Comparisons Of Grafting Compatibility And Growth Fruit Of Orah On The Four Rootstock

Orah is the fastest growing citrus cultivar in Guangxi in recent years.Its main reproductive mode is grafting propagation.At present,there are various types of rootstocks in the production of Citrus sinensis seedlings,and their growth results are different.In order to compare and evaluate t he effects of Different Rootstocks on the grafting compatibility and growt h outcomes of Citrus mandarin,and to provide reference for the breeding of improved varieties and high yield and high quality cultivation of Citr us mandarin,four rootstocks,A(Rifoliate orange Poncirus),B(Sunki man darin),C(Ziyang Xiangcheng)and D(Red tangerine),were used as test materials in this study.The germination rate,enzyme activity and protein changes during the healing process,fruit quality,leaf and fruit quality wer e determined.Soil nutrition,changes of activity of canker leaf enzymes,e tc.were compared among different rootstocks in terms of grafting compati bility,growth and development,and canker resistance,which provided the oretical reference for selecting suitable types of Orah rootstocks in produc tion.The main results are as follows:1.7 and 14 days after grafting,the survival rates of grafted Orah on four rootstocks Poncirus,Sunki mandarin,Ziyang Xiangcheng and Red t angerine were 16.66%,16.66%,13.33%,20%and 32%,28%,40%,56%,r espectively.The germination rate reached 100%after 28 days of grafting.And the ratios of upper and lower diameters of the four rootstocks were 0.82,0.86,0.82 and 0.84,respectively.The soluble protein content,SOD activity,POD activity and PAL activity during grafting healing were not i n accordance with the order of affinity.The relationship between maximu m value and affinity was not obvious.The maximum value of CAT activi ty and PPO activity and affinity were not significant.The order of size is the same,and the relationship with affinity is obvious.2.There was no significant difference in root projection area and dia meter between the four rootstocks.The length of main roots of the four r ootstocks were 24.20cm,28.88cm,25.18cm,23.77cm,respectively.The len gth of main roots of Sunki mandarin rootstocks was significantly longer t han that of the other three rootstocks.3.The plant height of the two-year Orah on the rootstock Trifoliate orange,Orah on the rootstock Sunki mandarin,Orah on the rootstock Ziyan g Xiangcheng and Orah on the rootstock Red tangerine were 159.15cm,148.17cm,134.60cm and 154.90cm,respectively,the crown width were 126.60cm,121.37cm,100.80cm and 114.425cm,respectively.The average sing le fr-uit weight were 164.05g,136.77g,260.22 g and 167.08g,respectively.The average fr-uit shape index were.0.77,0.80,0.86 and 0.78,respectivel y.The average soluble solids contents were 13.37%,12.50%,14.07%and 13.58%,respectively.The average titratable acid content were 0.74g/100 mL,0.58g/100mL,0.79g/100mL and 0.74g/100mL,respectively.The avera ge soluble sugar content were 8.37%,8.00%,9.47%and 8.47%,respectiv ely.The average vitamin Orah on the rootstock Ziyang Xiangcheng conten t were 37.42 mg/100g,34.78 mg/100g,43.07 mg/100g and 39.75 mg/100g,res pectively.The average solid-acid ratios were 18.42,21.57,19.82 and 19.17,respectively.4.Orah leaves of different rootstocks with the same management lev el had yellowing phenomena in varying degrees.The results of leaf yello wing test of four rootstocks of Orah were negative,indicating that leaf ye llowing was not caused by Huanglong disease.There were no physiologic al obstacles such as water damage,freezing injury and fertilizer damage.The results of nutrient analysis of leaves and soil showed that the main c ause of leaf yellowing was the lack or excess of nutrient elements.5.The leaf susceptibility rates of citrus canker of the Orah on the ro otstock Trifoliate orange,Orah on the rootstock Sunki mandarin,Orah on th e rootstock Ziyang Xiangcheng and Orah on the rootstock Red tangerine were 15%,7.5%,50%and 45%,respectively after inoculation with canker fungus;the changes of SOD activity,CAT activity,POD activity and PP O activity of leaf soluble protein content after inoculation with canker fun gus were not consistent with the susceptibility rate,indicating that there was no obvious relationship between PAL activity and canker resistance.The maximum values were 42.53U/(g min),66.67U/(g min),9.33U/(g min)and 15.48U/(g·min),respectively,which were significantly correlated with the resistance to ulcer.6.According to the results of this study,the affinity of four Rootstoc ks to Orah was Orah on the rootstock Red tangerine>Orah on the roots tock Ziyang Xiangcheng>Orah on the rootstock Trifoliate orange>Ora h on the rootstock Sunki mandarin,the highest resistance to canker was Orah on the rootstock Sunki mandarin,the most susceptible was Orah on the rootstock Ziyang Xiangcheng;the best comprehensive performance of fruit quality was Orah on the rootstock Ziyang Xiangcheng,and the wor st was Orah on the rootstock Sunki mandarin.