Rapid Breeding Research Articles

Rapid colonisation, breeding and successful recruitment of eastern barn owls (

Abstract Context The introduced house mouse (Mus domesticus) causes significant economic damage to Australia’s agricultural enterprises. As part of the Marna Banggara Rewilding Project on the southern Yorke Peninsula (SYP), the present study focused on the eastern barn owl (Tyto alba delicatula) as a potential bio-controller of mice, by providing nesting spaces where natural hollows are limited. Aims To design an appropriate pole-mounted wooden nest box, and to enhance barn-owl-breeding and house-mouse-hunting capacity on farmland adjacent to remnant native vegetation. Methods A prototype nest box was collaboratively designed with a nest box manufacturer using data from previous barn owl studies and anecdotal reports. Eleven pole-mounted wooden boxes with platforms were installed at distances >1.4 km apart on properties near Warooka, southern Yorke Peninsula (SYP), and monitored over a 6-month period using external trail cameras. Key results Of the 11 nest boxes installed, 55 percent were colonised within a month after establishment, and 82 percent were colonised within 7 months. Occupied nest boxes were actively used by paired owls for mating, breeding and rearing of chicks, which resulted in up to 35 fledgling owlets. Conclusions The nest box design successfully supported eastern barn owl colonisation and reproduction on the SYP. The inclusion of the platform not only provided easy, minimally invasive monitoring of barn owl activity and prey intake by researchers, but also increased usable space for barn owl behaviours, such as copulation and wing flapping. Implications The important nest box design elements featured in this paper, such as the platform, high entrance hole, predator-proof pole and rear door access, can be implemented in barn owl conservation, research and on farms where alternative nesting sites are limited.

Genome-Wide Association Mapping and Genomic Prediction of Anther Extrusion in CIMMYT Hybrid Wheat Breeding Program via Modeling Pedigree, Genomic Relationship, and Interaction With the Environment.

Anther extrusion (AE) is the most important male floral trait for hybrid wheat seed production. AE is a complex quantitative trait that is difficult to phenotype reliably in field experiments not only due to high genotype-by-environment effects but also due to the short expression window in the field condition. In this study, we conducted a genome-wide association scan (GWAS) and explored the possibility of applying genomic prediction (GP) for AE in the CIMMYT hybrid wheat breeding program. An elite set of male lines (n = 603) were phenotype for anther count (AC) and anther visual score (VS) across three field experiments in 2017–2019 and genotyped with the 20K Infinitum is elect SNP array. GWAS produced five marker trait associations with small effects. For GP, the main effects of lines (L), environment (E), genomic (G) and pedigree relationships (A), and their interaction effects with environments were used to develop seven statistical models of incremental complexity. The base model used only L and E, whereas the most complex model included L, E, G, A, and G × E and A × E. These models were evaluated in three cross-validation scenarios (CV0, CV1, and CV2). In cross-validation CV0, data from two environments were used to predict an untested environment; in random cross-validation CV1, the test set was never evaluated in any environment; and in CV2, the genotypes in the test set were evaluated in only a subset of environments. The prediction accuracies ranged from −0.03 to 0.74 for AC and −0.01 to 0.54 for VS across different models and CV schemes. For both traits, the highest prediction accuracies with low variance were observed in CV2, and inclusion of the interaction effects increased prediction accuracy for AC only. In CV0, the prediction accuracy was 0.73 and 0.45 for AC and VS, respectively, indicating the high reliability of across environment prediction. Genomic prediction appears to be a very reliable tool for AE in hybrid wheat breeding. Moreover, high prediction accuracy in CV0 demonstrates the possibility of implementing genomic selection across breeding cycles in related germplasm, aiding the rapid breeding cycle.

Genome-wide association study uncovers genomic regions associated with grain iron, zinc and protein content in pearl millet

Pearl millet hybrids biofortified with iron (Fe) and zinc (Zn) promise to be part of a long-term strategy to combat micronutrient malnutrition in the arid and semi-arid tropical (SAT) regions of the world. Biofortification through molecular breeding is the way forward to achieving a rapid trait-based breeding strategy. This genome-wide association study (GWAS) was conducted to identify significant marker-trait associations (MTAs) for Fe, Zn, and protein content (PC) for enhanced biofortification breeding. A diverse panel of 281 advanced inbred lines was evaluated for Fe, Zn, and PC over two seasons. Phenotypic evaluation revealed high variability (Fe: 32–120 mg kg−1, Zn: 19–87 mg kg−1, PC: 8–16%), heritability (hbs2 ≥ 90%) and significantly positive correlation among Fe, Zn and PC (P = 0.01), implying concurrent improvement. Based on the Diversity Arrays Technology (DArT) seq assay, 58,719 highly informative SNPs were filtered for association mapping. Population structure analysis showed six major genetic groups (K = 6). A total of 78 MTAs were identified, of which 18 were associated with Fe, 43 with Zn, and 17 with PC. Four SNPs viz., Pgl04_64673688, Pgl05_135500493, Pgl05_144482656, and Pgl07_101483782 located on chromosomes Pgl04 (1), Pgl05 (2) and Pgl07 (1), respectively were co-segregated for Fe and Zn. Promising genes, ‘Late embryogenesis abundant protein’, ‘Myb domain’, ‘pentatricopeptide repeat’, and ‘iron ion binding’ coded by 8 SNPs were identified. The SNPs/genes identified in the present study presents prospects for genomics assisted biofortification breeding in pearl millet.

Introgression of the Afila Gene into Climbing Garden Pea (Pisum sativum L.)

The pea (Pisum sativum L.) is one of the most important crops in temperate agriculture around the world. In the tropics, highland production is also common with multiple harvests of nearly mature seeds from climbing plant types on trellises. While the leafless variant caused by the afila gene is widely used in developing row-cropped field peas in Europe, its use for trellised garden peas has not been reported. In this study we describe a pea breeding program for a high-elevation tropical environment in the Department of Nariño in Colombia, where over 16,000 hectares of the crop are produced. The most widespread climbing varieties in the region are ‘Andina’ and ‘Sindamanoy’, both of which have high-biomass architecture with abundant foliage. They are prone to many diseases, but preferred by farmers given their long production season. This plant type is expensive to trellis, with wooden posts and plastic strings used for vine staking constituting 52% of production costs. The afila trait could reduce these costs by creating interlocking plants as they do in field peas. Therefore, our goal for this research was to develop a rapid breeding method to introduce the recessive afila gene, which replaces leaves with tendrils, into the two commercial varieties used as recurrent parents (RPs) with three donor parents (DPs)—‘Dove’, ‘ILS3575′ and ‘ILS3568′—and to measure the effect on plant height (PH) and yield potential. Our hypothesis was that the afila gene would not cause linkage drag while obtaining a leafless climbing pea variety. Backcrossing was conducted without selfing for two generations and plants were selected to recover recurrent parent characteristics. Chi-square tests showed a ratio of 15 normal leaved to one afila leaved in the BC2F2 plants, and 31:1 in the BC3F2 generation. Selecting in the last of these generations permitted a discovery of tall climbing plants that were similar to those preferred commercially, but with the stable leafless afila. The method saved two seasons compared to the traditional method of progeny testing before each backcross cycle; the peas reached the BC2F2 generation in five seasons and the BC3F2 in seven seasons. This is advantageous with trellised peas that normally require half a year to reach maturity. Leafless garden peas containing the afila gene were of the same height as recurrent parents and, by the third backcross, were equally productive, without the high biomass found in the traditional donor varieties. The value of the afila gene and the direct backcrossing scheme is discussed in terms of garden pea improvement and crop breeding.

Development direction of molecular breeding of medicinal plants

To breed new varieties of medicinal plants with high resistance is the premise to ensure the production of high-quality medicinal materials. Molecular breeding using modern molecular biology and genetic technology can save time and effort and realize rapid and accurate breeding. Here we are trying to summarize the difference of breeding characteristics between medicinal plants and crops such as genetic background and breeding purpose. The strategy of molecular breeding of medicinal plants was summarized, and the four-phases breeding based on high-throughput sequencing and target gene mining was emphasized. We put forward the current molecular breeding of medicinal plants in the condition of four phases breeding is the optimal technological way of breeding, and gene editing breeding is the direction of medicinal plants breeding.

Molecular Sex Identification in the Hardy Rubber Tree (Eucommia ulmoides Oliver) via ddRAD Markers.

Eucommia ulmoides, also known as the industrially and medicinally important hardy rubber tree, is the sole species of Eucommiaceae. Nevertheless, its dioecious property hinders sex recognition by traditional morphological observation at very early developmental stages, thus inhibiting breeding and economic cropping. In this study, double-digest restriction site-associated DNA sequencing (ddRAD-seq) was applied to screen sex-linked molecular markers for sex identification and investigation of the sex determination system in 20 male and female E. ulmoides individual plants, respectively. In consequence, five candidate male-specific loci but no female-specific loci were predicated among the 183,752 male and 147,122 female catalogue loci by bioinformatics analysis. Subsequent PCR (polymerase chain reaction) amplification and Sanger sequencing examinations were performed on another 24 individuals, 12 for each sex, from a separate population. One ideal sex-linked locus, MSL4, was identified among the five putative male-specific loci that were found using ddRAD data. MSL4 is 479 bp in length and highly conserved in all the male individuals, suggesting its feature of being stable and repeatable. Our results also indicated that the sex of E. ulmoides is likely determined genetically. In short, this study provides a consistent and reproducible ddRAD marker (MSL4) that is able to discriminate male from female seedlings in E. ulmoides, which will be valuable for rapid breeding practice and better commercial production of this economically important tree.

Speed breeding short-day crops by LED-controlled light schemes

Key messageA simple and rapid speed breeding system was developed for short-day crops that enables up to five generations per year using LED lighting systems that allow very specific adjustments regarding light intensity and quality.Plant breeding is a key element for future agricultural production that needs to cope with a growing human population and climate change. However, the process of developing suitable cultivars is time-consuming, not least because of the long generation times of crops. Recently, speed breeding has been introduced for long-day crops, but a similar protocol for short-day crops is lacking to date. In this study, we present a speed breeding protocol based on light-emitting diodes (LEDs) that allow to modify light quality, and exemplarily demonstrate its effectiveness for the short-day crops soybean (Glycine max), rice (Oryza sativa) and amaranth (Amaranthus spp.). Adjusting the photoperiod to 10 h and using a blue-light enriched, far-red-deprived light spectrum facilitated the growth of short and sturdy soybean plants that flowered ~ 23 days after sowing and matured within 77 days, thus allowing up to five generations per year. In rice and amaranth, flowering was achieved ~ 60 and ~ 35 days after sowing, respectively. Interestingly, the use of far-red light advanced flowering by 10 and 20 days in some amaranth and rice genotypes, respectively, but had no impact on flowering in soybeans, highlighting the importance of light quality for speed breeding protocols. Taken together, our short-day crops’ speed breeding protocol enables several generations per year using crop-specific LED-based lighting regimes, without the need of tissue culture tools such as embryo rescue. Moreover, this approach can be readily applied to a multi-storey 96-cell tray-based system to integrate speed breeding with genomics, toward a higher improvement rate in breeding.

Comparative Transcriptome Analysis of Gene Expression and Regulatory Characteristics Associated with Different Vernalization Periods in Brassica rapa.

Brassica rapa is an important Chinese vegetable crop that is beneficial to human health. The primary factor affecting B. rapa yield is low temperature, which promotes bolting and flowering, thereby lowering its commercial value. However, quickened bolting and flowering can be used for rapid breeding. Therefore, studying the underlying molecular mechanism of vernalization in B. rapa is crucial for solving production-related problems. Here, the transcriptome of two B. rapa accessions were comprehensively analyzed during different vernalization periods. During vernalization, a total of 974,584,022 clean reads and 291.28 Gb of clean data were obtained. Compared to the reference genome of B. rapa, 44,799 known genes and 2280 new genes were identified. A self-organizing feature map analysis of 21,035 differentially expressed genes was screened in two B. rapa accessions, ‘Jin Wawa’ and ‘Xiao Baojian’. The analysis indicated that transcripts related to the plant hormone signal transduction, starch and sucrose metabolism, photoperiod and circadian clock, and vernalization pathways changed notably at different vernalization periods. Moreover, different expression patterns of TPS, UGP, CDF, VIN1, and seven hormone pathway genes were observed during vernalization between the two accessions. The transcriptome results of this study provide a new perspective on the changes that occur during B. rapa vernalization, as well as serve as an excellent reference for B. rapa breeding.

In-Frame and Frame-Shift Editing of the Ehd1 Gene to Develop Japonica Rice With Prolonged Basic Vegetative Growth Periods.

Japonica rice has become increasingly popular in China owing to its superior grain quality. Over the past decades, “indica to japonica” projects have been proposed to promote cultivation of japonica rice in low latitudes in China. Traditionally, japonica varieties were planted mainly in mid latitudes in the northeast plain and Yangtze River region. The key obstacle for introducing elite mid-latitude japonica varieties to low latitudes is the severe shortening of growth period of the japonica varieties due to their sensitivity to low-latitude short photoperiod and high temperature. Here we report development of new japonica rice with prolonged basic vegetative growth (BVG) periods for low latitudes by targeted editing the Early heading date 1 (Ehd1) gene. Using CRISPR/Cas9 system, we generated both frame-shift and/or in-frame deletion mutants in four japonica varieties, Nipponbare, Longdao16, Longdao24, and Xiushui134. When planting at low-latitude stations, the frame-shift homozygous lines exhibited significantly longer BVG periods compared with wild-types. Interestingly, we observed that minor deletion of the first few residues within the receiver domain could quantitatively impair the function of Ehd1 on activation of Hd3a and RFT1, resulting in an intermediate-long BVG period phenotype in the homozygous in-frame deletion ehd1 lines. Field investigation further showed that, both the in-frame and frame-shift lines exhibited significantly improved yield potential compared with wild-types. Our study demonstrates an effective approach to rapid breeding of elite japonica varieties with intermediate-long and long BVG periods for flexible cropping systems in diverse areas or under different seasons in southern China, and other low-latitude regions.

Thorium Utilization in Pressurized Water Reactors Using Bimetallic Thorium-Zirconium Alloy Cladding

A fuel rod design consisting of a bimetallic cladding tube of thorium metal bonded to a zirconium alloy and containing seed fuel in the interior space is proposed for thorium utilization in pressurized water reactors. The design mitigates the severe thermal penalty that arises in radial microheterogeneous designs when thorium is present as an oxide. The level of thorium loading has an important effect on the achievable discharge exposure as too high a loading results in a large reactivity penalty that is not compensated by rapid enough 233U breeding. In the bimetallic cladding design, the level of thorium loading could be adjusted by varying the thorium metal thickness, and analyses are presented to evaluate optimal levels of thorium loading. Results of cases for higher levels of initial seed loading are presented with a view to extending exposure and reducing the number of discharged assemblies. Liquid metal bonding the seed fuel–cladding gap is preferable as it reduces the seed fuel temperature and at the same time provides more room for fuel swelling. Helium bonding the gap is also possible with a seed fuel modified by an inert matrix. Both approaches need data for fuel thermal modeling, swelling, and fission gas release at high burnup not currently available.

Introgressing blue mold resistance into elite apple germplasm by rapid cycle breeding and foreground and background DNA-informed selection

Apple blue mold causes significant postharvest economic losses worldwide. A blue mold resistance locus, qM-Pe3.1, was previously identified on chromosome 3 of Malus sieversii PI 613981, a wild accession with inferior fruit quality. Introgression of the resistance allele into elite breeding germplasm is difficult and success of introgression and the effect of the PI 613981 genome on fruit quality cannot be phenotypically evaluated until fruiting, which occurs approximately 5 years from seed. In this study, introgression of the qM-Pe3.1 resistance allele was achieved by rapid cycle breeding, utilizing the transgenic line T1190 constitutively expressing the BpMADS4 early-flowering gene. This was supported by DNA-based diagnostic information that enabled marker-assisted selection for blue mold resistance using a locus-specific DNA test developed to detect the qM-Pe3.1 resistance allele in offspring (foreground selection). Of 75 second-generation ([‘Gala’ × PI 613981] × T1190) offspring carrying BpMADS4, 43 also carried the qM-Pe3.1 resistance allele. DNA tests for other trait loci were used to identify other desirable alleles related to fruit quality in progeny and 6874 genome-wide SNP markers (from an apple 20K Illumina® SNP array) were used to identify undesirable genomic segments of PI 613981 (background selection). Three individuals identified with favorable recombination close to qM-Pe3.1 and less than 25% of M. sieversii unimproved genome were selected as best suited for the elimination of unimproved DNA segments in subsequent generations. Our pipeline for introgression of qM-Pe3.1, facilitated by marker-assisted foreground and background selection, successfully advanced this promising germplasm in readiness for the next generation.

Determination of Color and Heat Level of Some Resistance Sources and Improved Pepper Genotypes

Background: In this study, the capsaicin content, heat level and color of nine pepper genotypes and varieties belonging to Capsicum annuum and Capsicum chinense were described at different ripening stages. Heat level and color is a desirable feature for Turkish pepper consumers. Therefore, knowledge on the heat level and of Turkish pepper genotypes is important for a future breeding project aiming variety development. Methods: Turkish materials (Alata 10, 15 and 111) were improved from the pepper collection of Alata Horticultural Research Institute-Turkey. The Rwandan variety Pili-Pili is consumed in Rwandan cuisine. The capsaicin content of the Alata collection and Pili-Pili were identified both at immature and red ripening stages. In addition, some accessions carrying various resistances to diseases were evaluated: namely Er-Fu-Tou (Cucumber Mosaic Virus), C29 (Phytophthora capsici and Potato Virus Y), PI 260429 (Tobacco Mosaic Virus) and PI 152225 (Tomato spotted wilt virus); for these accessions, sampling was done at red ripening stage. High-performance liquid chromatography (HPLC) was used for identifying capsaicinoids and extraction was performed by sodium acetate saturated ethanol. ASTA 20.0 method was applied to measure the extractable color of improved lines. Results: •Results demonstrated that there was considerable variation among genotypes. •The highest capsaicin content and heat level were detected in the genotype PI 152225. For dihydrocapsaicin content, Er-Fu-Tou variety was the first and followed by PI 260429 and PI 152225. •Heat level in pepper involves the relationship between capsaicin and dihydrocapsaicin and therefore, it is important to convert to the Scoville Heat Unit (SHU). The most pungent genotype PI 152225 was followed by Pili-Pili variety (red stage), Er-Fu-Tou, Rwandan Pili-Pili variety (immature stage), Alata 111 (red stage) and PI 260429. •The highest ASTA value was detected in mature fruits of Er-Fu-Tou genotype with 217 ASTA color value and it was followed by improved line Alata 111 from Kahramanmaras pepper population with 173 ASTA. Conclusions: At the end of study, Er-Fu-Tou (CMV resistant) and PI 152225 (TSWV resistant) lines were found to be useful to improve varieties having both quality properties and resistance to diseases from the Kahramanmaras red pepper population via short term breeding program while they were not suitable to improve sweet pepper with rapid breeding program. Rwandan variety Pili-Pili was not found appropriate to improve varieties producing high quality dried pepper.

Rapid plastic breeding response to rain matches peak prey abundance in a tropical savanna bird.

Changes in climate are shifting the timing of life cycle events in the natural world. Compared to northern temperate areas, these effects are relatively poorly understood in tropical and southern regions, where there is limited information on how timing of breeding and food availability are affected by climatic factors, and where patterns of breeding activity are more unpredictable within and between years. Combining a new statistical modelling approach with 5years of continuous individual-based monitoring of a monsoonal tropical insectivorous bird, we quantified (a) the proximate climatic drivers at two trophic levels: timing of breeding and abundance of arthropod prey; (b) the effect of climate variation on reproductive output and (c) the role of individual plasticity. Rainfall was identified as the main determinant of phenology at both trophic levels. Throughout the year, likelihood of egg laying increased very rapidly in response to even small amounts of rain during the preceding 0-3weeks. Adult body mass and male sperm storage also increased rapidly after rain, suggesting high breeding preparedness. Additionally, females were flexible, since they were more likely to nest whether their previous attempt was longer ago and unsuccessful. Arthropod abundance also increased after rainfall, but more slowly, with a peak around 10weeks. Therefore, the peak food availability coincided with the presence of dependent fledglings. Fitness benefits of nesting after more rain appeared to be linked to offspring quantity rather than quality: nest attempts following higher rainfall produced larger clutches, but showed no improvement in nestling mass or relative fledging success. The response of clutch size to rainfall was plastic, since repeated sampling showed that individual females laid larger clutches after more rain, possibly mediated by improved body mass. Rapid, individually flexible breeding in response to rainfall and slower increase in arthropod abundance also as a response to rainfall, might buffer insectivorous species living in tropical seasonal environments from climate change-induced phenological trophic mismatches.

A selection method of chickens with blue-eggshell and dwarf traits by molecular marker-assisted selection

The blue-eggshell and dwarf traits have an important economic value in poultry production. Using a genetic aggregation-based strategy, the molecular marker-assisted selection technology was jointly used to provide a rapid breeding method for pure strain chickens simultaneously with hens exhibiting the blue-eggshell and dwarf traits. Overall, 80 male dwarf chickens and 1,000 hybrid blue-eggshell hens (F0) were used for the hybridization experiment. Subsequently, the crossing of F1 or F2 chicks was performed in succession. The F1 and F2 chicks were respectively detected by the joint molecular markers of the solute carrier organic anion transporter family, namely, 1B3 (SLCO1B3) and the growth hormone receptor (GHR) genes, which relate to blue-eggshell and dwarf traits. Meanwhile, the selection of blue-eggshell and dwarf phenotypes was used to validate the data obtained by the molecular markers. The results showed that F1 chicks included the heterozygous and wild-type of SLCO1B3, as well as the homozygous (hens) and heterozygous (roosters) of GHR. However, F2 chicks included 3 different genotypes of both SLCO1B3 and GHR. Ultimately, 196 F1 roosters (concurrently with heterozygous genotype of SLCO1B3 and GHR) and 1,073 F1 hens (concurrently with heterozygous genotype of SLCO1B3 and homozygous genotype of GHR) were obtained from the initial 10,040 F1 chicks. Further, 27 F2 roosters and 345 F2 hens, which simultaneously carried the homozygous genotype of SLCO1B3 and GHR, were screened from the initial 6,000 F2 chicks. Data obtained on the blue-eggshell and dwarf phenotypes were consistent with the results by molecular markers. Similarly, the purity verification of the strain obtained through 2 crossing experiments (F0♂ × F2♀ and F2♂ × F2♀) revealed that all chickens had the blue-eggshell and dwarf traits, supporting that the obtained F2 strain was pure. In summary, for the first time, we successfully bred a pure strain chicken with blue-eggshell and dwarf traits by jointly using the molecular markers of the SLCO1B3 and GHR genes. Our study provides a new method for the rapid cultivation of new chicken strains.

Predicting the quality of ryegrass using hyperspectral imaging

BackgroundThe quality of forage plants is a crucial component of animal performance and a limiting factor in pasture based production systems. Key forage attributes that may require improvement include the sugar, lipid, protein and energy contents of the vegetative parts of these plants. The aim of this study was to evaluate the potential capacity of hyperspectral imaging (HSI) for non-invasive assessment of forage chemical composition. Hyperspectral image data within the visible near-infrared range into the extended near-infrared covering 550–1700 nm wavelengths were obtained from 185 accessions of ryegrass (Lolium perenne), which were also analysed for 13 forage quality attributes.ResultsMedium to high predictive power was observed for the HSI models of total sugars (R2 validation of 0.58), high molecular weight sugars (R2 validation of 0.63), %Ash (R2 validation of 0.50) and %Nitrogen (R2 validation of 0.70). Significant HSI models with low R2 validation of 0.1–0.5 were also obtained for low molecular weight sugars, NDF (%), ADF (%), DOMD (% DM), ME (MJ/kg DM), DM (%), Ca (mg/g) and OM (%). We also observed significant differences in the chemical composition between the pseudostems and leaves of the plants for each accession. The power of HSI for prediction of these differences within plants was also demonstrated.ConclusionThis study paves the way for the HSI technology to be used for in-field estimation of forage composition attributes in perennial ryegrass. This will allow more rapid genetic-based selection and breeding for a trait that is normally expensive to measure providing a cheaper, non-destructive and high throughput screening tool.

Determination of genetic effects of SERPINA3 on important growth traits in beef cattle

Serine protease inhibitor protein 3 (serpin peptidase inhibitor, clade A, member 3, SERPINA3) is a member of the serpin superfamily, probably related to the yield and quality of muscle. This study focuses on the relationship between SERPINA3 gene polymorphism and growth traits in beef cattle. The study first uses sequencing pooled DNA samples (Pool-Seq), PCR-RFLP and Tetra-primer ARMS-PCR techniques to determine the genetic polymorphisms of SERPINA3 in 765 beef cattle. Then, the polymorphic loci were correlated with the growth characters of cattle. Five SNPs (SNP1:A-648G, SNP2:T6496A, SNP3:G2495A, SNP4:T2595A, SNP5:A2615G) were found, located in the promoter, introns 5 and SNP 3, 4, 5 were in exons 2, respectively. The observed He was from 0.44 to 0.5, Ne were approaching 2 (1.78 to 2.00). The maximum and minimum PIC (polymorphism information content) values were 0.37 and 0.34, respectively. The association analysis results showed that the SNPs had a significant height in the chest girth and body length. (p < 0.05 or p < 0.01). This will provide important information for the rapid breeding of Chinese yellow cattle and the establishment of a molecular genetic marker database.

Targeted deletion of rice retrotransposon Tos17 via CRISPR/Cas9.

A successful example of transposon deletion via CRISPR/Cas9-mediated genome editing suggests a novel alternative approach to plant breeding. Transposition of transposable elements (TEs) can affect adjacent genes, leading to changes in genetic traits. Expression levels and patterns, splicing and epigenetic status, and function of genes located in, or near, the inserted/excised locus can be affected. Artificial modification of loci adjacent to TEs, or TEs themselves, by genome editing could mimic the translocation of TEs that occurs in nature, suggesting that it might be possible to produce novel plants by modification of TEs via genome editing. To our knowledge, there are no reports thus far of modification of TEs by genome editing in plants. In this study, we performed targeted deletion of the Tos17 retrotransposon, which is flanked at both ends by long terminal repeat (LTR) sequences, via genome editing in rice. We succeeded in targeted mutagenesis of the LTR, and targeted deletion between LTRs, in calli transformed with CRISPR/Cas9 vectors for the Tos17 LTR. Moreover, we also successfully obtained regenerated plants derived from transformed calli and plants homozygous for lacking Tos17 in the next generation. Taken together, our results demonstrate successful deletion of the Tos17 retrotransposon from the rice genome by targeted mutagenesis using CRISPR/Cas9. We believe that this strategy could be applied to other TEs in many plant species, providing a rapid breeding technology as an alternative means to re-activate expression of agronomically important genes that have been inactivated by TE insertion, especially in plants such as fruit trees, in which it is difficult to maintain parental agronomical traits by cross-breeding due to high heterozygosity.

EFEKTIFITAS LARVASIDA AKAR BIDURI (CALOTROPIS GIGANTEA) SEBAGAI ALTERNATIF PEMBASMI JENTIK NYAMUK AEDES AEGYPTI

Biduri plants (Calatropis gigantea) is a wild plant that is very difficult to destroybecause of rapid breeding. One of the toxins contained in Biduri is saponin. Therefore Biduriplants very well be used as a repellent for Aedes aegypti mosquito larvae. The researchobjective was to determine the effectiveness of the roots Biduri larvicides against Aedesaegypti larvae mortality.This research is True Experiments with posttest study design OnlyControl Group Design. Statistical test results obtained by the one way Anova sig. = 0.000 sothat ρ &lt;α (0.05) means that there is a significant influence on differences in dosing solutionBiduri roots are used against Aedes aegypti larvae mortality. Further post hoc test to determinedifferences in average - average each treatment group using Multiple Comparisons Analysis,LSD (Least Square Difference) obtained sig. = 0.00 so that ρ &lt;α (0.05) means that there aresignificant differences in the deadly Aedes aegypti larvae of the four doses were given.Control of Aedes aegypti larvae using Biduri root solution can be done by affixing the rootsolution with 38 ml of solution Biduri root Biduri every 1 liter of water for 24 hours ofexposure.

Environmental watering triggers rapid frog breeding in temporary wetlands within a regulated river system

The Murray–Darling basin is the most extensively regulated river system in Australia and delivery of environmental water is increasingly being used in its management. Due to their sensitivity to hydrological changes, frogs are often targets of environmental watering actions, and site-specific data on their habitat and water requirements are essential for achieving optimal ecological outcomes. I investigated the spatial and temporal response of frogs to the environmental watering of temporary wetlands in the lower River Murray region to determine if watering (timing, duration and quality) triggered a breeding response and provided opportunities for juvenile recruitment. Frog and tadpole surveys were conducted each month from December 2014 to April 2015 at watered temporary wetlands and permanent wetlands along on the River Murray in South Australia. All seven frog species known from the lower Murray valley bred opportunistically after deliberate flooding of temporary wetland sites. Breeding was immediate and was observed at all watered sites. Tadpole development was largely synchronous and rapid, with the majority of frogs metamorphosing 3 to 4 months after wetlands were inundated. The abundance and diversity of tadpoles and frogs was significantly greater in watered wetlands than in permanent wetlands. Wetlands required inundation for a minimum duration of 4 months over summer and autumn to allow sufficient time for tadpoles to complete development. Environmental watering of wetlands via pumping, whilst highly localised, can target key ecological assets in dry conditions, and may provide critical breeding opportunities and refugia for maintaining frog species and their ecological roles.

Accelerating Soybean Breeding in a CO2-Supplemented Growth Chamber.

Soybean (Glycine max) is the most important dicot crop worldwide, and is increasingly used as a model legume due to the wide availability of genomic soybean resources; however, the slow generation times of soybean plants are currently a major hindrance to research. Here, we demonstrate a method for accelerating soybean breeding in compact growth chambers, which greatly shortens the generation time of the plants and accelerates breeding and research projects. Our breeding method utilizes commonly used fluorescent lamps (220 �mol m–2 s–1 at the canopy level), a 14 h light (30�C)/10 h dark (25�C) cycle and carbon dioxide (CO2) supplementation at >400 p.p.m. Using this approach, the generation time of the best-characterized elite Japanese soybean cultivar, Enrei, was shortened from 102–132 d reported in the field to just 70 d, thereby allowing up to 5 generations per year instead of the 1–2 generations currently possible in the field and/or greenhouse. The method also facilitates the highly efficient and controlled crossing of soybean plants. Our method uses CO2 supplementation to promote the growth and yield of plants, appropriate light and temperature conditions to reduce the days to flowering, and the reaping and sowing of immature seeds to shorten the reproductive period greatly. Thus, the appropriate parameters enable acceleration of soybean breeding in the compact growth chambers commonly used for laboratory research. The parameters used in our method could therefore be optimized for other species, cultivars, accessions and experimental designs to facilitate rapid breeding in a wide range of crops.