Growth and Photosynthesis Responses of a Super Dwarf Rice Genotype to Shade and Nitrogen Supply  

作　　者：Marc SCHMIERER Oliver KNOPF Folkard ASCH 

机构地区：[1]Institute of Agricultural Sciences in the Tropics,University of Hohenheim,Stuttgart 70599,Germany [2]Institute for Bio-and Geo-Sciences,IBG-2:Plant Sciences,Forschungszentrum Jülich GmbH,Jülich 52428,Germany

出　　处：《Rice science》2021年第2期178-190,共13页水稻科学（英文版）

摘　　要：Specific aspects of plant cultivation require tests under fully controlled environmentalconditions with restricted energy supply, such as orbit-based space laboratories and low-light conditions.For these growing conditions, super dwarf plants have been developed as model crops, and a gibberellindeficientSuper Dwarf Rice genotype was proposed as a model crop for space flight plant experiments.We tested this genotype in a climate chamber experiment under different illumination and nitrogen supplylevels to assess its suitability under scenarios with limited resource availability. A 25% reduction inillumination led to a 75% reduction in yield, mainly due to a 60% reduction in formed tillers and 20%reduction in grain weight, and a 80% reduction in illumination caused total yield loss. Leaf area underreduced illumination was significantly lower, and only marginal changes in the dimensions of leaves wereobserved. Plant photosynthesis was not significantly different between control and 75% illumination. Thiswas explained by a higher photochemical efficiency under lower light conditions and a reduced mesophyllresistance. Therefore, we concluded that this genotype is well-suited for plant experiments under spaceand light-limited conditions since it kept its small stature and showed no shade avoidance mechanisms,such as leaf elongation, which would complicate experiments under low-light conditions. Nitrogenconcentrations of 2.8 and 1.4 mmol/L led to no differences in plant growth. We concluded that a nitrogenconcentration of 1.4 mmol/L is sufficient for this genotype under the light intensities.

关 键 词：super dwarf rice photosynthetic limitation analysis SHADE nitrogen 

分 类 号：S511[农业科学—作物学]