Printer Friendly

Ecological significance of root anatomy in date palm (Phoenix dactylifera) cultivars from diverse origins.

Byline: Ghayoor Fatima Iqrar Ahmad Khan Muhammad Jaffar Jaskani and Fakhara Khanum

Abstract

Date palm (Phoenix dactylifera L.) is one of the major fruit crops in Pakistan and country ranks among the seven leading producers worldwide. It shows wide variations in its morpho-anatomical characteristics. For root anatomical studies twenty two date palm cultivars were collected from Date Palm Research Station Jhang Pakistan and were cross-sectioned free hand. Root parameters were measured with the help of using a compound microscope. Results showed that sclerenchyma thickness sclerenchyma bundle area and cortical cell area were largest in Zaidi (305.40; 18950.3; 5174.6 m) while Karbalaen (62.63 m) Khudrawi-2' (2867.0 m) and Saib (1206.2 m) showed smallest values respectively. Highest cortical thickness metaxylem area and phloem area were observed in Makran. All the cultivars displayed significant variations in the root structures which indicate different evolutionary routes for date palm cultivars. Further molecular genetics studies are needed to decipher the diversity in date palm cultivars. Copyright 2014 Friends Science Publishers

Keywords: Diversity; Endodermis; Epidermis; Metaxylem; Sclerenchyma.

Introduction

Pakistan is one of the biggest producers of dates (Phoenix dactylifera L.) on the global scale (Markhand et al. 2010). About 325 varieties of date palm are introduced from several native and exotic sources in Pakistan (Jamil et al. 2010) and country's date production was above 557 metric tonnes and cultivation area was93088 ha in 2011 (FAO 2011). It is one of the oldest fruit trees and widely cultivated for its edible syrupy fruit. Having long history of date palm cultivation its exact native distribution is unidentified but perhaps instigated somewhere in southwest Asia and possibly also from the desert of northern Africa (El-Shibli and Korelainen2009).Development of the root structure is considered important in the survival and growth of date palm (Ogburn and Edward 2009). Differentiation of root cortex proves key factor in controlling the transport of water and nutrients inside and outside of the root and subsequently to other parts of the plant body. Endodermis the internal layer of cortex acts like an apoplastic barrier and is crucial for selective transport in the stele (Clarkson and Robards1975). Like endodermis the exodermis also has the properties of the apoplastic barrier but it is differentiated in sub epidermal layer of cortex periphery. It enables exodermis to protect the tissue of middle part of cortex (Zimmerman and Steudle 1998).Formation of aerenchyma may enhance diffusion of the photosynthetic and atmospheric oxygen from shoot to roots (Baruch and Merida 1995; Hameed et al. 2009). Compactness of exodermal and hypodermal layers in the roots can play active role in preventing the collapse of cortex and prove important structural framework for the aereanchyma formation (Seago and Marsh 1989).Anatomical characteristics greatly help in the identification of plant species and cultivars. Structural modifications are important in assessing degree of tolerance in plant species against a variety of environmental stresses in addition to other physiological and biochemical processes (Hameed et al. 2009). Abiotic stresses result in changes in structure size and nature of different plant tissues which contribute in adaptation to unfavourable environmental conditions (Patakas 2012).Keeping in view the above considerations the present study was designed to report the comparison between root anatomical structures of different cultivars of date palm which have been introduced from different origins. Structural modification in the root of date palm has been studied in relation to their productivity and tolerance to environmental stresses.

Materials and Methods

The date palm cultivars in Date Palm Research Station Jhang have been introduced not only from all over Pakistanbut also from Saudi Arabia Iran Iraq and Egypt. Root anatomical structures of 22 cultivars i.e. Aseel Berehmi Karbalaen Khudrawi-1 Khudrawi-2 Koharba Kokna Kuzanabad Makraan Neelam Peela Dora Peeli Sundar Qantar Rachna Saib Shado Shamran Shamran-2 Wahan Wali Zaidi Zardu and Zeerin were studied to know the diversity in them.A sample of adventitious roots was collected from each cultivar and immediately placed in polythene bags. A 2 cm piece form the root-shoot junction was taken for root anatomy and placed in FAA (formalin acetic alcohol) solution which contained v/v 5% formalin 10% acetic acid50% ethanol and 35% distilled water. For long-term preservation the material was subsequently transferred to acetic alcohol solution (acetic acid 25% ethanol 75%).Free hand sectioning technique was done for the preparation of permanent slides of root transverse sections. The sections were passed through a series of ethanol grades for dehydration (Ruzin 1999). For staining safranin and fast green were applied. The sections were finally mounted in Canada balsam for permanent slides. The sections werephotographed with the help of camera-equipped compoundmicroscope. Measurements of anatomical parameters were taken with the help of ocular micrometer under a compound microscope which was calibrated with the help of stage micrometer. CRD experimental design was applied and collected data on dermal ground and vascular tissues subjected to ANOVA and means were compared by Duncan's multiple range (DMR 0.05).

Results

Different root anatomical parameters i.e. Epidermis thickness Epidermis cell area Sclerenchyma thickness Sclerenchyma area Sclerenchyma bundle area Cortical region thickness Cortical cell area Endodermis thickness Endodermis cell area Phloem area Pith area Metaxylem area and Vascular region thickness were measured (Table I). Root sections of all cultivars were labelled (Fig. 1) as Aseel (Fig. 1a) Berehmi (Fig. 1b) Karbalaen (Fig. 1c) Khudrawi-1 (Fig. 1d) Khudrawi-2 (Fig. 1e) Koharba (Fig. 1f) Kokna (Fig. 1g) Kuzanabad (Fig. 1h) Makraan (Fig. 1i) Neelam (Fig. 1j) Peela Dora (Fig. 1k) Peeli Sundar (Fig. 1l) Qantar (Fig. 1m) Rachna (Fig. 1n) Saib (Fig. 1o) Shado (Fig. 1p) Shamran (Fig. 1q) Shamran-2 (Fig. 1r) Wahan Wali (Fig.1s) Zaidi (Fig. 1t) Zardu (Fig. 1u) and Zeerin (Fig. 1v). All the cultivars had very specific anatomical features which help in their taxonomic identification and also indicate their adoption to a variety of environmental conditions. Variation in values of root structures and comparative characteristics of all cultivars are described below.

Epidermis Thickness

Epidermis thickness varied significantly (Pless than 0.01) in all the cultivars of date palm (Table 1). Maximum epidermisthickness was found in Berehmi (57.19 m) followed by Kozanabad (53.85 m) while minimum thickness was observed in Karbalaen (19.06 m).

Sclerenchyma Thickness

Sclerenchyma thickness in all 22 cultivars varied significantly (Pless than 0.01) from each other (Table 1). Zaidi showed the highest Sclerenchyma thickness (305.40 m) followed by Zardu (305.01 m). In contrast to this Karbalaen (62.63 m) showed lowest sclerenchyma thickness.

Cortical Region Thickness

Variations according to the cortical region thickness were significant (Pless than 0.01) in all the studied cultivars (Table 1). More than half of cultivars showed the cortical region thickness greater than 500 m. Makraan had the highest cortical region thickness (898.60 m) followed by Khudrawi-1 (814.20 m) as Kokna had the lowest cortical region thickness (288.60 m).

Endodermis Thickness

Endodermis thickness varied significantly (Pless than 0.01) in all the studied cultivars (Table 1). The largest endodermis thickness was observed in Saib (49.02 m) followed by Makraan (43.50 m) while the lowest value was recorded for Neelam (19.00 m).

Vascular Region Thickness

The vascular region thickness in all cultivars varied significantly (Pless than 0.01). Neelam showed the highest vascular region thickness (735.30 m) followed by Zardu (718.90m). However Zeerin had the smallest vascular region thickness (337.60 m; Table 1).

Epidermis Cell Area

Variation regarding epidermis cell area in all cultivars was highly significant (Pless than 0.01). Berehmi showed the utmost cell area (2464.90 m2) followed by Shamran-2 (1538.40 m2) and Makraan (1538.40 m2). In contrast to this Wahan Wali showed greatly reduced epidermal cells values (681.79 m2; Table 2).

Sclerenchyma Area

Sclerenchyma area was significantly (Pless than 0.01) varied in all studied cultivars (Table 2). Khudrawi-2 (3811.00 m2) surpassed all other cultivars in having maximum sclerenchyma area followed by Rachna (1328.60 m2) whereas minimum sclerenchyma area was recorded in Kokna (209.78 m2).Sclerenchyma Bundle Area

Sclerenchyma bundle area varied significantly (Pless than 0.01) in all cultivars (Table 2). Maximum of values of sclerenchyma bundle area was observed in Zaidi (18950.30m2) whilst Khudrawi-2 (2867.00 m2) possessed minimum area.Cortical Cell Area

Variations regarding cortical cell area in all cultivars were varied significantly (Pless than 0.01; Table 2). Zaidi (5174.60 m2) had highest cell area followed by Rachna (5017.20 m2) while Saib had similar minima (1206.20m2).

Table 1: Comparison of means of Epidermis Sclerenchyma Cortical region Endodermis and Vascular region

thickness of root parameters of date palm cultivars

###Sclerenchyma thickness Cortical region thickness###Vascular###region

Cultivars###Epidermis thickness (m)###Endodermis thickness (m)

###(m)###(m)###thickness (m)

Aseel###27.23HIJ###196.0C D###738.00BC DE###24.50GHI###343.10IJ

Berehmi###57.19A###125.27IJ###659.00DEFGH###29.90EFG###438.40FGHE

Karbalaen###19.06J###62.63LM###566. 40GHIJK###24.50GHI###517.40EF

Khudrawi-1###27.23HIJ###239.65B###814.20AB###24.50GHI###599.10C DE

Khudrawi-2###35.40EFGH###239.65 B

###648.10 DEFGHI

###24.50GHI###452.00FG

Koharba###43.57C DE###70.80KLM###408.50KLMNO###32.60DEF###381.20GHIJ

Kokna###40.80CDEF###253.27 B###288.60O###24.50GHI###585.50C DE

Kozanabad###53.85AB###160.67EFGH###806.10ABC###40.80BC###354.00HIJ

Makraan###32.68FGHI###70.80KLM###898.60A###43.50AB###514.70EF

Neelam###35.40EFGH###144.33FGHI###639.90DEFGHI###19.00I###735.30A

Peela Dora###29.95GHI###141.61GHI###697.10BC DEFG###24.50GHI###343.10IJ

Peeli Sundar###38.10DEFG###122.55IJ###612.70EFGHIJ###21.70HI###345.80HIJ

Qantar###35.40EFGH###136.16HI###590.90FGHIJ###24.50GHI###348.50HIJ

Rachna###29.95GHI###185.18C DE###490.20JKLM###24.50GHI###345.80HIJ

Saib###35.40EFGH###166.12EFG###514.70IJKL###49.00A###582.70C DE

Shado###35.40EFGH###209.69E###599.10FGHIJ###24.50GHI###411.20GHIJ

Shamran###38.10DEFG###89.87KLM###698.90BC DEF###32.60DEF###452.00FG

Shamran-2###29.95GHI###87.14KLM###680.80C DEFGH###24.50GHI###422.10GHIJ

Wahan Wali###38.10DEFG###89.87KLM###354.00NO###38.10BCD###375.80GHIJ

Zaidi###40.80C DEF###305.40H###675.30C DEFGH###40.80BC###460.20FG

Zardu###40.80C DEF###305.01A###767.90BC D###24.50GHI###718.90AB

Zeerin###49.02BC###89.87KLM###577.30FGHIJ###35.40CDE###337.60 J

Table 2: Comparison of means of various root parameters for 22 date palm cultivars (m2)

###Epidermis###cell Sclerenchyma###Sclerenchyma###Cortical###cell###Endodermis###Phloem###area###Pith###area###Metaxylam area

Cultivars

###area (m2)###area (m2)###bundle area (m2)###Area (m2)###cell area (m2)###(m2)###(m2)###(m2)

Aseel###996.40BCDE###506.97EF###8198.90CDEFG###1888.00DEFG###367.10 DE###3356.50FGHIJK###36.50AB###2797.00GH

Berehmi###2464.90A###594.38DEF###5646.60EFGH###1992.90DEFG###524.40CDE###6520.70BCD###32.80BC###10716.30DEF

Karbalaen###699.20DE###576.90EF###5052.20EFGH###2220.10CDEFG###367.10DE###2325.00JK###20.93D###2727.10GH

Khudrawi-1###716.70DE###594.38DEF###6922.80EFG###3146.70CDEF###367.10DE###4335.40DEFGHIJK###25.60CD###3863.40GH

Khudrawi-2###996.40BCDE###3811.00A###2867.00GH###3111.70CDEF###367.10DE###5908.80CDEF###36.50AB###5052.20GH

Koharba###944.00DE###384.60EF###4859.90EFGH###1293.60G###472.00DE###3321.50FGHIJK###32.80BC###3933.40GH

Kokna###856.60DE###209.78F###10768.80CDE###2132.70CDEFG###367.10DE###5821.40CDEFG###37.08A###5769.00FGH

Kozanabad###1503.40BCD###297.19EF###5769.00EFGH###2116.70CDEFG###524.40CDE###2622.20JK###26.60CD###2797.00GH

Makraan###1538.40BCD###576.90EF###9580.00CDEF###3811.00ABC###4527.80A###9422.70A###32.80BC###16555.30A

Neelam###978.90CDE###594.38DEF###14160.30ABC###3496.30BCD###244.70E###3618.70EFGHIJK###25.60CD###3950.80GH

Peela Dora###944.00DE###472.00E###7447.20EFG###3776.00ABC###367.10DE###4090.70DEFGHIJK###25.60CD###15226.60BCD

Peeli Sundar###839.10DE###664.31 DEF###10052.00CDEF###1957. 90DEFG###279.70E###2639.70IJK###25.60CD###2115.30H

Qantar###891.57DE###419.56EF###7342.30EFG###1888.00DEFG###367.10DE###2010.40K###25.60CD###2552.30GH

Rachna###716.70DE###1328.60BC###13461.00BCD###5017.20AB###367.10DE###6101.10CDE###25.60CD###11747.80BCD

Saib###891.57DE###716.75DE###9405.20CDEF###1206.20G###1346.10B###3443.90EFGHIJK###36.50AB###5174.62GHI

Shado###786.60DE###297.19EF###7901.70DEFG###2342.50CDEFG###367.10DE###3146.70GHIJK###36.50AB###6643.10FGH

Shamran###1241.20BCDE###716.75DE###14002.90ABC###2919.40CDEFG###699.20CDE###4160.60DEFGHIJK###32.80BC###10891.10CDEF

Shamran-2###1538.40BCD###576.90EF###5734.00EFGH###1853.00DEFG###367.10DE###3181.60GHIJK###25.60CD###7884.30EFG

Wahan Wali###681.790DE###734.23 DE###4265.50FGH###1433.50FG###576.90CDE###3199.10GHIJK###31.30BC###3985.80GH

Zaidi###1485.90BC###472.00E###18950.30A###5174.60A###786.60CDE###7744.40ABC###26.60CD###15908.40BCD

Zardu###1206.20BCDE###489.49EF###16520.30AB###3234.10CDE###367.10DE###4335.40DEFGHIJK###26.60CD###12272.20BCDE

Zeerin###1241.20BCDE###419.56EF###5489.30EFGH###1905.50DEFG###594.30CDE###2429.90JK###25.60CD###6293.40FGH

Endodermis Cell Area

Makraan showed the greatest endodermis cell area (4527.80m2) whereas Neelam had lowest values (244.70 m2). However significant variation (Pless than 0.01) in endodermis cell area was observed in all the cultivars (Table 2).

Phloem Area

All cultivars varied significantly (Pless than 0.01) in phloem area (Table 2). Makraan (9422.70 m2) had biggest phloem area followed by Zaidi (7744.40 m2) while Qantar had smallest values (2010.40 m2).Pith Area

Significant variation (Pless than 0.01) was observed in pith area in all the cultivars (Table 2). Kokna had maximum pith area (37.08 m2) While Karbalaen showed the minimum pith area (20.93 m2).

Metaxylem Area

Metaxylem area varied significantly (Pless than 0.01) in all the cultivars (Table 2). Metaxylem area was recorded utmost in Makraan (16555.32 m2) while Peeli Sundar had the least values (2115.30 m2).

Discussion

Different date palm cultivars examined during this study showed significant variations in root anatomy. The size of epidermis cells size and shape of outer cortical region presence of sclerification in outer cortex sclerenchyma bundles in cortical region and presence of aerenchyma were quite significantly (Pless than 0.01) variable in these cultivars. Similarly endodermal layer thickness thickness of outer tangential wall of endodermis shape and size of phloem region size and arrangement of metaxylem vessels and sclerification in the pith region showed significant (Pless than 0.01) diversity.Epidermis in Aseel' was comprised of extremely large cells and very well developed sclerenchyma in outer cortical region. Outer cortex was composed of very much reduced parenchymatous cells whereas inner cortex had larger rounded and densely packed cells. Distinctive sclerenchyma bundles were recorded in inner cortex. However well-developed aerenchyma was present just outside the endodermis. Intensive sclerification was also recorded in the vascular region. The variation in parenchymatous cells that is a small tightly packed cells in the outer cortex. Larger cells in the inner cortex with distinctive sclerenchyma region sclerenchyma bundles and aerenchyma may indicate the high tolerance level of this cultivar to variety of environmental condition (Nadia et al.2010). Such structural modifications are critical not only for water conservation particularly under water scarcity but also better moisture storage and even toxic ion compartmentalization (Breckle 2004; Reinoso et al. 2004). Drought decreased the diameter of root metaxylem vessels thus lowering the risk of embolisms and increasing water- flow resistance and increased the number of root hairs (Tomar et al. 2006) but intensive sclerification may also be involved in preventing water loss through the root in addition efficient translocation of oxygen and solute via aerenchyma as Boris and Michael (1997) examined the plant adaptation to anaerobic stress and reported that mechanisms of tolerance of plants can include metabolic adaptations and developmentally passive tolerance such as in over wintering rhizomes of many wetland species.Qantar showed very prominent modification in root anatomy with extremely large aerenchyma in inner cortex and intensive sclerification in outer cortex and vascular region. High proportion of aerenchyma is vital for a variety of environmental stresses. Aerenchyma is known to be a feature of aquatic plants but aerenchyma may be related to high stresstolerance against salinity and drought (Dennis et al. 2000).Structural modifications in the roots of Makraan were large cells in the outer cortex well developed sclerification separating outer and inner cortical region and well developed aerenchyma above the endodermis. Moreover endodermis was extremely thick walled whereas large phloem cells alternating the metaxylem vessels in the vascular region. Intensive sclerification was also recorded in pith region. Thesclerification in roots can minimize the water loss through root in addition to controlling the radial flow of water and nutrients (Michael and Ehwal 2010). Furthermore larger phloem cells and metaxylem vessels are capable of increasing transport of water nutrients and reserve food more efficiently. Most nutrients except calcium are imported through the phloem (Patrick and Offler 2001).Zaidi showed extremely large epidermal cells with enormous sclerification in hypodermal region in addition to large closely packed cells. Structural modifications in cultivar Zaidi can be related to high tolerance against abiotic stress modifications like intensive sclerification (Richard et al. 2011). Thick epidermis with intensive sclerification in the cortical region not only prevents the water loss from the roots but also provides mechanical strength to the root and is extremely important under harsh ecological conditions such as drought (Reinoso et al. 2004; Breckle 2004). All these parameters can play a critical role in moisture conservation and this is extremely useful under drought conditions. Similar structural modifications were also recorded in Neelam. However in the latter case vascular region is extremely enlarged. This may be a crucial for water conservation (Beebe et al. 2008).Berehmi showed typical characteristics in the root anatomy with well-developed sclerification in cortical region large proportion of aerenchyma highly enlarged phloem and large metaxylem vessels. Moreover intensive sclerification was also recorded in the endodermal cell walls. Such modifications can help in transport of solute and reserve food (Beebe et al. 2006) and are helpful in controlling radial flow of water (Beebe et al. 2000). Large phloem area may be responsible for increased translocation of photosynthate but few and large metaxylem vessels may resist efficient transport of water and solute. Large metaxylem vessels step changes in xylem pressure applied to the base of roots (Frensch et al. 1995). During periods of varying water supply roots are optimized in their abilities to use water resources in the soil (Ernst and Peterson 1998). Overall root structure in Berehmi indicated relative sensitivity of cultivar to environmental stresses. This may be the reason of its limited cultivation in Jhang and Faisalabad region.Anatomical features in Zeerin Kozanabad Shamran-2 Karbalaen Peela Dora Shamran and Peeli Sundar were very similar. All these cultivars showed large epidermal cells and distinct sclerenchyma in the cortical region large proportion of aerenchyma in inner cortex thick endodermis and intensive sclerification in vascular region. Epidermis along with intensive sclerification in cortex as well as vascular region is characteristic of drought tolerant plants (Blum 2005). Therefore all these cultivars can be rated as suitable for arid and semi-arid regions (Rao 2002).Highly enlarged vascular region with large metaxylem vessel and large aerenchyma were recorded in cultivars Shado Khudrawi-1 and Khudrawi-2. These cultivars also showed distinctive sclerenchyma in cortical regionprominent sclerenchyma bundles and high proportion of aerenchyma in the cortex. However large metaxylem vessels collapse but at the same time they can involve more and efficient transport of water and nutrients. On these bases it can be concluded that these cultivars can perform better under moderate climate (Hameed et al. 2009).Distinct modification in the root anatomy of Koharba was observed. Large ovoid metaxylem vessels were the characteristic feature in the transverse section. In addition very prominent sclerification was recorded in epidermal and hypodermal region. Both cultivars were characterized by small aerenchyma and highly sclerified pith region. These anatomical features are typical of xeric nature with the main function of efficient transport of water and prevention of water loss through the roots (Ryan 1993).Cultivars Kokna and Saib were characterized by relatively poor development of sclerenchyma both in cortical vascular region and numerous small numerous metaxylem vessels on the basis of low proportion of sclerification. These cultivars can tolerate mild environmental stresses (Steudle 2000). Taxonomically important featureswere the nature of sclerification in the cortical region distinctouter and inner cortex shape number and size of the metaxylem vessel and size and shape of phloem.In conclusion all studied cultivars may have evolved independently from diverse origin during their evolutionary history. The investigation also explored the anatomical characters of roots of date palm. Such study added precise evidence to taxonomic identity of different cultivars of date palm which include group of the most important cultivars.

Acknowledgments

The authors are obliged to the staff at Date Palm ResearchStation Jhang Pakistan and thankful to International Centerfor Development and Decent Work (ICDD; DAAD)Germany for financial support.

References

Baruch Z. and T. Merida 1995. Effects of drought and flooding on root anatomy in four tropical forage grasses. Int. J. Plant Sci. 156: 514521Beebe S.E. P.W. Skroch J. Tohme M.C. Duque F. Pedraza and J.Nienhuis 2000 Structure of genetic diversity among common beanlandraces of Mesoamerican origin based on CorrespondenceAnalysis of RAPD. Crop Sci. 40: 264273Beebe S.E. M. Rojas X. Yan M.W. Blair F. Pedraza F. MuAoz J.Tohme and J.P. Lynch 2006. Quantitative trait loci for rootarchitecture traits correlated with phosphorus acquisition in CommonBean. Crop Sci. 46: 413423Beebe S.E. I.M. Rao C. Cajiao and M. Grajales 2008. Selection fordrought resistance in common bean also improves yield inphosphorus limited and favourable environments. Crop Sci. 48:582592Blum A 2005. Drought resistance water use efficiency and yield potential. Aust. J. Agric. Res. 56: 11591168Boris B.V. and M.B. Michael 1997. Plant adaptations to anaerobic stress.Ann. J. Bot. 79: 320Breckle S.W. 2004. Flora vegetation und Alkologie der alpin-nivalen Stufe des Hindukusch (Afghanistan). In: Results of worldwide ecological studies. Proceed: 2nd Symposium A.F.W. Breckle S.W. B. Schweizer and A. Fangmeier (eds.). pp: 97117. Schimper- Foundation Stuttgart-Hohenheim GermanyClarkson D.T. and A.W Robards 1975. The endodermis its structural development and physiological role in the development and function of roots. Academic Press London. pp: 415436Dennis E.S. R. Dolferus M. Ellis M. Rahman Y. Wu F.U. Hoeren A.Grover K.P. Ismond A.G. Good and W.J. Peacock 2000. Molecular strategies for improving waterlogging tolerance in plants.J. Exp. Bot. 342: 8997El-Shibli S. and H. Korelainen 2009. Biodiversity of date palm (Phoenixdactylifera L.) in Sudan: Chemical morphological and DNApolymorphism of selected cultivars. Plant Genet. Resour. 7:194203Ernst S. and C.A. Peterson 1998. How does water get through roots J.Exp. Bot. 49: 775788FAO 2011. Date Palm Cultivation. FAO plant production and protectionpaper. Food and Agriculture Organization of the United Nation.Rome ItalyFrensch J. T.C. Hsiao and E. Steudle 1995. Water and solute transportalong developing maize roots. Planta 198: 348355Hameed M. M. Ashraf and N. Naz 2009. Anatomical adaptations tosalinity in cogon grass [Imperata cylindrica (L.) Raeuschel] fromthe Salt Range Pakistan. Plant Soil 322: 229238Jamil M.S. R. Nadeem M.A. Hanif M.A. Ali K. Akhtar 2010. Proximatecomposition and mineral profile of eight different unstudied date(Phoenix dactylifera L.) varieties from Pakistan. Afr. J. Biotechnol.9: 32523259Markhand G.S. A.A. Abul-Soad A.A. Mirbahar N.A. Kanhar 2010. Fruitcharacterization of Pakistani Dates. Pak. J. Bot. 42: 37153722Michael F. and R. Ehwal 2010. Mannitol permeation and radial flow ofwater in maize roots. New Phytol. 189: 210217Nadia A. A. Kikuchi and K.N. Watanabe 2010. Assessment of somaclonal variation for salinity tolerance in sweet potato regenerated plants.Afr. J. Biotechnol. 9: 72567265Ogburn R.M. and E.J. Edward 2009. Anatomical variation in Cactaceaeand relatives: trait liability and evolutionary innovation. Amer. J.Bot. 96: 391408Patakas A. 2012. Abiotic Stress-Induced Morphological and AnatomicalChanges in Plants. Biomedical and Life Sciences. Abiotic StressResponses in Plants. pp: 2139 Springer New York USAPatrick J.W. C.E. Offler 2001. Compartmentation of transport and transferevents in developing seeds. J. Exp. Bot. 52: 551564Rao I.M. 2002. Role of physiology in improving crop adaptation to abioticstresses in the tropics: the case of common bean and tropical forages.In: Handbook of Plant and Crop Physiology. 3edition pp: 583613. Marcel Dekker Inc. New York USAReinoso H. L. Sosa L. Ramirez and V. Luna 2004. Salt-induced changes in the vegetative anatomy of Prosopis strombulifera (Fabaceae). Can. J. Bot. 82: 618628Richard L.T. A. Ergul R.L. Albion K.A. Schlauch G.R. Cramer and J.C.Cushman 2011. Identification of tissue-specific abiotic stress-responsive gene expression patterns in wine grape (Vitis vinifera L.)based on curation and mining of large-scale EST data sets. PlantBiol. 11: 86Ruzin S.E. 1999. Plant microtechnique and microscopy. pp: 322. OxfordUniversity Press Oxford UKRyan P.R. J.M. Ditomaso and L.V. Kochian 1993. Aluminum toxicity inroots: an investigation of spatial sensitivity and the role of the rootcap. J. Exp. Bot. 44: 437446Seago J.L. and L.C. Marsh 1989. Adventitious root development in Typhaglauca with emphasis on the cortex. Amer. J. Bot. 76: 895909Steudle E. 2000. Water uptake by roots: effects of water deficit. J. Exp.Bot. 51: 15311542Tomar R.K. D. Singh K.S. Gangwar R.N. Garg V.K. Gupta R.N. SahooD. Chakraborty and N. Kalra 2006. Influence of tillage systems andmoisture regimes on soil physical environment growth andproductivity of rice-wheat system in upper Gangetic plains ofWestern Uttar Pradesh. Ind. J. Crop Sci. 1: 146150Zimmerman H.M. and E. Steudle 1998. Apoplastic transport across youngmaize root: effect of the exodermis. Planta 206: 719
COPYRIGHT 2014 Asianet-Pakistan
No portion of this article can be reproduced without the express written permission from the copyright holder.
Copyright 2014 Gale, Cengage Learning. All rights reserved.

Article Details
Printer friendly Cite/link Email Feedback
Author:Fatima, Ghayoor; Khan, Iqrar Ahmad; Jaskani, Muhammad Jaffar; Khanum, Fakhara
Publication:International Journal of Agriculture and Biology
Article Type:Report
Geographic Code:9PAKI
Date:Aug 31, 2014
Words:4239
Previous Article:Effects of drought stress and sward botanical composition on the nutritive value of grassland herbage.
Next Article:Assessment of genetic diversity in fenugreek (Trigonella foenum- graecum) in Oman.
Topics:

Terms of use | Privacy policy | Copyright © 2021 Farlex, Inc. | Feedback | For webmasters |