quasi in situ conservation

7/30/2019 quasi in situ conservation

1/24

Complexex situ - in situ approach or conservation o endangered plant species... 137

Complex ex situ - in situ approach for conservation ofendangered plant species and its application to

Iris atrofusca of the Northern Negev

Sergei Volis1, Michael Blecher2, Yuval Sapir3

1 Lie Sciences Department, Ben Gurion University o the Negev, Israel2 Ein Gedi Nature Reserve, Israel Na-

ture and Parks Authority, Israel3 Porter School or Environmental Studies and Department o Plant Sciences,

Tel Aviv University, Israel

Corresponding author: Sergei Volis([email protected])

Academic editors:L.J. Musselman, F. Krupp | Received 4 February 2009 | Accepted 14 December 2009 | Published 28 December 2009

Citation: Volis S, Blecher M, Sapir Y (2009) Complexex situ - in situ approach or conservation o endangered plant

species and its application to Iris atrouscao the Northern Negev. In: Krupp F, Musselman LJ, Kotb MMA, Weidig I (Eds)

Environment, Biodiversity and Conservation in the Middle East. Proceedings o the First Middle Eastern Biodiversity

Congress, Aqaba, Jordan, 2023 October 2008. BioRisk 3: 137160.doi: 10.3897/biorisk.3.5

Abstract

We introduce a novel approach or conservation o endangered plant species in which ex situ collections

maintained in natural or semi-natural environment are a part o a complementary ex situ in situ con-

servation strategy. We provide detailed guidelines or 1) representative sampling o the populations; 2)

collection maintenance; and 3) utilization or in situ actions.Our approach is the frst that explicitly takesinto account ecologically signifcant (i.e. adaptive) variation o plants in both ex situ and in situ conserva-

tion actions. We propose that an important part o the conservation strategy is preserving both neutral

and adaptive genetic diversity through a quasi in situ conservation approach. Finally, we demonstrate this

approach using a critically endangered plant species, Iris atrouscarom the northern Negev, Israel.

Keywords

In situ, ex situ, conservation strategy, relocation, translocation, local adaptation

Introduction

A large body o theoretical and empirical work has been devoted to particular questions

about optimal conservation, such as the importance o inbreeding depression (Hedrickand Kalinowski 2000, Keller and Waller 2002), population size (Barrett and Kohn

BioRisk 3: 137160 (2009)

doi: 10.3897/biorisk.3.5

www.pensoftonline.net/biorisk

Copyright S. Volis, M. Blecher, Y. Sapir. This is an open access article distributed under the terms of the Creative Commons Attribution License,

which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

RESEARCH ARTICLE

Biodiversity & Ecosystem Risk Assessment

A peer-reviewed open-access journal
http://dx.doi.org/10.3897/biorisk.3.5mailto:[email protected]:[email protected]://dx.doi.org/10.3897/biorisk.3.5http://dx.doi.org/10.3897/biorisk.3.5http://dx.doi.org/10.3897/biorisk.3.5http://www.pensoftonline.net/bioriskhttp://creativecommons.org/licenses/by/3.0/http://dx.doi.org/10.3897/biorisk.3.5http://creativecommons.org/licenses/by/3.0/mailto:[email protected]://www.pensoftonline.net/bioriskhttp://dx.doi.org/10.3897/biorisk.3.5


2/24

Sergei Volis, Michael Blecher & Yuval Sapir / BioRisk 3: 137160 (2009)138

1991, Ellstrand and Elam 1993), isolation (Newman and allmon 2001), genetic di-versity (Lande and Barrowclough 1987; Newman and Pilson 1997) and outbreedingdepression (Huord and Mazer 2003, allmon et al. 2004). But, to-date there werelimited attempts to conceptually unite dierent aspects o population viability as part

o a conservation methodology. Such unifcation is especially lacking or ex situ conser-vation. In this paper we review the state-o-art in ex situ conservation with an emphasison its utilization within a more general strategy having a fnal in situ output. Ten weintroduce a detailed approach or conservation o endangered species that integratesex situ and in situ conservation as complementary and that could be used as a tool orfnding an e cient solution to a particular conservation task. Finally, we present astudy where this approach is applied or an endangered plant species.

Ex situconservation

Ex situ conservation methods samples genetic diversity o species using certain criteriaand store/propagate the collected material outside the natural environments in whichthe species grows (Heywood and Iriondo 2003). Importance oex situ collections orconservation in situ was realized when collections in botanical gardens and arboretahelped implementation o population management and recreation (Falk 1987; Given1987; Millar and Libby 1991). At the same time, limitations o their useulness be-came evident. Te latter include poor genetic or demographic management almostinevitably resulting in genetic erosion, artifcial selection and spontaneous hybridiza-tion. o prevent/reduce negative eects o genetic drit, inbreeding depression andmutational meltdown, that all happen as a result o small (eective) population size oa collection, sampled individuals must be maintained separately or through controlledbreeding and pedigree design. Tis introduces other limitations oex situ collections,such as space limitations and high cost o maintenance.

A need o a conceptually sound link between conservation-oriented ecologicaland genetic research, and its routine application to ex situ management has been

recognized (Maunder et al. 2004a). Ex situ conservation needs biologically eective,fnancially realistic and easy-to-use guidelines that can be applied to a wide range osituations. Te development o such guidelines must take into consideration basicissues o conservation biology. raditionally, the germplasm sampled or ex situ col-lection is supposed to represent potential adaptive variation within a species (Brownand Briggs 1991, Brown and Marshall 1995, von Bothmer and Selberg 1995). Incase o limited resources or collecting and maintaining plants, minimal samplingcan precede additional sampling, which will be perormed upon availability o moreresources (Brown and Briggs 1991). Te key issue is choosing a limited, but repre-

sentative, number o populations, using the correct criterion. Tis criterion, in ourview, should be ecologically signifcant (i.e. not the potentially adaptive, but the cur-rently adaptive) variation. Tereore, research that allows detection o spatial patterno morphological, lie history and ftness traits, should be the frst priority tool or


3/24


providing sampling guidelines (Husband and Campbell 2004). Although variationrevealed with molecular markers can provide valuable insights into the importanceo dierent non-selective processes in species evolution, this inormation is secondaryor making conservation decisions.

An endangered species is usually represented by small and isolated populations thatalready underwent strong eects o genetic drit and/or inbreeding, i.e. comprise a lim-ited number o genetically dierent individuals (Aguilar et al. 2008). Open pollinationin a sample rom such a population may result in inbreeding depression due to highprobability o mating between genetically identical or closely related genotypes. Onthe other hand, interbreeding o individuals rom environmentally dissimilar habitatsplanted in close proximity oten leads to outbreeding depression. Tese two risks rarelyapply to obligate or predominant selers, but can be extremely important or outcross-ing, and especially or sel-incompatible species. Outbreeding depression is an opposite,as compared with benefcial gene ow between genetically dierentiated (isolated) pop-ulations, hybridization process. Te parents do not necessarily have to be taxonomicallydistinct, viz. be recognized as dierent subspecies. Tereore, or an endangered spe-cies, creation oex situ collections and decisions about suitable material or relocation/reintroduction should take into account the potential risks o inbreeding/outbreedingdepression, in addition to local adaptation and spatial structuring o adaptive variation.

Te above issues should be considered as the basic principles in developing an exsitu conservation approach that would be an integral part o a more general strategy

with an ultimate fnal in situ output. Several approaches combining ex- and in situconservation were proposed in the past, but none is satisying as a general conservationstrategy. For instance, the inter-situ approach proposes an o-site collection maintained

within the natural habitat. Tis approach was considered potentially promising, butwas not tested and no detailed methodology or practical use was developed (Husbandand Campbell 2004). A slightly dierent approach are the orest gene banks (UmaShaanker and Ganeshaiah 1997, Uma Shaanker et al. 2001, 2002). In this concept, aparticular existing population acts as an in situ sink, into which genetic material romseveral source sites is introduced and maintained. Tus the genetically diverse sink

population serves as a repository o the species gene pool and at the same time allowsor random interbreeding. Tis approach might be useul in certain cases (lack o localadaptation, low genetic diversity, sel-incompatability), but may lead to outbreedingdepression when locally adapted genotypes are brought together. Tereore this con-cept cannot be used in a general application.

Quasi in situ conservation

Here, we propose the use oex situ collections in natural or semi-natural environmentsas a part o a complexex situ in situ conservation strategy. Here below we providedetailed guidelines or 1) representative sampling; 2) collection maintenance; and 3)utilization or in situ conservation actions. Te novelty o our approach is in that it ex-


4/24


plicitly takes into account potential local adaptation o plants in both ex situ and in situconservation actions. An integral part o this strategy is preserving the species geneticdiversity (both neutral and adaptive) through quasi in situ conservation.

Te proposed strategy starts with an analysis o the species distribution to identiy

potential locally adapted populations or population groups. Tis analysis is crucial orunderstanding the extent o local adaptation and its spatial pattern. As intensity o lo-cal selection varies, either gradually with increase in distance or abruptly with changein a habitat, only knowledge o the local selection regimes can tell us whether materialis adapted or not. wo main procedures exist to identiy local adaptation: transplanta-tion experiments (e.g. Joshi et al. 2001, Volis et al. 2002), and tests or outbreedingdepression, when a locally adapted genotype is crossed with plants originating romelsewhere (Huord and Mazer 2003). I local adaptation is important, the introducedgenotypes must ft into the local biotic and abiotic conditions, i.e., it should comerom within the area defned as that o intensive local selection, or rom a habitat withclosely similar local selection eects.

Experimental determination o a scale o local adaptation (Fig. 1) is a highly desiredsecond step o the procedure. A potential or local adaptation and its spatial scale can beroughly predicted rom knowledge o a species breeding structure and lie history. Sel-pollination and short seed or pollen dispersal distance are known to be associated witha smaller scale o local adaptation than outcrossing and long-distance seed or pollendispersal (Linhart and Grant 1996). However, these considerations are too general to

Figure 1. A scheme o relationship between (i) species properties (breeding structure, lie history) and (ii)

scale o local adaptation, and implications o (i) and (ii) or sampling and introduction. Te scheme shows

that predominant outcrossing and large dispersal distance are associated with large scale local adaptation,

necessitating increased size, genetic diversity and connectivity o introduced populations.

inbreedingsampling introduction

Populationsize

Represen

tativefor

therange

ofadapted

ecotypes

Geneticdiversity

Connectivity

seed/pollendispersaldistance

outcrossing

Observations,experiments

Experiments Experiments,modelling

Small-scale adaptation, discrete pattern

Large-scale adaptation, discrete pattern

Small-scale adaptation, clinal pattern

Small-scale adaptation, clinal pattern

Breeding, life history Scale of local adaptation Conservation implications


5/24


be used as guidelines or conservation o a particular species because o numerous otheractors, such as patterns o environmental variation (e.g. discrete or clinal), numbero available habitats, a species evolutionary potential, time since the last colonization,etc. Tereore, an experimental assessment o the scale o local adaptation is crucial.

Such a test should include all habitats where the species is ound (discrete variation)or locations along an environmental gradient (clinal variation). O course, logisticalconsiderations may limit a range o habitats or locations to be tested, or prevent testingor local adaptation at all. In this case variability in morphology, phenology and lie his-tory traits across a species range must be known. Tis variability matching importantenvironmental parameters (e.g. temperature, soil type, rainall) or being associated withdistinct habitats or vegetation communities are indications o local adaptation.

I phenotypic or genetic variation is spatially structured, even though it is not aresult o natural selection, it may represent distinct evolutionary lineages within spe-cies, being an important part o the species diversity. Tis variation, although neutral,is important or preserving species evolutionary potential, i.e. ability to adapt to utureclimate or habitat changes. As neutral genetic variation in many cases is not reectedin phenotypic or in molecular markers variation, its existence must be presumed whena species consists o populations not connected through gene ow.

With knowledge about spatially structured adaptive and neutral variation, a samplingdesign is worked out. Te optimal design or ex situ collection is a stratifed one, with alower level (o neutral variation) nested within a higher one (o adaptive variation). Prac-tically, this means that or a species present in several habitats (e.g. soil types, regions odierent aridity, vegetation communities), sampling in each habitat must include severalgeographically isolated populations. A representative number o spatially separated indi-viduals must be collected in each population, to ensure sampling o dierent genotypes.

Te next step is planting the germplasm sampled as living collection. In the quasiin situ approach, a choice o a site must take into account local adaptation (testedor presumed). Tis means that there must be a close environmental match o ex situlocation with locations o sampled natural populations. A close match can be biologi-cally meaningul only i the ex situ location is in a natural (or at least semi-natural)

environment. In addition, this site should be protected by national law and practically(regularly) inspected by rangers. In our view, dierent classes o strictly protected ter-ritories are the areas that ully satisy these requirements. An optimal design wouldbe planting several populations representing a particular eco-geographical region orhabitat in a protected area in the same eco-geographical region or habitat. A repre-sentative number o genetically dierent individuals per population should be plantedseparately at distances, allowing subsequent identifcation o planted genotypes. Tisis important or both estimating rate o survival and enabling controlled pollination, inecessary. Following the recommendations o the Center or Plant Conservation in the

United States (Maunder et al. 2004a), number o plants per population should be 10to 50, and fve populations per habitat or eco-region should be sampled.

A comparison between quasi in situ and traditional ex situ conservation in botani-cal gardens is summarized in able 1. We argue that the quasi in situ approach provides


6/24


better representation o genetic diversity, increases chances o germplasm survival, andbetter suits the purpose o propagating material or in situ conservation actions.

In situ conservation aims at either enhancement o existing populations or crea-tion o sel-supported new populations via reintroductions and translocations, using

sampled or propagated material (reviewed in Bottin et al. 2007, Menges 2008). Whena natural population exists, or existed in the recent past, a choice o material is quitestraightorward. A large population rom the same or the geographically closest popu-lation within the same habitat would be the best choice. I, however, relocation isplanned, viz. introduction o material into locations where a population never existed,a decision is more problematic. Tere are many examples o unsuccessul relocationinto sites that seemed highly suitable and were located in close proximity to a location

where natural populations had been extirpated (e.g. Holland 1980, Morton 1982,Cranston and Valentine 1983). Tis implies that the recommendation by Schaal andLeverich (2004) to use or relocation a large sample rom the closest population repre-senting the same habitat, should be treated with caution and only applied when dataon a species environmental requirements are very limited. A much better option is alimited relocation within an experimental ramework, and a ull relocation in thosesites where survival and reproduction are high.

As soon as the relocation sites are chosen, material or propagation may be takenrom natural or ex situ collections. Te major issues are required origin, genetic diversityand quantity. Acquiring su cient quantity o propagation material (seeds, bulbs, rootcuttings, saplings) rom the closest natural population can negatively aect the lattersgrowth rate and threaten its viability. In addition, single source material may lead toinbreeding depression and high susceptibility to diseases. Quasi in situ collection mayeectively solve both problems. Plants, grown in the collection, are (presumably) lo-cally adapted and genetically dierent as they originate rom several populations. Ad-ditionally, naturally occurring cross-pollination o plants in a collection should neitherlead to breakdown o co-adapted gene complexes, nor to dilution o local adaptationbecause all plants in the collection originated rom the same environment and nomaladapted genes will participate in recombination and segregation. Tereore, the

ospring o cross-pollination in a collection should well suit the relocation purpose,and can be collected in large quantities to meet the needs or successul relocation.Te last step in the quasi in situ strategy is determination o spatial parameters o

introduced populations (size, distance rom the nearest population) and monitoring orelocation success. Again, as with choosing a relocation site, experimentation should

Table 1. A comparison between quasi in situ and ex situ conservation.

Parameter Ex situ Quasi in situ

Space or maintaining the collection Limited Less limitedSuitability o environment Usually un-suitable Suitable

Maintenance and renewal o material Artifcial Natural

Cost High Very low and only at the initial stage


7/24


be a common practice when several populations o dierent size are planted and moni-tored over a number o years.

Application: Iris atrofuscao the northern Negev as a case study

Iris atrouscaBaker (Fig. 2) belongs to the section Oncocyclus(Siems.) Baker (Iridaceae)that are characterized by dense clonal growth and conspicuous large, mostly dark ow-ers that grow individually on a stem (Avishai and Zohary 1980, Sapir et al. 2002).Eight species oOncocyclusthat grow in Israel (Feinbrun-Dothan 1986, Danin 2004)have high conservation priority (Sapir et al. 2003) and are included in the Red DataBook o the country (Shmida and Pollak 2007). Iris atrouscais one o the most threat-ened species oOncocyclusirises in Israel these days (Shmida and Pollak 2007).

Iris atrousca is relatively widely distributed. It occurs rom the northern Negevin the south to the Golan heights in the north. Tis distribution is the widest o allOncocyclusspecies in Israel. Identifcation is not always easy. Sapir et al. (2002) showedthat morphologically it does not dier rom its closest relatives, I. hayneiand I. petrana.Morphological traits are also associated with the aridity gradient (Araeh et al. 2002, Sa-pir et al. 2002). However, morphological and genetic analyses indicated that I. atrousca

Figure 2. Lea ans, owers and rhizomes oIris atrouscarom the Goral Hills, northern Negev (water-

color by Irene Blecher 2006).


8/24


populations o the northern Negev orm a cluster within the general pattern (Araeh etal. 2002, Sapir et al. 2002), and might even represent a separate taxon (Kushnir 1949).

Te habitats oI. atrouscain the northern Negev are the most vulnerable through-out its distribution. In the last decade, I.atrouscapopulations o the northern Negev

have been suering mainly rom anthropogenic disturbance that decreased populationsizes, with some populations becoming extinct. Tese disturbances include urbaniza-tion, inrastructure works, intensive and extensive agriculture, overgrazing, orestry

works, and illegal Bedouin settlements. Recently, a plan or expanding the area o BeerSheva, the main town o the northern Negev, is threatening the largest and the densestpopulations oI. atrousca, which grow in Goral Hills, north o the town. Tese issueslead to urgent research oI. atrouscapopulations in the Negev. Here we present studies

we did under the guidelines we drew above or the quasi in situ conservation approach.

Methods

Research area

Iris atrouscagrows in the northern Negev in two main groups o populations: in GoralHills (central coordinates: 3118'N 3448'E), north to Beer Sheva, and Arad Valley(central coordinates: 3116'N 3507'E) (Shimshi 1979/8).

Te two regions dier in climate. While the Goral Hills area is above the 200 mmisohyet (semi-arid conditions), the Arad Valley is close or below to the 150 mm iso-hyet, which indicates arid conditions (Atlas o Israel 1985, Jae 1988).

Te topography o the Goral Hills area is mostly slopes o shallow hills. Te angleso the slopes are up to 20%. Te soil is a shallow calcareous lithosol overlying rac-tured Eocene limestone (Shimshi 1979/80). Depressions between the hills are flled

with shallow loessial soil. Arad Valley, on the other hand, is a relatively at plain (withwadis and gullies), covered with Quaternary aeolian loess o considerable thickness(> 2 m), with some isolated outcrops o calcareous lithosols (Shimshi 1979/80), which

are mostly the heads o insulated hills.In hard and fssured limestone and dolomite with calcareous lithosol some o therain water penetrates the soil and is accumulated in the fssures and crevices, where it isprotected rom direct evaporation. Loessial soils have a dierent moisture regime. Dueto the high moisture holding capacity o the fne-grained substratum, some o therain

water is absorbed by the upper soil layers, but most o this water is consequently lostby direct evaporation rom the soil surace (Danin 1988).

Inventory and demographic observations

A feld survey based on previous knowledge on the distribution o the species in thenorthern Negev was conducted in 2006. Te survey aimed at documenting the pre-


9/24

Complexex situ - in situ approach for conservation of endangered plant species... 145

cise locations o populations, the distributing area o each population, and to recordecological conditions and anthropogenic impacts. In each population, clumps oIrisatrofuscawere recorded or their size, estimated by the diameter o the clump.

To assess population growth rates, we started, in 2006, a detailed census o two

populations representative o two regions, the Goral Hills and Arad Valley (GvaotGoral, G-G, and Tel Arad, T-A, respectively) (Fig. 3). Two permanent observationplots were established: 120 m x 6 m (G-G) and 60 m x 6 m (T-A), respectively).In March 2006 we counted all individuals within the plots and classiied themas either immatures (1st or 2nd year juveniles with a single an), vegetative (non-lowering, but with > 1 an) adults or reproductive adults (Fig. 4). We markedeach established clump (=genet) oI. atrofuscaindividually, measured its diameterand counted the number o lea-ans (=ramets). Also in April 2007 and 2008, werecorded number, size, and reproductive status o adults in the plots. Each season(2006, 2007 and 2008) we calculated the average number o ruits per repro-ducing plant (i.e. a clump comprising >1 ramets), average number o seeds perruit, and resulting ecundity. Measurements and counting were done when plantsstarted to senesce.

Since the actual age o individual plants oI. atrofuscain the feld can not be de-termined, the population structure analysis was based on the number o individuals

Figure 3. Map o populations surveyed, experimental relocation sites and populations in which perma-

nent demographic observations plots were established.


10/24


in the dierent ontogenetic stages o the lie cycle. During the years 2005 to 2008 weollowed the germinated seeds to distinguish age-stages in I. atrousca. We identifedthe ollowing age-stage categories (Fig. 4):1. Seeds;2. Seedlings (individuals developed shortly ater germination o seeds, with cotyle-

dons and oten with one pair o leaves);3. Juveniles (individuals with a single lea an comprising more than two leaves and

having a poorly developed root system); a major dierence between 1-year and2-year juveniles is in the development o the root system, where the latter starts todevelop a rhizome;

4. Vegetative adults or immatures (non-owering individuals with more than two leaans and ully developed root system, which has a developed rhizome);

5. Generative adults (individuals bearing owers).

Oncocyclusplants are dormant between the end o the owering season (end ospring) and the start o the next winter. Our observations indicate that plants can stay

dormant during not only summer, but also during the next growing season, rom allto spring (Volis & Blecher, pers. obs.). Tis adds another ontogenetic stage or adults dormants, which will be verifed as more demographic data become available.

Figure 4. Plants oI. atrouscaollowed rom seed germination on and representing dierent age-stages

(seed, seedling, juvenile and vegetative adult).

seed

seedling 1-year juvenile 2-year juvenile 3-year juvenile


11/24


Adult plants can be distinguished rom juveniles in the feld by the compact assem-blage o lea ans, which emerge close to each other rom the below-ground rhizome(Fig. 4). All these lea ans are genetically identical individuals (ramets) that may be-come independent plants ater ragmentation o the mother rhizome (genet).

Plant sizes and number o ans per clump were log-transormed and analyzed acrossyears and habitats using repeated-measures ANOVA. Only alive and non-dormantadults were analyzed or these two traits.

Soil seed-bank and germination trials

We created three experimental permanent soil seed banks and started monitoring theate o the seeds in all 2005 at el Arad National Park (Fig. 3). Seeds o I. atrousca

were collected by MB rom plants in proximity to the plots under observation in 2005.Te seeds were buried at three sites along the slope in: (1) plastic trays flled with soilo the site o transplanting and containing one spikelet per cell (221 seeds per tray, onetray per site), placed about 2 cm below ground level, and (2) in urrows (100 seeds perurrow, two urrows per site).

Similar soil seed banks were established in all 2006 at Gvaot Goral site (Fig. 3).wo trays, each containing 221 locally collected seeds, were buried at the top and thebottom o the hill. Te experimental soil seed banks were monitored or seed germina-tion during 2006 to 2008.

Efect o rhizome initial size on growth and owering

Tis experiment was conducted during the growing seasons o 2005 and 2006. Weused only rhizomes with one distinct bud to test the eect o initial rhizome weighton probability o owering. We also measured several morphological traits to iden-tiy potential morphological indicators or probability o owering. Rhizomes were

planted in 3-liter pots flled with loess soil, one weighted rhizome per pot. Pots wereplaced 25 cm apart in a nethouse, and watered regularly with 2-liter/hour drippers,one dripper in each pot. During the experiment (November April) plants were get-ting natural rainall (208 mm) plus supplementary watering (equivalent to 95 mm orainall), to compensate or the higher evaporation rates rom the pots. At frst sign oleaves senescence the ollowing measures were taken: length and width o the longestlea, diameter at the base o the lea an, number o ramets, and number o owers.

Ater complete drying out o above-ground biomass the rhizomes were dug out andweighted. Te sample size was 204 plants. Large rhizomes rescued by MB in 2005

rom the Goral Hills (road-building strip or new railroad tracks) that represented agroup o (potentially) independent ramets were cut into pieces and used in this andthe ollowing experiments.


12/24


Creation o quasi in situ gene banks

Between 20 to 50 large genets o I. atrousca, comprising many ramets, were sam-pled rom our populations rom Goral Hills and Arad Valley regions. Populations

were chosen based on: (1) the threat o habitat destruction the populations chosenwere critically endangered (construction, agriculture, etc.) and required immediaterelocation; and (2) their representation or the distributional range oI. atrouscainthe northern Negev. Te plants were planted in two replicates at both el Beer Shevaand el Arad National Parks (Fig. 3) that represent ecological conditions like those oGoral Hills and Arad Valley areas, respectively. However, as the two population groups(Goral and Arad areas) were ound to dier in habitat, demography and morphology(Shimshi 1979/80; Blecher 2007 and this study), we decided that el Beer Sheva andel Arad National Parks will harbor populations rom their respective regions only,and the populations planted outside their region o origin will be relocated to the re-uge in their respective region at the next stage o the project. Meanwhile, we are moni-toring the transplanting success o plants o dierent origin across the two regions.

Relocation experiments

Rapid disappearance o I. atrousca populations in the Negev necessitates measureso species conservation, such as relocation to sae areas, protected by law. In orderto determine species habitat preerences we set relocation experiments at two scales,large (tens o kilometers) and small (hundreds o meters), respectively, using rhizomesrescued rom sites o habitat destruction and immediate threat or the plants, i.e. rompopulations that required relocation.

Large scale relocation experiment

wo sets o fve large (> 20 g) and 15 small (510 g) rhizomes o I. atrouscaoArad Valley and Goral Hills origin were planted in six locations that embracedthe whole species range in the Negev and beyond it. Te locations were: KKLexperimental site near Oakim, el Beer Sheva National Park, Nevatim Basis, La-hav North Nature Reserve, el Arad National Park, Har Amasa Nature Reserve(Fig. 3). In spring 2007 and 2008 we recorded the numbers o surviving plants,owers and ruits per plant.

Small scale relocation experiment

Rhizomes rescued in spring 2006 in the Goral Hills area (construction o new railroadtracks) were planted in all 2006 in sets o 62 rhizomes at 22 microhabitats in Lahav


13/24


North Reserve (Fig. 3, 9). Each set comprised the ollowing size classes: 40 g (2). In spring 2007and 2008 we recorded the numbers o surviving plants, owers and ruits per plant.

Results

Distribution and habitats

Te results o this survey (able 2) clearly show that in the Arad Valley about a thirdo the plants oI. atrouscagrow in wadis. In the Goral Hills area, no population wasound in wadis. Detailed geographical interpretation o data on I. atrouscasurvey inthe northern Negev, including categorization o the populations or protection pur-poses, is presented in Blecher (2007) with proposals or new protected areas and en-largement o the existent Parks.

Te two populations studied (Gvaot Goral and el Arad) diered in average plantdensity, estimated in spring 2006 (0.88 vs. 0.30 plants/m2 in G-G and -A, respective-ly). Tere was a marginally signifcant dierence between two populations in clumpsize, with clumps at G-G being consistently larger during three years than at -A. Tenumber o ramets per genet exhibited signifcant season/population interaction. Tistrait was more constant over the years at G-G than at -A (able 3).

Te two populations diered in the stage structure, with juveniles comprising86%, 70% and 46% vs. 23%, 24% and 20% o established plants (over three years)in G-G and -A populations, respectively (able 4). Percentage o owering adultsand average ruit-set per reproducing plant over three years were higher in G-G thanin -A population (4013% vs. 6710% and 1.610.38% vs. 0.520.30%, respec-tively). Te two populations also dramatically diered in ecundity (able 4).

Germination

Low germination rates were observed in the soil seed banks established in 2005 at elArad National Park. During three seasons, 20056, 20067 and 20078, no germina-tion event was recorded in any o the buried trays with seeds. In urrows, no germina-tion was observed in 20056 and 20067, but in 20078 germination raction was

Table 2. Number o plants and distribution oIris atrouscain two geographic regions.

Total distributing area(Hectare)

Total cover oplants* (m2)

Total numbero clumps

Hills and slopes Wadis

Goral Hills 19.3 186 1968 1968 0

Arad Valley 34.8 439 4716 2931 1785

* otal cover o plants is a summary o all clumps.


14/24


4%, 15% and 12% (hill top, middle and oot, respectively) In the Gvaot Goral site,where 2 trays (experimental soil seed banks) were buried in all 2006, one seed germi-nated in the ollowing winter (season 20072008). Tese results suggest strong seedinnate dormancy in the frst year ater dispersal with increase in germination raction

in ollowing years.

Table 4. Lie table or two populations oI. atrouscaduring the seasons 20056, 20067 and 20078.Te table does not account or soil seed bank present at the start o observations. Numbers are or the

whole plot.

Population/stage Season

20056 20067 20078

Gvaot Goral (G-G)Seeds 3238 2318

Juveniles 357 142 90

Non-reproducing adults 17 16 70

Reproducing adults 43 46 35

Fecundity (seeds/repr. plant) 75.3 50.4 16.4

el Arad (-A)

Seeds 592 199

Juveniles 25 23 22

Non-reproducing adults 66 33 67Reproducing adults 19 38 19

Fecundity (seeds/repr. plant) 31.2 5.25 8.4

= not estimated

Table 3. Repeated measures ANOVA o the eects o population and season on clump size and number

o ramets per genet (top) and means S.E or each season (bottom). G-G Gvaot Goral population,

-A el Arad population.

Source o variation DF F F

Clump size Ramets per genet

Population 1 2.91 2.38 ns

Error 109

Season 2 0.59 ns 1.82 ns

Season * Population 2 0.91 ns 6.15**

Error 218

Season Clump size (cm) Ramets per genet

G-G -A G-G -A

20056 24.02.6 19.82.4 21.53.3 18.63.2

20067 23.12.6 19.82.5 18.32.5 15.02.5

20078 25.12.5 22.62.8 18.02.3 21.82.8

** p < 0.01; p < 0.10; ns not signifcant.


15/24


Efect o rhizome initial size on growth and owering

Te results o this experiment (able 5) clearly show that sexual reproduction (i.e.,production o a ower) in I. atrouscadepends on the rhizome weight and two size-re-

lated parameters, namely length o the leaves and base diameter. Te minimal rhizomeweight or owering appears to be around 2.7 g-3.0 g, but probability o owering orsuch plants is less than 10% (Fig. 5). Te optimal rhizome weight with reasonably highprobability o owering (around 50%) is above 4 g (Fig. 5).

Creation oquasi in situliving collections

wo years ater planting, survival rates in two living collections were equally high,approximating 100%. Percent o owering plants was substantially higher in el Beer

Table 5. Results o multiple logistic regression testing eect o fve predictor variables on probability o

owering.

Parameter Wald Statistics p

Intercept 0.24 0.6210

Rhizome weight 30.76 < 0.0001

Lea length 13.46 0.0002

Lea width 0.15 0.7008Base diameter 4.20 0.0403

Number o lea-ans 1.26 0.2618

Figure 5. Proportion o plants owering and total number o plants o dierent rhizome weight classes

in the experiment described in the text.

Number of plants in experiments

40

35

30

25

20

15

10

5

0 0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

0 1 2 3 4 5 6 7 8 9 10 11 12 >12

Prportion of plants flowered

Rhizome weight (g)

Numberofpla

nts

Proportion


16/24


Sheva National Park than el Arad National Park, while a dierence in percentage oplants that produced mature ruits was less pronounced (Fig. 6). Plants o native geo-graphic origin had no advantage at either location.

A high percentage o owering plants at one location (el Beer Sheva National

Park) indicates high potential seed productivity in the living collection. Te low per-centage o plants that set ruits appears to result rom low numbers o pollinators inthis area. Tereore the genetic reuges can be a source o seeds or relocation onceartifcial pollination is provided.

Large scale relocation experiment

High survival rates were observed in the frst year ater introduction at all locations,and the highest number o reproducing plants was observed at Oakim and LahavNorth (Fig. 7). At Har Amasa, plant above-ground biomass was browsed by grazinglivestock, thus, assessment o reproduction was not possible. wo years ater the intro-duction a dierence in plant survival rates among the locations started to become obvi-ous (Fig. 7). Grazing at Har Amasa again prevented assessment o plant reproduction.

Te most unexpected and counterintuitive result was zero reproduction at twoexperimental sites established in close proximity to the natural populations, G-G and-A. In both cases experimental locations were established on an adjacent hill slope.Tis indicates the importance o microscale conditions or relocation success. At the

Figure 6. Population name, number o genetically distinct individuals (in parentheses), and percentage

o owered and ruited plants two years ater creation o two quasi in situ collections in el Beer Sheva and

el Arad National Parks, respectively.

0

20

40

60

80

100

N

(37)

M

(21)

F

(26)

S

(67)

N

(30)

M

(18)

F

(28)

S

(61)

Populations

%

Tel Beer Sheva Tel Arad

Arad

Goral

Flowering Fruiting

Regional

origin:


17/24


Figure 7. Survival and reproduction oI. atrouscaone year ater experimental introduction. en large

(> 20 g) and 30 small (510 g) rhizomes o Goral Hills and Arad Valley origin were introduced at each site.

Plants

Ofakim Tel Beer

Sheva

Nevatim Lahav

North

Tel Arad Har

Amasa

01

2

3

4

5 reproduction

0

10

20

30

40 survival2007

Introduction sites

0

10

20

30

Ofakim Tel BeerSheva

Nevatim LahavNorth

Tel Arad HarAmasa

0

2

4

68

10

GvaotGoral

Goral origin - large

Arad origin - large

Goral origin - small

Arad origin - small

2008

Plants

reproduction

survival


18/24


Figure 8. Survival and reproduction o I. atrouscaone year ater experimental introduction at Lahav

North Reserve. Sixty-two rhizomes o Goral Hills origin with equal representation o dierent size classes

were introduced at each introduction plot.

Total22

22

20

20

21

21

19

19

18

18

17

17

16

16

15

15

14

14

13

13

12

12

11

11

10

10

9

9

8

8

7

7

6

6

5

5

4

4

3

3

2

2

1

1

0

0

10

10

20

20

30

30

40

40

50

50

60

60 Flowered

Fruited

2007

2008Plants

Introduction plots

Lahav North Reserve both survival and reproduction o plants were consistently highduring two years o observations. Tis strongly supports our decision made in 2006 tostart experimental microscale relocation at the Lahav North Reserve. At the Oakimsite reproduction was high in the frst year but dropped dramatically in the secondyear ater planting.

Small scale relocation experiment

Te number o plants observed at the 22 microsites in the Lahav North Reserve oneyear ater introduction ranged rom 25 to 52 plants (out o 62 introduced) with nosignifcant dierence between microsites (G-test, G

.05,21= 9.2, p > 0.05; Fig. 8). Te mi-

crosites did not dier either in the number o plants that set ruits (G-test, G.05,21

= 32.4,p > 0.05), but diered in numbers o owering plants (G-test, G

.05,21= 36.8, p < 0.05).

wo years ater the introduction, the range o surviving plants per microsite wasbetween 33 and 53, generally higher than the previous year records. Tis indicates

that some plants were not counted in the frst year census, perhaps due to rhizomesdormancy. As in the frst year, no microsite dierence was observed or plant survivalin the second year (G-test, G

.05,21= 20.0, p > 0.05), but numbers o reproducing plants

were signifcantly dierent among microsites (G-test, G.05,21

= 74.2, p < 0.001; Fig. 8).


19/24


Figure 9. Map o the Lahav North Reserve with 22 microsites at which identical sets o I. atrousca

rhizomes were planted.

Kibbutz Lahav

Lahav North Nature Reserve

Contrary to the frst year, no ower set ruit at any microsite in the second year. All theowers were consumed by grasshoppers and caterpillars, indicating the important roleo biotic interactions at the Lahav North site.

Discussion

Distribution in the Negev and population demography

Te observed dierences in stage structure (i.e. the requency o lie-cycle stages)between the two populations correspond to two types o demographic behavior, theinvasive or dynamic (Gvaot Goral) and normal or stable (el Arad) (Rabot-nov 1969, 1985, Oostermeijer et al. 1994). Te ormer is characterized by a higherproportion o immature plants relative to the adults, while in the latter the adultspredominate and the young individuals are low in number. Tese two populationtypes are usually associated with dierent succession stages o the local vegetationcommunity, but in the two I. atrouscapopulations studied no dierence was ap-

parent with respect to the succession stage. One major dierence between the twopopulation locations is in aridity, and the observed dierence in a proportion o im-mature plants appears to be due to higher survival o seedlings (although survival o

juveniles does not dier) at less xeric Gvaot Goral site. Nonetheless, it is too early to


20/24


draw conclusions about the long-term dynamics o these two populations. Te latterrequires a multi-year census coupled with records o annual rainall and assessmento grazing pressure.

Te two groups are separated rom each other by a distance o ca 20 km with hard-

ly any gene ow between them. Dierent environmental conditions (soil, rainall) andanthropogenic impact (intensive grazing vs agriculture) may have caused dierentialselective responses in the two regions. Tereore an I. atrouscaconservation strategymust be based on the assumption that ecologically important (i.e. adaptive and causedby biotic/abiotic environmental variation) exists within I. atrouscain the Negev andregional criterion (Goral Hills vs Arad Valley range subdivision) is a frst approxima-tion o this variation. Tis assumption has several implications or this species exandin situ conservation.

Ex situimplications

I plants in two regions are adapted to dierent environmental conditions, samplingand maintenance o living collections must be done or each region separately. Mix-ing or physical proximity o plants having dierent regional origin must be prevented.I, due to logistical limitations, plants are maintained in the same location, measuresmust be taken to prevent spontaneous hybridization (e.g. removal o immature ruits).On the other hand, interbreeding o plants originating rom dierent populations

within the same region, is desired to decrease risk o inbreeding depression and sel-incompatibility. Te latter negative eects were detected in ragmented populations oI. bismarckiana, a close relative to I. atrousca(Segal et al. 2007).

In our study, plants rom fve populations oI. atrouscain the Negev were plantedat two National Parks, creating two duplicates o the same living collection. Atercareul study o region-specifc environmental conditions, anthropogenic impacts andpopulation demography we concluded that we should divide our collection based on aregional criterion. In spite o the initial proximal planting o plants rom two regions,

no spontaneous hybridization occurred during two years o collection maintenancebecause o the precautions described above.Ater removal and re-planting o populations representing the Goral Hills area,

into their region-specifc location in el Beer Sheva National Park, and populationsrom the Arad Valley area into their region-specifc location at el Arad NationalPark, the next step in applyingquasi in situ conservation, using plants in the livingcollections or seed propagation. In a case o low ruit set due to limited availabilityo natural pollen vectors (Eucerabees; Sapir et al. 2005) randomly applied artifcialpollination should be perormed. Te seeds obtained can be treated to reduce strong

innate dormancy, and germinated in mass. Young plants with rhizomes acceding 4 gcan be used or in situ actions, which should be perormed with plants o properregional origin.


21/24


In situimplications

Rapid destruction oI. atrouscanatural environment in the Northern Negev due toheavy anthropogenic impact on the one hand, and lack o nature reserves that contain

populations oI. atrouscain the Negev, on the other hand, leaves very limited optionsor conservation o this species. Declaration o new protected areas in the northern Ne-gev is very problematic because o economic, demographic and political issues. Tere isvirtually no vital alternative to relocation, i.e. introduction o the species into presum-ably suitable protected areas with no previous records o the species. At the same time,the choice o such areas or I. atrouscain the Negev is limited.

It is too early to draw conclusions rom our relocation experiments, started in2006, about actors limiting species distribution. At least several more years are neededor reliable conclusions, because among-year uctuations, as well as long-term eectsshould be considered. However, some general considerations about a choice o reloca-tion material can be done even at this stage. Using regional subdivision as a guidelineor successul relocation, creation o a new population within Goral Hills or Arad Val-ley region should be done using material rom the same region. I, however, a new pop-ulation location can not be ascribed to one o these regions, possible options includematerial o single regional origin (either Goral or Arad) or a mix o two. Although lacko local adaptation is not an issue here, hybridization o two ecotypes may result in adisruption o coadapted gene complexes, high genetic load and low average ftness oplants in the new population. As a result relocation success may be low. Without reloca-tion experiments, it is impossible to decide which o two plant origins is more suitable.

Conclusions

We conclude that the proposed approach assessing ecological importance, and usingthis inormation or both, exand in situ conservation is suitable or endangered speciesthat are distributed over areas with complex and variable ecological conditions. We

hope that detailed guidelines developed rom the above approach or: (1) representa-tive sampling o populations; (2) collection maintenance; and (3) utilization or insitu actions will be used as a tool or e ciently solving specifc conservation problems.

Acknowledgments

We would like to thank Israel Nature and Parks Authority or fnancial support andvarious help during ulfllment o this project. We thank A. Adout, L. Burdeniy, G.

Dror, A. Dvir, M. Gvoa, D. Hawlena, S. Issacharo, A. Katz and M. Shushan or helpin feld and nethouse work, E. Even-Haim and A. Gvoa or help in creation o livingcollections, K. Lev or help in maps preparation.


22/24


References

Aguilar R, Quesada M, Ashworth L, Herrerias-Diego Y, Lobo J (2008) Genetic consequences

o habitat ragmentation in plant populations: susceptible signals in plant traits and meth-

odological approaches. Molecular Ecology 17: 51775188.Allen WH (1994) Reintroduction o endangered plants. BioScience 44: 6568.Araeh RMH, Sapir Y, Shmida A, Iraki N, Fragman O, Comes HP (2002) Patterns o genetic

and phenotypic variation in Iris hayneiand I. atrousca(Iris sect. Oncocyclus= the royalirises) along an ecogeographical gradient in Israel and the West Bank. Molecular Ecology

11: 3953.Atlas o Israel (1985) Atlas o Israel, Survey o Israel, el Aviv (3rd edition).

Avishai M, Zohary D (1980) Genetic a nities among the Oncocyclusirises. Botanical Gazette141: 107115.

Barrett SC, Kohn JR (1991) Genetic and evolutionary consequences o small population size in

plants: implications or conservation. Pp. 330 In: Falk DA, Holsinger KE (Eds) Geneticsand Conservation o Rare Plants. Oxord University Press, New York.

Blecher M (2007) Iris atrouscao the Nothern Negev: survey, preliminary results. Israel Natureand Parks Authority.

Bottin L, Cadre S Le, Quilichini A, Bardin P, Moret J, Machon N (2007) Re-establishment

trials in endangered plants: A review and the example oArenaria grandifora, a species onthe brink o extinction in the Parisian region (France). Ecoscience 14: 410419.

Brown ADH, Briggs JD (1991) Sampling strategies or genetic variation in ex situ collections

o endangered plant species. Pp. 99122 In: Falk DA, Holsinger KE (Eds) Genetics andConservation o Rare Plants. Oxord University Press, New York.

Brown ADH, Marshall DR (1995) A basic sampling strategy: theory and practice. Pp. 75111

In: Guarino L, Ramantha Rao VR (Eds) Collecting plant genetic diversity: technical guide-

lines. CAB International Wallington, UK.

Cranston DM, Valentine DH (1983) ransplant experiments on rare plants species rom Upper

eesdale. Biological Conservation 26: 175191.Danin A (1988) Flora and vegetation o Israel. Pp. 129157 in Y. Yom-ov and E. chernov,

eds. Te Zoogeography o Israel. Junk, Dordrecht.Danin A (2004) Distribution atlas o plants in the ora Palaestina area. Israel Academy or Sci-

ence and Humanities, Jerusalem.

Ellstrand NC, Elam DR (1993) Population genetic consequences o small population size: im-

plications or plant conservation. Annual Review in Ecology and Systematics 24:217242.Falk, D. A. 1987. Inegrated conservation strategies or endangered plants. Natural Areas Jour-

nal 7: 118123.Feinbrun-Dothan N (1986) Flora Palaestina. Israel Academy o Sciences and Humanities, Jerusalem.

Given DR (1987) What the conservationist requires o ex situ collections In: Bramwell D, Ha-

mann O, Heywood VH, Synge H (Eds) Botanic gardens and world conservation strategy.Academic Press, London.

Hedrick PW, Kalinowski S (2000) Inbreeding depression in conservation biology. Annual

Review in Ecology and Systematics 31: 139162.


23/24


Heywood VH, Iriondo JM (2003) Plant conservation: old problems, new perspectives. Biologi-

cal Conservation 113: 321335.Holland PG (1980) ransplant experiments with trout lily at Mont St. Hilaire, Quebec Journal

o Biogeography 7: 261267.

Huord KM, Mazer SJ (2003) Plant ecotypes: genetic dierentiation in the age o ecologicalrestoration. rends in Ecology and Evolution 18: 147155.

Husband BC, Campbell LG (2004) Population responses to novel environments: implications

or ex situ plant conservation In: Guerrant EOJ, Havens K, Maunder M (Eds) Ex situ plant

conservation: Supporting species survival in the wild. Island Press, Washington.

Jae S (1988) Climate o Israel. Pp. 129157 In: Yom-ov Y, chernov E (Eds) Te Zoogeog-

raphy o Israel. Junk, Dordrecht.

Joshi J, Schmid B, Caldeira MC, Dimitrakopoulos PG, Good J, Harris R, Hector A (2001) Local

adaptation enhances perormance o common plant species. Ecology Letters 4: 536544.Keller LF, Waller DM (2002) Inbreeding eects in wild populations. rends in Ecology and

Evolution 17: 230241.Kushnir (1949) Lea spot diseases oIrisin Palestine. Palestine Journal o Botany, Jerusalem

series 4: 230-233.

Lande R, Barrowclough GF (1987) Eective population size, genetic variation, and their use in

population management. Pp. 87124 In: Soule ME (Ed) Viable populations or manage-ment. Cambridge University Press, Cambridge.

Linhart YB, Grant MC (1996) Evolutionary signifcance o local genetic dierentiation in

plants. Annual Review o Ecology and Systematics 27: 237277.Maunder M, Havens K, Guerrant EOJ, Falk DA (2004a). Ex situ methods: a vital but underused

set o conservation resources. Pp. 320 In: Guerrant EOJ, Havens K. Maunder M (Eds) Ex

situ plant conservation: Supporting species survival in the wild. Island Press, Washington.

Maunder M, Hughes C, Hawkins JA, Culham A (2004b) Hybridization in ex situ plant col-

lections: conservation concerns, liabilities, and opportunities. Pp. 325364 In: Guerrant

EOJ, Havens K, Maunder M (Eds) Ex situ plant conservation: Supporting species survival

in the wild. Island Press Washington.

Menges ES (2008) Restoration demography and genetics o plants: when is a translocation suc-

cessul? Australian Journal o Botany 56: 187196.Millar CI, Libby WJ (1991) Strategies or conserving clinal, ecotypic, and disjunct populationdiversity in widespread species. Pp. 149170 In: Falk DA, Holsinger KE (Eds) Geneticsand conservation o rare plants. Oxord University Press, New York.

Morton JK (1982) Preservation o endangered species by transplantation. Te Canadian Bo-

tanical Association Bulletin 15:32.

Newman D, Pilson D (1997) Increased probability o extinction due to decreased genetic eec-

tive population size: Experimental populations oClarkia pulchella. Evolution 51: 354362.Newman D, allmon DA (2001) Experimental evidence or benefcial ftness eects o gene

ow in recently isolated populations. Conservation Biology 15: 10541063.Oostermeijer JGB, Vantveer R, Dennijs JCM (1994) Population structure o the rare, long-

lived perennial Gentiana pneumonanthein relation to vegetation and management in theNetherlands. Journal o Applied Ecology 31: 428438.


24/24


Rabotnov A (1969) On coenopopulations o perennial herbaceous plants in natural coenoses.

Vegetatio 19: 8795.Rabotnov A (1985) Dynamics o plant coenotic populations. Pp. 121142 In: White J (Ed)

Te population structure o vegetation. Handbook o vegetation science, Junk, Dordrecht.

Sapir Y, Shmida A, Fragman O (2003) Constructing red numbers or endangered plant species- Israeli ora as a test case. Journal or Nature Conservation 11: 91107.

Sapir Y, Shmida A, Fragman O, Comes HP (2002) Morphological variation o the Oncocyclusirises (Iris : Iridaceae) in the southern Levant. Botanical Journal o the Linnean Society139: 369382.

Sapir Y, Shmida A, Neeman G (2005) Pollination oOncocyclusirises (Iris: Iridaceae) by night-sheltering male bees. Plant Biology 7: 417424.

Schaal B, Leverich WJ (2004) Population genetic issues in ex situ plant conservation. Pp. 267

285 In: Guerrant EOJ, Havens K, Maunder M (Eds) Ex situ plant conservation: Support-

ing species survival in the wild. Island Press, Washington.

Segal B, Sapir Y, Carmel Y (2007) Fragmentation and pollination crisis in the sel-incompatible

Iris bismarckiana(Iridaceae), with implications or conservation. Israel Journal o Ecology

and Evolution 52: 111122.Shimshi D (1979/80) wo ecotypes oIris atrouscaBak. and their relations to man-modifed

habitats. Israel Journal o Botany 28: 8086.Shmida A, Pollak G (2007) Red Data Book: Endangered Plants o Israel. Israel Nature and

Parks Authority.

allmon DA, Luikart G, Waples RS (2004) Te alluring simplicity and complex reality o

genetic rescue. rends in Ecology & Evolution 19: 489496.Uma Shaanker R, Ganeshaiah KN (1997) Mapping genetic diversity o Phyllanthus emblica:

Forest gene banks as a new approach or in situ conservation o genetic resources. Current

Science 73: 163168.Uma Shaanker R, Ganeshaiah KN, Nageswara Rao M, Ravikanth G. (2001) A new approach

to conservation o genetic resources o orest trees: promise and processes. Pp. 263271 In:Uma Shaanker R, Ganeshaiah KN, Bawa KS (Eds) Forest genetic resources: Status, threats

and conservation strategies. Oxord and IBH Publishing Co. Pvt. Ltd

Uma Shaanker R, Ganeshaiah KN, Nageswara Rao M, Ravikanth G. (2002) Forest gene banks a new integrated approach or the conservation o orest tree genetic resources. Pp. 229235 In: Engels JMM, Brown AHD, Jackson M (Eds) Managing plant genetic resources.

CABI Publishing, Nosworthy. UK.

Volis S, Mendlinger S, Ward D (2002) Dierentiation in populations oHordeum spontaneumalong a gradient o environmental productivity and predictability: lie history and local

adaptation. Biological Journal o the Linnean Society 77: 479490.von Bothmer R, Selberg O (1995) Strategies or the collecting o wild species. Pp. 93111 In:

Guarino L, Ramantha Rao VR (Eds) Collecting plant genetic diversity: technical guide-

lines. CAB International Wallington, UK.

quasi in situ conservation

Documents