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Acta Agronomica Sinica ›› 2018, Vol. 44 ›› Issue (8): 1205-1211.doi: 10.3724/SP.J.1006.2018.01205

• TILLAGE & CULTIVATION · PHYSIOLOGY & BIOCHEMISTRY • Previous Articles     Next Articles

Effects of Water Deficit at Flowering Stage on Yield and Quality of Fresh Waxy Maize

Long-Jian SHI(),Zhang-Rong WEN,Shi-Bo ZHANG,Jue WANG,Wei-Ping LU,Da-Lei LU()   

  1. Jiangsu Key Laboratory of Crop Genetics and Physiology / Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, Jiangsu, China
  • Received:2018-02-04 Accepted:2018-06-12 Online:2018-08-10 Published:2018-06-19
  • Contact: Da-Lei LU E-mail:412950386@qq.com;dllu@yzu.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(31471436);the National Natural Science Foundation of China(31771709);the National Natural Science Foundation of China(31271640);the National Key Research and Development Program of China(2016YFD0300109);the Technology System of Modern Agriculture Industry in Jiangsu Province(SXGC[2017]307);the Qing Lan Project of Jiangsu Province, and the Priority Academic Program Development of Jiangsu Higher Education Institutions.

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Abstract:

In order to clarify the influence of water deficit at flowering stage (tasseling silking stage) on yield and quality of fresh waxy maize (harvest at 23 d after silking), the fresh ear/grain yield and kernel components, pasting and thermal properties were measured using Suyunuo 5 and Yunuo 7. The soil moisture content was controlled by negative-pressure water supply and controlling pot device, and the relative soil moisture content for control and drought treatments was 80% and 60%, respectively. The drought at flowering stage decreased grain number, weight and volume, leading to the yield loss of fresh ear and grain. Under water deficit condition, grain starch content was increased, while protein content was increased in Yunuo 7 and unchanged in Suyunuo 5. For protein components, globulin contents was not affected by drought, while albumin, zein and glutenin contents were decreased when plants suffered water deficit at flowering stage. The starch granule size was reduced by drought for both varieties in both years, while starch iodine binding capacity for both varieties was decreased in 2015 and not affected in 2014 by drought. The peak, trough and final viscosities of grains were increased in Yunuo 7 and decreased in Suyunuo 5. Under drought condition, the grain peak gelatinization temperatures were decreased, retrogradation enthalpy and percentage were increased, while gelatinization enthalpy was only increased in Yunuo 7 in 2014. In conclusion, drought at flowering stage decreases fresh ear/grain yield, increases grain starch content, decreases protein content, starch granule size and the proportion of long chains in amylopectin, and increases the grain retrograde, while viscosities in response to water deficit are dependent on varieties (increases in Yunuo 7 and decreases in Suyunuo 5).

Key words: fresh waxy maize, water deficit at flowering stage, yield, quality

Table 1

Effects of drought at flowering stage on yield of fresh waxy maize"

品种
Variety		 处理
Treatment		 鲜籽粒重Fresh grain weight (mg) 干籽粒重
Dry grain weight (mg)		 鲜籽粒体积
Fresh grain volume (μL)		 每穗粒数
Grain
number		 鲜果穗产量
Fresh ear yield
(g plant-1)		 鲜籽粒产量
Fresh grain yield
(g plant-1)		 籽粒含水率
Grain moisture content (%)
2014
苏玉糯5号
Suyunuo 5		 对照Control 241.4 d 97.8 d 230.0 c 490.0 ab 158.0 c 118.2 cd 59.5 c
干旱Drought 241.6 d 94.6 de 216.7 d 438.7 bc 142.9 d 105.9 d 60.8 b
渝糯7号
Yunuo 7		 对照Control 276.4 b 97.1 d 260.0 b 490.0 ab 178.9 b 135.5 b 64.9 a
干旱Drought 258.4 c 90.3 e 250.0 b 443.3 bc 159.6 c 114.6 cd 65.1 a
2015
苏玉糯5号
Suyunuo 5		 对照Control 285.4 b 122.7 b 260.0 b 428.7 c 160.6 c 122.3 bc 57.0 e
干旱Drought 249.9 cd 108.0 c 226.7 cd 345.3 d 136.2 d 86.3 e 56.8 e
渝糯7号
Yunuo 7		 对照Control 322.1 a 133.7 a 273.3 a 521.3 a 230.7 a 167.9 a 58.5 d
干旱Drought 279.7 b 111.9 c 253.3 b 455.3 bc 171.8 bc 127.3 bc 60.0 c

Table 2

Effects of drought at flowering stage on grain protein and starch contents of fresh waxy maize (mg g-1)"

品种
Variety		 处理
Treatment		 清蛋白
Albumin		 球蛋白Globulin 谷蛋白
Zein		 醇溶蛋白
Glutenin		 蛋白质
Protein		 淀粉
Starch
2014
苏玉糯5号
Suyunuo 5		 对照Control 12.9 a 4.8 ab 25.9 a 21.0 b 90.7 a 550.9 d
干旱Drought 10.1 d 5.4 a 21.3 b 18.2 c 89.9 a 621.9 b
渝糯7号
Yunuo 7		 对照Control 11.5 b 4.5 b 18.7 cd 24.5 a 79.0 b 571.8 cd
干旱Drought 10.4 d 4.7 ab 15.7 e 23.8 a 67.9 e 646.7 a
2015
苏玉糯5号
Suyunuo 5		 对照Control 12.7 a 1.8 c 16.3 de 12.5 e 77.6 bc 559.5 d
干旱Drought 12.6 a 1.9 c 14.2 ef 11.1 ef 76.6 cd 581.8 cd
渝糯7号
Yunuo 7		 对照Control 12.7 a 2.1 c 19.8 bc 14.1 d 75.3 d 562.5 cd
干旱Drought 11.0 c 2.1 c 12.8 f 10.4 f 68.8 e 604.4 bc

Fig. 1

Effects of drought at flowering stage on starch granule volume distribution of fresh waxy maize"

Fig. 2

Effects of drought at flowering stage on grain starch maximum absorption wavelength and iodine binding capacity of fresh waxy maize"

Table 3

Effects of drought at flowering stage on grain pasting property of fresh waxy maize"

品种
Variety		 处理
Treatment		 峰值黏度
PV (cP)		 谷值黏度
TV (cP)		 崩解值
BD (cP)		 终值黏度
FV (cP)		 回复值
SB (cP)		 糊化温度
Ptemp (°C)
2014
苏玉糯5号
Suyunuo 5		 对照Control 569 e 555 e 14 e 829 e 275 b 77.3 bc
干旱Drought 482 f 472 f 10 e 672 f 201 cd 78.1 ab
渝糯7号
Yunuo 7		 对照Control 769 d 708 d 61 d 975 cd 267 b 76.9 c
干旱Drought 1188 b 982 a 207 b 1438 a 457 a 75.0 d
2015
苏玉糯5号
Suyunuo 5		 对照Control 764 d 711 d 53 d 938 d 227 c 77.9 ab
干旱Drought 744 d 687 d 57 d 864 e 177 d 78.8 a
渝糯7号
Yunuo 7		 对照Control 913 c 809 c 104 c 1007 c 198 cd 78.7 a
干旱Drought 1306 a 923 b 383 a 1112 b 189 d 77.5 bc

Table 4

Effects of drought at flowering stage on grain thermal property of fresh waxy maize"

品种
Variety		 处理
Treatment		 热焓值
ΔHgel (J g-1)		 起始温度
To (°C)		 峰值温度
Tp (°C)		 终值温度
Tc (°C)		 回生热焓值
ΔHret (J g-1)		 回生值
%R (%)
2014
苏玉糯5号
Suyunuo 5		 对照Control 9.6 ab 73.4 a 78.1 a 84.5 a 2.5 b 26.5 c
干旱Drought 9.6 ab 73.1 b 77.6 b 83.6 bc 3.2 a 33.9 a
渝糯7号
Yunuo 7		 对照Control 8.8 b 72.9 c 77.6 b 84.4 a 1.8 c 20.6 d
干旱Drought 10.3 a 72.8 c 77.2 c 83.3 c 3.1 ab 29.9 bc
2015
苏玉糯5号
Suyunuo 5		 对照Control 10.0 a 72.8 c 77.9 a 84.1 ab 3.3 a 32.7 ab
干旱Drought 10.3 a 72.4 d 77.0 c 83.8 bc 3.5 a 34.5 a
渝糯7号
Yunuo 7		 对照Control 9.6 ab 71.2 e 75.9 d 82.1 d 3.1 ab 32.2 ab
干旱Drought 9.4 ab 71.1 e 75.6 e 82.4 d 3.3 a 35.3 a
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