Assessment of differences in morphological and physiological leaf lodging characteristics between two cultivars of Hippeastrum rutilum

Abstract

Background Environmental lodging stress, which is a result of numerous factors, is characterized by uncertainty. However, several studies related to lodging in cereal crops have reported that lodging in the Hippeastrum rutilum environment is very rare. Hippeastrum rutilum is a garden flower with high ornamental value and abundant germplasm resources. Under past cultivation practices, it was found that the plant types of ‘Red Lion’, with red flowers, and ‘Apple Blossom’, with pink flowers, are quite different. The leaves of ‘Red Lion’ are upright, while the leaves of ‘Apple Blossom’ show lodging, which seriously affects its ornamental value. The aims of this study were to compare the differences between the two varieties with leaf lodging and upright leaves according to morphological and physiological attributes. In this study, karyotype analysis and phenotypic morphological and physiological characteristics were compared to explore the differences between the two plant types. Results The karyotype analysis of the two cultivars showed that their chromosome types were both tetraploid plants. The results showed that the lignin content in the leaves of ‘Red Lion’ was high, the cross-sectional structure of the leaf vascular bundle was more stable, and the chlorophyll content was high. In addition, significantly less energy was transferred to the electron transport chain (ETR) during the photoreaction. Similarly, the results regarding the maximum photosynthetic rate (Fv/Fm), nonphotochemical quenching (NPQ) and effective quantum yield of photosystem II photochemistry (△F/Fm′) all indicated that the photosynthetic capacity of “Red Lion” was greater than that of “Apple Blossom”, which was affected by leaf lodging. The size of the leaves was significantly smaller, and the leaf sag angle, leaf width, and leaf tip angle presented significantly lower values in ‘Red Lion’ than in ‘Apple Blossom’, which exhibits leaf sag. The difference in these factors may be the reason for the different phenotypes of the two cultivars. Conclusion The results of this study proved that lodging affects the photosynthetic capacity of Hippeastrum rutilum and revealed some indexes that might be related to leaf lodging, laying a theoretical foundation for cultivating and improving new varieties.

Morphology, photosynthetic and molecular mechanisms associated with powdery mildew resistance in Kentucky bluegrass

“…Plant saturation pulse light frequency was set to 20 s /times, the intensity to 4000 μmol m −2 s −1 , and the light intensity for actinic light parameters to 86 μmol m −2 s −1 . The plant samples were placed in darkness for 20 min; and then minimum fluorescence (Fo) and maximum fluorescence (Fm) of the samples were recorded by using the measuring light and saturated pulsed light, respectively (Shi et al, 2020). The value and image of NPQ (non‐photochemical quenching), Y(II) (actual photochemical efficiency), Y(NO) (non‐adjusting energy dissipation yield), qP (photochemical quenching), and electron quantum transport rate (ETR) were obtained through actinic light measurements.…”

Identification of Golovinomyces artemisiae Causing Powdery Mildew, Changes in Chlorophyll Fluorescence Parameters, and Antioxidant Levels in Artemisia selengensis

“…Chlorophyll fluorescence parameters of GI and CK were measured using the Imagining-PAM (MAXI) system (Walz, Germany). The value (Ft) of the selected sample in area of interest (AOI) was set within the range of 0.1-0.2, plant saturation pulse light frequency was set to 20 s/times and the intensity was set to 4,000 µmol m −2 s −1 , and the light intensity for actinic light parameters was set to 86 µmol m −2 s −1 (Shi et al, 2020). The plant samples were treated in darkness for 20 min; minimum fluorescence (Fo) and maximum fluorescence (Fm) of the samples were obtained using the measuring light and saturated pulsed light, respectively.…”