scholarly journals Photochemical efficiency in pineapple plants under saline water irrigation

Author(s):  
Cleiton Fernando Barbosa Brito ◽  
Varley Andrade Fonseca ◽  
Marcelo Rocha dos Santos ◽  
Sérgio Luiz Rodrigues Donato ◽  
Alessandro De Magalhães Arantes ◽  
...  

Studies determining physiological characteristics of field-grown pineapples irrigated with low-quality water are lacking. This work evaluated the photochemical efficiency of ‘Pérola’ pineapple irrigated with saline water in the semiarid region of Bahia, Brazil. The experiment was carried out in randomized blocks with five treatments consisting of the following irrigation depths: 100% of ETc using water with electrical conductivity (ECw) of 0.75 dS m-1; and 50, 75, 100 and 125% of ETc using water with ECw of 3.6 dS m-1. Chlorophyll a fluorescence measurements were made over the course of 13 months using a pulse-modulated fluorometer, in all treatments. Quantum efficiency (Fv/Fm) fluctuated throughout the cycle of the pineapple with values below the ideal, especially at the end of the crop cycle. Quantum yield of photosystem II (Yield), photochemical quenching (qP), non-photochemical quenching (NPQ) and chlorophyll fluorescence decrease ratio (RFd) were not influenced by irrigation depths. Therefore, energy used for photosynthetic processes in pineapple plants is not affected by irrigation using saline water with electrical conductivity of 3.6 dS m-1.

2015 ◽  
Vol 45 (5) ◽  
pp. 814-820 ◽  
Author(s):  
Antônia Leila Rocha Neves ◽  
Claudivan Feitosa de Lacerda1 ◽  
Carlos Henrique Carvalho de Sousa1 ◽  
Francisco Leandro Barbosa da Silva1 ◽  
Hans Raj Gheyi2 ◽  
...  

This study aimed to evaluate the effect of management strategies of irrigation with saline water on growth and yield of cowpea and sunflower in a crop rotation. The experiment was conducted in randomized blocks with thirteen treatments and five replications. The treatments consisted of: T1 (control), T2, T3 and T4 using water of 0.5 (A1), 2.2 (A2), 3.6 (A3) and 5.0 (A4) dS m-1, respectively, during the entire crop cycle; T5, T6 and T7, use of A2, A3 and A4 water, respectively, only in the flowering and fructification stage of the crop cycle; using different water in a cyclic way, six irrigations with A1 followed by six irrigations with A2 (T8), A3 (T9) and A4, (T10), respectively; T11, T12 and T13, using water A2, A3 and A4, respectively, starting at 11 days after planting (DAP) and continuing until the end of the crop cycle. These treatments were employed in the first crop (cowpea), during the dry season, and the same plots were used for the cultivation of sunflower as succeeding crop during rainy season. The strategies of use of saline water in the salt tolerant growth stage (treatments T5, T6 and T7) or cyclically (treatments T8, T9 and T10) reduced the amount of good quality water used in the production of cowpea by 34 and 47%, respectively, without negative impacts on crop yield, and did not show the residual effects of salinity on sunflower as a succeeding crop. Thus, these strategies appear promising to be employed in areas with water salinity problems in the semiarid region of Brazil.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 541a-541
Author(s):  
Lailiang Cheng ◽  
Leslie H. Fuchigami ◽  
Patrick J. Breen

Bench-grafted Fuji/M26 apple trees were fertigated with different concentrations of nitrogen by using a modified Hoagland solution for 6 weeks, resulting in a range of leaf N from 1.0 to 4.3 g·m–2. Over this range, leaf absorptance increased curvilinearly from 75% to 92.5%. Under high light conditions (1500 (mol·m–2·s–1), the amount of absorbed light in excess of that required to saturate CO2 assimilation decreased with increasing leaf N. Chlorophyll fluorescence measurements revealed that the maximum photosystem II (PSII) efficiency of dark-adapted leaves was relatively constant over the leaf N range except for a slight drop at the lower end. As leaf N increased, non-photochemical quenching under high light declined and there was a corresponding increase in the efficiency with which the absorbed photons were delivered to open PSII centers. Photochemical quenching coefficient decreased significantly at the lower end of the leaf N range. Actual PSII efficiency increased curvilinearly with increasing leaf N, and was highly correlated with light-saturated CO2 assimilation. The fraction of absorbed light potentially used for free radical formation was estimated to be about 10% regardless of the leaf N status. It was concluded that increased thermal dissipation protected leaves from photo-oxidation as leaf N declined.


2019 ◽  
Vol 47 (3) ◽  
Author(s):  
Yaoguo QIN ◽  
Zesheng YAN ◽  
Honghui GU ◽  
Zhengxiang WANG ◽  
Xiong JIANG ◽  
...  

To study the effects of shading level on the photosynthesis and corm weight of konjac plant, the chlorophyll fluorescence parameters, daily variation of relative electron transport rate (rETR), net photosynthetic rate (Pn), and corm weight of konjac plants under different treatments were measured and comparatively analyzed through covered cultivation of biennial seed corms with shade nets at different shading rates (0%, 50%, 70%, and 90%). The results showed that with the increase in shading rate, the maximum photochemical efficiency, potential activity, and non-photochemical quenching of photosystem Ⅱ (PSⅡ) of konjac leaves constantly increased, whereas the actual photosynthetic efficiency, rETR, and photochemical quenching of PSⅡ initially increased and then decreased. This result indicated that moderate shading could enhance the photosynthetic efficiency of konjac leaves. The daily variation of rETR in konjac plants under unshaded treatment showed a bimodal curve, whereas that under shaded treatment displayed a unimodal curve. The rETR of plants with 50% treatment and 70% treatment was gradually higher than that under unshaded treatment around noon. The moderate shading could increase the Pn of konjac leaves. The stomatal conductance and transpiration rate of the leaves under shaded treatment were significantly higher than those of the leaves under unshaded treatment. Shading could promote the growth of plants and increase corm weight. The comprehensive comparison shows that the konjac plants had strong photosynthetic capacity and high yield when the shading rate was 50%-70% for the area.   ********* In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 3, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue. *********


2014 ◽  
Vol 151 (4) ◽  
pp. 544-558 ◽  
Author(s):  
Amir Eppel ◽  
Ruth Shaked ◽  
Gil Eshel ◽  
Simon Barak ◽  
Shimon Rachmilevitch

Author(s):  
Márcia Cristina de Araújo Pereira ◽  
Carlos Alberto Vieira de Azevedo ◽  
José Dantas Neto ◽  
Mariana de Oliveira Pereira ◽  
Jailton Garcia Ramos ◽  
...  

Brazilian semiarid region is characterized by irregular rainy periods that limits the production of forage feed for the maintenance of agricultural livestock and causes losses in the production. Despite that, semiarid region stands out in the production of forage palm, buffering the impact of drought in the area. Thus, this study aimed at analyzing the effect of different levels of salinity in irrigation water on the production of forage palm in the semiarid region. The experiment was arranged as a complete randomized block, in a 4x3 factorial arrangement and four levels of salinity (0.2, 2.0, 3.8 and 5.6 dS m-1); three cultivars (Miúda, Orelha de Elefante Mexicana and IPA-Sertânia) with 4 replications. The variables evaluated were the following: number of primary, secondary, tertiary and total cladodes, cladode biomass and estimative of threshold salinity (SL). The results showed that irrigation with saline water with an electrical conductivity of 2.0 dS m-1 negatively affected the emission of cladodes of superior orders for all forage palm cultivars. Miúda cultivar presented the best production of fresh phytomass (13.36 kg per plant) under a salinity level of 4.04 dS m-1, followed by Orelha de Elefante Mexicana (12.55 kg per plant) under a salinity level of 2.73 dS m-1 and Baiana (11.56 kg per plant) under a salinity level of 2.17dS m-1.


Author(s):  
André Alisson Rodrigues da Silva ◽  
Márcia Cristina de Araújo Pereira ◽  
Luana Lucas de Sá Almeida Veloso ◽  
Ronaldo do Nascimento ◽  
Elka Costa Santos Nascimento ◽  
...  

Water scarcity and high levels of salinity in irrigation water limit irrigated cotton cultivation in the semiarid region of Northeast Brazil. So, it is necessary to adopt cultivation strategies that make the production system feasible. In this context, the present study aimed to evaluate the biomass and production of cotton cultivars subjected to different levels of saline water irrigation. The experiment was carried out under greenhouse conditions, with treatments distributed in a completely randomized design, in a 5 x 2 factorial arrangement, corresponding to five levels of irrigation water electrical conductivity - ECw (1.5, 3.0, 4.5, 6.0 and 7.5 dS m-1) and two cotton cultivars (BRS 368 RF and BRS Safira), with 4 replicates. Treatment effects were measured by the number of bolls per plant, lint weight, number of seeds per plant, total weight of seeds and dry and fresh biomass of stem, roots and leaves. Irrigation using water with electrical conductivity from 1.5 dS m-1 negatively affects the production of the cotton cultivars BRS SAFIRA and BRS 368 RF, causing reductions in all production variables analyzed. The cultivar BRS Safira has better production performance than BRS 368 RF when exposed to water salinity.


HortScience ◽  
2008 ◽  
Vol 43 (5) ◽  
pp. 1479-1484 ◽  
Author(s):  
Genhua Niu ◽  
Denise S. Rodriguez ◽  
Lissie Aguiniga

Salt-tolerant landscape plants are needed for arid and semiarid regions where the supply of quality water is limited and soil salinization often occurs. This study evaluated growth, chloride (Cl) and sodium (Na) uptake, relative chlorophyll content, and chlorophyll fluorescence of three rose rootstocks [Rosa ×fortuniana Lindl., R. multiflora Thunb., and R. odorata (Andr.) Sweet] irrigated with saline solutions at 1.6 (control), 3.0, 6.0, or 9.0 dS·m−1 electrical conductivity in a greenhouse. After 15 weeks, most plants in 9.0 dS·m−1 treatment died regardless of rootstock. Significant growth reduction was observed in all rootstocks at 6.0 dS·m−1 compared with the control and 3.0 dS·m−1, but the reduction in R. ×fortuniana was smaller than in the other two rootstocks. The visual scores of R. multiflora at 3.0 and 6.0 dS·m−1 were slightly lower than those of the other rootstocks. Rosa odorata had the highest shoot Na concentration followed by R. multiflora; however, R. multiflora had the highest root Na concentration followed by R. odorata. All rootstocks had higher Cl accumulation in all plant parts at elevated salinities, and no substantial differences in Cl concentrations in all plant parts existed among the rootstocks, except for leaf Cl concentration in R. multiflora, which was higher than those in the other two rootstocks. The elevated salinities of irrigation water reduced the relative chlorophyll concentration, measured as leaf SPAD readings, and maximal photochemical efficiency of photosystem II (PSII) and minimal fluorescence (Fo)/maximum fluorescence (Fv/Fm), but the largest reduction in Fv/Fm was only 2.4%. Based on growth and visual quality, R. ×fortuniana was relatively more salt-tolerant than the other two rootstocks and R. odorata was slightly more salt-tolerant than R. multiflora.


2020 ◽  
Vol 11 ◽  
pp. e3233
Author(s):  
Saulo Soares da Silva ◽  
Geovani Soares de Lima ◽  
Vera Lúcia Antunes de Lima ◽  
Hans Raj Gheyi ◽  
Lauriane Almeida dos Anjos Soares ◽  
...  

Salt stress is highlighted as one of the limiting factors for the establishment of agriculture in the semiarid region of Northeastern Brazil. In this context, it is essential to look for new strategies aiming at minimizing the effects of salt stress on the crops. The present work aimed to evaluate the photochemical efficiency, photosynthetic pigments, and growth of the watermelon cv. Sugar Baby under different use strategies with saline waters and nitrogen fertilization. The experiment was conducted in a protected environment at the Center of Technology and Natural Resources of the Federal University of Campina Grande, municipality of Campina Grande, Paraíba. An experimental design in randomized blocks was adopted, arranged in a 6 x 2 factorial scheme, with six management strategies of water salinity and two nitrogen doses (corresponding to 50 and 100% of the recommendation), with five replications. Two salinity levels of the irrigation water were studied, one with low and another with a high level of electrical conductivity of the water (ECw = 0.8 and 3.2 dS m-1). The watermelon cv. Sugar Baby expressed higher sensitivity to salt stress in the flowering phase, with a decrease in the synthesis of chlorophyll b, chlorophyll total, and carotenoids. The 50% dose of N provided an increment in the initial fluorescence, stem diameter, and the number of leaves of the watermelon cv. Sugar Baby. The length of the main branch of the watermelon plants decreased with the salt stress applied in the fructification phase; however, the fertilization with 100% of N stimulated a higher growth when the irrigation with saline waters was performed at the vegetative and flowering phases.


2019 ◽  
pp. 1169-1176 ◽  
Author(s):  
Luiz Guilherme Medeiros Pessoa ◽  
Maria Betânia Galvão dos Santos Freire ◽  
Renato Lemos dos Santos ◽  
Fernando José Freire ◽  
Márcio Fléquisson Alves Miranda ◽  
...  

The use of saline water for crop irrigation is a commonly adopted practice among the farmers in the semiarid regions around the world, but the magnitude of soil salinization resulting from the use of these waters is currently insufficiently understood. This work aims to evaluate the chemical attribute changes of two Fluvisols cultivated with onion and subjected to irrigation with increasing levels of salinity, expressed by electrical conductivity (EC) and sodium adsorption ratio (SAR). Sandy loam and silty clay loam soils were irrigated with three different levels of saline waters with electrical conductivity (EC - 200, 700 and 2,000 μS cm-1) and six levels of sodium adsorption ratio (SAR - 0, 5, 10, 15, 20 and 25 (mmolc L-1)0.5). Thus, the experiment consisted of a complete factorial arrangement 2 x 3 x 6 (two soils, three EC levels and six SAR levels), in four replicates. The soils were cultivated with onion and pH levels of the soil were measured at 90 days after transplanting, as were the contents of exchangeable and soluble cations. ESP and SAR values were then calculated. This study revealed that the use of water with salinity at or above 700 μS cm-1 is capable of promoting changes in the chemical properties of soils and the continuous use of irrigation water with high EC and high SAR values may promote salinization and sodification of Fluvisols in a semiarid environment. These changes were found to be more severe in silty clay loam soils than in sandy loam soils.


2011 ◽  
Vol 38 (12) ◽  
pp. 993 ◽  
Author(s):  
P. V. Vara Prasad ◽  
Maduraimuthu Djanaguiraman

High temperature stress is an important abiotic stress limiting sorghum (Sorghum bicolor (L.) Moench) yield in arid and semiarid regions. Climate models project greater increases in the magnitude of night temperature compared with day temperature. We hypothesise that high night temperature (HNT) during flowering will cause oxidative damage in leaves and pollen grains, leading to decreased photosynthesis and seed-set, respectively. The objectives of this research were to determine effects of HNT on (1) photochemical efficiency and photosynthesis of leaves, and (2) pollen functions and seed-set. Sorghum plants (hybrid DK-28E) were exposed to optimum night temperature (ONT; 32 : 22°C, day maximum :  night minimum) or HNT (32 : 28°C, day maximum : night minimum) for 10 days after complete panicle emergence. Exposure to HNT increased thylakoid membrane damage and non-photochemical quenching. However, HNT decreased chlorophyll content, quantum yield of PSII, photochemical quenching, electron transport rate and photosynthesis of leaves as compared with ONT. Exposure to HNT increased the reactive oxygen species (ROS) level of leaves and pollen grains. Lipid molecular species analyses in pollen grains showed that HNT decreased phospholipid saturation levels and altered various phospholipid levels compared with ONT. These changes in phospholipids and greater ROS in pollen grains may be responsible for decreased pollen function, leading to lower seed-set.


Sign in / Sign up

Export Citation Format

Share Document