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Source-sink relationships in wheat and the role of N: Source and sink interactions and balance, and applications in breeding
No full text34 slide
Optimizing genomic parental selection for categorical and continuous-categorical multi-trait mixtures
No full textThis study presents a novel approach for the optimization of genomic parental selection in breeding programs involving categorical and continuous-categorical multi-trait mixtures (CMs and CCMMs). Utilizing the Bayesian decision theory (BDT) and latent trait models within a multivariate normal distribution framework, we address the complexities of selecting new parental lines across ordinal and continuous traits for breeding. Our methodology enhances precision and flexibility in genetic selection, validated through extensive simulations. This unified approach presents significant potential for the advancement of genetic improvements in diverse breeding contexts, underscoring the importance of integrating both categorical and continuous traits in genomic selection frameworks
Adaptation and grain yield stability analysis of winter wheat cultivars with and without fungicides treatment from national variety trials in Sweden
No full textThe multi-environment evaluation of wheat genotypes for grain yield is an integral part of germplasm enhancement since it plays a pivotal role in sustainable production. A total of 178 winter wheat cultivars were evaluated across 20 environments in Sweden from 2016 to 2020, with 52 to 59 cultivars tested per year as part of the Swedish National Trials (Sverigeförsöken). The genotypes were evaluated for grain yield performance with and without fungicide treatments. Additive main-effects and multiplicative interaction (AMMI) and genotype plus genotype-by-environment interaction (GGE) biplot methods were explored to estimate the genotype-by-environment interaction (GEI) for grain yield performance. ANOVA revealed a significant variation between treatments, genotypes in all years, and GEI in all years except 2018. The majority of the explained variance came from the environment, with a range of 61-88% across the five-year trial. The 20 sites were grouped into two to four mega-environments in the yearly studies. From the fungicide-treated trials, G 0512LT3, Informer, SG SU1563-15, LG Imposanto, and Pondus were identified as the most stable and high-yielding cultivars each year. From the fungicide-untreated trials, Informer, Ancher Greece, RGT Saki, and Pondus were the best-performing cultivars and could be good candidates for organic wheat cultivation
Implementing conjunctive management of water resources for sustainable and inclusive irrigation Development in Western Nepal
No full text8 slide
Heterodera schachtii (Nematoda: Heteroderidae) associated with cabbage-cultivation systems in anatolia region of Türkiye
No full textHeterodera schachtii (Schmidt, 1871) (Nematoda: Heteroderidae) is one of the most widespread plant-parasitic nematodes (PPNs) associated with cabbages, which cause severe yield losses in cruciferous vegetables. This study aimed to improve the current understanding of the prevalence and detection of H. schachtii in the cabbage-growing areas of Ni & gbreve;de Province, T & uuml;rkiye. Field surveys were conducted between November and December 2021, and 100 soil samples were collected immediately after cabbage harvesting. Heterodera schachtii populations were identified by morphological and morphometric methods along with Internal Transcribed Spacer of the ribosomal region (ITS-rDNA) and Cytochrome Oxidase Subunit (COI-mtDNA) sequencing. The mean body length of H. schachtii was 463 +/- 7 mu m, while stylet and hyaline length ranged between 20.7-27.8 mu m and 20.1-32.1 mu m, respectively. Nearly half of the surveyed areas were infested with H. schachtii with a 41% incidence rate. However, the Merkez District had the highest proportion of infested fields with an over 51% incidence rate. The population density was determined in 41 samples with a mean of 79.5 cysts per 250 g of soil. These results will help to determine the control and management strategies of H. schachtii
Genetic architecture of kernel-related traits in sweet and waxy maize revealed by genome-wide association analysis
No full textIntroduction Maize (Zea mays L.) is one of the most important crops worldwide, the kernel size-related traits are the major components of maize grain yield.Methods To dissect the genetic architecture of four kernel-related traits of 100-kernel weight, kernel length, kernel width, and kernel diameter, a genome-wide association study (GWAS) was conducted in the waxy and sweet maize panel comprising of 447 maize inbred lines re-sequenced at the 5x coverage depth. GWAS analysis was carried out with the mixed linear model using 1,684,029 high-quality SNP markers.Results In total, 49 SNPs significantly associated with the four kernel-related traits were identified, including 46 SNPs on chromosome 3, two SNPs on chromosome 4, and one SNP on chromosome 7. Haplotype regression analysis identified 338 haplotypes that significantly affected these four kernel-related traits. Genomic selection (GS) results revealed that a set of 10,000 SNPs and a training population size of 30% are sufficient for the application of GS in waxy and sweet maize breeding for kernel weight and kernel size. Forty candidate genes associated with the four kernel-related traits were identified, including both Zm00001d000707 and Zm00001d044139 expressed in the kernel development tissues and stages with unknown functions.Discussion These significant SNPs and important haplotypes provide valuable information for developing functional markers for the implementation of marker-assisted selection in breeding. The molecular mechanism of Zm00001d000707 and Zm00001d044139 regulating these kernel-related traits needs to be investigated further
Adaptability, stability, and productivity of potato breeding clones and cultivars at high latitudes in Europe
No full textThe aim of potato breeding is to release cultivars that exhibit high and stable performance across the target population of environments. The objective of this research was therefore to investigate the use of various methods (site regression [SREG], coefficient of variation and regression deviation [sigma(2)(delta)]) for determining the adaptability and stability of productive and quality traits in the Nordic region of Europe. The multi-environment trials included 256 breeding clones and released cultivars grown by EU farmers at three distinct testing sites over two years in Sweden. There was significant (P < 0.001) variation in tuber yield, starch percentage and reducing sugars in the tuber flesh among the breeding clones and cultivars, testing environments and the genotype by environment interaction (GEI). The environments were very diverse, as revealed by the SREG biplots and particularly for the GEI patterns noted in terms of their productive and quality characteristics. The percentage of stable high-tuber yielding germplasm was greater for breeding clones (23%) than for released European cultivars (2%), thus revealing the advantage of potato breeding in the target population of environments. SLU 1415001 and SLU 1314015 were the most promising breeding clones due to their stable high tuber yield. This characteristic was best for the starch potato cultivars, although none of them exhibited a significant different sigma(2)(delta). 'Talent' shows an almost stable good performance among low reducing sugar cultivars and breeding clones, which are often unstable in terms of their scoring across environments. Neither a breeding clone nor a cultivar was at the top for stable tuber yield, tuber flesh starch or reducing sugars in the tuber flesh, which shows the challenge faced by potato breeding while addressing the needs of different markets
Achievements of CIMMYT’s Dryland Crops Program (DCP) in association with the Africa Dryland Crops Improvement Network (ADCIN) for the year 2023-2024
No full textThis document is a sample of ADCIN and DCP partnership achievements in 2023. We present them in sequence as per our theory of change because our work is motivated by a commitment to benefit farmers and consumers – to translate science into improved, resilient livelihoods. Our vision is effective regional crop improvement networks sustainably develop new crop varieties that benefit farmers, consumers, and other value chain actors through proven and innovative impact pathways.2 page
CIMMYT and Turkey: Daily bread from a deep-rooted partnership
No full textThe Green Revolution is generally associated with India and Pakistan but also had major impacts in the 1960s in Turkey, which imported 22,000 tons of the first semi-dwarf spring wheat varieties from Mexico, dramatically increasing national wheat production. Around the same time, winter wheat production also increased significantly due to the introduction of the Russian cultivar Bezostaya and new fallow management practices from the University of Oregon, USA. In 1986, the International Winter Wheat Improvement Program (IWWIP) was formed in Turkey as a partnership between the Turkish Ministry of Agriculture, CIMMYT, and ICARDA. In 2000, a joint Turkey-CIMMYT soil-borne disease program began.3 page