Greenhouse production of Echinacea purpurea (L.) and E. angustifolia using different growing media, NO3−/NH4+ ratios and watering regimes

2006 ◽  
Vol 86 (3) ◽  
pp. 809-815 ◽  
Author(s):  
Youbin Zheng ◽  
Mike Dixon ◽  
Praveen Saxena

Current field cultivation and wild-harvest methods for the medicinal plant Echinacea are struggling to meet the requirements for a high-quality, uniformly produced crop for human consumption. To help meet this challenge, the potential of using a greenhouse production system for Echinacea production was explored. Echinacea purpurea (L.) Moench and angustifolia DC. var. angustifolia plants were grown in three types of greenhouse production systems: (1) deep flow solution culture (D), (2) pots with either Pro-Mix (P) or (3) sand (S). Plants were irrigated with one of three nutrient solutions containing NO3−/NH4+ ratios of 7:1, 5:1 or 3:1, respectively. The plants grown in the Pro-Mix and the sand systems were either well-watered or subjected to periodical water stress. The results obtained after 12 wk of growth showed that Echinacea root production in the greenhouse systems was comparable with or better than that in the field. Based on root and total biomass production, the Pro-Mix system was the best production system for both E. angustifolia and E. purpurea. In most cases, the NO3−/NH4+ ratio did not have significant effects on the growth of either species. When effects were seen, however, higher NO3−/NH4+ levels generally resulted in greater leaf area, root and total biomass, and a higher root/shoot ratio. Mild periodic water stress did not affect the root/shoot ratio or the root biomass in either species. The application of a periodic water stress reduced leaf area of both species, but a reduction in total biomass was only observed in E. purpurea. Key words: Echinacea, greenhouse production, hydroponic production, medicinal plant, NO3−/NH4+ ratio, water stress

2017 ◽  
Vol 15 (3) ◽  
pp. 450
Author(s):  
RONIEL GERALDO AVILA ◽  
PAULO CESÁR MAGALHÃES ◽  
AMAURI ALVES DE ALVARENGA ◽  
ALYNE DE OLIVEIRA LAVINSKY ◽  
CLEIDE NASCIMENTO CAMPOS ◽  
...  

ABSTRACT – Drought is considered the primary limitation to agriculture and, can reduce grain yield by up to 60%when occurs at pre-flowering in maize. In this context this research, aimed to understand the maize genotypes behaviorto drought management and carbon partitioning between grain production and structures to maintain hydration whensubmitted to drought. Maize genotypes tolerant (DKB390 and P30F35) and sensitive (BRS1010 and 2B710) to droughtwere grown in a greenhouse using two water conditions: irrigated and stressed. Water deficit was imposed atpre-flowering and maintained for twelve days. Leaf water potential, gaseous exchange and male and female floweringinterval were evaluated. At the end of the cycle, production components and root/shoot ratio dry weight were evaluated.Drought-tolerant genotypes used root system as a mechanism of tolerance to drought, which ensure greater efficiencyin absorption and loss of water and, consequently, greater stomatal conductance during the drought, compared to thesensitive-genotypes. In addition, drought-tolerant genotypes showed greater stability in the source-sink relationship,exhibiting higher photosynthetic rate and harvest index.Keywords: water stress, carbon partitioning; root/shoot ratio dry weight, gas exchanges, Zea mays.GENÓTIPOS DE MILHO TOLERANTES À SECA INVESTEM EM SISTEMA RADICULARE MANTEM ALTO ÍNDICE DE COLHEITA DURANTE O ESTRESSE HÍDRICORESUMO- A seca é considerada restrição primária à agricultura, e no milho, quando ocorre no pré-florescimento,pode reduzir o rendimento de grãos em até 60%. Neste contexto, objetivou-se entender como genótipos de milhocontrastantes para tolerância à seca, gerenciam o particionamento de carbono entre produção de grãos e estruturasde manutenção da hidratação durante a seca. Para isso, em casa de vegetação cultivaram-se genótipos de milhotolerantes (DKB390 e P30F35) e sensíveis (BRS1010 e 2B710) à seca, em duas condições hídricas: irrigadonormal e déficit hídrico. No pré-florecimento foi imposto o déficit hídrico, que foi mantido por doze dias.Posteriormente avaliou-se o potencial hídrico foliar, trocas gasosas e intervalo de florescimento masculino e feminino.No final do ciclo, avaliaram-se os componentes de produção e a razão raiz/parte aérea. Constatou-se que, genótipostolerantes utilizaram preferencialmente sistema radicular como um mecanismo de tolerância à seca, o que garantiu aesses genótipos, maior eficiência entre a absorção e perda de água e, consequentemente, maior condutância estomáticadurante a seca, em relação aos genótipos sensíveis. Além disso, os genótipos tolerantes apresentaram maior equilíbrioem suas relações fonte e dreno, exibindo maiores taxa fotossintética e índice de colheita.Palavras-chave: estresse hídrico, particionamento de carbono, razão raiz/parte aérea, trocas gasosas, Zea mays.                                                     


1996 ◽  
Vol 121 (4) ◽  
pp. 699-704 ◽  
Author(s):  
Yaping Si ◽  
Royal D. Heins

Sweet pepper (Capsicum annuum `Resistant Giant no. 4') seedlings were grown for 6 weeks in 128-cell plug trays under 16 day/night temperature (DT/NT) regimes from 14 to 26 °C. Seedling stem length, internode length, stem diameter, leaf area, internode and leaf count, plant volume, shoot dry weight (DW), seedling index, and leaf unfolding rate (LUR) were primarily functions of average daily temperature (ADT); i.e., DT and NT had similar effects on each growth or development parameter. Compared to ADT, the difference (DIF, where DIF = DT - NT) between DT and NT had a smaller but still statistically significant effect on stem and internode length, leaf area, plant volume, stem diameter, and seedling index. DIF had no effect on internode and leaf count, shoot DW, and LUR. The root: shoot ratio and leaf reflectance were affected by DT and DIF. Positive DIF (DT higher than NT) caused darker-green leaf color than negative DIF. The node at which the first flower initiated was related to NT. The number of nodes to the first flower on pepper plugs grown at 26 C NT was 1.2 fewer than those of plants grown at 14 °C NT.


1970 ◽  
Vol 4 (1) ◽  
Author(s):  
EDI PURWANTO

These sets of experiments were conducted at Faculty of Agriculture Sebelas Maret University and the Central Experiment Station of Agricultural Faculty, Sebelas Maret University at Jumantono, Karanganyar, Central Java. The experiments were conducted under greenhouse, laboratory and field condition for each year, while the duration of this research was for two years. The specific objectives of the experiments were: (i) to determine the changes of some morpho-physiological characteristics of water stress soybean and those of unstressed plants at different growth stages; (ii) to evaluate relationship between morpho-physiological traits associated with water stress resistance and yield of soybean. In this study consists some experiments, there are: (i) about response of some soybean cultivars to water stress in screen house and field condition; (ii) about germination response of some soybean cultivars in different concentration 0f PEG; (iii) a bout recovery survival and recovery of soybean seedlings after heat treatment. The plants were well watered before thetreatment. Based on the result of the experiments, the following conclusion could be made: (i) water stress reduced growth, yield and yield components 0 f a II soybean c ultivars used; (li) PEG induced water stress resulted in lower germination, shorter root and shoot length, and increase root-shoot ratio; (iii) the ability of plants to recovery after heat stress have low correlation with drought resistance in this experiment; (iv) the determination of root-shoot ratio in the seedling stage was shown to be suitable screening techniques used to study water stress resistance.© 200'3Jurusan Biologi FMIPA UNS SurakartaKey words: soybean (Glycine max L.), cultivars, water stress.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
A. A. Gaber ◽  
A. F. Abou-Hadid ◽  
Y. A. El- Gabry ◽  
M. H. M. Ebid

In Egyptian sugarcane breeding program, a pot experiment was carried out during 2019 season at Agricultural Research Station, Giza Governorate (latitude 26o 33? N and longitude 31o 12? E), Egypt, to evaluate twenty sugarcane clones, compared with the cultivated variety GT.54-9, under three irrigation water levels IWL (100, 80 and 60% of IWL). The traits FW of the shoot and root, root: shoot ratio, LAI, LAR, Chla, Chlb, Chla: Chlb ratio, carotenoids and proline were assessed. From this study clones 17 had height shoot fresh weight under water stress condition, as same as, clones 1, 18 and 19 had great behavior under water stress. In addition to most of sugarcane tested clones were not affected by increase the degree of water stress from 100 to 80% of IWL. The LAI, Chl.a and Chl.b traits showed the high correlation with shoot fresh weight, whereas, proline had strong relationships with root fresh weight under sugarcane drought stress.


2013 ◽  
Vol 864-867 ◽  
pp. 2478-2484
Author(s):  
Long Hua Ye ◽  
Hai Yong Bao ◽  
Zhi Yun Wang ◽  
Gan Wen Lie ◽  
Hong Yue Chen ◽  
...  

Seedlings ofMichelia macclurei,Cinnamomum camphora,RhodoleiachampioniiandMytilaria laosensiswere placed in open-top chambers (OTC) with three ozonic treatments including E20 (20 ppb), E40 (nature air, 40 ppb) and E160 (160 ppb) and two water treatments. Root biomass, stem biomass and leaf biomass total biomass and root/shoot ratio of four seedling types were evaluated. The results showed that there were no significant differences in impacts of ozone stress and drought stress on root, stem, leaf, and total biomass ofM. macclureiamong different treatments. The biomass ofM. laosensisdecreased with increasing ozone concentration, whereas biomass ofC. camphoraandR. championiichanged irregularly. Most of the biomass of four kind seedlings under ozone and drought intercross stresses was lower than those under ozone stress. The root/shoot ratios of four seedling species were all low. The ratios under high concentration ozone (160 ppb) were lower than the control treatment. And the ratios of different treatments under drought were lower than those were not under drought when they were under the same concentration of ozone.


1989 ◽  
Vol 40 (3) ◽  
pp. 517 ◽  
Author(s):  
GR Baker ◽  
S Fukai ◽  
GL Wilson

Cassava is a potential tuber crop for northern Australia where water stress is likely to occur during some stages of growth. Field and glasshouse experiments were conducted to examine the response of cassava to soil water deficits which developed at various stages. The field experiments, covering 10-month growth durations from planting in spring to harvesting in winter, showed that water stress occurring in summer or winter had small effects, but in autumn severely reduced the final yield. Autumn was the time of maximum bulking of underground storage organs in well-watered plants, and water stress which reduced assimilate production also reduced bulking. Temperature at this time was suboptimal for canopy development, and leaf area which was reduced during the stress did not increase after its relief, affecting further the growth of storage organs. Similarly, in the glasshouse experiment, plants recovered rapidly during early stages of growth, but when stress occurred later leaf area was reduced greatly, and recovery after its termination was poor. In all experiments, water deficits affected yield of storage organs but not the pattern of assimilate distribution, resulting in similar harvest indices among the plants of different watering treatments. It is concluded that the reduction in cassava yield (cv. M Aus 7) is caused by the reduction in total biomass production, and that stress occurring later in the season is most detrimental to yield because of the additional effect of reduced ability of old plants to recover leaf area after the stress is relieved.


2011 ◽  
Vol 142 ◽  
pp. 116-119
Author(s):  
De Zhong Dong ◽  
Hou Cheng Liu ◽  
Shi Wei Song ◽  
Guang Wen Sun ◽  
Ri Yuan Chen

The effect of water stress on growth and quality of bunching onion(Allium fistulosum L. var. caespitosum Makino)was studied in hydroponics by PEG treatments (10%, 15%, 20%). The results showed that the growth of bunching onion was significantly affected by water stress induced by PEG. Plant height, pseudo-stem weight, total plant weight decreased with PEG concentration increased, the inhibitions in 10% PEG and 20% PEG were greater than in 15% PEG. The root/shoot ratio increased in PEG treatments. Concentrations of allicin and pyruvic acid significantly increased at 10, 17 days after PEG treatments. With PEG concentration increased, concentrations of soluble protein increased.


2020 ◽  
Vol 11 ◽  
pp. e3196
Author(s):  
Geovani Soares de Lima ◽  
Jailson Batista da Silva ◽  
Lauriane Almeida dos Anjos Soares ◽  
Hans Raj Gheyi ◽  
Reginaldo Gomes Nobre ◽  
...  

This research aimed to evaluate the physiological indices and the accumulation of phytomass in clones of precocious dwarf cashew under salt stress during rootstock formation. The experiment was conducted in greenhouse in the municipality of Pombal-PB. The experimental design was in randomized blocks, and the treatments were organized in a 5 x 3 factorial arrangement, constituting the levels of electrical conductivity of the irrigation water - ECw (0.4 -Control; 1.2; 2.0; 2.8, and 3.6 dS m-1) and the clones of precocious dwarf cashew (Faga 11, Embrapa 51, CCP 76), with three replications and two plants per plot. Water salinity higher than 0.4 dS m-1 resulted in a decrease of the relative growth in plant height, leaf area, and phytomass accumulation in the cashew plant. The cashew clones are sensitive to water salinity from 0.4 dS m-1. Among the physiological indicators, the leaf area ratio, the sclerophylly index, and the root/shoot ratio of the precocious dwarf cashew are highlighted as salt stress indicators. The use of water with 0.4 dS m-1 of electrical conductivity is recommended for the formation of cashew rootstocks.


2008 ◽  
Vol 48 (3) ◽  
pp. 335 ◽  
Author(s):  
Colin J. Birch ◽  
David Thornby ◽  
Steve Adkins ◽  
Bruno Andrieu ◽  
Jim Hanan

Two field experiments using maize (Pioneer 31H50) and three watering regimes [(i) irrigated for the whole crop cycle, until anthesis, (ii) not at all (experiment 1) and (iii) fully irrigated and rain grown for the whole crop cycle (experiment 2)] were conducted at Gatton, Australia, during the 2003–04 season. Data on crop ontogeny, leaf, sheath and internode lengths and leaf width, and senescence were collected at 1- to 3-day intervals. A glasshouse experiment during 2003 quantified the responses of leaf shape and leaf presentation to various levels of water stress. Data from experiment 1 were used to modify and parameterise an architectural model of maize (ADEL-Maize) to incorporate the impact of water stress on maize canopy characteristics. The modified model produced accurate fitted values for experiment 1 for final leaf area and plant height, but values during development for leaf area were lower than observed data. Crop duration was reasonably well fitted and differences between the fully irrigated and rain-grown crops were accurately predicted. Final representations of maize crop canopies were realistic. Possible explanations for low values of leaf area are provided. The model requires further development using data from the glasshouse study and before being validated using data from experiment 2 and other independent data. It will then be used to extend functionality in architectural models of maize. With further research and development, the model should be particularly useful in examining the response of maize production to water stress including improved prediction of total biomass and grain yield. This will facilitate improved simulation of plant growth and development processes allowing investigation of genotype by environment interactions under conditions of suboptimal water supply.


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