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The present study was aimed to identify potential Yellow Mosaic Virus (YMV) resistant donors and YMV linked markers for easy and efficient screening of germplasm. Forty - six blackgram genotypes were screened for Yellow Mosaic Virus (YMV) tolerance and yield traits under natural field conditions during summer, 2020 at Dryland farm, S.V.Agricultural College, Tirupati along with molecular validation with 15 SSR (Simple Sequence Repeats) markers associated with YMV tolerance. The genotypes viz., LBG-884, LBG-946, TBG-141, TBG-129, TBG-138, TBG-139, TBG-130 and GBG-1 displayed zero YMV incidence. TBG-104 and VBN-6 were identified as ideal cultivars for yield, earliness and YMV tolerance. The markers viz., CEDG 097, CEDG 180, CEDG 044, and CEDG 139 were adjudged as informative markers as evident indicated by their high PIC scores and Nei’s diversity index values. On scrutiny of the selection efficiency of all the alleles, CEDG 180 was found to be more efficient in differentiating resistant and susceptible genotypes. Visual comparison of trait profiles using genotype by trait (GT) biplot analysis identified the genotypes viz., TBG-104 and VBN-6 as ideal cultivars that serve as most desirable parents in breeding programs aimed at developing short duration, high-yielding varieties with YMV tolerance.

Understanding the genetic architecture of complex traits is the major thrust in plant breeding programs. Hence, the present investigation was carried out at a dry land farm of S.V. Agricultural College, Tirupati during rabi, 2020 to elucidate the gene action governing seed yield, yield related traits and earliness in blackgram. The experimental material consisted of six generations viz., P1, P2, F1, F2, B1 and B2 of five blackgram crosses viz., LBG-752 x TBG- 104, LBG-752 x PU-31, LBG-752 x TU-40, TU-40 x TBG-104 and IPU-2-43 x TBG-104. The scaling tests suggested that the simple additive–dominance model is inadequate in elucidating gene action in all the crosses for all the traits. Generation mean analysis based on six parameter model made evident that gene interactions varied cross-wise as well as character-wise. A complementary type of epistasis was observed for majority of the yield attributing traits, while days to 50 % flowering and days to maturity had duplicate epistasis in majority of the cross combinations. High yielding and short duration blackgram varieties could be developed by exploiting both additive and non-additive gene effects in the present set of breeding material through inter-mating of desirable transgressive segregants in the early generations followed by simple pedigree selection.

The present investigation was conducted in the F2 population of CR 1009 × WP 22-2 for earliness and semi-dwarfism. The yield contributing traits viz., plant height, days to fifty per cent flowering, number of productive tillers, panicle length, number of grains per panicle, thousand grain weight, grain length, grain breadth, length breadth ratio were interpreted based on their exposition of genetic variability, heritability and genetic advance besides correlation and path coefficient analysis. Negligible values of difference between PCV and GCV were recorded for plant height, number of grains per panicle, grain length and grain breadth suggesting lower environmental influence on the expression of these traits. The results of correlation and path analysis indicated that the number of productive tillers shows significantly positive and highest correlation with single plant yield pursuing selection of this trait is rewarding for grain yield improvement.

The present investigation was carried out to estimate the magnitude of heterosis over mid parent, better parent and standard checks (Tejaswini and Indam-5) for earliness, fruit yield and yield attributing traits in chilli (Capsicum annuum L.) and developed 54 F1 hybrids by crossing nine lines with six testers using line x tester mating design. The 71 genotypes (54 F1's hybrids along with their 15 parents and two standard checks) were evaluated in Randomized Block Design during kharif 2014 - 15 at HRS, Lam farm, Guntur. The analysis of variance for L x T revealed significant differences among the parents and crosses for all the 12 characters studied indicating the presence of wide range of variability among them. Among 54 F1 hybrids, twenty seven, seventeen, two and four hybrids exhibited significant positive heterosis for fruit yield per plant over mid parent, better parent, and standard checks - Tejaswini and Indam-5 respectively and the hybrid LCA 607 x LCA 703-2 registered significant standard positive heterosis (20.99 per cent) followed by LCA 655 x LCA 703-2 (15.09 per cent) over best check Tejaswini. Among the 54 hybrids, the hybrid LCA 355 x LCA 703-2 was found to be superior for plant height, LCA 504 x LCA 703-2 for plant spread, LCA 466 x LCA 678 & LCA 466 x LCA 315 for no. of primary branches per plant and LCA 442 X G4 for days to fruit maturity recorded maximum standard heterosis in desirable direction over best check Tejaswini, while the hybrid LCA 655 x G4 recorded maximum positive heterosis for no. of fruits per plant but inferior to best check Tejaswini. The hybrid LCA 446 x LCA 453 for days to 50 % flowering, LCA 355 x LCA 315 for fruit length, LCA 466 x LCA 453 for fruit diameter, LCA 607 x LCA 453 for average dry fruit weight, LCA 615 x G4 for no. of seeds per fruit and LCA 607 x LCA 705-2 for seed weight registered maximum standard heterosis in desirable direction over best check Indam-5. The identified heterotic hybrids could be further evaluated to exploit the heterosis or utilized in future breeding programmes to obtain desirable segregates for development of superior genotypes.

Combining ability analysis using eight parents and their 28 F1 crosses of bitter gourd obtained from diallel mating design (excluding reciprocals) for yield and earliness indicated that non-additive gene action played major role than additive gene action in inheritance of the traits. Among the parents, IC-04448, IC-470560, IC- 470558 and IC-085622 were found good general combiner for yield attributing characters and earliness hence, these parents can be exploited for hybridization for producing desirable recombinants in the segregating generations. High sca effects for yield and related characters were exhibited by IC-044438 × IC- 045339 followed by IC-044417 × IC-470558 and IC-045339 × IC-085622. For earliness the crosses viz., IC-044438 × IC-045339, IC-045339 × IC-470550 and IC-045339 × IC-470558 were identified as promising ones. Most good specific cross combinations involved High × Low and Low × Low general combiners. Five crosses were identified for developing high yielding genotypes of bitter gourd.

A field experiment was conducted to identify elite early maturing G. barbadense genotypes by evaluating morphological and fibre quality traits advanced genotypes developed at CICR, Regional Station, Coimbatore. Ten advanced genotypes of G. barbadense genotypes viz., CCB-5, CCB-11, CCB-17, CCB-26, CCB-27, CCB-28, CCB-29, CCB-30, CCB-33 and CCB-36 were used in this study. In the present study, analysis of variance of genotypes was highly significant for all the traits studied. Three genotypes viz,. CCB-29, CCB-36 and CCB-5 were found to be early maturing in terms of days to first flower, lower node no to first sympodial branch, boll formation in 90, 120 and 150 days after sowing and opening of bolls in 120 and 150 days after sowing. Regarding yield traits, maximum number of bolls per plant and higher seed cotton yield were recorded in the genotypes CCB-29, CCB-36 and CCB-5. It was also observed that maximum staple length, strength and desirable micronaire were registered in CCB-29, CCB-36, CCB-5 and CCB-11. The correlation coefficients showed that the days taken to first flower, number of nodes in lower first sympodial branch, bolls formed at 150 days, number of bolls per plant have significant positive correlations with seed cotton yield. The positive correlations of yield components with seed cotton yield are reliable and more effective and efficient indicators for selecting early maturing genotypes in Egyptian cotton.

Variability studies revealed that considerable amount of variability exist in the F2 population of rice cross CB 08504 × Prasanna through high values of PCV and GCV for characters like number of filled grains per panicle, spikelet fertility percentage and single plant yield. High PCV and moderate GCV was observed for number of productive tillers per plant while moderate PCV and GCV was recorded for days to first flowering and harvest index. High heritability coupled with high genetic advance as percent of mean was observed for the characters namely number of filled grains per panicle, number of productive tillers per plant, spikelet fertility percentage and single plant yield in the F2 population. The traits days to first flowering, number of productive tillers per plant, panicle length, number of filled grains per panicle, spikelet fertility percentage and harvest index were showing significant and positive correlation with single plant yield. The F2 population of CB 08504 × Prasanna performed better for earliness, yield and yield associated traits and could be utilised in future breeding programs to meet the increasing demand of rice.

In the present study, 225 germplasm collections of cowpea including local types were evaluated in augmented design alongwith C152 (check) for high test weight, desirable seed and pod features, earliness and resistance to Cowpea rust (Uromycesvignae), Cowpea Mosaic Virus (CMV) and Cercospora leaf spot for two years ( kharif 2008 and kharif 2009) at Dharwad. Theresults of the investigation revealed that fifteen of the accessions showed bold seeds (test weight > 10g). Accession numberIC202932 and IC247435 showed extra bold seeds (test weight >14g) and also bold pods. About 15 germplasm accessions werefound to be highly resistant to rust; 10 accessions displayed HR reaction to CMV and about 5 accessions showed highlyresistant reaction against leafspot. With respect to Multiple Disease Resistance, accession numbers IC201095, IC257406,IC257435 showed highly resistant reaction against leaf spot and CMV and accessions IC257410 and IC214753 showedresistance against rust and leaf spot. Some of the accessions identified against earliness are IC201087, IC201099,IC202707and IC202709 (68-75 days maturity). Such of the superior germplasm lines identified for earliness, multiple diseaseresistance, bold seed (100 seed weight > 12g) and desirable seed features would be further useful in Cowpea breeding programas parents.

The present investigation was conducted on okra (Abelmoschus esculentus) to determine the extent of heterosis for 12 traits, including fruit yield and its attributing traits. A total of 28 F1s produced by crossing seven lines with four testers of okra in Line x Tester fashion were evaluated along with standard check during late Kharif 2022 season. The cross C20-HRB-55 x Varsha Uphar recorded best heterobeltiosis and the cross C10-VRO-4 x Azad Ganga recorded best standard heterosis for yield plant-1. The cross C10- VRO-4 x Azad Ganga showed negative heterosis over better parent and standard check for the traits days to 50% flowering and days to first picking. The F1 hybrid C10- VRO-4 x Azad Ganga, which has a high potential for yield can be evaluated further for early Kharif season in Punjab.

Variability studies revealed that considerable amount of variability exist in the F2 population of rice cross CB 08504 × Prasanna through high values of PCV and GCV for characters like number of filled grains per panicle, spikelet fertility percentage and single plant yield. High PCV and moderate GCV was observed for number of productive tillers per plant while moderate PCV and GCV was recorded for days to first flowering and harvest index. High heritability coupled with high genetic advance as percent of mean was observed for the characters namely number of filled grains per panicle, number of productive tillers per plant, spikelet fertility percentage and single plant yield in the F2 population. The traits days to first flowering, number of productive tillers per plant, panicle length, number of filled grains per panicle, spikelet fertility percentage and harvest index were showing significant and positive correlation with single plant yield. The F2 population of CB 08504 × Prasanna performed better for earliness, yield and yield associated traits and could be utilised in future breeding programs to meet the increasing demand of rice. [ABSTRACT FROM AUTHOR]

Combining ability analysis using eight parents and their 28 F1 crosses of bitter gourd obtained from diallel mating design (excluding reciprocals) for yield and earliness indicated that non-additive gene action played major role than additive gene action in inheritance of the traits. Among the parents, IC-04448, IC-470560, IC-470558 and IC-085622 were found good general combiner for yield attributing characters and earliness hence, these parents can be exploited for hybridization for producing desirable recombinants in the segregating generations. High sca effects for yield and related characters were exhibited by IC-044438 × IC-045339 followed by IC-044417 × IC-470558 and IC-045339 × IC-085622. For earliness the crosses viz., IC-044438 × IC-045339, IC-045339 × IC-470550 and IC-045339 × IC-470558 were identified as promising ones. Most good specific cross combinations involved High × Low and Low × Low general combiners. Five crosses were identified for developing high yielding genotypes of bitter gourd. [ABSTRACT FROM AUTHOR]

Selection for earliness, high yield, quality pods, resistance to pests and diseases are the major aims in the French bean. Selection and identification of French bean variety suitable for cultivation are needed. Collections were made at the Nilgiris district and based on evaluation, French bean variety Ooty 3 (pole type) was selected as a pure line. Initially, sixteen different genotypes were collected from different locations and evaluated at Horticultural Research Station, Ooty. A single plant namely PvP5-1 was selected from Nilgiris local based on improvement in pod length, pod number, pod weight, pod circumference and yield per plant. The yield performance of Ooty 3 was superior over check in all the Multi-Location Trials, Adaptive Research Trial and large-scale evaluation trials. Due to its consistent superior performance, it was released as a French bean variety, Ooty 3 during 2018 duly approved by the Crop Scientist Meet, 2017 held at Tamil Nadu Agricultural University and Tamil Nadu State variety release committee to cater for the needs of Tamil Nadu farmers thereby increasing the yield level.

Cotton breeding programs aim to develop early-maturing varieties that yield high. Towards this, a study was conducted at the Agricultural Research Station, Dharwad farm, during kharif 2021-22 comprising 20 genotypes. Thirteen early maturity-related traits, along with seed cotton yield were analyzed. The examination indicated significant disparities in the early maturity traits viz., days to first flower (DFF), days to first boll opening (DFB), per cent crop harvested at the first (PCH-1) and second pickings (PCH-2), Bartlett’s Index (BI), node number of the first fruiting branch (NNFFB), plant height (PH), earliness percentage (EP), mean maturity date (MMD) and production rate index (PRI). Some traits, including PCH-1, PCH-2 and PRI presented higher estimations of GCV and PCV, along with high heritability and genetic advance, making them reliable indicators for selection. Seed cotton yield showed a significant negative correlation with DFF, DFB and MMD. Conversely, it showed a significant positive correlation with the PRI, PCH-1, PCH-2 and BI. Furthermore, DFB and PRI exhibited highly significant direct positive effects, while DFF had a negative direct effect, followed by the FBP. Based on this study, the genotypes ESS-3, ESS-20, NNDC-30 and S-32 were identified as early-maturing compared to ESS-13, FLT-25 and URT-21. These genetically diverse genotypes can be valuable resources for forthcoming cotton breeding programs. [ABSTRACT FROM AUTHOR]

Grain yield is a polygenically controlled trait which depends on many other component characters. But all the component characters are not directly associated with seed yield. Trait based yield improvement is always convenient for the plant breeders. In the present investigation, association analysis was carried out with five greengram genotypes (VGG 15-030, VGG 16-029, VGG 16-046, VGG 16-058 and VBN (Gg)2) of different duration, pod length and seed weight categories. Among the five genotypes, VGG 16-058 an extra early (55 days) and bold seeded (5.24g). VGG 15-030 was small seeded (2.94 g) genotype with small pod length (7.8 cm). Association analysis revealed that, in all the duration, pod length and seed weight categories, number of branches per plant, number of clusters per plant and number of pods per cluster was positively correlated with seed yield per plant. Genotype (VGG 16-029) with long pod (10.1 cm) and medium sized seed (4.4 g) alone had positive and significant association of all the yield traits with seed yield per plant. Besides, number of branches per plant, number of clusters per plant, number of pods per cluster, the other yield attributes also can be considered like long pod (>10 cm) and medium sized seed (3.0-5.0 g) category as important parameters for the improvement of greengram yield.

The present investigation was carried out with 56 cluster bean genotypes during Kharif 2018 using Randomized Block Design with two replications. Significant variations were recorded among the genotypes for growth, yield and quality characters. Thar Bhadavi recorded higher plant height at 30 DAS whereas Chitra Gold and IC-116930 were the tallest at 60 DAS and at final harvest respectively. The genotypes; IC-52249, Thar Bhadavi and the check Pusa Navbahar were the earliest to reach flower initiation whereas IC-116779, IC-116705, IC-522399 and IC-522506 reached 50% flowering earlier. The check Pusa Navbahar recorded the highest yield per plant. Highest protein content of pods was recorded by IC-113281 while high TSS of pods was recorded by IC-116660. Hence, these genotypes can be included in breeding programme for the improvement of respective characters.

Line × Tester analysis was carried out in a set of 20 crosses developed using five lines and four testers to ascertain the nature of gene action and combining ability of parents for yield, yield attributes and quality traits in groundnut. The estimates of GCA and SCA variance indicated the predominance of non-additive gene action for the inheritance of all the traits except SCMR at 60 DAS. The parents TCGS 1694, TCGS 1862, Kadiri-6 and TCGS 2251 were identified as good general combiners which could be further used in breeding programmes for yield improvement. The cross, Kadiri-6 × TCGS 1862 exhibited desirable sca effects for days to maturity, number of secondary branches plant-1, number of pods plant-1, number of mature pods plant-1 and kernel yield plant-1, while the cross Narayani × TCGS 2251 was found to be a good combiner with high sca effects for earliness (days to flowering and days to maturity). These two combinationshad either low × high or high × medium gca parents indicating the involvement of both additive and non-additive gene action. [ABSTRACT FROM AUTHOR]

The efficiency of the assignment of germplasm lines into heterotic groups is a prerequisite for obtaining useful heterotic patterns among germplasm lines. Therefore, this study was conducted to group lines into heterotic group besides assess the effects of both general and specific abilities. Fifteen white maize parental lines were crossed with two testers, i.e. parental line SK-12 and Single cross 120 at Agricultural Research Station in Sakha, Egypt during 2021 summer season. The resultant 30 crosses were evaluated along with four commercial hybrids in three locations during 2022. The parental inbred lines Sk5001/42, Sk5003/48, Sk5003/53, Sk5004/55 and Sk5004/56 recorded positive GCA effect on grain yield while Sk5001/41, Sk5002/46 and Sk5004/56 exhibited desirable GCA effects for earliness. Five single crosses viz. (Sk5003/53 × Sk12), (Sk5001/42 × Sk12), (Sk5004/55 × Sk12), (Sk5003/48 × Sk12) and (Sk5004/56 × Sk12) and two three way crosses (Sk5001/42 × SC.120) and (Sk5003/53 × SC.120) did not differ significantly against their respective check hybrids (SC 10 and TWC 321) though they outyield their respective checks. These hybrids could be subjected to further multi-location evaluation to assess the yield stability for commercial exploitation. Two groups of parental lines were created based on Heterotic Group Specific and General Combining Ability (HSGCA) method for grain yield trait. These groups might be employed in a breeding program to pick the best parents to make crosses in other combinations. [ABSTRACT FROM AUTHOR]

Sunflower (Helianthus annuus L.) is one of the most important oilseed crops grown worldwide because of its supreme oil quality and commercial importance. Assessment of diversity among inbreds is a vital prerequisite to select parents for a hybridization programme. Hence, in the present investigation, the genetic divergence of 29 genotypes consisting of both maintainer and restorer inbreds was studied using Mahalanobis (D2 ) analysis. Genotypes were grouped into eight clusters, in which cluster I was the largest with 13 genotypes. Clusters IV, VI, VII and VIII were the smallest, with one genotype each. The maximum intracluster distance was observed in cluster I followed by II. Maximum inter cluster distance was recorded between clusters II and V followed by clusters II and VII. Days to 50% flowering had the maximum contribution (32.76%) for genetic divergence. Superior mean performance for head diameter, 100 - seed weight, seed yield per plant and oil content was observed in cluster VI whereas earliness in terms of days to 50% flowering and days to maturity was observed in cluster II. Cluster VIII recorded superior mean performance for volume weight and the lowest mean plant height was observed in cluster VII. Hence, hybridization between cluster II (CMS 10B, HA 89B, RHA-1-1) and cluster V (CMS 519B, HA 430B) could create more variability in the segregating generations. [ABSTRACT FROM AUTHOR]

The present study was carried out to elucidate the mutagenic efficiency of gamma rays (100 Gy, 150 Gy), electron beam (100 Gy, 150 Gy) used alone and in combination with EMS (30mM) as a recurrent treatment in the subsequent generation of Anna (R) 4 rice cultivar. The study was aimed to analyse the induced genetic variability, mean performance as well as population characteristics for various quantitative traits in M2 generation. The mutant lines were selected based on earliness, grain shape and yield. In general, bidirectional shift without any uniform trend was observed for all the traits except productive tillers per plant and grain weight. Recurrent EMS approach had no significant effect on earliness, however, it had significant effect on reduction of plant height (8.19%) and productive tillers per plant (25.27%) in EB 150Gy + EMS 30mM. Whereas 150 Gy gamma irradiation had increased effect on grains per panicle (21.99%), panicle weight (34.73%) and grain yield per plant (9.77%). Though selection was exercised for desirable traits, co-efficient of variation was still higher for productive tillers per plant (31.90%), grains per panicle (30.20%), panicle weight (30.87%) and grain yield per plant (31.55%). From the mean performance and population characteristics, it is concluded that recurrent EMS mutagenic approach was less efficient than irradiation for induction of desirable changes in earliness, grain shape, grain yield and other quantitative traits. [ABSTRACT FROM AUTHOR]

The present investigation was conducted in okra to study the magnitude of heterosis and to identify potential parents and superior cross combinations for twelve plant traits including fruit yield and its component traits. Forty five F1s were developed by crossing 10 elite lines of okra in half diallel fashion during summer 2016. All 45 F1s along with their 10 parents and one standard check (Nunhems hybrid Shakti) were evaluated in a randomized complete block design with three replications during late kharif (July to October) 2016 at ICAR-KrishiVigyan Kendra, Babbur Farm, Hiriyur, Chitradurga, Karnataka. The results revealed wide range of heterotic pattern for different traits. For first fruit producing node, heterosis over standard control ranged from -9.03 to 43.32, respectively. For days to 50% flowering, heterosis over standard control ranged from -8.70 to 0.72, respectively and for total yield per plant, heterosis over standard control ranged from -0.13 to 168.55,respectively. The overall maximum positive significant heterosis for total yield per plant was observed in cross IIHR-875 x IIHR-478 (168.55%) over standard heterosis. Negatively heterotic crosses like IIHR-562 x IIHR-444 for days to 50% flowering (-8.70%) and IIHR-567 x IIHR-107 for fruiting nodes (-9.03%) respectively, are important to exploit heterosis for earliness in okra. Out of 45 F1s, 44 F1s crosses exhibit significant standard heterosis in any given direction for total yield per plant except cross IIHR-604 x IIHR-107 (-0.13%). The F1 hybrid IIHR-875 x IIHR-478 with high yield potential has the potential for commercial cultivation after further evaluation for late kharif season of Karnataka. [ABSTRACT FROM AUTHOR]

Diverse source of early genotypes is obligatory for breeding high yielding early castor (Ricinus communis L.) cultivars. One hundred and twenty-five medium duration genotypes including three checks were evaluated for the presence of genetic diversity and variability. Genetic distance, variance components and correlation coefficients were estimated for seven seed related quantitative traits. Significant genotypic differences were observed among the collections for these traits. High heritability and high genetic advance were noticed for seed length, seed breadth, Length/Breadth ratio, shelling percentage, 100 seed weight and seed yield per plant, thus mode of gene action reported was additive. Genetic diversity analysis based on dendrogram, phenogram and circular form grouped the entries into seven groups and it computed inter and intra cluster distance. Principal Component Analysis (PCA) revealed that the first three components cumulatively accounted for 72.57 per cent of the total variation. Seed yield per plant showed a significant association with shelling percentage and 100 seed weight. Also, direct effects were high and positive through seed breadth, Length/Breadth ratio and 100 seed weight. The promising genotypes identified (ICIRG 2272103 and RG 1673) and the information generated would be useful for breeding early/medium cultivars as well to understand the physiological mechanism related to earliness in castor. [ABSTRACT FROM AUTHOR]

In the present study, 60 rice genotypes were selected to evaluate the genetic divergence for 15 yield and yield attributing characters. Based on Mahalanobis D2 statistic, the 60 genotypes were grouped into nine clusters. On the basis of genetic distance and cluster means, clusters IV and IX, VI and IX, I and IX, were identified as clusters with high inter-cluster distance. Genotypes of these clusters could be used as parents in crop improvement programmes for generation of promising segregants. Days to maturity and thousand grain weight were observed to contribute highly towards divergence. Hybridisation between the genotypes SMB3 (cluster VIII) and Juma (cluster IV) could be recommended for recombination breeding to get superior transgressive segregants for earliness and desirable yield attributing characters. [ABSTRACT FROM AUTHOR]

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 x L-7, T-1 x L-13, T-1 x L-17, T-2 x L-4, T-2 x L-5, T-2 x L-10 and T-2 x 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. [ABSTRACT FROM AUTHOR]

Seven cucumber (Cucumissativus L.) genotypes (3 lines and 4 testers) were crossed in a line X tester mating design. The resultant 12 hybrids and their parents were evaluated using Randomised Block Design with two replications during Kharif 2018. Sufficient genetic variability was observed for all the characters under study. In this study, the parents L2 (Koradacherry local), T2 (Orathanadu local) and T3 (Aipatti local) exhibited high positive GCA (General Combining Ability) effects for yield related traits and high negative GCA effects for earliness characters. The parent T2 identified in this study may be used in multiple crossing programme to isolate high yielding varieties. Among the hybrid combinations, L2xT3, L1xT2 and L3xT4 expressed the maximum positive significant SCA (Specific Combining Ability) effects for yield and yield associated characters. In the above cross combinations one parent was a good combiner and the other was an average/poor combiner; hence the hybrids can be exploited for transgressive selection. [ABSTRACT FROM AUTHOR]

The DUS test is an important tool for cataloguing the genotypes and utilization of variants in the crop improvement programme. In the present investigation, a total of 55 early duration pigeonpea genotypes were categorized by descriptors and cluster analysis for 21 agro morphological traits. Wide variations were observed in the characters viz., flower colour, a pattern of streaks, pod colour, seed colour, seed shape and size and no much variation was observed for the remaining traits. The traits viz., earliness and prominent type of pod constriction were identified in all the genotypes. The genotypes were partitioned into six clusters. Cluster I encompass 32 genotypes; cluster II consists of seven genotypes; four genotypes each were placed in clusters III and V; clusters IV and VI comprised of five and three genotypes, respectively. In the present study, the DUS descriptors and the variation observed in the early duration pigeonpea genotypes will form the basis for designing the pigeonpea improvement programme. [ABSTRACT FROM AUTHOR]

White grained finger millet genotypes has become a thrust area in finger millet breeding due to increased demand of nonglutinous food products and lesser acceptability of brown grained finger millet. Sixteen white grain finger millet lines were developed by crossing extra early maturing brown grained finger millet genotypes including adapted varieties with late maturing white grained finger millet genotypes. The quantitative data of 16 lines along with parents were subjected to multivariate analysis. A wide range of variation was observed for all the studied traits. The parental lines of brown and white grained finger millet genotypes exhibited extreme values for grain yield and days to maturity whereas, the developed white grained genotypes showed moderate values. Projections of genotypes in PCA biplot showed close association of newly developed white grain genotypes VL 427, VL 360, VR 485, VR 443, VL 366, VR 425B, VR 425A and VL 356 with VL 201 (brown type) because of earliness and high yield potential. The cluster analysis further indicated that white grained genotypes from second cluster are probable candidates for further testing and release, and further refinement in breeding strategy by hybridizing white genotypes from second cluster with brown genotype in third cluster for incorporating earliness and high yield. [ABSTRACT FROM AUTHOR]

Towards understanding the nature of gene action for kernel yield and its components traits, a set of 45 F1 hybrids generated by adopting diallel mating design (Method IV and Model I) involving 10 inbred lines were tested across three seasons for their performance and combining ability. Combining ability analysis revealed that the mean sum of squares due to general and specific combining ability were significant indicating the contribution of both additive and non-additive gene action in controlling days to 50% flowering, days to 50% silking, anthesis-silking interval, days to maturity, plant height, SPAD chlorophyll meter reading, specific leaf area, cob length, cob girth, number of kernel rows per cob, number of kernels per row, 100 kernel weight, harvest index and kernel yield. Estimates of components of variances (σ² GCA and σ² SCA) and ratio of σ² GCA/σ² SCA indicated the predominance of non-additive gene action for all the characters studied. Among the inbred lines, BML 2, DFTY, Heypool and PDM 1474 were found to be the best general combiners across seasons for kernel yield and most of yield components as well as developmental characters. DFTY, Heypool, PDM 1452 and PAM 1474 were identified as good general combiners for earliness. Among the top 20 best performing hybrids, BML 15 × PDM 1452, BML 15 × PDM 1474 and BML 7 × DFTY were rated as promising hybrids based on their superior performance and sca effects for kernel yield and most of the yield components. These hybrids could be recommended for commercial cultivation after extensive testing in multilocation trials. [ABSTRACT FROM AUTHOR]

Genetic divergence analysis following Mahalanobis D2 statistics revealed considerable genetic diversity among 46 genotypes of Okra (Abelmoschus esculentus (L) Moench) for all the fourteen quantitative characters pertaining to growth, earliness and yield. Forty six genotypes were grouped into five distinct clusters depending up on the similarities of their D2 values following Tocher’s method. The germplasm collected from same place scatted in to different clusters indicating genetic diversity not parallel with geographical diversity. Appreciable diversity within and between five clusters was observed. The traits viz., yield per plot (36.45%), plant height (26.27%), number of seeds per plant (16.83%), number of fruits per plant (6.47%) and yield per plant (4. 53%) were the potent factors in differentiating the germplasm of okra under study. The use of diverse genotypes from the clusters with high inter cluster distance (clusters IV and V, III and IV, I and IV and II and IV) in hybridization is expected to result in high heterosis and throw desirable transgressive segregants. [ABSTRACT FROM AUTHOR]

An investigation was conducted to evaluate the F2 population of two crosses of barnyard millet viz., cross I, ACM-15-343 X IEC 82 and cross II, Co (Kv) 2 X IEC 107 for extra earliness. Genetic variability and association analyses were carried out for sixteen biometrical traits. In both the crosses, high PCV and GCV was observed for the width of flag leaf, length of a lower raceme, number of racemes and grain yield per plant. Low PCV and GCV was observed for days to maturity. The minimum difference between PCV and GCV was observed for all the traits in both crosses, indicating the negligible effect of environment on the expression of the characters. Moderate to high heritability with moderate to high genetic advance in all the traits revealed the predominance of additive gene action. A positive significant correlation was noted for grain yield with plant height, days to flowering, days to maturity, the number and length of nodes, the number of basal tillers, stem diameter and single ear head weight. Path analysis disclosed a high positive direct effect of the number of basal tillers and single ear head weight on yield. These results together help in the selection of superior segregants based on the number of basal tillers and single ear head weight in forwarding them to successive generations. [ABSTRACT FROM AUTHOR]

Twelve parental genotypes and twenty F1 hybrids developed in a Line x Tester fashion were used in the present study to estimate gene action, combining ability and standard heterosis for eleven quantitative and five quality traits in cotton. All the traits studied exhibited greater SCA variance than GCA except days to fifty per cent flowering suggesting that these traits are controlled by dominant gene action. Among the parents used, SVPR 2 and TSH 325 were detected with higher general combining ability for seed cotton yield and should be given importance while developing hybrids or recombinants. The hybrids namely SVPR 2 x TSH 325, SVPR 2 x Suraj and GJHV 370 x PBH 116 were identified as the best hybrids for seed cotton yield and SVPR 2 x TCH 1828 for fibre properties and recommended for heterosis breeding. Besides, the hybrid between GJHV 370 x CPD 1702 was suggested for recombination breeding for earliness and ginning percentage as it fulfilled the criteria of non-significant sca effects for hybrid and significant gca effects for respective parents. [ABSTRACT FROM AUTHOR]

This study was conducted to estimate combing ability in bottle gourd. Fifty eight bottle gourd genotypes comprising 45 hybrids, 10 parents and 3 checks were evaluated in three different environments. The data were analyzed as per Method-II, Model-I of Griffing (1956). Significant GCA effects in desirable direction was evident in the inbred lines P6, P2 and SCA in hybrids P9 x P10, P4 x P6 for days to first harvest on pooled basis for number of branches per vine. The lines with significantly positive GCA effects for number of branches per vine were P5, P6 and hybrids for SCA effects were P3 x P8, P3 x P6 on pooled basis for days to first harvest. For rind thickness the lines with significantly positive GCA effects for rind thickness were P1, P5 and hybrids with significant SCA effects were P8 x P10, P1 x P9, and P1 x P8 on pooled basis. On pooled basis, inbred line P9 was the best general combiner with highly significant and positive GCA effect and the hybrids with significant SCA effects in desirable direction were possessed by P7 x P10 for flesh thicknes. Significantly positive GCA effects for rind thickness were noted in the inbreds, P1, P5 and significant SCA effects in the hybrids were noted in P8 x P10 P1 x P9 on pooled basis for fruit diameter. Significant GCA effects, On pooled basis, in positive direction, was observed in the inbred lines P8, P4 and SCA effects in hybrids P6 x P9 in positive direction followed by the hybrid P6 x P8, P7 x P8, P4 x P7 and P4 x P10 for yield per square meter. These genotypes could be useful in future breeding programmes for development of hybrids in bottle gourd. [ABSTRACT FROM AUTHOR]

Twelve F1 hybrids of cucumber derived from a top cross involving twelve monoecious parents and a stable gynoecious inbred (EC 709119) as female parent were evaluated in randomized block design (RBD) with three replications to assess general combining ability (GCA). Significant GCA effects were observed for all the characters except days to first male flower anthesis. The estimates of GCA effects revealed that none of the parents exhibited good GCA for all the characters together. Among 12 parents, CS123 was observed as the good general combiner for fruit yield per vine, length of main vine, branches per plant, number of harvests, duration of the crop, fruits per plant and number of seeds per fruit. The parents, CS128 and IC 538186 were general good combiners for earliness. The parent CS127 was found to be superior for fruit length, weight and girth. [ABSTRACT FROM AUTHOR]

An investigation was conducted at the University orchard, Department of Vegetable crops, Horticultural College and Research Institute, Tamil Nadu Agricultural University, Coimbatore during the year 2010-2011 to evaluate the germplasm consisted of 182 accessions along with six check varieties viz., Pusa purple Long, Pusa Shyamala, Pusa Kranti, Punjab Sadabahar (received from National Bureau of Plant Genetic Resources, New Delhi) and CO1 and CO2 (released from TNAU, Coimbatore) were taken for evaluation. They were evaluated for their plant, fruit characters along with shoot and fruit borer infestation. The study showed that the accessions viz., IC 354546, IC 112736 and EC 467272 were identified as best performers as they showed favourable characters for earliness to flowering and harvest, number of fruits / plant and yield. Also they recorded lowest level of shoot and fruit borer infestation and high marketable yield. [ABSTRACT FROM AUTHOR]

Combining ability studies involving five females and four males revealed the presence of significant differences due to lines, testers and line × testers, indicating the presence of variability. The estimates of variance components exhibited presence of additive gene action for days to flowering, maturity and grain yield studied. Considering the general combining ability effects of parents for days to flowering, maturity and grain yield, female SL-9B and males SLR-57 and SLR-30 were good general combiners for grain yield and the female SL-39B and male SLR-66 were good general combiners for earliness. The crosses 104B × SLR-30, SL-9B × SLR-57, SL-9B × SLR-30 and 104B × SLR-57 were identified promising for improving grain yield while crosses SL-19B × SLR-66, SL-9B × SLR-66 and SL-39B × SLR-57 have been selected for breeding forearliness. [ABSTRACT FROM AUTHOR]