Mature Plants Research Articles

Coordinate Normalization of Live-Cell Imaging Data Reveals Growth Dynamics of the Arabidopsis Zygote.

Polarization of the zygote defines the body axis during plant development. In Arabidopsis (Arabidopsis thaliana), the zygote becomes polarized and elongates in the longitudinal direction, ultimately forming the apical-basal axis of the mature plant. Despite its importance, the mechanism for this elongation remains poorly understood. Based on live-cell imaging of the zygote, we developed new image analysis methods, referred to as coordinate normalization, that appropriately fix and align positions in an image, preventing fluctuation across a temporal sequence of images. Using these methods, we discovered that the zygote elongates only at its apical tip region, similar to tip-growing cells such as pollen tubes and root hairs. We also investigated the spatiotemporal dynamics of the apical tip contour of the zygote and observed that the zygote tip retains its isotropic, hemispherical apical shape during cell elongation. By looking at the elliptical fitting of the contour over time, we further discovered that the apical cell tip becomes thinner at first and then thickens, with a transient increase in growth speed that is followed by the first cell division. We performed the same series of analyses using root hairs and established that both the hemispherical tip shape and the changes in growth rate associated with changes in tip size are specific to the zygote. In summary, the Arabidopsis zygote undergoes directional elongation as a tip-growing cell, but its tip retains an unusual isotropic shape, and the manner of growth changes with the developmental stage.

Evaluation of Growth Conditions, Antioxidant Potential, and Sensory Attributes of Six Diverse Microgreens Species

Microgreens belong to a class of functional foods with valuable nutritional elements and diverse health benefits when consumed as food supplements. Its consumption has increased sharply due to the abundance of different health-promoting components than their mature plants. The present study investigated the growth conditions and nutritional profiles of six crops (mungbean, lentil, red radish, pearl-millet, mustard, and red cabbage) as microgreens grown under the light with a 16 h light/8 h dark cycle. Firstly, the optimum temperature and the day of harvesting of each of the microgreens for their maximum yield were standardized. The optimum temperature ranged from 24 to 28 °C, and the best stage for their harvesting ranged from the 6th to 13th day for all six microgreens species. Physiological parameters such as height, yield, color, moisture content, seed weight to fresh weight (FW) ratio, and FW to dry weight (DW) were also estimated. All the microgreens were analyzed for the total phenolics content, total anthocyanin content, vitamin C, free radical scavenging activity, dietary fiber, and phytic acid contents at the harvesting stage. Total phenolics, total anthocyanin, and vitamin C contents ranged from 55 to 1240 mg/100 g, 25 to 186 mg/100 g, and 22 to 86 mg/100 g, respectively, in the studied microgreens. Red cabbage and pearl-millet microgreens accumulated higher phenolics than other studied microgreens, while total anthocyanin content was higher in red radish and pearl-millet microgreens. Vitamin C content was recorded as highest in red cabbage microgreens. DPPH-based free radical scavenging activity ranged from 62–84% and was highest in red cabbage microgreens. All the microgreens were also analyzed for their dietary fiber (DF) content which ranged from 2.5–12.5% and was recorded as maximum in pearl millet microgreens. The findings of this study offer helpful information on the growth circumstances necessary to produce microgreens with the greatest nutrient and health benefits.

Blue Photons from Broad-Spectrum LEDs Control Growth, Morphology, and Coloration of Indoor Hydroponic Red-Leaf Lettuce

For indoor crop production, blue + red light-emitting diodes (LEDs) have high photosynthetic efficacy but create pink or purple hues unsuitable for workers to inspect crops. Adding green light to blue + red light forms a broad spectrum (white light), which is created by: phosphor-converted blue LEDs that cast photons with longer wavelengths, or a combination of blue, green, and red LEDs. A broad spectrum typically has a lower energy efficiency than dichromatic blue + red light but increases color rendering and creates a visually pleasing work environment. Lettuce growth depends on the interactions of blue and green light, but it is not clear how phosphor-converted broad spectra, with or without supplemental blue and red light, influence crop growth and quality. We grew red-leaf lettuce 'Rouxai' in an indoor deep-flow hydroponic system at 22 °C air temperature and ambient CO2. Upon germination, plants received six LED treatments delivering different blue fractions (from 7% to 35%) but the same total photon flux density (400 to 799 nm) of 180 μmol·m-2·s-1 under a 20 h photoperiod. The six LED treatments were: (1) warm white (WW180); (2) mint white (MW180); (3) MW100 + blue10 + red70; (4) blue20 + green60 + red100; (5) MW100 + blue50 + red30; and (6) blue60 + green60 + red60. Subscripts denote photon flux densities in μmol·m-2·s-1. Treatments 3 and 4 had similar blue, green, and red photon flux densities, as did treatments 5 and 6. At the harvest of mature plants, lettuce biomass, morphology, and color were similar under WW180 and MW180, which had different green and red fractions but similar blue fractions. As the blue fraction in broad spectra increased, shoot fresh mass, shoot dry mass, leaf number, leaf size, and plant diameter generally decreased and red leaf coloration intensified. Compared to blue + green + red LEDs, white LEDs supplemented with blue + red LEDs had similar effects on lettuce when they delivered similar blue, green, and red photon flux densities. We conclude that the blue photon flux density in broad spectra predominantly controls lettuce biomass, morphology, and coloration.

Infrared thermography of in situ natural freezing and mechanism of winter-thermonasty in Rhododendron maximum.

Evergreen leaves of Rhododendron species inhabiting temperate/montane climates are typically exposed to both high radiation and freezing temperatures during winter when photosynthetic biochemistry is severely inhibited. Cold-induced "thermonasty," that is, lamina rolling and petiole curling, can reduce the amount of leaf area exposed to solar radiation and has been associated with photoprotection in overwintering rhododendrons. The present study was conducted on natural, mature plantings of a cold-hardy and large-leaved thermonastic North American species (Rhododendron maximum) during winter freezes. Infrared thermography was used to determine initial sites of ice formation, patterns of ice propagation, and dynamics of the freezing process in leaves to understand the temporal and mechanistic relationship between freezing and thermonasty. Results indicated that ice formation in whole plants is initiated in the stem, predominantly in the upper portions, and propagates in both directions from the original site. Ice formation in leaves initially occurred in the vascular tissue of the midrib and then propagated into other portions of the vascular system/venation. Ice was never observed to initiate or propagate into palisade, spongy mesophyll, or epidermal tissues. These observations, together with the leaf- and petiole-histology, and a simulation of the rolling effect of dehydrated leaves using a cellulose-based, paper-bilayer system, suggest that thermonasty occurs due to anisotropic contraction of cell wall cellulose fibers of adaxial versus abaxial surface as the cells lose water to ice present in vascular tissues.

Morphology and anatomy of rhizome and root structures in seven Pteris L. species (Pteridaceae) from Southwestern Nigeria

Morphological and anatomical structures of seven Pteris species from various locations in Southwestern Nigeria were examined. This study aimed to affirm the affinities and relevance of rhizome and root structures within the genus Pteris. Mature healthy plants of each species were collected, and morphological observations of rhizomes and roots were documented for each species. The transverse sections of rhizomes were prepared by cutting at 10 µm thickness using Reichert Sliding Microtome while roots were embedded through standard procedures. The results showed that morphologically, rhizomes in P. acanthoneura, P. atrovirens, P. mildbraedii, P. togoensis and P. similis were erect to sub erect, but rhizomes were short creeping in P. ensiformis and P. vittata. The anatomy of the rhizomes showed a typical dictyostele pattern with variable number of leaf gaps, while roots of all the Pteris species were the diarch type with two xylem bundles alternating with two phloem bundles. The morphological and anatomical structures of the rhizomes and the roots provide useful specific distinctions of taxonomic importance for the genus Pteris and the family Pteridaceae.

The spliceophilin CYP18-2 is mainly involved in the splicing of retained introns under heat stress in Arabidopsis.

Peptidyl-prolyl isomerase-like 1 (PPIL1) is associated with the human spliceosome complex. However, its function in pre-mRNA splicing remains unclear. In this study, we show that Arabidopsis thaliana CYCLOPHILIN 18-2 (AtCYP18-2), a PPIL1 homolog, plays an essential role in heat tolerance by regulating pre-mRNA splicing. Under heat stress conditions, AtCYP18-2 expression was upregulated in mature plants and GFP-tagged AtCYP18-2 redistributed to nuclear and cytoplasmic puncta. We determined that AtCYP18-2 interacts with several spliceosome complex BACT components in nuclear puncta and is primarily associated with the small nuclear RNAs U5 and U6 in response to heat stress. The AtCYP18-2 loss-of-function allele cyp18-2 engineered by CRISPR/Cas9-mediated gene editing exhibited a hypersensitive phenotype to heat stress relative to the wild type. Moreover, global transcriptome profiling showed that the cyp18-2 mutation affects alternative splicing of heat stress-responsive genes under heat stress conditions, particularly intron retention (IR). The abundance of most intron-containing transcripts of a subset of genes essential for thermotolerance decreased in cyp18-2 compared to the wild type. Furthermore, the intron-containing transcripts of two heat stress-related genes, HEAT SHOCK PROTEIN 101 (HSP101) and HEAT SHOCK FACTOR A2 (HSFA2), produced functional proteins. HSP101-IR-GFP localization was responsive to heat stress, and HSFA2-III-IR interacted with HSF1 and HSP90.1 in plant cells. Our findings reveal that CYP18-2 functions as a splicing factor within the BACT spliceosome complex and is crucial for ensuring the production of adequate levels of alternatively spliced transcripts to enhance thermotolerance.

Influence of drought stress and foliar application of chitosan on nutrient accumulation and phenolic composition of Thymus daenensis Celak

AbstractChanges in climate have intensified the drought in semi‐arid regions. A shift toward cultivation of low‐input crops, including high‐value medicinal and herbal plants seems a more sustainable alternative strategy. A 2‐year field study was conducted to investigate the influence of drought stress and chitosan on nutrient density and phenolic compounds of thyme. Treatments consisted of a factorial combination of three irrigation and three chitosan rates. Irrigation treatments consisted of keeping experimental plots at field capacity (no stress), irrigation when plots reached 50% of field capacity (mild stress), and irrigation when plots reached 25% of field capacity (severe stress). Chitosan rates were 0, 200, and 400 μL L−1, while K+, and to some degree Ca+2, accumulation increased by drought, N, P, and all micronutrients (Mn2+, Zn2+, Cu2+, and Fe2+) decreased steadily as drought stress intensified. Drought stress reduced N and P by 23%–19% and 35%–23%, respectively, over the 2 years. Application of chitosan enhanced the accumulation of macro and micronutrients. Drought stress resulted in alterations in phenolic composition. In mature plants, almost all phenolic compounds, except thymol, increased as drought stress intensified. Cinnamic acid and rosmarinic contents, as the two major identified compounds, increased by 31% and 45%, respectively, under severe drought. Similar to drought, chitosan elicitation was more effective in elevating phenolic compounds in mature plants. The response of thyme to chitosan was independent of soil moisture availability. The results indicated that application of 400 μL−1 chitosan improved nutrient density and dry matter while significantly saved irrigation water.

Positive Effect Induced by Plasma Treatment of Seeds on the Agricultural Performance of Sunflower

The need for efficient technologies to enhance productivity in agriculture strongly motivates research on plasma treatment of seeds and plants. In this study, the influence of plasma treatment on sunflower (Helianthus annuus L.) seeds was evidenced throughout the entire life span of the plants. The seeds were packed in a DBD reactor operated in air and treated in plasma for 10 min, using a sinusoidal voltage of 16 kV amplitude at 50 Hz frequency. Early growth observation of plants under laboratory conditions showed that, after a slower start, the plasma-treated seeds developed faster and produced taller seedlings with greater total mass as compared to the control samples. Results obtained from mature plants cultivated in the field revealed a positive effect of plasma exposure with respect to capitulum size, number of seeds per capitulum and mass per thousand seeds, resulting in a remarkable increase in crop yield. The plasma effect lasted for at least two weeks of seed storage; however, it was considerably affected by the sowing period.

Identification of naturally occurring atoxigenic strains of Fusarium verticillioides and their potential as biocontrol agents of mycotoxins and ear rot pathogens of maize

Pre-harvest infection of seed with either of two major ear rot pathogens of maize, Fusarium verticillioides and Aspergillus flavus, leads to high economic losses and detrimental health effects to humans and animals through the production of mycotoxins, fumonisin and aflatoxin, respectively. These carcinogenic compounds are some of the most agriculturally important mycotoxins, consumption of which can lead to various cancers and stunted growth. While atoxigenic strains of A. flavus are used for biocontrol of aflatoxin, no similar biocontrol agent exists for F. verticillioides. We hypothesized that fumonisin non-producing (atoxigenic) F. verticillioides may competitively exclude or antagonize A. flavus and promote plant growth. We screened 150 isolates of Fusarium spp. collected from maize across Texas and identified several F. verticillioides isolates that did not produce fumonisin either in vitro or when grown on maize kernels. Atoxigenic strains of F. verticillioides, 302-A6 and PAL 401, variably affected plant growth following seed coating or soil injection. When pre-applied in a kernel bioassay, both strains significantly inhibited aflatoxin contamination compared to kernels later inoculated only with A. flavus. Applied as a seed coating, neither isolate inhibited aflatoxin or fumonisin accumulation in mature plants. Results confirmed that fumonisin is not required for virulence in Fusarium stalk rot infections. Application of F. verticillioides 302-A6 to developing ears reduced fumonisin accumulation by naturally-occurring toxigenic strains of F. verticillioides. This atoxigenic strain of F. verticillioides and others need to be further investigated to prove their efficacy and potential use as atoxigenic biocontrol agents to reduce fumonisin risk in corn.

Comparative Transcriptomics Profiling of Perennial Ryegrass Infected with Wild Type or a ΔvelA Epichloë festucae Mutant Reveals Host Processes Underlying Mutualistic versus Antagonistic Interactions

Epichloë species form bioprotective endophytic symbioses with many cool-season grasses, including agriculturally important forage grasses. Despite its importance, relatively little is known about the molecular details of the interaction and the regulatory genes involved. VelA is a key global regulator in fungal secondary metabolism and development. In previous studies, we showed the requirement of velA for E. festucae to form a mutualistic interaction with Lolium perenne. We showed that VelA regulates the expression of genes encoding proteins involved in membrane transport, fungal cell wall biosynthesis, host cell wall degradation, and secondary metabolism, along with several small-secreted proteins in Epichloë festucae. Here, by a comparative transcriptomics analysis on perennial ryegrass seedlings and mature plants, which are endophyte free or infected with wild type (mutualistic interaction) or mutant ΔvelA E. festucae (antagonistic or incompatible interaction), regulatory effects of the endophytic interaction on perennial ryegrass development was studied. We show that ΔvelA mutant associations influence the expression of genes involved in primary metabolism, secondary metabolism, and response to biotic and abiotic stresses compared with wild type associations, providing an insight into processes defining mutualistic versus antagonistic interactions.

Plantation understorey legume functional groups enhance soil organic carbon sequestration by promoting species richness

AbstractDespite evidence showing that plant diversity or tree mixtures increase carbon storage in experimental grasslands or mixed forests, the effects of understorey plant communities on changes in soil organic carbon (SOC) storage in planted forests remain unclear, especially for monoculture plantations. Therefore, based on field observations in monoculture plantations on the Loess Plateau in China, we investigated the direct effects of understorey species richness (USR) and plantation age on SOC storage, and identified the indirect effects of understorey legume species richness (ULSR) and soil moisture (SM) mediated by USR. Results indicated that plantation age and USR significantly increased SOC sequestration with almost equal effects. The changes in the relationship between USR and SOC storage varied along the water availability gradient, from significantly positive (in plots with SM ≤11.14%) to insignificant (in plots with SM >11.14%). We observed that ULSR could increase SOC sequestration by promoting USR, while SM had negative and positive effects on ULSR and USR, respectively. Our findings can provide insights into plantation management in semiarid regions: Thinning mature plantations and introducing understorey legumes can increase SOC sequestration and maintain water resource sustainability.

Phytochemical, Antimicrobial and Cytotoxic Activities of Strophanthus sarmentosus DC

Strophanthus sarmentosus DC is used traditionally in the management of snake-bite, arthritis, eye infection, rheumatism, emetic and venereal diseases. Freshly collected mature Strophanthus sarmentosus plant parts were air-dried at room temperature. Each of the plant parts (leaf, stem and roots) was successively extracted by cold extraction method using hexane, ethyl acetate and methanol respectively. The crude extracts were subjected to phytochemical, antimicrobial and cytotoxicity analysis by employing chemical tests, agar diffusion and brine shrimps methods.The phytochemical screening showed the presence of tannins, saponins, glycosides, flavonoids, phenols, steroids, terpenoids and carbohydrates in all the extracts. The extracts demonstrated broad spectrum activities against both gram- positive and gram-negative bacteria and the fungi tested. The MIC and MMC of ethyl acetate and methanol extracts of the S. sarmentosus (stem) is between 0.3 and 5.0 mg/mL. The cytotoxic activity (LC50) of the S. sarmentosus extracts (leaf, stem and root) ranged between 117 µg/mL and 270 µg/mL, showing that the extracts are within the medium toxic level according to Clarkson’s toxicity index.

Carbon Stocks in Vegetation and Soil and Their Relationship with Plant Community Traits in a Mediterranean Non-tidal Salt Marsh

Salt marshes are considered among the ecosystems with the highest capacity for carbon sequestration. However, studies have mainly focused on tidal salt marshes, while knowledge about non-tidal salt marshes, which prevail in the Mediterranean Basin, is currently scarce. Consequently, we aimed to (1) estimate the carbon stocks of the vegetation, litter, and soil of three natural Habitats of Community Interest of a Mediterranean non-tidal salt marsh–a halophilous scrub, a salt meadow, and a glasswort sward–and (2) determine how differences in floristic composition and community structure among habitats over 1 year are related to the amount and distribution of carbon stored in plants and soils. Results show that the halophilous scrub and the salt meadow were constituted by mature plant communities with overall stable carbon stocks in the vegetation, litter, and soil (0–20 cm), which were approximately 4 and 2.5 times larger, respectively, than those found in the glasswort sward (1013 ± 40 g C m−2). However, while the salt meadow and the glasswort sward had more carbon stored in the soil than in the vegetation (approximately 3 and 7.5 times more, respectively), the halophilous scrub had similar amounts in both compartments (2248 ± 388 and 1566 ± 179 g C m−2 in the soil and vegetation, respectively). Sarcocornia fruticosa represented 93.5% of the total plant biomass of the halophilous scrub, which highlights the importance of this species in maintaining carbon stocks in this Mediterranean non-tidal salt marsh.

Soil microbiota impact on Boletus edulis mycelium in chestnut orchards of different ages

Biotic factors (host plant age and soil microbiota) influencing Boletus edulis mycelium frequency and concentration have been investigated. The study was carried out in September, October and November 2018 and 2020, using six orchards of chestnut hybrid Castanea × coudercii of 40-, 10- and 3-years-old. Taxonomical identity of bacterial and fungal species was ascertained by DNA metabarcoding. Mycelium frequency and concentration of B. edulis were studied through quantitative PCR (qPCR) of soil samples. It was hypothesized that mature plants (40-years-old) have a greater soil microbiota associated at the rhizosphere, in comparison with young plants (10- and 3-years-old). This situation may reverberate on B. edulis mycelium that should be more abundant in 40-years-old orchards, also thanks to the higher number of beneficial interactions whit soil microbiota. It was found that host plant age significantly altered bacterial and fungal assemblages in both years. Bacterial fraction was dominated by the phylum Proteobacteria, Acidobacteria and Actinobacteria and showed a higher species richness and diversity in orchards of 10- and 3-years-old. Fungal phylum such as Basidiomycota was more abundant in 40- and 10-years-old orchards, whereas Ascomycota and Mortierellomycota were more abundant in the 10- and 3-years-old orchards. Mycelium frequency of B. edulis in soil samples was higher in 2020 (97 %) than in 2018 (19 %), although without differences between plant age and sampling month in each year. Boletus edulis mycelium concentration was higher in 2020 than in 2018, and in September 2020, whereas plant age did not have any effect. Of 173 bacterial taxa considered, the 12 %, 54 % and 82 % of the significant correlations with B. edulis mycelium concentration were found in 40-, 10- and 3-years-old orchards, respectively. On the other hand, of 180 fungal taxa, the 12 %, 24 % and 42 % of the significant correlations occurred in 40-, 10- and 3-years-old orchards, respectively. This investigation represents the first report about the role of soil microbiota on the ecology of B. edulis in Castanea agro-ecosystem.

Spectral Discrimination of Macronutrient Deficiencies in Greenhouse Grown Flue-Cured Tobacco

Remote sensing of nutrient disorders has become more common in recent years. Most research has considered one or two nutrient disorders and few studies have sought to distinguish among multiple macronutrient deficiencies. This study was conducted to provide a baseline spectral characterization of macronutrient deficiencies in flue-cured tobacco (Nicotiana tabacum L.). Reflectance measurements were obtained from greenhouse-grown nutrient-deficient plants at several stages of development. Feature selection methods including information entropy and first and second derivatives were used to identify wavelengths useful for discriminating among these deficiencies. Detected variability was primarily within wavelengths in the visible spectrum, while near-infrared and shortwave-infrared radiation contributed little to the observed variability. Principal component analysis was used to reduce data dimensionality and the selected components were used to develop linear discriminant analysis models to classify the symptoms. Classification models for young, intermediate, and mature plants had overall accuracies of 92%, 82%, and 75%, respectively, when using 10 principal components. Nitrogen, sulfur, and magnesium deficiencies exhibited greater classification accuracies, while phosphorus and potassium deficiencies demonstrated poor or inconsistent results. This study demonstrates that spectral analysis of flue-cured tobacco is a promising methodology to improve current scouting methods.

Performance of chickpea (Cicer arietinum) under different land configurations, irrigation methods and schedules in sandy-loam soil

A field study was carried out during the winter (rabi) season of 2017–18 at the Govind Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttarakhand, to study the effect of different land configurations, irrigation methods and schedules on growth, yield and economics of chickpea (Cicer arietinum L.). The results revealed that at maturity stage, plant height, branches/plant and 100-grain weight increased significantly in raised bed over flat-bed method of sowing. Plant dry-matter, pods/plant, grain weight/plant, grain and straw yields and net return and benefit: cost (B : C) ratio did not differ significantly due to land configuration treatment. Sprinkler irrigation resulted significant increase in growth characters (plant height, branches/plant and total plant dry-matter accumulation) and yield attributes (pods/plant, 100-grain weight and grain weight/plant), grain and straw yields and net return and B : C ratio as compared to check basin irrigation. Combination of sprinkler irrigation method and flat-bed sowing resulted in the highest grain yield (1,325 kg/ha). Under check basin irrigation, raised bed provided 7.8% higher grain yield than flat-bed method of sowing (1,083 kg/ha). Two irrigations at vegetative and pod-development stages resulted in significantly higher plant height, branches/plant, total dry-matter accumulation/plant, pods/ plant, grain weight/plant, grain yield and higher net returns and B : C ratio than single irrigation at either stage.

Effects of eustress induced by low concentrations of salinity on broccoli (<i>Brassica oleracea</i>) and purslane (<i>Portulaca oleracea</i>) microgreens

Most controlled environments utilize municipal water for crop irrigation. Many of these sources exceed the EPA guidelines of &lt;500 mg L⁻¹ total dissolved salts. Issues can arise when tap water with above limit salt concentrations is used for irrigation. Eustress is defined as the use of slight stress (from stressors such as salinity, temperature, or light) to induce positive effects without distress. While eustress is commonly used on mature plants, the effects on early growth stages of plants, such as microgreens, are not well documented. As microgreens are typically more stress sensitive, the concentrations of salinity to induce eustress may be lower than for mature plants. To identify how eustress affects microgreens, salinity concentrations commonly found in tap water were used in these experiments. <italic>Brassica oleracae</italic> (moderately salt tolerant) and <italic>Portulaca oleracea</italic> (highly salt tolerant) microgreens were evaluated. Both species of microgreens were cultivated using salinity irrigation treatments ranging from 0 dS m⁻¹ to 1.5 dS m⁻¹. Plants were analyzed for microgreen yield (fresh weight and dry weight), percent moisture content (%MC), percent dry matter (%DM), vitamin C (T-AsA, AsA) and proline concentrations. The results indicate that yields of both variety remained unaffected by the salinity treatments. However, %MC and proline significantly increased under 1 dS m⁻¹ and 1.5 dS m⁻¹ NaCl in broccoli. Vitamin C also decreased as salinity increased in broccoli microgreens. Purslane microgreen vitamin C and proline remained unaffected by salinity. In conclusion, while low salinity levels had no negative impacts on microgreen yields, there were varied impacts on the phytochemistry between each variety.

Analysis of Milorganite’s ability to sustain growth of Ocimum basilicum in simulated Martian soil

In years to come, it will be important to discover if life on Mars is a realistic option. As the population continues to grow and resources begin to dwindle, the possibility of colonizing other planets gives hope to humankind that extinction may be avoidable. Previous research suggests that some types of plants are able to survive the harsh conditions on Mars. This research aimed to discover if Milorganite could improve the growth of Ocimum basilicum (basil) in simulated Martian soil. Milorganite is a waste product-based fertilizer that was chosen to simulate the fecal matter of astronauts in space. We observed that basil could not grow in the simulated soil across all concentrations of Milorganite. We then shifted the study toward transplanting mature basil plants into the same soil with differing amounts of Milorganite. During the experiment, we observed that higher concentrations of Milorganite killed the basil plants. However, results were insignificant, suggesting that Milorganite has no effect on the growth of basil in simulated Martian soil. We watered some plants with a Miracle-Gro mixture water and some with tap water to ensure the type of water wasn’t interfering with the results of the Milorganite. The Miracle-Gro did not significantly improve the conditions of the soil across all levels of Milorganite.

STANDARDIZATION OF MICROPROPAGATION TECHNIQUE OF MULBERRY (MORUS ALBA L.)

A standardization of protocol for rapid multiplication of mulberry (Morus alba L.) was established in vitro using nodal explant excised from hydroponically grown mature mulberry plants. Shoot initiation was induced on Murashige and Skoog (MS) medium supplemented with different concentrations of (BAP) 6- Benzyl amino purine. Effect of different concentration of 6- Benzyl amino purine was studied on multiplication of shoot, revealed that elongated shoots (2-3 cm) were cultured on half strength MS medium supplemented with (IBA) indole-3-butyric acid. Higher percentage of shoot initiation (90%) was observed on MS medium supplemented with 2 mg/l 6-bezyl amino purine. Initiated shoots gave a higher average number of shoots and elongation was observed when it was subcultured on MS medium supplemented with 1.4 mg/l 6-bezyl amino purine. A maximum percentage of root formation (70%) was observed when elongated shoots were subcultured on half strength MS medium containing 1.3 mg/l indole-3-butyric acid. Rooted plants transferred to pots containing sterile FYM, garden soil and sand (1:1:1) for acclimatization in green house showed (75%) survival capacity.

Estimation of Vegetation Indices With Random Kernel Forests

Vegetation indexes help perform precision farming because they provide useful information regarding moisture, nutrient content, and crop health. Primary sources of those indexes are satellites and unmanned aerial vehicles equipped with expensive multispectral sensors. Reducing the price of obtaining such information would increase the availability of precision farming. Several studies have proposed deep neural network methods to estimate the indexes from RGB color images. However, these studies report relatively large errors for mature plants, when highly non-linear relationships between image RGB bands and vegetation indexes arise. One could apply multilayer random forest-based models (Deep Forests) to solve this problem, but they have limited discriminative power and ability on catching non-linear relationships between image features. The cornerstone of the Deep Forests is that at each layer they enrich original features with embeddings containing empiric class probabilities from previous layers, although these probabilities deliver limited information. In this paper, we propose methods, which combine ideas of Deep Forests, Random Forests of multivariate trees, and global pruning of Random Forests to tackle these problems. We applied oblique (linear) and kernel (non-linear) trees as basic classifiers of the Deep Forest to improve discriminative power. We also utilized a method to refine Random Forests with a global loss optimization. This method helps to generate more expressive embeddings at each layer of the Deep Forest, which significantly improves results of the data analysis. In the experiments, we compared those methods with AlexNet and ResNet-based neural networks on several image classification datasets as well as on the NDVI prediction task. The experiments on image classification show that the proposed Deep Forest-based methods provide competitive results on datasets with small and medium size of feature-set. The results of the NDVI prediction task indicate that these methods are robust to senescence of plants and outperform neural network-based solutions.