Growth Of Strawberry Plants Research Articles

Growth, Flowering, and Fruit Production of Strawberry ‘Albion’ in Response to Photoperiod and Photosynthetic Photon Flux Density of Sole-Source Lighting

Beyond producing leafy greens, there is a growing interest in strawberry production on indoor vertical farms. Considering that sole-source lighting is one of the most important components for successful indoor crop production, we investigated how photosynthetic photon flux density (PPFD) and the photoperiod of sole-source lighting affected plant growth, flowering, and fruit production in strawberry 'Albion.' Bare-rooted strawberry plants were grown in deep water culture hydroponics inside an indoor vertical farm at 21 °C under white + blue + red light-emitting diodes at a PPFD of 200, 300, or 450 µmol∙m-2∙s-1 with a 12-h or 16-h photoperiod. Under both photoperiods, increasing PPFD from 200 to 450 µmol∙m-2∙s-1 linearly increased crown diameter by 18-64%, shoot fresh and dry mass by 38-80%, and root fresh and dry mass by 19-48%. Under a PPFD ≥ 300 µmol∙m-2∙s-1, root fresh and dry biomass increased by 95-108% and 41-44%, respectively, with an increasing photoperiod from 12 to 16 h. In addition, increasing the photoperiod from 12 to 16 h accelerated flowering by 17-21 days under a PPFD ≥ 300 µmol∙m-2∙s-1 and first fruit harvest by 17 days at a PPFD of 450 µmol∙m-2∙s-1. Regardless of PPFD, strawberry fruit production (g·m-2·month-1) increased by 372-989% under a 16-h photoperiod in comparison to under a 12-h photoperiod. In contrast, there was little effect of PPFD on fruit production. Our results suggest that increasing the PPFD or photoperiod can increase strawberry plant growth, but increasing the photoperiod can have a dominant effect on increasing early fruit production in strawberry 'Albion'.

Pengaruh Jenis dan Tingkat Ketebalan Mulsa pada Pertumbuhan dan Hasil Tanaman Stroberi (Fragaria vesca)

Strawberry development targets are limited to highlands, so crop development is directed to dry land. However, the complexity of the obstacles that must be faced is the low level of water availability for plants. Environmental engineering that leads to suppression of water loss needs to be done through the application of mulch. The purpose of this research was to study and determine the effect of the combination of types and thickness of mulch that is appropriate to increase the growth and yield of strawberry plants grown in dry land. This research was conducted in April - July 2021 at the Experimental Garden of Agrotechnopark Universitas Brawijaya in Jatikerto Village, Malang Regency. This study used a Randomized Block Design (RAK) consisting of: P1: No Mulch, P2: Straw Mulch 2 cm thick, P3: Straw Mulch 4 cm thick, P4: Straw Mulch 6 cm thick, P5: Husk Mulch 2 cm thick, P6: Husk Mulch with a thickness of 4 cm, and P7: Mulch with a thickness of 6 cm. Observational data were analyzed using ANOVA at 5% level and BNJ test at 5% level. The results showed that the combination of different types and thickness of mulch gave different effects on the growth and yield of strawberry plants. Rice straw mulch with a thickness of 4 and 6 cm produced fruit weights that were not significantly different, namely 0.48 tons/ha and 0.50 tons/ha. Ha; 92% and 100% higher than without mulch. 11.63% and 16.28% higher than rice straw with a thickness of 2 cm, 6 cm rice husk mulch produced a fruit weight of 0.45 ton/ha; 80% higher, 21.62% and 21.62% higher than without mulch, rice husk mulch with a thickness of 2 cm, and rice husk mulch with a thickness of 4 cm.   Keywords: Strawberry, Mulch, Mulch Thickness, dry land.

Effect of Global Warming on the Yields of Strawberry in Queensland: A Mini-Review

Light, temperature and rainfall affect the growth and yield of strawberry plants (Fragaria × ananassa Duch.). The objective of this review was to determine the impact of global warming on the yields of strawberry in a temperate (summer crop) and subtropical environment (winter crop) in southern Queensland, Australia. Information was collected on the changes in temperature over five decades in two locations in this area. The relationship between relative yield and temperature from published data was used to determine the impact of global warming on productivity in the two locations. Finally, the impact of elevated concentrations of CO2 and temperature on yield was examined from studies in the literature. The average daily mean temperature has increased by 2 °C over the season on the Sunshine Coast (winter crop) since 1967 (p < 0.001, R2 = 0.69). The impact of global warming has been less severe on the Granite Belt (summer crop), with a 1 °C increase in temperature (p < 0.001, R2 = 0.37). Information was collected from the literature on the yield in individual temperature regimes in an experiment and these data were compared with the maximum yield in the same experiment (relative yield). There was a negative linear relationship between relative yield and temperature in most of the published literature. The mean (± s.d. or standard deviation) estimate of the slope from the regression was −0.14 (± 0.14), the median was −0.11 and the range was from −0.51 to 0.11 (n = 14 studies). Increases in temperature were associated with a decrease in yield of 14% to 28% in the two areas in Queensland. The results of other research indicated that elevated concentrations of CO2 do not benefit productivity when combined with elevated temperatures. Further decreases in yield are expected in the next few decades in the absence of heat-tolerant cultivars or other mitigating strategies.

Transcriptome Dataset of Strawberry (Fragaria × ananassa Duch.) Leaves Using Oxford Nanopore Sequencing under LED Irradiation and Application of Methyl Jasmonate and Methyl Salicylate Hormones Treatment

This data descriptor introduces a transcriptome dataset of strawberry plant left exposed to an LED light treatment and plant hormones of Methyl Jasmonate (MeJA) and Methyl Salicylate (MeSA). These data consist of a transcriptome dataset (four libraries) obtained from the leaves of strawberry plants treated with LEDs of blue and red spectrums and the hormones of Methyl Jasmonate (MeJA) and Methyl Salicylate (MeSA), which allowed us to conduct a further analysis of the growth and development processes of strawberry plants. In addition, we describe detailed procedures on how the plants were prepared and treated and how the data were generated and processed beforehand. Further analysis of these data will significantly help to improve our understanding of the molecular mechanisms of LED light and MeJA-MeSA in strawberry plants.

Effect of emerging contaminants on soil microbial community composition, soil enzyme activity, and strawberry plant growth in polyethylene microplastic-containing soils

Emerging contaminants were found to alter the soil microbial community composition. However, no changes were observed when these compounds were added to soil containing 100 mg kg−1 HDPE microplastics.

Intensity of Supplemental Greenhouse Lighting Affects Strawberry Plant Growth, Anthracnose Infection Response, and Colletotrichum Pathogen Development in Culture

The effect of supplemental lighting on strawberry growth and anthracnose disease response of three strawberry (Fragaria ×ananassa) cultivars was evaluated in two greenhouse trials, and the effect on strawberry anthracnose pathogens (Colletotrichum sp.) was evaluated in the laboratory. The objective of the greenhouse trials was to determine the effect of various intensities of the red and blue light emitting diode (LED) light treatment on strawberry plant vigor, injury, and disease development. In these trials, the duration of supplemental light treatments was split into two 4-hour periods: dawn and dusk. The intensity of the red and blue LED bulbs was set using an adjustable dial at 1 or 3 in trial 1 and at 1, 5, or 10 in trial 2. Illuminance and photosynthetic photon flux densities of the light treatments ranged from lows of 402 lx and 5 μmol⋅m–2⋅s–1 (blue LED 1) to highs of 575 lx and 25 μmol⋅m–2⋅s–1 (red LED 1 + blue LED 3) in trial 1, and from lows of 4213 lx and 81 μmol⋅m–2⋅s–1 (red LED 1) to highs of 7051 lx (red LED 5) and 194 μmol⋅m–2⋅s–1 (red LED 10) in trial 2. Lower light intensities in trial 1 resulted in no significant differences as a result of light treatments in relative chlorophyll content, plant vigor ratings, or disease severity ratings (DSRs). However, plant injury ratings were significantly greater in plants in the wide-spectrum fluorescent (WSF) plus ultraviolet B (UVB) light treatment compared with the other treatments. Under the higher light intensities in trial 2, there were more significant effects among light treatments. Relative chlorophyll content of plants in the WSF + UVB, WSF, and red LED 1 treatments was significantly greater than that of plants in the red LED 10 treatment; however, plants in the red LED 10 treatment had the greatest injury ratings. Detached leaves from plants in the red 5 LED and red 10 LED treatments inoculated with Colletotrichum gloeosporioides received the greatest DSRs, and leaves from plants in the red LED 1 and WSF treatments received the lowest DSRs. In the laboratory, five days of exposure to supplemental lights did not prevent the growth of isolates of three species of Colletotrichum pathogens even though the intensity of the LED lights was set at their highest intensity. However, growth of isolates exposed to the WSF + UVB light treatment was slowed.

Cerium improves plant growth and fruit quality of strawberry plants under salt stress by changing the antioxidant capacity and water physiology

This study investigated the effects of cerium (Ce) on the growth and fruit quality of strawberries under salt stress. The findings revealed that salt stress markedly enhanced the activities of antioxidant enzymes and increased the contents of malonaldehyde (MDA) and hydrogen peroxide (H2O2) in leaves and the contents of anthocyanins, phenolic compounds, vitamin C (Vc), soluble sugar (SS) and titratable acid (TA) in fruits. Ce markedly improved the activities of ascorbate peroxidase, superoxide dismutase, peroxidase and catalase in leaves and the contents of anthocyanins, phenolic compounds, Vc and SS in fruits, but significantly decreased MDA and H2O2 levels in leaves and TA content in fruits under salt stress. However, salt stress significantly decreased the contents of chlorophyll (Chl) and carotenoids (Car), photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (gs), relative water content (RWC), plant height and biomass, and fruit weight and sugar-acid ratio (SAR). Compared with salt stress alone, Ce obviously increased Chl and Car contents, Pn, Tr, gs, RWC, plant height and biomass, as well as fruit weight and SAR. The above results suggested that Ce showed beneficial effects on the growth and fruit quality of strawberries under salt stress.

Transcriptomic analysis provides insight into defensive strategies in response to continuous cropping in strawberry (Fragaria × ananassa Duch.) plants

BackgroundStrawberries are an important economic fruit crop world-wide. In strawberry cultivation, continuous cropping (CC) can seriously threaten yield and quality. However, our understanding of the gene expression changes in response to CC and during subsequent defense processes is limited. In this study, we analyzed the impact of CC on the transcriptome of strawberry roots using RNA-Seq technology to elucidate the effect of CC and the subsequent molecular changes.ResultsWe found that CC significantly affects the growth of strawberry plants. The transcriptome analysis identified 136 differentially expressed genes (DEGs), including 49 up-regulated and 87 down-regulated DEGs. A Gene Ontology (GO) analysis indicated that the up-regulated DEGs were mainly assigned to defense-related GO terms, and most down-regulated DEGs were assigned to nutrient-related GO terms. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that the responsive DEGs were classified in a large number of important biological pathways, such as phenylalanine metabolism, starch and sucrose metabolism, phenylpropanoid biosynthesis, glutathione metabolism and plant-pathogen interaction. We also found that four WRKY transcription factors and three peroxidase genes involved in plant defense pathways were up-regulated in the roots of strawberry plants subjected to CC.ConclusionSeveral unigenes involved in plant defense processes, such as CNGCs, WRKY transcription factors, PR1, and peroxidase genes with highly variable expression levels between non-CC and CC treatments may be involved in the regulation of CC in strawberry. These results indicate that strawberry roots reallocate development resources to defense mechanisms in response to CC. This study will further deepen our understanding of the fundamental regulatory mechanisms of strawberry resource reallocation in response to CC.

Synergistic Effect of Plant-Growth-Promoting Rhizobacteria Improves Strawberry Growth and Flowering with Soil Salinization and Increased Atmospheric CO2 Levels and Temperature Conditions

Biofertilization with plant-growth-promoting rhizobacteria (PGPR) can positively affect the growth and health of host plants and reinforce their tolerance of stressors. Here, we investigate the use of isolated PGPR consortia from halophytes to improve strawberry growth and flowering performance under saline and elevated CO2 and temperature conditions. Growth, flower bud production, and the photosynthetic apparatus response were determined in strawberry plants grown at 0 and 85 mmol L−1 NaCl and in two atmospheric CO2-temperature combinations (400/700 ppm and 25/+4 °C, respectively). Biofertilization improved strawberry plant growth and flower bud production, independently of salinity conditions, at ambient CO2 and 25 °C, while bacterial inoculation only had a positive effect on plant growth in the presence of salt in high CO2 and at +4 °C. Biofertilizers 1 and 3 generated the largest biomass of strawberries at 400 ppm CO2 and 0 and 85 mmol L−1 NaCl, respectively, while biofertilizer 1 did so in the presence of salt and in an atmosphere enriched with CO2 and at +4 °C. The effect of the consortia was mediated by bacterial strain PGP properties, rather than by an improvement in the photosynthetic rate of the plants. Furthermore, biofertilizers 1 and 2 increased the number of flower buds in the absence of salt, while biofertilizers 3 and 4 did so for salt-inoculated plants at 400 ppm CO2 and at 25 °C. There was no effect of inoculation on flower bud production of plants grown at high CO2 and at +4 °C. Finally, we concluded that the effect of bacterial inoculation on strawberry growth and flowering depended on the type of bacterial strain and growth conditions. This highlights the importance of developing studies considering stress interaction to assess the real potential of biofertilizers.

Effect of Light-emitting Diodes, Ultraviolet-B, and Fluorescent Supplemental Greenhouse Lights on Strawberry Plant Growth and Response to Infection by the Anthracnose Pathogen Colletotrichum gloeosporioides

Supplemental lighting is frequently used to extend daylength for strawberries (Fragaria ×ananassa) grown in greenhouses and high tunnels; however, information is limited on the effect of these lights on disease development. We evaluated the effect of ambient light and six supplemental light treatments [red, blue, and white light-emitting diodes (LEDs), separately; a combination of red, blue, and white LEDs; wide-spectrum fluorescent (WSF); and WFS + ultraviolet B (UV-B)] on plant growth and disease response of strawberries grown in a greenhouse. Plants were exposed to supplemental light treatments for 17 h each day. In the WSF+UV-B treatment, plants were exposed to WSF light during the day and to UV-B light for 3 hours during the night. Two trials were conducted; each trial contained five or six cultivars and was replicated three times. Twice during each trial, detached leaves from each cultivar in each light treatment were inoculated with a conidial suspension of the anthracnose crown rot pathogen, Colletotrichum gloeosporioides and rated for disease severity 10 days later. There was a significant difference due to light treatment and to cultivar in relative chlorophyll content and plant growth parameters. Plant injury ratings were lowest in the white LED, WSF, and WSF+UV-B treatments. Plants in the combination LED and red LED light treatments received higher injury, lower vigor scores, and lower relative chlorophyll content values than plants in all other light treatments. After inoculation of detached strawberry leaves with C. gloeosporioides in Trial 1, there was a significant effect due to light treatments on disease severity ratings (DSRs) after 18 weeks’ exposure to light treatments with the DSRs in the WSF+UV-B treatment being lower than those in all other treatments except those in the red LED treatment. There was not a significant effect in DSRs due to light treatments after 24 weeks in Trial 1 or after 4 or 22 weeks in Trial 2. There were significant effects due to cultivar on DSRs in both trials: ‘Strawberry Festival’, ‘Pelican’, and ‘Seascape’ received the lowest DSRs. This study showed an effect of supplemental light on several strawberry plant growth parameters, including a harmful effect of high-intensity red LED irradiation.

Endophytic Trichoderma spp. can protect strawberry and privet plants from infection by the fungus Armillaria mellea.

Armillaria mellea is an important fungal pathogen worldwide, affecting a large number of hosts in the horticulture and forestry industries. Controlling A. mellea infection is expensive, labour intensive and time-consuming, so a new, environmentally friendly management solution is required. To this effect, endophytic Trichoderma species were studied as a potential protective agent for Armillaria root rot (ARR) in strawberry and privet plants. A collection of forty endophytic Trichoderma isolates were inoculated into strawberry (Fragaria × ananassa) plants and plant growth was monitored for two months, during which time Trichoderma treatment had no apparent effect. Trichoderma-colonised strawberry plants were then inoculated with A. mellea and after three months plants were assessed for A. mellea infection. There was considerable variation in ARR disease levels between plants inoculated with different Trichoderma spp. isolates, but seven isolates reduced ARR below the level of positive controls. These isolates were further tested for protective potential in Trichoderma-colonized privet (Ligustrum vulgare) plants where five Trichoderma spp. isolates, including two highly effective Trichoderma atrobrunneum isolates, were able to significantly reduce levels of disease. This study highlights the potential of plants pre-colonised with T. atrobrunneum for effective protection against A. mellea in two hosts from different plant families.

Unravelling the Effect of Triacontanol in Combating Drought Stress by Improving Growth, Productivity, and Physiological Performance in Strawberry Plants.

To explore the effects of triacontanol (TR) on drought tolerance of strawberry plants (cv Fertona), two field experiments were carried out to study the effects of three supplementary foliar TR rates (0, 0.5, and 1 ppm) under the following three levels of water irrigation: 11 m3/hectare (40% of water holding capacity (WHC) severe as a drought treatment, 22 m3/hectare (80% of WHC) as moderate drought stress, and normal irrigation with 27 m3/hectare (100% of WHC) server as a control treatment. TR treatments were applied five times after 30 days from transplanting and with 15-day intervals. The results showed that drought stress (40% and 80%) markedly decreased the growth, fruit yield, and chlorophyll reading, as well as the gas exchange parameters (net photosynthetic rate, stomatal conductance, and transpiration rate). Meanwhile, drought stress at a high rate obviously increased antioxidant enzyme activities such as superoxide dismutase (SOD), peroxidase (POX), and catalase (CAT) contents in the leaves of the strawberry plants. The moderate and high drought stress rates enhanced some strawberry fruit quality parameters such as total soluble solids (TSS), vitamin C, and anthocyanin content compared to the control. Additionally, TR increased the activities of SOD, POX, and CAT. TR treatment significantly increased the chlorophyll contents, gas exchange parameters (photosynthetic rate and stomatal conductance), and water use efficiency (WUE). Plant height, fruit weight, and total biomass were increased also via TR application. Total yield per plant was increased 12.7% using 1 ppm of TR compared with the control. In conclusion, our results suggested that TR application could relieve the adverse effects of drought stress on the growth of strawberry plants by enhancing the antioxidant enzymes, photosynthesis rate, and WUE of the leaves.

Application of automated image colour analyses for the early-prediction of strawberry development and quality.

Labour and production costs are considered major production challenges for strawberry (Fragaria sp.) farmers, due to the reliance on manual harvesting methods. Automation has been proposed as a desirable solution, in particular robotic-driven harvesting with in-built decision making for determination of fruit ripeness and early-prediction of harvest timing and conformity to industry quality parameters (fruit weight and length). To support the development of these automated processes, the work presented herein explored the capacity to utilise automated image analysis for the prediction of strawberry quality measures. This involved the hydroponic growth of strawberry plants under controlled conditions and the daily collection of photographs of individual flowers and fruit. Machine learning (ML)-driven image colour extraction from the collected 1685 strawberry images utilised object detection to identify flowers and fruit within images, followed by cropping and counting of remaining image pixels, which were assigned based on pixel RGB to one of 10 pre-defined groups: achromatic, blue, cyan, green, orange, pink, purple, red, white, and yellow. These colour measures were utilised as inputs for general regression with 10-fold cross-validation to generate 3 models: for the prediction of current-state fruit developmental stage (R2 = 0.9071), current-state fruit length (R2 = 0.8565), and days remaining until harvest (R2 = 0.8694). Additionally, current-state fruit development stage and current-state length were utilised as inputs for general regression with 10-fold cross-validation to develop predictive models for the endpoint (harvest) key quality measures: fruit harvest-length (R2 = 0.8817) and fruit harvest-weight (R2 = 0.7252). Noting that days to harvest could be accurately predicted up to 15 days prior to harvest, and the harvest quality measures could be accurately predicted up to 22 days prior to harvest, the models presented herein may be utilised to increase automation and thereby improve efficiency in the scheduling of harvesting and quality control of strawberry farming.

MDAM-DRNet: Dual Channel Residual Network With Multi-Directional Attention Mechanism in Strawberry Leaf Diseases Detection.

The growth of strawberry plants is affected by a variety of strawberry leaf diseases. Yet, due to the complexity of these diseases' spots in terms of color and texture, their manual identification requires much time and energy. Developing a more efficient identification method could be imperative for improving the yield and quality of strawberry crops. To that end, here we proposed a detection framework for strawberry leaf diseases based on a dual-channel residual network with a multi-directional attention mechanism (MDAM-DRNet). (1) In order to fully extract the color features from images of diseased strawberry leaves, this paper constructed a color feature path at the front end of the network. The color feature information in the image was then extracted mainly through a color correlogram. (2) Likewise, to fully extract the texture features from images, a texture feature path at the front end of the network was built; it mainly extracts texture feature information by using an area compensation rotation invariant local binary pattern (ACRI-LBP). (3) To enhance the model's ability to extract detailed features, for the main frame, this paper proposed a multidirectional attention mechanism (MDAM). This MDAM can allocate weights in the horizontal, vertical, and diagonal directions, thereby reducing the loss of feature information. Finally, in order to solve the problems of gradient disappearance in the network, the ELU activation function was used in the main frame. Experiments were then carried out using a database we compiled. According to the results, the highest recognition accuracy by the network used in this paper for six types of strawberry leaf diseases and normal leaves is 95.79%, with an F1 score of 95.77%. This proves the introduced method is effective at detecting strawberry leaf diseases.

Bio-organic Fertilizer with Bacillus subtilis F2 Promotes Strawberry Plant Growth and Changes Rhizosphere Microbial Community

Bio-organic Fertilizer with Bacillus subtilis F2 Promotes Strawberry Plant Growth and Changes Rhizosphere Microbial Community

Evaluation of Single-Cropping under Reduced Water Supply in Strawberry Cultivation

Genotype, environment, and cultivation system strongly influence strawberry yield and quality. Specifically, the growth of strawberry plants is dependent on the water supply. Nevertheless, the abuse of water in agriculture is necessitating the choice of the lowest water-consumptive plants. The following study showed the performance of ‘Romina’, ‘Sibilla’, and ‘Cristina’ cultivars, grown in open-field conditions, and treated with three doses of water (W): 100% local standard regime, and 20% (W80) and 40% (W60) reductions. The average amount of water administered for W100, W80, and W60 was 1120 m3 ha−1, 891 m3 ha−1, and 666 m3 ha−1, respectively. The water treatment at W60 negatively affected the plant growth and yield, resulting in reduced plant height, leaf number, leaf length and width, and a minor yield. Instead, fruit quality showed higher values of total soluble solids and titratable acidity. Conversely, plants watered with W80 showed results similar to the control (W100) in terms of development and yield. In conclusion, it is possible to assume that a reduction of water is desirable, guaranteeing economic and environmental gains for farmers.

Applying Different Magnetic Water Densities as Irrigation for Aeroponically and Hydroponically Grown Strawberries

Due to the scarcity of water, it is necessary to develop an environmentally friendly method for increasing water productivity and crop production. An experiment was conducted to assess the effects of different magnetic levels (magnetic water level 1 (MWL 1) = 3800 Gauss, magnetic water level 2 (MWL 2) = 5250 Gauss, and magnetic water level 3 (MWL 3) = 6300 Gauss, as well as normal water (NW) as a control) in combination with three soilless culture systems (a nutrient film technique (NFT) hydroponics system, a tower aeroponics system, and a pyramidal aeroponics system. The results showed that the utilization of magnetic water had significant effects on the yield and growth of strawberry plants The tower aeroponic system under MWL 3 produced the highest yield and water productivity, with increases of 80.9% and 89%, respectively, over the control. The tower aeroponic system under MWL 3 produced the highest yield and water productivity, with increases of 80.9% and 89%, respectively, over the control. In addition, as compared to the NW, the NFT system increased yield and water productivity by 71.1% and 79.3%, respectively, whilst the pyramidal system increased yield and water productivity by 66.87% and 82%, respectively. Furthermore, when compared to the control, the combination of the NFT system and magnetic water level 3 (MWL 3) resulted in the most leaves, largest stem diameter, and largest leaf area of the strawberry plants resulted in the most leaves, stem diameter, and leaf area of strawberry plants. In comparison to all other treatments, this combination produced the best fruit quality and yield, as well as its constituents, such as titratable acidity, total soluble solids, and fruit hardness. This study found that combining magnetic therapy with soilless culture techniques resulted in increased yield and water productivity. In addition, water and fertigation solution usage in the NFT, tower, and pyramidal systems dropped by 4.8%, 6%, and 4.8%, respectively. Furthermore, it enhanced plant morphology and plant quality.

Supplemental light application can improve the growth and development of strawberry plants under salinity and alkalinity stress conditions

The use of complementary light spectra is a potential new approach to studying the increase in plant resilience under stress conditions. The purpose of this experiment was to investigate the effect of different spectra of complementary light on the growth and development of strawberry plants under salinity and alkalinity stress conditions. Plants were grown in the greenhouse under ambient light and irradiated with blue (460 nm), red (660 nm), blue/red (1:3), and white/yellow (400–700 nm) light during the developmental stages. The stress treatments were as follows: control (non-stress), alkalinity (40 mM NaHCO3), and salinity (80 mM NaCl). Our results showed that salinity and alkalinity stress decreased fresh and dry weights and the number of green leaves, and increased chlorotic, tip burn, and dry leaves. The blue and red spectra had a greater effect on reducing the effects of stress compared to other spectra. Stress conditions decreased SPAD and RWC, although blue light increased SPAD, and blue/red light increased RWC under stress conditions. Blue/red and white/yellow light had the greatest effect on reproductive traits. Stress conditions affected fruit color indicators, and red and blue light had the most significant effect on these traits. Under stress conditions, sodium uptake increased, while K, Ca, Mg, and Fe uptake decreased, markedly. Blue and red light and their combination alleviated this reducing effect of stress. It can be concluded that the effects of salinity and alkalinity stresses can be reduced by manipulating the supplemental light spectrum. The use of artificial light can be extended to stresses.

Effect of Some Soilless Culture Systems on Growth and Productivity of Strawberry Plants

Effect of Some Soilless Culture Systems on Growth and Productivity of Strawberry Plants

Use of Piriformospora indica to Promote Growth of Strawberry Daughter Plants

As an endophytic fungus, the growth-promoting effects of Piriformospora indica have been widely confirmed in many of its host plants. In this study, we investigated the influences of P. indica colonization on the growth of the daughter plants of two strawberry cultivars, ‘Benihoppe’ and ‘Sweet Charlie.’ The results showed that the fungus colonization significantly promoted the growth of the daughter plants of both of the two strawberry varieties. Its colonization greatly improved almost all of the growth parameters of the ‘Benihoppe’ daughter plants, including the above-ground fresh weight, above-ground dry weight, root fresh weight, root dry weight, plant height, petiole length, leaf area, number of roots and chlorophyll content. However, the fungus colonization showed significant improving effects on only the above-ground fresh weight, root fresh weight and root dry weight of ‘Sweet Charlie.’ Surprisingly, the average root length of ‘Benihoppe’ and ‘Sweet Charlie’ was suppressed by about 14.3% and 24.6%, respectively, by P. indica. Moreover, after P. indica colonization, the leaf nitrate reductase activity and root activity upregulated by 30.12% and 12.74%, and 21.85% and 21.16%, respectively, for the ‘Benihoppe’ and ‘Sweet Charlie’ daughter plants. Our study indicated that P. indica could promote the growth of strawberry daughter plants by improving rooting, strengthening photosynthetic pigments production and nutrient absorption and accelerating biomass accumulation. The fungus shows great potential to be used in the strawberry industry, especially in the breeding of daughter plants.