Increased yield performance of mutation induced Soybean genotypes at varied agro-ecological conditions

Abstract In soybean breeding program, continuous selection pressure on traits response to yield created a genetic bottleneck for improvements of soybean through hybridization breeding technique. Therefore an initiative was taken to developed high yielding soybean variety applying mutation breeding techniques at Plant Breeding Division, Bangladesh Institute of Nuclear Agriculture (BINA), Bangladesh. Locally available popular cultivar BARI Soybean-5 was used as a parent material and subjected to five different doses of Gamma ray using Co60. In respect to seed yield and yield attributing characters, twelve true breed mutants were selected from M4 generation. High values of heritability and genetic advance with high genotypic coefficient of variance (GCV) for plant height, branch number and pod number were considered as favorable attributes for soybean improvement that ensure expected yield. The mutant SBM-18 obtained from 250Gy provided stable yield performance at diversified environments. It provided maximum seed yield of 3056 kg ha-1 with highest number of pods plant-1 (56). The National Seed Board of Bangladesh (NSB) eventually approved SBM-18 and registered it as a new soybean variety named Binasoybean-5 for large-scale planting because of its superior stability in various agro-ecological zones and consistent yield performance.

Resumo No programa de melhoramento da soja, a pressão pela seleção contínua para a resposta das características de rendimento criou um gargalo genético para melhorias da soja por meio da técnica de melhoramento por hibridação. Portanto, foi desenvolvida uma variedade de soja de alto rendimento, aplicando técnicas de reprodução por mutação, na Divisão de Melhoramento de Plantas, no Instituto de Agricultura Nuclear de Bangladesh (BINA), em Bangladesh. A cultivar popular BARI Soybean-5, disponível localmente, foi usada como material original e submetida a cinco doses diferentes de raios gama usando Co60. Em relação ao rendimento de sementes e às características de atribuição de rendimento, 12 mutantes genuínos foram selecionados a partir da geração M4. Altos valores de herdabilidade e avanço genético com alto coeficiente de variância genotípico (GCV) para altura da planta, número de ramos e número de vagens foram considerados atributos favoráveis ao melhoramento da soja, garantindo, assim, a produtividade esperada. O mutante SBM-18, obtido a partir de 250Gy, proporcionou desempenho de rendimento estável em ambientes diversificados e produtividade máxima de sementes de 3.056 kg ha-1 com o maior número de vagens planta-1 (56). O Conselho Nacional de Sementes de Bangladesh (NSB) finalmente aprovou o SBM-18 e o registrou como uma nova variedade de soja, chamada Binasoybean-5, para plantio em larga escala por causa de sua estabilidade superior em várias zonas agroecológicas e desempenho de rendimento consistente.

Increased yield performance of mutation induced Soybean genotypes at varied agro-ecological conditions / Aumento no desempenho de rendimento de genótipos de soja induzidos por mutação em condições agroecológicas variadas

Abstract In soybean breeding program, continuous selection pressure on traits response to yield created a genetic bottleneck for improvements of soybean through hybridization breeding technique. Therefore an initiative was taken to developed high yielding soybean variety applying mutation breeding techniques at Plant Breeding Division, Bangladesh Institute of Nuclear Agriculture (BINA), Bangladesh. Locally available popular cultivar BARI Soybean-5 was used as a parent material and subjected to five different doses of Gamma ray using Co60. In respect to seed yield and yield attributing characters, twelve true breed mutants were selected from M4 generation. High values of heritability and genetic advance with high genotypic coefficient of variance (GCV) for plant height, branch number and pod number were considered as favorable attributes for soybean improvement that ensure expected yield. The mutant SBM-18 obtained from 250Gy provided stable yield performance at diversified environments. It provided maximum seed yield of 3056 kg ha-1 with highest number of pods plant-1 (56). The National Seed Board of Bangladesh (NSB) eventually approved SBM-18 and registered it as a new soybean variety named 'Binasoybean-5' for large-scale planting because of its superior stability in various agro-ecological zones and consistent yield performance.

Resumo No programa de melhoramento da soja, a pressão pela seleção contínua para a resposta das características de rendimento criou um gargalo genético para melhorias da soja por meio da técnica de melhoramento por hibridação. Portanto, foi desenvolvida uma variedade de soja de alto rendimento, aplicando técnicas de reprodução por mutação, na Divisão de Melhoramento de Plantas, no Instituto de Agricultura Nuclear de Bangladesh (BINA), em Bangladesh. A cultivar popular BARI Soybean-5, disponível localmente, foi usada como material original e submetida a cinco doses diferentes de raios gama usando Co60. Em relação ao rendimento de sementes e às características de atribuição de rendimento, 12 mutantes genuínos foram selecionados a partir da geração M4. Altos valores de herdabilidade e avanço genético com alto coeficiente de variância genotípico (GCV) para altura da planta, número de ramos e número de vagens foram considerados atributos favoráveis ​​ao melhoramento da soja, garantindo, assim, a produtividade esperada. O mutante SBM-18, obtido a partir de 250Gy, proporcionou desempenho de rendimento estável em ambientes diversificados e produtividade máxima de sementes de 3.056 kg ha-1 com o maior número de vagens planta-1 (56). O Conselho Nacional de Sementes de Bangladesh (NSB) finalmente aprovou o SBM-18 e o registrou como uma nova variedade de soja, chamada 'Binasoybean-5', para plantio em larga escala por causa de sua estabilidade superior em várias zonas agroecológicas e desempenho de rendimento consistente.

60Co-γ Radiation-induced Population Variation and Cluster Analysis of M1 Generation of Andrographis paniculata / 中国药房

OBJECTIVE： To study the effects of 60Co-γ radiation on the botanical traits and property of Andrographis paniculata， and to screen suitable irradiation dose. METHODS： The seeds of A. paniculata were irradiated by 60Co-γ rays with different irradiation doses（0，10，20，50，100，200，300 Gy）. The botanical traits indexes of A. paniculata as seed germination rate， root length， seedling rate， seedling height， leaf area， fresh weight， dry weight， stomata number of lower epidermis of leaf， and its property indexes as the contents of andrographolide， dehydrated andrographolide and chlorophyll， activity of T-SOD enzyme and CuZn-SOD enzyme， were determined after radiation. The coefficient of variation （CV） was calculated. The linear regression analysis was performed for seedling rate， and medial lethal dose was calculated. The correlation analysis was performed between the parameters of botanical trait and quality property with irradiation dose. Cluster analysis was conducted for M1 generation of A. paniculata in different irradiation dose groups by connection method combined with squared euclidean distance. RESULTS： Different irradiation doses showed different effects on botanical traits and property of A. paniculata. According to the average value of CV， the index of botanical traits was ranked as leaf area ＞ fresh weight ＞ dry weight ＞ plant height ＞ root length ＞ stomata number ＞ seedling rate ＞ germination rate； among different irradiation dose groups， the coefficient of variation was ranked as 50 Gy＞200 Gy＞100 Gy＞20 Gy＞10 Gy＞300 Gy＞0 Gy. According to the average value of CV， the index of property was ranked as dehydrated andrographolide content＞andrographolide content＞chlorophyll content＞CuZn-SOD enzyme activity＞T-SOD enzyme activity； among different irradiation dose groups， the coefficient of variation was ranked as 100 Gy＞50 Gy＞200 Gy＞20 Gy＞10 Gy＞300 Gy＞0 Gy. The medial lethal dose was 195.10 Gy. According to the botanical traits， M1 generation of A. paniculata of 7 dose groups could be divided into 4 types. According to the property， M1 generation of A. paniculata of 7 dose groups could be divided into 3 types. CONCLUSIONS： The suitable irradiation dose interval for irradiating A. paniculata is 50-200 Gy.

Genotyping-by-sequencing based single nucleotide polymorphisms enabled Kompetitive Allele Specific PCR marker development in mutant Rubus genotypes

Background: Rubus is an economically important fruit crop across the globe. Recently, several Rubus mutant genotypes with improved agronomic traits have been developed using gamma ray irradiation. This study investigated genetic diversity and variations in Rubus mutant genotypes using single nucleotide polymorphism (SNP) markers generated from genotyping-by-sequencing (GBS) analysis. A GBS library of 14 Rubus genotypes, consisting of seven boysenberry mutant lines, four blackberry mutant lines, and three original varieties, were sequenced on the Illumina Hiseq2000 platform. A set of SNPs were analyzed by Kompetitive Allele Specific PCR (KASP) assay in order to discriminate the Rubus genotypes. Results: A total of 50,831,040 (86.4%) reads of clean data were generated, and the trimmed length ranged from 116,380,840 to 509,806,521 bp, with an average of 228,087,333 bp per line. A total of 19,634 high-quality SNPs were detected, which contained 11,328 homozygous SNPs and 8306 heterozygous SNPs. A set of 1504 SNPs was used to perform a phylogenetic analysis, which showed that there were clear differences among the Rubus genotypes based on their origin. A total of 25 SNPs were used for the KASP assays, of which six KASP primer sets were successfully distinguished among the Rubus genotypes. Conclusions: This study demonstrated that the SNP and KASP method is an economically efficient tool for mutant screening in Rubus breeding programs.

Selection of Schizochytrium limacinum mutants based on butanol tolerance

Background: Mutation breeding is one of the most important routes to achieving high docosahexaenoic acid (DHA) productivity using Schizochytrium. However, few selection strategies have been reported that aim to generate a high DHA content in Schizochytrium lipids. Results: First, culture temperature altered the butanol tolerance of Schizochytrium limacinum B4D1. Second, S. limacinum E8 was obtained by selecting mutants with high butanol tolerance. This mutant exhibited a 17.97% lower proportion of DHA than the parent strain S. limacinum B4D1. Third, a negative selection strategy was designed in which S. limacinum F6, a mutant with poor butanol tolerance, was obtained. The proportion of DHA in S. limacinum F6 was 11.22% higher than that of parent strain S. limacinum B4D1. Finally, the performances of S. limacinum B4D1, E8 and F6 were compared. These three strains had different fatty acid profiles, but there was no statistical difference in their biomasses and lipid yields. Conclusion: It was feasible to identified the relative DHA content of S. limacinum mutants based on their butanol tolerance.

Screening of ?-Rhamnosidase High-yield Strain from Aspergillus niger / 微生物学通报

In this study, plate transparent circle by Davis method was introduce firstly screening ?-Rhamnosidase high-yield strain. The spore-sprouted Aspergillus niger 8-hour were mutagenized by ethyl methane sulphonate and pre-screened via transparent circle. 11% mutants yield 40% higher of ?-rhamnosidase than the original strain. A high-yield strain, T-226 with the highest ?-rhamnosidase activity of 373.4 U/mL was finally selected from these potential high-yield mutants after rescreened by shake flask fermentation twice. When the T-226 strain was fermented in 5 L bioreactor, the enzyme activity could reach to 631.9 U/mL after 84 h. Thus, the established screening method is highly efficient to isolate ?-rhamnosidase high-yield mutant of A. niger.

The Strategy of Citrinin Production Control in Monascus / 中国生物工程杂志

Pepole pay more attention to the medicinal value and health function of Monascus day by day,however,the existence of citrinin restricted the further development of Monascus products heavily. How to ruduce the content of citrinin is a problem need to be solved urgently.Briefly introduced the toxicity,the biosynthetic pathway,and the relative standards of citrinin in monascus. According to the research progress on citrinin,the strategies of citrinin control were described from the three aspects of fermentation technology,mutation breeding,and genetic engineering. The expectation about the direction of citrinin in the future was also discussed.

Ultraviolet Mutation Breeding Aspect of the Biological Control of Postharvest Diseases by Kloeckera apiculata in Citrus Fruit / 微生物学通报

A series of experiments were conducted to study the mutation of Kloechera apiculata by many kinds of treatments such as UV and UV+LiCl.The optimal dosage disposal was determined:15 W 30 cm under Ultraviolet irradiation for 20 s,UV+LiCl under Ultraviolet irradiation for 20 s and added LiCl 0.3% (w/v).One strain(UV20-13)which had obvious physiological characteristic was obtained.the incidence of blue and green mold of citrus was reduced by 25.56%and 10.00%in vivo experiment after 7 days respectively. The strain UV20-13 was tested by the experiments of subculture and dynamic growth,and the results showed that the strain UV20-13 was better than K.apiculata in the growth characteristics,and it did not appear retrogression,reversion mutation ect after subculturing 10 generations.Therefore the strain UV20-13 had genetic stability.

Study on Breeding of High-yield Avilamycin-producing Strains by Nitrogen Ion Implantation / 微生物学通报

To obtain high-yield avilamycin-producing strains,low energy N~+ ion implantation technology and screening of streptomycin-re- sistant mutants are used in the study on breeding mutation.The results show that,“saddle”region,which range is from 3?10~(15) to 5?10~(15) ions/cm~2,has got better induced mutation action.It also means that the strain's resistant mutation and yield mutation closely correlate to each other,and the method of streptomycin resistant screening is feasible.We have isolated a high-yield strain SVT-45 which the productivi- ty is 195% higher than the original strain's in the rotation-flask experiments.These results showed that the ion implantation was an effective method for microbe mutagensis.