Comparative studies on seed protein characteristics in eight lines of two Gossypium species

[Abstract]
Background: In order to achieve the targets aiming at the improvement of protein quality, knowledge regarding seed protein fractions and polypeptides constituting them in different crops is essential. Besides having high nutritional value as animal feed and human food, the protein isolates from cottonseed meal have also been proven promising as industrial raw materials for a number of applications. As far as Indian work on the characterization of cotton seed proteins is concerned, relatively meagre reports are available. Keeping in mind the importance of cotton seed proteins, lines belonging to Gossypium arboreum L. (Indian cotton) and G. hirsutum L. (American cotton) which are grown in all the major cotton growing states in India were selected for analysing their seed protein characteristics.

Results: Whereas G. arboreum (A-genome) lines revealed a lower range of seed protein content i.e. 19.5~24.3%, an upper range (21.8~29.5%) could be observed in lines of G. hirsutum (AD-genome). Globulins represented dominating fraction in both species followed by albumins, glutelins and prolamins. A significant positive correlation between albumins/globulins and seed protein content in G. arboreum /G. hirsutum, respectively, was observed. Intraspecific electrophoretic variation in seed protein extracts was observed in the region of molecular weight 22 kDa – 27 kDa in lines of both the species; however some lines with A-genome showed similarity in banding pattern with AD-genome. Four polypeptides with disulphide-linkages were also reported for the first time. Albumins were observed to reveal more variations in their electrophoretic pattern between the lines of two species followed by globulins.

Conclusion: On the basis of present and previous studies, screening the lines with low or high protein content will lead the selection of lines with superior polypeptide fraction important for nutritional and industrial purposes. On comparing the composition and behaviour of four 2-S linked polypeptides with other plant groups, these were suggested to be legumin-like in nature. The similarity in banding patterns between the lines of A-genome and AD-genome species marked towards the close evolutionary relationship between these two. Albumin fractions on the basis of our results could be taken for cultivar differentiation in cotton crop.

[Keywords]
Gossypium, SDS-PAGE, Seed proteins, Globulins

Original text: https://jcottonres.biomedcentral.com/articles/10.1186/s42397-019-0024-3

[Authors] SINGH Arvinder, KAUR Amanjot

JCR-Physiology and Pathology Thematic Series Call For Paper

Coordinator:
Professor Hezhong DONG, Cotton Research Centre, Shandong Academy of Agricultural Sciences, China;
Professor Zhiguo ZHOU, Nanjing Agricultural University, China

Journal of Cotton Research is hosting a thematic series on cotton physiology and pathology. The research community is encouraged to share original findings, methodology, results, databases, and/or software and opinions.

Scopes that may be covered in the submissions may include, but are not limited to the following:

1. growth and organ development;
2. plant and shoot architecture;
3. water, fertilizer, light, etc. use efficiency;
4. intelligent agriculture;
5. rhizosphere and other plant-environment interactions;
6. main disease and resistance.

Submission Deadline: 30 September 2019

Submit Now

https://jcottonres.biomedcentral.com/cottonpap

Evaluation of genetic diversity in short duration cotton (Gossypium hirsutum L.)

[Background] Cotton (Gossypium hirsutum L.) is an important fiber crop in Bangladesh. Genetic diversity among the genotypes of a germplasm has a great importance for cotton breeding. An experiment was carried out at the experimental field of Cotton Research, Training and Seed Multiplication Farm, Sreepur, Gazipur during the cropping season of 2015–2016 with 100 genotypes to evaluate genetic diversity of cotton genotypes for short duration using field performance.

[Results] The genotypes under study were grouped into ten clusters through multivariate analysis using GENSTAT-5. Cluster III contained maximum number of genotypes (16) while cluster X contained the least number of genotypes (7). The inter cluster distances were larger than intra cluster distances in all cases suggesting wider genetic diversity among the genotypes of different clusters. The maximum and minimum inter cluster distances were observed between clusters II and V (10.78) and clusters VIII and IX (3.30), respectively. The results indicated diverse and close relationship among the genotypes of those clusters. Earliness index, single boll weight and days to boll opening showed the higher contribution to the genetic divergence among 19 characters.

[Conclusion] Based on the results of genetic diversity and earliness index, the genotypes from cluster II could be used as parent in hybridization program for the development of short duration cotton variety.

Evaluation of genetic diversity in short duration cotton (Gossypium hirsutum L.)

AKTER T., ISLAM A. K. M. A., RASUL M. G., KUNDU S., KHALEQUZZAMAN and AHMED J. U.
Journal of Cotton Research. 2019; 2:1.
https://doi.org/10.1186/s42397-018-0018-6

Irrigation’s effect and applied selection on the fiber quality of Ethyl MethaneSulfonate (EMS) treated upland cotton (Gossypium hirsutum L.)

[Background] Producing rainfed cotton (Gossypium hirsutum L.) with high fiber quality has been challenging in the Texas High Plains because of extended periods of insufficient rainfall during sensitive boll developmental stages. Genetic variation created by Ethyl MethaneSulfonate (EMS) mutagen has successfully improved fiber quality of cotton. However, little is known about the effect of water deficit environments on fiber quality. Three EMS treated populations were advanced from the first to the fourth generation (M1 to M4) as bulk harvested populations. In 2014, single-plant divergent selection was applied based on perceived morphological and agronomic differences seen during and at the end of the season.

[Results] Analyses from these selections in 2014–2016 showed significant (P < 0.05) improvement between and within populations for fiber traits (micronaire, length, strength, uniformity, and elongation) when compared with the original non-treated EMS source; some selections were found to have excellent fiber quality under diverse irrigation-regimes.

[Conclusions] Some of these selections are being considered for germplasm release and could be useful for improving the fiber quality of cotton under water limited conditions, thereby helping to ensure the long-term survival of the cotton industry on the Texas High Plains.

Irrigation’s effect and applied selection on the fiber quality of Ethyl MethaneSulfonate (EMS) treated upland cotton (Gossypium hirsutum L.)
WITT Travis W. , ULLOA Mauricio, PELLETIER Mathew G. , MENDU Venugopal and RITCHIE Glen L.
Journal of Cotton Research. 2018; 1:17.
https://jcottonres.biomedcentral.com/articles/10.1186/s42397-018-0016-8

JCR-Cotton High Speed Phenotyping Thematic Series Call For Paper

Journal of Cotton Research

Cotton High Speed Phenotyping
Thematic Series Call For Paper
Coordinator: Professor Eric F. Hequet, Texas Tech University, USA; Dr. Glen Ritchie, Texas Tech University, USA

Author’s allowance: The sponsor, Institute of Cotton Research, CAAS, grants to cover not only APC for the submission, but also the author’s allowance once published.

High speed phenotyping is critical to improve cotton research and production. It can be applied to large scale commercial fields, research fields, breeding lines, and even at the individual plant level. The main goals are to improve yield, fiber quality, stress and disease resistance, etc… Recently, advances in high speed phenotyping in cotton have been achieved. The Journal of Cotton Research is hosting a thematic series on this topic. The research community is encouraged to share original findings, methodology, results, databases, and/or software and opinions.

Scopes that may be covered in the submissions may include, but are not limited to the following:
1. Platform design: air-based and/or land-based;
2. Data capture and processing: sensors (RGB, IR, multispectral, sonic, etc.), integration of multiple sensors, information processing technologies;
3. Data analysis and Metadata: analysis of very large data sets, validation with ground truth, practical application examples (breeding programs, site specific irrigation scheduling, etc.).

Submission Deadline: April 30, 2019

https://jcottonres.biomedcentral.com/cottonhsp

Genetic diversity and population structure of Gossypium arboreum L. collected in China

[Background] Gossypium arboreum is a diploid species cultivated in the Old World. It possesses favorable characters that are valuable for developing superior cotton cultivars.

[Method] A set of 197 Gossypium arboreum accessions were genotyped using 80 genome-wide SSR markers to establish patterns of the genetic diversity and population structure. These accessions were collected from three major G. arboreum growing areas in China. A total of 255 alleles across 80 markers were identified in the genetic diversity analysis.

[Results] Three subgroups were found using the population structure analysis, corresponding to the Yangtze River Valley, North China, and Southwest China zones of G. arboreum growing areas in China. Average genetic distance and Polymorphic information content value of G. arboreum population were 0.34 and 0.47, respectively, indicating high genetic diversity in the G. arboreum germplasm pool. The Phylogenetic analysis results concurred with the subgroups identified by Structure analysis with a few exceptions. Variations among and within three groups were observed to be 13.61% and 86.39%, respectively.

[Conclusion] The information regarding genetic diversity and population structure from this study is useful for genetic and genomic analysis and systematic utilization of economically important traits in G. arboreum.

Genetic diversity and population structure of Gossypium arboreum L. collected in China
JIA Yinhua, PAN Zhaoe, HE Shoupu, GONG Wenfang, GENG Xiaoli, PANG Baoyin, WANG Liru and DU Xiongming
Journal of Cotton Research. 2018; 1:11.
https://doi.org/10.1186/s42397-018-0011-0

Map-based cloning of a recessive gene v1 for virescent leaf expression in cotton (Gossypium spp.)

[Background] Virescence, as a recognizable phenotype in the early development stage of cotton, is not only available for research on chloroplast development and photosynthesis but also for heterosis exploitation in cotton.

[Methods] In current study, for fine mapping of virescent-1 (v1) in cotton, three populations with a total of 5 678 individuals were constructed using T582 which has the virescent trait. Tobacco rattle virus, TRV1 and TRV2 (pYL156), were used as vectors for the virus-induced gene silencing (VIGS) assay.

[Results] The v1 gene was fine-mapped to a 20 kb interval on chromosome 20 of tetraploid cotton. We identified only one candidate gene with four single nucleotide polymorphisms between parents, among which the single nucleotide polymorphism at the position of 1 082 base pair caused the change of amino acid residue from Arg (3–79) to Lys (T582). The relative expression of the candidate gene in virescent plants was extensively lower than that in normal plants. Nullification of the gene by VIGS significantly turned the green leaf of normal cotton plants into yellow. We named this candidate gene as GhRVL.

[Conclusions] This study will facilitate the further research on virescent formation, and will be useful for breeding of hybrid cottons.

Map-based cloning of a recessive gene v1 for virescent leaf expression in cotton (Gossypium spp.)
ZHANG Youping, WANG Qiaolian, ZUO Dongyun, CHENG Hailiang, LIU Ke, ASHRAF Javaria, LI Simin, FENG Xiaoxu, YU John Z. and SONG Guoli
Journal of Cotton Research. 2018; 1:10.
https://doi.org/10.1186/s42397-018-0009-7

Identification and screening of nitrogen-efficient cotton genotypes under low and normal nitrogen environments at the seedling stage

[Background] Large quantities of nitrogen (N) fertilizer applied to cotton cropping systems support high yields but cause adverse environmental impacts such as N2O emission and water eutrophication. The development of cotton cultivars with higher N use efficiencies suitable for low-N conditions is therefore important for sustainable production. In this study, we evaluated 100 cotton genotypes in 2016 for N use efficiency and related traits at the seedling stage.

[Methods] Sand culture experiment was conducted with low N levels (0.01 g·kg−1) or normal N levels (0.1 g·kg−1). We investigated plant height, SPAD value (soil plant analysis development chlorophyll meter), dry weight, N accumulation, N utilization efficiency, and N uptake efficiency. Through descriptive statistics, principal component analysis and heatmap clustering analysis, we confirmed the evaluation index system of N-efficient genotypes and the classification of N-efficient genotypes.

[Results] Significant differences were observed among N levels and genotypes for all agronomic traits and N levels. Coefficients of variation varied greatly and ranged from 6.7~28.8 and 7.4~20.8 under low-N and normal-N treatment, respectively. All traits showed highly significant positive correlations with each other, except SPAD value. The principal components under both N levels were similar, showing that total dry weight, aboveground dry weight, total N accumulation, and N uptake efficiency were important components. We confirmed these four traits as suitable screening indexes for low N tolerance. Based on the results of heatmap clustering and scatter diagram analysis of N efficiency value, 10 genotypes were found low-N tolerant, in which five varieties were inefficient under both low and normal N conditions, while four varieties were found efficient under low-N conditions but inefficient under normal-N conditions. Only one variety was efficient under both low and normal-N conditions. Meanwhile, 20 genotypes were identified as low-N sensitive ones, in which 19 genotypes were inefficient under low-N conditions but efficient under normal-N conditions, one variety was inefficient under both low and normal-N conditions.

[Conclusion] We preliminarily identified Kashi as a low-N tolerant and N-efficient cotton genotype, and CCRI 64 as a low-N sensitive and N-inefficient cotton genotype. Further studies should be carried out to verify the yield and heritability effect of specific genotypes in the field.

Identification and screening of nitrogen-efficient cotton genotypes under low and normal nitrogen environments at the seedling stage
ZHANG Hengheng†, FU Xiaoqiong†, WANG Xiangru, GUI Huiping, DONG Qiang, PANG Nianchang, WANG Zhun, ZHANG Xiling and SONG Meizhen
†Contributed equally
Journal of Cotton Research. 2018; 1:6.
https://jcottonres.biomedcentral.com/articles/10.1186/s42397-018-0006-x

Analysis of short fruiting branch gene and Marker-assisted selection with SNP linked to its trait in upland cotton

[Background] With the rapid development of genomics, many functional genes have been targeted. Molecular marker assisted selection can accelerate the breeding process by linking selection to functional genes.

[Methods] In a study of upland cotton (Gossypium hirsutum L.), the F2 segregated population was constructed by crossing X1570 (short branches) with Ekangmian-13 (long branches) to identify the short fruiting branch gene and marker-assisted selection with SNP(Single Nucleotide Polymorphisms, SNP) linked to its trait.

[Result] The result demonstrated that linked SSR marker BNL3232 was screened by BSA(Bulked segregant analysis, BSA) method; one SNP locus was found, which was totally separated from the fruiting branches trait in upland cotton.

[Conclusion] It was verified that this SNP marker could be used for molecular assisted selection of cotton architecture.

Analysis of short fruiting branch gene and Marker-assisted selection with SNP linked to its trait in upland cotton
ZHANG Youchang, FENG Changhui, BIE Shu, WANG Xiaogang, ZHANG Jiaohai, XIA Songbo and QIN Hongde
Journal of Cotton Research. 2018; 1:5.
https://doi.org/10.1186/s42397-018-0001-2

The current status of nitrogen fertiliser use efficiency and future research directions for the Australian cotton industry

Fifty years of sustained investment in research and development has left the Australian cotton industry well placed to manage nitrogen (N) fertiliser. The average production in the Australian cotton industry today is greater than two tonnes of lint per hectare due to improved plant genetics and crop management. However, this average yield is well below the yield that would be expected from the amount of N fertiliser used. It is clear from the recent studies that across all growing regions, conversion of fertiliser N into lint is not uniformly occurring at application rates greater than 200–240 kg·hm−2 of N. This indicates that factors other than N availability are limiting yield, and that the observed nitrogen fertiliser use efficiency (NFUE) values may be caused by subsoil constraints such as sodicity and compaction. There is a need to investigate the impact of subsoil constraints on yield and NFUE. Gains in NFUE will be made through improved N fertiliser application timing, better targeting the amount of fertiliser applied for the expected yield, and improved soil N management. There is also a need to improve the ability and confidence of growers to estimate the contribution of soil N mineralisation to the crop N budget. Many Australian studies including data that could theoretically be collated in a meta-analysis suggest relative NFUE values as a function of irrigation technique; however, with the extensive list of uncontrolled variables and few studies using non-furrow irrigation, this would be a poor substitute for a single field-based study directly measuring their efficacies. In irrigated cotton, a re-examination of optimal NFUE is due because of the availability of new varieties and the potential management and long-term soil resilience implications of the continued removal of mineralised soil N suggested by high NFUE values. NFUE critical limits still need to be derived for dryland systems.

The current status of nitrogen fertiliser use efficiency and future research directions for the Australian cotton industry
MACDONALD Ben C. T., LATIMER James O., SCHWENKE Graeme D., NACHIMUTHU Gunasekhar and BAIRD Jonathan C.
Journal of Cotton Research. 2018; 1:15.
https://doi.org/10.1186/s42397-018-0015-9