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Granule size distribution of wheat starch is an important characteristic that could affect the functionality of wheat (Triticum aestivum L.) products. Lodging is a major limiting factor for wheat production. Few studies have been conducted to clarify how lodging influences the granule size distribution and viscosity parameters of starch in wheat grains. Two growing seasons, two high-yield winter wheat cultivars, and five artificial lodging treatments were imposed. The results indicated that lodging significantly reduced the content of starch and increased that of protein. Additionally, lodging caused a marked drop in both starch and protein yields. The relative loss of grain yield, starch yield, harvest index, and protein yield all differed remarkably among lodging treatments with a ranking of L2 > L1 > L4 > L3. Lodging also led to a reduction in the proportion (both by volume and by surface area) of B-type granules and a corresponding increase in that of A-type granules, and the more serious the lodging degree, the greater effect on the changes in these proportions. The smaller starch granules predominated in number, even though their collective contribution to the overall volume is was relatively minor. Meanwhile, it was found that the peak viscosity, hold viscosity, final viscosity, breakdown viscosity, and rebound value of wheat starch were significantly decreased by lodging. Correlation analysis showed that the peak and final viscosities were negatively correlated with volume percentages of A-type starch granules, but were positively correlated with B-type granules. This indicates that B-type granules have higher peak and final viscosities compared with A-type granules in wheat kernels. Lodging can reduce the proportion of B-type starch granules, and thus reduce the peak and the final viscosity in wheat grain. [ABSTRACT FROM AUTHOR]

In the context of the increasingly serious issues of resource waste, soil degradation, and environmental pollution caused by excessive nitrogen fertilizer application worldwide, this study conducted a two-year field experiment in Qinghai Province to explore suitable nitrogen fertilizer management strategies for the region. Ten fertilization levels were set, incorporating varying ratios of conventional nitrogen fertilizer and organic fertilizer, as well as the proportion of base fertilizer and topdressing. The focus was on monitoring the forage yield, quality, and related physiological indicators of oats during the flowering and milk stages. The use of correlation analysis and the multi-criteria decision-making model TOPSIS was applied for comprehensive data evaluation to determine the optimal fertilization strategy. After systematic data collection and analysis, the results showed that when 75% conventional nitrogen fertilizer was combined with 4500 kg·hm−2 of organic fertilizer (F4), the oat yield during the milking stage reached its peak at 14,722.48 kg·hm−2. Additionally, the yield effect was optimal (13,677.34 kg·hm−2) when using 30% base fertilizer and 70% jointing fertilizer (D2). Regarding nutritional quality, the fertilization strategy combining 75% conventional nitrogen fertilizer with 4500 kg·hm−2 of organic fertilizer, along with 30% base fertilizer and 70% jointing fertilizer (F4D2), significantly reduced the content of acid detergent fiber (ADF), neutral detergent fiber (NDF), and coarse fiber (CF) in oats, while increasing the content of EE (crude fat) and CP (crude protein). This significantly improved the nutritional value of oats. Correlation analysis further revealed the positive effect of fertilization amount and fertilization period on oat yield, as well as a negative correlation with fiber content. Finally, through comprehensive evaluation using the multi-criteria decision-making model TOPSIS, we verified the superiority of the fertilization strategy. [ABSTRACT FROM AUTHOR]

The changes in biomass (including yield), copper (Cu) concentration, and the accumulation of wheat (Triticum aestivum. L) in response to soil Cu pollution under nighttime warming had still not been explored. Hence, this study was carried out, and these variations were analyzed from a physiological perspective. Pot trials were performed at two levels of ambient temperatures (no-warming (NT) and average nighttime warming of 0.28 °C (WT)) and two levels of soil Cu concentrations (control check without Cu application (CK) and 100 mg/kg Cu application (Cu)). Soil was collected from the carbonate cinnamon soil region of central China. The warming effects of the passive nighttime warming system were prominent, and the average increment was 0.28 °C. Antioxidant enzyme activities were promoted by warming (p < 0.05) and Cu. The highest yield was achieved in NT-Cu, mainly attributed to relatively strong root activity and photosynthesis caused by supplemental Cu, but the Cu concentration in its grains was close to the threshold (10 mg/kg) for Cu concentration in foodstuff and could present a potential food safety risk. Though nighttime warming did not increase the total biomass and yield of wheat, it decreased the Cu accumulation of wheat grown in Cu-contaminated soil, especially in grains. Moreover, WT-CK and WT-Cu increased the Cu concentration in the roots and glumes and reduced the Cu concentration in grains by 13.09% and 55.84%, respectively, probably because of a lower transpiration rate. Among them, the Cu concentration of grains in WT-Cu was the lowest and significantly lower than other applications. Our findings reveal that nighttime warming has the potential to reduce the Cu risk of grains in wheat grown in the Cu-contaminated carbonate cinnamon soil region of central China and could then provide a theoretical reference for risk assessment of food quality for wheat subjected to dual stress from nighttime warming and Cu pollution. [ABSTRACT FROM AUTHOR]

The ridge–furrow with plastic film mulching (RF) system has been widely adopted in rain-fed crop planting due to its potential to enhance crop yield and water use efficiency. However, the impact of the RF system on maize lodging resistance, particularly when nitrogen fertilizer is applied, remains uncertain. Therefore, a two-year field experiment was carried out with two planting systems (FP: flat planting and RF) and two nitrogen application rates (N180: 180 kg·N ha−1 and N300: 300 kg·N ha−1) to assess the risk of lodging in maize. The results showed that compared to FP, RF resulted in a significant increase of 78.7% in lodging rate. In addition, the lodging rate increased by 22.6% with increasing nitrogen fertilizer application. The lignin content increased by 43.4%, while the stalk bending strength rose by 42.5%, under RF compared to the FP system. These improvements in the mechanical properties of maize stalks contributed to the improved lodging resistance index of RF, which was found to be approximately 21.3% higher than that of FP. In addition, high nitrogen application rates increased the risk of lodging for different planting patterns over two years. In conclusion, fertilization of spring maize with 300 kg·N ha−1 under the RF system led to higher yields but increased lodging rates. The risk of lodging should be considered when planting maize under the RF system. The results of this study can provide scientific basis and technical support for the optimization of rain-fed maize cultivation measures in the Loess Plateau. [ABSTRACT FROM AUTHOR]

Sucrose phosphate synthase (SPS) is an important link in the process of sugar metabolism. In addition, it is also involved in abiotic stresses in plants. In order to study the SPS gene family and its role in abiotic stress, we identified the MdSPS gene family members by bioinformatics methods such as correlation analysis, the HMM method, and the Clustering method, and analyzed the transient expression of MdSPS genes by quantitative real-time fluorescence analysis (qRT-PCR). The MdSPS gene family consists of a total of 19 members divided into three subfamilies distributed on 14 chromosomes in apples. The MdSPS gene family has 12 collinearity gene pairs, indicating significant duplication. Most members of this family contain a large number of plant hormone response elements, light-inducible elements, and abiotic stress response elements 2kb upstream of the promoter. Codon bias analysis shows that there are 28 high-frequency codons and no codons with strong preference in this family. Gene chip results showed that only MdSPS2, MdSPS3, MdSPS11, and MdSPS17 were up-regulated in roots, and they were all members of subfamily C. The qRT-PCR analysis showed that all members of this family responded significantly to drought stress, salt stress, and low temperature stress. Interestingly, the relative expression of MdSPS12 was significantly down-regulated under salt stress and low temperature stress. In addition, the expression of MdSPS3, MdSPS8, MdSPS11, and MdSPS17 was more than 20 fold higher than that of the control under drought stress, salt stress, and low temperature stress. These four genes could be candidates for molecular breeding in the MdSPS family. [ABSTRACT FROM AUTHOR]

Tartary buckwheat is a cereal crop that has both medicinal and food origins. However, the underlying factors that contribute to Tartary buckwheat's flowering and seed-setting characteristics, effective grain formation, and physiological changes are still not well understood. This study aimed to investigate the flowering and seed-setting characteristics of different parts of Tartary buckwheat, as well as the grain-filling characteristics after flowering. To achieve this, Tartary buckwheat cultivars with high (QK3) and low (XQ2) seed-setting rates were selected for pot and field experiments. The study found that Tartary buckwheat undergoes flowering and seed setting simultaneously. Many wilted flowers and grains were observed 45 and 51 d after flowering. Compared to XQ2, QK3 exhibited a higher grain formation rate and seed-setting rate by 7.42% and 26.16%, respectively. Additionally, QK3 had a significantly lower grain abortion rate by 12.03%. The 1000-grain weight and average grain-filling rate of QK3 were 11.10% and 14.81% higher than those of XQ2, respectively. QK3 exhibited a faster maximum grain-filling rate (Rmax), reaching 18.38% faster than XQ2. Additionally, the dry matter average distribution rate in the main stem and branched grains of QK3 was 13.26% and 23.07% higher than that of XQ2, respectively. The sucrose concentration, SS, and SSS enzyme activities of QK3 were all higher than those of XQ2, by 0.29–25.99%, 5.22–11.62%, and 6.64–12.47%, respectively. Correlation analysis revealed a significant positive correlation between sucrose, soluble sugar, and starch concentration during the grain formation process and SS and SSS activities. This suggests that the levels of SS, SSS, soluble sugar, and sucrose in the grain play a crucial role in grain filling. [ABSTRACT FROM AUTHOR]

This study explored the effects of the sowing stage and nitrogen application rate on the grain yield and its allocation of light-temperature resources over a 9-year experiment from 2011 to 2019. Measurement indicators include the effective accumulative temperature on different growth durations, leaf area index (LAI), above-ground biomass production, and harvest index (HI). Methods: A split-plot design was arranged in the treatment, with N supply as the main plot and the sowing stage as the subplot. The main plots consisted of two nitrogen treatments: low nitrogen (LN: 120 kg ha−1) and high nitrogen (HN: 180 kg ha−1). The subplots contained two sowing stages: the early sowing stage (ES) and the late sowing stage (LS). Results: Compared with LNLS, LNES, and HNLS from 2011 to 2019, HNES of HHZ increased the grain yield by 9.5%, 2.5%, and 5.3%, while the difference in grain yield in YY8 was higher than HHZ, especially under HNES. Compared with LNLS, LNES, and HNLS from 2011 to 2019, HNES of HHZ increased the panicle number by 6.0%, 5.9%, and 1.0%, and HNES of YY8 increased by 12.7%, 11.4%, and 3.8%. Compared with HNLS of HHZ, LNES, LNLS, and HNES decreased the spikelets per panicle by 2.3%, 2.9%, and 1.1%, and decreased by 3.5%, 1.9%, and 2.2% in YY8. The early sowing or increasing N supply significantly increased the dry matter accumulated, grain weight, LAI, and HI. The higher grain yield in LNES was more closely related to the average temperature and the number of spikelets per panicle. The grain yield in HNES was more dependent on the effective accumulative temperature. Conclusions: Sowing in mid-May and increasing the N application (180 kg ha−1) are beneficial to the allocation of light temperature and the increase in yield. Therefore, this research provides a theoretical basis for improving rice yield and optimizing the utilization of light-temperature resources in the future. [ABSTRACT FROM AUTHOR]

The ridge–furrow planting pattern is an effective strategy to improve grain yield, and changes in the ridge and furrow microenvironments affect wheat yield. However, the mechanism by which wheat yields are increased at different ridge–furrow ratios is unclear. In this study, four planting modes, namely the traditional planting mode (M1) and ridge–furrow ratios of 50:50 cm (M2), 75:50 cm (M3), and 100:50 cm (M4), were established for wheat under field conditions from 2021 to 2023; the effects of different treatments on light energy utilization, dry matter accumulation and transport, and grain yield were studied. The findings demonstrated that the M3 treatment exhibited the highest enhancements in parameters such as leaf area index (LAI), canopy photosynthetically effective radiation interception rate, relative chlorophyll content (SPAD) index, and net photosynthetic rate. Moreover, the M3 treatment displayed superior grain filling compared to other treatments. The post-anthesis assimilate accumulation in the M3 treatment was 11.93%, 4.69%, and 13.13% higher than that of M1, M2, and M4 treatments, respectively, and the grain yield in M3 increased by 7.70–9.56%, 3.13–4.91%, and 8.69–10.90% compared with those in M1, M2, and M4 in the two growing seasons, respectively. In summary, under the conditions of this study, the M3 treatment led to higher LAI and SPAD values in flag leaves post-anthesis compared to the other treatments. Moreover, M3 optimized canopy structure, led to the highest canopy interception rate, and increased photosynthetic rates per individual plant. Consequently, there was a significant increase in post-anthesis dry matter accumulation, resulting in the highest grain yield achieved among the treatments. [ABSTRACT FROM AUTHOR]

High temperature has seriously impacted the production of wheat in many countries. We examined four wheat cultivars (PBW343, Berkurt, Janz, and Attila) under heat stress (35/25 °C) and control treatments (23/15 °C) for 3 days at the meiosis and anthesis stages to evaluate the response and recovery of the four cultivars to heat stress and the relationship between photosynthetic parameters related to heat tolerance. Photosynthetic activity in all cultivars declined in plants that were treated at 35 °C, even for only 1 d compared with control plants. However, the differences among the four cultivars were obvious in net photosynthetic rate (Pn). At meiosis, the reduction of Pn in Berkut and PBW343 was lower and could nearly fully recover after 3 d of recovery and showed higher heat tolerance characteristics. The highest reduction in Pn occurred in Janz, which did not recover completely after 3 d of recovery. The same trend was observed at the anthesis stage, but Pn in all cultivars could not fully recover. Taking transpiration rate (Tr), stomatal conductance (gs), intercellular CO2 concentration (Ci), and limitation of stomatal conductance (Ls) into account, results suggested the decline in Pn under heat stress was mainly caused by non-stomatal restriction. In parallel with the decline in Pn, the maximum photochemical efficiency (Fv/Fm) decreased. In addition, both the maximum rate of net photosynthesis (Pmax) and the light saturation point declined after heat stress in all cultivars. However, the relevant photosynthetic parameters of PBW343 and Berkut recovered more quickly at both the meiotic and flowering stages. In summary, there were significant differences in the adaptability of different cultivars to high temperatures, with Berkut and PBW343 being more adaptable to heat stress than Janz and Attila. These may be used as valuable resources for further studies in breeding to understand the physiological mechanisms of heat sensitivity. This paper provides detailed information on the ecophysiological responses of wheat under heat stress. [ABSTRACT FROM AUTHOR]

Nontarget-site resistance (NTSR) is a complex multigenic trait that is associated with the potential mechanisms of herbicide resistance which pose a serious threat to global crop protection. However, the NTSR mechanisms of Alopecurus japonicus, a malignant weed infesting wheat fields, are less characterized. In this study, we used RNA-sequencing transcriptome and enzyme activity detection to investigate the NTSR mechanisms and candidate genes involved in fenoxaprop-P-ethyl (FE) in a previously identified resistant population compared to the sensitive population of A. japonicus. Transcriptome analysis identified nine upregulated genes, which were constitutively overexpressed and upregulated by FE application in the resistant population, and the results were validated using quantitative real-time PCR. These genes including one cytochrome P450 monooxygenase (P450) gene (CYP75B4), one ATP-binding cassette (ABC) transporter gene (ABCG36), one laccase (LAC) gene (LAC15), one 9-cis-epoxycarotenoid dioxygenase (NCED) gene (NCED5), two purple acid phosphatase (PAP) genes (PAP4, PAP15), one sucrose phosphate synthase (SPS) gene (SPS3), one protein related to disease resistance gene (RGA3) and one immune protein gene (R1B-17). The activity assay of LAC, NCED, PAP and SPS revealed that the activities of these enzymes in the resistant population were significantly higher than those in the sensitive population at 0 h and after FE application at 12 h, 24 h and 72 h. Nevertheless, whether LAC, NCED, PAP and SPS genes were involved in herbicide metabolism needs to be further validated. Our results revealed that CYP, ABC transporter and LAC genes may participate in A. japonicus resistance. These genes identified in the present study provide new insights into the resistance mechanism of weeds in response to herbicide. Our study also implies the complexity of the NTSR mechanisms of weeds. [ABSTRACT FROM AUTHOR]

Codonopsis pilosula is a medicinal and edible herb with a rich nutritional value. In Gansu Province, China, its production quality and yield differ during the four seasons. Here, we investigated the differences in the microfloral composition and metabolic functions in the rhizospheric soil and roots of C. pilosula during the four seasons, and we also analyzed their dynamic and synergistic effects on C. pilosula growth and carbohydrate content change. The C. pilosula samples were analyzed for plant physiology, microfloral composition and metabolic functions in the rhizospheric soil and roots using high-throughput sequencing technology. Environmental indices including soil physiochemistry and meteorological conditions were also determined by the coupled chromatography–spectroscopy technique. The results revealed that the C. pilosula growth was affected by temperature, precipitation and light intensity, with the bacterial structures and functions of the soil and root samples showing obvious seasonal changes. Due to the diversity of microbial composition and community metabolic function, and the synergistic effect of microbial and environmental factors, there are significant differences in stress resistance, physiological status and metabolites of C. pilosula in different seasons. Furthermore, the change in seasons was significantly correlated with the quality and yield of C. pilosula. This study provides a scientific basis for soil improvement and the refinement of local Radix C. pilosula cultivation methods. [ABSTRACT FROM AUTHOR]

Early heat and drought priming may increase the plant's ability to resist later drought and heat stress. However, it remains unclear whether combined heat and drought priming can enhance the acclimation of plants to later combined stress by improving physiological activities. In this study, maize seedlings were first pre-exposed twice to heat, drought, and a combination of stresses followed by recovery, and then subjected to six days of more severe stresses. A considerable reduction in photosynthetic pigment content, stomatal size, and photosynthesis was observed under heat and drought conditions, and the changes in the above indicators were amplified under combined stress conditions. Stress priming improves antioxidant defense and cellular osmoregulation, as indicated by improved superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), glutathione reductase (GR), and ascorbate peroxidase activities, as well as elevated soluble sugar (SS) and proline (Pro) contents. Lower superoxide anion and malondialdehyde contents and injury index in the primed seedlings demonstrated the mitigation of oxidative stress. ROC analysis revealed that SOD and POD had considerable reliability in determining that maize seedlings were experiencing heat stress (AUC = 0.941–0.971); GR and SS were capable of accurately monitoring drought stress that was being experienced by plants (AUC = 0.919–0.958); and SOD, GR, and Pro had more capability for detecting the combination of heat and drought stress (AUC = 0.907–0.958). Collectively, the primed seedlings exhibited better performance than the non-primed seedlings, exhibiting stronger stress acclimation supported by an effective antioxidant defense system and osmoregulatory function. [ABSTRACT FROM AUTHOR]

Dryland winter wheat (Triticum aestivum L.) production plays an extremely important role in the southeast of the Loess Plateau. Planting patterns have great influence on improving soil water storage and yield, and should be matched with different seeding rates. In order to assess the effect of different sowing methods on the drought resistance and stable yield of dryland wheat, a field experiment was conducted in Wenxi County Dryland Wheat Experimental Base in Shanxi Province, China. In the current study, the effects of three planting techniques (drilling sowing, furrow sowing, and film-mulched sowing) and four seeding rates (150, 225, 300, and 375 kg ha−1) were examined on water storage, dry matter formation, yield, and water use efficiency (WUE). The results showed that furrow sowing (FS) and film-mulched sowing (FM) treatments increased soil water storage in the 0–300 cm soil layer at overwintering and jointing stages. In addition, FS and FM increased soil water consumption in the 0–300 cm soil layer from overwintering to maturity of wheat. Furthermore, FS and FM significantly increased the dry matter accumulation from the overwintering to the mature stage, promoted its accumulation in vegetative organs and translocation to grains after anthesis, viz., increased yield by 6.2% and 7.9%, and WUE by 4.6% and 5.3%, respectively, as compared with those of the drilling sowing (DS) treatments. Pearson's correlation analysis showed that grain yield had a significantly positive correlation with soil water storage at overwintering and jointing. Moreover, grain yield was significantly positively correlated with soil water consumption in the 0–300 cm soil layer from jointing to maturity. Additionally, the seeding rate of 150 kg ha−1 with FS could obtain higher WUE and grain yield. Therefore, it is strongly recommended that the seeding rate of 150 kg ha−1 is used with FS to improve the grain yield and WUE of dryland agricultural systems in China. [ABSTRACT FROM AUTHOR]

Dense planting effectively increases maize yield while increasing stalk lodging risk. Appropriate row spacing can improve the maize population structure and stalk lodging resistance, but its physiological ecological mechanisms and interaction with planting density are unclear. Here, a two-year field experiment to determine the joint effects of row spacing and planting density on maize stem characteristics and the quantitative relationship of the light condition within a maize population with stalk lodging resistance indicated that the stalk mechanical strength showed a quadratic function relationship with photosynthetically active radiation (PAR), whereas the lodging rate showed an exponential function relationship with basal light transmittance (LT). Further, the basal LT was significantly positively correlated with basal internode thickness, dry weight per unit stem length (DWUL), mechanical and cortical tissue thickness, and lignin and cellulose contents. Increasing the planting density decreased the basal LT and PAR; correspondingly decreased the basal internode thickness, DWUL, mechanical and cortical tissue thickness, lignin and cellulose contents, and stalk mechanical strength; and increased the lodging rate, while increasing row spacing did the opposite. Thus, optimizing the row spacing enhanced the lodging resistance through LT and PAR improvement of the lower part of the population and further increased the grain yield by optimizing the yield components. The appropriate row spacing varied with the planting density. The proper strategy for high stalk lodging resistance and grain yielding under this experimental condition was 67,500 plants ha−1 density with 60 + 60 cm equal row spacing. [ABSTRACT FROM AUTHOR]

Global warming can have detrimental effects on crop production formation, but the effect of low-temperature stress on crop quality should not be ignored. Wheat is one of the main grain crops in the world, and the quality of wheat is directly related to human health. The nutritional importance of wheat in the human diet necessitates pursuing a study to collect detailed and accurate knowledge of the amino acid composition of wheat proteins under low-temperature conditions. To better understand the effect of low temperature on the composition of amino acids in mature wheat, we conducted a two-year low-temperature-controlled wheat pot experiment in artificial climate chambers with two different wheat cultivars at four low-temperature intensities during the jointing, booting, and both jointing and booting stages. Our results suggest that the contents of total amino acids, essential amino acids, and nonessential amino acids for the cold-sensitive wheat cultivar (Yangmai16) increased under the low-temperature treatments, while the contents of the cold-tolerant cultivar (Xumai30) decreased when low-temperature was applied during the jointing and double (both jointing and booting) stages. Through the amino acid score (AAS), we found that the first limiting amino acid was Lys, while the second limiting amino acid varied among Ile, Met + Cys, and Val after the low-temperature treatments. Comparing the amino acid ratio coefficients (RCs), we found that Leu and Thr in wheat grains were close to the standard protein after the low-temperature treatments, while Phe and Tyr were in a surplus, and the other essential amino acids did not meet the standard. Thus, to improve the protein quality of wheat, protective measures should be taken when low temperatures occur. [ABSTRACT FROM AUTHOR]

Core collections can act as a genetic germplasm resource for biologists and breeders. Thirty-seven phenotypic traits from 471 Miscanthus accessions in China were used to design 203 sampling schemes to screen the genetic variations in different sampling strategies. The sampling was analyzed using the unweighted pair group method with arithmetic mean (UPGMA) and the Euclidean distance (Euclid). Several parameters including the variance of phenotypic value (VPV), Shannon–Weaver diversity index (H), coefficient of variation (CV), variance of phenotypic frequency (VPF), ratio of phenotype retained (RPR), the mean difference percentage (MD%) and the variance difference percentage of traits (VD%), the range coincidence rate (CR%) and the variable rate of quantitative traits (VR%) were used to evaluate the level of representation of the primary core collections developed by the different sampling schemes. Based on the optimal sampling strategies of prior selecting accessions, a primary core collection was constructed that maintained > 99.5% of the VPV and a CR% of 100%. This study indicates that the optimal sampling scheme consisted of prior and deviation sampling methods (PD) combined with a logarithmic proportional sampling strategy (LG) of 37.4% of the actual sampling ratio. Sampling before clustering can improve several parameters including the H, CV, RPR, VPF, and CR%. Sampling strategies including the genetic diversity index (G), logarithmic proportional (LG) and the square root proportional strategy (SG) can improve the H, whilst the constant strategy (C) can improve the RPR and VPF when the sampling scale was >30%. Furthermore, the proportional strategy (P) can improve the VPV. [ABSTRACT FROM AUTHOR]

The trehalose-6-phosphate synthase (TPS) gene family plays important roles in conferring plant stress resistance, but a comprehensive analysis of the gene family is lacking for sugarcane (Saccharum spp. hybrids). The objective of this study is to document functional classification, evolutionary characterization, and expression profiling of sugarcane TPS gene (ScTPS) family. Nine putative ScTPS genes were identified and assigned to two distinct classes based on gene structure and phylogeny. Phylogenetic analysis showed that 31 TPS genes from Arabidopsis, rice and sugarcane could be divided into five distinct clades, suggesting that there were at least five orthologous groups in monocot and dicot plants. Evolution analysis of TPS genes revealed that TPS family members appeared to have undergone strong negative selection. The strength of the selective pressure differed in most clades, especially Class I TPS genes, experienced significantly stronger negative selection pressure than Class II TPS genes. There were also cis-regulatory elements related to phytohormones and abiotic stresses. Additionally, ScTPS genes were found to exhibit divergent expression in response to simulated drought, salinity, and ABA stresses. Since ScTPS genes function in sugarcane adaptation to environmental stimuli, it might be used as a molecular marker in screening sugarcane germplasm for increased stress resistance. [ABSTRACT FROM AUTHOR]

Knowledge of genetic variations can provide clues into the molecular mechanisms regulating key crop traits. Sweet potato (Ipomoea batatas (L.) Lam.) is an important starch-producing crop, but little is known about the genetic variations in starch biosynthesis and sucrose metabolism genes. Here, we used high-throughput sequencing of pooled amplicons of target genes to identify sequence variations in 20 genes encoding key enzymes involved in starch biosynthesis and sucrose metabolism in 507 sweet potato germplasms. After filtering potential variations between gene copies within the genome, we identified 622 potential allelic single nucleotide polymorphisms (SNPs) and 85 insertions/deletions (InDels), including 50 non-synonymous SNPs (nsSNPs) and 12 frameshift InDels. Three nsSNPs were confirmed to be present in eight sweet potato varieties with various starch properties using cleaved amplified polymorphic sequence (CAPS) markers. Gene copy with loss of the fifth intron was detected in IbAGPb3 genes, and loss of multiple introns were observed in IbGBSS1-1 genes and various among germplasms based on intron length polymorphism (ILP) markers. Thus, we identified sequence variations between germplasms in 20 genes involved in starch biosynthesis and sucrose metabolism, and demonstrated the diversity in intron-loss alleles among sweet potato germplasms. These findings provide critical genetic information and useful molecular markers for revealing regulatory mechanism of starch properties. [ABSTRACT FROM AUTHOR]

Sugarcane is an important crop for sugar and biofuel production worldwide. It is mostly grown on hilly area by smallholders in China, which makes harvesting by a combine harvester impractical. Harvesting sugarcane by a small-scale harvester could be more practical. However, information about the impact of small-scale mechanical harvesting on soil compaction (SC), early growth and cane yield, and its yield components is still limited. The scarcity of quantitative information is equally true for the genotype and harvesting method interaction for traits describing early growth and final yield in sugarcane. Field experiments were conducted in a plant and two consequent ratoon crops (RCs) during 2016–2018 in Kaiyuan, Yunnan Province, China, to determine the impact of small-scale mechanical harvesting followed by tractor passages (SMH) on SC, sugarcane early growth and yield, and yield components, and to determine the genotype x treatment (harvesting methods, GT) interactions. The results indicated that, when compared to manual harvesting (MH), SMH significantly (p < 0.05) increased SC at 5, 10, and 20 cm depths by 0.6, 0.71, and 0.69 MPa for the first ratoon crop (RC), respectively; and increased by 1.4, 2.02, and 1.72 MPa at 10, 20, and 30 cm depths for the second RC, respectively. The amounts of underground bud bank (UBB) in RCs were nearly nine times the buds for establishing the plant crop (PC); positive correlations between the UBB and seedling counts were observed, with the highest correlations (r = 0.8453) occurring in May for the second RC. As compared with MH, stool damage and gaps were significantly higher in SMH; meanwhile, the UBB was lower in two RCs; the amount of seedlings, plant height, and height uniformity were significantly lower in SMH. Cane yield declined more in SMH, particularly declining by 20.59% from the first RC to the second RC. With respect to sugarcane production by SMH, the existence of significant GT interactions for stool damage, gaps, early seedling, millable stalks, and height uniformity at the maturing stage suggested that genotype selection trials should be conducted under the SMH rather than in MH. [ABSTRACT FROM AUTHOR]

The changing climatic conditions are causing erratic rains and frequent episodes of moisture stress; these impose a great challenge to cotton productivity by negatively affecting plant physiological, biochemical and molecular processes. This situation requires an efficient management of water-nutrient to achieve optimal crop production. Wise use of water-nutrient in cotton production and improved water use-efficiency may help to produce more crop per drop. We hypothesized that the application of nitrogen into deep soil layers can improve water-nitrogen productivity by promoting root growth and functional attributes of cotton crop. To test this hypothesis, a two-year pot experiment under field conditions was conducted to explore the effects of two irrigation levels (i.e., pre-sowing irrigation (W80) and no pre-sowing irrigation (W0)) combined with different fertilization methods (i.e., surface application (F10) and deep application (F30)) on soil water content, soil available nitrogen, roots morpho-physiological attributes, dry mass and water-nitrogen productivity of cotton. W80 treatment increased root length by 3.1%–17.5% in the 0–40 cm soil layer compared with W0. W80 had 11.3%–52.9% higher root nitrate reductase activity in the 10–30 cm soil layer and 18.8%–67.9% in the 60–80 cm soil layer compared with W0. The W80F10 resulted in 4.3%–44.1% greater root nitrate reductase activity compared with other treatments in the 0–30 cm soil layer at 54–84 days after emergence. Water-nitrogen productivity was positively associated with dry mass, water consumption, root length and root nitrate reductase activity. Our data highlighted that pre-sowing irrigation coupled with basal surface fertilization is a promising option in terms of improved cotton root growth. Functioning in the surface soil profile led to a higher reproductive organ biomass production and water-nitrogen productivity. [ABSTRACT FROM AUTHOR]