Progeny mean, heterosis and heterobeltiosis inSolanum tuberosum x tuberosum andS. tuberosum x andigena families under a short day sub-tropic environment

Abstract

SummarySolanum tuberosum x tuberosum (TxT) families were compared with S. tuberosum x andigena (TxA) families as progeny mean, heterosis and heterobeltiosis for ten important agronomic characters by evaluating 72 cross combinations (36 of TAT and 36 of T• from 18 common female parents), for three successive seedling and clonal generations under short day sub-tropic conditions. TxA families had more vigorous progenies, higher tuber yield, higher number of tubers, larger tubers and better general impression than TxT families. The TxA families were inferior to the T'ZI" families for characters such as tuber colour and uniformity of tuber colour, but their progeny means were within the acceptable range. High progeny means of TxA families were associated with high heterosis and high heterobeltiosis in these families, although there were a few exceptions. High mean performance for tuber yield and tuber number were associated with high variance of these traits in TxA families. It is concluded that, unlike under long day environments, andigena adapted to short days can be used advantageously for exploiting heterosis in the potato breeding programmes of short day subtropic environments.

Usefulness of Andigena (Solanum Tuberosum SSP. Andigena) Genotypes as Parents in Breeding Early Bulking Potato Cultivars

“…This is in agreement with earlier studies (Glendenning, 1969(Glendenning, , 1975Cubillos & Plaisted, 1976;Tarn & Tai, 1977, 1983Gopal et al, 2000). Significantly high heterosis for tuber number is in agreement with earlier studies (Tarn & Tai, 1977;Gopal et al, 2000). For average tuber weight heterosis in T × A families was not significantly better than that of T × T families.…”

“…For average tuber weight heterosis in T × A families was not significantly better than that of T × T families. Gopal et al (2000) reported significantly high heterosis for average tuber weight in T × A families as compared to intra-Tuberosum families in first clonal generation, while it was not significantly higher in second clonal generation.…”

“…In the present study average tuber weight, tuber number and yield did not differ significantly in T × T and T × A families. Superiority of T × A families over T × T families for yield as well as its components tuber number and average tuber weight was reported (Cubillos & Plaisted, 1976;Gopal et al, 2000) meaning thereby that better yield of T × A families in their studies were due to multiplicative interaction resulting from union of more tuber number and large tuber size. Tarn and Tai (1983) reported that T × A families were superior to T × T families for yield and tuber number but possessed reduced tuber size.…”

Genetic base of Indian potato selections as revealed by pedigree analysis

“…MS90-512 × 94P60) may lead to highly heterozygous populations for practicing selection of superior clones. Heterozygosity in potato is known to be essential to realize heterosis for economic characters like tuber yield (Cubillos & Plaisted, 1976;Sanford & Hanneman, 1982;Gopal et al, 2000). Selection of genetically diverse parents based on pedigree information in order to obtain transgressive segregates has been found to be effective in oats Cowen & Frey, 1987;Souza & Sorells, 1991), soyabean (Cox et al, 1985), cotton (Marani & Avieli, 1973), alfalfa (Sriwatanaponge & Wilsie, 1968), rapeseed (Lefort-Bunson et al, 1986), maize (Paterniani & Lonnquist, 1963) and wheat (Fonesca & Patternson, 1968).…”

“…The genetic diversity among the current selections as revealed by their pedigree analysis can be used to mate diverse clones for broadening the genetic base of the future selections as well to conserve the adaptive gene complexes. The potential to broaden the genetic base of Indian potato cultivars and also to realize heterosis for tuber yield and its components (Gopal et al, 2000) is immense considering that only 49 ancestors appeared in the pedigrees of 77 selections, whereas Indian germplasm collection has more than 1000 elite parental lines/cultivars and more than 800 andigena clones from 30 countries (Gopal and Gaur, 1997).…”