•Selenium (Se) application improved growth and yield of drought-stressed tomato plants.•Oxidative stress biomarkers were suppressed with improving the antioxidant system by Se under drought ...stress.•Se application maintained membrane integrity and cell water status in drought-stressed plants.•Se application maintained photosynthetic efficiency in drought-stressed plants.•Se application through soil addition was more effective than Se application through foliar spraying.
Selenium (Se) has been reported to mitigate abiotic stress effects on various plant species, including drought. This study aimed at exploring the potential impacts of Se applied at three levels (0, 20, and 40 mM) in two methods (soil addition or foliar spraying) on growth, yield and its quality, physio-biochemical attributes, and components of the antioxidant defense system in tomato plant growing under irrigation water deficit (from 100 % to 60 % of soil field capacity; SFC) during the 2017 and 2018 seasons. For the application of Se to soil, the concentration of Se in the tested soil was also evaluated at the end of the experiments, and the results obtained showed that Se concentration in the soil was significantly increased. Reducing irrigation water from 100 % to 60 % of SFC led to a marked increase in electrolyte leakage (EL) and oxidative stress biomarkers (malondialdehyde; MDA, hydrogen peroxide; H2O2, and superoxide; O2•−), which associated with increased contents and activities of osmoprotectants and components (enzymatic and non-enzymatic) of the antioxidant defense system. In contrast, growth traits, relative water content (RWC), membrane stability index (MSI), photosynthetic efficiency, Se content, and yield and its fruit Se content were decreased in both seasons. Both 20 and 40 mM Se significantly increased contents and activities of osmoprotectants and components of the antioxidant defense system, which were reflected in reduced EL and oxidative stress biomarkers and increased growth traits, RWC, MSI, photosynthetic efficiency, Se content, and yield and its quality. Compared to foliar spray, better results were obtained with Se application to the soil. The interaction among the three factors; water deficit, Se level, and Se application method was significant. The combination of irrigation at 60 % of SFC × Se application at 40 mM × Se application to soil was preferable, which can be recommended for use to maximize tomato productivity and quality in the dry environment.
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•Agro-industrial treated wastewater was reused for tomato and broccoli irrigation.•The main physico-chemical properties of wastewater met the Italian standards for irrigation ...reuse.•Quantity and quality of crops were not affected by wastewater.•No impact of wastewater on chemical properties of irrigated soil was observed.•Low level of fecal indicator was found in plants, tomato fruits and broccoli heads.
In many countries of the Mediterranean region, characterized by frequent drought periods, agricultural production often occurs under water deficiency or conditions that cause the depletion of the existing water resources. In these areas, the reuse of reclaimed wastewater for crop irrigation could contribute to mitigate/decrease water shortage, support the agriculture sector and protect groundwater resources. In 1.5-year field experiments in Southern Italy (Apulia Region), the effects of irrigation with treated agro-industrial wastewater on soil properties, crops yield and qualitative traits of crop products, including their microbiological safety, were assessed. Groundwater (GW), secondary treated wastewater (SW) and tertiary treated wastewater (TW) from an innovative “on-demand” UV disinfection system were used to irrigate tomato and broccoli, cultivated in succession. The three irrigation water sources and the corresponding irrigated soils, plants and crop products were analyzed for the main physico-chemical characteristics, quali-quantitative parameters and fecal indicators. SW and TW showed higher values of the main physico-chemical parameters than GW. SW irrigated soil resulted in a significant increase of NH4-N, Na+, SAR, EC (below the threshold value beyond which a soil is defined as saline) during the first tomato crop cycle, and of pH during the broccoli growing season. Irrigation with treated wastewater did not significantly affect the marketable yield nor the qualitative traits of tomato and broccoli crops, except for the Na+ and NO3− content (below the threshold levels defined by the European guidelines for vegetables). High levels of E. coli (above the Italian limit for reuse), Fecal coliforms and Fecal enterococci (up to 104 CFU 100ml−1) were observed in the SW and, when chlorination was not done, in the TW. Nevertheless, E. coli was not isolated from any sample of soil, plant and crop product, probably due to its rapid die-off. Moreover, low concentrations of Fecal coliforms and Total heterotrophic count were found in plant and crop product. The drip irrigation system used, which avoided the close contact between water and plant, may have contributed to this. Under the conditions applied in this study, the reuse of treated agro-industrial wastewater for irrigation can be considered an effective way to cope with agricultural water shortage in the Mediterranean area.
•Nano-K maximized salt-stressed squash plant productivity and yield quality.•Nano-K catalyzed more antioxidant activities, attenuating damage of oxidative stress markers.•Nano-K efficiently improved ...photosynthesis and plant integrity under salt stress.•Nano-K efficiently restored the nutrients of salt-stressed squash plants.•Nano-K efficiently improved antioxidant enzymes and their gene expression in salt-stressed squash plants.
To explore the reinforcing effects of nano-potassium fertilizer (nano-K) on growth, yield and quality, physio-biochemical responses, antioxidant defense systems, antioxidant gene expressions, and nutrients of salt-stressed squash plants, field experiments were performed using normal (EC = 2.34 dS m−1) and saline (EC = 9.38 dS m−1) soils during the 2021 and 2022 seasons. The traditional recommended K at full dose (TRK100) or half dose (TRK50) was used in both soils. Salinity and/or TRK50 significantly decreased photosynthetic pigment contents (by 8.7−22.5%), photosynthetic efficiency (by 6.0−10.9%), relative water content (RWC by 5.0−5.1%), membrane stability index (MSI by 7.2−7.4%), nutrient contents (by 28.4−48.2%), K+/Na+ ratio (by 66.4−67.1%), which contributed to the decrease in growth (by 12.2−25.8%) and yield traits (by 4.2−28.5%), and fruit quality (by 8.5−19.7%) due to an increment of oxidative stress biomarker (O2•‒ by 32.4−52.9% and H2O2 30.4−57.1%) levels, electrolyte leakage (EL by 23.3−24.5%), malondialdehyde (MDA by 71.4−77.6%), and Na+ (by 55.5−56.9%). Under stress in both soils, foliar-applied 0.50 g nano-K L−1 suppressed the levels of O2•‒, H2O2, MDA, EL, and Na+, while noticeably increased photosynthetic pigment contents, photosynthetic efficiency, RWC, MSI, nutrient contents, K+/Na+ ratio, which were positively reflected in growth and yield traits, and fruit quality due to increased osmoprotectant and low-molecular-weight antioxidant contents, antioxidant enzyme activities and enzymatic gene expressions. Therefore, our findings recommend using nano-K as an effective strategy to promote antioxidant and photosynthetic machineries, minimize oxidative stress biomarkers and Na+ levels, boost tolerance to salt stress, and improve squash yield and yield quality under salt stress.
Shows the reinforcing effect of nano-K on the antioxidant defense system reflecting the increased yield and quality of salt-stressed squash plants Display omitted
An early maize (Zea mays L.) sowing date plays a key role in increasing the grain yield, especially in a temperate climate. The adoption of reduced tillage techniques, such as strip tillage (ST), can ...decrease cultivation costs, compared to plowing (PLOW), but might also reduce the crop early development rate as a result of lower soil temperatures. Therefore, farmers often adopt starter fertilizations when sowing maize, in order to improve the early-season nutrient uptake, nutrient use efficiency and plant development. The aims of this study were to assess the effects of the adoption of ST, compared to PLOW, and a starter fertilization with deep-injected digestate (DIG) or sub-surface placed diammonium phosphate (DAP), compared to an unfertilized treatment (NT) on the early growth, grain yield and grain qualitative and sanitary traits of maize. Field experiments were carried out in NW Italy over the 2019 and 2020 growing seasons on two different soils. ST determined cooler soil conditions at both sites, compared to PLOW, thus resulting in lower NDVI values due to both slower plant development and lower final crop density. The starter fertilization with DAP recorded the best early vigor and canopy development, expressed as plant height in both sites and for both tillage techniques, while the DIG values were intermediate between the DAP and NT treatments. Although the effects on the early vigor of maize differed between the experimental sites, displaying more pronounced differences in the finer-textured soil, ST on average delayed the flowering (+2.2 days) and consequently delayed the moisture dry down process (+1.2% grain moisture content at harvest), compared to PLOW. The starter fertilization with DIG or DAP led to an earlier flowering, compared to NT (−2.6 and −4.6 days, respectively). The grain yield was not affected by the tillage system, as the plants in ST compensated for the lower plant density with an increased ear length (+1.5%). Instead, DIG and DAP recorded similar and higher grain yields (+1.8 and +1.6 Mg ha−1) than NT. DIG application led to a higher grain protein content and lower level of fumonisin contamination than the other treatments, while ST determined higher deoxynivalenol values than PLOW. The combination of ST and DIG as a starter fertilization can help maintain the production level and the grain quality, compared to conventional techniques that involve the use of mineral fertilizers and plowing, thereby leading to a higher sustainability of the maize cropping system.
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•No difference in grain yield was observed between strip tillage and plowing.•Strip tillage delayed the early growth of maize, compared to plowing.•In-band injected digestate led to moderate advantages on maize early development.•Both organic and mineral NP starter fertilizations increased the grain yield.•Strip tillage only increased the risk of deoxynivalenol contamination.
The use of light-emitting diode (LED) technology for plant cultivation under controlled environmental conditions can result in significant reductions in energy consumption. However, there is still a ...lack of detailed information on the lighting conditions required for optimal growth of different plant species and the effects of light intensity and spectral composition on plant metabolism and nutritional quality. In the present study, wheat plants were grown under six regimens designed to compare the effects of LED and conventional fluorescent lights on growth and development, leaf photosynthesis, thiol and amino acid metabolism as well as grain yield and flour quality of wheat. Benefits of LED light sources over fluorescent lighting were manifested in both yield and quality of wheat. Elevated light intensities made possible with LEDs increased photosynthetic activity, the number of tillers, biomass and yield. At lower light intensities, blue, green and far-red light operated antagonistically during the stem elongation period. High photosynthetic activity was achieved when at least 50% of red light was applied during cultivation. A high proportion of blue light prolonged the juvenile phase, while the shortest flowering time was achieved when the blue to red ratio was around one. Blue and far-red light affected the glutathione- and proline-dependent redox environment in leaves. LEDs, especially in Blue, Pink and Red Low Light (RedLL) regimens improved flour quality by modifying starch and protein content, dough strength and extensibility as demonstrated by the ratios of high to low molecular weight glutenins, ratios of glutenins to gliadins and gluten spread values. These results clearly show that LEDs are efficient for experimental wheat cultivation, and make it possible to optimize the growth conditions and to manipulate metabolism, yield and quality through modification of light quality and quantity.
•Net photosynthetic rate (A) of lettuce was enhanced to some extent by increasing the dissolved oxygen concentration or temperature.•Increasing the dissolved oxygen concentration or temperature can ...reduce the nitrate content of lettuce to a certain extent and improve the quality of lettuce.•The fresh weight and Dry matter accumulation (Dm) of lettuce increased to a certain extent with increasing dissolved oxygen concentration or temperature.•Increasing the dissolved oxygen concentration or temperature have positive effects on lettuce yield, IWUE, WUE and WUEint.
With the continuous improvement of living standards, people pursue vegetables of higher quality, and increasing the yield and quality of vegetables has become the goal of many researchers. To accurately study the effects of different dissolved oxygen concentrations (6.5, 7.5, and 8.5 mg L−1) in the irrigation water or climatic chamber temperatures (16, 18, and 20 °C) on the growth, photosynthesis, yield and quality of lettuce (Lactuca sativa L. var. Grand Rapids Tbr), a comparative design based on a three-color light climate chamber was used. An increase in the dissolved oxygen concentration and the temperature had significant effects on the plant height, transpiration rate (E), soluble protein and nitrate contents (P < 0.05), net photosynthetic rate (A), stomatal conductance (gsw), intercellular carbon dioxide concentration (Ci), leaf temperature (Tleaf), vitamin C content, yield and irrigation water use efficiency (IWUE) of lettuce (P < 0.01). Compared with a dissolved oxygen concentration of 6.5 mg L−1 (O1), the plant height, leaf area index (LAI), chlorophyll content, A, dry matter accumulation (Dm), vitamin C content, soluble protein content, yield, IWUE and water use efficiency (WUE) of O3 (i.e., higher dissolved oxygen content) increased by 22.86%, 35.69%, 12.09%, 163.95%, 14.70%, 39.90%, 77.21%, 32.79%, 32.79%, and 5.84% (P < 0.05), respectively, while the nitrate content decreased by 14.37% (P < 0.05). Compared with a climate chamber temperature of 16 °C (T1), the plant height, LAI, chlorophyll, A, Dm, vitamin C mass fraction, yield, IWUE and WUE of T3 (i.e., higher temperature) increased by 18.33% (P < 0.05), 24.09% (P> 0.05), 9.79% (P < 0.05), 114.89% (P < 0.05), 14.70% (P < 0.05), 55.05%, 38.05%, 17%, 38.17% and 23.5% (P < 0.05), respectively, and decreased the nitrate and soluble protein contents by 72.73% and 11.66%, respectively (P < 0.05). Increasing the dissolved oxygen concentration in the irrigation water or the climate chamber temperature enhanced the growth, photosynthetic ability, and WUE of lettuce, thus increasing the Dm, yield, and nutritional value and improving the quality and flavor of lettuce. Regarding dissolved oxygen, at an irrigation quota of 48 mm, a fertilization rate of 1.30 g pot−1, and a climate chamber temperature of 18 °C, the lettuce yield and quality were optimal at a dissolved oxygen concentration of 8.5 mg L−1. Regarding temperature, at an irrigation quota of 48 mm, a fertilization rate of 1.30 g pot−1, and a dissolved oxygen concentration of 7.5 mg L−1, the yield and quality of lettuce in the climate chamber were optimal when the climate chamber temperature was 20 °C. These results provide conditions viable for increased yield and quality of lettuce.
A field experiment was conducted for three years (2019-20, 2020-21 and 2021-22) at Main Sugarcane Research Station, Navsari Agricultural University (NAU), Navsari, Gujarat to study the effect of ...planting geometry for single eye budded settling on growth, yield and quality of sugarcane under South Gujarat condition. Five inter row spacing treatments comprising of planting single eye bud settling at 90 cm row spacing (R1), 105 cm (R2), 120 cm (R3), 60-120-60 cm pair row spacing (R4) and 90-120-90 cm pair row spacing (R5) and three intra row spacing viz., 30 cm (I1), 45 cm (I2) and 60 cm (I3) were evaluated in split plot design with three replications. In inter row spacing, planting single eye bud settling at 60-120-60 cm pair row spacing found significantly superior for plant height (214 cm), number of tillers per plant (5.43), number of millable canes (95548), cane yield (199 t/ha) and CCS yield (14.02 t/ha). In intra row spacing, planting of single eye bud settling at 30 cm gave significantly more plant height at 180 DAP (207 cm), number of millable canes (91243) and cane yield (113 t/ha) than rest of treatments. While number of tillers per plant (7.32) was highest under treatment I3 (planting of single eye bud settling at 60 cm). In case of economy, treatment R3 (120 cm inter row spacing) obtained higher net income (Rs. 252989/ha) and B:C ratio (2.56) followed by treatment R4(60-120-60 cm pair row spacing) with net income (Rs. 252892/ha) and B:C ratio (2.38). Among intra row spacing treatments, treatment I2 (45 cm recorded higher net return (Rs. 235008/ha). In case of B:C ratio, I3 (60 cm) recorded highest B:C ratio (2.47) followed by treatments I2(2.39). On the basis of pooled results, it is concluded from the study that higher yield and net returns of sugarcane crop can be achieved with planting single eye bud settling either at 120 cm row spacing or 60-120-60 cm pair row spacing; intra row spacing should be kept 45 cm under south Gujarat condition.
An experiment was conducted during 2021-22 to evaluate the performance of early maturing high yielding sugarcane varieties at ICAR-Sugarcane Breeding Institute, Coimbatore. The experiment was planted ...in split plot design and replicated twice. Seven elite sugarcane genotypes Co 11015, Co 15005, Co 15006, Co 15007, Co 15009, Co 15010, Co 15021 were assessed agronomically with three standards checks i.e. Co 09004, Co 86032 and CoC 671 and two fertilizer levels i.e. 100 and 125 % RDF. The experiment was planted in wide row spacing (150 cm). The crop was harvested at 12th month and observation on NMC, cane height, cane girth, number of nodes, cane weight and cane yield per plot was recorded. Cane yield was influenced significantly due to different elite genotypes wherein, elite sugarcane genotypes, Co 15010 (139.79 t/ha) recorded significantly higher cane yield than the standards Co 86032 (114.85 t/ha), Co09004 (108.74 t/ha) and CoC 671(94.20 t/ha). Juice quality (Brix, sucrose, purity and CCS percent) were studied at harvest with random cane samples. Juice qualities were not influenced significantly due to fertilizer levels; however juice Brix, Sucrose%, Purity % and CCS % at harvest showed significant varietal differences.
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