| Watermelon is an important economical crop in China,but continuous planting in production has led to widespread occurrence of sitting obstacles,especially the occurrence of Fusarium wilt,which has caused serious harm to production.Watermelon Fusarium wilt disease is a kind of soil bacillus disease,which can survive for more than ten years in the soil and incompletely fermented fungal fertilizer,accompanied by the whole growth period of watermelon.There are currently four physiological races of watermelon Fusarium wilt,namely 0,1,2 and 3.In China,physiological race 1 is the dominant race and has the widest range,but physiological race 2 is more invasive and inoculation of physiological race 2 can better reflect its potential disease resistance.Therefore,screening watermelon material with strong resistance to Fusarium wilt is one of the effective ways to control Fusarium wilt,which can provide important high-quality material resources for future breeding of resistant varieties.At the same time,through the analysis and evaluation of the relevant quality of the material,it provides a certain reference for the selection of high-quality watermelon parents and variety breeding.In this study,a total of 19 watermelon materials were selected,of which 10 germplasms,9 varieties and combinations were analyzed and evaluated by the following research methods:1)Inoculation of Fusarium wilt physiological race 2 at seedling stage,and the dynamic incidence of each test material was counted Rate,diseased plant rate,disease index and resistance level;2)combining the growth data of each test material in the continuous stubble field?5 years?to clarify its incidence throughout the growing period and further evaluate its resistance;3)Determine the quality indicators of each test material such as fruit traits,soluble solids,soluble total sugar,lycopene,vitamin C,soluble protein,organic acid and sugar-acid ratio.The main research conclusions are as follows:1. Investigation results of artificial inoculation of Fusarium wilt physiological race 2 at seedling stage showed that the test materials began to develop disease 7 to 9 days after inoculation;11 days after inoculation,the disease occurred most rapidly;after 15 days,the incidence of disease began to increase slowly and stabilize State;on the 17th to 19th days,the incidence rate basically does not change.According to the final incidence of each material,5 copies of intermediate resistance materials?MR,incidence rate 21?50%?were identified:‘M08',‘04-1-2',‘Nong Ke Da No.6',‘M08×P02'And‘Jin Cheng No.5',accounting for 26.3%of the materials tested;12 copies of light resistance materials?LR,incidence rate 51?80%?:‘148',‘XNF',‘Y-118',‘Jin 5F',‘F09',‘97103',‘Yu Nong No.6',‘Qing Long No.3',‘Hong Guanlong',‘Y-118×Jing M',‘Hong Xiaoyu×Y-22'and‘Jing 2×Jin Kang',accounting for 63.2%of the test materials;2 copies of susceptible materials?S,incidence rate 81?100%?:‘Jing M'and‘25 Yuan',accounting for 10.5%of the test materials.2. The investigation results of the incidence of Fusarium wilt on heavy crops showed that there were only materials with high resistance,medium resistance and light resistance,and no susceptible materials.Among them,9 copies of high-resistance materials?HR,incidence rate 0-20%?:‘XNF',‘M08',‘Jin 5F',‘Yu Nong No.6',‘Qing Long No.3',‘Hong Guanlong',‘Nong Ke Da No.6',‘M08×P02'and‘Jin Cheng No.5',accounting for 47.4%of the materials tested;8 copies of medium resistance materials?MR,incidence rate 21?50%?:‘148',‘Y-118',‘04-1-2',‘F09',‘97103',‘Y-118×Jing M',‘Hong Xiaoyu×Y-22'and‘Jing 2×Jin Kang',taking part in the test 42.1%of the materials;2 copies of light-resistant materials?LR,incidence rate 51-80%?:‘Jing M'and‘25 Yuan',accounting for 10.5%of the materials tested.3. The quality index measurement results show that the highest soluble solid content is‘Hong Xiaoyu×Y-22',which is 12.46%,but it is the same as‘Jin Cheng No.5',‘Jing 2×Jin Kang',and‘Nong Ke Da No.6',‘Hong Guanlong',‘Y-118×Jing M',‘M08×P02',‘F09'and‘M08'have no significant difference;the highest soluble total sugar content is‘Hong Xiaoyu×Y-22',It is 41.8 mg·g-1,which is significantly different from other materials;the significantly different from other materials;vitamin C The highest content is‘M08×P02',which is 45.22 mg·kg-1,but it is the same as‘Jincheng 5',‘Hong Xiaoyu×Y-22',‘Y-118×Jing M',‘Hong Guanlong'and‘Y-118';there is no significant difference;the highest soluble protein content is‘Y-118×Jing M',which is 0.69 mg·g-1,but it is the same as‘Jing 2×Jin Kang',‘Hong Xiaoyu×Y-22',‘Qing Long No.3',‘97103'and‘XNF'have no significant difference.The highest organic acid content is‘Nong Ke Da No.6',which is0.77%,but it is the same as‘Qing Long No.3',‘F09'and‘Jing M'has no significant difference;sugar-acid ratio The highest is‘M08×P02',which is 31.10,which is significantly different from other materials.Among germplasms,the single quality of the following germplasms is superior to others:soluble solids of‘Jing M'and‘04-1-2',total soluble sugars of‘Y-118'and‘Jing M',Lycopene of‘F09',‘XNF'and‘04-1-2',vitamin C of‘Y-118',‘F09'and‘25Yuan',Soluble protein of‘F09',‘97103'and‘XNF',Organic acids of‘F09'and‘Jing M',sugar-acid ratio of‘M08'.4. Through the correlation analysis of different resistance and quality indicators,it is found that the resistance of watermelon wilt disease has no direct relationship with quality.According to the diseased plant rate and resistance performance of the test material Fusarium wilt?medium resistance in seedling stage,high resistance in field?,combined with soluble solids,soluble total sugar and sugar-acid ratio as the main quality indicators,refer to other quality indicators,6 materials with strong resistance to wilt and good quality were selected:1)‘M08'(middle resistance at seedling stage,diseased plant rate 32.81%,high resistance to repeated cropping,diseased plant rate 3.27%,soluble solids content 11.05%,total soluble Sugar 26.88 g·kg-1);2)‘04-1-2'(intermediate resistance,diseased plant rate at seedling stage 40.48%,intermediate resistance and diseased plant rate at repeated cropping field 33.37%,soluble solids content 10.22%,total soluble sugar 24.68 g·kg-1);3)‘M08×P02'?medium resistance,diseased plant rate 21.63%at seedling stage,high resistance,diseased plant rate 10.07%in stubble field,soluble solid content 11.16%,sugar-acid ratio31.10?;4)‘'Nongkeda No.6'(middle resistance,diseased plant rate 23.19%at seedling stage,high resistance,diseased plant rate 16.73%in stubble field,soluble solid content11.75%,total soluble sugar 32.84 g·kg-1);5)‘Jincheng No.5'(intermediate resistance,diseased plant rate 27.11%at seedling stage,high resistance,diseased plant rate 16.73%in repeated cropping field,soluble solid The content of the material is 12.11%,the total soluble sugar is 31.92 g·kg-1);6)‘Hong Guanlong'(light resistance at seedling stage,diseased plant rate 57.50%,high resistance to repeated cropping,diseased plant rate 13.27%,soluble solid content 11.63%,total soluble sugar 26.91 g·kg-1). |
PDF Full Text Request