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Given climate change and population growth, it is increasingly important to efficiently grow food crops such as tomato (Solanum lycopersicum) using less irrigation water, a limited resource. Cultivated tomato is susceptible to water stress. In contrast, wild tomato species such as S. habrochaites and S. pennellii are water stress tolerant. The overall goal of this dissertation research was to investigate specific chromosomal regions of S. habrochaites and S. pennellii that are associated with water stress tolerance in the field and their potential use in breeding cultivated tomato. Indirect measures of water stress tolerance were employed, including carbon isotope discrimination (∆13C, an indirect measurement of water use efficiency, WUE), shoot dry weight, and yield to evaluate the various tomato genotypes derived from these two wild species that were grown under field conditions.In chapter one, the goal was to fine map quantitative trait loci (QTL) for maturity, yield, shoot dry weight, and ∆13C on chromosome 9 of S. habrochaites using a set of 21 sub-near-isogenic lines (sub-NILs) in a cultivated tomato background. These sub-NILs and control lines were evaluated in replicated field experiments grown under full and reduced irrigation treatments across two years. Significant QTL were detected for 20 trait-environment combinations. All QTL were partially or completely coincident. The presence of the S. habrochaites allele at QTL was associated with later maturity, lower yields, and greater WUE. Further mapping work is required before these QTL can be implemented in a marker assisted breeding program.In chapter two, cultivated tomato lines containing wild species chromosome introgressions (introgression lines, ILs) on chromosomes 2, 5, and 9 from S. habrochaites and S. pennellii were studied in various combinations in hybrid progeny. The goal was to determine if hybrid combinations of ILs with introgressions from S. habrochaites and S. pennellii improved WUE of genotypes compared to their parent ILs and/or inbred cultivated tomato varieties. A total of 35 genotypes (including two inbred tomato cultivars, homozygous ILs, heterozygous ILs, and hybrids between the two species ILs) were evaluated in the field for maturity, horticultural, yield, and WUE-related (∆13C) traits across two years under full and reduced irrigation treatments. General and specific combining abilities were calculated for the hybrid offspring in a Design II mating design. Hybrids generally had best-parent heterosis for yield, but not ∆13C. Three genotypes had better WUE than both cultivated tomato controls for the genetic background and did not cause significant reductions in yield. Some introgressions that showed positive effects on WUE also exhibited negative effects on other traits, such as fruit weight or maturity. Specific introgressions from both wild species may prove useful for developing hybrid tomato varieties that have acceptable yields yet use less irrigation water in the field.In chapter three, a de novo whole-genome sequence (WGS) of S. habrochaites accession LA1778 was generated using the PacBio RSII system and a Bionano optical map. Twelve pseudomolecules, corresponding to the 12 chromosomes of tomato, were constructed with a total length of approximately 959 Mb. The S. habrochaites WGS had high gene and sequence synteny with the S. lycopersicum reference annotation and sequence, although some inversions were detected. The S. habrochaites chromosome 9 sequence was used to determine the physical locations of previously mapped QTL for tolerance to rapid-onset water stress (stm9), WUE (∆13C), and other horticultural traits. A list of potential genes within each QTL interval was generated using S. lycopersicum genes that mapped to each interval, predicted genes, as well as mapped transcript reads from S. habrochaites acc. LA1777. It is likely that many of these genes can be affected by water stress and some may play a role in the tolerant phenotypes. Further work is required to determine which genes confer the slow-onset and rapid-onset water stress tolerant phenotypes.Some of the wild genomic regions have both negative and positive effects on horticultural traits (i.e., linkage drag). Additional studies need to be conducted to fractionate the QTL that are in repulsion phase linkage. High-resolution QTL mapping can lead to the integration of positive WUE-related loci without negative horticultural effects via marker assisted selection. Collectively, these studies support the conclusion that S. habrochaites and S. pennellii have potential promising uses for breeding cultivated tomato with improved water stress tolerance.

Wheat (Triticum aestivum L.) is the most important crop for human nutrition that underpins the food safety of Saudi Arabia. The investigation here was to determine heterosis effects using different genetic methods: heterosis over better, mid parents, the genetic advance, and genotype, phenotypic coefficient of variation for estimation some traits among six wheat landraces and their F1 hybrids. In 2019, these landraces were sown using hand and after 100 days, the emasculation and crossing were made among these six landraces using hand emasculation of anthers. In 2020, seeds for these genotypes (six wheat landraces and their F1) were sown under normal irrigation accordingly done in 2019. The results showed that the most important parent was Mabia resulted with the highest value in number of tiller/ plant, 1,000-grain weight, and fresh shoot weight. The highest value of plant height among six parents was Naqra while highest value at the same trait among F1 hybrids was P3 XP6. The estimations of heterosis showed that out of 15 crosses, one cross (P1XP5) was significantly better yield than all crosses for these four traits. The genotype coefficient of variation (GCV) ranged from 12.5% to 8.7% while phenotypic coefficient of variation ranged from 17.7% to 11.3%. The correlation coefficients was found between fresh shoot weight and number of tiller and plant height and umber of tiller. Wild wheat still serve as a source of useful germplasm with proven adaption and productivity and thus assembles of the wild wheat assortments are the initial step of breeding program.

The aim of this work is to study tomato sorters with contrasting complementary in hybridization of morpho-biological properties favorable for the expression of the effect of heterosis. Novelty. Tomatoes as a culture are quite plastic and easily adapted to the most diverse soil-climatic conditions of cultivation. Detectable natural mutations were easily fixed by screenings and gave rise to new and new forms. These changes concerned many signs and properties and allowed practically to design tomato plants for specific human needs. Methods. The studies included stamp varieties: Shtambovyy 5 and Fonarik, medium-ripe Kuban 557 and medium late-ripe Volgogradskiy 5/95 and Krasnodarets 87. The test was carried out in comparison with the best districted varieties (standards) in irrigated conditions. Results. By the nature of growth, the greatest habitus was observed in the parent line LS 2/11 164.6, which is a consequence of the subsequent orders of branching and the inflorescences formed on them, providing the highest yield of this line. According to the analysis of interactions, the year and genotype for the conditions of the year strongly determine the mass of fruits from one plant (66.1 %), while the number of fruits and the average weight of the fruit are determined mainly by the genotype: 92.8 and 73.2 %, respectively. The number and size of fruits are signs with strong genetic determinancy, which are components of the mass of fruits, which shows a strong dependence of the latter indicator on the conditions of the year. When combining optimal productivity indicators, they also showed the least variability, which is of considerable practical interest.

Eleven genotypes of bread wheat were crossed with three testers in the rabi season of 2018-19 inline x tester mating fashion to obtain 33 F1 hybrids, which were evaluated with parents and two standard checks of wheat viz., UP 2855 and HD 2967. The experiment was laid out in randomized block design with three replications at Norman E. Borlaug Crop Research Centre, G.B. Pant University of Agriculture and Technology, Pantnagar in the rabi season 2019-20. Observations were recorded on various qualitative and quantitative characters including grain yield. The results obtained revealed significant differences among all the genotypes, indicating the presence of aconsiderable amount of genetic variability. The cross combinations SOKOLL x HI 1621, followed by QBP 12-11 x HI 1621, NAC/TH.AC//3*PVN/3/MIRLO/BUC/4/ 2*PASTOR/5/… x HD 3237 were observed to be the better heterotic F1s in terms of grain yield. The hybrid QLD 75 x HI 1621 was identified as the best heterotic combination for grain weight per spike and harvest index. Whereas, for grains per spike F1, NW 6036 x HI 1621, for 1000 grain weight F1, SOKOLL x HD3237, for spike length F1, NAC/TH.AC//3*PVN/3/ MIRLO/BUC/4/2*PASTOR/5/… x HD 3237, for peduncle length F1, VORB/4/D67.2/PARANA 66.270 x HI 1621 and for days to 75% heading and days to maturity F1, PRL/2*PASTOR*2//FH6-1-7/3/KINGBIRD#1//… x PBW 725 were observed to be the better heterotic combinations. The crosses with higher heterotic values may provide an opportunity for isolation of desirable purelines in advanced generations.

Thirteen lines and three testers were used to produce 39 single cross maize hybrids by line Ítester mating design. The genetic divergence among thirteen lines and three tester of maize were estimated by using Mahalanobis D2 statistic for twelve characters. The genotypes were grouped into five clusters. Cluster I comprised 12 parental genotypes (L1, L2, L3, L4, L5; L6, L7, L8, L9, L11; L12, L13), while Cluster II (T3), III (T1), IV (L10) and V (T2) were mono-genotypic, suggesting more variability in genetic makeup of the genotypes included in these clusters. The correlation coefficients and linear regressions were used to know the effects of parental genetic distance in determining heterosis and per se performance of the hybrids. Parental genetic distance exhibited significant negative association and significant linear regression along with very low coefficient of determination with better parent heterosis (BPH) and non-significant with per se performance of the hybrids. The present investigation, therefore, the parental genetic distance has significant role in determining heterosis and hybrid performance in kharif maize.

Variability gives room for recombination which is important for any crop improvement program. Based on this contextual, this work was conducted to evaluate genetic variability among groundnut germplasm and establish relationships between oil quality and agronomic traits using multivariate analysis. To achieve this objective, fifteen groundnut genotypes were evaluated in a randomized complete block design with three replications. Data were collected on oil and yield quality traits. The estimates of genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) were high for number of pods and number of seeds per plant, carbohydrate and protein. Broad sense heritability estimates for agronomic and oil content traits ranged from 49.57% - 99.06% while the genetic advance expressed as percentage of mean estimates ranged from 17.73% -114.38%. The evaluated genotypes were clustered into four main groups based on oil and yield quality traits using UPGMA dendrogram. Hence, hybridization of group II with either group I, III or IV could be used to achieve higher vigor or heterosis among the genotypes. The number of pods per plant showed a significant correlation with pod weight per plant (r =0.79) and the number of seeds (0.99). However, most of the oil content traits recorded a non-significant negative correlation. It was concluded that number of pods, seeds per plant, and fat content might be the major agronomic and oil quality traits as selection criteria for improving groundnut genotypes. Also, this assessment could be used in development of reliable selection criteria for important agronomic traits in groundnut

In the present study, line× tester analysis was carried out at Castor-Mustard Research Station, S. D. Agricultural University, Sardarkrushinagar, Gujarat, India during rabi 2018–19 (October 2018 to February 2019) in order to estimate all three types of heterosis (relative heterosis, heterobeltiosis and economic heterosis) for identification of superior cross combinations of Indian mustard [Brassica juncea (L.) Czern&Coss]. Thirty-five hybrids along with five CMS lines, seven testers and check GDM 4 were evaluated for ten different traits. The F1 generation of all the crosses exhibited fertility restoration with pollen fertility except F1 crosses with Vardan, Rohini and SKM 319 fertile line (0%). The remaining crosses exhibited pollen fertility ranging from 68.26% (Kranti×SKM 303) to 85.17% (Kranti×Mori ‘R’ 1-18). The analysis of variance for parents, hybrids and parents vs. hybrids revealed that mean sum of squares of parents were highly significant for majority of the characters except days to maturity. Whereas, hybrids differed highly significant for all the characters. Comparison of mean squares due to parents vs. hybrids was found significant for almost all the characters except number of seeds siliqua-1 and oil content. This indicates that considerable amount of genetic variability present among the parents and hybrids for all the characters studied. On the basis of per se performance, three hybrids viz., Kranti×Mori ‘R’ 1-18, SKM 9928×PusaAgrani and SKM 9928×Mori ‘R’ 1-18 were foundpromising for seed yield plant-1 over the standard check GDM 4.With respect to heterosis, one of the hybrid Kranti×Mori ‘R’ 1-18 (17.85 %)manifested significant and positive standard heterosis for seed yield plant-1.

The present investigation entitled “Studies on Heterosis for Yield and Yield Contributing Traits in Desi Cotton (Gossypium arboreum L.) was undertaken with the objective to study the scale of heterosis over mid parent (Average heterosis), better parent (Heterobeltiosis) and standard check (Standard heterosis). The line x tester method of analysis was followed involving four females viz., PA 811, PA 839, PA 808 and PAIG 380 and six males viz. AKA 8, JLA 505, PA 812, AKA 7, PA 08 and Phule Dhanwantry for study of heterosis for various yield and yield contributing characters. The F1’s and theis parents were evaluated in Randomized Block Design with two replications. Observations were recorded on Days to 50 % flowering, Plant height (cm), Number of sympodia, Number of bolls/plant, Boll weight (g), Seed index, Seed cotton yield/plant (g) and Lint index. The magnitude of heterosis was highest for seed cotton yield per plant, which was recorded to the extent of 115.28 % over standard check PKV Suvarna in the cross PAIG 380 x AKA 8 followed by 109.68 % over standard check PKVDH 1.

The experimental material comprised of thirty two crosses along with twelve parents (four lines and eight testers) and standard checks AHB 1200 Fe and AHB 1269. The experiment was laid out in Randomized Block Design with two replications. The observations were recorded on ten characters viz., days to 50 per cent flowering, days to maturity, plant height, number of effective tillers, earhead length, earhead head girth, downey mildew, 1000 grain weight, grain yield and fodder yield. The analysis of variance revealed that there were significant differences among the parents and crosses for all the characters studied. Considering the heterosis ICMA 00888 X AUBI 15236, ICMA 00888 X AUBI 15157, ICMA 06777 X AUBI 15051 and ICMA 00888 X AUBI 15026 appeared to be the more promising hybrids for breeding.

Studies were carried out in order to identify the features of morphogenesis in triticale populations under conditions of increasing climate aridity. The work was carried out in 2010–2020 in the northwestern zone of Rostov oblast on chernozems on bare fallow. Hybrids, populations, and lines of winter triticale grain crops were studied in a total of 3001 combinations of intraspecific crosses and 57 distant crosses. Generally accepted pedigree and bulk breeding methods were used. The breeding nursery was laid with unthreshed ears. The frequency of transgressions in hybrid offspring of intraspecific combinations increased from F3 to F6–9, while it remained high, up to F10–12, in some combinations. The peak of the frequency of transgressions in distant hybrids was at F7 and F12–14. In the breeding nursery (BN), 299 000 families of intraspecific origin were studied, and 4278 lines were studied in the control nursery (CN). The effectiveness of the selection of promising crossovers was 1.4% in the BN and 15.2% in the CN. The selection efficiency in distant offspring was 1.8 and 18.0%. The recombination process in triticale can last up to 18 generations, especially during distant hybridization. Its duration depends on the original components of the crossing. Combinations with heterosis in terms of productivity in the first generation are promising in the future. The degree of dominance of the grain mass per plant can serve as an indicator of the breeding value of the combination. As a result of the research carried out during the period under study, ten varieties of triticale were bred (Gektor, Almaz, Atstek, Donslav, Kapral, Piligrim, Aznavur, Argus, Arion, etc.). The high-carotenoid variety Ramzes was created using winter bread wheat as one of the parents. All varieties, with the exception of the Ramzai variety, were bred with two or three selections, which once again confirms the high efficiency of repeated selections in the selection of triticale.

DROUGHT is a worldwide problem which controls the crop productivity. Six Egyptian bread wheat varieties were crossed in a 6x6 half diallel in 2018/19 season. Parents and their fifteen F1 crosses were evaluated under normal irrigation (N), mid water stress (MS) and severe water stress (SS) during 2019/20 in three field experiments. Results showed that the analysis of variance were significant for all the studied traits. The highest mean values were recorded under all irrigation treatments as well as the combined analysis with the crosses P1x P2, P1 x P3, P1 x P5, P2 x P3, P3 x P5 and P5 x P6 for grain yield per plant. Mean squares for both general (GCA) and specific (SCA) combining ability estimates were highly significant for all studied traits. GCA/SCA ratio was greater than unity for most traits. The parental P1 exhibited positive and significant GCA effects for number of kernels per spike, grain yield per spike and grain yield per plant. The highest desirable SCA effects were obtained with the crosses P3 x P5 and P4 x P5 for grain yield per plant under stresses conditions. Positive significant heterosis were detected by the crosses P1 x P3, P2 x P3, P3 x P5, P4 x P5 and P5 x P6 for number of spikes per plant, number of kernels per spike, grain yield per spike, 1000-grain weight and grain yield per plant at N, MS, SS conditions and the combined data.

Rice restorer line is one of the important parents for the utilization of rice heterosis. An excellent restorer line is the basis for breeding super hybrid rice. Rice chromosome segment substitution line (CSSL) based on excellent restorer lines is an ideal material for both genetic research and breeding practice due to its consistent genetic backgrounds besides few substitution segments from donor. Here, a short-wide grain rice CSSL-Z752 was developed using the excellent line Xihui 18 as the recipient parent and Huhan 3 as the donor parent by advanced backcrossing and self-polling combined with simple sequence repeat (SSR) marker-assisted selection. Z752 contained 13 substitution segments from Huhan 3 with 3.69 Mb of average substitution length. Compared with the recipient Xihui 18, the number of effective panicles per plant, grain width, 100-grain weight and yield per plant in Z752 increased significantly, and grain length of Z752 was decreased significantly than that of Xihui 18. The other traits showed no significant difference. Then, the secondary F2 population crossed by Xihui 18 and Z752 was used to map 10 QTLs for the important agronomic traits, which were distributed on the chromosome 2, 3, 4, 5, 6, 7, 10, 11, and 12. Among them, there were two QTLs for effective panicle number per plant, plant height and grain width, respectively, including QPN3, QPN5 and QPH2, QPH6, QGW2, QGW5, and one QTL for grain number per panicle, seed-setting rate, grain length, ratio of grain length to width, respectively, including QGP2, QSSR2, QGL3 and QRLW5. The results will be of great significance for development of single-segment substitution lines carrying target QTL sand breeding of hybrid rice.

Рассмотрены важные аспекты использования геноносителей различных маркерных признаков при создании и селекции гетерозисных гибридов томата для защищенного грунта. Наряду с общими требованиями к родительским компонентам, касающимися продуктивности растений, скороспелости, устойчивости к болезням и т. д., сегодня при селекции на гетерозис для защищенного грунта к исходному материалу предъявляют более высокие требования по наличию хозяйственно полезных признаков. Эти требования касаются типа роста растений, формы, окраски и качества плодов, типа кисти, формы плодоножки и т. д. Представлены характеристики исходного материала для создания гетерозисных гибридов томата, а также даны характеристики полученных гибридов. Исследования, проведенные в отделе селекции ВНИИО (ВНИИ овощеводства – филиал ФГБНУ ФНЦО), показали большую перспективность использования при гетерозисной селекции томата для защищенного грунта геноносителей различных маркерных признаков, особенно признаков, определяющих коричневую окраску эндосперма семян (гены bs и bs-2) и несочлененную плодоножку (ген j-2). Созданные с использованием этих маркерных признаков гибриды и селекционные линии по-своему уникальны и являются приоритетным достижением этого научного учреждения, так как они представляют большой интерес для гетерозисной селекции томата в качестве исходного материала. Целый ряд гибридов F1 включен в Госреестр селекционных достижений, допущенных к использованию (Удача, Голубчик, Клад овощевода, Заур и др.). В связи с развитием фермерского и любительского овощеводства в последние годы определенное внимание было уделено созданию новых мутантных линий с розовыми, малиновыми и темно-коричневыми плодами с высокими вкусовыми качествами (учитывая, что образцы такого типа пользуются повышенным спросом у населения и стоят дороже). При создании новых гетерозисных гибридов были учтены эти признаки родительских форм. Important aspects of the use of gene carriers of various marker traits in the creation and selection of heterotic tomato hybrids for greenhouse industry are considered. Along with the general requirements for the parent components concerning plant productivity, precocity, resistance to diseases, etc., today, when breeding for heterosis for greenhouse industry, higher requirements are imposed on the source material for the presence of economically useful features. These requirements relate to the type of plant growth, shape, colour and quality of fruits, brush type, stem shape, etc. The characteristics of the initial material for creating heterotic tomato hybrids are presented, as well as the characteristics of the resulting hybrids are given. Studies conducted in the breeding department of the ARRIVG (ARRIVG – a branch of the FSBI FSCV) showed great prospects for the use of gene carriers of various marker traits, especially those that determine the brown colour of the seed endosperm (bs and bs-2 genes) and an undifferentiated peduncle (j-2 gene) in the heterosis breeding of tomatoes for greenhouses. Hybrids and breeding lines created using these marker traits are unique in their own way and are a priority achievement of this scientific institution, since they are of great interest for the heterosis breeding of tomato as a basic material. A number of F1 hybrids are included in the State Register of Breeding Achievements allowed for use (Udacha, Golubchik, Klad ovoschevoda, Zaur, etc.). Due to the development of farming and amateur vegetable growing in recent years, some attention has been paid to the creation of new mutant lines with pink, crimson and dark brown fruits with high taste qualities (given that samples of this type are in high demand among the population and are more expensive). When creating new heterotic hybrids, these features of the parent forms were taken into account.

The Prairie Pothole Region (PPR) of North America has experienced extreme changes in wetland habitat due to proliferation of invasive plants. Typha × glauca is a highly competitive hybrid between native T. latifolia and non-native T. angustifolia, and it is likely the predominant taxon in PPR wetlands. Genetics-based studies are limited, and distributions are poorly known for the first-generation (F1) hybrid and advanced-generation hybrids from F1 mating. Information pertaining to the distribution of T. × glauca could benefit efforts to understand the mechanisms of its spread and to develop management strategies to limit hybrid expansion and preserve progenitors. We used microsatellite markers of field-collected tissue samples from 131 wetlands spread over approximately 350,000 km2 in the PPR to assess the distribution of hybrid T. × glauca relative to its parental species and to examine the prevalence of F1 hybrids and advanced-generation hybrids. Typha × glauca was found in over 80% of wetlands throughout the PPR, compared to 26 and 18% of wetlands with T. latifolia and T. angustifolia, respectively. Advanced-generation hybrids were more common than F1 hybrids, suggesting that hybridization is not a recent phenomenon. Hybrids were significantly taller than T. latifolia, indicating heterosis. Only 7% of sampled individual genets were pure T. latifolia. These results suggest that T. × glauca is pervasive throughout the PPR and may spread independently of both parents. In addition, limited prevalence of native T. latifolia indicates the need for active management to preserve the species.

Provitamin A-enriched maize (Zea mays L.) is an important complementary food staple for combating vitamin A deficiency (VAD) in high maize-producing and maize-consuming countries of sub-Saharan Afr...

Purpose. To increase the performance of sugar beet hybrids using integrated approaches to the creation, identification and selection of combination-valuable parents; to evaluate the performance potential of experimental hybrids derived from parents with improved beetroot shape. Materials and methods. The study was conducted in the Laboratory of Sugar Beet Breeding of the Tobacco Experimental Station of the National Research Center “Institute of Agriculture of NAAS” in 2018–2020. Sixty-six experimental diploid sugar beet hybrids originating from parents of different genetic origin were tested in the field. New starting material of sugar beets was created using classical breeding methods and traditional techniques. The experimental CMS-based sugar beet hybrids were evaluated for several economically valuable traits in accordance with the variety trial method developed by scientists of the Institute of Bioenergy Crops and Sugar Beets NAAS. Results and discussion. Analysis of the performance of the sugar beet hybrids originating from the parents with improved beetroot shape (oval-conical) indicates that the beetroot yields, sugar collection and output were significantly higher than those in the group check accession. The sugar content in their beetroots was lower than or similar to that in the group check accession. In general, the yielding type (E) of performance is intrinsic to the hybrids. As to beetroot yield, they exceeded the group check accession by 16.5–23.4%; the sugar collection was higher by 15.1–21.1%; and the sugar output – by 15.0–22.0%. Analysis of the beetroot in these hybrids shows that they had oval-conical beetroots. Their shape index varied 1.11 to 1.24. The beetroots of these hybrids were embedded into the soil by 3/4 of their length, had a smooth surface and shallow grooves (orthostichy). In the experimental sugar beet hybrids derived from the parents with improved beetroot shape (oval-conical), beetroots were longer (L) by 9.5%, larger in the diameter (D) by 2.2%, and the distance from the maximum diameter plane to the beetroot top (B) increased by 61.5% compared to the group check accession. In parallel with changes of the beetroot shape, the beetroot weight (m) increased by 25.0%. The transition from conical beetroots to oval-conical ones was proven to increase the performance of the sugar beet hybrids by 15–21%. Conclusions. We have created 14 high-yielding sugar beet CMS-based hybrids with improved beetroot shape, suitable for energy and environmentally friendly cultivation technologies. Their beetroot yields, sugar collection and sugar output exceed those in the group check accession by 16.5–23.4%, 15.1–21.1% and 15.0–22.0%, respectively, Цель исследований – повышение продуктивности гибридов сахарной свеклы с использованием комплексных подходов формирования, идентификации и отбора комбинационно-ценных родительских компонентов. Оценка продуктивного потенциала экспериментальных гибридов сахарной свеклы, созданных на основе родительских компонентов с улучшенной формой корнеплода. Материалы и методика. Исследования проводили на Опытной станции табаководства ННЦ «ИЗ НААН» в лаборатории селекции сахарной свеклы в 2018–2020гг. К полевым опытам привлечены 66 экспериментальных диплоидных гибридов сахарной свеклы, созданных на основе родительских компонентов разного генетического происхождения. Создание нового исходного материала сахарной свеклы проведено с использованием классических методов селекции по общепринятым методикам. Экспериментальные гибриды сахарной свеклы на ЦМС основе изучены по комплексу ценных хозяйственных признаков соответственно методикам сортоиспытания, разработанных в Институте биоэнергетических культур и сахарной свеклы НААН. Обсуждение результатов. Анализ продуктивности гибридов сахарной свеклы, созданных на основе родительских компонентов с улучшенной формой корнеплода (овально-коническая) показывает, что по урожайности корнеплодов, сбору и выходу сахара они существенно превышают групповой стандарт. Сахаристость их корнеплодов была ниже или на уровне группового стандарта. В целом, гибриды характеризуются урожайным направлением (Е) продуктивности. По урожайности корнеплодов они превышали групповой стандарт на 16,5–23,4%, сбору сахара на 15,1–21,1% и выходу сахара на 15,0–22,0%. По анализу параметров формы корнеплода гибридов данного типа установлено, что они характеризуются овально-конической формой. Показатели индекса формы корнеплода в них варьировали в пределах 1,11–1,24. Корнеплоды этих гибридов заглублены в почву на 3/4 длины, имеют гладкую поверхность и мелкую корневую бороздку (ортостиху). У экспериментальных гибридов сахарной свеклы, сформированных на базе родительских компонентов с улучшенной формой корнеплода (овально-коническая), увеличилась длина корнеплода (L) на 9,5%, диаметр корнеплода (D) – на 2,2%, расстояние от плоскости максимального диаметра корнеплода до вершины головки (В) на 61,5% по сравнению с групповым стандартом. С изменением параметров формы корнеплода увеличилась и его масса (m) на 25,0%. Установлено, что изменение формы корнеплода родительских компонентов с конической на овально-коническую приводит к повышению продуктивности гибридов сахарной свеклы на 15–21 %. Выводы. Создано 14 высокопродуктивных гибридов сахарной свеклы на ЦМС основе с улучшенной формой корнеплода, пригодные для энерго- и экологощадящих технологий выращивания. Они превышают групповой стандарт по урожайности корнеплодов на 16,5–23,4%, сбору сахара на 15,1–21,1% и выходу сахара на 15,0–22,0%, Мета дослідження – підвищення продуктивності гібридів цукрових буряків із застосуванням комплексних підходів формування, ідентифікації та добору комбінаційно-цінних батьківських компонентів. Оцінка продуктивного потенціалу експериментальних гібридів цукрових буряків, створених на основі батьківських компонентів з поліпшеною формою коренеплоду. Матеріали і методика. Дослідження проводили на Дослідній станції тютюнництва ННЦ «ІЗ НААН» у лабораторії селекції цукрових буряків у 2018–2020 рр. Вихідним матеріалом для польових дослідів були 66 експериментальних диплоїдних гібридів цукрових буряків, створених на основі батьківських компонентів різного генетичного походження. Створення нового вихідного матеріалу цукрових буряків проведено із застосуванням класичних методів селекції за загальноприйнятими методиками. Експериментальні гібриди цукрових буряків на ЦЧС основі досліджено за комплексом цінних господарських ознак відповідно до методик сортовипробування, розроблених в Інституті біоенергетичних культур та цукрових буряків НААН. Обговорення результатів. Аналіз продуктивності гібридів цукрових буряків, створених на основі батьківських компонентів з поліпшеною формою коренеплоду (овально-конічною) доводить, що за врожайністю коренеплодів, збору та виходу цукру вони істотно перевищують груповий стандарт. Цукристість цих коренеплодів була нижчою або на рівні групового стандарту. В цілому, гібриди характеризуються врожайною спрямованістю (Е) продуктивності. За врожайністю коренеплодів вони перевищували груповий стандарт на 16,5–23,4%, збором цукру – на 15,1–21,1% та виходом цукру – на 15,0–22,0%. За аналізом параметрів форми коренеплоду гібридів даного типу встановлено, що вони є овально-конічними. Показники індексу форми коренеплоду в них варіювали в межах 1,11–1,24. Коренеплоди цих гібридів заглиблюються в землю на 3/4 довжини, мають гладеньку поверхню та мілку кореневу боріздку (ортостиху). В експериментальних гібридів цукрових буряків, сформованих на основі батьківських компонентів з поліпшеною формою коренеплоду (овально-конічною), збільшувалась довжина коренеплоду (L) на 9,5%, його діаметр (D) – на 2,2%, відстань від площини максимального діаметра коренеплоду до вершини голівки (В) на 61,5% у порівнянні з груповим стандартом. Зі зміною параметрів форми коренеплоду збільшилася і його маса (m) на 25,0%. Установлено, що зміна форми коренеплоду батьківських компонентів з конічної на овально-конічну призводить до підвищення продуктивності гібридів цукрових буряків на 15–21 %. Висновки. Створено 14 високопродуктивних гібридів цукрових буряків на ЦЧС основі з поліпшеною формою коренеплоду, придатних для енерго- та екологозберігаючих технологій вирощування. Вони перевищують груповий стандарт за врожайністю коренеплодів на 16,5–23,4%, збором цукру на 15,1–21,1% та виходом цукру на 15,0–22,0%

For the analysis of the results of hybridization during the early stages of wheat breeding, it is important to choose a system of traits by which the selection of elite plants will achieve some genetic progress and lead to improved yield potential. As a rule, when analyzing various factorial traits in the first-generation hybrids, quantitative parameters of plant yield components, their inheritance pattern, and heterosis are determined. A new source material of spring durum wheat was created by intraspecific and interspecific crossings. The inheritance pattern of the main components of spike productivity in the first-generation hybrids of durum wheat has been studied. The inheritance overdominance and partial positive dominance of spike length and grain number per spike was characteristic for the majority (64.3%) of intraspecific F1 hybrids. The best hybrid combination (Melanopus 10-02 × Slavuta) was characterized by overdominance and positive dominance in the inheritance of all the studied traits; high degree of heterosis (DH) (64.7%) by grain weight per spike was noted. Heterosis and inheritance pattern of the “1000 grain weight” trait by overdominance was found in hybrids obtained by crossing Melanopus 10-02 × Slavuta (hp = +5.0; DH +9.9%), Leucurum 06-07 × Saratovskaya zolotistaya (hp = +13.0; DH +7.4%), and Leucurum 06-07 × Kharkivska 29 (hp = +17.0; DH +10.0%). Among the studied parental component, the line Melanopus 10-02 has been selected and submitted to the State Qualifying Examination of the Ukrainian Institute for Plant Variety Examination. It was registered as the novel durum wheat cultivar MІР Raiduzhna. The promising perspective of the intraspecific cross combination (Line 08-17 × Saratovskaya zolotistaya) was noted; these hybrids were characterized by heterosis for all the analyzed traits and overdominance of their inheritance, which allowed recommending this cross for further genetic studies. Therefore, defining the parameters of plant productivity, the inheritance pattern, the degree of heterosis in the first-generation hybrids is an urgent task in creating new varieties as well as in the predicting breeding and genetic effect of crossing.

Rice, the number one staple food crop of Nepal, contributes nearly 20% to the agricultural gross domestic product, almost 7% to gross domestic product, and supplies with 40% of the food calorie consumption of Nepalese people. Despite of increasing production, the national demand of rice cannot be fulfilled, and billions of rupees are spent yearly for importing rice from India. This article reviews history, recent scenario, prospects, and importance of rice breeding research in Nepal for self-sufficiency. Though plant breeding inception point in Nepal was 1951, the systematic research in rice was started from 1972 after the establishment of the National Rice Research Program. Introduction and evaluation of high yielding exotic germplasm of rice was the initial rice breeding activities. After analysing several foreign materials, CH-45 variety of rice was first recommended in 1959. Nepal Agriculture Research Council (NARC), the leading organisation for rice varietal improvement to date, has been doing rice research activities such as germplasm conservation, exchange, varietal development, verification of technologies, and knowledge updates in collaboration with various organizations. International Rice Research Institute (IRRI), since 1966, has been playing an important role in Nepal’s rice research. Major plant breeding achievements are introduction of exotic materials and their evaluation, local landraces identification, collection and analysis, crossing of local landraces with exotic genetic materials, heterosis breeding, tissue culture technology, genetic marker technology, and National Genebank. RAPD and SSR, DNA-based markers, are mostly used for diversity appraisal and selecting desirable genotypes. Integration of advanced tools such as genetic engineering, bioinformatics, protoplast fusion, and SNP markers could not be still applied in rice research and development. Hence, emphasis should be given to improve the capacity and abilities of the rice scientists and should release more short duration, drought, and submergence-tolerant rice varieties by optimum utilisation of local landraces combining modern and conventional breeding.

Key message Faba bean genotypes showed significant and marked genetic differences in their success as pollen donors to cross-fertilized seeds. The findings may improve exploitation of heterosis in synthetic cultivars. Abstract In partially allogamous crops such as faba bean (Vicia faba L.), increasing the share of heterosis in a synthetic cultivar can improve yield and yield stability. The share of heterosis in such synthetic cultivars is increased by higher degrees of cross-fertilization. This trait is defined as percentage of cross-fertilized seeds among all seeds and is a crucial parameter in breeders’ yield predictions. Current approaches use degree of cross-fertilization to predict inbreeding and share of heterosis, they even consider genotype-specific degrees; yet, all genotypes are assumed to contribute equally to the cross-fertilized seeds. Here, we expect faba bean genotypes to differ in their success rates as pollen donors, i.e. in paternal outcrossing success. To quantify the variation of both, the degree of cross-fertilization and the paternal outcrossing success, we assessed these parameters in inbred lines and F1 hybrids, grown in four polycrosses composed of eight genotypes each. We identified the paternal genotype of 500 to 800 seeds per genotype and polycross using SNP markers. In both traits, we found marked and significant variation among inbred lines and among F1 hybrids, as well as between inbred lines and F1. Based on our findings, we discuss how differential paternal outcrossing success influences the amount of inbreeding in synthetic cultivars. Our findings offer the potential for a better management and exploitation of heterotic yield increase in faba bean.

Rice is a staple food for more than half of the world’s population and to increase the yield potential of rice would be a key factor for mitigating global demands of about 810 million tons of rice by 2025. To exploit the economic importance of heterosis, quantitative valuation was carried out in a randomized complete block design with three replications for 16 agronomic traits of 5x5 half diallel populations during boro season of 2017-2018. Diallel populations were generated by using five selected parents (P1: BRRI dhan28, P2: BRRI dhan74, P3: BINA dhan10, P4: IR59418-7B-21-3 and P5: BRRI dhan67) where, P1 was considered as standard check to estimate the economic heterosis. Analysis of variance revealed highly significant variability among the genotypes for most of the traits except grain length and length-breadth ratio. The results showed that none of the hybrid combination performed better for all the traits over the three types of heterosis. The highest relative heterosis was recorded in P3×P4 followed by P4×P5 for grain yield plant-1, filled grains panicle-1, effective tillers plant-1. Majority of the cross combinations (>60%) revealed highly significant positive heterosis for grain yield plant-1 over mid parent. Heterobeltiosis for grain yield plant-1 was observed significant for 50% cross combinations and could be utilized in hybrid breeding. Whereas, more than 70% crosses exhibited undesirable negative standard heterosis for grain yield plant-1. Only two cross combinations (P3×P5 and P3×P4) among ten revealed significant positive economic heterosis for grain yield plant-1 and those could be exploited in rice breeding. Int. J. Appl. Sci. Biotechnol. Vol 9(1): 45-53

A study was conducted to assess the extent of the heterosis for sixteen yield and yield-attributing traits in four cotton hybrids (each having P1, P2, F1, F2, BC1 and BC2 generations) obtained by crossing four interspecific lines of desi cotton in a compact family block design with three replications during kharif 2017-18. Highly significant and positive relative heterosis, heterobeltiosis and inbreeding depression were recorded in most of the crosses. For seed cotton yield per plant, positive and highly significant relative heterosis, heterobeltiosis and inbreeding depression were recorded in all the four crosses indicated major role of non-additive gene actions in the inheritance of seed cotton yield per plant and its attributes, while cross III (GShv 362/12 x PA 812) recorded the highest heterotic effect among all crosses which also performed well for monopodia per plant, average boll weight, lint yield per plant, ginning percentage, lint index, fibre fineness and fibre strength.

Six wheat varieties were single crossed at 2017/18. Six parents and its 15 F1 single-crosses were cultivated under N-normal and N-stress at 2018/19, to study heterosis and the genetic parameters for yield and its components under normal and N-stress. Mean squares of wheat-gentypes, parent, F1-crosses and parent versus cross were highly significant or significant for most of traits under both conditions. The highest desirable heterosis and heterobeltiosis were detected by crosses No. 7 and No.8 for earliness; No.14, No.8 and No.3 for 100-Grain weight; crosses No.8 and No.13 for number of spikelets/spike; crosses No.9, No.7 and No.13 for number of grains per spike; cross No.4 for number of spikes/plant; crosses No.3, No.12 and No.10 for grain yield per plant, therefore, it might be decided that these crosses may be beneficial for enhancing wheat grain-yield programs under low or high N conditions. The median grade of dominance was greater than one for all characters under both conditions, suggesting the importance of over dominance gene effects in the genetics of these traits. Heritability in broad sense (hb.s.) had high values for all traits under both conditions. Lower heritability estimates in narrow sense (h2n.s.) were detected for all the studied traits under both conditions, except each of spikes number /plant, weight of 100-grain and protein % at both conditions which had moderate values of narrow sense heritability, reflecting the part of environmental factors and dominance genes in heirloom scheme of these characters.

The paper presents the evaluation of the total combining ability of the seed parents of white sweet clover Melilotus albus and yellow sweet clover Melilotus officinalis based on leaf formation, forage productivity and seed productivity. The results of competitive heterosis for the yield of herbage, dry matter and seeds of the polycross offspring Syn1 are also presented. Among the polycross offspring Syn1 Melilotus albus, SGP-4-12507 and SGP-5-12508 were selected based on their leaf formation (50 and 50%, respectively); competitive heterosis was 16.3 and 22%, respectively. Based on the total combining ability of offspring Syn1 of Melilotus albus, the following biotypes were selected: SGP-2-12519 (27.1%) and SGP-1-12503 (20.8%) for forage productivity; SGP-4-12601 (14.7%) and SGP-5-12508 (13.0%) for dry matter productivity; SGP-4-12601 (50.4%), SGP-2-12519 (19.2%) and SGP-5-12508 (14.1%) for seed productivity. The highest total combining ability were found for the following biotypes of Melilotus officinalis: SGP-9-12454 and SGP-10-12455 for leaf formation (18.2 and 13.3%, respectively); SGP-10-12455 (12.5%) for herbage productivity; SGP-10-12455 (29.6%) and SGP-9-12454 (24.2%) for dry matter productivity; SGP-6-12520 (15.4%) and SGP-9-12454 (14.1%) for seed productivity. Selected sweet clover samples can be recommended as the best basic material for further work on selection for high forage and seed productivity.