Correlations between quantitative traits of winter common wheat-breeding tool for increasing grain yield

N. Tsenov1*, T. Gubatov1, I. Yanchev2

1Department of Wheat Breeding and Technology, Agronom Breeding Company, 9300 Dobrich, Bulgaria
2Department of Plant Science, Faculty of Agronomy, Agricultural University, 4000 Plovdiv, Bulgaria

(Manuscript received 7 November 2020; accepted for publication 15 April 2021)

Abstract. Information on the relationships between quantitative traits affecting yields is extremely important for winter wheat. For it, the annual genotype*environment interaction is palpable and often masks the influence of individual traits on grain yield. The aim of the study is to determine the traits through the selection of which the grain yield could be significantly increased in the future. The data from three field multifactorial experiments were used (FERT, PGR, ABC), in which a significant influence of various factors (year, point, density, fertilization) on the size and variation of all studied traits was established. In the database thus formed the observed strong variance in the values of the traits is a great prerequisite for the established correlations to be accepted with a high degree of reliability. The mutual influence in the formation of each of the traits is a good basis for their grouping, according to the type of their effect on yield. 1) The characteristics, number of grains per m2 (NGm), grain weight per spike (WGS) and number of productive tillers per m2 (NPT) have a significantly positive effect on grain yield, 2) the weight per 1000 grains (TGW) and number of grains in spike (NGS) are traits that have a direct effect, but it is unstable in manifestation and 3) the traits, as height of stem (HOS), total plant biomass (TBM), and harvest index (HI) do not show a direct effect on grain yields. A significant increase in yield in the breeding of winter wheat can be achieved by increasing the number of grains per unit area (NGm). This is possible while maintaining the achieved level of number of grains in spike (NGS) with a parallel increase of tillering productive ability (NPT). The increase of this trait by selection should be taken into account when reducing the grain size (TGW). This will increase the chance of increasing the number of grains in the spike (NGS), will reduce the weight of the grain per spike (WGS), which in turn will be a prerequisite for optimizing the stability of lodging.

Date of ear emergence: a factor for notable changing the grain yield of modern winter wheat varieties in different environments of Bulgaria

N. Tsenov1*, T. Gubatov1, I. Yanchev2

1 Department of Wheat Breeding and Technology, Agronom Breeding Company, 9300 Dobrich, Bulgaria
2 Department of Plant Science, Faculty of Agronomy, Agricultural University, 4000 Plovdiv, Bulgaria

(Manuscript received 2 November 2020; accepted for publication 15 January 2020)

Abstract. Wheat is a crop with a very long growing season, during which it is subjected to prolonged exposure to many environmental factors. For this reason, the interaction of genotype with conditions is very common for any character of wheat. This study aims to determine whether the grain yield is affected by the change of the ear emergence date (EED) in various environments. In a four-year period, 30 current for national real grain production winter wheat varieties were studied. The EED and grain yield (GY) were studied as quantitative traits within five locations of the country having various soil and climatic conditions. Using several statistical programs, genotype x environment interaction of two traits was analyzed. The emphasis on data analysis was whether changes of traits due to the conditions were related and that the optimization of the ear emergence date could serve as a breeding tool for increasing grain yield. The date of ear emergence and grain yield are traits that are reliably influenced by growing conditions. The change in the date of emergence is mainly of the linear type, while the grain yield shows linear and nonlinear type changes in the same environmental conditions. It was found that the key roles in the change of characteristics are the conditions of the year, with the relatively weakest impact of the genotype on them. There is a positive relationship between the two traits, although their change depends on environmental factors. Although they change to different degrees and in relation to each other, there is a positive correlation between them. The more favorable the environmental conditions, the weaker the relationship between these two traits and vice versa. Under changing climatic conditions, the change in the relationship between the two traits is a signal of the need to create different varieties by date of ear emergence in order to obtain higher yields in the future.

 

Morphological characterization and genetic analysis in bread wheat germplasm: A combined study of heritability, genetic variance, genetic divergence and association of characters

  1. Gerema1*, D. Lule2, F. Lemessa4, T. Mekonnen3

1Bako Agriculture Research Center, Oromia, Ethiopia

2Oromia Agriculture Research Institute, Finfinne, Ethiopia

3Institute of Biotechnology, Addiss Ababa University, Ethiopia

4Department of Horticulture and plant Science, Jimma University, Jimma, Ethiopia

(Manuscript received 20 May 2020; accepted for publication 5 November 2020)

Abstract. The present study was conducted to assess the nature and magnitude of genetic variability and traits association of bread wheat genotypes for yield and related traits. A total of 180 genotypes were evaluated in alpha lattice design with three replications in 2017/18 cropping season. Data for 10 quantitative traits were collected and subjected to analysis of variance. The result from the analysis of variance revealed highly significant variability observed among genotypes for all traits studied. Phenotypic coefficient of variation (PCV) is superior over genotypic coefficient of variation (GCV) for most traits but narrow variations were found between PCV and GCV for most of the traits. Heritability in broad sense and genetic advance as percent of the mean (GA%) were relatively higher for Kernels per spike and grain filling period. Grain yield showed positive and highly significant (p≤0.01) association with number of tillers, kernel per spike and plant height both on genotypic and phenotypic levels.The path coefficient analysis showed that spike length, plant height and kernels per spike had positive direct effect on grain yield on both genotypic and phenotypic levels. Divergence analysis (D2) grouped the total test germplasm into 10 clusters. Among those, clusters IV and IX showed the highest genetic distance and thus the possibility to develop segregating populations upon the crossing of widely related genotypes in those clusters. The results could help researches to utilize the most promising wheat genotypes of this study in future breeding programmes for enhancing desirable traits.

Correlations between grain yield and related traits in winter wheat under multi-environmental traits

  1. Tsenov1*, T. Gubatov1, I. Yanchev2

 

1Department of Wheat Breeding and Technology, Agronom Breeding Company, 9300 Dobrich, Bulgaria

2Department of Plant Science, Faculty of Agronomy, Agricultural University, 4000 Plovdiv, Bulgaria

(Manuscript received 7 August 2020; accepted for publication 29 October 2020)

Abstract. In a series of field trials, a database of quantitative traits associated with winter wheat grain yield has been collected. The aim of the present study is to determine the relationships between the winter wheat (Triticum aestivum L.) traits of productivity in environments causing the maximum possible variation of each of the traits. In order to determine the correlations between the quantitative characters studied, all possible statistical methods have been applied (regression analysis, PCA, Multiple Correspondence analysis), which complement each other. It was found that the nature of the correlations between traits depends to a large extent on the methods for their evaluation. There are high and significant correlations between grain yields and the grain number per spike (weight of grain per spike and number of grains per m2) even under strong genotype by environment interaction of all the traits in trails. The established results are related to possible options for increasing winter wheat grain yield by breeding.

Productivity and yield stability at late treatment of durum wheat (Triticum durum Desf.) with antibroadleaved herbicides.

Gr. Delchev*, S. Angelova

Department of Plant Production, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria

(Manuscript received 5 July 2018; accepted for publication 1 February 2019)

Abstract. The aim of the study was to investigate the productivity and yield stability at durum wheat (Triticum durum Desf.) treated with antibroadleaved herbicides during 3-rd stem node stage. The experiment was conducted during 2012-2014 on pellic vertisol soil type. Under investigation was Bulgarian durum wheat cultivar Victoria (Triticum durum var. valenciae). A total of 20 antibroadleaved herbicides were tested: Granstar 75 DF, Granstar super 50 SG, Ally max SG, Arat, Biathlon 4 D, Derby super WG, Mustang 306.25 SC, Weedmaster 646 CL, Sunsac, Secator OD, Logran 60 WG, Lintur 70 WG, Akurat 60 WG, Akurat extra WG, Eagle 75 DF, Herbaflex, Starane 250 EK, Sanafen, Dicotex 400 and Herby 675. All herbicides were treated in 3-rd stem node stage of durum wheat. It was found that during 3-rd stem node stage of durum wheat the antibroadleaved herbicides Arat, Biathlon, Derby super, Secator, Lintur, Akurat, Akurat extra and Starane can be used. These herbicides do not have a negative influence on grain yield. The most unstable yield is obtained after the treatment with herbicides Granstar, Granstar super, Ally max, Sunsac, Logran, Eagle, Herbaflex and Herby. Their selectivity to durum wheat is influenced most strongly by weather conditions during the vegetation period. From the viewpoint of technology for durum wheat growing, during 3-rd stem node stage technologically the most valuable are herbicides Derby super, Arat, Biathlon, Secator, Akurat, Akurat extra and Lintur. After the treatment with them high grain yield with high stability with relation to different years is obtained. The herbicides Granstar, Granstar super, Ally max, Sunsac, Weedmaster, Logran, Eagle, Herbaflex, Sanafen, Dicotex and Herby cannot be used during 3-rd stem node stage of durum wheat.

Effect of conservation agriculture on grain yield and income of maize under maize based cropping system in far western Nepal

H.K. Prasai1*, S.K. Sah2, A.K. Gautam3, A.P. Regmi3

1Nepal Agricultural Research Council, Regional Agricultural Research Station, 10801 Bhagetada, Dipayal, Doti, Nepal 2Agriculture and Forestry University, Rampur, 44209 Chitwan, Nepal
3Nepal Agricultural Research Council, Singh Durbar Plaza, 44617 Kathmandu, Nepal

(Manuscript received 1 September 2018; accepted for publication 25 October 2018)

Abstract. The adoption of Conservation agriculture (CA) contributes to sustainable production and its advantages include lower inputs and stable yields. This study was conducted in the research field of Regional Agricultural Research Station, Bhagetada, Dipayal, Doti during 2014 and 2015 to identify the effect of CA on grain yield and income of maize in Maize based cropping system. Both conservation and conventional agricultural (ConvA) practices were evaluated on two maize based cropping systems namely maize-wheat-mungbean (M-W-MB) and maize-lentil-mungbean (M-L-MB). For this purpose two maize varieties namely Raj Kumar and Arun-2 were used. The average productivity of maize under M-L-MB cropping system was 1.6% higher (5.75 t/ha) than M-W-MB cropping system (5.66 t/ha). The average grain yield of maize under CA was 16.7% higher (6.15 t/ha) than ConvA (5.27 t/ha). Rajkumar produced 43% higher average grain yield (6.73 t/ha) than Arun-2 variety (4.69 t/ha). The average net benefit was slightly higher (US$ 597.33/ha) under M-L-MB cropping system than M-W-MB cropping system (US$ 573.89/ha). Similarly, the average net benefit from CA was 102% higher (US$ 783.67/ha) than ConvA (US$ 386.79/ha). Rajkumar variety gave 127% higher average net benefit (US$ 813.49/ha) than Arun-2 (US$ 357.81/ha). The average benefit – cost (B:C) ratio of M-L-MB cropping system was slightly higher (1.72) than the average B:C ratio of M-W-MB cropping system (1.70). The average B:C ratio of CA was 42% higher (2.01) than ConvA (1.41). The average B:C ratio of Rajkumar variety was found 33% higher (1.95) than Arun-2 (1.46). The higher grain yield, net profit and B:C ratio were found in CA practices under M-L-MB cropping system and Rajkumar variety. This study suggests that hybrid maize planting and the adoption of M-L-MB cropping system should be used to increase grain yield and economic performance under CA practices.

Productivity and yield stability at late treatment of durum wheat (Triticum durum Desf.) with antibroadleaved herbicides II. Influence at treatment during 2-nd stem node stage

Gr. Delchev*, M. Delcheva

Department of Plant Production, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria

(Manuscript received 17 May 2018; accepted for publication 16 October 2018)

Abstract. Theresearchwasconductedduring2012-2014onpellicvertisolsoiltype.InvestigatedwastheBulgariandurumwheatcultivarVictoria(Triticum durum var. valenciae). A total of 20 antibroadleaved herbicides were investigated: Granstar 75 DF, Granstar super 50 SG, Ally max SG, Arat, Biathlon 4 D, Derby super WG, Mustang 306.25 SC, Weedmaster 646 CL, Sunsac, Secator OD, Logran 60 WG, Lintur 70 WG, Akurat 60 WG, Akurat extra WG, Eagle 75 DF, Herbaflex, Starane 250 EK, Sanafen, Dicotex 400 and Herby 675. All herbicides were treated in 2-nd stem node stage of durum wheat. During 2-nd stem node stage of durum wheat the following antibroadleaved herbicides can be used: Arat, Biathlon, Derby super, Mustang, Secator, Lintur, Akurat, Akurat extra, Starane, Dicotex and Herby. These herbicides do not have a negative influence on grain yield. The most unstable treatments are with herbicides Granstar, Granstar super, Ally max, Sunsac, Logran, Eagle, Herbaflex and Herby. Their selectivity to durum wheat is influenced most strongly by weather conditions during the vegetation period. From the viewpoint of technology for durum wheat growing, during 2-nd stem node stage technologically the most valuable are the herbicides Derby super, Arat, Biathlon, Secator, Akurat, Akurat extra and Lintur. Their application provides high and stable grain yield during different years. The herbicides Granstar, Granstar super, Ally max, Sunsac, Weedmaster, Logran, Eagle and Herbaflex cannot be used during 2-nd stem node stage of durum wheat.

Productivity and yield stability at late treatment of durum wheat (Triticum durum Desf.) with antibroadleaved herbicides. I. Influence at treatment during 1-st stem node stage

Gr. Delchev, D. Delchev

 

Department of Plant Production, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria

 

DOI: 10.15547/ast.2018.03.043

(Manuscript received 25 May 2018; accepted for publication 20 July 2018)

 

Abstract. The research was conducted during 2012 – 2014 on pellic vertisol soil type. Under investigation was Bulgarian durum wheat cultivar Victoria (Triticum durum var. valenciae). A total of 20 antibroadleaved herbicides were investigated: Granstar 75 DF, Granstar super 50 SG, Ally max SG, Arat, Biathlon 4 D, Derby super WG, Mustang 306.25 SC, Weedmaster 646 CL, Sunsac, Secator OD, Logran 60 WG, Lintur 70 WG, Akurat 60 WG, Akurat extra WG, Eagle 75 DF, Herbaflex, Starane 250 EK, Sanafen, Dicotex 400 and Herby 675. All herbicides were treated in 1-st stem node stage of durum wheat. During 1-st stem node stage of durum wheat the antibroadleaved herbicides Arat, Biathlon, Derby super, Mustang, Weedmaster, Secator, Lintur, Akurat, Akurat extra, Eagle, Starane, Sanafen, Dicotex and Herby can be used. These herbicides do not have a negative influence on grain yield. The most unstable are herbicides Granstar, Granstar super, Ally max, Sunsac, Logran, Herbaflex and Herby. Their selectivity to durum wheat is influenced most strongly by weather conditions during the vegetation period. From the viewpoint of technology for durum wheat growing, during 1-st stem node stage technologically the most valuable are herbicide Derby super, Arat, Biathlon, Secator, Akurat, Akurat extra and Lintur. They combine high grain yield with high stability in relation to different years. The herbicides Granstar, Granstar super, Ally max, Sunsac, Logran and Herbaflex cannot be used during 1-st stem node stage of durum wheat.

 

Knezha 560 – a new mid-late maize hybrid

  1. V. Valkova, N. Petrovska

 

Maize Research Institute, 5835 Knezha, Bulgaria

 

DOI: 10.15547/ast.2018.03.036

(Manuscript received 14 May 2018; accepted for publication 29 June 2018)

 

Abstract. Тhe article presents a short characteristic of morphological, biological and economic qualities of a new maize hybrid Knezha (Kn) 560. The hybrid is a single cross, from mid-late group – FAO 500-599. It is recognized in 2017 by the Expert Commission of Executive Agency of Variety Testing, Field Inspection and Seed Control (EAVTFISC). At the points of ecological variety trails (EVT) and EAVTFISC it was compared with the American hybrid PR 35 P 12 and the Bulgarian hybrid – Knezha 509. During the testing period in the experimental field of the Maize Research Institute (MRI) – town of Knezha, the three-year average grain yield of hybrid Knezha 560 exceeded the standard PR 35 Р 12 hybrid by 19.3% and Knezha 509 hybrid by 37.3%. In the EAVTFISC system, the new hybrid exceeds the middle standard by 0.8%. The hybrid is stress-tolerant and resistant to economically important diseases and pests of maize. With this high-yielding and competitive maize hybrid, the group of mid-late maize hybrids offered on the Bulgarian seed market is being filled.

Agronomic performance of mutant lines of winter two-rowed barley

  1. Dyulgerova, D. Valcheva, N. Dyulgerov

 

Institute of Agriculture, 8400 Karnobat, Bulgaria

(Manuscript received 24 July 2017; accepted for publication 19 January 2018)

 

Abstract. The aim of this investigation was to study agronomic and morphological traits of winter two-rowed barley mutant lines in the M6 and M7 generations. Eight mutant lines, their parent – breeding line 244D and national standard cultivars – Obzor and Emon were evaluated in Complete Block Design with four replications. The research was conducted in the 2013/2014, 2014/2015 and 2015/2016 growing seasons in the experimental field of the Institute of Agriculture – Karnobat, Southeastern Bulgaria. The characters studied included days to heading, plant height, lodging, peduncle length, spike length, awn length, spikelet number per spike, grain number per spike, grain weight per spike, 1000 grains weight, grain yield, protein content, extract content and grading (>2.5mm). Mutant lines M1/3, M1/5 and M1/217 produced a significantly greater grain yield than the parent and standard cultivars. The improvement of grain yield was associated with increasing of spike length and grain weight per spike. The studied mutant lines were characterized with a high yield ability combined with other valuable agronomic traits and can be used in a breeding program for developing winter malting  barley varieties.