The lengths of mesocotyl in the seedlings of 84 lowland rice varieties and 12 upland rice varieties were measured following the treatments of daylight and darkness during germination. The elongation of mesocotyl in th...The lengths of mesocotyl in the seedlings of 84 lowland rice varieties and 12 upland rice varieties were measured following the treatments of daylight and darkness during germination. The elongation of mesocotyl in the varieties tested was inhibited under daylight condition, and the mesocotyl of all the varieties elongated variably under darkness condition. The elongated lengths of the mesocotyl in upland rice, ranging from 0.36 cm to 1,61 cm with an average of 0.81 cm, was obviously longer than those in lowland rice, ranging from 0.12 cm to 1.56 cm with an average of 0.42 cm. Among 14 rice varieties with over 1 cm of mesocotyl length, five belonged to upland rice, and nine to lowland rice. The possible utilization of the elongated-mesocotyl rice germplasm in varietal imorovement, direct-seeded plantina and seed ouritv testina were discussed.展开更多
In order to evaluate,screen and identify waterlogging-tolerant Brassica napus resources and provide good germplasm materials for breeding of waterlogging-tolerant rape,608 B. napus germplasm materials from different s...In order to evaluate,screen and identify waterlogging-tolerant Brassica napus resources and provide good germplasm materials for breeding of waterlogging-tolerant rape,608 B. napus germplasm materials from different sources were identified and screened for waterlogging-tolerant germplasms. The identification results showed that tested materials had dead seedling rates in the range of 0-100%,indicating that these rape germplasm materials varied extensively in waterlogging tolerance. Among the 608 materials,waterlogging-tolerant materials( grade I,relative dead seedling rate≤21%) accounted for 25. 49%; non-tolerant materials( grade Ⅳ + V,dead seedling rate≥61%) accounted for 29. 43%; and other materials had waterlogging tolerance between the two. The identification results of waterlogging tolerance in the 349 rape germplasm resource from the upper,middle and lower reaches of Yangtze River and Huang-Huai Basin showed that materials from the lower Yangtze River had the lowest average dead seedling rate of 38. 8%,which was remarkably lower than materials from other ecological regions,and waterlogging-tolerant materials among them accounted for 33. 6%,which was also remarkably higher than materials from other ecological regions. It could thus be seen that materials from the lower Yangtze River have stronger waterlogging tolerance than those from other ecological regions overall. In this study,24 highly-tolerant B. napus germplasms( dead seedling rate < 1%) were selected from the 608 B. napus germplasm materials,which could be used for breeding of waterlogging-tolerant rape and related fundamental research.展开更多
A field trial was conducted to study the impact of various potato germplasm against aphids, Myzus persicae (Sulzer) and Aphis gossypii Glover (Aphididae: Hemiptera) during rabi season from November to March in 2012-20...A field trial was conducted to study the impact of various potato germplasm against aphids, Myzus persicae (Sulzer) and Aphis gossypii Glover (Aphididae: Hemiptera) during rabi season from November to March in 2012-2013 and 2013-2014, respectively at Adisaptagram Block Seed Farm, Hooghly, West Bengal. The population of aphids was started on potato crop in between third week of December and first week of January irrespective of various germplasms, except K. Chipsona-2, where its infestation was initiated during second and third week of January. Then, their population was gradually increased to reach its critical level (ETL) during first and second week of January in most of the potato germplasm, except in K. Anand, K. Chipsona-1, K. Chipsona-2 and Sailaja, where it was crossed in between fourth week of January and first week of February. The peak population of aphids was observed during third and fourth week of February in most of the potato germplasm. It was observed that K. Ashoka, K. Badshah, K. Chandramukhi, K. Jawahar, K. Jyoti and K. Pukhraj were highly susceptible to the pests, while K. Anand and K. Sutlez were moderately susceptible but K. Chipsona-1 , K. Chipsona-2 and K. Sailaja were less susceptible or tolerant to the pests. Maximum tuber yield (t/ha) of potato was recorded in K. Badshah (36.58 - 43.92) while it was lowest in K. Chandramukhi (22.08 - 22.12).展开更多
[ Objective] This study aimed to establish an appropriate technology system for in vitro screening of Fuzarium wilt-resistant germplasm resources of red edible seed watermelon and obtain variants resistant to fusaric ...[ Objective] This study aimed to establish an appropriate technology system for in vitro screening of Fuzarium wilt-resistant germplasm resources of red edible seed watermelon and obtain variants resistant to fusaric acid, thus providing resistant materials for breeding Fusarium wilt-resistant red edible seed watermel- on. [ Method] Using Zhongxin No. 1 red edible seed watermelon advemitious buds as screening materials and fusaric acid （FA） as a stress agent, in vitro screen- ing of Fusarium wilt-resistant red edible seed watermelon clonal variants and identification of Fusarium wilt-resistance of the germplasm resources of red edible seed watermelon were performed. [ Result] The results showed that the appropriate FA for in vitro screening of Fusarium wilt-resistant red edible seed watermelon vari- ants was 15 mg/L. In vitro screening system for Fusarium wilt-resistant red edible seed watermelon variants was established preliminarily and FA-resistant regenera- ted plants were obtained. Among the 36 germplasm resources of red edible seed watermelon, there were 2 highly resistant materials, 6 moderately resistant materi- als, 11 slightly resistant materials and 17 highly susceptible materials. [ Conclusion] This study confirmed preliminarily that in vitro screening method is effective for obtaining resistant materials of red edible seed watermelon.展开更多
Genetic<span style="font-family:;" "=""><span style="font-family:Verdana;"> variation between naturally occurring ecotypes can be helpful to elucidate the mechanism contr...Genetic<span style="font-family:;" "=""><span style="font-family:Verdana;"> variation between naturally occurring ecotypes can be helpful to elucidate the mechanism controlling salt stress response in different environments. The salt stress response of 20 natural accessions or cultivars of </span><i><span style="font-family:Verdana;">Lycium</span></i><span style="font-family:Verdana;"> was characterized at a physiological level, following exposed to 300 mM NaCl for 15 days. It is shown that salt stress increased Na</span><sup><span style="font-family:Verdana;">+</span></sup><span style="font-family:Verdana;">, betaine and malondialdehyde (MDA) content, as well as the relative permeability of plasma membranes, but decreased K</span><sup><span style="font-family:Verdana;">+</span></sup><span style="font-family:Verdana;">, chlorophyll and glutathione (GSH) content, as well as K</span><sup><span style="font-family:Verdana;">+</span></sup><span style="font-family:Verdana;">/Na</span><sup><span style="font-family:Verdana;">+</span></sup><span style="font-family:Verdana;"> ratio compared with their respective control value in most of the varieties, though the increasing or decreasing extent has a clear genetic diversity. The physiological response was utilized to evaluate the salt-tolerant capacity of these varieties by principal component analysis and clustering analysis, and in which total chlorophyll, K</span><sup><span style="font-family:Verdana;">+</span></sup><span style="font-family:Verdana;">/Na</span><sup><span style="font-family:Verdana;">+</span></sup><span style="font-family:Verdana;"> ratio and partially GSH have the maximum weight relatively. These varieties could be categorized into four sub-groups, means greatly resistance (Heiguo, Ninqi No. 2 and Beifang), moderately resistant, sensitive, and mostly sensitive (Ninqi No. 7) to salt stress. Our results provide a theoretical basis and practical guidance for the </span><span><span style="font-family:Verdana;">improvement of saline-alkali land and rational utilization of </span><i><span style="font-family:Verdana;">Lycium</span></i></span><span style="font-family:Verdana;"> germplasm resources in the future.</span></span>展开更多
Soybean rust caused by Phakopsora pachyrhizy is an important disease of soybean, and yield losses are very common in humid growing regions. Most commercial cultivars are susceptible and the disease is usually...Soybean rust caused by Phakopsora pachyrhizy is an important disease of soybean, and yield losses are very common in humid growing regions. Most commercial cultivars are susceptible and the disease is usually managed with fungicides. Resistance breeding is the most effective in controlling the disease. In this study, detached - leaf assay and greenhouse inoculation were used to screen 200 Glycine soja accessions for resistance to Phakopsora pachyrhizi in China. Most of the accessions were susceptible, and W8214 was the only accession that demonstrated RB resistance to Phakopsora pachyrhizy. The further repeated tests confirmed the resistance in W8214.展开更多
We genotyped 74 rice germplasms including Tripura＇s local landraces, improved varieties, cultivars and breeding lines and other rice varieties using molecular markers for genetic diversity, drought QTLs, and blast re...We genotyped 74 rice germplasms including Tripura＇s local landraces, improved varieties, cultivars and breeding lines and other rice varieties using molecular markers for genetic diversity, drought QTLs, and blast resistance genes. The number of alleles per locus ranged from 2 to 5 with an average of 2.9. The polymorphic information content value per locus ranged from 0.059（RM537） to 0.755（RM252） with an average of 0.475. Cluster analysis based on 30 simple sequence repeat markers revealed 5 clusters and also indicated the presence of variability within the rice accessions. The drought QTL q DTY2.1 was found in 56.0% of germplasms and q DTY1.1 was detected in only 6.8% of the germplasms. Out of seven rice blast resistance genes screened, only two rice varieties, RCPL-1-82 and Buh Vubuk（Lubuk）, were positive for four blast resistance genes while only Releng possessed two blast resistance genes. Among 74 rice germplasms, only three accessions, Releng, RCPL1-82 and Buh Vubuk（Lubuk）, possessed both drought-related QTLs and blast resistance genes. Overall, the 74 indigenous rice genotypes showed low level of genetic diversity, which is in contrast to high level of genetic diversity among rice varieties in northeast India, where highlights the good farming practice, conservation of germplasms and the limitation of molecular markers employed in this study. The presence of both drought related QTLs and blast resistance genes in some of the germplasms can be useful in future breeding programmes.展开更多
基金the Special NationalPrograms for Pioneer Research(Projecn No.2002CCA04100)Zhejiang Provincial Key Programs for Scicnce and Technology(Project No.021102169)Natural Sciences Foundation of Zhejiang Province(Project No.301252).
文摘The lengths of mesocotyl in the seedlings of 84 lowland rice varieties and 12 upland rice varieties were measured following the treatments of daylight and darkness during germination. The elongation of mesocotyl in the varieties tested was inhibited under daylight condition, and the mesocotyl of all the varieties elongated variably under darkness condition. The elongated lengths of the mesocotyl in upland rice, ranging from 0.36 cm to 1,61 cm with an average of 0.81 cm, was obviously longer than those in lowland rice, ranging from 0.12 cm to 1.56 cm with an average of 0.42 cm. Among 14 rice varieties with over 1 cm of mesocotyl length, five belonged to upland rice, and nine to lowland rice. The possible utilization of the elongated-mesocotyl rice germplasm in varietal imorovement, direct-seeded plantina and seed ouritv testina were discussed.
基金Supported by National Key Research and Development Program of China(2016YFD0100202-10)
文摘In order to evaluate,screen and identify waterlogging-tolerant Brassica napus resources and provide good germplasm materials for breeding of waterlogging-tolerant rape,608 B. napus germplasm materials from different sources were identified and screened for waterlogging-tolerant germplasms. The identification results showed that tested materials had dead seedling rates in the range of 0-100%,indicating that these rape germplasm materials varied extensively in waterlogging tolerance. Among the 608 materials,waterlogging-tolerant materials( grade I,relative dead seedling rate≤21%) accounted for 25. 49%; non-tolerant materials( grade Ⅳ + V,dead seedling rate≥61%) accounted for 29. 43%; and other materials had waterlogging tolerance between the two. The identification results of waterlogging tolerance in the 349 rape germplasm resource from the upper,middle and lower reaches of Yangtze River and Huang-Huai Basin showed that materials from the lower Yangtze River had the lowest average dead seedling rate of 38. 8%,which was remarkably lower than materials from other ecological regions,and waterlogging-tolerant materials among them accounted for 33. 6%,which was also remarkably higher than materials from other ecological regions. It could thus be seen that materials from the lower Yangtze River have stronger waterlogging tolerance than those from other ecological regions overall. In this study,24 highly-tolerant B. napus germplasms( dead seedling rate < 1%) were selected from the 608 B. napus germplasm materials,which could be used for breeding of waterlogging-tolerant rape and related fundamental research.
文摘A field trial was conducted to study the impact of various potato germplasm against aphids, Myzus persicae (Sulzer) and Aphis gossypii Glover (Aphididae: Hemiptera) during rabi season from November to March in 2012-2013 and 2013-2014, respectively at Adisaptagram Block Seed Farm, Hooghly, West Bengal. The population of aphids was started on potato crop in between third week of December and first week of January irrespective of various germplasms, except K. Chipsona-2, where its infestation was initiated during second and third week of January. Then, their population was gradually increased to reach its critical level (ETL) during first and second week of January in most of the potato germplasm, except in K. Anand, K. Chipsona-1, K. Chipsona-2 and Sailaja, where it was crossed in between fourth week of January and first week of February. The peak population of aphids was observed during third and fourth week of February in most of the potato germplasm. It was observed that K. Ashoka, K. Badshah, K. Chandramukhi, K. Jawahar, K. Jyoti and K. Pukhraj were highly susceptible to the pests, while K. Anand and K. Sutlez were moderately susceptible but K. Chipsona-1 , K. Chipsona-2 and K. Sailaja were less susceptible or tolerant to the pests. Maximum tuber yield (t/ha) of potato was recorded in K. Badshah (36.58 - 43.92) while it was lowest in K. Chandramukhi (22.08 - 22.12).
基金Supported by National Space Breeding Project of China(2006HT100113)China Agriculture Research System(CARS-26)Science and Technology Development Fund of Guangxi Academy of Agricultural Sciences(GNK2013YZ26)
文摘[ Objective] This study aimed to establish an appropriate technology system for in vitro screening of Fuzarium wilt-resistant germplasm resources of red edible seed watermelon and obtain variants resistant to fusaric acid, thus providing resistant materials for breeding Fusarium wilt-resistant red edible seed watermel- on. [ Method] Using Zhongxin No. 1 red edible seed watermelon advemitious buds as screening materials and fusaric acid （FA） as a stress agent, in vitro screen- ing of Fusarium wilt-resistant red edible seed watermelon clonal variants and identification of Fusarium wilt-resistance of the germplasm resources of red edible seed watermelon were performed. [ Result] The results showed that the appropriate FA for in vitro screening of Fusarium wilt-resistant red edible seed watermelon vari- ants was 15 mg/L. In vitro screening system for Fusarium wilt-resistant red edible seed watermelon variants was established preliminarily and FA-resistant regenera- ted plants were obtained. Among the 36 germplasm resources of red edible seed watermelon, there were 2 highly resistant materials, 6 moderately resistant materi- als, 11 slightly resistant materials and 17 highly susceptible materials. [ Conclusion] This study confirmed preliminarily that in vitro screening method is effective for obtaining resistant materials of red edible seed watermelon.
文摘Genetic<span style="font-family:;" "=""><span style="font-family:Verdana;"> variation between naturally occurring ecotypes can be helpful to elucidate the mechanism controlling salt stress response in different environments. The salt stress response of 20 natural accessions or cultivars of </span><i><span style="font-family:Verdana;">Lycium</span></i><span style="font-family:Verdana;"> was characterized at a physiological level, following exposed to 300 mM NaCl for 15 days. It is shown that salt stress increased Na</span><sup><span style="font-family:Verdana;">+</span></sup><span style="font-family:Verdana;">, betaine and malondialdehyde (MDA) content, as well as the relative permeability of plasma membranes, but decreased K</span><sup><span style="font-family:Verdana;">+</span></sup><span style="font-family:Verdana;">, chlorophyll and glutathione (GSH) content, as well as K</span><sup><span style="font-family:Verdana;">+</span></sup><span style="font-family:Verdana;">/Na</span><sup><span style="font-family:Verdana;">+</span></sup><span style="font-family:Verdana;"> ratio compared with their respective control value in most of the varieties, though the increasing or decreasing extent has a clear genetic diversity. The physiological response was utilized to evaluate the salt-tolerant capacity of these varieties by principal component analysis and clustering analysis, and in which total chlorophyll, K</span><sup><span style="font-family:Verdana;">+</span></sup><span style="font-family:Verdana;">/Na</span><sup><span style="font-family:Verdana;">+</span></sup><span style="font-family:Verdana;"> ratio and partially GSH have the maximum weight relatively. These varieties could be categorized into four sub-groups, means greatly resistance (Heiguo, Ninqi No. 2 and Beifang), moderately resistant, sensitive, and mostly sensitive (Ninqi No. 7) to salt stress. Our results provide a theoretical basis and practical guidance for the </span><span><span style="font-family:Verdana;">improvement of saline-alkali land and rational utilization of </span><i><span style="font-family:Verdana;">Lycium</span></i></span><span style="font-family:Verdana;"> germplasm resources in the future.</span></span>
文摘Soybean rust caused by Phakopsora pachyrhizy is an important disease of soybean, and yield losses are very common in humid growing regions. Most commercial cultivars are susceptible and the disease is usually managed with fungicides. Resistance breeding is the most effective in controlling the disease. In this study, detached - leaf assay and greenhouse inoculation were used to screen 200 Glycine soja accessions for resistance to Phakopsora pachyrhizi in China. Most of the accessions were susceptible, and W8214 was the only accession that demonstrated RB resistance to Phakopsora pachyrhizy. The further repeated tests confirmed the resistance in W8214.
文摘We genotyped 74 rice germplasms including Tripura＇s local landraces, improved varieties, cultivars and breeding lines and other rice varieties using molecular markers for genetic diversity, drought QTLs, and blast resistance genes. The number of alleles per locus ranged from 2 to 5 with an average of 2.9. The polymorphic information content value per locus ranged from 0.059（RM537） to 0.755（RM252） with an average of 0.475. Cluster analysis based on 30 simple sequence repeat markers revealed 5 clusters and also indicated the presence of variability within the rice accessions. The drought QTL q DTY2.1 was found in 56.0% of germplasms and q DTY1.1 was detected in only 6.8% of the germplasms. Out of seven rice blast resistance genes screened, only two rice varieties, RCPL-1-82 and Buh Vubuk（Lubuk）, were positive for four blast resistance genes while only Releng possessed two blast resistance genes. Among 74 rice germplasms, only three accessions, Releng, RCPL1-82 and Buh Vubuk（Lubuk）, possessed both drought-related QTLs and blast resistance genes. Overall, the 74 indigenous rice genotypes showed low level of genetic diversity, which is in contrast to high level of genetic diversity among rice varieties in northeast India, where highlights the good farming practice, conservation of germplasms and the limitation of molecular markers employed in this study. The presence of both drought related QTLs and blast resistance genes in some of the germplasms can be useful in future breeding programmes.
