Genetical analysis of male-sterility in carrots, Daucus carota L.

Abstract

1.A genetical analysis of male-sterility in carrots was made in one set of Fr's and in two sets of backcrosses. 2. The individual ratios were checked on binomial probability paper of MOSTELLER and TUKEY. In addition groups of ratios produced by crossing one male-sterile plant to various male-fertiles, or various male-steriles to one male fertile, were compared to backcross ratios as a further check. 3. Eight different hypotheses were tested. The hypothesis that male-sterility in carrots is controlled by a cytoplasmic factor, two duplicate nuclear genes (one recessive, one dominant), and two complimentary dominant fertility restoring nuclear genes, proved satisfactory. CONTENTS

The Influence of Flower Structures on the Seeds Productivity of the Carrot Breeding Lines

“…Thus, even if the umbels of the first three orders were sterile, reversion to fertility in the subsequent orders could be observed. It seems to be similar as described by Banga et al (1964), Chadha & Frese (1981) or Struckmeyer & Simon (1986). That is the reason why anther-like structures in the flowers with distinctive filaments required special, penetrating microscopic observations and staining with aceto-orcein, which enable verification of the presence of sporogenic tissue (Fig.…”

“…For many years plants with cytoplasmatic male-sterility trait (CMS) have been used as a mother form in F 1 hybrid breeding, including carrot (Banga et al 1964, Erickson et al 1982, Nothnagel et al 2000. The absence of anthers excludes pollen production and it is direct reason why the type of male-sterility where anthers transform into petals (petaloid sterility) is safer and more often used by breeders than brown-anther sterility (Chadha & Frese 1981, Morelock et al 1996.…”

Effect of Agronomic Practices and Weed Management Practices on Weed Dry Weight and Weed Control Efficiency in Direct Seeded Rice under Rainfed Condition of Eastern Uttar Pradesh

“…Globally, total rice consumption was recorded 477.4 million metric tonnes in 2013-14 (Anonymous, 2015). It is grown on approximately 163 m ha out of which 145 m ha is in Asia (Anonymous, 2013). Ninety per cent of the world's rice is produced as well as consumed in Asia (Solunke et al, 2006).…”

Flower development in carrot CMS plants: mitochondria affect the expression of MADS box genes homologous to GLOBOSA and DEFICIENS

“…Petals have sepaloid features (Kitagawa et al ., 1994) and stamens are converted into either petals (‘petaloid’‐type) or carpel‐like structures (‘carpeloid’‐type), respectively. The ‘petaloid’ CMS system of carrot is well characterised at the genetic level (Banga et al ., 1964; Börner et al ., 1995; Thompson, 1961; Welch and Grimball, 1947; Wolyn and Chahal, 1998). A single dominant gene (M) and two homozygous recessive alleles (ll,tt) are proposed to maintain male sterility.…”