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1.
Summary Two crosses of sorghum, Sorghum bicolor (L.) Moench (IS 1054 × ICSV-1, and IS 5604 × IS 1054) were evaluated in parental, F1, F2, and backcross generations for the variation in their popping quality as measured by pop volume (ml). Dominance was in the direction of low pop volume. Dominance and additive gene effects, in that order, governed most of the variation, while significant dominance x dominance type of interaction effects could also be detected. There was no evidence for higher order gene interactions.Approved as Journal Article 630 by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, P.O. 502 324, Andhra Pradesh, India. 相似文献
2.
Summary The occurrence of seed malformation in association with reduced thousand grain weight and germination ability has been observed in crosses between cultivated female plants and wild male plants. A survey of 16 cultivated accessions (P. glaucum subsp. glaucum) and 11 wild accessions (P. glaucum subsp. monodii) ranging over the whole species diversity showed this postzygotic incompatibility was general, but its intensity varied greatly with the cultivated female accession used and very little with the wild male parent origin. About 15% of the 123 cultivated x wild crosses observed gave normal seeds. Seed malformation has never been observed in crosses between cultivated accessions and appeared independent of genetic distances between the parents. The reciprocal crosses between wild female plants and cultivated male plants gave normal-looking seeds with good germination but consistently reduced thousand grain weight. Both seed malformation and seed small size are an expression of a genetic imbalance. These slight reproductive barriers seem to have been built during the domestication process.Abbreviation ICRISAT
International Crop Research Institute for the Semi-Arid Tropics 相似文献
3.
Summary Triple test cross-analysis was used to detect epistasis in chickpea. None of the characters investigated exhibited epistasis. In the absence of epistasis, additive and dominance effects were estimated. The results indicated the importance of additive genetic variance for seed yield, biological yield, number of primary branches, number of secondary branches, 100-seed weight, days to flower, and number of seeds per pod; dominance genetic variance for days to mature; and both additive and dominance genetic variances for plant height. Selection methods, such as pedigree and bulk, are suggested for the improvement of most characters.Joint contribution from ICARDA, P.O. Box 5466, Aleppo, Syria and ICRISAT (International Crops Research Institute for the Semi-Arid Tropics), Patancheru P.O. 502 324, A.P., India. 相似文献
4.
Summary Natural out-crossing imposes considerable costs and inefficiencies in breeding, evaluation and commercialization of pigeonpea (Cajanus cajan (L.) Millsp.). This note reports identification of a modification of floral morphology which inhibits cross-fertilization. Floral morphology and possible mechanisms of action of this character are discussed.On leave from International Crops Research Institute for the Semi-Arid Tropics (ICRISAT). Hyderabad, India. 相似文献
5.
Summary The chick pea germplasm collection maintained at ICRISAT Center, Patancheru, India, is the largest collection of this crop available in one place. This collection was grown in instalments and described for qualitative and agronomical traits. The importance and distribution of six qualitative traits, namely flower colour, plant colour, growth habit, seed shape, seed surface and seed colour have been discussed.Approved as J. A. No. 365 by the International Crops Research Institute for the Semi-Arid Tropics (ICRI-SAT). 相似文献
6.
Summary The development of the pollen mother cells (PMC's) and anther wall of a male-sterile mutant was microscopically compared with that of fertile sib plants in pigeon pea (Cajanus cajan). Male-sterility was complete and caused by breakdown of microsporogenesis at prophase I. Delayed and incomplete development of the anther wall appeared to be responsible for PMC degeneration. The sterile mutant also differed from the fertile plants in the size and number of the PMC's.On leave from International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Hyderabad, India. 相似文献
7.
Summary Commonly the chickpea leaf is uni-imparipinnate, having 9–15 leaflets. However, certain variants have been reported; these are available in the chickpea collection at ICRISAT and were re-examined. Based on the lamina differentiation, three major classes of leaf type can be recognized: uni-imparipinnate (normal), multipinnate and simple (leaf). (Certain other leaf forms reported earlier are not classes of leaf type though they are distinct variants). It was determined that the leaf type differences are governed by two genes (mlsl), which show supplementary gene action. The multipinnate leaf is formed when the first gene is dominant (ml+sl/.sl). Whereas the simple leaf occurs when the first gene is recessive and the second gene is in either form (ml./ml.), the normal leaf is expressed when both dominant genes are present (ml+sl+/..).Submitted as J.A. No. 814 by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT). 相似文献
8.
Summary Knowledge of inheritance of early maturity or its components is important to groundnut breeders in developing short-duration cultivars. This study was conducted to determine the inheritance of two components of early maturity: days to first flower from sowing, and days to accumulation of 25 flowers from the appearance of first flower, using three groundnut genotypes. Two early-maturing (Chico and Gangapuri) and one late-maturing (M 13) genotypes were crossed in all possible combinations, including reciprocals. The parents, F1, F2, F3, and backcross populations were evaluated for days to first flower from sowing, and for days to accumulation of 25 flowers. The data suggest that days to first flower in the crosses studied is governed by a single gene with additive gene action. Chico and Gangapuri possess the same allele for this component of earliness. Three independent genes with complete dominance at each locus appear to control the days to accumulation of 25 flowers. In crosses between late (M 13) and early (Chico or Gangapuri) parents, a segregation pattern suggesting dominant-recessive epistasis (13 late:3 early) was observed for this component. Segregation in the F2 generation (1 late:15 early) of both early parents (Chico x Gangapuri) indicated that the genes for early accumulation of flowers in these two parents are at different loci.Submitted as ICRISAT J.A. No. 1557. 相似文献
9.
Summary The short note describes the morphology and chromosome number of Cicer canariense Santos Guerra & Lewis. This taxon has been found to have a meiotic chromosome number of 2n<16 and not 2n<24, as reported earlier. At ICRISAT Center, while other perennial Cicers did not perform well, Cicer canariense flowered and produced seeds. The species grew vigorously and had multi-podded peduncles and multi-seeded pods. Such traits of Cicer canariense can be very useful in the genetic improvement of chickpeas.Submitted as JA 1456 by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT). 相似文献
10.
Summary To determine the distribution and geographic specificity of sterility maintainers in pearl millet, Pennisetum americanum (L.) Leeke, 428 diverse pearl millet germplasm accessions representing variation from 12 countries were crossed with a male-sterile line 5141A. The F1 hybrids were classified as male-fertile or male-sterile based on the seed set on bagged ear heads and an other morphology. Among these, 87 (20.3%) were classified as male-fertile, 32 (7.5%) as male-sterile, 282 (65.9%) as segregating for male-fertile/male-sterile and 27 (6.3%) behaved as male-fertile in the rainy and male-sterile in the postrainy season. Restorer lines were distributed in all the countries studied except Cameroon and USSR. Maintainer lines were observed from six countries but were concentrated in India. These maintainer lines differ from one another in several morphological and agronomic characters such as flowering, plant height, spike length and grain size. They may prove to be useful sources of material for generating new male-sterile lines. The restorers can be used to produce commercial hybrids.Submitted as J.A. No. 719 by the International Crops Research Institute for the Semi-Arid Topics (ICRISAT). 相似文献
11.
New sources of resistance of cowpea (Vigna unguiculata) toStriga gesnerioides,a parasitic angiosperm
T. H. M. Moore J. A. Lane D. V. Child G. M. Arnold J. A. Bailey G. Hoffmann 《Euphytica》1995,84(3):165-174
Summary Thirty-seven accessions of cowpea and yard-long bean were assessed for resistance toStriga gesnerioides. Cowpea plants were grown using anin vitro method, then inoculated with young seedlings ofS. gesnerioides produced from seed from three West African countries. Resistance was assessed by comparing the number and size ofS. gesnerioides tubercles on these accessions with those on a known susceptible cowpea, cv. Blackeye. Two cowpea landraces, APL-1 and 87-2, were completely resistant toS. gesnerioides from Burkina Faso, Mali and Cameroon and partially resistant toS. gesnerioides from Niger. Complete resistance was expressed either as a hypersensitive response of infected root tissues or as a severely retarded development of successful infections. All other accessions, including three samples of yard-long bean were susceptible toS. gesnerioides. The original 87-2 plants segregated for resistance and susceptibility. However, uniformly resistant progeny were obtained by producing seed from vegetatively propagated clones of single resistant 87-2 plants. Resistance of APL-1 and 87-2 toS. gesnerioides was confirmed in pot and field trials. Neither of these cowpeas were resistant toAlectra vogelii. Varieties APL-1 and 87-2 provide additional sources of resistance to most races ofS. gesnerioides, including a newly discovered virulent race from Benin.Abbreviations ICRISAT
International Crops Research Institute for the Semi-Arid Tropics
- IITA
International Institute of Tropical Agriculture
- SAFGRAD
Semi-Arid Food Grain Research and Development 相似文献
12.
Summary A d2 dwarfing gene in pearl millet [Pennisetum glaucum (L.) R. Br.] is currently being extensively used for the development of hybrid parents. Its effect on grain yield and yield components is poorly understood. Twelve pairs of tall and dwarf near-isogenic lines developed in the diverse genetic background of three composites were evaluated for grain yield and yield components for 2 years at two locations in southern India. The d2 gene or the genes linked to it, on an average, reduced plant height by 42%, grain yield by 14%, and head girth by 8% but increased head length and number of tillers per plant by about 5–6%. Large variations were observed among pairs (genetic background) for the difference between tall and dwarf near-isogenic lines for all of the above yield components resulting in no significant difference in five pairs and 17–35% less yield in dwarfs as compared to their tall counterparts in six pairs. Days to 50% flowering and seed weight were least affected by the d2 gene with the average difference between tall and dwarf groups of near-isogenic lines being of the order of 1–2%. These results indicate that the advantageous effects of d2 dwarfing gene can be effectively exploited by manipulating the genetic background. The difference between the average grain yields of tall and dwarf groups of near-isogenic lines showed considerable variation across environments with the dwarfs yielding as much as tall group in one environment and up to 30% less than the tall group in the other, thus, indicating that the d2 gene effect may be substantially modified by the environments.Submitted as JA No. 979 by the International Crop Research Institute for the Semi-Arid Tropics (ICRISAT). 相似文献
13.
A study was made on the inheritance of seed weight of tomato, and on the effect of seed weight on growth of tomato plants. Use was made of 15 parental genotypes and 105 F1s produced by diallel crossing (F1-seeds). From combining ability analysis of variance carried out for weight of F1-seeds it appeared that the weight of seeds harvested from tomato plants was mainly determined by the maternal genotype and largely independent of the genotype of the male parent. A combining ability analysis of variance for weight of seeds produced by seilfing F1's (F2-seeds) showed, however, that female and male parents contributed equally to the inheritance of seed weight and that the inheritance of seed weight is determined mainly by chromosomal additiveiy acting factors, but that also non-additive gene action occurred. Genotypes with large seeds produced heavier seedlings than genotypes with small seeds, In later growth stages, the correlation between seed weight and plant weight became smaller, presumably, due to a lower relative growth rate of the seedlings from large seeds. For this reason, it is doubtful whether breeding of large seeded tomato cultivars opens up prospects of improving growth and yield of tomato plants. 相似文献
14.
Inheritance of stalk rot resistance in cauliflower (Brassica oleracea var. Botrytis L.) 总被引：2，自引：0，他引：2
Summary The inheritance of resistance in cauliflower to stalk rot (Sclerotinia sclerotiorum (Lib.) de Bary) was investigated in population from six generations of six crosses. Disease incidence was recorded on 4 parents, 6 Fs
1, 6 Fs
2 and 12 back-crosses in a screenhouse under artificially created epiphytotic conditions. Resistance to stalk rot in this set of parents was found to be polygenic and under the control of recessive genes and due primarily to additive gene action. A breeding strategy emphasizing recurrent selection should lead to improvement in resistance. 相似文献
15.
The inheritance of testa (seed coat) colour and interaction of cotyledon and testa colours were studied in seven crosses of
lentil (Lens culinaris Medik.) involving parents with black, brown, tan or green testa and with orange, yellow or dark green cotyledons. Analysis
of F2 and F3 seed harvested from F1 and F2 plants, respectively, revealed that although black testa is dominant over nonblack testa, its penetrance is not complete
since both F1 plants and heterozygous F2 plants produced varying proportions of seeds with either black or nonblack testa. The F2 populations of the crosses between parents with brown and tan, as well as brown and green, testa segregated in the ratio
of 3 brown : 1 tan and 3 brown : 1 green, respectively, indicating monogenic dominance of brown testa colour over tan or green.
The expression of testa colour was influenced by cotyledon colour when parents with brown or green testa are crossed with
those having orange or green cotyledons. Thus F2 seeds from these crosses with a green testa always had green cotyledons and never orange cotyledons. F2 seeds from these crosses with a brown testa always had orange cotyledons and never green cotyledons. These results suggest
diffusion of a soluble pigment from the cotyledons to the testa.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
16.
Summary Yield and yield components of F1 hybrids were studied in three experiments at 30×30 cm spacings and in one experiment at 15×15 cm spacings. In the 30×30 cm experiments, 10 of the 41 hybrids tested significantly outyielded their high parents. However, only 2 hybrids significantly outyielded the best cultivar: one hybrid yielded 23 % and the other 16 % more than their respective check cultivars. The four hybrids in the 15×15 cm experiment yielded only 59 to 92% as much as their high parents.In areas where rice is transplanted at relatively wide spacings, the observed levels of F1 heterosis in selected hybrids may be sufficient to warrant production of hybrid rice, if enough hybrid seed can be produced. For direct-seeding at the high rates normal in the USA, the relatively small levels of heterosis and the difficulties of hybrid seed production preclude use of F1 hybrid rice cultivars at present.None of 19 bulk F2 and F3 hybrids in two experiments yielded significantly more than its high parent. Similarly, none of the 12 mixtures included in one experiment yielded significantly more than its high parent. On the basis of yield alone, using bulk F2 or F3 or simple mixture populations is not merited.Contribution from the Western Region, Agricultural Research Service, U.S. Department of Agriculture, and the Department of Agronomy and Range Science, University of California, Davis, California 95616. 相似文献
17.
K. B. Saxena L. Singh M. V. Reddy U. Singh S. S. Lateef S. B. Sharma P. Remanandan 《Euphytica》1990,49(3):185-191
Summary
Atylosia scarabaeoides (L.) Benth., a wild relative of pigeonpea, possesses several useful genes which can be utilized for pigeonpea improvement. In the present study, 33 accessions of A. scarabaeoides were evaluated at ICRISAT Center during the 1987 rainy season for variation in some useful traits to identify parents for inter-generic hybridization. A large variation was observed for leaf components, seed size, pod length, seeds/pod, days to flowering, seed protein, sulphur amino acids, resistance to cyst nematode, phytophthora blight, sterility mosaic, fusarium wilt, pod borer, pod fly, and pod wasp. Only four accessions were found to have more than 28% protein content. Methionine and cystine contents were marginally higher than in pigeonpea but the variation was not large enough to utilize them in the breeding program. In A. scarabaeoides. accessions resistant to fusarium wilt, phytophthora blight, sterility mosaic, and cyst nematode were detected. Compared to pigeonpea, the A. scarabaeoides accessions were less susceptible to lepidopteran borer and were immune to pod fly damage. Accessions ICPW 89 and ICPW 111 in short- (100–120 days), and ICPW 94 and ICPW 118 in medium-duration (140–180 days) were identified as potential parents for use in inter-generic hybridization.ICRISAT Journal Article No. 967 相似文献
18.
Summary The character of determinate plant growth has not been reported for chickpea and has not been observed in the world germplasm collection at ICRISAT, Patancheru, India. A determinate growth habit would be desirable where growing conditions often lead to excessive vegetative growth. We attempted to generate this trait by mutation breeding. Seeds of the cultivar ICCV 6 were exposed to varying irradiation treatments, M1 and M2 populations were raised, and in the latter one plant was detected that showed the determinate growth habit and female sterility. The character of determinate growth segregated in a postulated digenic epistatic 3:13 fashion in the F2 and confirmed its digenic mode of inheritance in the F3 and F4. The symbol cd is proposed for the allele conditioning for determinancy and Dt for the allele expressing the determinate trait. Continued mutation breeding with this and other material may result in identifying fully fertile, determinate plant types.Abbreviations DT -
determinate
- IDT -
indeterminate
ICRISAT Journal Article No. 1396. 相似文献
19.
Summary Crosses between an early flowering inbred broccoli (Brassica oleracea L. var. italica) HS140 and four later maturing inbred lines, S301, S310, s318, and S258, were studied to determine the inheritance of earliness as expressed by days to first open flower. Mean days to first flower for F1 and F2 were almost identical, and were close to the mean of the two parents in three crosses, indicating additive inheritance. In the cross HS140×S258, for which no F1 plants were available, the F2 mean was closer to the mean of the early parent, but this was likely due to a distortion of the data caused by the very late maturation of S258, the latest maturing parent in the study. Frequency distribution for parents and progenies supported the conclusions from parent and progeny mean values and indicated that days to maturity is a quantitative character, with mostly additive inheritance.Oregon Agricultural Experiment Station Technical Paper No. 7578. 相似文献
20.
Combining ability of seed vigor and seed yield in soybean 总被引：4，自引：0，他引：4
Studies have shown no consensus in relationships between seed yield and vigor in soybean [Glycine max (L.) Merrill]. The lack of information regarding the inheritance of seed vigor prompted this study to determine the types
of gene action and combining ability estimates for seed vigor and its related traits. Five high and six low seed vigor soybean
genotypes were crossed in a diallel, and selfed to produce 55 F2 progenies, which were examined, along with the parents, for seed vigor, yield, and seed weight. Significant genotype and
environment effects were found for seed vigor and yield. General combining ability (GCA) effects for seed vigor and seed yield
were significant (p≤ 0.01) and larger than specific combining ability (SCA) effects. Significant GCA and SCA effects were found for seed weight,
indicating that both additive and non additive genetic effects were involved in conditioning seed weight. The ratios of mean
square, 2GCA / (2GCA+SCA), were 0.96 for seed vigor and 0.93 for seed yield. These ratios indicated that additive gene effects
were more important than non additive gene effects for seed vigor and seed yield in these crosses. Mean seed vigor(83.8%),
as determined by accelerated aging germination, and mean seed yield (2,155 kg ha-1)in high vigor × high vigor crosses were higher than the high vigor × low vigor and low vigor × low vigor crosses. Mean percent
accelerated aging germination rates in F2 populations from diallel crosses were significantly related to mid-parent seed vigor(r2 = 0.52**) and midparent seed size (r2 = 0.31**). These results indicated that levels of seed vigor can be improved through breeding, while maintaining high yields because
of the predominance of GCA effects in both seed vigor and seed yield.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献