Combining Ability for Growth, Yield and Related Traits In Cucumber (Cucumis Sativus L.) Under Subtropical Conditions of Garhwal Himalayas

To assess the combining ability for quantitative and qualitative traits in cucumber a full diallel set of 7 parents and their 42 F1’s was evaluated at Horticultural Research Centre, Department of Horticulture, H.N.B. Garhwal University, Srinagar (Garhwal), Uttarakhand, India during 2015 and 2016. The mean sum of squares due to general combining ability (GCA) was of significant differences at 1 % level for almost all the characters. The variance due to specific combining ability (SCA) was found highly significant at 1 % level for almost all the characters. Results from general combining ability studies revealed that the parent, New Manipur-1 showed significant GCA effect in desired direction for maximum characters viz., length of vine, days to first fruit harvest and number of fruits per vine. The cross combinations, Seven Star x New Manipur-1 for length of vine, Swarna Purna x Seven Star for days to first fruit harvest; K-90 x Seven Star for number of fruits per vine and the cross PB-Naveen x Swarna Purna for total fruit yield per vine showed significant SCA effect in desired direction and found to be superior specific cross combinations. Bangladesh J. Bot. 50(4): 1003-1010, 2021 (December)

Implementation of partial diallel analysis to determine general combining ability and agronomic character genetic parameters of shade-tolerant maize lines

Information about combining ability and genetic parameters guide maize breeders in selecting parents and gene action of the desired trait. This study aims to determine the general combining ability of the yield characters of shading tolerant maize lines and the genetic parameters of their agronomic characters. This research was conducted at IP2TP Bajeng in December 2020-March 2021. The study was arranged in a randomized block design with three replications. The genotypes used were nine hybrids obtain from a partial diallelic (2x6). The results showed that line SHD3 showed good general ability for yield. High heritability values were shown by variables days to anthesis, days to silk, plant height, ear height, leaf length, leaf width, 100 grains weight and ear diameter.

Assessment of combining ability in purple corn parents under line × tester mating design using GGE biplot

Mufidah N, Sugiharto AN, Waluyo B. 2021. Assessment of combining ability in purple corn parents under line × tester mating design using GGE biplot. Biodiversitas 22: 4545-4554. One strategy to increase corn quality is the development of new corn cultivars by incorporating the character of nutritional content. The study aims to obtain information on the combining ability of purple corn lines as well as determine the best parental lines for purple corn hybrid development using the GGE biplot approach. This study used 24 hybrids generated from crossings of 8 purple corn lines with 3 testers, which were crossed using a line × tester mating design. Plant performance was assessed using a randomized block design of three replications. The F-test was used to assess and test the experiment variance. The combining ability of purple corn lines was examined using the GGE biplot method. The result showed that the GGE biplot approach successfully identified the best combiner and combinations generated between purple corn lines and non-purple corn lines. Purple corn lines P1Y1 had the best general combining ability for fresh ear yield and total anthocyanin content, meanwhile, P1Y2 had the best general combining ability in most of the agronomic traits, namely ear diameter, shelled ear weight, number of grains row-1, and as well as total anthocyanin content. These 2 lines were also identified as the best parent chosen in the best combination in this study.

Breeding and genetic peculiarities of spring barley 1000 kernel weight under conditions of the central part of the Ukrainian Forest-Steppe

Purpose. To reveal the breeding and genetic peculiarities for spring barley 1000 kernel weight and to identify genetic sources for breeding under conditions of the central part of the Forest-Steppe of Ukraine. Methods. Investigations were carried out at the V. M. Remeslo Myronivka Institute of Wheat of the NAAS of Ukraine. Spring barley F1 of two comp­lete (6 ´ 6) diallel crossing schemes was investigated. The first scheme included modern both domestic and foreign spring barley malting varieties (‘MIP Tytul’, ‘Avhur’, ‘Datcha’, ‘Quench’, ‘Gladys’, ‘Beatrix’), the second – classic covered awned (‘MIP Myroslav’, ‘Sebastian’), awnless (‘Kozyr’, ‘Vitrazh’) and naked (‘Condor’, ‘CDC Rattan’) varieties. Results. Various types of inheritance of 1000 kernel weight were revealed, with the exception of negative dominance. The proportion of combinations with corresponding values ​​of the degree of phenotypic dominance varied depending on the genotypes involved in the crossing and the years of testing. In both crossing schemes, both in 2019 and in 2020, positive overdominance was found in most combinations. The grea­test number of combinations with the manifestation of hete­rosis under different growing conditions was noted when varieties ‘Gladys’ and ‘MIP Myroslav’ were used in crossing. According to the parameters of genetic variation, it was revealed that the trait was determined mainly by the additive-dominant system. The dominance was aimed at increasing the 1000 kernel weight. Only in the second crossing scheme in 2019 the value of the directional dominance indicator was unreliable. In the loci, incomplete dominance in 2019 and over-dominance in 2020 were revealed. Reliably high effects of the general combining ability in both years were noted for varieties ‘Datcha’, ‘Gladys’, ‘MIP Myroslav’, ‘Kozyr’ and ‘Vitrazh’. Conclusions. The revealed breeding and genetic peculiarities indicate that for the overwhelming majority of created hybrid combinations will be required the final selection in later generations, when the dominant alleles are homozygous. Spring barley awned varieties ‘Gladys’, ‘MIP Myroslav’ and ‘Datcha’, as well as awnless varieties ‘Kozyr’ and ‘Vitrage’ can be used as effective genetic sources for increa­sing the 1000 kernel weight

Heterosis, Combining Ability, Genetic Diversity and their Interrelationship in Pigeonpea [Cajanus cajan (L.) Millspaugh]

Background: The development of superior hybrids is must to break the existing yield plateau ( less than 800 kg/ha) in pigeonpea and hence, the genetic mechanism governing the heterosis in pigeonpea must be decoded. Methods: The present study was laid down using randomized block design during kharif 2018-19 at GBPUAT, Pantnagar with 36 genotypes (8 parents and 28 F1 hybrids) of pigeonpea. The estimates of combining ability were evaluated by using the Griffing’s, Method II, Model I. The observations recorded for yield and related traits were subjected to the estimation of genetic diversity (GD) using the D2 statistics. The correlation between heterosis and different parameters viz., parental mean (PM), specific combining ability (SCA), mean of general combining ability (MGCA) and genetic diversity (GD) were estimated by using Pearson’s correlation. Result: High estimates of SCA variance and more than unity ( greater than 1) average degree of dominance for all the characters indicated the presence of over dominance. The SCA followed by MGCA were found to be most reliable parameters to predict the heterosis. The parents having high x low or high x high per se performance, good x poor GCA effects and with medium genetic diversity resulted in high frequency of heterotic hybrids.

Half Diallel Analysis for Biochemical and Morphological Traits in Cultivated Eggplants (Solanum melongena L.)

Eleven morphologically diverse cultivated eggplant accessions were used for hybridization following half diallel mating design to obtain 55 hybrids. Evaluation of hybrids along with the parents was conducted over two locations followed by randomised complete block design with three replications to study gene action and combining ability of 15 morphological and biochemical traits. The analysis of variance indicated highly significant differences among the environments and interaction of genotype and environment, except for fruit length to width ratio. Additive gene effects were significant for the inheritance of these traits and expression of these additive genes were greatly affected by environments. The general combining ability (GCA) was greater than their respective specific combining ability (SCA) for all traits except for fruit yield per plant. High values of GCA and SCA effects for characters of interest were dispersed among different genotypes. From this study it was observed that the best parental line was BT15 based on days to first flowering, total number of fruits per plant, total soluble solids and total phenol content. Besides, the parent BM5 showed good general combining ability effects for fruit yield per plant, fruit length and fruit length to width ratio and the parent BB1 performed good general combining ability for fruit diameter, fruit girth and fruit weight. Besides, other parents showed the best performance for only one trait. On the other hand, the hybrid BT6 × BT15 was reported bearing early flowering with high total phenol content and the hybrid BM9 × BB26 has high fruit yield with high soluble solids. Besides, the hybrid BM9 × BB1 has a high fruit diameter and fruit weight. All other hybrids except for these three (BT6 × BT15, BM9 × BB26 and BM9 × BB1) were shown the best performance for only one trait. Hence, based on the desired trait, the hybrid can be selected for future use after large scale evaluation.

Estimation of general combining ability (GCA) in fifteen Cucumis sativus L inbred lines of the fifth generations

The study on General Combining ability (GCA) of 15 cucumber inbred lines (I5) was carried out at the Research and Development Center for High-tech Agriculture, Ho Chi Minh City. The objective of the study was to identify the appropriate parental lines for producing F1 hybrid cucumber cultivars. Experimental materials included 15 cucumber inbred lines (I5) (L3, L9, L21, L22, L28, L32, L33, L36, L39, L61, L63, L69, L71, L74 and L78) and two test lines (T1 - TN 456 from Trang Nong Company, imported from Thailand and T2 - Cuct 1450 from Chia Tai - Thailand), forming 30 hybrid combinations by the method of topcross. The results showed that seven inbred lines including L3, L9, L21, L28, L33, L61 and L71 had high ability to combine with both T1 and T2 tester lines abby fruit yield with GCA index from + (0.8) to + (9.4). Evaluation of 30 cucumber hybrid was combinations on the growth and fruit yield characteristics showed that L28/T1 and L71/T2 hybrids were significantly different from other hybrids with high yields of 43.1 tons/ha and 41.3 tons/ha, respectively

Daya gabung dan aksi gen komponen hasil jagung profilik hasil tinggi menggunakan analisis line X tester

Peningkatan produktivitas jagung dapat dilakukan melalui perakitan varietas jagung yang memiliki tingkat prolifikasi tinggi. Ketersediaan galur-galur yang memiliki tingkat prolifikasi tinggi dan daya gabung yang baik akan memberikan peluang besar dalam perakitan jagung hibrida prolifik dengan hasil tinggi. Penelitian ini bertujuan memilih galur-galur prolifik yang memiliki daya gabung yang baik pada karakter prolifikasi dan mengevaluasi tingkat prolifikasi dan produktivitas jagung hibrida yang dibentuk dari galur-galur tersebut serta mengetahui aksi gen yang berperan pada karakter komponen hasil. Percobaan dilakukan dua tahap yaitu pembentukan hibrida dari galur-galur prolifik dengan metode testcross dan evaluasi hibrida yang terbentuk dengan menggunakan rancangan alfa lattice dengan tiga ulangan. Hasil penelitian menunjukkan galur G7 memiliki nilai daya gabung umum yang baik untuk karakter persentase tanaman prolifik. Hibrida G35/G102612 merupakan hibrida uji dengan persentase tanaman prolifik tertinggi 55,8%. Hibrida G7/Mal03 dengan hasil biji 12,9 t ha-1 dan persentase tanaman prolifik 53,9% merupakan jagung hibrida prolifik dengan hasil tinggi. Aksi gen non aditif lebih berperan dalam penampilan karakter komponen hasil pada jagung prolifik.AbstractMaize productivity can be increased by improving maize varieties with high prolificacy. The adequate of high prolificacy lines with a good combining ability will provide great opportunities to form a high yield prolific maize. The research aimed to select the prolific line which has good combining ability on the prolificacy and evaluate the prolificacy and productivity of the hybrid maize from these lines and to know the gene action which plays role in the yield component characters. The research was carried out in two stages, i.e. the formation of hybrids from the prolific line using the testcross method and evaluation of hybrids using the alpha lattice design with three replications. The results showed that line G7 had a good general combining ability for the percentage of prolific plants. Hybrid G35/G102612 was the test hybrid with the highest percentage of prolific plants of 55,8%. Hybrid G7/ Mal03 which had the yield of 12,9 t ha-1and percentage of prolific plants 53,9% was the prolific hybrid maize with the high yield. The non-additive effect played the main role for yield component characters of prolific hybrid maize.

Diallel analysis of the duration of vegetation period in tomato (Solanum lycopersicum L.) with increased lycopene content in the fruit

<p> Five parental forms of tomato (Solanum lycopersicum L.) and twenty hybrids F1, were studied which were obtained by the complete diallel scheme (5 x 5). For genetic analysis (by Hayman, 1954; Jinks,1954) was used line №477 (sp,u), variety Alya (sp) with reduced duration of vegetation period and three collection samples with the high lycopene content in fruits: Dark Green (hp-2dg), МО 112 (hp), Т˗3627 (Bc). The effects of the general (GCA) and specific combining ability (SCA) of the duration of vegetation period were determined and established character of inheritance. According to the results of research, the duration of vegetation period is controlled by additive-dominant genetic system. Inheritance occurs by type of over dominance, and in dry and hot summers which led to the prolongation of the duration of vegetation period, there is a tendency to incomplete dominance, but it is apocryphal. In genetic control a major role play non-additive effects of genes. The best reliable effects of the general combining ability (GCA) had line №477 and variety Alya. They can be recommended for the creation of heterotic hybrids and varieties.</p>