Source material from the VIR collection for hybrid breeding of multiple-ear maize

Background. Expanding the genetic polymorphism of maize is an effective way to increase its productivity by involving multiple-ear genotypes in breeding.Materials and methods. In 2007, 596 maize accessions from VIR were assessed at the Kuban Experiment Station of VIR. In 2020, 52 hybrids between multiple-ear and single-ear maize lines were tested in the steppe zone of Kabardino-Balkaria at the site of the OTBOR Agrifirm. Useful agronomic traits were recorded, the coefficient of prolificacy (kmc) was calculated for the source lines and their hybrid progeny from crosses with a single-ear tester, and 52 parent lines were ranked according to the type of inheritance of the prolificacy feature.Results. Accessions that combined prolificacy with other useful agronomic traits were identified. The following accessions were selected for their plant height (score 5, 126–175 cm): k-8819, k-9054, k-15269, k-15355, k-15360, k-15331, k-15877, k-15442, k-15443, k-15445, k-8009, k-14344, k-15195, k-15226 and k-17385. Accessions that excelled in the height of the ear attachment for mechanized harvesting (score 5, 50–70 cm) were as follows: k-8819, k-15269, k-15355, k-15360, k-14394, k-14904, k-14979, k-14968, k-15292, k-15391, k-9289, k-15322, k-15439, k-15442, k-15443 and k-14344. Sources of the following traits were identified: long cob (score 9, > 20 cm): k-9054, k-4535, k-13730, k-14817 and k-14996; higher number of rows per ear (score 5–9, > 16 grain rows): k-14904, k-14979, k-14968, k-15442, k-15330, k-15322 and k-9257; and higher number of grains in a row (score 5–9, > 31 grains per row): k-14904, k-14996, k-15639, k-15353, k-15330, k-15322, k-15344, k-15281, k-15439, k-9357 and k-15237. Ranking 52 accessions according to the test cross results showed that 9 of them produced progeny of the maternal type (no more than one ear), 26 of the intermediate type (1.1–1.5 ears per plant), 11 of the paternal type (1.6–2,0 ears) and 6 of heterotic type (more than 2 ears).

Evaluation candidate of test cross hybrid QPM under ecosystem of Polewali Mandar West Sulawesi

Abtract. Quality Protein Maize (QPM) was specialty maize which is high content of lysine and tryptophan. These are two essential amino acids better nutritional for human body to anticipated of disease (kwashiorkor) on severe among children, and could be corrective use in balancing diets. The experiment on 2018 has been conducted to evaluated of nine candidate test cross hybrid of QPM vs. check Bima 13Q with CRD three replications under lowland in distrit of Polman West Sulawesi. Genetic material were planted in four rows 5.0 m lenght, spacing 75x20 cm, and applied fertilizer Urea, Ponska (300-200) kg/ha. The result shown that two test cross F1 QPM were (MSQ(S1)C0-26-1-1 x MR14Q) and (MSQ(S1)C0-43-1-1-1 x MR13Q) which the best with potential yield 10.66-10.95 t/ha. The LSD shown that there are significant different with check Bima 13Q on yield (wc.15%) and highly 30.0% and 31.6%. The two candidates were founded shelling percentage 77.9% and 79.0%, asi less than five days and could be promising as new variety and continuing in evaluation variety trial (evt) in west Sulawesi.

Genetic analysis of low-n traits in maize (Zea mays L) using triple test cross

Low-N maize variety is developed for its ability to tolerate low nitrogen soil environment. This experiment was conducted to study the genetic implication of Low-N maize variety for grain yield and related traits under low nitrogen soil conditions triple test cross analysis. Inbred lines used for the study were generated from twelve low nitrogen tolerance open pollinated maize varieties after six generations of selfing. Two inbred lines along with their F1 were used as testers for ten inbred lines in a triple test cross pattern to generate 30 crosses. The 30 crosses, their parents and the testers to State University, Ado-Ekiti during 2017 planting season. The experimental design was a Randomized Complete Block Design (RCBD). Data were collected on plant height, ear height, days to 50% anthesis, days to 50% silking, incidence of curvularia leaf spot, blight, plant aspect, ear aspect, ear rot, stay green, cob per plant, ear weight, grain moisture content and grain yield. All data were subjected to analysis of variance and complete genetic estimates. Additive and dominants were significant (P < 0.05) for all traits; however, epitasis estimates were not significant for all the traits tested. The degree of dominance component indicated partial dominance for all the traits. Correlation coefficients for days to 50% anthesis and 50% silking, plant height, ear height, number of cobs per plant and grain yield were positive and significant (P < 0.05). Since both additive and dominance gene actions were important for low-N traits, the use of reciprocal recurrent selection procedure can be adopted in incorporating the trait into elite maize varieties.

Breeding Tomato Hybrids for Flavour: Comparison of GWAS Results Obtained on Lines and F1 Hybrids

Tomato flavour is an important goal for breeders. Volatile organic compounds (VOCs) are major determinants of tomato flavour. Although most tomato varieties for fresh market are F1 hybrids, most studies on the genetic control of flavour-related traits are performed on lines. We quantified 46 VOCs in a panel of 121 small fruited lines and in a test cross panel of 165 hybrids (the previous panel plus 44 elite cherry tomato lines crossed with a common line). High and consistent heritabilities were assessed for most VOCs in the two panels, and 65% of VOC contents were strongly correlated between lines and hybrids. Additivity was observed for most VOCs. We performed genome wide association studies (GWAS) on the two panels separately, along with a third GWAS on the test cross subset carrying only F1 hybrids corresponding to the line panel. We identified 205, 183 and 138 associations, respectively. We identified numerous overlapping associations for VOCs belonging to the same metabolic pathway within each panel; we focused on seven chromosome regions with clusters of associations simultaneously involved in several key VOCs for tomato aroma. The study highlighted the benefit of testcross panels to create tasty F1 hybrid varieties.

Detection of Epistasis and Genetic Parameters of Some Quantitative Traits Through Triple Test Cross Analysis in Chickpea (Cicer Arietinum L.)

Triple test cross analysis was carried out to detect the epistasis of thirteen yield and yield components in five chickpea (Cicer arietinum L.) crosses. Total epistatic effect was found to be non-significant for all the studied traits. Partitioning of total epistasis indicated the involvement of ‘i’ type (additive × additive) epistasis for DFF, PHFF, PWH, NPd/P, PdW/P, NS/P and SW/P in cross-1; NPBFF and NSBFF in cross-3 and for PHFF, DMF, PHMF and NSBMF in cross-5. The magnitude of additive component (D) was higher than that of the dominance component (H). Partial degree of dominance (√H/D) was observed for most of the traits. Both broad (h2b) and narrow (h2n) sense heritability were found to be moderately high. Positive and significant correlation between sums and differences indicated the direction of dominance towards decreasing parents and vice-versa. Bangladesh J. Bot. 50(2): 351-358, 2021 (June)

Pengaruh Latihan Memukul Memakai Beban Karet Terhadap Kecepatan Pukulan Dalam Olahraga Karate (Survey dalam Pembelajaran Mata Kuliah Karate)

Penelitian ini bertujuan untuk memperoleh gambaran tentang pengaruh yang ditimbulkan oleh latihan memukul dengan berbeban karet terhadap kecepatan pukulan dalam olahraga karate. Penelitian ini menggunakan desain randomized group pretest post test Cross group design. Populasinya adalah pemain karate tingkat lanjutan yang ada pada perkumpulan/perguruan Institut Karate-do Nasional (INKANAS) ranting Universitas Negeri Makassar. Sampel dipilih 50 orang dari 132 orang anggota populasi. Data yang terkumpul adalah hasil tes kecepatan pukulan. Hasil tersebut dianalisis secara statistik deskriptif selanjutnya dengan uji t. Hasil dari pengolahan data menunujukkan bahwa ada pengaruh yang diakibatkan oleh latihan memukul menggunakan beban karet yaitu rata-rata meningkat 6 unit kecepatan pukulan. Sedangkan pengaruh yang ditimbulakan oleh latihan tanpa beban karet hanya meningkat 3 unit kecepatan pukulan. Dengan demikian latihan tzuki berbeban karet lebih baik dari pada latihan tzuki tanpa beban karet. Urutan latihan fisik yang efektif adalah dimulai dengan latihan berbeban karet kemudian latihan tanpa penggunakan beban karet karena dapat mempengaruhi kecepatan pukulan secara rata-rata meningkat 7,70 unit kecepatan pukulan, sementara latihan memukul tanpa beban karet dilanjutkan latihan memukul dengan beban karet hanya meningkat secara rata-rata sebanyak 4,40 unit kecepatan pukulan.

Revelation of Epistasis through Triple Test Cross (TTC) Analysis in Rice (Oryza sativa L.)

Background: An investigation was performed to identify epistasis, additive, dominance components of genetic variation and yield and yield variability attributing characteristics by triple test cross testing involving three testers (P1, P2 and F1) and ten rice lines.Methods: The study materials consisted of F1 seeds of three crosses, involving six parents namely, ASD16, ADT47, ASD18, CO51, TKM9 and MTU 7029. They are evaluated in randomized complete block design with three replications. Observations were reported for seven traits, namely plant height, number of tillers per plant, number of productive tillers per plant, length of panicle, number of grains per panicle, weight of 1000 grains and yield of grain per plant on five randomly selected plants per replication.Result: The segregating population of three crosses exhibited wide range of variability for most of the traits. The difference between GCV and PCV was low for most of the characters indicated less influence of environment. Among the three crosses ASD18 x CO15 recorded high percent of heritability and genetic advance for grain yield per plant. The estimate of total epistasis revealed that i type of epistasis (additive x additive) was highly significant for number of tillers per plant, number of productive tillers per plant, panicle length and 1000 grain weight. The effect of the additive (D) variance was very important for all the traits except the number of grains per panicle. Across all traits, the degree of dominance (H / D)1/ 2 was less than unity ( less than 1) suggesting, partial of dominance. Since, the pre dominance component of epistasis in autogamous crop is additive x additive (i type), it was suggested that the selection may be post ponded to later generation until all the non-additive components of variance has been mitigated to additive components.

Inheritance of plumage colour in the F1 and test cross progeny of Japanese quail

Recessive genes produced its phenotypic effect only when its allele is identical while the dominant ones produced its effect either with identical or dissimilar alleles. This study was conducted to determine the mode of inheritance of plumage colour in Japanese quail flock in Nigeria, using the Manchurian Gold (MG), Pharaoh (PH) and Panda White (PW) plumage types. All possible crosses were made among the three colour variants making a total of nine mating groups. A total number of 2,348 F1 chicks and 1,563 test cross progeny obtained from the incubated eggs were classified and counted by their down colour into observable plumage colour groups. The expected phenotypic ratios of the F1 and test cross progeny were computed based on the assumption that parents that were homozygous for a particular plumage colour breed true. The results revealed that the Pharaoh plumage quails carry the wild-type allele (Wb) in homozygous form or in heterozygous with the Panda White (wb) allele. The Manchurian gold plumage quails carry the Manchurian Gold-type allele (Wb+) in heterozygous with either Wb or wb. All the Panda White chicks were homozygous for the wb allele, which was recessive to both Wb and Wb+ alleles. The Chi-square results confirm the heterozygousity of the dominant phenotype in the test crosses. It can be concluded that inheritance of plumage colour is controlled by autosomal genes with dominant hierarchy of MG> PH> PW (Wb+ >Wb>wb).

Relationship Between Combining Ability, Genetic Components And Genetic Diversity Using Triple Test Cross

Background: The target of this study is to investigate the relationship between genetic components, combining ability and genetic diversity among twenty six cotton crosses derived from a cross between thirteen contrasting inbred lines with two testers in three replications using modified triple test cross model.Results: All the genotypes showed highly significant differences for twelve yield and fiber quality traits reflecting genetic variability between lines, testers and crosses. Giza 86 is considered as a good combiner for yield and its components traits, while Giza 45 is the best combiner for fiber fineness and fiber strength, which classified in unique cluster. Most of the combinations having significant SCA effects were belonging to genetically diverse parents. The mean squares for the deviations revealed the presence of significant epistasis for all the studied traits except, seed index and fiber reflectance. While, significant mean squares were shown for sums and differences except lint index for additive and uniformity ratio and fiber reflectance for dominance. The fixable type (i) of epistasis was larger than non-fixable (i + l) type for the inheritance of the studied traits. The traits had significant mean squares for both fixable and non-fixable gene action, also showed significant GCA and SCA among 15 parents and 26 cotton crosses, respectively. Additive genetic component was larger than dominance for all the studied traits. So, most of the studied traits had significant GCA and degree of dominance was less than unity for all the studied traits, indicating partial or incomplete dominance. The correlation coefficient between the sums and difference were found to be insignificant indicating the genes with positive and negative effects were equally distributed among the genotypes.Conclusions: Genetic correlation between three genetic components revealed that both additive and epistasis play a great role among some studied traits suggesting common genetic pool. Thus, selection based on additive gene action based on indirect selection could improve cotton yield. The genotypes which have large genetic diversity could produce significant general or specific combining ability which may be reflecting its genetic behavior.