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Srinivasa Rao Uppalapati - One of the best experts on this subject based on the ideXlab platform.
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ntrc and chloroplast generated reactive oxygen species regulate pseudomonas syringae pv tomato disease development in tomato and arabidopsis
Molecular Plant-microbe Interactions, 2012Co-Authors: Yasuhiro Ishiga, Takako Ishiga, Kirankumar S. Mysore, Tamding Wangdi, Srinivasa Rao UppalapatiAbstract:Coronatine (COR)-producing pathovars of Pseudomonas syringae, including pvs. tomato, maculicola, and glycinea, cause important diseases on tomato, crucifers, and soybean, respectively, and produce symptoms with necrotic lesions surrounded by Chlorosis. The Chlorosis is mainly attributed to COR. However, the significance of COR-induced Chlorosis in localized lesion development and the molecular basis of disease-associated cell death is largely unknown. To identify host (chloroplast) genes that play a role in CORmediated Chlorosis, we used a forward genetics approach using Nicotiana benthamiana and virus-induced gene silencing and identified a gene which encodes 2-Cys peroxiredoxin (Prxs) that, when silenced, produced a spreading hypersensitive or necrosis-like phenotype instead of Chlorosis after COR application in a COI1-dependent manner. Loss-of-function analysis of Prx and NADPH-dependent thioredoxin reductase C (NTRC), the central players of a chloroplast redox detoxification system, resulted in spreading accelerated P. syringae pv. tomato DC3000 disease-associated cell death with enhanced reactive oxygen species (ROS) accumulation in a COR-dependent manner in tomato and Arabidopsis. Consistent with these results, virulent strain DC3000 suppressed the expression of Prx and NTRC in Arabidopsis and tomato during pathogenesis. However, interestingly, authentic COR suppressed the expression of Prx and NTRC in tomato but not in Arabidopsis, suggesting that COR in conjunction with other effectors may modulate ROS and cell death in different host species. Taken together, these results indicated that NTRC or Prx function as a negative regulator of pathogen-induced cell death in the healthy tissues that surround the lesions, and CORinduced chloroplast-localized ROS play a role in enhancing the disease-associated cell death.
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SGT1 contributes to coronatine signaling and Pseudomonas syringae pv. tomato disease symptom development in tomato and Arabidopsis
New Phytologist, 2011Co-Authors: Srinivasa Rao Uppalapati, Yasuhiro Ishiga, Choong-min Ryu, Takako Ishiga, Keri Wang, Laurent Noel, Jane Parker, Kirankumar S. MysoreAbstract:Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) causes an economically important bacterial speck disease on tomato and produces symptoms with necrotic lesions surrounded by Chlorosis. The Chlorosis is mainly attributed to a jasmonic acid (JA)-isoleucine analogue, coronatine (COR), produced by Pst DC3000. However, the molecular processes underlying lesion development and COR-induced Chlorosis are poorly understood. In this study, we took advantage of a chlorotic phenotype elicited by COR on Nicotiana benthamiana leaves and virus-induced gene silencing (VIGS) as a rapid reverse genetic screening tool and identified a role for SGT1 suppressor of G2 allele of skp1) in COR-induced Chlorosis. Silencing of SGT1 in tomato resulted in reduction of disease-associated symptoms (cell death and Chlorosis), suggesting a molecular connection between CORinduced Chlorosis and cell death. In Arabidopsis, AtSGT1b but not AtSGT1a was required for COR responses, including root growth inhibition and Pst DC3000 symptom (water soaked lesion) development. Notably, overexpression of AtSGT1b did not alter Pst DC3000 symptoms or sensitivity to COR. Taken together, our results demonstrate that SGT1 ⁄ SGT1b is required for CORinduced Chlorosis and subsequent necrotic disease development in tomato and Arabidopsis. SGT1 is therefore a component of the COR⁄ JA-mediated signal transduction pathway.
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involvement of coronatine inducible reactive oxygen species in bacterial speck disease of tomato
Plant Signaling & Behavior, 2009Co-Authors: Yasuhiro Ishiga, Srinivasa Rao Uppalapati, Takako Ishiga, Sathya Elavarthi, B C Martin, Carol L BenderAbstract:Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) produces a Chlorosis-inducing phytotoxin coronatine (COR), which has multiple virulence functions in planta. One of the hallmarks of bacterial speck disease on tomato leaves is the formation of necrotic lesions surrounded by Chlorosis. The physiological significance of COR-induced Chlorosis in disease development is still unknown. In our recent publication in New Phytologist, we demonstrated that COR-induced effects on photosynthetic machinery resulted in the accumulation of reactive oxygen species (ROS). Tomato seedlings inoculated with Pst DC3000 and incubated in light showed more disease-associated necrotic cell death than inoculated seedlings COR suppressed the expression of thylakoid-localized Cu/Zn superoxide dismutase (Cu/Zn SOD), but not the cytosolic-localized Cu/Zn SOD. In this addendum, we propose a model for the function of COR as a regulator of plant ROS production in different cellular sites leading to disease-associated necrotic cell death during bacterial speck of tomato.
Yasuhiro Ishiga - One of the best experts on this subject based on the ideXlab platform.
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ntrc and chloroplast generated reactive oxygen species regulate pseudomonas syringae pv tomato disease development in tomato and arabidopsis
Molecular Plant-microbe Interactions, 2012Co-Authors: Yasuhiro Ishiga, Takako Ishiga, Kirankumar S. Mysore, Tamding Wangdi, Srinivasa Rao UppalapatiAbstract:Coronatine (COR)-producing pathovars of Pseudomonas syringae, including pvs. tomato, maculicola, and glycinea, cause important diseases on tomato, crucifers, and soybean, respectively, and produce symptoms with necrotic lesions surrounded by Chlorosis. The Chlorosis is mainly attributed to COR. However, the significance of COR-induced Chlorosis in localized lesion development and the molecular basis of disease-associated cell death is largely unknown. To identify host (chloroplast) genes that play a role in CORmediated Chlorosis, we used a forward genetics approach using Nicotiana benthamiana and virus-induced gene silencing and identified a gene which encodes 2-Cys peroxiredoxin (Prxs) that, when silenced, produced a spreading hypersensitive or necrosis-like phenotype instead of Chlorosis after COR application in a COI1-dependent manner. Loss-of-function analysis of Prx and NADPH-dependent thioredoxin reductase C (NTRC), the central players of a chloroplast redox detoxification system, resulted in spreading accelerated P. syringae pv. tomato DC3000 disease-associated cell death with enhanced reactive oxygen species (ROS) accumulation in a COR-dependent manner in tomato and Arabidopsis. Consistent with these results, virulent strain DC3000 suppressed the expression of Prx and NTRC in Arabidopsis and tomato during pathogenesis. However, interestingly, authentic COR suppressed the expression of Prx and NTRC in tomato but not in Arabidopsis, suggesting that COR in conjunction with other effectors may modulate ROS and cell death in different host species. Taken together, these results indicated that NTRC or Prx function as a negative regulator of pathogen-induced cell death in the healthy tissues that surround the lesions, and CORinduced chloroplast-localized ROS play a role in enhancing the disease-associated cell death.
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SGT1 contributes to coronatine signaling and Pseudomonas syringae pv. tomato disease symptom development in tomato and Arabidopsis
New Phytologist, 2011Co-Authors: Srinivasa Rao Uppalapati, Yasuhiro Ishiga, Choong-min Ryu, Takako Ishiga, Keri Wang, Laurent Noel, Jane Parker, Kirankumar S. MysoreAbstract:Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) causes an economically important bacterial speck disease on tomato and produces symptoms with necrotic lesions surrounded by Chlorosis. The Chlorosis is mainly attributed to a jasmonic acid (JA)-isoleucine analogue, coronatine (COR), produced by Pst DC3000. However, the molecular processes underlying lesion development and COR-induced Chlorosis are poorly understood. In this study, we took advantage of a chlorotic phenotype elicited by COR on Nicotiana benthamiana leaves and virus-induced gene silencing (VIGS) as a rapid reverse genetic screening tool and identified a role for SGT1 suppressor of G2 allele of skp1) in COR-induced Chlorosis. Silencing of SGT1 in tomato resulted in reduction of disease-associated symptoms (cell death and Chlorosis), suggesting a molecular connection between CORinduced Chlorosis and cell death. In Arabidopsis, AtSGT1b but not AtSGT1a was required for COR responses, including root growth inhibition and Pst DC3000 symptom (water soaked lesion) development. Notably, overexpression of AtSGT1b did not alter Pst DC3000 symptoms or sensitivity to COR. Taken together, our results demonstrate that SGT1 ⁄ SGT1b is required for CORinduced Chlorosis and subsequent necrotic disease development in tomato and Arabidopsis. SGT1 is therefore a component of the COR⁄ JA-mediated signal transduction pathway.
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involvement of coronatine inducible reactive oxygen species in bacterial speck disease of tomato
Plant Signaling & Behavior, 2009Co-Authors: Yasuhiro Ishiga, Srinivasa Rao Uppalapati, Takako Ishiga, Sathya Elavarthi, B C Martin, Carol L BenderAbstract:Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) produces a Chlorosis-inducing phytotoxin coronatine (COR), which has multiple virulence functions in planta. One of the hallmarks of bacterial speck disease on tomato leaves is the formation of necrotic lesions surrounded by Chlorosis. The physiological significance of COR-induced Chlorosis in disease development is still unknown. In our recent publication in New Phytologist, we demonstrated that COR-induced effects on photosynthetic machinery resulted in the accumulation of reactive oxygen species (ROS). Tomato seedlings inoculated with Pst DC3000 and incubated in light showed more disease-associated necrotic cell death than inoculated seedlings COR suppressed the expression of thylakoid-localized Cu/Zn superoxide dismutase (Cu/Zn SOD), but not the cytosolic-localized Cu/Zn SOD. In this addendum, we propose a model for the function of COR as a regulator of plant ROS production in different cellular sites leading to disease-associated necrotic cell death during bacterial speck of tomato.
Anunciacion Abadia - One of the best experts on this subject based on the ideXlab platform.
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effects of moderate and severe iron deficiency Chlorosis on fruit yield appearance and composition in pear pyrus communis l and peach prunus persica l batsch
Environmental and Experimental Botany, 2011Co-Authors: Ana Alvarezfernandez, Juan Carlos Melgar, Javier Abadia, Anunciacion AbadiaAbstract:The effects of different levels of Fe-deficiency Chlorosis on the fruit yield, appearance and composition of pear and peach trees grown in field orchards have been studied. The major effect of Fe deficiency in both species was a large yield reduction, even when Chlorosis was moderate, associated to decreases in fruit tree load. Fruit size increased with moderate Chlorosis in both species and decreased with severe Chlorosis in peach. In peach, moderate or severe Chlorosis affected uniformly all branches, leading to firmer fruits with higher acidity, total phenolics and carboxylates. This indicates a delayed maturity that can be attributed to a low C-availability for fruits. In Fe-deficient pear trees, the majority of fruits (98%) were on non-chlorotic or moderately chlorotic branches, and fruits were less green and firm with an increased sugars/acids ratio. This indicates an advanced fruit maturity that can be attributed to an increased C-availability for fruits. All Chlorosis levels increased within-tree variation in fruit appearance.
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foliar fertilization to control iron Chlorosis in pear pyrus communis l trees
Plant and Soil, 2004Co-Authors: Ana Alvarezfernandez, Javier Abadia, P Garcialavina, C Fidalgo, Anunciacion AbadiaAbstract:The effectiveness of foliar fertilization to re-green chlorotic leaves in iron-deficient pear trees has been studied. Trials were made to assess the influence of (i) the level of Fe deficiency, (ii) the leaf surface treated (adaxial or abaxial), and (iii) two different surfactants, L-77 and Mistol. Treatments were ferrous sulphate alone, ascorbic, citric and sulphuric acids, applied either alone or in combination with ferrous sulphate, Fe-DTPA and water as a control. Solutions were applied with a brush and leaves were treated twice each year. None of the treatments caused a full recovery from Fe deficiency Chlorosis. Treatments containing Fe caused the largest re-greening effects, and FeSO4 had a similar re-greening effect to Fe(III)-DTPA. Increases in leaf Chl were more pronounced with abaxial leaf surface applications and in severely deficient leaves. Using Fe(III)-DTPA in foliar sprays does not seem to be justified, since their effects are not better than those of FeSO4. The joint use of Fe(III)-DTPA and L-77 and that of FeSO4 and citric acid do not seem to be suitable. With a single foliar application, FeSO4 combined with acids gave slightly better results than FeSO4 alone. Acidic solution applications without Fe may be effective in alleviating Chlorosis in some cases, especially in the case of citric acid. In the current state of knowledge, foliar fertilization cannot offer yet a good alternative for full control of Fe Chlorosis, although its low environmental impact and cost make this technique a good complementary measure to soil Fe-chelate applications and other Chlorosis alleviation management techniques.
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agronomic means for the control of iron deficiency Chlorosis in deciduous fruit trees
Journal of Plant Nutrition, 2000Co-Authors: Massimo Tagliavini, Adamo Domenico Rombola, Javier Abadia, Anunciacion Abadia, C Tsipouridis, Bruno MarangoniAbstract:Abstract Iron deficiency induced Chlorosis represents the main nutritional disorder in fruit tree orchards grown on calcareous and/or alkaline soils. Until rootstocks tolerant to Fe deficiency Chlorosis are available for most susceptible fruit species, the agronomic means of preventing or curing Fe deficiency Chlorosis will be considered of utmost importance by fruit growers. Chlorosis of fruit trees has been successfully controlled through foliar or soil applications of Fe chelates, which are expensive and have to be applied annually. In this paper results of research carried out within an EU joint research project are reported, where the effectiveness of alternative, low‐input, environmentally friendly management techniques to control Fe deficiency Chlorosis has been tested in established kiwifruit, peach and pear orchards located in the Po Valley (Italy), in the Ebro Valley (Spain) and in the area of Imathia (Greece). Iron sulphate supply to the soil proved to be effective only if applied together with...
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iron Chlorosis paradox in fruit trees
Journal of Plant Nutrition, 1998Co-Authors: Fermin Morales, Anunciacion Abadia, Roberto Grasa, Javier AbadiaAbstract:Abstract We have investigated the effect of iron (Fe) Chlorosis on leaf Fe, leaf chlorophyll, leaf area, leaf thickness, leaf fresh and dry weight and specific leaf weight per area in young, fully developed leaves of Fe‐deficient and Fe‐sufficient peach (Prunus persica L. Batsch) and pear (Pyrus communis L.) trees growing in the field in northeastern Spain. Iron Chlorosis decreased leaf chlorophyll concentration, fresh and dry weight per leaf and leaf area, whereas leaf thickness was practically unaffected. Chlorosis caused differences in leaf Fe concentrations that were best detected on a per leaf basis. Significant differences in Fe concentration could be detectable in pear on an area basis or a volume basis. However, when expressed on a per dry weight basis the Fe concentrations of control and chlorotic leaves were not significantly different. The fact that chlorotic leaves have less Fe per leaf confirms that the chlorotic trees are under a short supply of Fe. However, chlorotic fruit tree leaves have ...
Takako Ishiga - One of the best experts on this subject based on the ideXlab platform.
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ntrc and chloroplast generated reactive oxygen species regulate pseudomonas syringae pv tomato disease development in tomato and arabidopsis
Molecular Plant-microbe Interactions, 2012Co-Authors: Yasuhiro Ishiga, Takako Ishiga, Kirankumar S. Mysore, Tamding Wangdi, Srinivasa Rao UppalapatiAbstract:Coronatine (COR)-producing pathovars of Pseudomonas syringae, including pvs. tomato, maculicola, and glycinea, cause important diseases on tomato, crucifers, and soybean, respectively, and produce symptoms with necrotic lesions surrounded by Chlorosis. The Chlorosis is mainly attributed to COR. However, the significance of COR-induced Chlorosis in localized lesion development and the molecular basis of disease-associated cell death is largely unknown. To identify host (chloroplast) genes that play a role in CORmediated Chlorosis, we used a forward genetics approach using Nicotiana benthamiana and virus-induced gene silencing and identified a gene which encodes 2-Cys peroxiredoxin (Prxs) that, when silenced, produced a spreading hypersensitive or necrosis-like phenotype instead of Chlorosis after COR application in a COI1-dependent manner. Loss-of-function analysis of Prx and NADPH-dependent thioredoxin reductase C (NTRC), the central players of a chloroplast redox detoxification system, resulted in spreading accelerated P. syringae pv. tomato DC3000 disease-associated cell death with enhanced reactive oxygen species (ROS) accumulation in a COR-dependent manner in tomato and Arabidopsis. Consistent with these results, virulent strain DC3000 suppressed the expression of Prx and NTRC in Arabidopsis and tomato during pathogenesis. However, interestingly, authentic COR suppressed the expression of Prx and NTRC in tomato but not in Arabidopsis, suggesting that COR in conjunction with other effectors may modulate ROS and cell death in different host species. Taken together, these results indicated that NTRC or Prx function as a negative regulator of pathogen-induced cell death in the healthy tissues that surround the lesions, and CORinduced chloroplast-localized ROS play a role in enhancing the disease-associated cell death.
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SGT1 contributes to coronatine signaling and Pseudomonas syringae pv. tomato disease symptom development in tomato and Arabidopsis
New Phytologist, 2011Co-Authors: Srinivasa Rao Uppalapati, Yasuhiro Ishiga, Choong-min Ryu, Takako Ishiga, Keri Wang, Laurent Noel, Jane Parker, Kirankumar S. MysoreAbstract:Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) causes an economically important bacterial speck disease on tomato and produces symptoms with necrotic lesions surrounded by Chlorosis. The Chlorosis is mainly attributed to a jasmonic acid (JA)-isoleucine analogue, coronatine (COR), produced by Pst DC3000. However, the molecular processes underlying lesion development and COR-induced Chlorosis are poorly understood. In this study, we took advantage of a chlorotic phenotype elicited by COR on Nicotiana benthamiana leaves and virus-induced gene silencing (VIGS) as a rapid reverse genetic screening tool and identified a role for SGT1 suppressor of G2 allele of skp1) in COR-induced Chlorosis. Silencing of SGT1 in tomato resulted in reduction of disease-associated symptoms (cell death and Chlorosis), suggesting a molecular connection between CORinduced Chlorosis and cell death. In Arabidopsis, AtSGT1b but not AtSGT1a was required for COR responses, including root growth inhibition and Pst DC3000 symptom (water soaked lesion) development. Notably, overexpression of AtSGT1b did not alter Pst DC3000 symptoms or sensitivity to COR. Taken together, our results demonstrate that SGT1 ⁄ SGT1b is required for CORinduced Chlorosis and subsequent necrotic disease development in tomato and Arabidopsis. SGT1 is therefore a component of the COR⁄ JA-mediated signal transduction pathway.
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involvement of coronatine inducible reactive oxygen species in bacterial speck disease of tomato
Plant Signaling & Behavior, 2009Co-Authors: Yasuhiro Ishiga, Srinivasa Rao Uppalapati, Takako Ishiga, Sathya Elavarthi, B C Martin, Carol L BenderAbstract:Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) produces a Chlorosis-inducing phytotoxin coronatine (COR), which has multiple virulence functions in planta. One of the hallmarks of bacterial speck disease on tomato leaves is the formation of necrotic lesions surrounded by Chlorosis. The physiological significance of COR-induced Chlorosis in disease development is still unknown. In our recent publication in New Phytologist, we demonstrated that COR-induced effects on photosynthetic machinery resulted in the accumulation of reactive oxygen species (ROS). Tomato seedlings inoculated with Pst DC3000 and incubated in light showed more disease-associated necrotic cell death than inoculated seedlings COR suppressed the expression of thylakoid-localized Cu/Zn superoxide dismutase (Cu/Zn SOD), but not the cytosolic-localized Cu/Zn SOD. In this addendum, we propose a model for the function of COR as a regulator of plant ROS production in different cellular sites leading to disease-associated necrotic cell death during bacterial speck of tomato.
Kirankumar S. Mysore - One of the best experts on this subject based on the ideXlab platform.
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ntrc and chloroplast generated reactive oxygen species regulate pseudomonas syringae pv tomato disease development in tomato and arabidopsis
Molecular Plant-microbe Interactions, 2012Co-Authors: Yasuhiro Ishiga, Takako Ishiga, Kirankumar S. Mysore, Tamding Wangdi, Srinivasa Rao UppalapatiAbstract:Coronatine (COR)-producing pathovars of Pseudomonas syringae, including pvs. tomato, maculicola, and glycinea, cause important diseases on tomato, crucifers, and soybean, respectively, and produce symptoms with necrotic lesions surrounded by Chlorosis. The Chlorosis is mainly attributed to COR. However, the significance of COR-induced Chlorosis in localized lesion development and the molecular basis of disease-associated cell death is largely unknown. To identify host (chloroplast) genes that play a role in CORmediated Chlorosis, we used a forward genetics approach using Nicotiana benthamiana and virus-induced gene silencing and identified a gene which encodes 2-Cys peroxiredoxin (Prxs) that, when silenced, produced a spreading hypersensitive or necrosis-like phenotype instead of Chlorosis after COR application in a COI1-dependent manner. Loss-of-function analysis of Prx and NADPH-dependent thioredoxin reductase C (NTRC), the central players of a chloroplast redox detoxification system, resulted in spreading accelerated P. syringae pv. tomato DC3000 disease-associated cell death with enhanced reactive oxygen species (ROS) accumulation in a COR-dependent manner in tomato and Arabidopsis. Consistent with these results, virulent strain DC3000 suppressed the expression of Prx and NTRC in Arabidopsis and tomato during pathogenesis. However, interestingly, authentic COR suppressed the expression of Prx and NTRC in tomato but not in Arabidopsis, suggesting that COR in conjunction with other effectors may modulate ROS and cell death in different host species. Taken together, these results indicated that NTRC or Prx function as a negative regulator of pathogen-induced cell death in the healthy tissues that surround the lesions, and CORinduced chloroplast-localized ROS play a role in enhancing the disease-associated cell death.
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SGT1 contributes to coronatine signaling and Pseudomonas syringae pv. tomato disease symptom development in tomato and Arabidopsis
New Phytologist, 2011Co-Authors: Srinivasa Rao Uppalapati, Yasuhiro Ishiga, Choong-min Ryu, Takako Ishiga, Keri Wang, Laurent Noel, Jane Parker, Kirankumar S. MysoreAbstract:Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) causes an economically important bacterial speck disease on tomato and produces symptoms with necrotic lesions surrounded by Chlorosis. The Chlorosis is mainly attributed to a jasmonic acid (JA)-isoleucine analogue, coronatine (COR), produced by Pst DC3000. However, the molecular processes underlying lesion development and COR-induced Chlorosis are poorly understood. In this study, we took advantage of a chlorotic phenotype elicited by COR on Nicotiana benthamiana leaves and virus-induced gene silencing (VIGS) as a rapid reverse genetic screening tool and identified a role for SGT1 suppressor of G2 allele of skp1) in COR-induced Chlorosis. Silencing of SGT1 in tomato resulted in reduction of disease-associated symptoms (cell death and Chlorosis), suggesting a molecular connection between CORinduced Chlorosis and cell death. In Arabidopsis, AtSGT1b but not AtSGT1a was required for COR responses, including root growth inhibition and Pst DC3000 symptom (water soaked lesion) development. Notably, overexpression of AtSGT1b did not alter Pst DC3000 symptoms or sensitivity to COR. Taken together, our results demonstrate that SGT1 ⁄ SGT1b is required for CORinduced Chlorosis and subsequent necrotic disease development in tomato and Arabidopsis. SGT1 is therefore a component of the COR⁄ JA-mediated signal transduction pathway.