Breeding maize under biodynamic-organic conditions for nutritional value and N efficiency/N2 fixation

AbstractAn overview is given for an ongoing maize breeding program that improves populations, inbreds, and hybrids in the Midwestern USA. Breeding and selection occurred under biodynamic conditions in Wisconsin, on an organic winter nursery in Puerto Rico, a biodynamic winter nursery in Hawaii, and a conventional winter nursery in Chile. Emphasis is on improving protein quality, carotenoid content, competitiveness with weeds, nitrogen (N) efficiency/N2 fixation, and cross incompatibility to pollen from genetically engineered (GE) maize. Philosophy is that the plant species is a responding partner in the breeding process. Adaptation and selection emphasizes vigor and yield under N limited conditions. The Ga1 and Tcb1 alleles were utilized to induce cross incompatibility. The program resulted in inbreds and hybrids with increased N efficiency and protein quality coupled with softer grain texture, more chlorophyll in foliage, and densely branched root growth in the topsoil relative to conventionally bred cultivars under N limited conditions. Grain protein quality was improved by utilizing opaque kernels that emerged in populations during the course of the program in surprisingly high frequencies. N efficiency was accentuated by breeding with landraces that may fix N2 with microbes coupled with selection for response traits under N-limited conditions. When grown next to conventional hybrids, the best hybrids from this program have exhibited 30% more methionine and 16% more protein in grain and more protein/ha.

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Improvement of effectiveness in maize breeding

Acta Agronomica Hungarica ◽

10.1556/aagr.54.2006.3.10 ◽

2006 ◽

Vol 54 (3) ◽

pp. 351-358 ◽

Cited By ~ 2

Author(s):

P. Pepó

Keyword(s):

Recurrent Selection ◽

Genetic Manipulation ◽

Field Testing ◽

Tissue Cultures ◽

Maize Breeding ◽

Breeding Programmes ◽

Speed Up ◽

Selection For

Plant regeneration via tissue culture is becoming increasingly more common in monocots such as maize (Zea mays L.). Pollen (gametophytic) selection for resistance to aflatoxin in maize can greatly facilitate recurrent selection and the screening of germplasm for resistance at much less cost and in a shorter time than field testing. In vivo and in vitro techniques have been integrated in maize breeding programmes to obtain desirable agronomic attributes, enhance the genes responsible for them and speed up the breeding process. The efficiency of anther and tissue cultures in maize and wheat has reached the stage where they can be used in breeding programmes to some extent and many new cultivars produced by genetic manipulation have now reached the market.

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Hybrid maize breeding with doubled haploids. IV. Number versus size of crosses and importance of parental selection in two-stage selection for testcross performance

Theoretical and Applied Genetics ◽

10.1007/s00122-008-0770-y ◽

2008 ◽

Vol 117 (2) ◽

pp. 251-260 ◽

Cited By ~ 13

Author(s):

Thilo Wegenast ◽

C. Friedrich H. Longin ◽

H. Friedrich Utz ◽

Albrecht E. Melchinger ◽

Hans Peter Maurer ◽

...

Keyword(s):

Doubled Haploids ◽

Maize Breeding ◽

Two Stage ◽

Parental Selection ◽

Testcross Performance ◽

Selection For ◽

Hybrid Maize

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Genetic dissection of yield-related traits and mid-parent heterosis for those traits in maize (Zea mays L.)

BMC Plant Biology ◽

10.1186/s12870-019-2009-2 ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 4

Author(s):

Qiang Yi ◽

Yinghong Liu ◽

Xianbin Hou ◽

Xiangge Zhang ◽

Hui Li ◽

...

Keyword(s):

Genetic Basis ◽

Recombinant Inbred Lines ◽

Kernel Weight ◽

Genetic Dissection ◽

Hybrid Mapping ◽

Maize Breeding ◽

Phenotypic Variations ◽

Selection For ◽

Genomic Regions ◽

Mapping Populations

Abstract Background Utilization of heterosis in maize could be critical in maize breeding for boosting grain yield. However, the genetic architecture of heterosis is not fully understood. To dissect the genetic basis of yield-related traits and heterosis in maize, 301 recombinant inbred lines derived from 08 to 641 × YE478 and 298 hybrids from the immortalized F2 (IF2) population were used to map quantitative trait loci (QTLs) for nine yield-related traits and mid-parent heterosis. Results We observed 156 QTLs, 28 pairs of loci with epistatic interaction, and 10 significant QTL × environment interactions in the inbred and hybrid mapping populations. The high heterosis in F1 and IF2 populations for kernel weight per ear (KWPE), ear weight per ear (EWPE), and kernel number per row (KNPR) matched the high percentages of QTLs (over 50%) for those traits exhibiting overdominance, whereas a notable predominance of loci with dominance effects (more than 70%) was observed for traits that show low heterosis such as cob weight per ear (CWPE), rate of kernel production (RKP), ear length (EL), ear diameter (ED), cob diameter, and row number (RN). The environmentally stable QTL qRKP3–2 was identified across two mapping populations, while qKWPE9, affecting the trait mean and the mid-parent heterosis (MPH) level, explained over 18% of phenotypic variations. Nine QTLs, qEWPE9–1, qEWPE10–1, qCWPE6, qEL8, qED2–2, qRN10–1, qKWPE9, qKWPE10–1, and qRKP4–3, accounted for over 10% of phenotypic variation. In addition, QTL mapping identified 95 QTLs that were gathered together and integrated into 33 QTL clusters on 10 chromosomes. Conclusions The results revealed that (1) the inheritance of yield-related traits and MPH in the heterotic pattern improved Reid (PA) × Tem-tropic I (PB) is trait-dependent; (2) a large proportion of loci showed dominance effects, whereas overdominance also contributed to MPH for KNPR, EWPE, and KWPE; (3) marker-assisted selection for markers at genomic regions 1.09–1.11, 2.04, 3.08–3.09, and 10.04–10.05 contributed to hybrid performance per se and heterosis and were repeatedly reported in previous studies using different heterotic patterns is recommended.

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Regulators of Epithelial Sodium Channels in Aldosterone-Sensitive Distal Nephrons (ASDN): Critical Roles of Nedd4L/Nedd4-2 and Salt-Sensitive Hypertension

International Journal of Molecular Sciences ◽

10.3390/ijms21113871 ◽

2020 ◽

Vol 21 (11) ◽

pp. 3871

Author(s):

Tomoaki Ishigami ◽

Tabito Kino ◽

Shintaro Minegishi ◽

Naomi Araki ◽

Masanari Umemura ◽

...

Keyword(s):

Ubiquitin Ligase ◽

Protein Quality ◽

E3 Ubiquitin Ligase ◽

Genetically Engineered ◽

Post Translational Modification ◽

Mice Model ◽

Vascular Medicine ◽

Cell Cycle Protein ◽

Genetically Engineered Mice ◽

Salt Sensitive Hypertension

Ubiquitination is a representative, reversible biological process of the post-translational modification of various proteins with multiple catalytic reaction sequences, including ubiquitin itself, in addition to E1 ubiquitin activating enzymes, E2 ubiquitin conjugating enzymes, E3 ubiquitin ligase, deubiquitinating enzymes, and proteasome degradation. The ubiquitin–proteasome system is known to play a pivotal role in various molecular life phenomena, including the cell cycle, protein quality, and cell surface expressions of ion-transporters. As such, the failure of this system can lead to cancer, neurodegenerative diseases, cardiovascular diseases, and hypertension. This review article discusses Nedd4-2/NEDD4L, an E3-ubiquitin ligase involved in salt-sensitive hypertension, drawing from detailed genetic dissection analysis and the development of genetically engineered mice model. Based on our analyses, targeting therapeutic regulations of ubiquitination in the fields of cardio-vascular medicine might be a promising strategy in future. Although the clinical applications of this strategy are limited, compared to those of kinase systems, many compounds with a high pharmacological activity were identified at the basic research level. Therefore, future development could be expected.

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Plasmid carriage can limit bacteria–phage coevolution

Biology Letters ◽

10.1098/rsbl.2015.0361 ◽

2015 ◽

Vol 11 (8) ◽

pp. 20150361 ◽

Cited By ~ 9

Author(s):

Ellie Harrison ◽

Julie Truman ◽

Rosanna Wright ◽

Andrew J. Spiers ◽

Steve Paterson ◽

...

Keyword(s):

Conjugative Plasmid ◽

Phage Resistance ◽

Resistance Mutations ◽

Accessory Gene ◽

Bacterial Populations ◽

High Frequencies ◽

Qualitative Resistance ◽

Selection For ◽

Evolutionary Consequences ◽

Plasmid Carriage

Coevolution with bacteriophages is a major selective force shaping bacterial populations and communities. A variety of both environmental and genetic factors has been shown to influence the mode and tempo of bacteria–phage coevolution. Here, we test the effects that carriage of a large conjugative plasmid, pQBR103, had on antagonistic coevolution between the bacterium Pseudomonas fluorescens and its phage, SBW25 ϕ 2. Plasmid carriage limited bacteria–phage coevolution; bacteria evolved lower phage-resistance and phages evolved lower infectivity in plasmid-carrying compared with plasmid-free populations. These differences were not explained by effects of plasmid carriage on the costs of phage resistance mutations. Surprisingly, in the presence of phages, plasmid carriage resulted in the evolution of high frequencies of mucoid bacterial colonies. Mucoidy can provide weak partial resistance against SBW25 ϕ 2, which may have limited selection for qualitative resistance mutations in our experiments. Taken together, our results suggest that plasmids can have evolutionary consequences for bacteria that go beyond the direct phenotypic effects of their accessory gene cargo.

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Recurrent selection method for improvement of lutein and zeaxanthin in orange waxy corn populations

Australian Journal of Crop Science ◽

10.21475/ajcs.19.13.04.p1507 ◽

2019 ◽

Vol 13 ((04) 2019) ◽

pp. 566-573 ◽

Cited By ~ 1

Author(s):

Watanyoo Khamkoh ◽

Danupol Ketthaisong ◽

Khomsorn Lomthaisong ◽

Kamol Lertrat ◽

Bhalang Suriharn

Keyword(s):

Recurrent Selection ◽

Total Yield ◽

Selection Criterion ◽

Carotenoid Content ◽

Total Carotenoid ◽

Color Parameter ◽

Total Carotenoid Content ◽

Selection For ◽

Waxy Corn ◽

Β Carotene

The information on the responses to simple recurrent selection for yield and total carotenoid content in orange waxy corn is lacking. The objectives were to evaluate the responses to simple recurrent selection for two cycles for yield and carotenoids of orange waxy corn population and to investigate the correlations between color parameter with carotenoids in waxy corn kernels. Parental sources of germplasm with differences in kernel colors and levels of disease resistance were used for generation of a base population of orange waxy corn. A simple recurrent selection for superior phenotypes was practiced on this population for two selection cycles. Cycle 0 (C0), C1 and C2 were evaluated for two locations in 2016. The cycles showed significant differences for most traits except for plant height. The locations contributed to large portions of total variation in total yield, whereas selection cycle contributed to large portions of total variations in lutein, zeaxanthin, β-carotene and total carotenoid content and color parameter (ho), indicating that selection for carotenoids would be possible. Simple recurrent selection for two cycles increased total yield and husked ear weight of 23.2% and 15.0%, respectively. Simple recurrent selection for two cycles also increased lutein, zeaxanthin, β-carotene and total carotenoid content with increasing percentages ranging from 18.5 to 196.6%. The results indicated that population improvement by simple recurrent selection could be useful in increasing these traits. Color parameter at immature stage and dry stage was negatively and significantly correlated with lutein, zeaxanthin, β-carotene and total carotenoid content, indicating that color parameter can be used as an indirect selection criterion for these traits.

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