Agronomic evaluation of shade tolerance of 16 spring Camelina sativa (L.) Crantz genotypes under different artificial shade levels using a modified membership function

Abstract

Camelina [Camelina sativa (L.) Crantz] is currently gaining considerable attention as a potential oilseed feedstock for biofuel, oil and feed source, and bioproducts. Studies have shown the potential of using camelina in an intercropping system. However, there are no camelina genotypes evaluated or bred for shade tolerance. The objective of this study was to evaluate and determine the shade tolerance of sixteen spring camelina genotypes (growth stage: BBCH 103; the plants with 4–5 leaves) for intercropping systems. In this study, we simulated three different shade levels, including low (LST), medium (MST), and high shade treatments (HST; 15, 25, and 50% reduction of natural light intensity, respectively), and evaluated the photosynthetic and physiological parameters, seed production, and seed quality. The mean chlorophyll pigments, including the total chlorophyll and chlorophyll a and b across the 16 genotypes increased as shade level increased, while the chlorophyll fluorescence parameter Fv/Fm, chlorophyll a/b, leaf area, the number of silicles and branches plant−1 decreased as shade level increased. The first day of anthesis and days of flowering duration of camelina treated with shade were significantly delayed and shortened, respectively, as shade increased. The shortened lifecycle and altered flowering phenology decreased camelina seed yield. Additionally, the shade under MST and HST reduced the seed oil content and unsaturated fatty acids, but not saturated fatty acids. The dendrograms constructed using the comprehensive tolerance membership values revealed that CamK9, CamC4, and ‘SO-40’ were the relatively shade-tolerant genotypes among the 16 camelina genotypes. These camelina genotypes can grow under the shade level up to a 25% reduction in natural light intensity producing a similar seed yield and seed oil quality, indicating the potential to intercrop with maize or other small grain crops. The present study provided the baseline information on the response of camelina genotypes to different shade levels, which would help in selecting or breeding shade-tolerant genotypes.

Evaluation of different bermudagrass germplasm at physiological and molecular level under shade along longitudinal and latitudinal gradients

“…Specifically, bermudagrass experiences a significant reduction in chlorophyll a (Chl a ) content and no significant effect on Chl a/b ratio, while the total chlorophyll and Chl b contents increased in our study. This is primarily due to the acceleration in chlorophyll a conversion to chlorophyll b in bermudagrass leaves in shaded environments, which results in a high increase rate in chlorophyll b as compared to chlorophyll a, subsequently decreases the ratio of chlorophyll a/b [ 51 ]. On the other hand, HEMA (glutamyl-tRNA reductase) is an indispensable gene that plays a key role in initiating chlorophyll production.…”

Evaluation of the Aluminum (Al3+) Tolerance of Camelina and the Potential for Using Melatonin or Nano-Selenium to Alleviate Al3+-Induced Stress in Camelina

“…In this study, sixteen camelina genotypes used in our previous studies [35] were tested. The detailed information concerning the camelina genotypes, accession number, seed origin, and seed accessibility is described in Supplementary Table S1.…”

“…The plants were harvested at maturity (about 4 months' cultivation) (BBCH 89) and accessed accordingly. The oil content of seeds resulted from each treatment was determined following the Soxhlet extraction method [35]. The oil fatty acid composition and concentration were analyzed by gas chromatography (GC) (GC9800, Shanghai Kechuang Chromatographic Instrument Co., Ltd., Shanghai, China) (flame ionization detector) fitted with a HP-88 capillary column (0.25 mm × 100 m × 0.2 µm, J & W, Folsom, CA, USA).…”

“…The oil fatty acid composition and concentration were analyzed by gas chromatography (GC) (GC9800, Shanghai Kechuang Chromatographic Instrument Co., Ltd., Shanghai, China) (flame ionization detector) fitted with a HP-88 capillary column (0.25 mm × 100 m × 0.2 µm, J & W, Folsom, CA, USA). Detailed information, such as that regarding the GC conditions and fatty acid methyl esters (FAMEs) sorting, was described in our previous study [35]. All the evaluations were carried out at the Laboratory of Grass Germplasm Resources Research and Utilization, Yangzhou University, China.…”

Exogenous Application of Multi-Walled Carbon Nanotubes (MWCNTs) and Nano-Selenium (Nano-Se) Alleviated the PEG-Induced Water Deficit Stress and Improved the Crop Performance of Camelina

“…The fatty acid composition was analyzed by gas chromatography (GC) at the Laboratory of Animal Nutrition and Feed Engineering Technology Research, Yangzhou University, China. The detailed information on sample preparation, GC conditions, fatty acid methyl esters (FAMEs) sorting, and determination of the seed quality parameters were described in a previous study [32].…”