Stem Dry Weight Research Articles

Effect of Different Mulches on Growth and Yield of Cauliflower in Southern Bangladesh

A field experiment was conducted at the research farm of Patuakhali Science and Technology University (PSTU), Patuakhali from November 2011 to April 2012 to find out the most adventitious mulch material for Cauliflower production. The experiment was laid out in Randomized Complete Block Design (RCBD) with four replications. Six different mulches (M) along with control were applied as treatment viz M0 =Control (without mulches), M1 =Black polythene, M2 =White polythene, M3 =Saw dust, M4 =Water hyacinth and M5 =Rice straw. Data were compared on plant height (cm); number of leaves/plant; leaf area (cm2)/plant; leaf area index (cm2); dry weight of root, leaf and stem (g/plant); total dry matter (g/plant); crop growth rate (g/m2/day); relative growth rate (g/cm2/day); diameter of curd (cm2); curd fresh weight (g/plant) and curd yield (t/ha). Significant variation was obtained in case of all the compared parameters among the treatments but water hyacinth mulch gave highest value compared to control and other mulches. Finally, it can be concluded that water hyacinth mulch was found most effective for cauliflower production under AEZ-13 of the southern part of Bangladesh.
 Environ. Sci. & Natural Resources, 13(1&2): 110-117, 2020

Correlation and path analysis studies in kharif sorghum (Sorghum bicolor L. Moench) inbred lines

The present investigation was studied in fourteen inbred lines of kharif sorghum (Sorghum bicolor L. Moench) hybrids. The experiment was laid out in randomized block design with three replications at Sorghum Research Station, Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani during kharif 2021. Fifteen yield contributing traits were evaluated for correlation and path analysis studies in fourteen genotypes. In present investigation there is existence of higher genotypic correlation when compared to phenotypic correlation that indicates the presence of inherent association among the characters. Significant and positive association was observed between grain yield and its yield contributing traits like stem dry weight, relative water content, SPAD, total chlorophyll content , fodder yield and harvest index at both genotypic and phenotypic level. In this investigation path analysis revealed at both genotypic and phenotypic level for plant height, leaf dry weight, relative water content, SPAD, total chlorophyll content, grain no per panicle, fodder yield and harvest index exhibited positive direct effect on grain yield there by it would play an important role in selection criteria for improving the character grain yield. Among the fourteen genotypes studied inbred lines viz. SPV 2504, CSV 27, CSV 31, CSV 39 and PVK 1025 recorded better performance and these are considered as the superior genotypes.

Application of gamma irradiation on morphological, biochemical, and molecular aspects of wheat (Triticum aestivum L.) under different seed moisture contents

Nuclear technology is currently used as a tool in mutation breeding to improve crops by increasing genetic variation. The ionization of gamma rays produces large amounts of free radicals, simulating stressors in the natural environment. To avoid gamma-ray-induced oxidative stress, plants use antioxidant defense systems. Exposure of plants to irradiation can affect the germination, growth, and production of metabolites. Plants' sensitivity to irradiation depends on genetic and environmental factors such as moisture content. For this purpose, the effects of different gamma irradiation doses [0, 100, 200, 300, and 400 Gray (Gy)] and different seed moisture contents (7, 13, and 19%) on traits such as seed germination, seedling growth, molecular and biochemical alterations in antioxidant enzymes were examined in the current study. Based on the results, the highest seed germination percentage was observed in the interaction effect of seed moisture at 13% with an irradiation dose of 400 Gy (98.89%). Seedling survival percent and seedling length decreased with increasing doses of gamma irradiation at different seed moisture contents. Increasing gamma irradiation doses were reduced root and stem fresh and dry weight, and root and stem length. The highest level of catalase enzyme activity and expression was observed at 200 and 300 Gy irradiation doses at different moisture contents. The peroxidase and polyphenol oxidase gene expression were reduced at all contents of gamma irradiation doses and seed moisture compared to the control. It can be concluded that the dose of 200–300 Gy of gamma irradiation reduced plant growth by 30% in terms of fresh and dry weight and length of plants, as well as enhanced the expression of antioxidant enzymes. The results of this study could help plant breeders select an appropriate dose rate in wheat for further research.

Annual Herbaceous Plants Exhibit Altered Morphological Traits in Response to Altered Precipitation and Drought Patterns in Semiarid Sandy Grassland, Northern China.

The frequency and intensity of extreme precipitation events and severe drought are predicted to increase in semiarid areas due to global climate change. Plant morphological traits can reflect plant responses to a changing environment, such as altered precipitation or drought patterns. In this study, we examined the response of morphological traits of root, stem, leaf and reproduction meristems of annual herbaceous species to altered precipitation and drought patterns in a semiarid sandy grassland. The study involved a control treatment (100% of background precipitation) and the following six altered precipitation treatments: (1) P(+): precipitation increased by 30%, (2) P(++): precipitation increased by 60%, (3) P(-): precipitation decreased by 30%, (4) P(--): precipitation decreased by 60%, (5) drought 1 (D1): 46-day drought from May 1st to June 15th, and (6) drought 2 (D2): 46-day drought from July 1st to August 15th. P(++) significantly increased root length, flower length-to-width ratio, both P(+) and P(++) significantly increased stem length and flower number in the plant growing seasons, while all of them decreased under P(-) and P(--). The annual herbaceous plants marginally increased the number of second-level stem branches and stem diameter in order to better resist the severe drought stress under P(--). P(+) and P(++) increased the root, stem, leaf, and flower dry weight, with the flower dry weight accounting for a larger proportion than the other aboveground parts. Under D2, the plants used the limited water resources more efficiently by increasing the root-to-shoot ratio compared with P(-), P(--) and D1, which reflects biomass allocation to belowground increased. The linear mixed-effects models and redundancy analysis showed that the root-to-shoot ratio and the dry weight of various plant components were significantly affected by morphological traits and altered precipitation magnitude. Our results showed that the herbaceous species have evolved morphological trait responses that allow them to adapt to climate change. Such differences in morphological traits may ultimately affect the growing patterns of annual herbaceous species, enhancing their drought-tolerant capacity in semiarid sandy grassland during the ongoing climate change.

High source–sink ratio at and after sink capacity formation promotes green stem disorder in soybean

Green stem disorder (GSD) of soybean is characterized by delayed leaf and stem maturation despite normal pod maturation. Previous studies have suggested that GSD occurrence is promoted by a high source–sink ratio, which is produced by thinning or shade removal at the R5 growth stage (the beginning of seed filling). Here the effects of different times and durations of shade removal after the R5 stage on GSD severity were analyzed. First, shade removal for more than 28 days after R5 increased GSD severity by more than 0.4 point in GSD score. Thinning treatment at R5 increased specific leaf weight by 23%, suppressed stem dry weight reduction, and upregulated 19 genes including those encoding vegetative storage proteins at R5 + 28d, indicating excess source ability relative to sink size. On the contrary, shade removal for 14 days after R5 decreased GSD severity by 0.5 point in GSD score. In this treatment, seed size was smaller, while seed number was significantly larger than control, suggesting that shortage of source ability relative to sink size. These results implied that soybean plants regulate GSD occurrences either positively or negatively according to a source-sink ratio during the R5 to R5 + 28d growth stages.

The effect of olive pomace and seaweed extract on the growth of pepper seedling

In recent years, environmental pollution problems have increased due to organic wastes. The use of organic wastes as fertilizer plays an important role in reducing environmental pollution and improving the physical, chemical and biological properties of the soil. This study was carried out to determine the effect of unprocessed olive pomace (OP) which is a by-product of olive oil industry and seaweed (SW) on the growth of pepper seedlings. In the study, 4 different pomace ratios (5% OP + 95% peat, 10% OP + 90% peat, 15% OP + 85% peat and 20% OP + 80% peat V:V) and 4 different SW extract doses ( 0% 0.5%, 1% and 2% ) were used. In the study, parameters such as plant height, stem diameter, leaf area, plant fresh and dry weights, and chlorophyll index were investigated. According to the results of the study, OP applications significantly decreased the stem diameter, leaf area, leaf number, leaf dry weight, stem dry weight, root dry weight, chlorophyll content, stem-root ratio and total plant dry weight, while root length increased. On the other hand, SW applications had no an important effect on plant growth but partially imporoved in the zero OP application.

​​Forage Yield Potential and Adaptation Performance of Alfalfa Genotypes in Acidic Soil Condition of Southwestern Ethiopia

Background: The adaptability and forage yields of some alfalfa varieties are very low compared to the other varieties. Thus, this experiment was conducted to evaluate the adaptability, forage yield potential and farmers’ preference of seven alfalfa genotypes across two agro-ecological conditions of Chena and Gimbo districts, Southwestern Ethiopia in the year 2019 and 2020. Methods: Seven varieties of alfalfa forage including Magna 788, Magna 801, FL-L77, Hunter river, FG9-09, FG10-09 and Pioneer 1995 were used as experimental treatments. The genotype was arranged using an RCBD with three replications. All the relevant data were collected and then subjected to SAS software. To assess the adaptability and productivity potential of the selected varieties, all necessary data were recorded. Result: The effect of varieties on adaptation performance and yield potential showed significant differences (P≤0.05) for all parameters except the date of emergence at both locations. Dry matter yield, biomass yield, leaf weight and stem weight were significantly (P≤0.01) affected among all varieties of alfalfa. Therefore, all varieties of Alfalfa were found to be adaptable and performed well for most growth parameters and yield components except seed production under the conditions of Gimbo and Chena agroecology.

Combined Application of Organic and Inorganic Amendments Improved the Yield and Nutritional Quality of Forage Sorghum

The use of organic amendments is seen to be a promising method for enhancing crop productivity and soil health. Therefore, this study was performed for two consecutive years (2019 and 2020) to determine the effects of organic biochar (BC), sugar industry press mud (MUD), and poultry manure (PM) combined with inorganic amendments on the yield and nutritional quality of forage sorghum at the College of Agriculture, Bahauddin Zakariya University, Bahadur sub-campus, Layyah, Pakistan. The treatments were comprised of the following: control (no inorganic or organic amendments added); recommended dose of NPK (59:72:30 kg ha−1); half dose of NPK (29.5:36:15 kg ha−1); recommended dose of poultry manure (PM) at 5 t ha−1; recommended dose of press mud (MUD) at 40 t ha−1; recommended dose of biochar (BC) at 11 t ha−1; BC + half NPK; MUD + half NPK; PM + half NPK; PM + BC + half NPK; PM + MUD + half NPK; BC + MUD + half NPK; PM + BC + MUD + half NPK. The treatments were carried out in a triplicate randomized complete block design. Results revealed that combined application of PM + BC + MUD + 1/2 NPK significantly enhanced the plant height (201 cm), number of leaves (17), stem diameter (18 mm), stem dry weight (201.7 g), leaf dry weight (30.4 g), leaf area (184.3 cm2), green forage yield (31.8 Mg ha−1), and dry biomass yield (12.7 Mg ha−1) compared with the control treatment. Forage quality traits, including crude protein (CP), brix percentage, acid detergent fiber (ADF), and acid detergent lignin (ADL), showed maximum value with the combined application of PM + BC + MUD + 1/2 NPK. ADF and ADL are linked with lower digestibility; therefore, it was concluded that the combined application of PM + BC + MUD + 1/2 NPK can improve the productivity, dry biomass yield, and CP of sorghum, but reduces the digestibility under semi-arid conditions, such as those in Central Pakistan.

Suitable varieties and high-yielding population characteristics of late season rice in the northern margin area of double-cropping rice along the Yangtze River

<p id="C2">To clarify the suitable types of rice varieties and the mechanism of high yield formation, we mainly analyzed the yield difference between<italic> indica</italic> and <italic>japonica</italic> rice in late season in the northern margin of the double-cropping rice along the Yangtze River. The experiment was conducted from 2018 to 2019 in Lujiang, Anhui province. The differences of yield and yield components, dry matter accumulation, and growth period between <italic>indica</italic> and <italic>japonica</italic> rice were compared and analyzed through 17 <italic>indica</italic> rice and 17 <italic>japonica</italic> rice varieties (strains) which were cultivated in this local area. The results showed that the overall yield level of <italic>japonical</italic> rice was similar to that of <italic>indica</italic> rice. However, compared with <italic>indica</italic> rice, the<italic> japonica</italic> rice had the characteristics of fewer yield-limiting factors, superior safety of panicle fullness, higher yield stability, and ecological safety. High-yield <italic>japonica</italic> rice mainly increased the total dry matter accumulation from transplanting to heading stage so as to improve total spikelets and yield. The effects of dry matter accumulation at different stage with different panicle types on total spikelets were quite different. Among them, the dominance period of dry matter accumulation of medium-large panicle (102.3-112.0 grains per panicle) and small panicle <italic>japonica</italic> rice (52.0-99.7 grains per panicle) are transplanting to panicle differentiation and panicle differentiation to heading stage respectively and the correlation coefficients with total spikelets were 0.709 and 0.829, respectively. Further analysis revealed that dry matter accumulation during transplanting to panicle differentiation stage of large panicle <italic>japonica</italic> rice was significantly affected by the number of tillers at tillering stage, while the dry matter accumulation during panicle differentiation to heading stage of small panicle <italic>japonica</italic> rice was affected by the number of tillers and dry weight of single stem at heading stage. In summary, this study suggested that <italic>japonica</italic> rice was a suitable late season rice variety in the northern margin area of double-cropping rice along the Yangtze River. The number of spikelets in the high-yielding <italic>japonica</italic> rice was 33.8×10³-41.0×10³ m^-2, the dry matter accumulation at maturity was 15.2-16.6 t hm^-2, and the daily yield was 58.9-64.3 kg hm^-2 d^-1. Regarding the selection of varieties, high-yield large-panicle <italic>japonica</italic> rice, such as Jia 58, Wuyujing 6571, and Changyou 5, should have strong tillering ability; while small-panicle rice varieties, such as Ningjing 7, Wuyujing 5745 and Huxiangjing 151, should have a suitable number of tillers at heading stage and dry weight of single stem. In addition, it was necessary to study the optimized cultivation techniques for high-yielding <italic>japonica</italic> rice varieties with different panicle types in order to further develop the yield potential.

Ability of Urtica dioica L. to adsorb heavy metals (Pb, Cd, As, and Ni) from contaminated soils

ABSTRACT Landfill leachate contains heavy metals that contaminate water and soil near the landfill site. Phytoremediation is a process of decontaminating soil or water by using native plants to adsorb and accumulate or break down pollutants. This study aimed to evaluate absorption and accumulation of heavy metals from simulated landfill soil by nettle. Nettle seeds were collected from the Tonekabon landfill site and planted in 243 pots. After reaching the 6-leaf stage, the plants were exposed to three concentrations of four heavy metals (Pb, Cd, As, and Ni) during the growing season. An atomic absorption spectrometer was used to measure the concentrations of the heavy metals in nettle plants and the morphological features of nettle fibers. The results showed that increases in the concentrations of the heavy metals in the soils led to their higher concentrations in all organs of the nettle plants (Pb> Ni> Cd> Ar), and larger quantities of the heavy metals were accumulated in the aerial parts of the plants. In parallel with this result, the dry weights of stem, leaf and root, and leaf area index also decreased. Values of TF> 1 and BAC <1 in plant organs showed the ability of nettle to accumulate more heavy metals when they were present at higher concentrations in the soil. Bioremediation using native plants for removal of heavy metals from soil and their accumulation in these plants is a low-cost and environmentally friendly technology. Nettle is a plant that grows wild in the landfills in northern Iran and, due to its ability to accumulative heavy metals in its organs, is a suitable plant species for their removal from soil.

Genetic Variation and Genetic Advance of Three Elite Cassava (Manihot Esculenta Crantz) Clones Under Wet Dry Climate of Lampung

Waxy cassava having high amylopectin content could contribute and increase genetic background. Unfortunately, the genetic parameter information of three elite cassava clones as Waxy, UJ-5, and BW-1 is still limited. Consequently, the objective of this study was to evaluate the genetic variation and genetic advance of three cassava clones. This study was conducted on the Integrated Field Lab of Lampung from December 2019 to October 2020. Treatment was arranged by a single factor in RCBD with two replications. There were three cassava genotype clones, as Waxy, UJ-5 (originally Kasetsart), and BW-1 (originally Huay Bong-60). Genetics parameters were analyzed by using Minitab programs (Version 17). Variables observed were plant height, leaf number, attached leaf number, internode number, root number, tuber number, tuber fresh weight, tuber dry weight, stem dry weight, attached leaf dry weight, petiole dry weight, starch content, starch weight, and harvest index. The results showed that most variables had high genetic variation and heritability value except for starch content. Starch content showed a medium heritability value as 50%. Moreover, the genetic advance of starch content and weight were 14 and 18%, respectively. It could be concluded that an environmental factor influenced starch content.

Effects of the amount of biochar application on agronomic traits and nutrient content of soybean

A pot experiment was conducted at the Shaoyang University test base in May 2020, with Xudou 18 as the research object. We investigated the growth and development as well as the agronomic traits and nutrient content across a gradient of 0 (CK), 5, 10, 20, and 40 g·kg-1 of biochar addition. The results showed that compared with CK, the biochar application significantly affected growth dynamic, plant height, number of effective pods per plant, 100-grain weight, and leaf and stem dry weights of soybean plants, and the contents of protein, crude fat and isoflavone in soybean seeds. At the application rate of 20 g·kg-1, the germination rate of soybean was the highest, the growth period was the shortest, the number of effective pods per plant was the highest, the 100-grain weight was the largest, and the contents of protein, crude fat, and isoflavone were the highest in the seeds. When biochar application reached 40 g·kg-1, the plant height of soybean was the highest with extended vegetative growth and delayed maturity, whereas the effective pods per plant and 100-grain weight was reduced compared to that with 20 g·kg-1 application. In conclusion, the effects of biochar addition on agronomic traits and nutrient content of soybean varied with application amount, with 20 g·kg-1 being the optimal under the test condition.

Individual and Interactive Effects of Multiple Abiotic Stress Treatments on Early-Season Growth and Development of Two Brassica Species

Potential global climate change-related impacts on crop production have emerged as a major research priority and societal concern during the past decade. Future changes, natural and human-induced, projected in the climate have implications for regional and global crop production. The simultaneous occurrence of several abiotic stresses instead of stress conditions is most detrimental to crops, and this has been long known by farmers and breeders. The green leafy vegetables of the Brassicaceae family have especially gained attention due to their many health benefits. However, little information is available about abiotic stress’s effects on Brassica vegetables’ growth and development. An experiment was conducted on two Brassica species: B. oleracea L. var. acephala WINTERBOR F1 (hybrid kale) and B. juncea var. GREEN WAVE OG (mustard greens). Seven treatments were imposed on the two brassica species in soil–plant–atmosphere–research (SPAR) units under optimum moisture and nutrient conditions, including a control treatment (optimal temperature and UV-B conditions at ambient CO2 levels), and six treatments where stresses were elevated: CO2, UV-B, temperature (T), CO2+UV-B, CO2+T, and CO2+UV-B+T. Above- and below-ground growth parameters were assessed at 26 d after sowing. Several shoot and root morphological and developmental traits were evaluated under all the treatments. The measured growth and development traits declined significantly under individual stresses and under the interaction of these stresses in both the species, except under elevated CO2 treatment. All the traits showed maximum reductions under high IV-B levels in both species. Leaf area showed 78% and 72% reductions, and stem dry weight decreased by 73% and 81% in kale and mustard, respectively, under high UV-B levels. The increased CO2 concentrations alleviated some deleterious impacts of high temperature and UV-B stresses. The results of our current study will improve our understanding of the adverse effects of environmental stresses on the early-season growth and development of two Brassica species.

Assessment of graphene oxide toxicity on the growth and nutrient levels of white clover (Trifolium repens L.)

Carbon nanomaterials (CNMs) are novel engineered nanomaterials and have been used widely. Their toxic effects on terrestrial plants in soil matrix require careful investigation. In this study, white clover (Trifolium repens L.) was grown in a potted soil with graphene oxide (GO) at levels of 0.2%, 0.4% and 0.6% and the effects of GO on the growth and nutrient uptake of white clover were evaluated after 50 and 100 days of exposure. GO exposure showed adverse effects on seedling growth, photosynthetic parameters and nutrient uptake in shoots, and the effect was more significant with increasing concentration and exposure time. Compared with the control, GO at the highest level of 0.6% decreased plant height, leaf and stem dry weights, total chlorophyll content and net photosynthetic rate by 43.7%, 45.7%, 43.4%, 32% and 85.7%, respectively, after 100 d of exposure, and N, K, Cu, Zn, Fe, Mo, B, Si contents decreased by 19.5%, 20.1%, 12.6%, 25.0%, 12.9%, 26.0%, 18.9%, 23.0%, respectively. Furthermore, the electrolyte leakage, lipid peroxidation, reactive oxygen species, antioxidant enzyme activities were all increased by GO, especially at high dose and long exposure. These results indicate that GO can suppress plant growth by oxidative stress, photosynthesis inhibition, and nutrient imbalance.

Frequency distribution and genetic variability parameters assessment for forage yield attributing traits in oats (Avena sativa L.)

An experiment was conducted with 125 germplasm accessions and five check varieties of Oat (Avena sativa L.) in augmented design during rabi, 2019-20. Nineteen quantitative traits were studied for the assessment of genetic variability. Sufficient variation was exhibited by most of the traits studied. The highest values for GCV and PCV was observed for leaf:stem ratio and seed yield per plant. High heritability and high genetic advance as per cent of mean were observed for 1000 seed weight and leaf:stem ratio. High heritability combined with high genetic advance is the indication of additive gene action and selection based on this would be more effective. The skewness value for most of the traits studied in Oats ranged from -0.5 to 0.5 which indicate that these traits are normally distributed except for days to 50% flowering, flag leaf length, the number of tillers per plant, leaf dry weight per plant and leaf: stem ratio. Plant height, flag leaf width, culm diameter, dry matter yield per plant, stem dry weight per plant and seed yield per plant exhibited negative kurtosis (platykurtic). Keywords: Variability, Skewness, Kurtosis, Forage yield and Oat

Effect of salinity on morpho-physiological traits at reproductive stages of Oryza sativa

Soil salinity is one of the most adverse environmental problems which restricts crop yield. Salinity affects rice plants very badly from germination to its maturity. Therefore, a pot experiment was conducted to study the salinity tolerance of rice genotypes viz. SAL655, STL15, PBRC37, Binadhan-8 and BRRI dhan28. The plants were grown under four salinity levels (0, 6, 9 and 12 dSm−1). Plant height, total number of green leaves hill−1, root dry weight, stem dry weight, total dry weight per hill, root shoot ratio was found to be decreased gradually with gradual increase in salinity levels as compared to the control. The genotype Binadhan-8 and PBRC37 showed the better performance in respect of all the parameters than other genotypes. Therefore, Binadhan-8 and PBRC37 were found more tolerant than other genotypes to salt stress.&#x0D; Progressive Agriculture 32 (2): 117-126, 2021

Assessment of plant growth promotion properties and impact of Microbacterium foliorum for arsenic removal in Melastoma malabathricum

The Microbacterium foliorum species is known for its ability to produce siderophores which, in synergy with the plant root, can effectively affect the rates of arsenate-to-arsenite mobilization, arsenic uptake, and translocation. This study investigates M. foliorum, a plant growth-promoting bacterium (PGPB), in the absorption of arsenic (As) by Melastoma malabathricum plant from contaminated soil. The current study demonstrates M. foliorum phytoremediation’s efficacy in terms of As tolerance, removal, and toxicity in the M. malabathricum plant. For an observation period of 90 days, growing plants were treated with M. foliorum in arsenic-contaminated soil. The morphological trait, pH of soil, and potential advantage induced by M. foliorum on M. malabathricum were evaluated. Plants did not display any noticeable signs of toxicity, however, the root and stem length were significantly increased in the presence of M. foliorum. The Bioconcentration Factor (BCF) was increased in plants inoculated with M. foliorum by 0.3 times, the Transfer Factor (TF) of As in the M. malabathricum plants decreased, whether in the presence or absence of PGPB. The As phytoremediation treatment with M. foliorum also enhanced uptake of As in root (by 26%) and shoot (by 22%) than in the other two (A2 and control) phytoremediation treatments. This shows that M. foliorum inoculation reduced As toxicity through substantial reduction of the adverse stress effects, increased stem and root fresh and dry weight.

Effect of Silver Nanoparticles Treatments on Some Characteristics of “Santander” Lily Cultivar

The use of silver nanoparticles (AgNPs) in the fields of agriculture and horticulture has been increasing recently due to contribution to seed germination, plant growth and development, flowering, yield, and physiological improvements. This research aimed to investigate the effects of silver nanoparticles on the growth and flowering characteristics of the 'Santander' lily (Lilium L.) variety and to determine its potential for use in cultivation. Before planting the plant bulbs immersed in AgNPs solutions of 0 (control), 50, 75, 100, 125 and 150 ppm. After harvest; weight, circumference, height, root length, fresh and dry weight, stem root length, fresh and dry weight of stem, plant height, plant stem diameter, fresh plant weight, bud number and vase life were determined. As a result; it has been indicated that AgNPs solutions in different concentrations increased the quality and quantity of cut flowers and bulbs in lily plants. AgNPs increased an average of 26.29% when compared with control in all morphological characteristics except for the vase life. In the light of these findings, AgNPs applications can be preferred as a method that can be used on lily cultivation and reproduction. Nevertheless, considering the deficiency of treatments of AgNPs in lily plants and their poorly known effect on plants, further detailed studies are necessary.

Agronomic traits, secondary metabolites and element concentrations of Lavandula angustifolia leaves as a response to single or reiterated drought stress: How effective is the previously experienced stress?

Abstract In nature, plants are constantly challenged by an array of drought episodes, which critically affect the distribution of the plants. The drought episodes might occur recurrently, so the plants endure drought by adjusting and shifting their metabolisms. The impacts of subjecting plants to drought stress have been widely investigated, but reports on how reiterated drought stress affects the plants are limited. The present study was designed to investigate the response of lavender, a reputed medicinal and aromatic plant, against single drought, recovery and reiterated drought stress at greenhouse conditions. In this regard, the experimental design was based on three cycles of 11 days of drought by withholding water, followed by subsequent periods of 6 days of recovery, and then double-stressed and single-stressed periods. As expected, the present findings revealed that single stress decreased the fresh and dry weights of the leaf, stem and root. Reiterated drought stress caused critical reductions in the fresh weight of the leaf, stem and root, while the dry weight of stem and root were not significantly affected. Of the estimated traits, only the dry weight of leaf increased with reiterated drought stress. The mineral status of the leaves was adversely affected with single stress, but the effects of recovery and reiterated stress were not in accordance with the improvement in water contents of the leaf and soil. Regarding essential oil compounds, eucalyptol, camphor and endo-borneol were predominant. Single and reiterated drought stress increased camphor percentage, while recovery and full irrigation decreased the percentage. Endo-borneol was decreased under single stress, but reiterated stress increased the percentage of the compound. Considering the phenolic acids, stressed and non-stressed groups were well discriminated and hence, phenolic acids might be useful as good indicators of the stress response in lavender.

RESPUESTA DE Origanum vulgare L. AL ESTRÉS POR NaCl

&lt;p&gt;&lt;strong&gt;Background&lt;/strong&gt;. One of the classic land degradation problems that man has had to face is controlling, preventing, or improving soils affected by salinity. &lt;strong&gt;Objective&lt;/strong&gt;. The objective of this study was to evaluate the physiological and morphometric response of &lt;em&gt;Origanum vulgare&lt;/em&gt; L. plants subjected to five concentrations of NaCl (0, 50, 100, 150 and 200 mM NaCl). &lt;strong&gt;Methodology&lt;/strong&gt;. The experiment was established in a completely randomized design with five treatments based on different concentrations of NaCl (0, 50, 100, 150 and 200 mM) with four replications per treatment. Each repetition consisted of 14 plants. The variables evaluated were fresh and dry weight of leaves, leaf area, fresh and dry weight of stem, stem length, fresh and dry weight, and root length, chlorophyll content a and b, relative water content and water potential. &lt;strong&gt;Results. &lt;/strong&gt;The results showed that the fresh and dry weight of leaves, stem and root, foliar area, as well as the length of stem and root showed significant differences between treatments, they decreased as NaCl concentrations increased in the culture medium, as did the chlorophyll content "a and b". It is concluded that oregano plants have the capacity to absorb Na from the culture medium in 50, 100 and 150 mM of NaCl. &lt;strong&gt;Implications.&lt;/strong&gt; The study makes the possibility to determine the tolerance of oregano to salinity, by subjecting the plants to different concentrations of NaCl and assessing whether it has the capacity to absorb Na&lt;sup&gt;+&lt;/sup&gt; from the culture medium. The study shows that it is possible to grow oregano in floating root hydroponic conditions, considering the advantages that this system offers, such as saving water and nutrients, being possible to obtain adequate yield using water of moderate salinity (50 mM NaCl) that represents an electrical conductivity of 5.8 dS m&lt;sup&gt;-1&lt;/sup&gt;. &lt;strong&gt;Conclusions.&lt;/strong&gt; All variables decreased as NaCl concentrations increased in the culture medium. Oregano showed the ability to absorb Na&lt;sup&gt;+&lt;/sup&gt; from the culture medium in 50, 100 and 150 mM NaCl.&lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;