Root Dry Matter Production Research Articles

Allelopathic interactions of invasive black locust (Robinia pseudoacacia L.) with secondary aliens: the physiological background

Despite of numerous benefits, black locust (Robinia pseudoacacia L.) is an invasive tree species in Slovakia and Hungary. Recently, secondary local invasions of black locust plantations by black cherry (Prunus serotina Ehrh.) and common hackberry (Celtis occidentalis L.) have been observed in these countries. In this study, we describe these unique tree-to-tree interactions directly in the field as well as simulated in the laboratory (1% water extracts from leaves and twigs applied on leaf and soil). In the field, we observed no effect on tree height and trunk diameter as well as leaf metabolic parameters caused by black cherry. However, the laboratory experiment showed a reduction in nodulation, and thus N fixation rate per plant, which did not mirror in the shoot and root dry matter (DM) production. On the other hand, common hackberry significantly affected tree height as well as leaf amino acid and total nitrogen concentration, but not the content of soluble sugars and hydrogen peroxide in the field. The laboratory experiment revealed significant reductions in nodulation, N fixation rate per plant, shoot and root DM and leaf hydrogen peroxide, nevertheless, a noticeable soluble protein accumulation. Thus, we can conclude that common hackberry, but not black cherry, can effectively suppress black locust N metabolism and growth.

Periods of water deficit after sowing cowpea

The study aimed to evaluate the germination and initial growth of semi-erect cowpea cultivars as a function of water shortfall. The experiment was conducted in experimental area of Federal University of Mato Grosso state, Brazil. Was evaluated the germination rate, foliar area, shoot and root dry matter production and diameter of the stem of the BRS Nova Era, BRS Tumucumaque and BRS Imponente, in function of four different water shortfall (0; 4; 8 and 12 days without water. The experiment delineation adopted was a factorial design 3 x 4. The cultivars BRS Tumucumaque had a higher number to sprouting seeds, shoot and root dry mass production and diameter of the stem. Perhaps the cultivar BRS Tucmucumaque had a growth sharp decline with 12 days in water shortfall.

Effect of nitrogen application on the expression of drought-induced root plasticity of upland NERICA rice

ABSTRACT This study evaluated the effect of three N fertilization levels 60 (low), 120 (medium), and 180 (high) kg N ha−1 and soil moisture content gradients created by a line-source sprinkler on the expression of plasticity in lateral root branching and dry matter production (DMP) of upland new rice for Africa (NERICA) 1 and 4. There were no significant differences in DMP between NERICA 1 and 4 under well-watered, mild drought, and severe drought conditions regardless of N level. In contrast, under moderate drought (12–21% v/v of soil moisture content [SMC] in 2011 and 16–24% v/v of SMC in 2012), NERICA 1 had significantly higher shoot dry weight, total root length (TRL), lateral root length, and branching index than NERICA 4 at medium and high N; however, there was no significant difference between the two NERICAs in DMP at low N. TRL of NERICA 1 was significantly higher under moderate drought than well-watered conditions, but only with medium and high N. Regardless of N level, moderate drought did not enhance NERICA 4’s root system. Thus, NERICA 1’s root system exhibited plastic development, promoting lateral root branching at medium and high N. These morphological changes were associated with the greater DMP in NERICA 1 than NERICA 4 under moderate drought, whereas the lack of such plasticity at low N meant genotypic differences in DMP were obscured. Our findings implied that N application can improve upland NERICA productivity under moderate drought conditions, but differences in variety and field conditions may influence efficacy.

Does the Introgression of Bt Gene Affect Physiological Cotton Response to Water Deficit?

ABSTRACT: Water deficit may affect the expression of lepidoptera-controlling proteins in cotton. However, it is unknown if there is a differential response of conventional and Bt cotton cultivars to water deficit, what could potentially affect the plant competition with weeds. The objective of this work was to investigate the response of Bt cotton cultivars to water deficit compared with their conventional near-isolines. The experiment was conducted in a greenhouse, where the cotton cultivars FMT 705, FMT 709 and IMACD 8276, with and without the Bt gene, were grown under two water regimens: 100% and 50% (moderate water deficit) of available soil water. Cotton phenology was severely affected by moderate water deficit, with a reduction in shoot and root dry matter production, root length and diameter, plant height and leaf area. No effect of the Bt gene was observed. Water deficit during cotton flowering decrease stomatal conductance, net assimilation of CO2 and transpiration rates. The leaf water potential is lower in plants exposed to a moderate water deficit compared with non-stressed plants. However, the introgression of the Bt gene does not modify cotton physiological and phenotypic response to water deficit.

Growth and Yield Performance of Foxtail Millets Under Salinity

Crop diversification in saline affected coastal areas is crucial for food security in Bangladesh. A pot experiment was conducted at polythene house at Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur-1706 during May to August, 2017 to determine the effect of salt stress on growth and yield performance of foxtail millets. Five foxtail millets genotypes viz. (i) BARI Kaon-1 (check), (ii) BD-878, (iii) BD-897, (iv) BD-891 and (v) BD-881 were tested under three salt stresses viz. (i) control (0 dS/m), (ii) 6 dS/m and (iii) 12 dS/m. Completely randomized design (CRD) with three replications was followed in the study. The growth parameter viz. stem dry matter, leaf dry matter and root dry matter production of foxtail millets genotypes were significantly varied due to salinity stresses. Salinity stresses also significantly influenced yield and yield contributing characteristics of foxtail millets. The genotypes BD-897 and BD-881 produced the higher dry matter, grains per panicle and grain yield per plants under the saline level of 6 dS/m. The higher stress tolerance index of both the genotypes demonstrate that the genotypes BD-897 and BD-881 were more salt tolerant.
 Bangladesh Agron. J. 2018, 21(1): 51-59

Effect of Different Organic Addition on Seedling Growth and Stump Quality of Teak (Tectona grandis Linn f.)

A nursery experiment was conducted to study the effect of different organic addition in the nursery on growth and stump quality of teak seedling. The nursery soil sample was analyzed before initiate the experiment and after uprooting the seedling from nursery (post harvest soil). The pre conditioned 6 months-old teak drupes (fruit with seed) were placed for germination in the nursery bed. The experiment consisted of eight treatments which replicated thrice. On 28 and 60 days after sowing, the result revealed that the application of organic amendments did not have any significant effect on number of seedlings /m2 of teak at 28 days after sowing, where as the significant influence were observed at 60 days after sowing. Significant differences were observed in root length (cm), shoot length (cm), stump weight (g), stump girth (mm) and dry matter production (g) of teak stump at 6 months after sowing. From this study it could be concluded that the organic addition of teak nursery with FYM @ 12.5 t ha-1 + bagasse fly ash @ 20 t ha-1 enhance the seedling growth and stump quality of 6 months old teak nursery.

Performance of tomato (Lycopersicon esculentum Mill.) germplasm to salinity stress

A solution culture experiment was conducted to screen out 16 Bangladeshi tomato germplasm for salinity tolerance with respect to severity of leaf symptoms, shoot and root dry matter production, fruit yield, shoot Na+, K+, Ca2+ accumulation and their respective ratios by exposing up to 120 mM NaCl. The salinity tolerance scale ranged from 1.0 (most tolerant) to 3.5 (most sensitive). Based on the severity of leaf symptoms, “BT14 (BARI Tomato 14)” and “BHT5 (BARI Hybrid Tomato 5)” were found to be most tolerant germplasm to salinity with score 1.0. Reduction of dry weight was found to be 19% (shoot) and 15% (root) in BT14 and BHT5, 30 - 76% (shoot) and 27 - 83% (root) in other germplasm. Higher correlation was found between salinity tolerance scale classes and the reduction of shoot/root dry weight, Na+ concentration, K+/Na+, and Ca2+/Na+ ratios in BT14 and BHT5 germplasm. The fruit yield of BT14 and BHT5 germplasm was less and decreases with high salinity. Thus, “BT14” and “BHT5” can be regarded as a breeding material for development of new tomato varieties resistant to salinity.

Effects of Nitrogen Forms on Root System Development, Physiological Traits, and Dry Matter Production of Rice

The objectives of this study were to evaluate the effects of nitrogen forms on root system development (expressed as total root length, nodal root number, nodal root length, and lateral root length), water use, photosynthetic rate, and dry matter production under water deficit (WD) at 20% w/w and continuously waterlogged (CWL) conditions. Rice plants cv. Nipponbare were grown in plastic pots in a vinyl house. Six N forms were applied at the same rate of 360 mg N per pot, and were prepared as follows: N-NH4+ alone (A); N-NH4+ with nitrification inhibitor (A+DCD); N-NO3- alone (N); N-NO3- with nitrification inhibitor (N+DCD); combined N-NH4+ and N-NO3- (AN); and combined N-NH4+ and N-NO3- with nitrification inhibitor (AN+DCD). The nitrification inhibitor, dicyandiamide (DCD) (C2H4N4), was applied at the rate of 100 mg pot-1. The results of the experiment showed that under both WD and CWL conditions, significant increases were seen in the root system development as expressed through total root length, nodal root number, nodal root length, and lateral root length in the N-NO3- treatments with and without DCD compared to the application of N-NH4+ treatments with and without DCD. This led to an increase in water use, and eventually a significant increase in dry matter production. Similarly, the A treatments with and without DCD also significantly increased root system development as compared with the AN and AN+DCD treatments. Furthermore, under both CWL and WD conditions, the positive and notably significant correlations between the total root length and water use, as well as between the total root length and shoot dry weight, were found only in the A and A+DCD treatments. These results indicate that rice prefers sole ammonium over the mixed ammonium-nitrate treatment, and sole nitrate applications under both WD and CWL conditions.

Morphological and kinetic parameters of the uptake of nitrogen forms in clonal peach rootstocks

Peach (Prunus persica L.) rootstock cultivars are typically selected for scion compatibility, ease of propagation, vigor, development, flowering season, yield, low need for cold temperatures, resistance to diseases, effects on the physical-chemical characteristics of the fruit, plant longevity and adaptation to adverse edaphoclimatic conditions. However, kinetic parameters related to nutrient uptake efficiency are usually not considered, such as those of nitrate (NO3−) and ammonium (NH4+). N is the nutrient that most impacts growth and yield. The objective of this study was to show the importance of the kinetic parameters of NO3− and NH4+ uptake as additional criteria for selecting peach rootstocks. The experiment was conducted in a greenhouse. Three rootstock (‘Aldrighi’, ‘Tsukuba1’ and ‘Clone 15′) were grown for 30 days in a pot containing 0.1 mol L-1 CaSO4 solution to reduce internal reserves of N. Afterwards, the plants were placed in Hoagland nutrient solution, where periodic collections of the nutrient solution were carried out for three days and the concentrations of NO3− and NH4+ were determined. After the third day of collecting the solution, the plants were collected and then separated into leaves, roots and stems. Dry matter and total N content were assessed. The kinetic parameters related to NO3− and NH4+ uptake (maximum uptake rate - Vmax, affinity constant - Km, Minimum concentration - Cmin, Influx - I) were calculated using Cinética software. The most efficient rootstock for NO3− and NH4+ uptake was ‘Tsukuba1’, as it showed the lowest values ​​of Cmin and Km and the highest values ​​of Vmax and Imax for NO3− and NH4+. NO3− uptake in ‘Tsukuba1’ and ‘Aldrighi’ showed a two-phase uptake pattern, suggesting the presence of low and high affinity transport systems. On the other hand, NH4+ uptake in the three cultivars apparently followed a one-phase uptake pattern, suggesting the presence of a high affinity transport system. The kinetic parameters of NO3− and NH4+ uptake are additional criteria that can be used in selecting peach rootstocks, as they directly influence shoot and root dry matter production and N accumulation in leaves.

Liming as a means of reducing copper toxicity in black oats

ABSTRACT: Soils which are cultivated with grapevines have high available copper (Cu) content, which can be toxic to cover crops cohabiting vineyards, such as black oats. This study aimed to assess the effect of liming in reducing Cu toxicity in black oats grown in sandy soils. Samples of a Typic Hapludalf were collected at 0-20cm, dried and subjected to the addition of Cu (0 to 50Mg kg-1) and limestone (0, 1.5, and 3.0Mg ha-1). The soil was placed in a rhizobox and black oats were grown for 30 days. We assessed root and shoot dry matter production, copper (Cu), calcium (Ca) and magnesium (Mg) contents in the tissues; Cu content in the root symplast and apoplast, as well as Cu, carbon and pH values in the rhizosphere and bulk soil. Liming reduced Cu toxicity in black oats. Cu was preferentially accumulated in the roots, mostly in the apoplast, which may be the result of a plant tolerance mechanism to prevent the transport of Cu to the shoots.

Growth and mycorrhizal colonization of maize plants treated with aqueous extracts from nonmycorrhizal weeds

Abstract: The objective of this work was to evaluate the influence of aqueous extracts of nonmycorrhizal weedy species on dry matter accumulation and assimilate partitioning of maize plants, with or without Cetraspora pellucida inoculation. The experiment was carried out in pots, in a completely randomized design, in a 5x2 factorial arrangement consisting of four plant extracts (purple nutsedge, guinea-hen weed, slender amaranth, and knotweed), a control irrigated with water, and two conditions (mycorrhizal and nonmycorrhizal maize plants), with four replicates of each treatment. Plants were irrigated with aqueous extracts diluted at 15%. Root colonization (RC), shoot dry matter (SDM), root dry matter (RDM), and RDM/SDM were evaluated. Root colonization was not influenced by the extracts, and ranged from 41.5 to 65.2%. Shoot dry matter of mycorrhizal (AM) and nonmycorrhizal (NM) plants was not influenced by the extracts; however RDM showed varying responses. Mycorrhization favored the production of RDM, and increased plant sensitiveness to the extracts. Guinea-hen weed extract increased RDM of AM plants, while the other extracts inhibited it. In NM plants, the production of RDM was benefited by slender amaranth extract, to the detriment of SDM. Mycorrhizal and nonmycorrhizal maize plants respond differently to aqueous extracts of nonmycorrhizal weeds.

CRESCIMENTO DE Ruta graveolens L. INOCULADA COM MICORRIZAS SOB DOSES DE FÓSFORO

Os fungos micorrízicos arbusculares (FMAs) são micro-organismos que fazem simbiose com raízes da maioria das plantas. O objetivo deste trabalho foi avaliar a influência dos FMAs Rhizophagus clarus e Claroideoglomus etunicatum em substrato sob baixa e ou alta dose de fósforo (P), na produção de biomassa e na acumulação de P na arruda (Ruta graveolens L.). O experimento foi conduzido no laboratório de botânica da Universidade Paranaense - UNIPAR, município de Umuarama - PR. O delineamento experimental foi inteiramente ao acaso, em fatorial 3x2, sendo os fatores: FMAs (sem FMA, com R. clarus e ou com C. etunicatum); duas doses de P (20 e 200 mg kg-1) com 8 repetições por tratamento, num total de 48 unidades experimentais (vasos de 3 L). Avaliou-se a produção de massa seca das raízes (MSR), massa seca da parte aérea (MSPA), massa seca total (MST) e o acúmulo de P na parte aérea da planta (PPA). A produção de MSR, MSPA e MST pela planta não foram significativamente afetadas apenas pela adição de P ao substrato, porém sim, pela inoculação com o FMA C. etunicatum, sob baixo e ou alto P. O acúmulo de P na parte aérea da planta foi aumentado significativamente no tratamento sem a inoculação com FMAs. Conclui-se que a inoculação com C. etunicatum é indicada para aumentar a produtividade da arruda.

Rational Water and Nitrogen Management Improves Root Growth, Increases Yield and Maintains Water Use Efficiency of Cotton under Mulch Drip Irrigation.

There is a need to optimize water-nitrogen (N) applications to increase seed cotton yield and water use efficiency (WUE) under a mulch drip irrigation system. This study evaluated the effects of four water regimes [moderate drip irrigation from the third-leaf to the boll-opening stage (W1), deficit drip irrigation from the third-leaf to the flowering stage and sufficient drip irrigation thereafter (W2), pre-sowing and moderate drip irrigation from the third-leaf to the boll-opening stage (W3), pre-sowing and deficit drip irrigation from the third-leaf to the flowering stage and sufficient drip irrigation thereafter (W4)] and N fertilizer at a rate of 520 kg ha-1 in two dressing ratios [7:3 (N1), 2:8 (N2)] on cotton root morpho-physiological attributes, yield, WUE and the relationship between root distribution and dry matter production. Previous investigations have shown a strong correlation between root activity and water consumption in the 40–120 cm soil layer. The W3 and especially W4 treatments significantly increased root length density (RLD), root volume density (RVD), root mass density (RMD), and root activity in the 40–120 cm soil layer. Cotton RLD, RVD, RMD was decreased by 13.1, 13.3, and 20.8%, respectively, in N2 compared with N1 at 70 days after planting (DAP) in the 0–40 cm soil layer. However, root activity in the 40–120 cm soil layer at 140 DAP was 31.6% higher in N2 than that in N1. Total RMD, RLD and root activity in the 40–120 cm soil were significantly and positively correlated with shoot dry weight. RLD and root activity in the 40–120 cm soil layer was highest in the W4N2 treatments. Therefore increased water consumption in the deep soil layers resulted in increased shoot dry weight, seed cotton yield and WUE. Our data can be used to develop a water-N management strategy for optimal cotton yield and high WUE.

Silicon-Mediated Alleviation of Aluminum Toxicity by Modulation of Al/Si Uptake and Antioxidant Performance in Ryegrass Plants.

Silicon (Si) has been well documented to alleviate aluminum (Al) toxicity in vascular plants. However, the mechanisms underlying these responses remain poorly understood. Here, we assessed the effect of Si on the modulation of Si/Al uptake and the antioxidant performance of ryegrass plants hydroponically cultivated with Al (0 and 0.2 mM) in combination with Si (0, 0.5, and 2.0 mM). Exposure to Al significantly increased Al concentration, mainly in the roots, with a consequent reduction in root growth. However, Si applied to the culture media steadily diminished the Al concentration in ryegrass, which was accompanied by an enhancement in root dry matter production. A reduced concentration of Si in plant tissues was also observed when plants were simultaneously supplied with Al and Si. Interestingly, Si transporter genes (Lsi1 and Lsi2) were down-regulated in roots after Si or Al was applied alone; however, both Lsi1 and Lsi2 were up-regulated as a consequence of Si application to Al-treated plants, denoting that there is an increase in Si requirement in order to cope with Al stress in ryegrass. Whereas Al addition triggered lipid peroxidation, Si contributed to an attenuation of Al-induced oxidative stress by increasing phenols concentration and modulating the activities of superoxide dismutase (SOD), catalase, peroxidase, and ascorbate peroxidase antioxidant enzymes. Differential changes in gene expression of SOD isoforms (Mn-SOD, Cu/Zn-SOD, and Fe-SOD) and the profile of peroxide (H2O2) generation were also induced by Si in Al-stressed plants. This, to the best of our knowledge, is the first study to present biochemical and molecular evidence supporting the effect of Si on the alleviation of Al toxicity in ryegrass plants.

Agronomic characterization of sweet potato accessions

The agronomic characterization of a genotype set is one of the basic steps to start a breeding program, as action strategies to search for new cultivars are defined through the knowledge of these characteristics. Thus, the aim of this study was to rescue and assess agronomic performance in accessions collected in traditional communities. Sweet potatoes were collected among “quilombos”, indigenous villages, native populations and small farmers from Vale do Ribeira. The study was conducted at UNESP, Registro Campus, from February/2013 to August/2014. The experiment was set in a randomized blocks design with 95 accessions, two commercial cultivars, Brazlândia Branca and Brazlândia Roxa (controls), with three repetitions. Total commercial roots production, percentage of commercial roots production, total roots dry matter production, roots dry matter percentage, fresh branches production, total dry matter production in branches and dry matter percentage in branches were assessed. Accessions VR13-62, VR13-61, VR13-44, VR13-11 and VR13-14 demonstrated characteristics of roots for consumption and VR13-11 and VR13-14 for industry consumption due to the high dry matter percentage obtained per hectare; VR13-35, VR13-87 and VR13-22 are adequate for animal feed purposes. VR13-11, VR13-22 and VR13-58 accessions can be used for human and animal consumption; VR13-48 was suitable for home and industry consumption; and VR13-4 and VR13-31 was suitable for animal feed and industry consumption.

Effect of salinity on germination and seedling growth of green gram varieties

Salinity tolerance is one of the important abiotic stresses that damages crop growth. In order to study the effect of saline on germination and seedling attributes, four cultivated varieties of greengram were subjected with five levels of salinity viz., 0, 4, 8 and 12 ds/m. Genotypic variation was observed for germination and seedling characters among the varieties. The experimental results revealed that with increase in salinity levels, greater reduction was observed for all the parameters. Germination per cent, seedling length, shoot, root and total dry matter production, seed vigour and salt tolerance index were found reduced in all the varieties studied with more reduction at higher salinity (12 ds/m) level rather than other lower salinity levels and shoot root ratio was found increased with increase in salinity.

Iron doses in the production of potted rosebushes

ABSTRACT: The production and quality of roses are influenced by fertilization management. The aim of this experiment was to evaluate the effects of doses of iron (Fe) in the production of potted rose bushes ( Rosa hybrida ). Treatments were based on five doses of Fe (0, 1, 3, 5 and 15mg kg-1) applied on the substrate, in a randomized block design with four replications. Seedlings presented two pairs of leaves and were individually transplanted into plastic pots (0.8dm3) containing commercial substrate. Each experimental plot consisted of a vase with a plant with two flower stalks. The following parameters were evaluated: number of leaves and flowers per flower stalk; dry matter production of roots, leaves and flowers; plant height and diameter and floral longevity. In addition, foliar levels of total chlorophyll and Fe were determined. Fertilization with Fe increases the production and quality of flowers of the rosebush cv. 'Shiny Terrazza' (r). Dose of Fe to be added to the substrate used in this study for maximum economic efficiency for this cultivar is 3.6mg kg-1.

Comparison of allelopathic potential of Sri Lankan traditional rice varieties (Oryza sativa L.) using radish (Raphanus sativus L.) as an indicator plant

Allelopathy is the direct influence of an organic substances released from one plant on the growth and development of other plants. To avoid the hazardous and indiscriminate use of chemicals for weed control in paddy fields much concerns were deposited on proper assessment and manipulation of allelopathic properties of rice plants. There is a huge variation in allelopathic potential among rice varieties. Therefore, in this experiment relay seeding technique without soil (experiment 1) and with soil as a medium (experiment 2) were conducted under laboratory condition to observe and screen the allelopathic potential of selected Sri Lankan traditional rice varieties on seed germination, shoot and root length and dry matter production of radish ( Raphanus sativus ) as a phototoxic sensitive test crop. Significant differences (p≤0.05) were observed among different rice varieties in terms of seed germination and growth inhibition of radish. The dry weight accumulation of rice cultivars ranged from 12.5-76.3% in experiment 1 and 15.9-79.9% in experiment 2. All tested varieties of rice performed inhibitions to studied characters of radish. In both experiments, the highest dry weight reductions were noticed with rice varieties Pachchaperumal and Herathbanda . Both the evaluation methods were positively correlated in determining percent reduction in all the measured parameters of radish. According to the results it can be concluded that the al-lelopathic potential of rice varieties varies in a very broad range and out of varieties tested Pachaperumal and Herathbanda showed highest allelopathic potential against radish growth.

Using swine farming wastewater for Signal grass cultivation

The objective of this study was to evaluate forage production and root accumulation in Brachiaria decumbens cv. Basilisk with swine wastewater as a fertilizer. The experiment was conducted into a greenhouse in Federal Institute of Education, Science and Technology of Southeast of Minas Gerais, Rio Pomba Campus. Pots with 6 dm-3 volumes were used as experimental units. Were used a randomized block design with four replications. Were studied four swine waste doses (0, 225, 450 and 675mL pot-1) over four regrowth cycles. The dry matter production of the aerial part, forage accumulation rate, crude protein and dry matter production of roots increased with the highest swine waste doses being around 670, 742, 160 and 465% respectively from lower to higher dose. There was interaction between swine waste and regrowth cycles for plant height and tillering, and in all regrowth cycles responded positively with increasing swine waste doses. Applying swine waste on pastures is therefore a viable alternative to increase productivity of B. decumbens cv. Basilisk, it recommends the use of swine waste corresponding to the dose of 675mL pot-1 to maintenance pastures

Seed germination and seedling growth of rice varieties as affected by flooding stress

Submergence tolerance is an important character to be considered when flash flood damages rice. Tolerant genotypes can withstand submergence for 1–2 weeks based on their tolerance level. Hence with a view to study the effect of submergence on germination and seedling attributes, eight cultivated varieties were subjected to submergence tolerance at five levels of flooding <italic>viz</italic>., 1 cm, 2 cm, 3 cm, 4 cm and 5 cm flooding levels. CR 1009 sub 1, a submergence tolerant variety was used as check. With increase in submergence levels, greater reduction was observed for all the parameters. Survival % and seedling length were found to be decreased under flooded conditions, but to a much lower extent in the tolerant genotype. Flooding decreased shoot, root and total dry matter production in all the varieties with more reduction in higher flooding (5 cm) rather than lower flooding (1cm) levels.