Analysis on the Breeding and Major Traits of Wide-adaptability Indica CMS Line Yungu 3A

Breeding sterile lines is the key to the development of hybrid rice with wide adaptability. However, at present, few wide-adaptability sterile lines have been applied in production practice. In this study, Yungu 3A, a new WA-type Indica CMS line with good grain quality, was developed by hybridization between Yunfeng 66A with wide adaptability as female parent and F1 plants of Yunfeng 66B/D62B as male parent and continuous backcrossing. According to the results, the finally obtained lndica CMS line Yungu 3A has good plant type and leaf shape, strong tillering ability, excellent flowering habit, stable and complete male sterility with the sterile plant rate and pollen sterility rate of 100%, strong combining ability, high outcrossing rate, low sensitivity to light and temperature, and strong disease resistance, which was approved by Yunnan Provincial Crop Variety Appraisal Committee in 2013. Yungu 3A is conducive to the development of new hybrid rice combinations with good quality and wide adaptability, exhibiting a promising prospect of application.

Alternative kind of hydrogen atoms as a possible explanation for the latest puzzling observation of the 21 cm radio line from the early Universe

There is a puzzling astrophysical result concerning the latest observation of the absorption profile of the redshifted radio line 21 cm from the early Universe(as described in Bowman et al.). The amplitude of the profile was more than a factor of two greater than the largest predictions. This could mean that the primordial hydrogen gas was much cooler than expected. Some explanations in the literature suggested a possible cooling of baryons either by unspecified dark matter particles or by some exotic dark matter particles with a charge a million times smaller than the electron charge. Other explanations required an additional radio background. In the present paper, we entertain a possible different explanation for the above puzzling observational result: the explanation is based on the alternative kind of hydrogen atoms(AKHA),whose existence was previously demonstrated theoretically, as well as by the analysis of atomic experiments. Namely, the AKHA are expected to decouple from the cosmic microwave background(CMB) much earlier(in the course of the Universe expansion) than usual hydrogen atoms, so that the AKHA temperature is significantly lower than that of usual hydrogen atoms. This seems to lower the excitation(spin) temperature of the hyperfine doublet(responsible for the 21 cm line) sufficiently enough for explaining the above puzzling observational result. This possible explanation appears to be more specific and natural than the previous possible explanations. Further observational studies of the redshifted 21 cm radio line from the early Universe could help to verify which explanation is the most relevant.