[Objective] The paper was to study the effect of chemical-controlled topping technology on spectral and photosynthetic characteristics of cotton. [Method] Two row spacing configurations and four topping treatments wer...[Objective] The paper was to study the effect of chemical-controlled topping technology on spectral and photosynthetic characteristics of cotton. [Method] Two row spacing configurations and four topping treatments were set in the experiment field, and the spectral and photosynthetic characteristics of cotton under different configurations and topping treatments were analyzed. [Result] There was no significant difference in spectral reflectance of cotton leaves and canopy among all treatments(T1-T8) before topping. After topping, the spectral reflectance of cotton leaves showed little difference in visible light band, but significant differences in near-infrared light band under two row spacing configurations(T2-T4, T6-T8).And in near-infrared band, compared with CK(T1, T5), the reflectance increased and then decreased under close planting with equal row spacing configurations(T2-T4) and narrow row dense planting configurations(T6-T8). However, the change of cotton canopy reflectance in short infrared bands increased first and then decreased under close planting with equal row spacing configuration, and increased constantly under narrow row dense planting configuration. The photosynthetic capacity of leaves increased, and the net photosynthetic rate(A), stomatal conductance(GH_(2O)),transpirationrate(E) and intercellular CO_(2) concentration(Ci) significantly increased by controlling the top with chemicals, and differences were ob-served between two configurations. After topping treatments, the leaf area of apical leaf increased, and chemical-controlled topping treatments had significant difference with the control. The apical cotton leaves were shrunk internally, and the plant height increased gradually by 7-15 cm;the number of fruit branches increased by 2-4, and the area of apical leaves decreased significantly in chemical-controlled topping treatments.[Conclusion] After topping with chemicals, the spectral characteristics of cotton change, the photosynthetic capacity of leaves is improved, and the growth of apical leaves and apex of cotton is inhibited.展开更多
基金Supported by National Natural Science Foundation of China (41961054)Second Level Project of Xinjiang Corps Talents & Leading Talents Project of Xinjiang Production and Construction Corps(2019CB018)。
文摘[Objective] The paper was to study the effect of chemical-controlled topping technology on spectral and photosynthetic characteristics of cotton. [Method] Two row spacing configurations and four topping treatments were set in the experiment field, and the spectral and photosynthetic characteristics of cotton under different configurations and topping treatments were analyzed. [Result] There was no significant difference in spectral reflectance of cotton leaves and canopy among all treatments(T1-T8) before topping. After topping, the spectral reflectance of cotton leaves showed little difference in visible light band, but significant differences in near-infrared light band under two row spacing configurations(T2-T4, T6-T8).And in near-infrared band, compared with CK(T1, T5), the reflectance increased and then decreased under close planting with equal row spacing configurations(T2-T4) and narrow row dense planting configurations(T6-T8). However, the change of cotton canopy reflectance in short infrared bands increased first and then decreased under close planting with equal row spacing configuration, and increased constantly under narrow row dense planting configuration. The photosynthetic capacity of leaves increased, and the net photosynthetic rate(A), stomatal conductance(GH_(2O)),transpirationrate(E) and intercellular CO_(2) concentration(Ci) significantly increased by controlling the top with chemicals, and differences were ob-served between two configurations. After topping treatments, the leaf area of apical leaf increased, and chemical-controlled topping treatments had significant difference with the control. The apical cotton leaves were shrunk internally, and the plant height increased gradually by 7-15 cm;the number of fruit branches increased by 2-4, and the area of apical leaves decreased significantly in chemical-controlled topping treatments.[Conclusion] After topping with chemicals, the spectral characteristics of cotton change, the photosynthetic capacity of leaves is improved, and the growth of apical leaves and apex of cotton is inhibited.
