Effect Of Chromosome On Low Phosphorus Stress And Its Recovery In Nullisomic-tetrasomic Chinese Spring Wheat

As macro-nutrition elements,phosphorus plays an important role in the production of wheat and the phosphorus utilization efficiency in wheat is mainly controlled by quantitative characteristics,which genetic mechanism is very complex.Screening phosphorus utilization efficiency in wheat germplasm can lay a material foundation for improving phosphorus utilization efficiency of wheat varieties.Six nullisomic-tetrasomic chinese spring wheat were included in this study to investigate phosphorus absorption,distribution,photosynthetic physiological response and the change of antioxidant protective enzymes in order to clarify the physiological effects of different chromosomes on phosphorus utilization efficiency under low phosphorus stress and its recovery,which provided scientific guidance for breeding wheat varieties with high phosphorus efficient.The main results are as follows:(1)Low phosphorus stress significantly reduced plant height,leaf area,specific leaf weight and biomass of N7D-T3 B,N7A-T3 D,N3A-T7 B,N7D-T1 A,N7B-T2 D and N7D-T2 A,among which N3A-T7 B decreased the least.Low phosphorus stress promoted root development of N7D-T3 B,N7A-T3 D,N3A-T7 B and N7D-T1 A,and inhibited root development of N7B-T2 D and N7D-T2 A.Compared with the normal phosphorus treatment,the supply of phosphorous recovery significantly increased the plant height,biomass,specific leaf weight and leaf area of N3A-T7 B,while significantly reduced the plant height and aboveground biomass accumulation of other wheat materials.(2)Low phosphorus stress significantly inhibited the accumulation of calcium,iron and magnesium in wheat and increased the accumulation of zinc and manganese,among which N3A-T7 B showed the smallest decrease and the largest increase.At the same time,low phosphorus stress significantly inhibited the above ground phosphorus content of N3A-T7 B,but there was no significant difference in the underground phosphorus content,while the phosphorus content of other wheat materials was inhibited.In terms of phosphorus utilization efficiency and photosynthetic phosphorus utilization efficiency,low phosphorus stress increased its efficiency significantly.Under the conditions of multiple phosphorus supply,compared with the low phosphorus stress,the absorption and accumulation of calcium,iron,magnesium and aboveground phosphorus elements were alleviated,and the content of manganese and zinc,phosphorus utilization efficiency and photosynthetic phosphorus utilization efficiency were significantly reduced.(3)Low phosphorus stress reduced the chlorophyll content,net photosynthetic rate and photosystem II quantum efficiency of N7D-T3 B,N7A-T3 D,N7D-T1 A,N7B-T2 D and N7D-T2 A,and increased the non-photochemical quenching coefficient.For N3A-T7 B,low phosphorus stress increased chlorophyll content and net photosynthetic rate,and there was no significant difference in quantum efficiency in photosystem II.Compared with normal phosphorus,the supply of complex phosphorus significantly reduced the chlorophyll content and photosynthetic physiological parameters of wheat materials except N3A-T7 B,among which N7B-T2 D had the largest decline.There was no significant difference in the chlorophyll fluorescence parameters of N3A-T7 B,and the chlorophyll content increased significantly and the photosynthetic efficiency was enhanced.These results indicate that N3A-T7 B has the potential of compensatory effect in photosynthetic physiology.(4)Low phosphorus stress significantly increased the in vivo and in vitro acid phosphatase activity of wheat materials,of which N3A-T7 B acid phosphatase activity was the highest,and the acid phosphatase activity was significantly reduced after phosphorus resupply compared with low phosphorus stress,N3A-T7 B decreased the most.Low phosphorus stress significantly reduced the activity of cell protective enzyme in wheat genetic material except N3A-T7 B.After phosphorus recovery,the activity of enzyme was significantly increased compared with low phosphorus stress and significantly decreased compared with normal phosphorus treatment.There was no significant difference in the activity of N3A-T7 B cell protective enzyme between different treatments.