Residual acidified biochar modulates growth, physiological responses, and water relations of maize (Zea mays) under heavy metal–contaminated irrigation water

Sustainability of rice production under flooding conditions has been challenged by water shortage and food demand. Applying higher nitrogen fertilization could be a practical solution to alleviate the deleterious effects of water stress on lowland rice (Oryza sativa L.) in semi-arid conditions. For this purpose, field experiments were conducted during the summer of 2017 and 2018 seasons. These trials were conducted as split-split based on randomized complete blocks design with soil moisture regimes at three levels (120, 100 and 80% of crop evapotranspiration (ETc), nitrogen fertilizers at two levels (N1—165 and N2—200 kg N ha−1) and three lowland Egyptian rice varieties [V1 (Giza178), V2 (Giza177) and V3 (Sakha104)] using three replications. For all varieties, growth (plant height, tillers No, effective tillers no), water status ((relative water content RWC, and membrane stability index, MSI), physiological responses (chlorophyll fluorescence, Relative chlorophyll content (SPAD), and yield were significantly increased with higher addition of nitrogen fertilizer under all water regimes. Variety V1 produced the highest grain yield compared to other varieties and the increases were 38% and 15% compared with V2 and V3, respectively. Increasing nitrogen up to 200 kg N ha−1 (N2) resulted in an increase in grain and straw yields by 12.7 and 18.2%, respectively, compared with N1. The highest irrigation water productivity (IWP) was recorded under I2 (0.89 kg m−3) compared to (0.83 kg m−3) and (0.82 kg m−3) for I1 and I3, respectively. Therefore, the new applied agro-management practice (deficit irrigation and higher nitrogen fertilizer) effectively saved irrigation water input by 50–60% when compared with the traditional cultivation method (flooding system). Hence, the new proposed innovative method for rice cultivation could be a promising strategy for enhancing the sustainability of rice production under water shortage conditions.

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Surface and Internalized Escherichia coli O157:H7 on Field-Grown Spinach and Lettuce Treated with Spray-Contaminated Irrigation Water

Journal of Food Protection ◽

10.4315/0362-028x-73.6.1023 ◽

2010 ◽

Vol 73 (6) ◽

pp. 1023-1029 ◽

Cited By ~ 122

Author(s):

MARILYN C. ERICKSON ◽

CATHY C. WEBB ◽

JUAN CARLOS DIAZ-PEREZ ◽

SHARAD C. PHATAK ◽

JOHN J. SILVOY ◽

...

Keyword(s):

Escherichia Coli ◽

Irrigation Water ◽

Enrichment Culture ◽

Field Studies ◽

Plate Count ◽

Escherichia Coli O157 ◽

Adaxial Side ◽

Abaxial Side ◽

E Coli ◽

Contaminated Irrigation Water

Numerous field studies have revealed that irrigation water can contaminate the surface of plants; however, the occurrence of pathogen internalization is unclear. This study was conducted to determine the sites of Escherichia coli O157:H7 contamination and its survival when the bacteria were applied through spray irrigation water to either field-grown spinach or lettuce. To differentiate internalized and surface populations, leaves were treated with a surface disinfectant wash before the tissue was ground for analysis of E. coli O157:H7 by direct plate count or enrichment culture. Irrigation water containing E. coli O157:H7 at 102, 104, or 106 CFU/ml was applied to spinach 48 and 69 days after transplantation of seedlings into fields. E. coli O157:H7 was initially detected after application on the surface of plants dosed at 104 CFU/ml (4 of 20 samples) and both on the surface (17 of 20 samples) and internally (5 of 20 samples) of plants dosed at 106 CFU/ml. Seven days postspraying, all spinach leaves tested negative for surface or internal contamination. In a subsequent study, irrigation water containing E. coli O157:H7 at 108 CFU/ml was sprayed onto either the abaxial (lower) or adaxial (upper) side of leaves of field-grown lettuce under sunny or shaded conditions. E. coli O157:H7 was detectable on the leaf surface 27 days postspraying, but survival was higher on leaves sprayed on the abaxial side than on leaves sprayed on the adaxial side. Internalization of E. coli O157:H7 into lettuce leaves also occurred with greater persistence in leaves sprayed on the abaxial side (up to 14 days) than in leaves sprayed on the adaxial side (2 days).

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Physiological Response of Thallasia hemprichii on Antrophogenic Pressure In Pari Island, Seribu Islands, DKI Jakarta

ILMU KELAUTAN Indonesian Journal of Marine Sciences ◽

10.14710/ik.ijms.22.1.40-48 ◽

2017 ◽

Vol 22 (1) ◽

pp. 40 ◽

Cited By ~ 1

Author(s):

Aditya Hikmat Nugraha ◽

Dietriech G. Bengen ◽

Mujizat Kawaroe

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Physiological Responses ◽

Research Station ◽

Marine Biota ◽

Nursery Ground ◽

Thalassia Hemprichii ◽

Growth Physiology ◽

Rhizome Growth ◽

Seagrass Ecosystem

Seagrass ecosystem is one of tropical marine ecosystem and have important function. The function of ecosystem like a feeding and nursery ground for marine biota. Antrophogenic pressure is one of threat for seagrass ecosystem sustainability. This research study about effect antropogenic pressure for seagrass Thallasia hemprichii physiology response in some different location at Great Barrier Pari Island. The physiology response study cover growth, heavy metal bioaccumulation and histology analysis. The result shows that growth of leaf and rhizome Thalassia hemprichii have positif correlation with nutrient consentration in environment. The highest growth of leaf Thalassia hemprichii at 2nd station (4.16 mm.day-1) and the highest growth of rhizome Thalassia hemprichii at 4th station (1.3 mm.day-1). Seagrass can accumulation heavy metal from environment. The highest heavy metal accumulation is Pb. Not correlation between heavy metal consentration in seagrass with heavy metal concentration from environment. Analysis histology result that not damage seagrass tissue in all research station. Keyword : Bioacumulation,Growth,Physiology,Seagrass, Thalassia hemprichiiSeagrass ecosystems is one of the tropical marine ecosystems that have important functions, among others as a feeding and nursery ground for marine life. Anthropogenic stress is one of the threats that may inhibit the survival of seagrass ecosystems. This study examines the effects of anthropogenic pressures on physiological responses of seagrass Thalassia hemprichii at several different locations in Pari Islands. Physiological responses studied were leaves and rhizome growth, bioaccumulation of heavy metals and histological tissue analysis on seagrass. The results showed that the growth response of seagrass has a positive correlation with the nutrients in the environment. Seagrass leaf growth is highest at Station 2 (4.16 mm.day-1) and rhizome growth is highest at Station 4 (1.3 mm.day-1). Seagrass accumulate heavy metals from the environment and accumulation of heavy metals is highest on Pb. There is no correlation between the concentration of heavy metals in the seagrass and environment. The results of histological analysis showed that there was no damage to the tissue of seagrass leaf and rhizome. Keywords : Bio-acumulation, Growth, Physiology, Seagrass, Thalassia hemprichii

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Water Relations and Gas Exchanges of West Indian Cherry under Salt Stress and Nitrogen and Phosphorus Doses

Journal of Agricultural Science ◽

10.5539/jas.v9n10p168 ◽

2017 ◽

Vol 9 (10) ◽

pp. 168 ◽

Cited By ~ 2

Author(s):

Francisco V. da S. Sá ◽

Hans R. Gheyi ◽

Geovani S. de Lima ◽

Emanoela P. de Paiva ◽

Pedro D. Fernandes ◽

...

Keyword(s):

Chlorophyll A ◽

Water Relations ◽

Irrigation Water ◽

Chlorophyll A Fluorescence ◽

Saline Water ◽

Block Design ◽

West Indian ◽

N Fertilization ◽

Nitrogen And Phosphorus ◽

Gas Exchanges

This study aimed to evaluate the interaction between the fertilization with nitrogen (N) and phosphorus (P) and irrigation with saline water on the water relations, gas exchanges and chlorophyll a fluorescence in West Indian cherry in the vegetative stage. The study was carried out in protected environment, using lysimeters filled with clay loam Regolithic Neosol, with low P content, installed in a randomized block design, arranged in a factorial scheme with five levels of electrical conductivity of irrigation water (ECw), and four managements of P and N fertilization, with three replicates and one plant per plot. Along the experiment, water relations, gas exchanges and chlorophyll a fluorescence were evaluated in West Indian cherry plants. The increase in irrigation water salinity reduces the gas exchanges of the plants, but the increment of 40% in N supply increases the photosynthetic activity of West Indian cherry at recommendation levels higher than 100:100% of the P/N ratio, when irrigated with ECw of up to 3.0 dS m-1. The combined action of N and P, at doses of 140:140% N/P recommendation, increases leaf turgor in the plants, regardless of the ECw level. The increment of 40% in N dose reduces the effects of salinity on the initial fluorescence of chlorophyll a in West Indian cherry irrigated with up to 2.2 dS m-1.

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