Mapping Cloning And Physiological Characteristics Of Rice Roll-leaf Mutant U56

Yield is closely related to photosynthesis,leaf is the main organ of photosynthesis,leaf morphology such as leaf curl and size can affect photosynthesis.Moderate leaf curl is beneficial to keep the leaves upright and increase the photosynthetic efficiency of the population.In this study,physiological characteristics and functions of rice roll-leaf mutant u56 were analyzed.The main results are as follows:1.Before the tillering stage,the leaf curl of mutant u56 was not obvious,but at the tillering stage,the leaf was extremely curly.Compared with the wild-type Shennong9816,the leaf curl of the mutant increased by 2.94% at seedling stage,41.38% and31.86% at tillering stage and full heading stage,respectively,and the difference was extremely significant.The content of chlorophyll a,chlorophyll b and carotenoid increased 21.34%,54.85% and 18.33%,respectively.The relative water content of the mutant was 0.57% higher than that of the wild type.2.Compared with the wild type Shennong 9816,the blade length of mutant u56 increased by 1.14%,while the length of inverted second leaf and inverted third leaf decreased by 3.10% and 6.73%,respectively.The blade width of mutant u56 significantly increased by 9.36%,6.00% and 5.93%,respectively.The Angle between blade and blade decreased significantly by 16.18%,while the angle between inverted two-leaf and inverted three-leaf increased significantly by 18.46% and 12.71%,respectively.The internode length of inverted first section,inverted third section,inverted fourth section and inverted fifth section decreased by 4.29%,1.96%,10.40%and 33.5% respectively,and the internode length of inverted second section increased by 3.01%.3.Leaf histological analysis showed that there were defects in the development of distal sclerenchyma in the leaves of mutant u56,which may be the direct cause of leaf curl.4.At full panicle stage,compared with the wild type Shennong 9816,the mutant u56 significantly reduced plant height and effective tiller,panicle length and panicle weight,seed setting rate and 1000-grain weight,and the number of solid grains and unfilled grains per panicle increased,resulting in lower yield.5.Compared with the wild type SN9816,the transmittance of mutant u56 at 20 cm,40cm,60 cm and 80 cm away from the canopy increased by 11.06%,67.60%,182.21%and 538.65%,respectively,reaching extremely significant differences(P<0.01),indicating that the mutant u56 has a more compact plant type,higher population light transmittance and higher population light energy utilization rate.6.The BSA method was used to locate the gene on chromosome 9 and further expand the population,the interval was located between 55.3 CM and 65.1 CM,and there were 11 ORFs in the region.The proline that results in translation mutates to serine,a gene mutation that results in a change in the expression of amino acids.