不同施氮水平辣椒单叶光谱特征及SPAD值与叶绿素含量的相关性

Correlations between Single Leaf Spectral Characteristics,SPAD Value and Chlorophyll Content in Pepper under Different Nitrogen Levels

为及时、准确无损地估测辣椒叶绿素含量,获取辣椒长势,通过田间试验,分析2个辣椒品种不同氮肥水平下辣椒单叶反射光谱、SPAD值与叶绿素含量的相关性。结果表明:果实膨大期和盛果期叶绿素含量的特征波段长辣6号为680和2026 nm,火焰山为360和1349 nm,特征波段下光谱反射率与叶绿素含量之间的相关系数|r|分别为0.961、0.994、0.891和0.678(P<0.01)。不同品种辣椒叶片SPAD值与叶绿素含量(叶绿素a、叶绿素b、叶绿素总量)间存在正相关关系,相关性强弱均表现为长辣6号>火焰山。SPAD值与叶绿素a、叶绿素b和叶绿素总量之间的相关系数长辣6号为0.66、0.69和0.68(P<0.01),火焰山为0.39、0.36和0.41(P<0.05)。

The correlations between single leaf reflection spectrum, SPAD value and chlorophyll content in two pepper varieties under different nitrogen levels were studied by a field trial to estimate chlorophyll content and growth vigor of pepper timely, accurately and nondestructively. Results：the chlorophyll content＇ special band of Changla 6 and Huoyanshan varieties at fruit expanding stage and full fruit stage is 680 and 2026 nm, 360 and 1349 nm respectively. The correlation coefficient between spectral reflectance and chlorophyll content is 0. 961, 0. 994, 0.891 and 0. 678 （ P 〈 0.01 ） under special bands respectively. There are the positive correlations between leaf SPAD value and chlorophyll content （chlorophyll a, chlorophyll b and total chlorophyll） in two pepper varieties and the correlation degree in Changla 6 is higher than Huoyanshan. The correlation coefficient between SPAD and chlorophyll a, chlorophyll b, total chlorophyll is 0.66, 0.69 and 0.68 （ P 〈 0.01 ） in Changla 6 but the correlation coefficient between SPAD and chlorophyll.a, chlorophyll b, total chlorophyll is 0.39,0.36 and 0. 41 ＊ （P 〈0.05）in Huoyanshan respectively.