Interspecific hybrid of Helianthus annuus × H. simulans: Characterization and utilization in improvement of cultivated sunflower (H. annuus L.)

Common sunflower (i.e., Helianthus annuus) is occasionally crossed with other Helianthus species to gain favourable agronomic traits. An interspecific cross between H. annuus and Helianthus mollis was used to examine events that occurred during the five first generations. First generation hybrid plants were verified using GISH, and F 1 hybrid (#17) was back-crossed to common sunflower to obtain BC 1 (#4) and BC 2 (#21). Some BC 2 progeny possessed new traits, i.e., compact (Compact plant architecture is due to short inter-node length, short petiole length and short leaf lamina length) architecture without and with corrugated leaves, which were not observed in the parents. These traits were selected for and fixed after the BC 2 -S 3 (#18) to produce a H. mollis introgression line (namely HM374). Although the size of the population was small, we tentatively construct a genetic map using data from the BC 2 generation. Two linkage groups were identified carrying H. mollis specific AFLP markers that were associated with compact plant architecture, and one unlinked marker was shown to explain variation for the corrugated leaves. Introgression line HM374 was used to test the inheritance of compact plant architecture in a cross with an elite high oleic line, OL75HO. Microsatellite (SSR) markers were used to genotype F 1 and F 2 offspring's. Our data suggested that the line HM374 was still heterozygous for introgression after eight generations. HM374 displays new architecture traits (i.e. compact architecture with or without corrugated leaves) and carries H. mollis fragments anchored on LG1 and LG11 of sunflower public map.

Section: Cytogenetic Analysesmentioning

confidence: 99%

Transfer of architectural traits from perennial Helianthus mollis Lam. to sunflower (H. annuus L.) and localisation of introgression

Breton

Gil²,

Wargnier

et al. 2012

“…The heritability of the resistance trait has been proved through identification of resistance sources in H. argophyllus derivatives. Hybrids of cultivated sunflower with diploid perennials and tetraploid species are difficult to be obtained through traditional crosses but can be recovered through embryo rescue techniques and amphidiploidization methods (Espinasse et al 1991;Atlagic et al 1995;Prabakaran and Sujatha 2004). Thus, there lies vast scope for exploitation of wild sunflowers with different mechanisms of resistance to enhance the level and diversify the basis of resistance to S. litura in cultivated sunflower.…”

Section: Discussionmentioning

confidence: 99%

Resistance to Spodoptera litura (Fabr.) in Helianthus species and backcross derived inbred lines from crosses involving diploid species

Sujatha

Lakshminarayana

2006

Self Cite

Spodoptera litura (Fabr.), the tobacco caterpillar, is a major defoliator on sunflower in the tropics. Genetic variability for resistance to S. litura is limited in the cultivar germplasm of sunflower. In the present investigation, 43 accessions of 17 wild Helianthus species of the annual and perennial habit groups were evaluated along with cultivated sunflower under field and no-choice conditions in the laboratory for resistance to this pest. Under field conditions, H. occidentalis and H. argophyllus were found to be immune with no leaf damage and few accessions of the species belonging to section Divaricati were found to be resistant. Laboratory bioassays against neonate, two and 4-day-old larvae confirmed resistance both in terms of high larval mortality and low larval weight gain in eight species viz., H. occidentalis, H. argophyllus, H. tuberosus, H. maximiliani, H. mollis, H. simulans, H. divaricatus and H. hirsutus. Intra-accessional variability was observed and accessions of few species showed varied reaction (resistant, partially resistant to susceptible) to the target pest. Field evaluation of 224 backcross derived inbred lines from five cross combinations involving diploid species under high natural pest incidence revealed low damage in plants derived from crosses involving H. argophyllus and H. petiolaris.

“…Since the seed set was very less the resultant single BC 1 F 1 plant was propagated through tissue culture using nodal explants as described for wild sunflowers and interspecific hybrids (Sujatha and Prabakaran 1997;Prabakaran and Sujatha 2004).…”

Section: Backcrosses and Propagation Through Tissue Culturementioning

confidence: 99%

“…Conventional crosses with the species belonging to the secondary gene pool are hindered by structural heterozygosity, genome size differences and incompatibility. However, we reported introgression of resistance from a diploid perennial species, H. simulans into sunflower by overcoming the problem of hybrid sterility by resorting to the technique of in vitro colchiploidy (Prabakaran and Sujatha 2004). Interspecific hybrids with other diploid perennials, which are sources of resistance to A. helianthi have been produced but met with partial success while utilizing in resistance breeding programmes (Atlagic et al 1995;Nikolova and Christov 1996;Faure et al 2002).…”

Section: Introductionmentioning

confidence: 99%

Ploidy Manipulation and Introgression of Resistance to Alternaria Helianthi from Wild Hexaploid Helianthus Species to Cultivated Sunflower (H. annuus L.) Aided by Anther Culture

Sujatha

Prabakaran

2006

Self Cite

The present investigation discusses the scope for transferring of resistance to leaf spot disease incited by Alternaria helianthi from two hexaploid wild species (H. tuberosus and H. resinosus) to diploid cultivated sunflower. Interspecific hybrids produced between sunflower and these two hexaploid species were partially fertile with tetraploid chromosome status. Backcrosses of these interspecific hybrids with cultivated sunflower resulted in the formation of sterile triploid plants. To overcome the problem of sterility and facilitate backcrosses with cultivated sunflower, anther culture of the tetraploid interspecific hybrids was carried out to bring down their chromosome number to diploid status. Anthers from both interspecific hybrids were cultured on basal Murashige and Skoog media supplemented with varying concentrations of organics and the growth regulators benzyladenine and naphthaleneacetic acid. Anthers of interspecific hybrids involving H. resinosus responded well and regenerated through an embryogenic route at a frequency of 98.7%. But in interspecific hybrids with H. tuberosus, anthers formed callus and subsequently regenerated shoots through an organogenic pathway. DNA ploidy analysis of anther culture plants of interspecific hybrids derived from H. tuberosus crosses was carried out to identify plants with desired diploid status. In vitro screening of parents, interspecific hybrids and anther culture plantlets against A. helianthi showed resistance in 68.5% of the anther culture plants of interspecific hybrids from H. tuberosus and in 24.3% of the plants derived from interspecific hybrids involving H. resinosus.