Top Crosses Research Articles

Study on the tunable band gap of LiNaPb2Br6 superlattice and its optical properties

The property changes between APbBr3 (A = Li, Na) and LiPbBr3/NaPbBr3 superlattice (LiNaPb2Br6), as well as the electronic structure and optical properties of LiNaPb2Br6 under various pressures, have been investigated using the GGA-PBE method based on first-principles. The research shows that the band gap (Eg) value of LiNaPb2Br6 is 1.674 eV at 0 GPa, which is between that of LiPbBr3 and NaPbBr3. Meanwhile, the results indicate that the Eg of LiNaPb2Br6 gradually decreases with the increase in pressure, reaching 0.080 eV at 7 GPa, and its valence band top crosses the Fermi level at 8 GPa. Therefore, by combining the construction of superlattices with the application of pressure, the Eg of LiNaPb2Br6 can be continuously regulated in the range of 0–1.674 eV. Since the optical properties of a material primarily depend on its band structure, the optical properties of LiNaPb2Br6 can be widely adjusted by continuously tuning the Eg of this superlattice. The calculated results demonstrate that the optical properties of LiNaPb2Br6 were optimized in comparison to APbBr3 (A = Li, Na). In addition, the increase in pressure improves the absorption capability of LiNaPb2Br6 in both the visible and ultraviolet regions, thereby expanding the potential applications of LiNaPb2Br6 in the optical field.

RECURRENT SELECTION FOR GENERAL AND SPECIFIC COMBINING ABILITY IN MAIZE

This study was aimed to identify efficiency of recurrent selection program to improve maize population. This program was applied to var. Buhooth 106 with var. 5012 Using RGCA with the inbred Zm7 for the production of RSCA. The recurrent selection program was implemented for four consecutive seasons (2020 - 2021) at the Fields Station of the College of Agriculture - University of Anbar. In the spring season 2020, 100 top crosses were obtained from both varieties and progeny. During the fall season 2020, an experiment was carried out to compare the top crosses of each variety RGCA and RSCA using a 10 × 10 partially balanced lattice design.. Six genotypes from each genetic population as well as Buhooth 106 and 5012 and Zm7 inbreds). The genotype-S1-2 RSCA achieved the lowest female flowering period for females 61.50 days, the highest number of rows per ear 17.80 rows, and the highest grain yield 177.82 g. The genotype-S1-3 RSCA achieved the highest leaf area 0.593 m2 and the highest number of kernels per row 43.11 kernel. The broad sense heritability of the traits of the number of rows and the number of kernels in the row and the yield of the plant reached 53.23%, 73.85% and 41.94%, respectively, and high genetic advance for kernels per row and grain yield of 4.79 and 15.52 respectively.

Performance and Genetical Analysis of Some New Top Crosses Of Maize under Normal Irrigation and Drought Stress Conditions

Performance and Genetical Analysis of Some New Top Crosses Of Maize under Normal Irrigation and Drought Stress Conditions

The adaptation top crosses of anthocyanins corn in lowland zone of Palu Indonesia

Anthocyanins corn held to increase of human health, the color of seeds was orange to black. The experiment was to studied characters of some families as top crosses anthocyanins corn under interaction genotypes (G), and season (S) in valley of Palu in Indonesia. The experiment was conducted by randomized complete block design with three replications in experimental farm of Sidondo under two season rainy and dry condition. There are ten top crosses populations as anthocyanins corn as candidate included check to evaluated on 2017. The objective of experiment was to study of characters and to find of which is genotypes was stable and high yield to promoting as candidate for F1 top crosses varieties. Interaction data between genotype (G) and season (S) were analyzed manually. The result show that there are significant interaction GxS and founded the genotypes would be promising as new F1 candidate was PMU(S1) Synt. F. C1-2-3xtester: PPH(S1) C2. The potential would be founded 6.0 - 7.0 t/ha, characters of candidate was scored one of plant aspect, position of ear height is middle of plant height, and there are 45 days for anthesis. The released top crosses of anthocyanin corn would be develop under poor farmers for aims to increase income, health and anticipated of mall nutrition.

Comparative Assessment of Genetic Variability Realised in Doubled Haploids Induced from F1 and F2 Plants for Response to Fusarium Stalk Rot and Yield Traits in Maize (Zea mays L.)

Doubled-haploid lines (DHs) are normally produced from F1 plants in maize (Zea mays L.). Several studies have found a low frequency of recombinants in doubled haploids produced from F1 plants that could limit the selection response. Hence, an attempt was made to produce doubled haploids from the F2 generation to verify whether one more round of meiotic recombination could lead to increased genetic variability and assess the response to selection. The F1 and F2 plants of two cross-combinations, VL1043 × CM212 and VL121096 × CM202, were subjected to doubled-haploid production and evaluated in terms of their reaction to Fusarium stalk rot and yield traits along with F2 individuals of the same two crosses. There was significant variation in the number of DHs produced when F1 and F2 plants were subjected to DH production in the cross VL121096 × CM202. Furthermore, substantial genetic variability was observed among the DHs produced from the F1 generation (DHF1s), F2 generation (DHF2s), and F2s for Fusarium stalk rot (FSR) resistance. The genetic variance was more extensive in DHF2 compared to DHF1 plants in the cross VL1043 × CM212. Extreme candidate plants (highly resistant, resistant, and highly susceptible) were found in the F2 generation with a more standardized range than in the DHs. In the DH populations, the close correspondence between the phenotypic coefficient of variability (PCV) and the genotypic coefficient of variability (GCV) indicated less influence from the environment compared to the F2 plants. The heritability estimates in the DHs were greater than in the F2 plants of the VL1043 × CM212 cross, while in the VL121096 × CM202 cross, the heritability was almost the same between the DHs and F2 plants due to the relatively small population size of the DHs. The positively skewed leptokurtic distribution of the DH populations indicated the role of fewer genes, with the majority of them exhibiting complementary epistasis with decreasing effects in response to FSR. The mean estimated yield and genotypic variance in the top crosses produced from randomly chosen DHF1 and DHF2 plants of the cross VL1043 × CM212 were similar in magnitude.

Genetic Analysis of Morpho-metric Traits and Correlations of Yield Parameters in Soybean (Glycine max L. Merr)

Top crosses comprising 2 testers and 8 lines were made in the screen house using Line × Tester model. Observations were made on days to flowering, pod maturity, harvest, pods per plant, branching pattern, seeds per pod, 100 seed weight and yield/ha; crude protein, crude fiber, carbohydrate, moisture, ash and oil, as well as trypsin, tannins and phytate. Data collected were subjected to Analysis of Variance and the means separated using Duncan Multiple Range Test (DMRT), at 5% probability level. Genetic component analysis was carried out on the traits using Analysis of Genetic Design (AGD-R) package, to determine heritability, General Combining Ability (GCA) and Specific Combining Abilities (SCA). Results of the study revealed that, positive GCA values were recorded by TGM954 (0.01), TGM120 (0.07), TGM553 (0.70), TGM555 (0.58), TGM574 (0.19), TGM584 (0.14) and TGX1904-6F (0.12) for 100 seed weight; TGM954 (76.83) and TGM584 (12.54) for seed yield. Generally, TGM954 was a better general combiner than TGM951, because it combined well with other varieties for yield and yield-related traits. High heritability estimates were recorded for 100 seed weight (84.10%), number of branches (86.61%), days to flowering (91.69%), pods per pod (88.48%) and seed yield (86.07%). It can be concluded, that, crosses using Line × Tester model is encouraged for trait transfer and enhancement of soybean seed yield.

Identification of New Sources for Earliness and Low Grain Moisture at Harvest through Maize Landraces’ Test-Cross Performance

Early maturity is a highly important factor in the interrelations between yield, grain moisture, and plant density, contributing to cost-efficient maize production. Landraces conserved in gene banks present a promising basis for enriching the diversity of early maize breeding material. To start and speed up the mobilization of the maize genetic resources maintained in the ex situ Maize Research Institute Zemun Polje gene bank collection, which are currently scattered, little studied, and underused, 63 landraces were selected as new potential sources of early maturity; their test-cross performance with two divergent early testers was evaluated. The majority of the landraces with a prevailed flint type (29) exhibited heterosis for yield when crossed with the Iowa Stiff Stalk Synthetic—Iowa Dent tester (102NS), out of which 20 top crosses expressed grain moisture below the defined threshold value (21.1%). The best performing landraces can be used as a starting point for a new pre-breeding programme for the broadening of flint maize breeding material. In parallel, nine landraces expressed simultaneous heterosis when crossed with the flint tester (14NS), exhibiting grain moisture above the threshold value. A simultaneous heterotic effect with two divergent inbred testers implies the existence of an independent heterotic pool. These findings will contribute to the broadening of maize breeding material for early maturity and low grain moisture at harvest, which are important goals in maize breeding.

Comparative performance of top cross and population cross hybrids in white Maize using a common tester

Improved maize populations and cross hybrids can be beneficial alternatives for commercial single-cross hybrids and good elite sources for diverse inbred lines. A set of 22 genotypes comprised 10 population crosses, 10 top crosses, and two check cultivars were evaluated at Cereal Crop Research Institute, Pirsabak-Nowshera, in a randomized complete block design with three replicates in 2014. This research's major aims were to determine the magnitude of heterosis and the degree of character association between yield and its attributes to select superior genotypes from the breeding material. Data were recorded on maturity, and yield associated traits, where significant genetic variability was observed among the genotypes for all the studied traits except days to silking. Mean values for the studied traits ranged from 44 to 52 days for tasseling, 48 to 54 days for anthesis, 49 to 54 days for silking, -1.33 to 2.33 for the anthesis-silking interval, 2.53 to 8.47 kg for fresh ear weight, 12 to 16 rows for kernel rows cob-1, 27.15 to 37.49 g for 100-kernel weight and 2830 to 7649 kg ha-1 for grain yield. Days to silking, anthesis silking interval, and kernel rows cob-1 showed low broad sense heritability (12.08%, 24.84%, 27.59%), days to tasseling, days to anthesis revealed moderate heritability (40.53%, 36.62%), while fresh ear, 100-kernel weight, and grain yield exhibited high broad-sense heritability (94.89%, 82.33%, 90%). Negative and significant heterotic values were observed for maturity traits, while heterotic values were positive and significant for yield-associated traits. Correlation analysis revealed that characters like fresh ear weight (r = 0.93) and 100-kernel weight (r = 0.50) manifested a strong positive and significant association with grain yield. Based on mean performance and grain yield, promising hybrids were 3008F3 x 2007-WC and 3008F3 x 2010. The current study revealed significant genetic variability among the tested hybrids; hence, it can be used in future breeding programs to produce early maturing and high-yielding maize hybrids.Days to tasseling, genetic variability, heterosis, population cross, top cross Keywords: HBV, HCV, ICT, PCR, Risk factors, Mansehra

Canonical interrelationships in morphological characters, yield and nutritional components of corn

The increase in the world population, the need to increase food production, both in quantity and quality, becomes increasingly prominent. The objective of this work was to identify the canonical correlations between yield components, morphological characters, micronutrients, bioactive compounds and amino acids in corn. The experimental design used was a randomized block containing 11 treatments arranged in three replications. The treatments consisted of 11 Top Crosses hybrid genotypes, these being made through crosses directed between a narrow genetic base tester hybrid for specific combining ability with 11 S5 inbred lines. It is inferred that groups considered yield components, secondary traits, bioactive compounds, micronutrients and amino acids are dependent. Promising characters are identified for the corn breeding for high yields, nutritional and energetic quality of corn grains. The indirect selection of grains with additions in essential amino acids can be directed to plants with superiority in height, mass and width of grains, phenols, flavonoids, soluble solids and zinc content.

Studies on variability, heritability, genetic advance and transgressive segregating in brinjal (Solanum melongena L.)

Significant variability is available in the F2 population of brinjal. Top crosses of brinjal Biliudda badane × mullu badane produced from F1 generation were in augmented design at ZARS Shimogga in Kharif 2017. They have several characteristics of plant breeding significance with sufficient scope for added improvement to growing conditions. The F2 study showed significant variation for nine quantitative traits. Close estimates between GCV and PCV values indicated lesser influence of environmental factors on the expression of traits under study. In this investigation, the proportion of genetic contribution of high GCV, PCV coupled with high broad sense heritability and genetic advance to the overall phenotypic expression of the studied traits like number of fruits per plant, number primary branches, number of flowers per plant was high, indicating predominant control of additive genes, and these traits could be improved upon by selection without progeny testing. High magnitude of heritability for most of the characters suggested the progress of improvement in yield and its components. Differences in mean values of parents for various characters indicated involvement of diverse parents in the crosses studied. The F2 plants exceeded either of the parents for most of the characters, which seems to be due to transgressive segregation.

Evaluation and Classification of Yellow Maize Inbred Lines Using Line X Tester Analysis Across Two Locations

Ten yellow maize inbred lines and three testers were top crossed in line × tester scheme in 2019 season. The resulted 30 top crosses with two check hybrids were evaluated at two locations in 2020 growing season to assess mean performance, general and specific combining ability and their interaction with locations as well as elucidate type of gene action. The recorded data were days to 50% silking, plant height, ear height, ear length, ear diameter, No. of rows/ear, No. of kernels/row and grain yield (ardab/fed). The results showed that, the mean squares due to locations (Loc), genotypes (G), crosses (Cr.), G × Loc and Cr. × Loc interactions were significant for all the studied traits. Highly significant differences were observed among the evaluated lines (L), testers (T) and its corresponding hybrids for all traits. non-additive gene action gave an important role in the inheritance of all the studied traits. The inbred lines L2, L4 and L6 showed the best desirable GCA effects for earliness, L6, L7 and L10 for shortness and L4, L5, L6, L7 and L9 for lower ear placement. Whereas the inbreeds L3, L6 and L7 were the best general combiners for grain yield. The crosses L2×T1, L8×T1, L1×T2, L7×T2, L3×T3, L6×T3 and L10×T3 had the best SCA effects for grain yield. The ten inbred lines were classified into three different heterotic groups using HSGCA method. These groups could be used for selecting the best parents for making crosses in maize breeding programs.

Combining ability and gene action for sexual compatibility and pattern of nut colour segregation among ten elite clones of kola (Cola nitida (Vent) Schott and Endl.)

Knowledge of combining ability and mode of inheritance is important in devising strategies to breed compatible and high yielding plant varieties. This study determined combining ability and understood the mode of inheritance of sexual compatibility in Cola nitida, a crop in which incompatibility was reported. 10 × 10 complete diallel mating design was used to cross ten (10) elite clones of kola. Data collected included percentage pod set and nut traits of the various crosses. Percentage pod set differed significantly among crosses (p 80% pod set) as compared to crosses between red and pink colour nut genotypes. Both additive and non-additive gene effects were significant (p < 0.001) for sexual compatibility in kola. However, the non-additive genetic variance was larger than the additive genetic variance for this trait. GCA estimates for genotypes A1 and JB1 were significant and positive for sexual compatibility. These genotypes are considered excellent combiners for sexual compatibility or pod set and could be used as pollinizers or pollen donors in kola orchards. Top crosses exhibiting highly significant and positive SCA for sexual compatibility included JB27×JB32, JB19×JB32, JB35×JB19, A1×JB34, JB35×A12 (direct crosses) and JB1×JB27, A1×JB35, A12×JB19, A1×A8, A1×JB35 (reciprocal crosses). The narrow and broad sense heritability estimated for pod set were 0.17 and 0.57, respectively. The correlation coefficients between pod set and the number of nuts per pod, pod weight and nut weight were significant (p < 0.05) and positive. Although, the red nut colour is dominant over white and pink nut colours, it was fewer for some crosses compared to the number of white and pink nuts. This indicated the potential involvement of epigenetic factors in the inheritance of nut colour in kola.

Genetic analysis for some top crosses of yellow maize

Twenty elite yellow maize inbred lines were crossed as female parents with three different testers as male parents, i.e. Gem. Pop. (Broad genetic base), Single cross 101(Narrow genetic base) and Inbred line 100 (Narrow genetic base) at the Experiment Research Station of Moshtohor, Benha University, Egypt during 2014 growing summer season. The resulting 60 crosses with three commercial check hybrids i.e. SC 155, SC Pioneer 3080 and TWC 352 were evaluated in a yield trial in two sowing dates during 2015 growing summer season. The results showed that, sowing dates, crosses, lines, testers and line x testers mean squares were significant for all traits. The seven parental inbred lines (L-4, L-5, L-10, L-12, L-13, L-14 and L-19) possessed high GCA effects for grain yield and six lines (L-1, L-7, L-10, L-13, L-16 and L-18) possessed high GCA effects for earliness. These lines can be utilized as promising inbred lines in a hybridization program to develop high yielding and early maturity maize hybrids. The seven crosses (T-1 × L-7, T-1 × L-13, T-1 × L-17, T-2 × L-4, T-2 × L-5, T-2 × L-10 and T-2 × L-12) which had out-yielded significantly the best check SC. 3080 could be utilized for future breeding work as well as for direct release after confirming the stability of their performances observed in the current study. Hence, the information from this study may possibly be useful for researchers who would like to develop high yielding hybrids of maize.

STUDIES ON THE GENETICAL COMPONENTS USING THE TOP CROSS MATING DESIGN IN MAIZE (Zea mays L.)

The field experiments were carried out in two successive summer seasons 2014 and 2015 at the experimental farm of the Faculty of Agriculture, Menoufia University, in El-Raheb, Egypt to evaluate yellow inbreed lines of maize through line x tester analysis. A total of twenty-five (Zea mays L.) yellow S4 lines were used to establish the experiment materials. Two testers of yellow maize were used in this investigation to make all possible line x tester crosses. The two testers used in this study were Giza 658 and Sids 3120. Two check verities were used in this investigation their names are single cross Giza 168 and Giza 176. The most important results For grain yield (ard/fed), twelve, four and eight top crosses gave higher grain yield compared with the highest check Giza 168 under HD, ND and combined data, respectively. The top crosses L3 x T1 and L3 x T2 were the highest values for grain yield under this study. Therefore, the inbred line L3 was useful in maize breeding programs. The inbred lines L3, L4, L9, L11 and L14 desirable significant GCA effects for grain yield (ard/fed). Thirteen top crosses showed significant positive SCA effects for grain yield (ard/fed) under HD, ND and their combined. Also, the top crosses L1 x T2 and L11 x T2 were significant under high plant density. The top cross L3 x T1 was the higher value of heterosis relative to two check varieties for grain weight per ear weight and grain yield. Also, eight top crosses were highly significant heterosis relative to two check varieties for grain yield (ard/fed).

STUDIES ON THE GENETICAL COMPONENTS USING THE TOP CROSS MATING DESIGN IN MAIZE (Zea mays L.)

The field experiments were carried out in two successive summer seasons 2014 and 2015 at the experimental farm of the Faculty of Agriculture, Menoufia University, in El-Raheb, Egypt to evaluate yellow inbreed lines of maize through line x tester analysis. A total of twenty-five (Zea mays L.) yellow S4 lines were used to establish the experiment materials. Two testers of yellow maize were used in this investigation to make all possible line x tester crosses. The two testers used in this study were Giza 658 and Sids 3120. Two check verities were used in this investigation their names are single cross Giza 168 and Giza 176. The most important results For grain yield (ard/fed), twelve, four and eight top crosses gave higher grain yield compared with the highest check Giza 168 under HD, ND and combined data, respectively. The top crosses L3 x T1 and L3 x T2 were the highest values for grain yield under this study. Therefore, the inbred line L3 was useful in maize breeding programs. The inbred lines L3, L4, L9, L11 and L14 desirable significant GCA effects for grain yield (ard/fed). Thirteen top crosses showed significant positive SCA effects for grain yield (ard/fed) under HD, ND and their combined. Also, the top crosses L1 x T2 and L11 x T2 were significant under high plant density. The top cross L3 x T1 was the higher value of heterosis relative to two check varieties for grain weight per ear weight and grain yield. Also, eight top crosses were highly significant heterosis relative to two check varieties for grain yield (ard/fed).

Efficiencies of Heterotic Grouping Methods for Classifying Early Maturing Maize Inbred Lines

The success of a hybrid breeding program is dependent on available heterotic patterns for exploitation of grain-yield heterosis. The efficiency of the assignment of germplasm lines into heterotic groups is a prerequisite for obtaining useful heterotic patterns among germplasm lines. A total of 256 maize hybrids, comprising 244 top crosses, six diallel cross hybrids, and six checks, were grown under Striga infestation, drought, and optimal conditions, from 2015 to 2017. The study determined the combining abilities of the parental inbreds, classified the inbreds into heterotic groups, and compared the efficiencies of the following four grouping methods for classifying the inbreds: specific combining ability (SCA) effect of grain yield; general combining ability (GCA) effects of multiple traits (HGCAMT); SCA and GCA (HSGCA) for yield; and single nucleotide polymorphism-based genetic distance (SNP-based genetic distance (GD)). Significant GCA and/or SCA mean squares were revealed for most measured traits in all test environments. Sums of squares (SS) due to GCA were higher than SCA SS for measured traits in all test environments. The HSGCA, SCA, and SNP-based GD methods identified four heterotic groups, whereas the HGCAMT identified three groups, in all environments. The additive gene effect was preponderant in the inheritance of most measured traits. The efficiencies of the grouping methods varied with the test environments. The HSGCA and SCA methods were the most efficient for grouping in all test conditions. For practical breeding purposes, the HGCAMT and HSGCA methods were recommended under Striga infestation and drought, respectively. The heterotic patterns, which were revealed in this study, were effective for planning hybridization schemes for developing high-yielding, Striga-tolerant/resistant, and drought-tolerant maize hybrids for stressful environments.

Combining Abilities for Yield and Its Components through Line by Tester Analysis in Maize under Two Plant Densities

The field experiments were carried out in two successive summer seasons of 2014 and 2015 at the experimental farmof the Faculty of Agriculture, Menoufia University, in El-Raheb, Egypt to evaluate yellow inbreed lines of maize throughline x tester analysis.Top crosses were made each of the twenty-five S4 lines and the two testers by hand to give a total of 50 top crosses in2014season. In the second season (2015) two adjacent experiments were conducted under two plant densities. The firstexperimental represented a normal plant density (ND) of 24000 plant/fad., (hills spaced 25 cm apart and one plant/ hill).The second experimental represented plant density (HD) of 30000 plants/fad. (hills spaced 20 cm a part and one planthill). In each experiment the 50 top crosses as well as the two checks hybrids Giza 168 and Giza 176 were grown in aRandomized Complete Block Design with three replications. Performance of inbred lines varied with plant densities.Parental lines L3, L4, L5, L14 and L23 were the best in mean performance and general combining ability effects underthis study. Results indicated that σ² SCA was more important than σ² GCA for all studied traits, plant height at thecombined analysis. Non-additive gene action was more affected by the interaction with environments than the additiveeffects. The top crosses L12 x T2 and L17 x T2 showed desirable significant SCA effects for shortness and the low earplacement under low plant density. Thirteen top crosses showed significant positive SCA effects for grain yield (ard/fad)under HD, LD and combined analysis. Also, the top crosses L1 x T2 and L11 x T2 were significant under high plantdensity. The top crosses (L3 x T1 and L14 x T2) and (L3 x T2) showed significant number of ears per plot and 100-kernelweight relative to two check varieties for the top cross L3 x T1 gave the higher value of heterosis relative to the twochecks for ear weight and grain yield.

COMBINING ABILITY OF NEWLY DEVELOPED WHITE MAIZE (Zea mays L.) INBRED LINES VIA TOP CROSS ANALYSIS

Twelve newly developed white maize inbred lines were crossed with two testers i.e. SC 128 and SC 131 at Ismailia Agricultural Research Station during 2017 season. In 2018 summer season, the 24 top crosses and two white commercial check hybrids; TWC 321 and TWC 324 were evaluated under two locations (Loc); Ismailia and Mallawy Agricultural Research Stations. The studied traits were number of days to 50% silking (DS), plant height (PH), ear height (EH), ear length (EL), ear diameter (ED), number of rows/ear (RE), number of kernels/row (KR) and grain yield (GY). Mean square due to locations were significant for DS, EL, KR and GY traits. The crosses were significant for all studied traits, except PH trait. Mean square due to lines were highly significant for all traits except PH, EH, and KR. Mean square due to testers were highly significant for EH and GY. Also, mean square attributed to lines x testers interaction were highly significant for all traits except for DS, PH, and RE. The interactions of locations (Loc) with crosses and Loc x lines were highly significant for the studied traits except for PH. The superior inbred line Ism 6007 had desirable general combining ability (GCA) effects for grain yield and yield components. Also, the inbred line Ism 7100 showed better GCA effects for PH, EH, ED, RE and GY traits and inbred line Ism 7094 for earliness and grain yield. The tester SC 128 showed the highest GCA effect for grain yield. The best crosses for specific combining ability (SCA) effects were Ism 6040 x SC 128, Ism 7094 x SC 128, Ism 7169 x SC 128, Ism 7186 x SC 131 and Ism 7259 x SC 131 for grain yield and cross Ism 6007 x SC 131 for earliness, grain yield, and yield components. The non-additive gene effects were more important in controlling all studied traits. Moreover, non-additive gene effects were more interacted by environmental conditions than additive gene effects for all studied traits. The highest mean values and significant of crosses for grain yield (GY) were obtained from the Ism 6040 x SC 128 (37.5 ard/fad.), Ism 6007 x SC 131 (37.0 ard/fad.), Ism 7169 x SC 128 (36.7 ard/fad.), and Ism 7094 x SC 128 (35.5 ard/fad.). These three ways crosses out yielding significant than the commercial hybrids TWC 321 (33.7 ard/fad.) and TWC 324 (32.5 ard/fed). These promising hybrids should be tested in advanced trails.

Evaluation of new yellow maize (Zea mays) inbred lines using line × tester analysis

This study evaluated 20 elite yellow maize (Zea mays L.) inbred lines which were crossed as female parents with three different testers as male parents, i.e. Gem. Pop. (Broad genetic base), Single cross 101 and Inbred line 100 represent (Narrow genetic base) at the Experiment Research Station of Moshtohor, Benha University, Egypt during 2014 summer. The resulting 60 top crosses with three commercial check hybrids i.e. SC.155, SC. Pioneer 3080 and TWC.352 were evaluated in a yield trail in two sowing dates during 2015 growing summer season. A randomized complete block design (RCBD) with three replications was used. The data were recorded on days to anthesis (AD), maturity date (MD), leaf area of upper ear (LA), ear length (EL) and grain yield per feddan (GYPF). The results showed that, sowing dates, crosses, lines, testers except for (MD) and line × testers mean squares were significant for all traits. The parental inbred lines (L-4, L-5, L-10, L-12, L-13, L-14 and L-19) possessed high GCA effects for grain yield and (L-6, L-7, L-10 and L-11) possessed high GCA effects for earliness. These lines could be utilized as promising inbred lines in a hybridization programme to develop high yielding and early maturity maize hybrids. The seven crosses (T-1×L-7, T-1×L-13, T-1×L-17, T-2×L-4, T-2×L-5, T-2×L-10 and T-2× L-12) which had out-yielded significantly the best check SC.3080 could be utilized for future breeding work as well as for direct release after confirming the stability of their performances observed in the current study.

Mean Performance, Type of Gene Action, Combining Ability and Superiority Percentage of some New White Maize Inbred Lines in Top Crosses

Mean Performance, Type of Gene Action, Combining Ability and Superiority Percentage of some New White Maize Inbred Lines in Top Crosses