Authors:W.T. Xue, A. Gianinetti, R. Wang, Z.J. Zhan, J. Yan, Y. Jiang, T. Fahima, G. Zhao, and J.P. Cheng
Crop seeds are the main staples in human diet, especially in undeveloped countries. In any case, the diet needs to be rich not only in macro-nutrients like carbohydrates and protein, but also in micro-nutrients. Nevertheless, both the macro- and micro-nutrients presented in seeds largely vary in consequence of field and environment conditions. In this research, 60 lines of a barley RILs population segregating for the SSR marker Hvm74, which is genetically linked to the GPC (grain protein content) locus (HvNAM-1), were studied in 4 environments (two growing years and two field managements) by carrying out a comprehensive profile of seed macro- (starch, total nitrogen and total soluble protein) and micro-nutrients (phytate, phenolics, flavonoids, Pi, Zn and Fe). Under field conditions, all the components were largely affected by the environment, but TN (total nitrogen) exhibited high genotype contribution, while micro-nutrients displayed higher genotype × environments interactions (GEI) than macro-nutrients. In order to approach the effects of carbon-nitrogen (C–N) balance on other seed components, two C/N ratios were calculated: C/TN (CNR1) and C/TSP (CNR2). CNR2 exhibited stronger negative correlations with all micro-nutrients. Hence, the significant GEI and its negative relationships with CNR2 highlighted the different characters of micro-nutrients in barley seeds.
Authors:G.C. Zhou, H.C. Shi, X.J. Yu, J.C. Yuan, Q. Guo, C.Y. Zhao, Q. Sun, and Y.P. Ke
Male sterile mutants play an important role in the utilisation of crop heterosis. Male sterile plants were found in S5 generations of maize hybrid ZH2, through continuous sib-mating by using the fertile plants in the same population, we obtained a male sterile sibling population K932MS including sterile plants K932S and a fertile plant K932F. The objective of this study was to clarify the genetic characterisation and abortion characteristics by nucleus and cytoplasm effect analyses, cytoplasm grouping, and cytological observation. The results showed that no difference was found between K932S and K932F in the vegetative growth stage, but K932S had no emerging anther or pollen grains. The segregation ratio of fertile plants to sterile plants was 1:1 in the sibling progenies, while it was 3:1 in self-crossing progenies of K932F. The sterility of K932S could be restored among reciprocal progenies when seven normal inbred lines were used as females respectively. The fertility expression of K932S crossed with 30 testers would be changed in different test-crosses and some backcross progenies. The C-type restorer Zifeng-1 (Rf4Rf4) was able to restore the fertility of K932S, and the specific PCR amplification bands of K932MS were consistent with CMSCMo17. The anther of K932S began abortion at dyad with its tapetum expanded radically and vacuolated: this induced abnormality in the shapes of both dyads and tetrads. The microspore could not develop normally, and then it collapsed and gradually disappeared. Hence, K932MS is a C-type cytoplasmic male sterile mutant with a pollen-free, stable inheritance: it has potential application value for further research.
Authors:F. Xu, L. Sun, P. Chen, Y. Qi, J. Zhang, J. Zhao, Y. Liu, L. Zhang, Zhong Cao, D. Yang, J. Zeng, and Y. Du
The heat capacities of LiNH2 and Li2MgN2H2 were measured by a modulated differential scanning calorimetry (MDSC) over the temperature range from 223 to 473 K for the
first time. The value of heat capacity of LiNH2 is bigger than that of Li2MgN2H2 from 223 to 473 K. The thermodynamic parameters such as enthalpy (H–H298.15) and entropy (S–S298.15) versus 298.15 K were calculated based on the above heat capacities. The thermal stabilities of them were investigated by
thermogravimetric analysis (TG) at a heating rate of 10 K min−1 with Ar gas flow rate of 30 mL min−1 from room temperature to 1,080 K. TG curves showed that the thermal decomposition of them occurred in two stages. The order
of thermal stability of them is: Li2MgN2H2 > LiNH2. The results indicate that addition of Mg increases the thermal stability of Li–N–H system and decrease the value of heat
capacities of Li–N–H system.