Pathogen and characteristics,occurrence law,damage symptom of Paulownia fortunei witches broom disease were simply described,and the control method of the disease was summarized.
The spatial pattern of paulownia witches＇ broom was investigated using an Iwao＇s （m^＊-m） model in Shaanxi Province, China. Iwao＇s （m^＊-m） model revealed that spatial pattern of paulownia witches＇ broom exhib...The spatial pattern of paulownia witches＇ broom was investigated using an Iwao＇s （m^＊-m） model in Shaanxi Province, China. Iwao＇s （m^＊-m） model revealed that spatial pattern of paulownia witches＇ broom exhibited a uniform distribution in sample plots. In this model, characteristics of contagiousness coefficient （a） justified the probability of infection by virus-transmission vectors. For tree age less than six, susceptible individuals were aggregated as clusters in the plots and then mutually repelled over age. A preliminary survey of stand volume show that from age five to six, stand volumes of disease grade II showed excessive vegetative growth and returned to normal level between ages ten and 11. Loss rate of volume increment with disease grade II decreased, and then returned to raising trend both at grades III and IV. This phenomenon is possibly caused by an over-compensation effect and by environmental factors. The redundancy of growth hormones in branches, shoots, leaves, buds and roots increased the stem volume of entire trees.展开更多
This paper dealt with the SDS polyacrymide gel electrophoresis of proteins ahd analysis of the amino acids in the diseasedand healthy leaves with the same strain respectively, which were at the same side and height, o...This paper dealt with the SDS polyacrymide gel electrophoresis of proteins ahd analysis of the amino acids in the diseasedand healthy leaves with the same strain respectively, which were at the same side and height, of Paulownia catalpifolia, P. elongata, P. albiphloea and P. kauakamii respectively. The results indicated that the leaves of 4 species of Paulownia trees with witches' broom had one protein band, of which molecular weight was 12 kD, which did not appear in the healthy leaves free of phytoplasmas. Moreover, the protein quantity in the affected leaves was more than that in the healthy leaves free of phytoplasmas, At the same time, there was significant difference on the amino acids between the healthy and diseased leaves of P. catalpifolia and P. kawakamii. The amount of cystine in the affected leaves was higher than that in the healthy leaves, but the change of amount of phenylalanine in the affected and healthy leaves was contrary.These changes of proteins and amino acids in the leaves might be related to the witches' broom of the Parlounia trees.展开更多
Jujube witches＇ broom is a devastating disease of Ziziphusjujube that occurs in various jujube regions of China. Nucleic acid extracted from midribs of samples collected from three jujube varieties （＂Suanzao＂, ＂L...Jujube witches＇ broom is a devastating disease of Ziziphusjujube that occurs in various jujube regions of China. Nucleic acid extracted from midribs of samples collected from three jujube varieties （＂Suanzao＂, ＂Lajiaozao＂ and ＂Langzao＂） from symptomatic and asymptomatic shoots were tested by random amplified polymorphic DNA analyses. Using 13 different 10 and 11-bp random primers the amplification of jujube DNA was achieved from all the samples; AMI4 primer provided amplification of specific DNA fragments of about 400 bp, only from samples collected from symptomatic plants. No genetic variations in these varieties were identified using the other 11 arbitrary primers; only with primer AL07 it was possible to differentiate ＂Langzao＂ from the other two varieties tested. All the experiments were repeated 2 times and the results were consistent. Compared with PCR analyses with phytoplasma-specific primers, RAPD techniques resulted to be an alternative rapid and sensitive method for detecting jujube phytoplasmas presence in different jujube varieties.展开更多
Somatic embryogenesis receptor-like kinases(SERKs)are receptor-like proteins that contain leucine-rich repeats and are involved in various signaling pathways.This study identified SERK family members in the Paulownia ...Somatic embryogenesis receptor-like kinases(SERKs)are receptor-like proteins that contain leucine-rich repeats and are involved in various signaling pathways.This study identified SERK family members in the Paulownia fortunei genome and analyzed their characteristics and expression profiles using bioinformatics methods.We identified 12 SERK genes with relatively conserved gene structures and motifs that were distributed unevenly on eight Paulownia chromosomes.The gene promoters contained various cis-acting elements that regulated the expression of the PfSERK genes in response to hormones and abiotic stresses.Synteny analysis indicated that 10 segmental duplication events had occurred during evolution of the PfSERK family.The expression profile of PfSERKs in various tissues of Paulownia fortunei was detected by quantitative real-time PCR(qRT-PCR).Many PfSERK genes can respond to drought and salt stress.Combined with RNA-seq and protein interaction network,it is speculated that PfSERK3/11 may participate in the occurrence of Paulownia witches’broom(PaWB)by regulating the plant height of Paulownia.展开更多
Stem segments from diseased Paulownia tomentosaXP, fortunei and leaves from healthy control were transformed with the expression vector p438PRSI via Agrobacterium tumefaciens. The p438PRSI vector contained shiva-1 gen...Stem segments from diseased Paulownia tomentosaXP, fortunei and leaves from healthy control were transformed with the expression vector p438PRSI via Agrobacterium tumefaciens. The p438PRSI vector contained shiva-1 gene, which encodes an antibacterial peptide under the control of a CaMV35S promoter. The regenerated plants from transformed explants were planted in a greenhouse and nursery. PCR and Southern blotting analysis showed that the shiva-1 gene was successfully integrated into the Paulownia genome. Transcription of the integrated shiva-1 gene was confirmed by RT-PCR. Bioassay in the green house and phytoplasma DNA-dot blotting demonstrated that resistance to Paulownia witch＇s broom disease （PWB） increased significantly in shiva-l-transgenic Paulownia. Further investigations indicated that higher Shiva- 1 expression correlated with fewer phytoplasma and less symptoms in diseased transgenic Paulownia. Together, our findings strongly suggest that breeding shiva-1-Paulownia is an effective strategy to control PWB disease.展开更多
The effects of different concentrations of 5-fluorouracil, rifampicin and tetracycline on the phytoplasmas in the Paulownia tomentosa×Paulownia fortunei seedling and the pathogenic protein related to the witches...The effects of different concentrations of 5-fluorouracil, rifampicin and tetracycline on the phytoplasmas in the Paulownia tomentosa×Paulownia fortunei seedling and the pathogenic protein related to the witches’ broom symptom were studied with PCR based on 16S rRNA gene of the phytoplasmas and 2-dimensional electrophoresis of proteins. The results indicated that the plantlets in vitro culture treated with 0.5～300 mg·L -1 5-fluorouracil had little effect on the symptom remission, but those plantlets treated with 100 and 150 mg·L -1 rifampicin for 30 d showed obvious effect on the symptom remission respectively, and the phytoplasmas in the plantlets treated with 150 mg·L -1 rifampicin could not be detected with PCR of 16S rDNA of the phytoplasmas. Moreover, the protein (pI6.8,m 24 ku) which appeared in both the healthy seedling and diseases ones treated with 150 mg·L -1 rifampicin disappeared in the infected seedling and the those without the symptom after treating with rifampicin and tetracycline, and in which existed with phytoplasma through PCR detection.展开更多
Jujube Witches’ Broom (JWB), caused by phytoplasma, is the most serious and destructive disease of Chinese Jujube. The distribution and year_round concentration variation of JWB phytoplasma were studied under fluores...Jujube Witches’ Broom (JWB), caused by phytoplasma, is the most serious and destructive disease of Chinese Jujube. The distribution and year_round concentration variation of JWB phytoplasma were studied under fluorescence microscope using DAPI. The results showed that phytoplasma might exist in the sieve tubes of all organs, phytoplasma contents varied with organs, sides of organs and growing seasons, phytoplasma usually existed in the roots of the same direction with diseased branches. The uneven_distribution could be observed much often in lightly diseased trees than in seriously diseased one. In roots, the content of phytoplasma was highest in May, relatively low in June, July and August, and lowest in December to March. In branches, the content of phytoplasma increased gradually with the rising of the temperature after bud sprouting in April and May, then increased dramatically and reached peak in July and August, thereafter decreased in autumn. From December to February, there was still a large amount of phytoplasma in diseased branches. The content of phytoplasma in branches kept higher than in roots throughout a year.展开更多
The effects of oxytetracycline on the morphology of the seedling with witches’ broom and global DNA methylation level of Paulownia tomentosa × Paulownia fortunei were investigated.The results indicated that the ...The effects of oxytetracycline on the morphology of the seedling with witches’ broom and global DNA methylation level of Paulownia tomentosa × Paulownia fortunei were investigated.The results indicated that the infected seedlings by phytoplasma recovered to normal morphology of the healthy seedlings after being treated with more than 20 mg L-1 oxytetracycline,and the pathogen could not be detected with PCR in the seedlings.The global DNA methylation level of diseased seedlings was lower than that of healthy one.The oxytetracycline treatment was able to increase the DNA methylation level,and the methylation level of the diseased seedlings increased with the dose of applied oxytetracycline.However the increased methylation of infected seedlings with oxytetracycline treatment could still not reach to level of healthy seedling（CK）,even the seedlings treated with lethal oxytetracycline concentration.展开更多
文摘Pathogen and characteristics,occurrence law,damage symptom of Paulownia fortunei witches broom disease were simply described,and the control method of the disease was summarized.
文摘The spatial pattern of paulownia witches＇ broom was investigated using an Iwao＇s （m^＊-m） model in Shaanxi Province, China. Iwao＇s （m^＊-m） model revealed that spatial pattern of paulownia witches＇ broom exhibited a uniform distribution in sample plots. In this model, characteristics of contagiousness coefficient （a） justified the probability of infection by virus-transmission vectors. For tree age less than six, susceptible individuals were aggregated as clusters in the plots and then mutually repelled over age. A preliminary survey of stand volume show that from age five to six, stand volumes of disease grade II showed excessive vegetative growth and returned to normal level between ages ten and 11. Loss rate of volume increment with disease grade II decreased, and then returned to raising trend both at grades III and IV. This phenomenon is possibly caused by an over-compensation effect and by environmental factors. The redundancy of growth hormones in branches, shoots, leaves, buds and roots increased the stem volume of entire trees.
文摘This paper dealt with the SDS polyacrymide gel electrophoresis of proteins ahd analysis of the amino acids in the diseasedand healthy leaves with the same strain respectively, which were at the same side and height, of Paulownia catalpifolia, P. elongata, P. albiphloea and P. kauakamii respectively. The results indicated that the leaves of 4 species of Paulownia trees with witches' broom had one protein band, of which molecular weight was 12 kD, which did not appear in the healthy leaves free of phytoplasmas. Moreover, the protein quantity in the affected leaves was more than that in the healthy leaves free of phytoplasmas, At the same time, there was significant difference on the amino acids between the healthy and diseased leaves of P. catalpifolia and P. kawakamii. The amount of cystine in the affected leaves was higher than that in the healthy leaves, but the change of amount of phenylalanine in the affected and healthy leaves was contrary.These changes of proteins and amino acids in the leaves might be related to the witches' broom of the Parlounia trees.
文摘Jujube witches＇ broom is a devastating disease of Ziziphusjujube that occurs in various jujube regions of China. Nucleic acid extracted from midribs of samples collected from three jujube varieties （＂Suanzao＂, ＂Lajiaozao＂ and ＂Langzao＂） from symptomatic and asymptomatic shoots were tested by random amplified polymorphic DNA analyses. Using 13 different 10 and 11-bp random primers the amplification of jujube DNA was achieved from all the samples; AMI4 primer provided amplification of specific DNA fragments of about 400 bp, only from samples collected from symptomatic plants. No genetic variations in these varieties were identified using the other 11 arbitrary primers; only with primer AL07 it was possible to differentiate ＂Langzao＂ from the other two varieties tested. All the experiments were repeated 2 times and the results were consistent. Compared with PCR analyses with phytoplasma-specific primers, RAPD techniques resulted to be an alternative rapid and sensitive method for detecting jujube phytoplasmas presence in different jujube varieties.
基金the Academic Scientist Fund for Zhongyuan Scholars of Henan Province(Grant No.2018(185))Project of Central Plains Science and Technology Innovation Leading Talents of Henan Province(224200510010).
文摘Somatic embryogenesis receptor-like kinases(SERKs)are receptor-like proteins that contain leucine-rich repeats and are involved in various signaling pathways.This study identified SERK family members in the Paulownia fortunei genome and analyzed their characteristics and expression profiles using bioinformatics methods.We identified 12 SERK genes with relatively conserved gene structures and motifs that were distributed unevenly on eight Paulownia chromosomes.The gene promoters contained various cis-acting elements that regulated the expression of the PfSERK genes in response to hormones and abiotic stresses.Synteny analysis indicated that 10 segmental duplication events had occurred during evolution of the PfSERK family.The expression profile of PfSERKs in various tissues of Paulownia fortunei was detected by quantitative real-time PCR(qRT-PCR).Many PfSERK genes can respond to drought and salt stress.Combined with RNA-seq and protein interaction network,it is speculated that PfSERK3/11 may participate in the occurrence of Paulownia witches’broom(PaWB)by regulating the plant height of Paulownia.
基金the National Natural Science Foundation of China，the President Foundation of the Chinese Academy of Sciences
文摘Stem segments from diseased Paulownia tomentosaXP, fortunei and leaves from healthy control were transformed with the expression vector p438PRSI via Agrobacterium tumefaciens. The p438PRSI vector contained shiva-1 gene, which encodes an antibacterial peptide under the control of a CaMV35S promoter. The regenerated plants from transformed explants were planted in a greenhouse and nursery. PCR and Southern blotting analysis showed that the shiva-1 gene was successfully integrated into the Paulownia genome. Transcription of the integrated shiva-1 gene was confirmed by RT-PCR. Bioassay in the green house and phytoplasma DNA-dot blotting demonstrated that resistance to Paulownia witch＇s broom disease （PWB） increased significantly in shiva-l-transgenic Paulownia. Further investigations indicated that higher Shiva- 1 expression correlated with fewer phytoplasma and less symptoms in diseased transgenic Paulownia. Together, our findings strongly suggest that breeding shiva-1-Paulownia is an effective strategy to control PWB disease.
文摘The effects of different concentrations of 5-fluorouracil, rifampicin and tetracycline on the phytoplasmas in the Paulownia tomentosa×Paulownia fortunei seedling and the pathogenic protein related to the witches’ broom symptom were studied with PCR based on 16S rRNA gene of the phytoplasmas and 2-dimensional electrophoresis of proteins. The results indicated that the plantlets in vitro culture treated with 0.5～300 mg·L -1 5-fluorouracil had little effect on the symptom remission, but those plantlets treated with 100 and 150 mg·L -1 rifampicin for 30 d showed obvious effect on the symptom remission respectively, and the phytoplasmas in the plantlets treated with 150 mg·L -1 rifampicin could not be detected with PCR of 16S rDNA of the phytoplasmas. Moreover, the protein (pI6.8,m 24 ku) which appeared in both the healthy seedling and diseases ones treated with 150 mg·L -1 rifampicin disappeared in the infected seedling and the those without the symptom after treating with rifampicin and tetracycline, and in which existed with phytoplasma through PCR detection.
文摘Jujube Witches’ Broom (JWB), caused by phytoplasma, is the most serious and destructive disease of Chinese Jujube. The distribution and year_round concentration variation of JWB phytoplasma were studied under fluorescence microscope using DAPI. The results showed that phytoplasma might exist in the sieve tubes of all organs, phytoplasma contents varied with organs, sides of organs and growing seasons, phytoplasma usually existed in the roots of the same direction with diseased branches. The uneven_distribution could be observed much often in lightly diseased trees than in seriously diseased one. In roots, the content of phytoplasma was highest in May, relatively low in June, July and August, and lowest in December to March. In branches, the content of phytoplasma increased gradually with the rising of the temperature after bud sprouting in April and May, then increased dramatically and reached peak in July and August, thereafter decreased in autumn. From December to February, there was still a large amount of phytoplasma in diseased branches. The content of phytoplasma in branches kept higher than in roots throughout a year.
文摘The effects of oxytetracycline on the morphology of the seedling with witches’ broom and global DNA methylation level of Paulownia tomentosa × Paulownia fortunei were investigated.The results indicated that the infected seedlings by phytoplasma recovered to normal morphology of the healthy seedlings after being treated with more than 20 mg L-1 oxytetracycline,and the pathogen could not be detected with PCR in the seedlings.The global DNA methylation level of diseased seedlings was lower than that of healthy one.The oxytetracycline treatment was able to increase the DNA methylation level,and the methylation level of the diseased seedlings increased with the dose of applied oxytetracycline.However the increased methylation of infected seedlings with oxytetracycline treatment could still not reach to level of healthy seedling（CK）,even the seedlings treated with lethal oxytetracycline concentration.
