Overcoming crossing barriers between nontuber-bearing and tuber-bearing Solanum species: towards potato germplasm enhancement with a broad spectrum of solanaceous genetic resources

Genome ◽  
1995 ◽  
Vol 38 (1) ◽  
pp. 27-35 ◽  
Author(s):  
K. N. Watanabe ◽  
M. Orrillo ◽  
S. Vega ◽  
J. P. T. Valkonen ◽  
E. Pehu ◽  
...  

The first direct sexual hybrids between diploid nontuber-bearing species and diploid potato breeding lines are reported here. Three nontuberous species of Solanum, S. brevidens, S. etuberosum, and S. fernandezianum, were used for sexual crosses, achieved by a combination of rescue pollinations and embryo rescue. Initial hybrid selection was made using an embryo spot marker, followed by the evaluation of morphological and reproductive traits. Putative hybrids were first tested for resistance to potato leaf roll virus derived from the wild species, and then were tested with molecular markers using species-specific DNA probes. Finally, the tuberization of several 2x hybrids was tested for actual potato germplasm enhancement. These hybrids are unique in terms of their potential to enhance recombination between chromosomes of wild species and those of cultivated potatoes in germplasm utilization, and to exploit the genetic nature of tuber formation. The finding that nontuber-bearing Solanum spp. can be directly crossed with tuber-bearing species also has important implications for the regulatory aspects of the use of genetically modified organisms.Key words: nontuber-bearing Solanum, potato germplasm enhancement, interspecific crosses, chromosome manipulation, inter-EBN crosses, diploid.

Genome ◽  
1992 ◽  
Vol 35 (1) ◽  
pp. 53-57 ◽  
Author(s):  
Kazuo Watanabe ◽  
Carlos Arbizu ◽  
P. E. Schmiediche

The wild potato species Solanum acaule (acl) was used as a model of a disomic tetraploid Solanum species to develop systematic methods of germplasm enhancement for disomic tetraploid species. The objective was to develop a genetically efficient method to overcome the inherent technical problems encountered in the utilization of disomic tetraploid wild species. Accessions of acl were selected from CIP's wild germplasm collection and from the collection of University of Birmingham, with emphasis on genetic attributes such as PLRV resistance and (or) PSTV resistance. Four methods were tested: (i) triploids from crosses between 4x acl × 2x potato were selected for 2n gametes production and were crossed to tetraploids or to diploids with 2n egg production; (ii) axillary buds of triploid hybrids were treated with colchicine to double chromosome numbers to generate hexaploids; (iii) in vitro chromosome doubling to obtain hexaploids from triploid hybrids; and furthermore (iv) the selected acl clones were directly crossed to tetraploid potatoes followed by a combination of second compatible pollinations with IvP 35 and subsequent embryo rescue. The combination of second compatible pollination and embryo rescue was found to be the most genetically efficient method for the utilization of the valuable genetic attributes of acl.Key words: inter-EBN crosses, ploidy manipulation, polyploid, potato breeding, wild species


2004 ◽  
Vol 31 (2) ◽  
pp. 65-70 ◽  
Author(s):  
W. F. Anderson ◽  
G. Kochert ◽  
C. C. Holbrook ◽  
H. T. Stalker

Abstract Peanut breeders are constantly in search of new sources of genes that confer tolerance or resistance to biotic and abiotic stresses to improve the production and quality. The objective of this study was to evaluate peanut lines generated from interspecific crosses for amounts of wild species introgression, including genes for resistance to peanut root-knot nematodes, tomato spotted wilt virus and leaf spot diseases. Nine diploid Arachis species were crossed with peanut breeding lines and 130 different interspecific hybrid lines were developed. These lines were evaluated for the amount of introgression using RFLP analyses, plant morphology, and disease resistant phenotypes. Based on RFLPs, 41 lines showed measurable introgression and 12 hexaploid-derived lines were polymorphic for at least four probes. Greenhouse and field evaluations indicated that resistance was not present in the lines tested for tomato spotted wilt virus, early leaf spot, or Cylindrocladium black rot. However, resistance approaching that of the wild species was found for the peanut root-knot nematode (Meloidogyne arenaria) among lines derived from crosses with Arachis diogoi, A. correntina, A. batizocoi, and A. cardenasii. Introgression lines were resistant (disease ratings of 1.5 to 4.5 and lesion numbers 8 to 63) compared to Southern Runner (ratings of 5.5 to 6 and lesion numbers of nearly 500) for late leaf spot (Cercosporidium personation) in field evaluations performed in Gainesville, FL over 2 yr. The greatest resistance was found among lines from crosses with A. batizocoi, A. duranensis, A. stenosperma, A. magma, and A. diogoi. Results indicate that it should be possible to identify molecular markers to tag resistance genes for use in conventional breeding programs and stack these genes in highly productive peanut cultivars.


2020 ◽  
Vol 9 (1) ◽  
pp. 15-19
Author(s):  
Waqas Ashraf ◽  
Amer Habib ◽  
Muhammad Ahmad Zeshan ◽  
Amina Amin ◽  
Safdar Ali ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document