scholarly journals Increasing the Yield of Lactuca sativa, L. in Glass Greenhouses through Illumination Spectral Filtering and Development of an Optical Thin Film Filter

2020 ◽  
Vol 12 (9) ◽  
pp. 3740 ◽  
Author(s):  
Jacqualine A Thomas ◽  
Mikhail Vasiliev ◽  
Mohammad Nur-E-Alam ◽  
Kamal Alameh
Keyword(s):  
Thin Film ◽  
Lactuca Sativa ◽  
Energy Savings ◽  
Biomass Productivity ◽  
World Population ◽  
Light Illumination ◽  
Climate Control ◽  
Dielectric Thin Film ◽  
Lactuca Sativa L ◽  
Thin Film Filter

With the increase in world population, the continued advances in modern greenhouse agriculture and plant growth practices are expected to help overcome the global problem of future food shortages. The next generation greenhouse design practices will need to address a range of issues, ranging from energy and land use efficiency to providing plant-optimized growth techniques. In this paper, we focus on investigating the optimum irradiation spectra matched to the lettuce species (Lactuca sativa, L.), commonly grown in greenhouse environments, in order to develop low-emissivity glass panes that maximize the biomass productivity of glass greenhouses. This low-emissivity glass passes the solar spectral components needed for crop growth, while rejecting other unwanted radiations. This could potentially lead to significant energy savings and other beneficial effects related to greenhouse climate control, in a range of climates. The experimental results show that substantial biomass productivity improvements in lettuce (up to approximately 14.7%) can be attained by using spectrally optimized illumination, instead of white light illumination. This optimized wavelength is then demonstrated as being used to develop an advanced metal-dielectric thin-film filter that produces the optimized illumination spectrum when exposed to sunlight.

scholarly journals Increasing the Energy Savings and Yield of Lactuca sativa, L. in Glass Greenhouses through Illumination Spectral Filtering

2020 ◽  
Author(s):  
Jacqualine A. Thomas ◽  
Mikhail Vasiliev ◽  
Mohammad Nur-E-Alam ◽  
Kamal Alameh
Keyword(s):  
Lactuca Sativa ◽  
Energy Savings ◽  
Biomass Productivity ◽  
World Population ◽  
Climate Control ◽  
Dielectric Thin Film ◽  
Beneficial Effects ◽  
Greenhouse Climate ◽  
Land Use Efficiency ◽  
Food Shortages

With the dramatic increase in world population, continued advances in modern greenhouse agriculture and plant growth practices are expected to help overcome the global problem of future food shortages. Next generation greenhouse design practices will need to address a range of issues, ranging from energy and land use efficiency to providing plant-optimised growth techniques. In this paper, we focus on investigating the optimum irradiation spectra matched to the lettuce species (Lactuca sativa, L.), which is commonly grown in greenhouse environments, in order to develop low-emissivity glass panes that maximize the biomass productivity of glass greenhouses. This low-emissivity glass passes the solar spectral components needed for crop growth, while rejecting other unwanted radiations, leading to significant energy savings and other beneficial effects related to greenhouse climate control, in a range of climates. This is due to reducing both the solar heat gain and photosaturation, which can raise the temperature of the crops to harmful levels. Experimental results show that substantial biomass productivity improvements in lettuce (up to ~14.7%) can be attained using spectrally optimized illumination, compared with white light irradiation. We also report on the development of advanced metal-dielectric thin-film filters that produce the optimum illumination spectrum when exposed to sunlight.

scholarly journals Changes in the Chemical Composition of Six Lettuce Cultivars (Lactuca sativa L.) in Response to Biofortification with Iodine and Selenium Combined with Salicylic Acid Application

Agronomy ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 660 ◽  
Author(s):  
Sylwester Smoleń ◽  
Iwona Kowalska ◽  
Peter Kováčik ◽  
Włodzimierz Sady ◽  
Marlena Grzanka ◽  
...  
Keyword(s):  
Salicylic Acid ◽  
Chemical Composition ◽  
Lactuca Sativa ◽  
Negative Impact ◽  
Biomass Productivity ◽  
Ascorbic Acid Content ◽  
Greenhouse Study ◽  
Lactuca Sativa L ◽  
Nutrient Film Technique ◽  
Nutrient Solutions

A two-year greenhouse study was conducted to assess the effects of the application of I (as KIO3), Se (as Na2SeO3), and salicylic acid (SA) in nutrient solutions on the chemical composition of six lettuce cultivars, i.e., two butterhead lettuces (BUTL), “Cud Voorburgu” and “Zimująca”; two iceberg lettuces (ICEL), “Maugli” and “Królowa lata”; and two Lactuca sativa L. var. crispa L. (REDL) cultivars, “Lollorossa” and “Redin”, grown in the NFT (nutrient film technique) system. The treatments were as follows: control, I+Se, I+Se+0.1 mg SA dm−3, I+Se+1.0 mg SA dm−3, and I+Se+10.0 mg SA dm−3. KIO3 was used at a dose of 5 mg I dm−3, while Na2SeO3 was used at 0.5 mg Se dm−3. The application of I+Se was a mild abiotic stress factor for the plants of the ICEL and REDL cultivars. In contrast, I+Se did not have a negative impact on the BUTLcultivars. The application of 1.0 mg SA dm−3 improved the biomass productivity in all cultivars compared with I+Se. In the majority of the cultivars, the applied combinations of I+Se and I+Se+SA resulted in a reduction in the nitrate(V) content that was beneficial to the consumer and increased levels of sugars, phenols, phenylpropanoids, flavonols, and anthocyanins. In addition, an increase in ascorbic acid content was observed, but only in the BUTL cultivars and REDL “Redin”. The application of I, Se, and SA had upward or downward effects on the concentrations of N, K, P, Ca, Mg, S, Na, B, Cu, Fe, Mn, Mo, and Zn in the leaves.

Pengaruh Jenis dan Konsentrasi Pupuk Organik Cair terhadap Pertumbuhan dan Produksi Tanaman Selada (Lactuca Sativa l.) secara Hidroponik

2017 ◽  
Vol 2 (01) ◽  
pp. 115-127
Author(s):  
Siti Hilalliyah ◽  
Intan Sari ◽  
Zahlul Ikhsan
Keyword(s):  
Lactuca Sativa ◽  
Lactuca Sativa L

Sistem hidroponik memungkinkan sayuran ditanam di daerah yang kurang subur dan daerah sempit yang padat penduduknya. Alasan penerapan teknik hidroponik yang utama adalah karena terbatasnya lahan pertanian yang produktif untuk memenuhi kebutuhan manusia yang semakin banyak tiap tahunnya, sehingga dibutuhkan suatu terobosan baru untuk memecahkan masalah tersebut. Penelitian ini telah dilaksanakan pada bulan November 2015 sampai bulan Januari 2016 yang bertempat di kampus Fakultas Pertanian Jl. Propinsi Kecamatan Tembilahan Hulu Kabupaten Indragiri Hilir Propinsi Riau.Metode penelitian yang digunakan adalah Rancangan Acak Lengkap (RAL) pola faktorial yang terdiri dari 2 faktor. Faktor pertama adalah jenis POC (N) yang terdiri dari 3 taraf perlakuan yaitu POC Jus Bumi, POC Bonggol Pisang danPOC Limbah Sayuran. Faktor kedua adalah konsentrasi larutan (K) yang terdiri dari 3 taraf perlakuan yaitu 150 ppm, 200 ppm dan 250 ppm. Parameter pengamatan adalah Tinggi Tanaman , Jumlah Daun , Luas Daun , Diameter Batang, Panjang akar ,Volume Akar, Kadar Air, dan Bobot Hasil.Hasil pengamatan menunjukkan bahwa perlakuan jenis POC jus bumi dengan konsentrasi larutan 150 ppm memberikan pertumbuhan dan produksi terbaik untuk tanaman selada secara hidroponik sistem wick. Perlakuan jenis POC limbah sayuran dengan konsentrasi 250 ppm memberikan pertumbuhan dan produksi terbaik selain POC jus bumi sehingga dapat dijadikan sumber POC alternatif.

Effect of Illumination on Organic Polymer Thin-Film Transistors

2003 ◽  
Vol 771 ◽  
Author(s):  
Michael C. Hamilton ◽  
Sandrine Martin ◽  
Jerzy Kanicki
Keyword(s):  
Thin Film ◽  
Thin Film Transistors ◽  
Drain Current ◽  
Charge Carriers ◽  
Electrical Performance ◽  
Organic Polymer ◽  
Light Illumination ◽  
Polymer Thin Film ◽  
Channel Region ◽  
White Light Illumination

AbstractWe have investigated the effects of white-light illumination on the electrical performance of organic polymer thin-film transistors (OP-TFTs). The OFF-state drain current is significantly increased, while the drain current in the strong accumulation regime is relatively unaffected. At the same time, the threshold voltage is decreased and the subthreshold slope is increased, while the field-effect mobility of the charge carriers is not affected. The observed effects are explained in terms of the photogeneration of free charge carriers in the channel region due to the absorbed photons.

KHẢO SÁT DƯ LƯỢNG NITRAT VÀ KIM LOẠI NẶNG (Cu, Pb, Zn) TRONG CÂY RAU XÀ LÁCH (Lactuca sativa L.) TRỒNG Ở PHƯỜNG HƯƠNG LONG - THÀNH PHỐ HUẾ

2015 ◽  
Vol 100 (1) ◽  
Author(s):  
Nguyễn Minh Trí ◽  
Nguyễn Hạnh Trinh ◽  
Nguyễn Thị Hoàng Phương
Keyword(s):  
Lactuca Sativa ◽  
Viet Nam ◽  
Lactuca Sativa L ◽  
Tu 45

Xà lách (Lactuca sativa L.) là một loại rau ăn lá quan trọng có giá trị dinh dưỡng và kinh tế cao. Cây Xà lách có đặc điểm là loại rau ngắn ngày, có thời gian sinh trưởng ngắn khoảng từ 45 - 55 ngày, có thể phát triển tốt trên nhiều loại đất, là loại rau ăn sống được sử dụng rất phổ biến trong bữa ăn hàng ngày của người dân Việt Nam nên nó được trồng quanh năm, do vậy vấn đề về chất lượng lại càng phải được quan tâm nhiều hơn. Bài báo này giới thiệu kết quả phân tích về dư lượng nitrat và các kim loại nặng (Cu, Pb, Zn) trong rau Xà lách vụ Xuân - Hè 2012 - 2013 ở phường Hương Long - thành phố Huế. Kết quả nghiên cứu cho thấy: đất trồng rau Xà lách tại phường Hương Long – thành phố Huế đạt tiêu chuẩn về hàm lượng kim loại nặng (Pb, Zn) theo QCVN 03:2008/BTNMT, nhưng hàm lượng Cu và nitrat là khá cao. Rau Xà lách thành phẩm có dư lượng nitrat cao hơn 1,21% so với quy định và các kim loại nặng (Pb, Zn, Cu) tồn dư trong rau lại ở mức cao và vượt tiêu chuẩn cho phép nhiều lần sẽ ảnh hưởng đến sức khỏe của người sử dụng.

EFEITO DO LIXIVIADO DE VERMICOMPOSTO EM DIFERENTES DILUIÇÕES, COMO BIOFERTILIZANTE PARA A CULTURA DA ALFACE (LACTUCA SATIVA L.)

2018 ◽  
Author(s):  
Ferreira Gabriel Menezes ◽  
Souza Antonio Tassio de Oliveira ◽  
Souza Alisson Silva de ◽  
Gomes Igor Thiago dos Santos ◽  
Cunha Denise de Andrade
Keyword(s):  
Lactuca Sativa ◽  
Lactuca Sativa L

PROMOCIÓN DEL CRECIMIENTO DE PLANTAS DE LECHUGA (Lactuca sativa L.) CON DOSIS SUBLETALES DE OZONO APLICADAS AL MEDIO DE CULTIVO

2015 ◽  
Vol 38 (4) ◽  
pp. 405
Author(s):  
Jorge A. Vázquez-Ybarra ◽  
Cecilia B. Peña-Valdivia ◽  
Carlos Trejo ◽  
Albino Villegas-Bastida ◽  
Sergio Benedicto-Valdéz ◽  
...  
Keyword(s):  
Lactuca Sativa ◽  
Lactuca Sativa L

Las plantas han desarrollado un conjunto de mecanismos morfológicos, bioquímicos y fisiológicos de respuesta a los cambios ambientales de O3. El objetivo de este estudio fue evaluar el efecto de dosis subletales de O3, aplicadas al medio de cultivo, en el crecimiento de plantas de lechuga (Lactuca sativa L.). Con base en el fenómeno denominado hormesis, la hipótesis fue que existe una dosis umbral de O3 que modifica positivamente el metabolismo de las plantas e incrementan su crecimiento y productividad. En un sistema hidropónico de plantas en flotación se evaluaron nueve dosis entre 0.53 y 59.40 mg L-1, aplicadas semanalmente, y se compararon con un testigo sin O3. Las variables del crecimiento que se cuantificaron fueron: diámetro del tallo, altura del tallo, altura de hoja, número total de hojas, longitud de raíz, peso fresco de raíz, biomasa seca de raíz, peso fresco y biomasa del vástago. Las plantas completaron su ciclo de crecimiento sin algún daño en el crecimiento con concentraciones entre 0.53 y 5.94 mg de O3 L-1, pero 20, 40 y 60 mg L-1 fueron letales en plantas de cinco semanas de edad. Estas dosis causaron oscurecimiento y necrosis acelerados de los tejidos foliares y muerte, los cambios de color de las hojas fueron evidentes desde los 20 min posteriores a la única aplicación de O3. Además, las dosis de 2.66 y 3.96 mg L-1 incrementaron significativamente (P ≤ 0.05) el diámetro del tallo, la biomasa fresca en la raíz y el vástago y la biomasa seca en la raíz y el vástago, en promedio 16, 23, 15, 89 y 11 % con respecto al testigo, después de 10 semanas de crecimiento.

Sign in / Sign up

Export Citation Format

Share Document