Effective selection criteria for screening drought tolerant recombinant inbred lines of sunflower

In this study, seventy two sunflower recombinant inbred lines were tested for their yielding ability under both water-stressed and well-watered states. The inbred lines were evaluated in a rectangular 8?9 lattice design with two replications in both well-watered and water-stressed conditions, separately. Eight drought tolerance indices including stability tolerance index (STI), mean productivity (MP), geometric mean productivity (GMP), harmonic mean (HM), stress susceptibility index (SSI), tolerance index (TOL), yield index (YI) and yield stability index (YSI) were calculated based on grain yield for every genotype. Results showed the highest values of mean productivity (MP) index, geometric mean productivity (GMP), yield index (YI), harmonic mean (HM) and stress tolerance index (STI) indices for ?C134a? inbred line and least values of stress susceptibility index (SSI) and tolerance (TOL) for C61 inbred line. According to correlation of indices with yield performance under both drought stress and non-stress states and principle component analysis, indices including HM, MP, GMP and STI could properly distinguish drought tolerant sunflower inbred lines with high yield performance under both states. Cluster analysis of inbred lines using Ys, Yp and eight indices, categorized them into four groups including 19, 6, 26 and 19 inbred lines.

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Inheritance of Rust Resistance, Yield Performance in Irrigated Condition and Identification of High Yielding Rust Resistant Recombinant Inbred Lines in Lentil

International Journal of Current Microbiology and Applied Sciences ◽

10.20546/ijcmas.2020.902.272 ◽

2020 ◽

Vol 9 (2) ◽

pp. 2393-2399

Author(s):

Alok Kumar ◽

Ranjit Kaur Gill

Keyword(s):

Recombinant Inbred ◽

Rust Resistance ◽

Recombinant Inbred Lines ◽

Inbred Lines ◽

Yield Performance ◽

Inheritance Of Rust Resistance

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Selection indices to identify maize (Zea mays L.) hybrids adapted under drought-stress and drought-free conditions in a tropical climate

Crop and Pasture Science ◽

10.1071/cp16141 ◽

2016 ◽

Vol 67 (10) ◽

pp. 1087 ◽

Cited By ~ 6

Author(s):

Bhupender Kumar ◽

Satish Kumar Guleria ◽

Subhash M. Khanorkar ◽

Rajender Babu Dubey ◽

Jashvantlal Patel ◽

...

Keyword(s):

Zea Mays ◽

Drought Stress ◽

Grain Yield ◽

Zea Mays L ◽

Tolerance Index ◽

Yield Performance ◽

Susceptibility Index ◽

Drought Tolerant ◽

Selection Indices ◽

Stress Susceptibility

Drought stress is the most important production constraint in maize (Zea mays L.), especially in rainfed agriculture. To improve productivity of rainfed maize, the development of hybrids with tolerance to drought stress is an important objective in maize breeding programs. The present study was undertaken to identify maize hybrids that perform better under drought-stress and drought-free conditions by using various selection indices. These selection indices were calculated on the basis of yield (t ha–1) performance of hybrids measured under drought stress and optimum environments. A set of 38 cultivars was evaluated at 10 environments (representing five each of drought stress and optimum growing conditions). The average reduction in grain yield due to drought stress was 52%. Effects of genotype, environment and their interaction were significant sources of variation in determining grain yield, respectively explaining 5.0–7.4%, 55.0–60.2% and 12.0–15.0% of total variation in yield under drought-stress and drought-free conditions. Of eight selection indices considered for study, three indices such as harmonic mean, geometric mean, and stress tolerance index were identified as suitable for selection of genotypes capable of performing well both under drought-stress and drought-free environments. Drought response index and drought resistance index were found useful in identifying hybrids that performed better under drought stress. Stress susceptibility index was negatively correlated with yield measured under drought stress. Stress susceptibility index could be used as selection index but only in combination with yield performance data under water-deficit conditions in order to identify drought-tolerant hybrids with reasonable productivity. Test weight, shelling percentage, days to maturity, and ear girth were found to be useful traits for improving yield performance across diverse environments. Cultivation of identified drought-tolerant hybrids would be useful to enhance maize productivity in drought-stress environments.

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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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