Use of the QTL approach to the study of soybean trait relationships in two populations of recombinant inbred lines at the F7 and F8 generations

This work aimed to identify the quantitative trait loci (QTL) associated with photosynthesis and growth and productivity traits of soybean and to study possible associations between these traits by the analysis of coincidence of QTL in linkage groups (LGs). Thus, populations of recombinant inbred lines (RILs) of the F7 and F8 generations derived from the cross between the varieties BARC-8 and Garimpo were used. The traits evaluated were net assimilation rate of CO2 under saturating light (Asat), potential photosynthesis rate (Pmax), leaf area (A), specific leaf area (SLA), specific leaf nitrogen (N); root (W R), nodule (W N), stem (W ST), leaf (W L), pod (W P) and plant dry mass (W T); nodule (nN), seed (n s), and pod number (nP); seed fresh mass per plant (W S), one-hundred seed fresh mass (W HS) and seed protein percentage (P%). It was possible to identify the following QTL associated with the following soybean traits: SLA, Asat, N, W R, W ST, W L, W T, W P, W HS, n s and nP, indicating that the RIL population has a great potential for mapping loci associated with quantitative traits of the soybean crop. The correlations between the soybean traits were partially confirmed by coincidence of QTL.

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Specificity of Prehaustorial Resistance to Puccinia hordei and to Two Inappropriate Rust Fungi in Barley

Phytopathology ◽

10.1094/phyto.1998.88.8.856 ◽

1998 ◽

Vol 88 (8) ◽

pp. 856-861 ◽

Cited By ~ 21

Author(s):

T. J. H. Hoogkamp ◽

W.-Q. Chen ◽

R. E. Niks

Keyword(s):

Latent Period ◽

Recombinant Inbred ◽

Partial Resistance ◽

Recombinant Inbred Lines ◽

Inbred Lines ◽

Rust Fungi ◽

Puccinia Hordei ◽

High Level ◽

Early Abortion ◽

Two Populations

To elucidate the specificity of prehaustorial resistance to inappropriate rust fungi, we studied two populations of recombinant inbred lines of barley that segregated for partial resistance (PR) to Puccinia hordei and for the resistance to the inappropriate rust species P. recondita f. sp. tritici and P. hordei-murini. PR to P. hordei is prehaustorial and nonhypersensitive, and its level can be assessed accurately by measuring the latent period of the fungus. The resistance to the inappropriate rust species is a combination of prehaustorial (nonhypersensitive) and posthaustorial (hypersensitive) mechanisms. The amount of nonhypersensitive, early abortion of P. recondita f. sp. tritici and P. hordei-murini sporelings reflects the degree of prehaustorial defense to the two inappropriate rust species. All lines showing a long latent period of P. hordei also had a relatively high level of early abortion of the growth of P. recondita f. sp. tritici and P. hordei-murini. This indicates that genes for PR to P. hordei are also effective against these two inappropriate rust species. The reverse was not necessarily true; some lines showing a high level of early abortion of P. recondita f. sp. tritici and P. hordei-murini had a low level of PR to P. hordei. Moreover, lines with a similar level of prehaustorial resistance to P. recondita f. sp. tritici could differ considerably in their prehaustorial resistance to P. hordei-murini. This indicates that genes for prehaustorial resistance may exhibit rust species specificity.

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Diverse sources of resistance to Spodoptera litura (F.) in groundnut

Indian Journal of Genetics and Plant Breeding (The) ◽

10.31742/ijgpb.79s.1.8 ◽

2019 ◽

Vol 79 (01S) ◽

Author(s):

M. A. Saleem ◽

G. K. Naidu ◽

H. L. Nadaf ◽

P. S. Tippannavar

Keyword(s):

Recombinant Inbred ◽

Spodoptera Litura ◽

Hot Spot ◽

Recombinant Inbred Lines ◽

Insect Pest ◽

Inbred Lines ◽

Leaf Damage ◽

Botanical Variety ◽

Resistant Genotypes ◽

Botanical Varieties

Spodoptera litura an important insect pest of groundnut causes yield loss up to 71% in India. Though many effective chemicals are available to control Spodoptera, host plant resistance is the most desirable, economic and eco-friendly strategy. In the present study, groundnut mini core (184), recombinant inbred lines (318) and elite genotypes (44) were studied for their reaction to Spodoptera litura under hot spot location at Dharwad. Heritable component of variation existed for resistance to Spodoptera in groundnut mini core, recombinant inbred lines and elite genotypes indicating scope for selection of Spodoptera resistant genotypes. Only 29 (15%) genotypes belonging to hypogaea, fastigiata and hirsuta botanical varieties under mini core set, 15 transgressive segregants belonging to fastigiata botanical variety among 318 recombinant inbred lines and three genotypes belonging to hypogaea and fastigiata botanical varieties under elite genotypes showed resistance to Spodoptera litura with less than 10% leaf damage. Negative correlation existed between resistance to Spodoptera and days to 50 per cent flowering indicating late maturing nature of resistant genotypes. Eight resistant genotypes (ICG 862, ICG 928, ICG 76, ICG 2777, ICG 5016, ICG 12276, ICG 4412 and ICG 9905) under hypogaea botanical variety also had significantly higher pod yield. These diverse genotypes could serve as potential donors for incorporation of Spodoptera resistance in groundnut.

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