That root system architecture (RSA) has an essential role in nitrogen acquisition is expected in maize, but the genetic relationship between RSA and nitrogen use efficiency (NUE) traits remains to be elucidated. Here, the genetic basis of RSA and NUE traits was investigated in maize using a recombination inbred line population that was derived from two lines contrasted for both traits. Under hi...

Genotyping by sequencing (GBS) provides opportunities to generate high-resolution genetic maps at a low genotyping cost, but for highly heterozygous species, missing data and heterozygote undercalling complicate the creation of GBS genetic maps. To overcome these issues, we developed a publicly available, modular approach called HetMappS, which functions independently of parental genotypes and ...

A number of S male-sterile plants from several shrunken-2 inbred lines were crossed initially with an R138-TR inbred line pollinator carrying the nonrestoring genotype for S sterile cytoplasm. One such cross, involving a male-sterile female parent from inbred line M825, produced, unexpectedly, a number of male-fertile F(1) progeny, along with the expected male-sterile off-spring. Pollen records...

specific chromosome regions (Mock, 1972). The discordant results found by different investigators for the same Recombination values in plants are influenced by genetic factors, chromosome region may be attributed to genotype 3 environmental conditions, and their interactions. In soybean, Glycine environment interaction, chromosome structure differmax (L.) Merr., the cosegregation method to prod...

The development of maize foundation parents is an important part of genetics and breeding research, and applying new genetic information to produce foundation parents has been challenging. In this study, we focused on quantitative trait loci (QTLs) and general combining ability (GCA) of Ye478, a widely used foundation parent in China. We developed three sets of populations for QTL mapping and t...

Transgressive segregation in cotton (Gossypium spp.) provides an important approach to enhance resistance to the major pest root-knot nematode (RKN) Meloidogyne incognita. Our previous studies reported transgressive RKN resistance in an intraspecific Gossypium hirsutum resistant NemX × susceptible SJ-2 recombinant inbred line (RIL) population and early generations of interspecific cross Gossypi...

N TESTCROSSES it is commonly supposed that each recombination I offspring owes its phenotype to chiasmata in a single primary oocyte which gives rise to no other offspring. This assumption should be questioned in view of the demonstration that crossing over may be induced by X rays in oogonial cells of Drosophila melanogaster ( WHITTINGHILL 1938). Irradiation is known to increase the percentage...

The pitch canker fungus Fusarium circinatum was first associated with mortality of P. radiata in California during the 1980s. Since then it has been dispersed to several countries of the Northern hemisphere together with South Africa and Chile in the southern hemisphere. In Chile the disease caused mortality of seedlings in P. radiata at nursery, and in South Africa the pathogen has already com...

HE term “aberrant segregation” is used here to include any prezygotic Tphenomenon which causes production of uneven numbers of either of the two sexes or the two classes of progeny from a testcross. Such phenomena have been referred to as “drive” and if a meiotic mechanism is the cause, “meiotic drive” (SANDLER and NOVITSKI 1957; NOVITSKI and HANKS 1961). DUNN (1953) originally discussed the im...