scholarly journals Effect of Phytohormones, Phosphorus and Potassium on Cotton Varieties (Gossypium hirsutum) Root Growth and Root Activity Grown in Hydroponic Nutrient Solution

2011 ◽  
Vol 4 (3) ◽  
Author(s):  
Adebusoye Olulayo Onanuga ◽  
Ping’an Jiang ◽  
Sina Adl
Agronomy ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 97
Author(s):  
Mazhar H. Tunio ◽  
Jianmin Gao ◽  
Imran A. Lakhiar ◽  
Kashif A. Solangi ◽  
Waqar A. Qureshi ◽  
...  

The atomized nutrient solution droplet sizes and spraying intervals can impact the chemical properties of the nutrient solution, biomass yield, root-to-shoot ratio and nutrient uptake of aeroponically cultivated plants. In this study, four different nozzles having droplet sizes N1 = 11.24, N2 = 26.35, N3 = 17.38 and N4 = 4.89 µm were selected and misted at three nutrient solution spraying intervals of 30, 45 and 60 min, with a 5 min spraying time. The measured parameters were power of hydrogen (pH) and electrical conductivity (EC) values of the nutrient solution, shoot and root growth, ratio of roots to shoots (fresh and dry), biomass yield and nutrient uptake. The results indicated that the N1 presented significantly lower changes in chemical properties than those of N2, N3 and N4, resulting in stable lateral root growth and increased biomass yield. Also, the root-to-shoot ratio significantly increased with increasing spraying interval using N1 and N4 nozzles. The N1 nozzle also revealed a significant effect on the phosphorous, potassium and magnesium uptake by the plants misted at proposed nutrient solution spraying intervals. However, the ultrasonic nozzle showed a nonsignificant effect on all measured parameters with respect to spraying intervals. In the last, this research experiment validates the applicability of air-assisted nozzle (N1) misting at a 30-min spraying interval and 5 min of spraying time for the cultivation of butter-head lettuce in aeroponic systems.


2016 ◽  
Vol 29 (3) ◽  
pp. 656-664 ◽  
Author(s):  
HAMMADY RAMALHO E SOARES ◽  
ÊNIO FARIAS DE FRANÇA E SILVA ◽  
GERÔNIMO FERREIRA DA SILVA ◽  
RAQUELE MENDES DE LIRA ◽  
RAPHAELA REVORÊDO BEZERRA

ABSTRACT Water availability in the Brazilian semiarid is restricted and often the only water source available has high salt concentrations. Hydroponics allows using these waters for production of various crops, including vegetables, however, the water salinity can cause nutritional disorders. Thus, two experiments were conducted in a greenhouse at the Department of Agricultural Engineering of the Federal Rural University of Pernambuco, to evaluate the effects of salinity on the mineral nutrition of crisphead lettuce, cultivar Taina, in a hydroponic system (Nutrient Film Technique), using brackish water in the nutrient solution, which was prepared by adding NaCl to the local water (0.2 dS m-1). A randomized blocks experimental design was used in both experiments. The treatments consisted of water of different salinity levels (0.2, 1.2, 2.2, 3.2, 4.2 and 5.2 dS m-1) with four replications, totaling 24 plots for each experiment. The water added to compensate for the water - depth loss due to evapotranspiration (WCET) was the brackish water of each treatment in Experiment I and the local water without modifications in Experiment II. The increase in the salinity of the water used for the nutrient solution preparation reduced the foliar phosphorus and potassium contents and increased the chloride and sodium contents, regardless of the WCET. Foliar nitrogen, calcium, magnesium and sulfur contents were not affected by increasing the water salinity used for the nutrient solution preparation.


2004 ◽  
Vol 61 (3) ◽  
pp. 313-318 ◽  
Author(s):  
Carlos Eduardo de Oliveira Camargo ◽  
Antonio Wilson Penteado Ferreira Filho ◽  
Marcus Vinicius Salomon

Primary root growth is very important for wheat (Triticum aestivum L.) crop in upland conditions in the State of São Paulo. Fourteen wheat genotypes (mutant lines and cultivars) were evaluated for primary root growth during 7 and 15 days of development in complete and aerated nutrient solutions, in the laboratory. In the first experiment, solutions with three pH values (4.0, 5.0 and 6.0) at constant temperature (24 ± 1°C), and in the second experiment, solutions with the same pH (4.0) but with three temperatures (18°C ± 1°C, 24°C ± 1°C and 30°C ± 1°C) were used. High genetic variability was observed among the evaluated genotypes in relation to primary root growth in the first stages of development in nutrient solutions independent of pH, temperature and growth period. Genotypes 6 (BH-1146) and 13 (IAC-17), tolerant to Al3+ showed genetic potential for root growth in the first stages of development (7 and 15 days), regardless of nutrient solution temperature and pH. Genotypes 14 (IAC-24 M), 15 (IAC-24), 17 (MON"S" / ALD "S") ´ IAC-24 M2, 18 (MON"S" / ALD "S") ´ IAC-24 M3 and 24 (KAUZ"S" / IAC-24 M3), tolerant to Al3+, showed reduced root growth under the same conditions.


1973 ◽  
Vol 38 (1) ◽  
pp. 49-69 ◽  
Author(s):  
E. I. Newman ◽  
Rosalie E. Andrews

1975 ◽  
Vol 2 (2) ◽  
pp. 197 ◽  
Author(s):  
BF Wilson ◽  
EP Bachelard

Fast-growing seedlings of E. regnans F.Muell. survive when bark-girdled, but die when defoliated or detopped or when the stem at a bark girdle is steam-killed. These differences are due to photosynthate passing bark birdles in large quantities, probably in internal primary phloem. Following defoliation or detopping, root elongation stops within 4 days, the root sap turns brown within 8-13 days, and the plant dies in 12-30 days. Total sugars and amino acids in the root sap changed only slightly following girdling or up to 8 days after detopping, but both increased tenfold 8-13 days after detopping. This increase is accompanied by qualitative changes in both sugars and amino acids, and by the appearance of inhibitor(s). Gibberellin and cytokinin activities in the sap are not affected by girdling or detopping. In contrast, fast-growing seedlings of E. viminalis Labill. survive detopping and, although root growth stops by 4 days, root sap stays colourless and without inhibitors.


2019 ◽  
Vol 65 (3) ◽  
pp. 214-223 ◽  
Author(s):  
Juan Li ◽  
Bufan Zheng ◽  
Ruiwen Hu ◽  
Yongjun Liu ◽  
Yongfeng Jing ◽  
...  

Endophytic bacteria are generally helpful for plant growth and protection. We isolated from tobacco seeds three Pseudomonas strains (K03, Y04, and N05) that could produce siderophores, indole-3-acetic acid, and 1-aminocyclopropane-1-carboxylate deaminase, fix nitrogen, dissolve phosphorus and potassium, and tolerate heavy metals. In pot experiments, the three isolated strains significantly promoted root growth and increased the root enzyme activity in Nicotiana tobacum K326. Furthermore, bacterial inoculations increased the proportion of residual lead (Pb) by 8.36%–51.63% and decreased the total Pb content by 3.28%–6.38% in the contaminated soil during tobacco planting, compared with uninoculated soils. An effective decrease in Pb content was also found in tobacco leaves with bacterial inoculations. K03 inoculation decreased the Pb content in the upper leaves by 49.80%, and Y04 inoculation had the best effect, decreasing the Pb content in the middle leaves by 70.12%. Additionally, soil pH and root activity had significant effects on transformation and translocation of Pb. The study suggested that in response to Pb pollution in soil, a reasonable application of endophytes (e.g., Pseudomonas) might be a promising approach in promoting tobacco growth and reducing Pb content in tobacco, while simultaneously enhancing Pb stabilization in soils.


1997 ◽  
Vol 20 (6) ◽  
pp. 613-623 ◽  
Author(s):  
Donald T. Krizek ◽  
George F. Kramer ◽  
Roman M. Mirecki

1969 ◽  
Vol 96 (2) ◽  
pp. 149 ◽  
Author(s):  
Gerard S. Weissman ◽  
Alfred J. Keys

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