Breeding tomato (Solanum lycopersicum L.) for resistance to biotic and abiotic stresses

Tomato (Solanum lycopersicum L.) is an important vegetable crop cultivated in the tropical and sub-tropical regions of the world. Low productivity in India is due to occurrence of both biotic and abiotic stresses. Among the biotic stresses, tomato leaf curl disease, bacterial wilt, early blight and Groundnut Bud Necrosis Virus disease have become serious production constraints causing considerable yield loss in the major tomato growing areas of the country. Adoption of multiple disease resistant varieties or F1 hybrids would be the most appropriate way to address these diseases. At ICAR-IIHR, Bengaluru systematic breeding strategies were employed to pyramid genes for resistance to early blight, bacterial wilt and tomato leaf curl diseases and to develop advanced breeding lines& F1 hybrids with triple disease resistance. Stable source of resistance to early blight and bi-partite begomo-virus (Tomato Leaf Curl New Delhi Virus) has been identified in Solanum habrochaites LA-1777. Validation with molecular markers linked to tomato leaf curl virus resistance revealed that LA-1777 carryTy2 and other putative resistant genes. Several high yielding dual purpose hybrids were also developed for fresh market and processing with high level of resistance to multiple diseases. Cherry tomato lines have also been bred for high TSS, total carotenoids, total phenols, flavonoids, vitamin C, acidity and lycopene content. IIHR-249-1, IIHR-2101 (Solanum habrochaites LA-1777), IIHR- 2866 and IIHR-2864 recorded high values for quality parameters like total carotenoids, lycopene, vitamin C, total phenols, flavonoids and TSS. Drought tolerant root stock has been developed by an interspecific cross between S. habrochaites LA-1777 and S. lycopersicum (15 SB SB). Resistant sources have also been identified against Tuta absoluta, a serious insect pest reported from major tomato growing areas in the country in recent time. High temperature tolerant breeding lines are in pipe line

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Not AvailableChilli, an important commercial crop, is recalcitrant to in vitro regeneration. In the present study, an attempt has been made to optimize the in vitro regeneration of two chilli local cultivars, viz., G4 and LCA334, and transform G4 with a transcription factor dreb1A under the control of a desiccation inducible promoter rd29A, known to impart desiccation tolerance, using binary vector pCAMBIA 2301. Different phytohormones and their concentrations in MS medium were evaluated for in vitro response; 0.25 mg L-1 zeatin and 2 mg L-1 phenyl acetic acid (PAA) supported the highest regeneration rate (37.86%). Among the explants, cotyledonary leaf exhibited a higher (51%) regeneration response compared to that of hypocotyls (24.73%), and genotype G4 had better (33.80%) regeneration rate compared to LCA334. Rooting of the shoots was the highest in MS medium with 2 mg L-1 indole butyric acid (IBA) compared to other hormones. The presence of transgene was confirmed by polymerase chain reaction (PCR) and Southern blotting. The acclimatized transformants were grown in pots and screened for drought tolerance. Some of the transformants showed improved tolerance to drought by lower wilting compared to the control plants. The transformation and regeneration protocol described in the present study may help in optimization of transformation of chilli for agronomic traits of interest.Not Availabl

<span style="font-size:11.0pt;font-family: "Times New Roman";mso-fareast-font-family:"Times New Roman";mso-bidi-font-family: Mangal;mso-ansi-language:EN-US;mso-fareast-language:EN-US;mso-bidi-language: HI" lang="EN-US">Genetic transformation of chilli (<i style="mso-bidi-font-style:normal">Capsicum annuum</i> L.) with <i style="mso-bidi-font-style:normal">Dreb</i>1A transcription factor known to impart drought tolerance</span>

17-24<span style="font-size:11.0pt;font-family: " times="" new="" roman";mso-fareast-font-family:"times="" roman";mso-bidi-font-family:="" mangal;mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:="" hi"="" lang="EN-US">Chilli, an important commercial crop, is recalcitrant to in vitro regeneration. In the present study, an attempt has been made to optimize the in vitro regeneration of two chilli local cultivars, viz., G4 and LCA334, and transform G4 with a transcription factor dreb1A under the control of a desiccation inducible promoter rd29A, known to impart desiccation tolerance, using binary vector pCAMBIA 2301. Different phytohormones and their concentrations in MS medium were evaluated for in vitro response; 0.25 mg L-1 zeatin and 2 mg L-1 phenyl acetic acid (PAA) supported the highest regeneration rate (37.86%). Among the explants, cotyledonary leaf exhibited a higher (51%) regeneration response compared to that of hypocotyls (24.73%), and genotype G4 had better (33.80%) regeneration rate compared to LCA334. Rooting of the shoots was the highest in MS medium with 2 mg L-1 indole butyric acid (IBA) compared to other hormones. The presence of transgene was confirmed by polymerase chain reaction (PCR) and Southern blotting. The acclimatized transformants were grown in pots and screened for drought tolerance. Some of the transformants showed improved tolerance to drought by  lower wilting compared to the control plants. The transformation and regeneration protocol described in the present study may help in optimization of transformation of chilli for agronomic traits of interest.</span

Not Available

Not AvailableChilli, an important commercial crop, is recalcitrant to in vitro regeneration. In the present study, an attempt has been made to optimize the in vitro regeneration of two chilli local cultivars, viz. , G4 and LCA334, and transform G4 with a transcription factor dreb1A under the control of a desiccation inducible promoter rd29A, known to impart desiccation tolerance, using binary vector pCAMBIA 2301. Different phytohormones and their concentrations in MS medium were evaluated for in vitro response; 0.25 mg L -1 zeatin and 2 mg L -1 phenyl acetic acid (PAA) supported the highest regeneration rate (37.86%). Among the explants, cotyledonary leaf exhibited a higher (51%) regeneration response compared to that of hypocotyls (24.73%), and genotype G4 had better (33.80%) regeneration rate compared to LCA334. Rooting of the shoots was the highest in MS medium with 2 mg L -1 indole butyric acid (IBA) compared to other hormones. The presence of transgene was confirmed by polymerase chain reaction (PCR) and Southern blotting. The acclimatized transformants were grown in pots and screened for drought tolerance. Some of the transformants showed improved tolerance to drought by lower wilting compared to the control plants. The transformation and regeneration protocol described in the present study may help in optimization of transformation of chilli for agronomic traits of interest.Not Availabl

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Not AvailableTomato (Solanum lycopersicum L.) is an important vegetable crop cultivated in the tropical and sub-tropical regions of the world. Low productivity in India is due to occurrence of both biotic and abiotic stresses. Among the biotic stresses, tomato leaf curl disease, bacterial wilt, early blight and Groundnut Bud Necrosis Virus disease have become serious production constraints causing considerable yield loss in the major tomato growing areas of the country. Adoption of multiple disease resistant varieties or F1 hybrids would be the most appropriate way to address these diseases. At ICAR-IIHR, Bengaluru systematic breeding strategies were employed to pyramid genes for resistance to early blight, bacterial wilt and tomato leaf curl diseases and to develop advanced breeding lines& F1 hybrids with triple disease resistance. Stable source of resistance to early blight and bi-partite begomo-virus (Tomato Leaf Curl New Delhi Virus) has been identified in Solanum habrochaites LA-1777. Validation with molecular markers linked to tomato leaf curl virus resistance revealed that LA-1777 carryTy2 and other putative resistant genes. Several high yielding dual purpose hybrids were also developed for fresh market and processing with high level of resistance to multiple diseases. Cherry tomato lines have also been bred for high TSS, total carotenoids, total phenols, flavonoids, vitamin C, acidity and lycopene content. IIHR-249-1, IIHR-2101 (Solanum habrochaites LA-1777), IIHR-2866 and IIHR-2864 recorded high values for quality parameters like total carotenoids, lycopene, vitamin C, total phenols, flavonoids and TSS. Drought tolerant root stock has been developed by an interspecific cross between S. habrochaites LA-1777 and S. lycopersicum (15 SB SB). Resistant sources have also been identified against Tuta absoluta, a serious insect pest reported from major tomato growing areas in the country in recent time. High temperature tolerant breeding lines are in pipe line.Not Availabl

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Not AvailableTomato (Solanum lycopersicum L.) is an important vegetable crop cultivated in the tropical and sub-tropical regions of the world. Low productivity in India is due to occurrence of both biotic and abiotic stresses. Among the biotic stresses, tomato leaf curl disease, bacterial wilt, early blight and Groundnut Bud Necrosis Virus disease have become serious production constraints causing considerable yield loss in the major tomato growing areas of the country. Adoption of multiple disease resistant varieties or F1 hybrids would be the most appropriate way to address these diseases. At ICAR-IIHR, Bengaluru systematic breeding strategies were employed to pyramid genes for resistance to early blight, bacterial wilt and tomato leaf curl diseases and to develop advanced breeding lines& F1 hybrids with triple disease resistance. Stable source of resistance to early blight and bi-partite begomo-virus (Tomato Leaf Curl New Delhi Virus) has been identified in Solanum habrochaites LA-1777. Validation with molecular markers linked to tomato leaf curl virus resistance revealed that LA-1777 carryTy2 and other putative resistant genes. Several high yielding dual purpose hybrids were also developed for fresh market and processing with high level of resistance to multiple diseases. Cherry tomato lines have also been bred for high TSS, total carotenoids, total phenols, flavonoids, vitamin C, acidity and lycopene content. IIHR-249-1, IIHR-2101 (Solanum habrochaites LA-1777), IIHR- 2866 and IIHR-2864 recorded high values for quality parameters like total carotenoids, lycopene, vitamin C, total phenols, flavonoids and TSS. Drought tolerant root stock has been developed by an interspecific cross between S. habrochaites LA-1777 and S. lycopersicum (15 SB SB). Resistant sources have also been identified against Tuta absoluta, a serious insect pest reported from major tomato growing areas in the country in recent time. High temperature tolerant breeding lines are in pipeline.Not Availabl

Variation for natural out-crossing in pigeonpea

Several researchers have reported a considerable degree of natural out-crossing in pigeonpea from different environments. This paper reviews the subject with respect to the variation for natural out-crossability, pollinating vectors, extent of natural out-crossing, isolation specifications, and the possible utilization of natural out-crossing in pigeonpea improvement