查看更多>>摘要：? 2021Traditional fertilization and the loss of Nitrogen (N) is a common phenomenon in agriculture. Application of urea with urease inhibitor is an alteration measure of urea hydrolysis and N metabolism. Hence, the objective of this study was to determine the short-term foliar application effect of N-(n?butyl) thiophosphoric triamide (NBPT) on N metabolism, physiological and biochemical changes in the pineapple plant. At 4 month after planting (MAP), 1% urea (Urea) and 1% urea with NBPT (NLU) were applied. Data on urease enzyme activity, internal urea content, inorganic N [ammonium (NH4+) and nitrate (NO3?)], amino acids, total soluble protein, NBPT content, lipid peroxidase (MDA) activity, and electrolyte leakage were recorded for 10 days after treatment (DAT). The results indicated that the NBPT was taken up by the plant, thereby a clear inhibition of the urease activity was observed in pineapple leaf. A higher amount of urea content and a lower amount of NH4+ content in the leaf were the evidence of hydrolysis inhibition by NBPT. Consequently, the contents of amino acid and protein were diminished upon NBPT treatment which demonstrated a change in N metabolism. In addition, amino acid composition demonstrated that amide forms of amino acids were the major components of the decreased amino acid pool. In conclusion, lower MDA activity and electrolyte leakage were also observed under NBPT treated plants indicate that NBPT could release abiotic stress to some extent by protecting the cell wall from damage.
查看更多>>摘要：? 2021 Elsevier B.V.With increasing urbanisation and consumer concerns over food miles, indoor urban plant factories are gaining popularity. These offer precise regulation of the crop environment, but optimal light requirements vary between species and according to grower specifications. Here we introduce a novel assessment framework to optimise light quality in urban plant factories accounting for yield, resource use efficiency and flavour, factors that have only been studied separately in previous research. Yield, water and energy use efficiency and flavour of sweet basil (Ocimum basilicum cv. Genovese) and tomato (Solanum lycopersicum cv. Micro-Tom) were determined for plants grown supplied with 100% blue, 66% blue + 33% red, 33% blue + 66% red, or 100% red lighting. In both species, 66% red and 100% red optimised water use efficiency and energy use respectively. For basil, 100% blue light maximised leaf biomass, while 66% red enhanced leaf flavouring volatiles. In Micro-Tom, all treatments produced similar fruit biomass, but 100% red light enhanced flavour-related volatiles in foliage. By considering trade-offs between yield, efficiency and flavour, growers can select bespoke lighting treatments to optimise their product according to specific market demands and minimise environmental impacts.
查看更多>>摘要：? 2021 Elsevier B.V.Valine-glutamine (VQ) motif-containing proteins are plant-specific transcription factors with critical functions in plant growth, development and defense reactions. However, no systematic study has been performed for VQ family genes in cucumber to date. In this work, a total of 32 VQ family genes (CsVQ1–CsVQ32) were identified in cucumber, which were unevenly distributed on seven cucumber chromosomes (chromosomes 1–7). The CsVQs were divided into nine distinct groups (group I–IX) according to their phylogenetic relationships, with the members of the same group sharing highly conserved motif compositions. Gene structure analysis suggested that the CsVQ genes were generally lack of introns. Gene duplication analysis revealed that two and 11 CsVQ genes were located in the tandem and segmental duplication regions of cucumber chromosomes, respectively. Tissue expression profiles obtained from RNA-seq data showed that most CsVQ genes were differentially expressed in different tissues and developmental stages. Quantitative real-time PCR (qRT-PCR) of six selected CsVQ genes (CsVQ6, CsVQ9, CsVQ12, CsVQ13, CsVQ16 and CsVQ20) showed that all of them were regulated by cold, drought and salt stresses. In addition, RNA-seq analysis revealed changes in the expression of some CsVQ genes (such as CsVQ2, CsVQ9, CsVQ12, CsVQ13, CsVQ20 and CsVQ22) under downy mildew (DM) and powdery mildew (PM) treatments. Our findings provide a theoretical basis for studying the potential roles of CsVQ genes in the development and stress response of cucumber in the future.
查看更多>>摘要：? 2021 Elsevier B.V.Plant heat stress transcription factors (Hsfs) belong to a very large gene family and play dominant roles in response to heat stress. Here, we report the functional analysis of VaHsfC1, a class C Hsf gene from Vitis amurensis, and involved in multiple abiotic stresses. The structure of VaHsfC1 contains a typical HSF domain for DNA-binding at N terminus. Phylogenetic analysis revealed that VaHsfC1 belongs to the C1 family of Hsfs. VaHsfC1 was highly induced by heat, cold, exogenous abscisic acid (ABA) and salinity, respectively. Unusually, VaHsfC1was preferentially localized in nucleus, but less in the cytosol. Also, no transcriptional activation was detected for the protein in yeast cells. Ectopic VaHsfC1 expression in Arabidopsis enhanced heat tolerance characterized by the increased survival rate, higher chlorophyll content, reduced electrolyte leakage, and activated expressions of ascorbate peroxidase (Apx2) and heat shock protein (HSP) expression compared to the WT. Interestingly, overexpression of VaHsfC1 in Arabidopsis could also increase the cold tolerance, as reveled from a series changes at the physiological and biochemical steps, as well as at the transcript levels of CORs in the CBF-dependent responsive pathway. Additionally, the growth of VaHsfC1-overexpressing Arabidopsis showed enhanced seed ABA hypersensitivity during germination and cotyledon development, and a significant reduction in stomatal aperture was also observed in overexpression lines. Furthermore, VaHsfC1-overexpressing lines displayed salt-hypersensitive phenotype with a lower rates both in germination and cotyledon greening, and the inhibition of root growth. Our findings demonstrated that the complex nature of VaHsfC1 in mediating multiple abiotic stress responses, as a key component to further understanding of the ‘crosstalk’ mechanism of multiple abiotic stress response in plants.
查看更多>>摘要：? 2021 Elsevier LtdNatural agricultural inputs in sweet pepper cultivation can be beneficial for nutritional quality, and environmental and food safety. This research assessed the effect of the combined use of clove basil (Ocimum gratissimum) aqueous extract and cassava peel compost on the nutrients, pesticide residues, yield and antioxidant properties of sweet pepper fruits. The experiment was a split plot design of 04 blocks with 03 plots each and 03 repetitions, conducted in pots and in the field. The soil was amended with compost at 1kg/4kg and 2kg/3kg in pots, with 3kg/plot and 6kg/plot on field experiment, and 26.3 g of NPK (20.10.10) per plant was used as an inorganic amendment both in pots and field. Plants in both experiments were sprayed with clove basil extract, insecticide lambda-cyhalothrin or water. Sweet pepper fruits cultivated with composts and sprayed with clove basil extract exhibited the highest values of nutritional parameters, antioxidant properties and increased the yield by 93% in pots and 187% on field, as compared with synthetic fertilizer treatments. Organic fruits were free from pesticide residues and had the best values of Na/K and Ca/P ratios which are good indicators of their nutritional values. Sweet pepper plants sprayed with lambda-cyhalothrin or from farmers contained lambda-cyhalothrin at concentration of 0.0199 mg/kg. These results show that organic treatments improved the fruit nutrients, health-promoting properties and safety, and could be used to enhance the nutritional quality of sweet pepper while providing an efficient way of sustainable agriculture.
查看更多>>摘要：? 2022Root development is essential for the growth and vegetative propagation in grapevine. The proper concentration of auxin can promote root development and induce secondary roots or adventitious roots formation. MicroRNAs are involved in regulating the development of roots and played a significant role in grape adventitious roots formation. Hence, in order to verify the molecular mechanism of Indoleacetic Acid (IAA) induced grape root development, the two key time points 10, 30 d and four different IAA concentrations 0, 0.2, 1 and 5 mg/L of root development of grape tissue culture cuttings were analyzed by small RNA transcriptome. A total of 187 known miRNAs and 117 novel miRNAs which showed different expression patterns were identified. The expression levels of the differentially expressed miRNAs and target genes were confirmed by RT-qPCR, and the results showed that the expression of miRNAs and their target genes which associated with auxin signal-related (vvi-miR167, miR164 and miR160), stress response-related (vvi-miR395, miR398 miR169 and novel-miR103), cell fate transformation-, enlargement- and proliferation-related (vvi-miR399, miR166, miR319, miR3633 and miR396) were inconsistent with the RNA-seq results. Furthermore, most of the predicted target genes were negatively regulated by corresponding miRNAs. The function of vvi-miR164b was identified by gene transformation in Arabidopsis thaliana, and the number of lateral roots in transgenic lines increased significantly, suggesting that differentially expressed vvi-miR164b plays an active role in grape lateral root development. Comparison of miRNA expression patterns between the IAA treatment group and control group (CK) may provide a means to reveal the molecular mechanism of miRNA-mediated regulation of grape root development under auxin treatment. In summary, these results gave us useful information to better understanding the root development in fruit tree.
查看更多>>摘要：? 2022The subsequent plant growth is determined by tomato seedling quality which is affected by light intensity. The present study proposes a method for obtaining the regulatory target value by using the U-chord length curvature method based on the dry weight model-fitted curve characteristics to obtain the optimum light intensity at the seedling stage. Tomato seedlings were selected as the experimental material, and six photosynthetic photon flux densities (PPFDs) were set under completely artificial side lighting. Depending on the scattering trend, the tomato shoot dry weights (SDWs) were fitted by the polynomial, logarithmic, and half logistic function models after optimization of parameters by using the differential evolution algorithm (DE-HLFM). According to the curve variation characteristics, the discrete curvature values corresponding to the models calculated using the U-chord length curvature method were 335, 108, and 241.3 μmol·m?2·s?1, respectively. Physiological tomato growth indicators exhibited that L4 had the smallest root–shoot ratio and the highest level of seedling index and SDW significance. Moreover, L4 had the highest SDW per PPFD improvement efficiency. Thus, tomato seedlings under L4 exhibited the best quality and highest efficiency among those under the six PPFDs. DE-HLFM optimization was closest to the optimal PPFD L4 (243.17 ± 4.37 μmol·m?2·s?1), indicating that DE-HLFM is the most suitable model with a coefficient of determination (R2) of 0.99897 and root-mean-square error of 0.00554. Thus, the PPFD corresponding to the maximum curvature point of the appropriate model exhibited physiological and production regulation significance. In conclusion, based on the curve characteristics, the curve feature point obtained using the U-chord curvature method can be used as the control target value for the precise control of the artificial controllable light environment.
查看更多>>摘要：? 2021Due to the economic importance of strawberry, many countries have established national breeding programs aimed at improving the flowering time and fruiting season to achieve year-round fruit availability. The ability of crops to produce fruits throughout the year with “flowering on command” is still a challenge in strawberry production systems. Although growth promotion by dark septate endophytic (DSE) fungi has been reported, the symbiotic association that alters flowering behaviors in photoperiodic fruit crops has not been studied. Here we established an experimental scheme for inducing the short-day (SD) strawberry cultivar Fragaria vesca to initiate flowering under a long-day (LD) photoperiod in symbiotic association with DSE fungus. We evaluated the relationship between growth-promoting and flower-inducing activities using Pearson's correlation analysis. Symbiotic association with C. chaetospira SK51 markedly stimulated SD strawberry cultivar to initiate early flowering, with the greatest flower induction (94.8%) and highest number of fruits (10.6 fruits/plant) during cultivation under a 16-h LD photoperiod at 23 °C, defined as non-flower-inductive conditions, considered as a new finding. We found that the interactions between C. chaetospira SK51 and strawberry plants markedly contributed to accelerating the earliness of the flowering time, as flower buds were initiated 90 days earlier than in the untreated control. Interestingly, we show that plant response in flowering by co-cultivation of C. chaetospira SK51 is constantly induce under various soil types and pHs. Based on Pearson's correlation coefficient analysis, we suggest that flowering behavior has a weakly non-significant relationship with growth-promoting activities, indicating that the control of flowering has a different or indirect pathway. Strawberry plants in symbiosis with C. chaetospira SK51 might be well-adapted to all regions and help preserve crops resilience against adverse climate conditions. These findings provide an essential resource and new insight for photoperiodic flowering research and innovation that can be adopted to deliver sustainable solutions that eventually will lead to extending and increasing crop production.
查看更多>>摘要：? 2021 Elsevier B.V.A high-speed camera was used to study the motions of litchi fruit during vibrational harvesting to investigate fruit detachment patterns. The quasi-static traction and tilting tests, as well as vibrational detachment tests using frequencies of 9, 12 and 15 Hz and amplitudes of 100 and 130 mm, were conducted on ‘Huaizhi’ litchi. A MATLAB program was developed to estimate the motion parameters of the fruit during shaking. The quasi-static tests indicated that the detachment force decreased as the tilting angle increased from 0° to 60° and that most fruit would detach at a certain tilting angle (average value of 62.6°) without traction. The vibrational detachment tests suggested two main reasons for fruit detachment: the stress exceeded the ultimate stress at the fruit–stem junction and fatigue induced by the alternating stress at the junction. Inducing a large tilting angle during shaking was advantageous for creating a high degree of stress at the fruit–stem junction and for achieving a high detachment speed. In general, appropriate increases in the vibration amplitude and frequency decreased the degree of fruit damage by causing fewer impacts. In this study, 12 Hz/130 mm and 15 Hz/100 mm were the optimal parameter combinations to achieve limited litchi fruit damage and high detachment speeds.
查看更多>>摘要：? 2022Insufficient pollination reduces the fruit and seed setting rate and limits the chance of outcrossing in crop plants that are highly dependent on insect pollination, thus affecting the quality and growth rate of progenies. To investigate the effect of pollination methods on the fruit growth rate, fruit yield, oil yield and seed oil quality, four pollination methods, such as (1) in cages with honeybees (Apis mellifera L.), the control in cages with (2) hand pollination, (3) wind pollination, and (4) self-pollination were used to pollinate the flowers of oil tree peony (Paeonia ostii T. Hong et J.X. Zhang). Results showed that the mean growth rate and cumulative growth rate of fruit diameter, follicle length and diameter pollinated by honeybees were significantly higher than that of the control group (hand, wind and self-pollination). Fruit development ratio, seed setting rate and the number of seeds per fruit pollinated by honeybees were significantly higher than self-pollination. Moreover, pollination by honeybees increased yield per fruit by 56.28%, 59.42% and 126.27% compared to the hand, wind and self-pollination, respectively. Compared with hand pollination, the oil yield of honeybee-pollinated tree peony increased by 12.24%. However, the total unsaturated fatty acidcontent of seed oil was not significantly changed with different pollination methods. Our study demonstrated that bee pollination is essential to reach rapid fruit development and high seed yield in oil tree peony.
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