Research using wild relatives of the soybean, such as Glycine falcata Benth., a native of Australia, has been hampered by an extremely low seed set under greenhouse conditions in the absence of pollinating vectors. A quick and efficient method of enhancing seed set in this species was developed in working with Neonotonia verdcourtii, a species from Africa formerly included in the...
The Spl locus (Orf and Hymowitz, 1976; Gorman and Kiang, 1978) codes for beta-amylase (Hildebrand and Hymowitz, 1980). Two mobility variants and two null variants have been described (Orf and Hymowitz, 1976; Kiang, 1981). We have been conducting a survey of isoenzyme variability in the soybean genn-plasm collections.
Genetic type T218M was found in 'Illini
A single Mendelian locus has been described (Devine, 1984) that condi-tions ineffective vs. effective nodulation response upon inoculation of soy-bean lines withRhizobium fredii (Scholla and Elkan, 1984). A formal gene sym-bol has not been assigned to this locus; for convenience, we will refer to it here as Rj?. In a breeding program with a long-term goal of developing adapted...
Soybean plants homozygous for the male-sterile mutation ms4 are capable of seed production in the absence of insect pollinators (Graybosch and Palmer, 1984). Cytological investigations have demonstrated the genesis of pollen grains by male-sterile plants at a frequency of 3.3% (Graybosch and Palmer, 1985). Pollen formed is identical to that of male-fertile plants, and will...
Five different populations have been recognized as sources of ms1 alleles. Genetic studies of male-sterile, female-fertile mutations conducted by Palmer et al. (1978) showed that ms1-North Carolina (T260), ms1-Urbana (T266), ms1-Tonica (T267), and ms1-Ames (T268) are independent mutations at the ms1 locus. Yee and Jian (1983) reported another mutation at the ms1 locus, designated...
The gene-for-gene hypothesis has been found applicable to several host-parasite interactions in which the parasite is a fungus. It has most satisfactorily explained interactions involving cereal rust and powdery mildew diseases in which cases the pathogens are obligate parasites and the genes of both the parasites and hosts may be manipulated in genetic tests. Generally, the gene...
Several genes conditioning resistance to SMV have been found and some have been assigned gene symbols. In addition, a series of SMV strain groups has been differentiated by their interactions with a selected group of culti-vars (Cho and Goodman, 1979; Lim, 1985). We have undertaken a study of the genes conditioning the reactions of certain differential cultivars to SMV in an...
With the discovery of soybean cyst nematode (SCN) in the U.S. in 1954, the research for resistance was initiated. Ross and Brim (1957) identified several soybean plant introductions resistant to the North Carolina SCN populations. Epps and Hartwig (1972) reported PI lines resistant to race 4.
Several years ago, we identified seven plant introductions resistant to the 16 races of Phytophthora megasperma f. sp. glycinea Kuan and Erwin (Pmg) known at that time. Each of these was crossed to the eight cultivars in Table 1 to determine how resistance was controlled. They were not crossed to cultivars that contained Rps2 or Rps5 because Rps2 was found using root inoculation...
Fusarium wilt of soybean (causal organism: Fusarium oxysporum Schlecht. emend. Snyd. & Hans.) has become an increasingly severe disease in the breed-ing plots at Gainesville and may be an undiagnosed or misdiagnosed problem in soybean production fields. At Gainesville, severity of Fusarium wilt, or a complex which includes F. oxysporum, has reduced yields in some plots to near-ly...
Metribuzin [4-amino-6-tert-butyl-3-(methylthio)-as-triazin-5(4H)-one] is an herbicide that can be effective in controlling many broadleaf weeds in soybeans. However, some soybean cultivars are sensitive to metribuzin and can suffer considerable damage (Wax et al., 1976). Previous research has established that a single recessive gene, hm, conditions the sensitive reaction of 'Semmes
At the Asian Vegetable Research and Development Center, developing improved vegetable soybeans is one of the objectives. In accomplishing that objective, one of the crosses involved AGS 188, PI 157424 from Maturity Group IV and G 10381, cultivar 'Kaohsiung
Obtaining intervarietal hybrids of Glycine max (L.) Merrill in a cool climate such as in Poland (latitude above 50°N) is one of the most important problems for development and introduction of original cultivars of this species. In 1977, hybrid soybean seeds were obtained for the first time in our Academy through field crossing of various forms (cultivars and PI's). Charac...
The existence of an interdependence between some important traits of soy-bean is of great significance for its breeding. In rather cool climate (Poland) interdependences between developmental traits and yield structure elements affect the possibility of fast creation and introduction of new, well-adapted and efficient cultivars into agricul-tural practice. Estimation of...
Abstract: Interrelationships among different characters were determined by simple correlations and path-coefficient analysis using 36 diverse and elite cultivars representing different geographical origin. The results revealed a highly significant positive association of the branches per plant and pods per plant with grain yield. The pods per plant also showed a high direct...
In spite of high yielding ability of Birsa Soybean-1 for the plateau re-gion of Bihar, it has not become popular among the farmers because of its black seed-coat color. The seeds of Birsa Soybean-1 were irradiated with different doses of gamma rays at FCI Sindri, Bihar (India) in 1979. Proge-nies of a yellow-seeded 50 Kr. M-2 plant in M-3 gave very promising and inter-esting...
Soybean is generally cultivated in India as a sole or monoculture crop. However, its intercropping with maize is a common practice in some hilly areas of northern India. The practice aims at (1) insuring against total crop fail-ures under abnormal weather conditions, (2) increasing total productivity for unit land area, and (3) equitable and judicious utilization of land...
Abstract : Experiment carried out with different materials for two years revealed the beneficial effects of mulching on seedling emergence as well as yield. The average increase in seedling emergence over control (no mulching) was 97.3, 53.1, 35.7, and 28.6% in plots mulched with paddy straw, wheat straw, paddy husk, and wheat husk, respectively. Mulching with paddy straw and...
Introduction: The concept of foliar nutrition and its relationship with yield is not new. Nutrients, especially the micronutrients when applied as foliar spray, exert pronounced influence on plant growth and yield. Such micronutrients are in use for improving the growth and yield of crops.
Breeding programs with primary emphasis on yield and resistance to dis-eases are in progress at this center since 1967-68. Rapid strides have since been made in this direction with breeding and release of several high-yield-ing soybean varieties, viz: Ankur, Alankar, Shilajeet, PK-262, PK-327, PK-308, and PK-416. However, still a constraint to expansion of soybean cultivation in...
In 1984, parents, F1, F2, and F3 populations of three crosses of Glycine max x G. soja, G. max x G. gracilis and G. max x G. max had been planted simultaneously for comparison of the inheritance of several agronomic charac-ters of the above three different soybean crossing combinations. Performance of lines or cultivars of different species used as parents can be shown in Table 1...
The identity of Rps alleles and loci conferring resistance to phytoph-thora root rot can ordinarily be determined by means of a hypocotyl screening procedure. However, if more than one Rps allele pair is included in a line, allele identification by this procedure can be very difficult. Several soybean/phytophthora breeding programs are including two or three Rps allele pairs in...
Researchers investigating isozymes in soybeans have employed both starch gel and polyacrylamide starch gel (PAGE) electrophoretic systems. Unfortunate-ly, the banding patterns that have been observed when each of these gel systems is histochemically stained for a given isozyme can be quite different. Most of the genetic work that has been done on soybean isozymes has been done on...