RESPONSE OF LISIANTHUS TO IRRIGATION WITH SALINE WATER: ION RELATIONS

Eustoma grandiflorum (Raf.) Shinn. (lisianthus) is a moderately salt tolerant species that can be produced commercially under irrigation with saline wastewaters prevalent in two salt-affected areas of California. The objective of the present studies was to determine the effect of irrigation with saline waters of two different compositions on the ion accumulation and ion relations of lisianthus ‘Pure White’ and ‘Echo Blue’. The ionic composition of irrigation waters simulated the compositions typical of i) seawater dilutions (SWD) and ii) concentrations of Colorado River water (CCRW). Electrical conductivities (EC) of SWD and CCRW were between 2 and 12 dS · m^?1. Plants irrigated with CCRW were higher in Ca²⁺ compared to plants irrigated with SWD water. Calcium was also higher in ‘Pure White’ than in ‘Echo Blue’. Increasing EC of irrigation water caused a significant decrease in shoot and leaf Ca²⁺ concentration in ‘Echo Blue’, but had no effect on Ca²⁺ content of ‘Pure White’ shoots and leaves. Magnesium concentration in ‘Echo Blue’ was higher than in ‘Pure White’. Electrical conductivity did not significantly affect Mg²⁺ concentration of either cultivar, despite the increasingly higher external concentration. Potassium concentration of young and mature leaves of ‘Echo Blue’ increased as EC increased from 2 to 8 dS · m^?1, then decreased significantly once EC exceeded 8 dS · m^?1. Potassium concentration of ‘Pure White’ leaves decreased over the range of salinity treatments tested, suggesting that the reduced potassium ion (K⁺) activity at EC levels of 8 dS · m^?1, or less, that resulted in lower leaf?K⁺ in ‘Pure White’ did not cause a decrease in K⁺ uptake in ‘Echo Blue’. Increases in external Na⁺ caused a significant increase in Na⁺ in ‘Pure White’ leaves and these plants exhibited the best growth even when levels of Na⁺ were high enough to be considered detrimental for growth.     

GROWTH AND BIOMASS PARTITIONING IN TOMATO IN RELATION TO RATIO OF NITROGEN:PHOSPHORUS SUPPLY

Tomato (Lycopersicon esculentum) plants were grown in hydroponic culture with nitrogen (N): phosphorus (P) supply ratios from 18:1 to 2:1. Nitrate and phosphate were supplied daily in pre-set ratios to maintain a constant P concentration, giving varying degrees of N limitation. Plant dry weight, weights of plant fractions and N and P concentrations in plant parts were measured at 9 and 18 days. Relative growth rate was related to ratio of N:P supplied, with higher ratios giving a higher growth rate, but a noticeably reduced rate was only apparent at 4:1 and 2:1 ratios. Relative growth rate was largely independent of internal N and P concentrations, although there was an optimum internal N:P ratio of approximately 14:1. The plants took up N and P at rates adjusting towards this 14:1 ratio. Depressed relative growth rate of plants inadequately supplied N was linearly correlated with decreased shoot fraction.     

GROWTH,YIELD, AND ION RELATIONS OF STRAWBERRY IN RESPONSE TO IRRIGATION WITH CHLORIDE-DOMINATED WATERS

Strawberry is listed as the most salt sensitive fruit crop in comprehensive salt tolerance data bases. Recently, concerns have arisen regarding declining quality of irrigation waters available to coastal strawberry growers in southern and central California. Over time, the waters have become more saline, with increasing sodium (Na⁺) and chloride (Cl^?). Due to the apparent extreme Cl^? sensitivity of strawberry, the rising Cl^? levels in the irrigation waters are of particular importance. In order to establish the specific ion causing yield reduction in strawberry, cultivars ‘Ventana’ and ‘Camarosa’ were grown in twenty-four outdoor sand tanks at the ARS-USDA U. S. Salinity Laboratory in Riverside, CA and irrigated with waters containing a complete nutrient solution plus Cl^? salts of calcium (Ca²⁺), magnesium (Mg²⁺), Na⁺, and potassium (K⁺). Six salinity treatments were imposed with electric conductivities (EC) = 0.835, 1.05, 1.28, 1.48, 1.71, and 2.24 dS m^?1, and were replicated four times. Fresh and dry weights of ‘Camarosa’ shoots and roots were significantly higher than those of ‘Ventana’ at all salinity levels. Marketable yield of ‘Camarosa’ fruit decreased from 770 to 360 g/plant as salinity increased and was lower at all salinity levels than the yield from the less vigorous ‘Ventana’ plants. ‘Ventana’ berry yield decreased from 925 to 705 g/plant as salinity increased from 0.835 to 2.24 dS m^?1. Relative yield of ‘Camarosa’ decreased 43% for each unit increase in salinity once irrigation water salinity exceeded 0.80 dS m^?1. Relative ‘Ventana’ yield was unaffected by irrigation water salinity up to 1.71 dS m^?1, and thereafter, for each additional unit increase in salinity, yield was reduced 61%. Both cultivars appeared to possess an exclusion mechanism whereby Na⁺ was sequestered in the roots, and Na⁺ transport to blade, petiole and fruit tissues was limited. Chloride content of the plant organs increased as salinity increased to 2.24 dS m^?1 and substrate Cl increased from 0.1 to13 mmol_cL^?1. Chloride was highest in the roots, followed by the leaves, petioles and fruit. Based on plant ion relations and relative fruit yield, we determined that, over the range of salinity levels studied, specific ion toxicity exists with respect to Cl^?, rather than to Na⁺ ions, and, further, that the salt tolerance threshold is lower for ‘Camarosa’ than for ‘Ventana’.     

NUTRIENT AND GROWTH RESPONSES OF LEERSIA ORYZOIDES,RICE CUTGRASS,TO VARYING DEGREES OF SOIL SATURATION AND WATER NITROGEN CONCENTRATION

Leersia oryzoides (rice cutgrass) is an obligate wetland plant common to agricultural drainage ditches. The objective of this greenhouse study was to expose plants to various flooding and aqueous nitrogen (N) concentrations and then to quantify the allocation of nutrients and biomass to plant components. Plants in the continuously flooded treatment (CF) had the highest tissue concentrations of copper (Cu), sulfur (S), zinc (Zn), potassium (K), sodium (Na), and manganese (Mn) in one or more plant components. Plants in the partially flooded treatment (PF) had the highest concentrations of magnesium (Mg) in leaves. The N input affected phosphorus (P) and S concentrations in roots. Leaf, stem, and root biomass were highest in PF plants. Rhizome biomass was the lowest in CF plants. These results indicate that L. oryzoides may significantly affect elemental concentrations in surface waters by its ability to uptake various elements and subsequent sequestration in various biomass components.     

不同水稻品种对钾的吸收及其对钾肥的反应

测定了９个水稻品种在０．１ｍｍｏｌ／ＬＫ２ＳＯ４＋０．２ｍｍｏｌ／ＬＣａＳＯ４溶液中吸收２小时和４小时的Ｋ＾＋浓度和ＰＨ值的变化。结果表明溶液的ＰＨ变化与Ｋ＾＋浓度变化呈极显著的正相关，这为建立快速简便地筛选高吸钾速率水稻品种的方法提供了基础。幼苗耗竭试验表明，水稻利用土壤中的钾大部分来自非交换性钾源。各品种的吸钾总量与来自非交换性钾及１ｍｏｌ／ＬＨＮＯ３不能撮的钾和矿物钾均有极显著的相关性，这可     

ALLOCATION OF NITROGEN AND DRY MATTER FOR TWO SOYBEAN GENOTYPES IN RESPONSE TO WATER STRESS DURING REPRODUCTIVE GROWTH

Drought stress significantly limits soybean [Glycine max (L.) Merr.] yield in the Southeastern United States. The Plant Introduction 416937 (PI), which has lower yields than adapted cultivars under favorable conditions but a relatively lesser yield reduction under water-stress conditions, has been identified as a potential source of drought avoidance germplasm. It is unclear whether the mechanism of drought avoidance is associated with shoot or root. Also unclear is the effect of the PI's restricted yield potential on the extent of its yield reduction in response to a water stress. To determine the differences in response between the PI and an adapted cultivar, Deltapine 105, to reproductive sink size and water stress, inoculated PI and Deltapine plants were grown in sand-filled pots in controlled-environment chambers. The fixed rooting volume of the pot culture restricts the influence that genotypic differences in rooting patterns may have in accessing soil water. During the 24-day period of pod development between R-3 and R-6 growth stages, plants were subjected to one of two water regimes, either well-watered or water-stressed to a leaf water potential of about ?0.95 MPa. Within each water treatment, plants of both genotypes were depodded at the R3 stage to remove all pods (full depodding), one-half of the pods (partial depodding), or no pods (no depodding). Tissues of plants harvested at the R6 stage were separated, dried to a constant mass, weighed, and analyzed for nitrogen. Photosynthate production was calculated from dry matter and nitrogen content. Photosynthate production and nitrogen fixation by Deltapine plants were unaffected within a pod load by the mild water stress, but both photosynthate production and nitrogen fixation by the PI plants were diminished by the mild water stress except when a reproductive sink was absent. It thus appears that a sizeable component of the drought tolerance observed in field experiments for the PI plants may be attributed to root characteristics. Leaf nitrogen concentration decreased during water stress in Deltapine plants but not in the PI plants. Also, the decrease in nitrogen concentration in stems was greater in response to increased reproductive load for Deltapine plants than for the PI plants. These data suggest that the PI does not remobilize leaf nitrogen as readily as Deltapine.     

RESPONSE OF LIME THYME TO SALINITY AND IONIC CONCENTRATION IN NUTRIENT SOLUTION

□ Plants from 60-day-old Lime Thyme (Thymus citriodorus) cuttings were potted in a medium of coconut fiber and peat moss and were treated with three different nutrient solutions: T1, T2, and T3. T1 was a standard nutrient solution; T2 was incremented with macronutrients up to an electrical conductivity (EC) of 2.8 dS m^?1; and T3 was the same as T1 but incremented up to an EC of 2.8 dS m^?1 with sodium chloride. The plants were then grown for 90 days in a greenhouse with natural daylight in Almería, Spain. Root growth was not affected by the treatments. The dry weight of the leaves and the total dry weight of the plants benefited from the salinity. The specific salinity of the sodium chloride negatively affected growth compared to the same salinity in the complete nutrient solution.     

INTERACTION BETWEEN POTASSIUM CONCENTRATION AND ROOT-ZONE TEMPERATURE ON GROWTH AND PHOTOSYNTHESIS OF TEMPERATE LETTUCE GROWN IN THE TROPICS

Lactuca sativa L. plants were grown at three root-zone temperatures (RZTs): 25°C, 30°C and ambient RZT (A-RZT) on an aeroponic system. Three potassium (K) concentrations: ?25% (minus K), control (standard K), and +25% (plus K) were supplied to plants at each RZT. Plants grown at the plus K and 25°C-RZT had the highest productivity, largest root system and highest photosynthetic capacity. The minus K plants at 25°C-RZT had the highest shoot soluble carbohydrate (SC) concentration, but they had the highest root SC concentration in the plus K plants at A-RZT. However, the highest starch concentration was found in both shoots and roots of the plus K plants at 25°C-RZT. The plus K plants had the highest shoot K concentration at 25°C-RZT, but they had the highest root K concentration at A-RZT. Highest proportion of absorbed K was partitioned to shoots when the plants were grown with the plus K at 25°C-RZT.     

A NEW STRATEGY TO ENRICH CALCIUM NUTRITION OF FRUIT: SYNERGISTIC EFFECTS OF POSTHARVEST FOLIAR CALCIUM AND BORON SPRAYS

The objective of the study is to investigate the role of calcium (Ca) and boron (B) synergy in higher maintenance of Ca in fruit buds during senescence. To study the hypothesis, an experiment was conducted for two years in two ‘Starking Delicious’ apple (Malus domastica Borkh.) orchards established on seedling rootstocks in Banaz, Usak, Turkey. Treatments composed of postharvest foliar sprays of Ca at rate of 15.13 kg h^?1, B at rate of 2.47 kg h^?1 and their combination (Ca+B) compared with control trees sprayed with water. Fruiting spurs, flower ovaries, young and mature fruits were sampled and analyzed for their Ca, B, potassium (K) and magnesium (Mg) contents. Fruit were stored for six months and quality attributes were studied. Results put forth that Ca+B treatments significantly increase fruit Ca and B concentrations and firmness. The results displayed that postharvest B spray improves Ca nutrition of fruits through synergism of Ca+B on Ca translocation.     

NATURAL ABUNDANCES OF 15NITROGEN AND 13CARBON INDICATIVE OF GROWTH AND N2 FIXATION IN POTASSIUM FED LENTIL GROWN UNDER WATER STRESS

Dual natural abundance analysis of ¹⁵Nitrogen (N) and ¹³Carbon (C) isotopes in lentil plants subjected to different soil moisture levels and rates of potassium (K) fertilizer were determined to assess crop performance variability in terms of growth and N₂-fixation (Ndfa). The δ¹⁵N values in lentils ranged from +0.67 to +1.36‰; whereas, those of the N₂-fixed and reference plant were ?0.45 and +2.94‰, respectively. Consequently, the Ndfa% ranged from 45 and 65% of total plant N uptake. Water stress reduced Δ¹³C values. However, K fertilization enhanced whole plant Δ¹³C along with dry matter yield and N₂-fixation. The water stressed plants amended with K fertilizer seemed to be the best treatment because of its highest pod yield, high N balance, and N₂-fixation with low consumption of irrigation water. This illustrates the ecological and economical importance of K fertilizer in alleviating water stress occurring during the post-flowering period of lentil.     

基本苗数和底追肥比例对冬小麦籽粒产量和蛋白质组分的影响

以中任1号小麦为试验材料,采用二因素随机区组设计,研究了基本苗和氮肥施用策略对小麦植株性状、产量和蛋白质组分的影响。结果表明,不同基本苗数和氮肥底/追比例的处理间株高、穗长、产量、千粒重、容重均有显著差异。穗长与穗粒数呈极显著正相关(r=0.931**)。随基本苗增加,穗长、穗粒数和千粒重逐渐减少,处理间差异显著。容重有随基本苗增加而升高的趋势。对产量而言,基本苗以450万/hm2时较高,但与300万/hm2和375万/hm2基本苗处理间的产量差异不显著,因此,生产中在偏晚的播期内,可以根据实际播种时间和地力条件,在300~450万/hm2基本苗范围内进行调整。不同蛋白组分对基本苗处理的反应有别,在基本苗较少时清蛋白和球蛋白含量较低,而谷蛋白和总蛋白含量较高。清蛋白、球蛋白、醇溶蛋白在各追肥比例处理间差异不显著,谷蛋白和总蛋白含量处理间差异显著,且均以底追比例3∶7的处理含量最高。总蛋白含量有随追肥比例增加而提高的趋势。     

EFFECT OF SWINE MANURE EXTRACT ON LEAF NITROGEN CONCENTRATION,CHLOROPHYLL CONTENT,TOTAL POTASSIUM IN PLANT PARTS AND STARCH CONTENT IN FRESH TUBER YIELD OF CASSAVA

The effects of swine manure extract (SME) as foliar fertilizer (FSME), soil fertilizer (SSME), and both soil and foliar fertilizer (FNSSME) on leaf nitrogen (N) concentration, chlorophyll content, total potassium (K) in plant parts and starch content in the fresh roots, compared to a conventional, chemical fertilizer (CF) were studied in cassava cultivar ‘Hauybong 60’. The results showed that plants on FNSSME had the highest chlorophyll contents and SPAD values at four months after planting (MAP). Cassava plants treated with SSME and FNSSME had highest starch content and was significantly higher than in plants treated with CF and a FSME. There was a strong, positive relationship between the leaf nitrogen concentration and chlorophyll content in cassava at 6 MAP. The results of the study indicated that an application of FNSSME to cassava plants could provide a higher chlorophyll content and higher tuber quality of the plants than those applied with chemical fertilizer.     

RESPONSE OF MAIZE GENOTYPES TO SEVERAL MYCORRHIZAL INOCULUMS IN TERMS OF PLANT GROWTH,NUTRIENT UPTAKE AND SPORE PRODUCTION

A greenhouse experiment was conducted at the University of Çukurova, Rhisosphere Lab, Adana, Turkey, on a growth medium to assess the impact of several selected mycorrhiza including indigenous AMF-maize hybrid combinations on spore production, plant growth and nutrient uptake. In the experiment, six maize (Zea mays L.) (Luce, Vero, Darva, Pegasso, P.3394, and P.32K61) genotypes were used. Control, Glomus mossea, G. caledonium, G. etunicatum, G. clarium, G. macrocarpum, G. fasciculatum, G. intraradices, Dr. Kinkon (Japanese species), indigenous mycorrhizae (Balcal? series) and cocktail mycorrhizae species spores were used. The growth of maize genotypes was found to depend on the mycorrhizal species. For shoot and root dry weight production G. intraradices is one of the most efficient mycorrhiza species on average on all maize genotypes. Genotypes P.3394 and P.32K61 produced the highest shoot and root dry weight as well. Pagasso and Darva genotypes compared to the other genotypes have high root colonization percentages. On average G. clarium inoculated plants also have high percentages of root colonization. It has been found that the P.32K61 genotype has a high phosphorus (P)% content and Pagasso genotypes have higher zinc (Zn) content uptake than other genotypes. G. clarium inoculated maize genotype plant tissues have high P% and Zn content. G. intraradices is also efficient for P and Zn uptake. Mycorrhizal dependent maize genotypes showed variability in P efficiency from inefficient to efficient genotypes.     

NaCl和NaHCO3胁迫下马蔺生长与光合特性的反应

采用室内水培实验,以马蔺(Iris lactea Pall.var.chinensis(Fisch.)Koidz.)为研究对象,探讨盐(NaCl)、碱(NaHCO3)胁迫对植株生长、水分状况、质膜透性、叶片叶绿素含量和光合特性的影响,初步比较盐碱胁迫效应的差异。结果表明,在相同Na+浓度下,NaHCO3胁迫组对马蔺生长的抑制、细胞质膜透性的破坏以及叶绿素含量的减少程度均明显大于NaCl胁迫组,这可能是因为碱性盐胁迫下特有的高盐和高pH的共同作用。同时,盐碱胁迫对茎叶生长的抑制作用大于根系,对鲜重的影响大于干重。随着胁迫浓度的增加和胁迫时间的延长,马蔺叶片叶绿素含量显著降低。同时,叶片的电解质外渗率与植株含水量呈显著负相关。碱性盐胁迫下马蔺光合速率下降主要受非气孔限制,而中性盐胁迫下既有气孔限制,又有非气孔限制。     

EFFECT OF THE ECTOMYCORRHIZAL FUNGUS PAXILLUS INVOLUTUS ON GROWTH AND CATION (POTASSIUM,CALCIUM, AND MAGNESIUM) NUTRITION OF PINUS SYLVESTRIS L. IN SEMI-HYDROPONIC CULTURE

A semi-hydroponic culture was used to compare growth and cation nutrition of mycorrhizal (Paxillus involutus) and non-mycorrhizal Scots pine seedlings. When roots and hyphae grew together, concentrations and contents of macronutrients in needles and roots were not significantly different between mycorrhizal and non-mycorrhizal plants. When grown in two separate compartments, root potassium (K) concentrations, concentrations and contents of calcium (Ca) in needles and roots, needle nitrogen (N) concentrations, total N content and contents of root K and Mg were significantly reduced in mycorrhizal plants. Whereas ¹⁵N abundance increased in roots of mycorrhizal plants. The results indicated that the extraradical mycelium of the fungus strain used was able to transport N to the plant but did not contribute to long-term cation uptake and growth of host plants. An insufficient supply of macro-elements [N, phosphorus (P)] may account for the reduced growth of mycorrhizal plants and the differences in cation uptake between mycorrhizal and non-mycorrhizal plants.     

PHENOLOGY AND SEED QUALITY RESPONSE OF RAPE (B. NAPUS) VERSUS MUSTARD (B. JUNCEA) TO SULFUR AND POTASSIUM FERTILIZATION IN NORTHWEST PAKISTAN

Inappropriate sulfur and potassium fertilization, particularly with continued soil nutrient mining and yearly fluctuations in rainfall, are major factors contributing to slow growth and low seed quality of canola in northwestern Pakistan. A field experiment was conducted in 2007–2008 on a sulfur (S) and potassium (K) deficient clay loam soil under irrigation at the research farm of NWFP (Northwest Frontier Province) Agricultural University, Peshawar, Pakistan, with an objective to determine response of phenology and seed quality of Brassica oilseed rape versus mustard to S and K fertilizer application. Twenty treatments in a randomized complete block design were consisted of two oilseed genotypes [rape (B. napus canola) and mustard (B. juncea canola)], at three rates each of S (15, 30, and 45 kg S ha^?1) and K (30, 60, and 90 kg K ha^?1), plus control (no K and S applied). Days to flowering, pod formation, seed filling duration and maturity were enhanced with K and S fertilization compared to control plots. The species B. napus took more time to flowering, pod formation, seed filling duration and maturity compared to B. juncea. Both genotypes responded positively for seed quality (oil and protein content) to K and S fertilization, but the magnitude of response varied with level and combination of K and S fertilization. Delay in the phenological stages showed negative relationship with oil and protein content in seed of both genotypes. It is concluded that a combination of 60 kg K ha^?1 + 30 kg S ha^?1 would accelerate phenological development and improve seed quality of rape and mustard in the study area.     

SEED YIELD AND YIELD COMPONENTS RESPONSE OF RAPE (B. NAPUS) VERSUS MUSTARD (B. JUNCEA) TO SULFUR AND POTASSIUM FERTILIZER APPLICATION IN NORTHWEST PAKISTAN

Improper sulfur (S) and potassium (K) fertilizer management, particularly with continued soil nutrient mining, is one of the major factors contributing to low seed yield of canola in northwestern Pakistan. A field experiment was conducted in 2007?2008 on a S and K deficient clay loam soil at the Research Farm of NWFP (Northwest Frontier Province) Agricultural University, Peshawar, Pakistan, with an objective to determine seed yield and yield components response of Brassica oilseed rape versus mustard to S and K application. Twenty treatments in a randomized complete block design were consisted of two oilseed rape (B. napus canola) and mustard (B. juncea canola) genotypes at three rates each of S (15, 30, and 45 kg S ha^?1) and K (30, 60, and 90 kg K ha^?1) fertilizers plus one control (no S and K applied). Seed yield and yield components increased significantly with K and S fertilization as compared to the zero-S/zero-K control. Both genotypes responded positively for seed yield and yield components to K and S fertilization, but the magnitude of response varied with levels of S and K, as well as combined K + S applications. It is concluded that a combination of 60 kg K + 30 kg S ha^?1 would improve seed yield and yield components of rape and mustard in the study area and contribute significantly to increased production. Growing B. napus was better than B. juncea in the study area, because B. napus produced significantly higher seed yield and yield components than B. juncea, indicating that yield components are the most important criteria for selection of Brassica genotypes for higher seed yield.     

VARIATIONS IN ECOSYSTEM SERVICE VALUES AND LOCAL ECONOMY IN RESPONSE TO LAND USE: A CASE STUDY OF WU'AN,CHINA

In an industrial/mining city, land use, ecosystem service values (ESVs) and local economy have a close relation. The study reported in this paper is conducive to optimising land use and to balancing ecosystem services and local economy. The aim is to provide useful information and advice for industrial/mining cities concerned with sustainable development. Wu'an, which is rich in mineral resources and an important energy supplier in Hebei Province, is selected as the study area. The ecosystem service value coefficients of industrial ecosystem and urban ecosystem are estimated adopting the cost method and applied to the city from 1996 to 2005. The temporal and spatial changes of the ESVs estimated within the entire ecosystem, sub‐ecosystems and individual ecosystem services are analysed and discussed based on land use. The results show that land use in Wu'an had a great influence on the ESVs and especially the project of converting farmland into forests determined the entire ecosystem structure and functions. Additionally, the study shows the comparing relationships between ecosystem service values and local economy through various mathematical expressions. One significant relationship can be abstracted into an inverse curve (zone) under restrained conditions. The conclusions suggest that the rapid local economy development should build on a reasonable land use with emphasis on the high ecosystem services. Copyright © 2011 John Wiley & Sons, Ltd.     

RESPONSE OF FRIJOLILLO RHYNCHOSIA MINIMA (L) DC. TO SUPPLEMENTARY PHOSPHORUS WITH THREE SOIL MOISTURE CONDITIONS: I. GROWTH AND DEVELOPMENT

This study was undertaken with the objective of evaluating the response of frijolillo, grown with three levels of soil moisture and supplemented with phosphorous (P). The experiment was carried out under greenhouse conditions without climate control. Plants were tested during the period from germination to vegetative growth stage. Three soil moisture levels (100, 50, and 25% of field capacity) combined with four levels of P (0, 50, 100, and 150 mg kg^?1) were tested in a factorial arrangement with four replications. This species showed tolerance to drought stress since its leaf area, dry mass of stems and root mass did not decrease with 50% of constant moisture. Furthermore, with the highest concentrations of phosphorous (100 and 150 mg kg^?1) there was more aerial mass accumulation. Finally, with maximum drought stress (25% moisture) growth of main stem decreased. However, root growth had a maximum length under the lowest moisture conditions.