Breeding for Pepper yellow mosaic virus resistance and agronomic attributes in recombinant inbred lines of chili pepper (Capsicum baccatum L.) using mixed models

Phytophthora blight of vegetables caused by Phytophthora capsici causes significant economic losses in production of Solanaceae and Cucurbitaceae crops in Mexico. The development of universal resistant chili pepper cultivars is challenging due to the diverse virulence phenotypes produced by P. capsici. The objective of the study was to characterize the diversity of phenotypic interactions for P. capsici isolates recovered from production fields in Michoacán, Mexico, to facilitate the development of resistant cultivars. Virulence phenotypes were characterized for 12 isolates of P. capsici using 26 Capsicum annuum New Mexico Recombinant Inbred Lines (NMRILs) in greenhouse conditions. Criollo de Morelos CM-334 and California Wonder were used as resistant and susceptible controls, respectively. Seedlings at the four to eight true leaf stage were inoculated with 10,000 zoospores per seedling and disease severity was evaluated at 20 days post-inoculation. Two of the P. capsici isolates did not infect any pepper host even though the isolate was less than a year old. The 10 virulent isolates were designated in 10 virulence phenotypes. The information generated by this study is of utmost importance for efforts of producing resistant cultivars specific for Michoacán producers.

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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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