Purpose

Large quantities of byproducts are produced from beet sugar industry causing deleterious environmental pollution. This study aimed to evaluate the surface and foliar application of molasses and vinasses as an eco-innovative amendment and nutritional supplements on sugar beet yield and quality.

Methods

The yield and root juice quality of two sugar beet varieties were evaluated for two growing seasons under nine fertilization and soil amendment application treatments.

Results

Application of molasses to the soil has significantly promoted root yield, with the highest root yield resulting from the application of 360 L ha⁻¹ of molasses to the soil. Likewise, the highest values of sucrose content, quality index (QZ)%, recoverable sugar (RS) % and recoverable sugar yield were produced from the application of 360 L ha⁻¹ of molasses. Moreover, the lowest Na%, K% and α-amino N% values in both varieties resulted from the surface application of 360 L ha⁻¹ molasses. Compared to the control treatment, applying 360 L ha⁻¹ of molasses improved the available N, P and K as well as the organic matter, calcium and magnesium contents in the soil.

Conclusions

Beet sugar molasses could be applied to the soil surface as a soil amendment and a substitute for the application of inorganic nitrogen and phosphorus fertilizers. Molasses is a promising eco-friendly soil amendment that greatly enhances sugar beet productivity and biofortification by improving the physical and chemical properties of the soil.

Sweet potato (Ipomoea batatas L.) originated from South America; therefore, it is vulnerable to low temperature. Here, the evolutionary analysis of 22 cold-responsive genes in 35 plant species revealed that the identified MYC-type basic helix-loop-helix (bHLH) transcription factors exhibit diverse structures. We found that the number of bHLH gene family members was significantly lower than that of cold-tolerant species. We further systematically evaluated the gene structure, promoter analysis, synteny analysis, and expression pattern of 28 bHLH gene family members in sweet potato. The basic helix-loop-helix protein 116 (IbbHLH116) has the closest phylogeny to the AtICE1 protein of A. thaliana. However, the IbbHLH116 protein from cold-tolerant variety FS18 showed a 37.90% of sequence homology with AtICE1 protein. Subcellular localization analysis showed that IbbHLH116 is localized in the nucleus. The transcripts of IbbHLH116 were highly accumulated in cold-tolerant genotype FS18, particularly in new leaves and stems, compared to the cold-sensitive genotype NC1 under cold stress. Overexpression of IbbHLH116 in the wild type (Col-0) A. thaliana significantly enhanced cold tolerance in transgenic plants by regulating activities of oxidative protective enzymes, such as peroxidase (POD), superoxide dismutase (SOD), and the contents of malondialdehyde (MDA), proline and soluble proteins. Moreover, overexpression of IbbHLH116 in ice1 mutant A. thaliana fully rescued the cold-sensitive phenotype by promoting the expression of C-repeat binding factors 3 (CBF3). Overexpression of IbbHLH116 in the sweet potato callus also induced the expression of CBF3 under low temperature. These results imply that IbbHLH116 can perform the function of the ICE1 gene in conferring cold tolerance in sweet potato.

Although the genotypic variation of nutrient use efficiency of bread wheat has been a focus of many previous studies, this variation may largely depend on the growth environment and the range of wheat cultivars being investigated. The present study aimed to examine the influence of the growth environment on the genotypic variation of nutrient use efficiency of wheat, the relationship between nutrient use efficiency parameters and yield or grain quality, and the changes in nutrient use efficiency parameters with wheat breeding history. We conducted a two-year field experiment at four different sites, and the genotypic variation of 12 nitrogen (N), phosphorus (P) and potassium (K) use efficiency parameters (NUE, PUE and KUE) were investigated in a large wheat diversity panel composed of 437 wheat cultivars released over more than 150 years. Compared with previous reports, our study expanded the lower limits of the ranges of nutrient use efficiency parameters. The NUE parameters were strongly positively correlated with the corresponding PUE parameters. Yield showed significant positive genetic correlations with most nutrient use efficiency parameters and was more strongly correlated with nutrient uptake efficiency. There was no significant genetic correlation between NUE, PUE or KUE with grain N concentration. Compared to tall cultivars, semi-dwarf wheat cultivars had higher P, K harvest index, N, K grain production efficiency. N harvest index, N, P uptake efficiency of the semi-dwarf cultivars slowly increased along with breeding history, and the relationships with breeding history for other parameters are largely environmental dependent. In conclusion, the greater genotypic variation of nutrient use efficiency of wheat revealed in our study provides insights into the improvement of nutrient-efficient wheat cultivar breeding. NUE and PUE could be improved simultaneously through wheat breeding. The nutrient harvest index, nutrient uptake and grain production efficiency could be target traits for nutrient-efficient wheat cultivar breeding.

This study analyzes dynamic changes in fossil energy input, energy output and fossil energy use efficiency in crop production in Hunan province, China, from 2010 to 2019 to determine the factors contributing to fossil energy use efficiency in crop production. The results showed that energy input decreased from 19.98 to 18.13 GJ ha-1 from 2010 to 2019, whereas energy output increased from 64.57 to 69.57 GJ ha-1. Energy use efficiency was estimated at 3.23 in 2010 and increased to 3.84 in 2019. The application of fertilizers (nitrogen and phosphorus) and pesticides was decreased, while the application of compound fertilizers was increased from 1.00 to 1.43 GJ ha-1 with a steady energy input during the study period. The yield of advantageous industry crops in Hunan province (cereals, oil-bearing crops, vegetables and fruits) was increased, while other crops (fiber crops, beans, sugarcane, tubers, tobacco and cotton) showed an indiscernible pattern. Our results indicate that developing countries need to promote the production and application of compound fertilizers to reduce energy input, develop competitive industries to increase energy output, adopt policies to optimize crop production structure and establish sustainable agricultural production systems.

Maize is an important feed and industrial cereal crop and is crucial for global food security. The development of drought-tolerant genotypes is a major aim of breeding programs to fight water scarcity and maintain sustainable maize production. Late embryogenesis abundant (LEA) proteins are a family of proteins related to osmotic regulation that widely exist in organisms. Here, we implemented a previously generated maize transcriptomic dataset to identify a drought-responsive gene designated ZmNHL1. Bioinformatics analysis of ZmNHL1 showed that the protein encoded by ZmNHL1 belongs to the LEA-2 protein family. Tissue specific expression analysis showed that ZmNHL1 is relatively abundant in stems and leaves, highly expressed in tassels and only slightly expressed in roots, pollens and ears. Moreover, the activity of SOD and POD of plants from three 35S::ZmNHL1 transgenic lines under either the …