高温热害对大豆农艺性状和产量的影响及其灰色关联度分析

Effects of High Temperature and Heat Damage on Agronomic Traits and Yield of Soybean and Its Grey Correlation Analysis

由于全球性气温上升,夏季高温极端天气频发,热害成为影响我国大豆生产的主要因素之一。河南省漯河市2019年6~9月气温较历年增高13.3℃,其中7月中旬至8月中旬(大豆开花结荚期)气温远远高于大豆要求的最适温度(20~28℃),气温超过33℃的高温天气达到30 d;2020年7月中下旬平均气温25℃左右,有利于大豆开花结荚。本研究以2019~2020年漯河市农业科学院承担的黄淮海联合体(南片)试验的8个大豆品种为试验材料,以气温正常年份(2020年)的试验数据为对照,对2019年高温热害条件下大豆农艺性状和产量的变化进行了分析;并采用灰色关联度分析方法,对热害条件下大豆农艺性状变化幅度与产量降幅的关联度进行分析,以筛选评价大豆是否受到热害的主要指标。结果表明:热害胁迫后,大部分品种株高、主茎节数、有效荚数、单株粒数和单株粒重显著降低,有效分枝数显著增多,百粒重维持在较高水平,产量明显降低。不同品种对热害的反应程度不同,说明大豆对热害存在一定抗性,但不同品种的抗热性具有一定差异。大豆受热害后,各农艺性状指标值增减幅度与产量降幅的关联度顺序为株高>有效荚数>百粒重>主茎节数>单株粒数>单株粒重>有效分枝数>底荚高,其中株高、有效荚数、百粒重和主茎节数与产量的关联度均达到0.72以上,对大豆产量影响较大,可以作为判断大豆是否受到热害的重要指标。

Due to the rising global temperature and frequent high temperature and extreme weather in summer,heat damage has become one of the main factors affecting soybean production in China.The temperature from June to September 2019 in Luohe,Henan Province,was 13.3℃higher than that of previous years,of which the temperature from mid-July to mid-August(the flowering and podding period of soybean)was far higher than the optimum temperature required for soybean(20-28℃),and the high temperature weather with tem perature above 33℃reached 30 days.The average temperature in the middle and late July 2020 was about 25℃,which was conducive to the flowering and podding of soybean.The changes of agronomic traits and yield of soybean under the condition of high temperature and heat damage in 2019 were analyzed with 8 soybean varieties in Huanghuaihai Joint Venture(South)experiment undertaken by Luohe Academy of Agricultural Sciences from 2019 to 2020 as the test materials and the test data in the normal year(2020)as the control.The grey correlation degree analysis method was used to analyze the correlation degree between the change range of soybean agronomic traits and the yield reduction under the condition of heat damage,so as to screen the main indicators for evaluating whether the soybean was affected by heat damage.The results showed that the plant height,the number of main stem nodes,the number of effective pods,the number of grains per plant and the weight of grains per plant of most varieties significantly decreased,the number of effective branches significantly increased,the weight of 100-grain was maintained at a high level,and the yield significantly decreased after heat stress. Different varieties had different responses to heat damage,which indicated that soybean had certain resistance to heat damage,but different varieties had certaindifferences in heat resistance. After the soybean was damaged by heat,the correlation degree between the increase and decrease of each agronomic trait index value and the yield reduction was in the order of plantheight>number of effective pods>100-grain weight>number of main stem nodes>number of grains per plant>number of effective branches per plant>height of bottom pods. The correlation degree of plant height,numberof effective pods,100 -grain weight and number of main stem nodes with the yield was more than 0.72,which had a great impact on the soybean yield and could be used as an important indicator to judge whetherthe soybean was damaged by heat.