the current study were to explore the response of different sorghum cultivars to salt stress, screen sorghum cultivars suitable for growing in saline soils, and provide a foundation for management of salt stress.【Method】 Thirty seeds of each of 42 sorghum cultivars were treated with 150 mmol•L-1NaCl or distilled water and incubated in Petri dishes for 10 days at humidity of 60%, light/dark of 12h/12h, illumination of 34 μmol•m-2•s-1 and 28℃/25℃ of day/night. Germination and growth were assessed by counting the number of radicals and coleoptiles and leaves that had appeared on a daily basis from the fourth day and measuring their lengths and dry weights on the tenth day using destructive sampling. The cultivars were classified on the basis of salinity tolerance by means of principal component analysis and cluster analysis considering the range of data on germination and growth traits.【Result】The correlation analysis on the relative values of most germination and growth parameters showed positive relationships among several variables. The cultivars were ranked based on the principal components analysis and five groups on salinity tolerance were sorted for the 42 sorghum cultivars according to the cluster analysis.【Conclusion】Principal component analysis results showed that radical length, coleoptiles and leaf weight and germination rate were the most significant factors and are recommended as the main indexes to identify salinity tolerance of sorghum at germination. The analysis showed five of the 42 cultivars were highly salt tolerant, e.g. Liaoza 15, fourteen cultivars were salt tolerant, e.g. Shenshi 104, twelve cultivars were medium salt sensitive, e.g. Aoza 1, eight cultivars were salt sensitive, e.g Tieza 17, and three were highly salt sensitive, e.g. Longza 10. As this research only relates to ranking sensitivity during germination, further work is needed to determine the mechanism of tolerance and its persistence through the plant life cycle.

【目的】根据不同高粱品种萌发期对盐胁迫的响应，筛选出适合在盐渍土壤上种植的高粱品种及为耐盐胁迫人工调控提供依据。【方法】采用人工气候箱内培养皿培养，用150 mmol•L-1NaCl对42个高粱品种进行胁迫处理，蒸馏水处理为对照，每培养皿放30粒种子。人工气候箱内湿度60%，光照/黑暗时间为12h/12h，光照强度为134 μmol•m-2•s-1，昼/夜温度为28℃/25℃。培养第4天测定发芽势，第10天测定发芽率、根长、叶长、根重、叶重。通过主成分分析、聚类分析和对各品种的表现综合评定，对高粱品种进行耐盐性强弱的分类。【结果】多项萌发和生长参数的相对值之间存在着极显著或显著的正相关。主成分分析结果表明，根长、叶重和发芽率分别在根部、叶部和萌发因子中的负荷量最大，可作为萌发期高粱耐盐性筛选的主要鉴定指标。42个高粱品种的耐盐性存在很大差异，其中辽杂15等5个品种为高度耐盐品种，沈试104等14个品种为耐盐品种，敖杂1等12个品种为中等耐盐品种，铁杂17等8个品种为盐敏感品种，龙杂10等3个品种为高度盐敏感品种。【结论】150 mmol•L-1NaCl可作为高粱萌发期耐盐性鉴定的适宜盐浓度，根长、叶重和发芽率等指标可用于大批量高粱品种耐盐性的评价。

... 光合作用是植株生长的生理基础, 可以反映植株的耐旱性^[23] ...

2006

1.925

0.0

. 2006, 20:689-700 DOI:10.1007/s00468-006-0084-0

Comparative ecophysiological effects of drought on seedlings of the Mediterranean water-saver Pinus halepensis and water-spenders Quercus coccifera and Quercus ilex

1.Universidad Pública de Navarra Departamento de Ciencias del Medio Natural E-31006 Pamplona Spain 2.The University of Western Australia School of Plant Biology 35 Stirling Highway Crawley 6009 Western Australia Australia

Ecophysiological and structural traits of seedlings of the water-saver Pinus halepensis and the water-spenders Quercus coccifera and Q. ilex were studied in response to water stress under greenhouse conditions. Water deficit reduced stomatal conductance ( g s ) and, as a consequence, both net CO 2 assimilation ( A ) and transpiration rate ( E ) were also reduced. Water stress also emphasized midday down-regulation of the photochemical efficiency (dynamic photoinhibition) reducing quantum yield of noncyclic electron transport (Φ PSII ), photochemical quenching (qP) and photochemical efficiency of the open reaction centres of PSII ( F v ￠ / F m ￠ F_{\rm v} ^\prime /F_{\rm m} ^\prime ) and involved an increase of thermal dissipation of excess energy. However, water stress not only induced dynamic photoinhibition but also brought a reduction in F v / F m (chronic photoinhibition). Despite the water-saving strategy of P. halepensis that limited net CO 2 assimilation, this species showed a higher photochemical efficiency and lower photoinhibition than Quercus species. This was not the result of a different photochemical quenching but was linked to a higher value of F v ￠ / F m ￠ F_{\rm v} ^\prime /F_{\rm m} ^\prime , indicating a less severe photo-inactivation of PSII. Water stress resulted in a loss of pigment content and in an increase of the carotenoids/chlorophyll ratio, antioxidant capacity and the biomass rate allocated to roots as opposed to that assigned to leaves. P. halepensis showed a lower photoinhibition and antioxidant activity than Quercus species due to its lower pigment content and higher proportion of carotenoids allowing P. halepensis to use, in a more effective way, the lesser excess energy absorbed.

... 前人研究表明, 在吐丝期干旱胁迫下气孔导度下降, 使光合速率和蒸腾速率都下降, 蒸腾作用降低的程度比光合作用降低的程度大, 利于水分利用效率的提高^[24,25] ...

2012

0.0

1.742

. 2012, 23:1277-1285

Drought resistance evaluation system for backcross lines of Dongxiang common wild rice (Oryza rufipogon Griff.)

( 1 Jiangxi Agricultural University, Nanchang 330045, China;  2 College of Life Sciences, Jiangxi Normal University, Nanchang 330022, China)

A total of 79 rice materials containing Dongxiang wild rice ( Oryza rufipogon Griff.) backcross lines (Dwr)/Xie-qingzao B (Xqz B)//Xqz B and their parents were chosen as the test objects to study the relationships between the drought resistance of these materials and the 31 drought resistance indices at germinating stage, seedling stage, booting stage, and mature stage. The results showed that the drought resistance index or the drought resistance coefficient of these materials were significantly correlated to the relative germination energy (RGE) under 15% PEG6000 drought stress, the germination drought resistance index (GDRI) and relative germination energy (RGE) under 20% PEG6000 drought stress, and the relative value of maximum root length (MRL), seeding height (SH), fresh root mass (FRM), dry root mass (DRM), root relative water content (RRWC), wilting rate (WR), leaf soluble sugar content (LSSC), leaf proline content (LPC), leaf MDA content (LMDAC), leaf relative water content (LRWC), level of rolling leaf (RL), plant height (PH), tiller number per plant (TNP), productive tiller number per plant (PTNP), filled spikelets per panicle (FSP), panicle density (PD), seed setting rate (SR), and 1000-grain mass (TGM) under water stress. Through stepwise regression analysis, nine drought resistance indices including the RGE under 20% PEG-6000 drought stress and the relative values of DRM, RRWC, LSSC, LPC, LMDAC, ETNP, SR, and TGM under water stress were selected. Base on these indices and their partial correlation coefficients, the drought resistance evaluation equation ( D value) and evaluation system were established, which could well assess the drought resistance of the Dongxiang common wild rice backcross lines at different growth stages.

选用协青早B//东乡野生稻/协青早B回交重组系及其亲本共79份水稻材料，研究了水稻发芽期、苗期、孕穗期、成熟期的种子萌发抗旱指数等31个指标与东乡野生稻回交重组系抗旱性的关系.结果表明： 15% PEG-6000溶液处理的相对发芽势、20%PEG-6000溶液处理的种子萌发抗旱指数和相对发芽势及水分胁迫后最长根长、苗高、根鲜质量、根干质量、根系相对含水量、萎蔫率、叶片可溶性糖含量、叶片脯氨酸含量、叶片丙二醛含量、叶片相对含水量、卷叶级别、株高、单株分蘖数、单株有效穗数、穗实粒数、着粒密度、结实率、千粒重等21个指标的相对值与抗旱系数或抗旱指数的相关性显著.通过逐步回归分析筛选出9个抗旱性鉴定指标：20% PEG-6000溶液处理的相对发芽势及水分胁迫后根干质量、根系相对含水量、叶片可溶性糖含量、叶片脯氨酸含量、叶片丙二醛含量、单株有效穗、结实率和千粒重的相对值.根据这些指标和偏相关系数，建立了不同时期的抗旱性评价( D 值)方程和评价体系，可对东乡野生稻回交重组系抗旱性进行较好的评价.

2000

0.0

1984

1.513

0.0

... 相关性分析表明, 在干旱处理中, 叶绿素含量的降幅与品种耐旱性显著相关^[27] ...

1989

0.0

0.661

... 3 不同耐旱类型玉米自交系吐丝期耐旱相关光合参数阈值范围多种作物上的耐旱性研究表明, 作物耐旱性受多种因素影响, 以单一指标评价玉米自交系吐丝期的耐旱能力具有一定的片面性, 而多指标评价又过于繁琐和低效^[28,29] ...

2012

0.0

. 2012, 871:31-39

Design and Construction of Recombinant Inbred Lines

Daniel A. Pollard (1)

1. Division of Biology, University of California, San Diego, La Jolla, CA, 92093, USA

Recombinant inbred lines (RILs) are a collection of strains that can be used to map quantitative trait loci. Parent strains are crossed to create recombinants that are then inbred to isogenicity, resulting in a permanent resource for trait mapping and analysis. Here I describe the process of designing and constructing RILs. This consists of the following steps. Parent strains are selected based on phenotype, marker availability, and compatibility, and they may be genetically engineered to remove unwanted variation or to introduce reporters. A construction design scheme is determined, including the target population size, if and how advanced intercrossing will be done, and the number of generations of inbreeding. Parent crosses and F1 crosses are performed to create an F2 population. Depending on design, advanced intercrossing may be implemented to increase mapping resolution through the accumulation of additional meiotic crossover events. Finally, lines are inbred to create genetically stable recombinant lines. I discuss tips and techniques for maximizing mapping power and resolution and minimizing resource investment for each stage of the process.