[目的]番茄红素合成后会在β-番茄红素环化酶SlLCY-B(lycopene-β-cyclase)催化下进入代谢途径,抑制SlLCY-B2 的表达可增加番茄红素的积累.对番茄红素代谢调控基因SlLCY-B1 的分子特征及sgRNA进行系统分析,为利用CRISPR/Cas9 技术对SlLCY-B2 及其上游启动子序列进行定点突变或片段删除、调控SlLCY-B2 的表达以减少代谢的途径,提高番茄果实的番茄红素含量.[方法]利用生物在线工具,对SlLCY-B2 多肽特性及保守结构域、基因组结构、数字表达谱、启动子顺式作用元件进行系统分析,根据CRISPR-Cas9 靶点设计原则,设计筛选出适宜的sgRNA.[结果]SlLCY-B2 位于番茄 6 号染色体,编码 498个氨基酸,gDNA不含内含子,呈果实特异性表达.SlLCY-B2 分布 145 条 sgRNA,其中 21 条有高特异性.SlLCY-B2 上游-1 500 bp 启动子序列分布15 个顺式作用元件和112 条sgRNA.[结论]对SlLCY-B2 和其启动子区进行基因编辑,可调控SlLCY-B2 的表达,将提高番茄红素含量.
[Objective]In order to determine the suitable planting density of JI JC4 and JI JC7 in Hebei cotton area,the effects of different planting densities on growth and development,yield,quality and disease resistance were studied.[Methods]4 different planting densities(4.5 × 104,9 ×104,13.5 ×104 and 18 × 104 plant/hm2)were set to investigate the agronomic traits,yield,quality and disease resistance of cotton,and the optimum planting densities of JI JC4 and JI JC7 were comprehensively analyzed.[Results]With the increase of planting density,the plant height of JI JC4 and JI JC7 decreased,the height of the first node of fruit branch increased,and the whole growth period delayed.The lint yield of JI JC4 was higher with the in-crease of planting density,and the difference was obvious.The density of JI JC7 line had little effect on lint yield.Different planting densities had effect on micronaire value of JI JC4,on elongation of JI JC7,and had no significant effect on other cotton fiber quality indexes.With the increase of planting density,Verticillium wilt disease index decreased and its resistance increased.[Conclusion]Overall,the suitable planting density of JI JC4 and JI JC7 were 13.5 × 104 plant/hm2.
[Objective]Reproductive output and germination characteristicsof Salsola rosacea in the hope of providing relevant data support for future research on seed heteromorphism and providing theoretical basis for the study on the ecological adaptation mechanism and evolution of seed heteromorphism in desert conditions.[Methods]To study the seed polymorphism,Seeds were classified according to their shape,size,color and growth mode,and germination characteristics of different types of seeds were investigated.The plants are gra-ded according to the dry weight of the plant,and then the reproduction distribution and seed output of plant are calculated.[Results]Three types of seeds were produced in S.rosacea.Type A was green and winged with high germination rate,and type B and C were yellow short-winged/wingless and could be dormant.The pro-portion of reproductive allocation of type A and B increased with increasing of plant class,which showed de-pendence on plant size,while type C showed no dependence.The output proportion of type A decreased with increasing of plant rank,while that of type B seeds increased with the increase of equal size which was de-pendent on the size of plant.No significant change was found in the output of type C seeds.[Conclusion]Three kinds of seeds with different dispersal patterns and germination behaviors can be produced in S.rosacea,and their reproduction allocation and seed output depend on plant size.
[Objective]To study the drought resistance at seed germination stage of six Liaomian cotton varieties under PEG simulated drought stress.[Methods]The seeds of six Liaomian varieties were used as the testing materials to study drought resistance at seed germination stage under different concentrations of PEG-6000(0,2.5％,5.0％,7.5％and 10.0％).Germination energy,germination rate,germination index,germination drought resistance index,hypocotyl length,root length,seedling fresh weight and root fresh weight were measured under different drought stress.[Results]The germination of cotton seeds was inhibited to dif-ferent degrees,and the germination energy,germination rate and germination drought resistance index were decreased with the increase of PEG concentrations.Seedling growth index and root growth index were signifi-cantly inhibited under 2.5％PEG stress.5.0％PEG stress promoted root length growth of all materials.The inhibition degrees of each index under PEG stress above 5.0％concentration were gradually increased with the increase of stress.[Conclusion]The six Liaomian cotton varieties were sorted according to their drought resist-ance as follows:Liaomian 10＞Liaomian 23＞Liaomian 45＞Liaomian 53＞Liaomian 49＞Liaomian 34.
[Objective]Its line for fresh and raisins,this project aims to select high yield and good quali-ty in the hope of providing the foundation for the grape's cultivation with high quality and high yield.[Meth-ods]18 diverse lines of this variety were taken as materials,Thompson seedless grape was used as control,the characters of bunch were described,the fruit quality was determined and drying test was carried out.[Re-sults]Bunch weight of long-bunch Thompson seedless and Ningxia Thompson seedless were 620.20 and 632.67 g respectively,which were 2.25 times and 2.29 times compared with CK.Berry weight of W3 was maximum and 3.10 g,followed by big-berry Thompson seedless and berry weight was 2.45 g,which was 2.35 times and 2.97 times respectively.The soluble solid content of 18 lines was lower than that of CK,the reducing sugar contents of big-berry Thompson seedless,W5 and W9 were 1.34％,1.91％and 3.17％higher than that of CK respectively,the sugar-acid ratio of W5,Zaowuhebai and Hongxiu were significantly higher than that of CK,and increased by 18.11％,23.34％and 22.97％,VC of big-berry Thompson seed-less and W3 were significantly higher than that of CK,and increased by 6.65％and 3.98.In terms of drying characteristics,dry rate of big-berry Thompson seedless and W8 were 6.65％and 3.98％higher than that of CK.In addition,shape index of long-berry Thompson seedless raisins was 3.10 and 1.46 times compared with CK,and popular in the market.Zaowuhebai was pink and raisins had unique appearance with yellow-red-reddish-brown color.[Conclusion]Long-bunch Thompson seedless,big-berry Thompson seedless and long-berry Thompson seedless have excellent performance,which,in addition,Zaowuhebai can be used as a characteristic strain.
