Adaptation of Meloidogyne spp. to drought stress · Meloidogyne spp. is a group of obligatory plant...
Transcript of Adaptation of Meloidogyne spp. to drought stress · Meloidogyne spp. is a group of obligatory plant...
Literature Review and Research Proposal
on
Adaptation of Meloidogyne spp. to drought stress
Academic Year 2014-2015
Submitted by
Md. Iqbal Hossain
Postgraduate International Nematology Course (PINC)
Faculty of Science, Department of Biology, Ghent University,
Ghent 9000, Belgium
Promoter
Prof. dr. Wim Wesemael
Co-promoter
Prof. dr. Roland N. Perry
Contents
Part A: Literature Review ........................................................................................................................ 1
1. Introduction ................................................................................................................................. 1
2. Importance of Meloidogyne .......................................................................................................... 1
3. Life cycle biology of Meloidogyne sp. .......................................................................................... 2
4. Adaptation strategies in Plant parasitic nematodes ........................................................................ 3
5. Effect of temperature on different life stages of nematodes ........................................................... 5
6. Adaptation of nematodes in cold stress ......................................................................................... 7
7. Adaptation of nematodes in osmotic stress ................................................................................... 8
8. Biochemical changes at different adaptation mechanism .............................................................. 9
Part B: Proposal..................................................................................................................................... 11
1. Background Information ............................................................................................................ 11
2. Hypothesis ................................................................................................................................. 12
3. Experimental procedure ............................................................................................................ 12
3.1. Culturing of nematodes ..................................................................................................... 12
3.2. Collection of egg masses .................................................................................................... 12
4. Adaptibility testing .................................................................................................................... 13
4.1. Experiment: Determine the survival capability of Meloidogyne spp. at different generations13
Part C: References ................................................................................................................................. 14
Part D: Addendum ................................................................................................................................. 27
Table 1. Time schedule and expected deliverables ............................................................................. 27
1
Part A: Literature Review
1. Introduction
Nematodes are bilaterally symmetrical multicellular worm like animals, the most abundant metazoa on
earth. They are found in almost all ecology (Ferris et al., 2001); even, they are discovered as an
anhydrobiotic (Moens & Perry, 2009). Nevertheless, a layer of liquid is essential for their activity and
motility. Environmental factors such as temperature, relative humidity etc. have also an effect on the
survival mechanism of nematodes.
Nematodes are living as free-living organism, plant-parasitic and animal-parasitic. Among the 25000
described nematode species (Hodda, 2011 ), about 4100 species are plant-parasitic in nature (Decraemer
& Hunt, 2013). Most of the plant-parasitic nematodes (PPN) attack the roots of plants but very few are
capable to cause disease on above ground plant parts. They cause several diseases of plants that results in
heavy losses in crop production all over the world regarding quality and quantity. About 12.3% of annual
agricultural crop production are destroyed by them which cost $157 billion (Hassan et al., 2013).
Distribution and severity of PPN species is diverse. For example, Nacobbus spp. are found only in North
and South America; species like the carrot cyst nematode Heterodera carotae is host specific whereas
Meloidogyne spp. are globally distributed with a large host range (Nicol et al., 2011). Furthermore, root-
knot nematodes (Meloidogyne spp.) are obligate plant parasites and one of the most destructive PPN
genus (Hunt & Handoo, 2009).
2. Importance of Meloidogyne
Root-knot nematode (Meloidogyne spp.) is a polyphagus group of obligate plant-parasitic nematodes
which has highly adaptive capability and has been found worldwide (Karssen et al., 2013). It causes
disease in thousands of monocotyledonous and dicotyledonous plants (Eisenback & Hirschmann, 1991) .
2
Nearly100 species are discovered in this genus (Onkendi et al., 2014) but only six of them are most
widely distributed and responsible for considerable damage (Adam et al., 2007). Among them,
Meloidogyne incognita, M. javanica and M. arenaria are highly abundant in tropical climates but also in
green houses of temperate regions; M. chitwoodi, M. fallax and M. hapla are major species in temperate
climate. Furthermore, in respect of changing global trade pattern and crop production system, M. minor
and M. enterolobii species are becoming emerging threats (Wesemael et al., 2011) for the temperate and
tropical region respectively. As a result, M. chitwoodi, M. fallax and M. enterolobii have been reported as
quarantine pest by European and Mediterranean Plant Protection Organization (EPPO) (EPPO, 2011).
Two closely related cryophilic species M. chitwoodi and M. fallax were first identified at Pacific
Northwest of USA in 1980 (Golden et al., 1980) and at Baexem, the Netherlands in 1992 (Karssen,
1996), respectively. M. chitwoodi was also recorded in Argentina, Belgium, Germany, Netherlands,
Portugal, Switzerland, Russia, Australia, Mexico and South Africa (EPPO, 2004; Karssen et al., 2013),
M. fallax was observed in France, Belgium, Switzerland, UK and Germany (Dahler et al., 1996; Schmitz
et al., 1998; Fourie et al., 2001; Marshall et al., 2001; Nobbs et al., 2001; Waeyenberge & Moens, 2001;
Karssen et al., 2013). In Belgium, both species are causing severe quality damage to vegetables and
turning into a threat to food canning industries (Wesemael & Moens, 2008). Besides, M. hapla is mostly
associated with different dicot plant where as M. minor is observed only two times in potato field but very
common in several sport grounds in UK, Netherlands and Belgium golf courses along with M. naasi
(Karssen et al., 2004; Viaene et al., 2007).
3. Life cycle biology of Meloidogyne sp.
Meloidogyne spp. is a group of obligatory plant pathogenic nematodes, endoparasitic in nature. Females
are sedentary and remain inside the root tissue. They lay eggs in a confined gelatinous egg sacs (Karssen
et al., 2013). They complete their first moulting inside the eggs. Second-stage juveniles (J2) are hatched
from eggs and start searching for a host plant. Generally, they enter into the host tissue near the root tip by
3
physical means (stylet) as well as cell wall degrading enzymes (Wieczorek et al., 2014). They move
intercellularly in the cell wall compartment towards root tip and turn around when they reach the apical
meristem cells and move further to reach the differentiating vascular zone (Wyss et al., 1992; Goto et al.,
2013). There, they look for cells to induce them as a multinucleate giant cells (Bartlem et al., 2014) that
also act as transfer cells (Jones & Northcot, 1972). For their growth and development, they take nutrients
from these cells and follow 3 successive moults to be adults. Parthenogenetic reproduction is common for
root-knot nematodes (Castagnone-Sereno, 2006). Adult females start to lay eggs, while vermiform
malesleave the host tissue.
4. Adaptation strategies in plant-parasitic nematodes
According to Wharton (2004), ‘survival strategies’ refer to a specific behavior of organisms at their
biological and physical challenges. During their life cycle, different plant-parasitic nematodes also follow
several survival strategies against environmental extremes and host response (Perry, 2011). Two types of
dormancy, ‘quiescence’ and ‘diapause’ often lengthen survivability of unhatched larvae in soil living
nematodes including RKN (Perry, 1989). Cryobiosis, thermobiosis, anoxybiosis, osmobiosis and
desiccation are different survival mechanisms that are also observed in nematodes (Wright & Perry,
2006). First discovered plant-parasitic nematode, Anguina tritici has also special adaptation aptitude
against desiccation (Needham, 1743). Commonly, life cycle of a PPN is divided into different distinct
stages such as egg, four juvenile stages (J1, J2, J3 and J4) and adults and different major PPN also
exhibits different adaptation mechanism at their different life stages.
Eggs of RKN are laid in mucoid protein mass that provides safety to eggs water loss and predators
(Eisenback, 1985). Furthermore, extreme temperature makes this glycoprotein shriveled and hard that
promotes mechanical pressure and hinders the hatching of J2 larva that is prone to drought environment
(Wright & Perry, 2006). Additionally, gelatinous matrix defends the eggs from the attack of some soil
microorganism as was observed in M. javanica (Orion & Kritzman, 2001). During dry conditions, a dried
4
eggshell can also decrease water loss rate by changing its permeability (Ellenby, 1968). Additional
research on eggshell permeability was done by Wharton (1980) and he observed that the lipid layer of the
eggshell played a major role for lowering the water loss during desiccation. Not all PPN have survival
capability. Mostly, the species with limited hosts such as potato cyst nematodes (Globodera rostochiensis
and G. pallida) gained well adaption features for undesirable circumstances (Perry, 2002). The unhatched
larvae of this nematode can survive many years in cyst without host (Turner & Rowe, 2006). Ellenby
(1946) observed that the permeability of cyst wall exterior and eggshell of G. rostochiensis changed at
desiccated conditions which helped cyst wall and eggshell to restrict their water losing rate compared to
favourable conditions. This helps the unhatched susceptible J2 to survive in the egg and hatching factors
(host root exudates) are obligatory for this nematode to hatch their J2 (Wright & Perry, 2006). J2 of
soybean cyst nematode Heterodera glycines hatched in water at optimum conditions but at the end of the
plant growing season when environment is becoming complex, most of the J2 remains in the cyst and
hatching is solely dependent on hatching factors, irrespective to the origin of hatching factors; i.e. natural
(Ishibashi et al., 1973) or artificial (Thompson & Tylka, 1997). Other cyst nematodes, such as H. carotae
(Greco, 1981), H. goettingiana (Greco et al., 1986), H. sacchari (Ibrahim et al., 1993) contain the same
characteristics. Even, RKN, M. chitwoodi and M. triticoryzae (Gaur et al., 2000; Wesemael et al., 2006)
also showed the same features for hatching of J2.
Under drying condition, species of Anguina and Ditylenchus showed coiling and clumping like features in
their life cycle that helps to avoid water loss by reducing their surface (Crowe & Madin, 1975).
Ditylenchus myceliophagus also lessen their water loss becoming coiled (Womersley, 1978).
Furthermore, at the last stage of the crop growing season, D. dipsaci, stops their development at J4 stage
due to shortage of food and make large aggregations and start coiling. This attribute known as ‘eelworm
wool’ that helps them to remain alive for many years at desiccated condition by the sacrifice of peripheral
J4s of this aggregation (Ellenby, 1969). Rice grain nematodes, Aphelenchoides besseyi also stops their
multiplication at ripening stage of rice and adults become coiled and clumped which helps them surviving
5
for 2-3 years with dry grains (Perry & Moens, 2011). On the other hand, J2 of 2 gall producing nematode
Anguina tritici and A. pacificae become anhydrobiotic but remain uncoiled and survived many years
(McClure et al., 2008). So, coiling is not obligatory for survival during desiccation. Nevertheless, D.
dipsaci and A. tritici, can overcome desiccated environment and survive many years in above ground
plant parts (Moens & Perry, 2009). Anguina tritici, D. dipsaci and Tylenchus have been showed
potentiality of being enliven from desiccation after 20 year (Perry & Moens, 2011), 28 years (Fielding,
1951) and 39 years (Steiner & Albin, 1946) respectively. Cuticle lipid content of desiccated J4 of D.
dipsaci and J2 of A. tritici have been increased compared to hydrated juveniles of those nematodes (Bird
& Buttrose, 1974; Preston & Bird, 1987). Sheath retaining is also a survival mechanism against
desiccated condition. Young adults of Rotylenchulus reniformis remains confined with all 3 moulted
cuticle of their larval stage which facilitates them of being dormant in adverse condition until situation
becomes amiable for their survival (Gaur & Perry, 1991). Entomopathogenic nematode Heterorhabditis
megidis also retains cuticle sheath that provides them lowering their drying in unfavorable environment
(Menti et al., 1997).
Dauer phenomenon is a special characteristic of nematodes that helps them to survive at stress condition.
Dauer is very common in C. elegans where dauer larvae restrict its biological activity and survive periods
at desiccated situation (Kenyon, 1997). J2, J3, or J4 stages are performed as dauer in A. tritici, C. elegans
and D. dipsaci respectively (Bird & Bird, 1991). Pine wood nematode Bursaphelenchus xylophilus, also
contains a dauer stage that facilitates the transportation to pine trees with the help of insect vector
Monochamus (Mota & Vieira, 2008).
5. Effect of temperature on different life stages of nematodes
Temperature is known as influential on life cycle and biology of nematodes. Different activities such as
growth and development, mobility, infection capability and hatching are affected by its surrounding
temperature (Davide & Triantaphyllou, 1968; Wallace, 1971; Tzortzakakis & Trudgill, 2005).
6
Meloidogyne arenaria requires at least 12.2°C with short photoperiod for their egg mass production
(Yeon et al., 2003).
For certain range of temperature; development of nematodes increase with enhancing of temperature
which is termed as temperature niche breadth (Anderson & Coleman, 1982). For example, growth
development rate of C. elegans (wild type) increases 2.1 times and 1.3 times when they have been kept at
25°C and 20°C respectively instead of 16°C (Stiernagle, 2006). Additionally, temperature plays a key role
on host-nematode association in soil ecology. Nematode resistant hosts, for example: tomato, cotton and
other crops became vulnerable at increasing thermopiriodism (Ferris et al., 2013). Meloidogyne resistance
gene, Mi becomes ineffective when a host has been kept at higher temperature continuously (Holtzman,
1965; Laterrot & Pecaut, 1965; Dropkin, 1969). Furthermore, same result was observed at in vitro studies,
where host resistence against M. incognita has been lost due to heat stress (Haroon et al., 1993). Several
experiments were done to reveal the effect of temperature on nematodes. Ploeg and Maris (1999)
examined the effect of five soil temperatures on fecundity rate and period of M. incognita on tomato host
plant. They can complete their life within an average of 16.2°C and 30°C. Furthermore, optimum
temperature, moisture and aeration are obligatory for hatching out of Meloidogyne juveniles (Bergeson,
1959). Meloidogyne javanica and Heterodera glycines were tested on susceptible and resistant hosts at 5
different temperatures (20°C, 24°C, 26°C, 28°C and 32°C). Parameter on biological activity such as
quantity of egg-masses, total eggs, females and successful infestation (%) of J2 for M. javanica were
significantly higher at 28°C over other temperatures on both type of hosts. Same temperature also
significantly increases J2 infective capability (%), amount of female’s total population (Female no. + no.
of cyst) for H. glycines on a susceptible host. However, temperature did not show any effect on the total
population of cyst nematodes on resistant plants. Females of M. javanica produced a higher number of
eggs in a susceptible host at 4 different soil temperatures (20°C, 26°C, 28°C and 32°C) but a significant
increase was only observed at 32°C (Campos et al., 2011). An observation was done on survival character
of eggs of two RKN under different soil temperatures in laboratory along with field observation. Eggs of
7
M. hapla were better in viability than that of M. javanica but became destroyed when kept for a longer
period at -2°C in soil. Opposite results were seen when eggs of both species were kept at 36°C and 40°C.
This proves overwintering capability of M. hapla and M. javanica in field at temperate and tropical region
respectively (Daulton & Nusbaum, 1961).
6. Adaptation of nematodes in cold stress
Nematodes that can be recognized as a cold survivor are capable to carry on their life after facing freezing
temperatures for longer periods; nematodes of temperate regions which can survive at freezing
temperatures are included in this group (MacGuidwin & Forge, 1991; Dimander et al., 1998). Nematodes
that are living in Arctic (Coulson & Birkemoe, 2000) and Antarctic region (Wharton, 2003) along with
sea ice (Gradinger, 2001), alpine sites (Hoschitz & Kaufmann, 2004) and glaciers (Christner et al., 2003;
Hodson et al., 2008) definitely have special adaptation behaviour to cold in their life cycle (Wharton,
2011).
The main constraints to survive in freezing conditions are destruction of body cells especially intracellular
freezing due to osmotic stress (Mazur, 1984). There are nematodes that can tolerate intracellular freezing
(Wharton & Ferns, 1995; Salinas-Flores et al., 2008). Panagrolaimus davidi is one of the nematodes
collected from the Antarctic (Wharton, 2011) that shows this aptitudes (Wharton & Ferns, 1995; Wharton
et al., 2003; Wharton et al., 2005). Feeding behavior has an effect on the tolerance capability of P. davidi
(Raymond & Wharton, 2013). Panagrolaimus davidi can also survive against extracellular ice
development (Wharton et al., 2005). Generally, nematodes survive in cold as being anhydroboitic but
desiccation should be done before exposure to freezing (Wharton, 2002). Nevertheless, P. davidi
performs an external dehydration tactic which is known as ‘cryoprotective dehydration’ (Wharton &
Barclay, 1993). Cell membranes of this nematode act as a little barrier to ice formation (Wharton & Ferns,
1995). The embryo or J1 remains in supercool condition inside eggs when ice is around the eggs.
Eggshell plays key role to protect eggs from adverse freezing (Wharton, 1994).
8
This ‘supercool’ characteristic is also observed in unhatched J2 of cyst nematodes, G. rostochiensis and
G. pallida when cyst were enclosed in ice, placed at −38°C. Cyst wall and eggshell provide support to
keep alive J2 against freezing (Wharton et al., 1993; Wharton & Ramløv, 1995; Devine, 2010).
Acclimatization to low temperatures can increase the adaptation capability of nematodes to cold stress
(Ehlers et al., 2005). It was observed in entomopathogenic nematodes, such as in Steinernema feltiae, S.
anomalae and H. bacteriophora (Brown & Gaugler, 1996). Furthermore, placing J2 of M. hapla at 4°C
for 12 h also increases their cold tolerance capability to sustain in 5% polyethylene glycol (at −4°C)
(Forge & MacGuidwin, 1990, 1992).
7. Adaptation of nematodes in osmotic stress
Maintaining osmotic pressure between the body fluid (pseudocoelomic fluid) and the surrounding water is
challenging for nematodes. They keep themselves isometric to hyperosmotic pressure in different
habitats. Fresh water nematodes are hyperosmotic in nature but their body fluid concentration remains
relatively constant (Wright, 2004) whereas marine nematodes retain themselves isometric that helps them
surviving in sea water (Wright, 2004). However, habitat of estuarine nematodes is affected by marine and
fresh water current where ionic composition and osmotic pressure are always changing at diurnal period
(Forster, 1998).
Nematodes living in sea do not face any problem in saline water. About 3.5% salinity is found in sea
water which is equivalent to 0.06 N NaCl or 1000 mmol/kg. Some nematodes are observed in terrestrial
springs that are rich in different minerals (Hodda et al., 2006). Even, nematodes such as Microlaimus,
Theristus and Bathylaimus are reported to live in > 10% salinity habitat; for example intertidal habitats of
Zanzibar western coast (Olafsson, 1995). Furthermore, nematodes are highly adapted in saline lakes of
Australia where NaCl concentration is at least 9.3% (Bayly & Williams, 1966; Deckker & Geddes, 1980).
Nematodes are likely to avoid osmotic stress. They like to live in less stressful places. The free living
nematode, C. elegans moves toward less concentrated areas (Choe & Strange, 2007). Moreover, J2 of M.
9
hapla (Prot, 1978) and M. incognita (Le Saux & Queneherve, 2002) perform the same characteristics and
show avoiding actions to higher concentrated habitats. Furthermore, Steinernema carpocapsae (Pye &
Burman, 1981) and Rotylenchulus reniformis (Riddle & Bird, 1985) also show the same survival habit.
According to Willmer et al. (2005), nematodes can overcome osmotic stress by two mechanisms, either
changing their own body fluid concentration like to outer fluids concentration or being tolerant to external
concentration; and they are termed as osmoconformers and osmoregulators respectively. Ascarissuum
(Hobson et al., 1952) and J3 of P. decipiens (Fuse et al., 1993) are the best examples of osmoconformers
and osmoregulators respectively. However, some organism perform osmobiotic features to avoid external
high concentration (Kellin, 1959).
Cuticle and eggshells (Wharton, 1980) also provide physical barrier to restrict water flux that also help
nematodes to survive against osmotic stress. Less permeable cuticle reduces water loss rate that protects
C. briggsae in stress environment but the resistance of cuticle lessen when nematodes become old (Searcy
et al., 1976). Additionally, this physical tolerance aptitude (Wharton et al., 1988) is also observed in D.
dipsaci when they have been kept in 1.6 M NaCl for 1 day (Viglierchio et al., 1969). On the other hand,
high permeable cuticle of isosmotic marine nematodes, offer them to endure well in saline sea water
(Wharton, 2011).
8. Biochemical changes at different adaptation mechanism
Trehalose is a disaccharide that provides nematodes tolerance against high temperature (Jagdale &
Grewal, 2003), desiccation, cold or different global stresses by accumulating this natural chemical into
the nematode body (Grewal et al., 2006). Panagrolaimus davidi (Wharton et al., 2000), N. battus eggs
(Ash & Atkinson, 1983), S. kushidai (Ogura & Nakashima, 1997), and S. carpocapsae (Qiu & Bedding,
1999) accumulated higher trehalose when they are exposed to cold. Enhancing desiccated stress (Perry et
al., 2012) as well as higher temperature stress (Jagdale & Grewal, 2003) causes more metabolism of
10
trehalose in EPN genera Steinernema. Moreover, trehalose synthesis increases in another EPN genera
Heterorhabditis exposed to both high or low temperature (Jagdale et al., 2005).
Synthesis of heat shock protein also increase stress tolerance capability in nematodes. Accumulation of
heat shock protein increases at exposure to heat or cold stress (Devaney, 2011). Transgenic
Heterorhabditis bacteriophora that contains the heat shock protein gene hsp70A enhances its
thermotolerance capability (Gaugler et al., 1997). Increasing formation of Hsp90 has been reported in
eggs at 5°C but the amount of that protein does not increase in J2 at the same temperature (De Luca et al.,
2009).
11
Part B: Proposal
1. Background Information
Plant-parasitic nematodes cause diseases of plants at roots and other parts of plants. They are responsible
to damage about 12.3% of annual crop production in the world that costs $157 billion (Abad et al., 2008).
Root-knot nematode (RKN), the most widely distributed obligatory plant-parasitic nematodes, are
polyphagous and the most economically damaging group of nematodes to agricultural production. The
average threshold limit to crops is generally from 0.5-2 juveniles/g of soil (Greco & Di Vito, 2009). Till
2013, 98 species (Jones et al., 2013) of this obligate nematode have been reported that can cause disease
to monocotyledons, dicotyledons, herbaceous and woody plants (Eisenback & Hirschmann, 1991).
Among them, Meloidogyne incognita, M. javanicaand M. arenariaare the most damaging nematodes in
tropics, M. chitwoodi, M. fallax, and M. hapla causes considerable crop loss in cooler regions (Adam et
al., 2007). Furthermore, M. chitwoodi and M. fallax are very important species due to their quarantine
status along with their damaging capability to economic crops like potato. These species are polycyclic at
optimum temperature in crop growing seasons (Brinkman et al., 1996). Due to climate change, southern
Europe and the Mediterranean countries become drier. Moreover, life cycle of temperate nematodes in
this region becomes more diversified that affects their survival mechanism as well as their infectivity rate
to plants. Proper managing and restricting distribution of these quarantine nematodes and knowledge on
survival mechanisms and infectivity of these nematodes is very much essential. To gain that knowledge it
is necessary to cope up the upcoming RKN problems in Europe at challenging warming climate. The
experiments in this thesis will be set up with the following objectives:
1. To investigate the adaptability and infectivity of Meloidogyne spp. at different temperatures
2. To examine the adaptability of Meloidogyne spp. to drought stress
12
2. Hypothesis
Main survival stage of Meloidogyne is egg mass which provides protection for eggs, J1 and J2
(unhatched) with the help of its gelatinous matrix at different harsh ecology. Egg mass will be kept at
different drought conditions (on the basis of temperature and moisture levels). Hatching capability,
survivability and infectivity of following generations will be key factors to assess their adaptive
capability. It is assumed that successive generations will become more adapted and as such more
aggressive.
3. Experimental layout
3.1. Culturing of nematodes
Root-knot nematodes, Meloidogyne spp. will be cultured on susceptible tomato plants (Solanum
lycopersicum cv. Moneymaker) in glasshouse at 20°C-26°C with 14 h light period at ILVO, Merelbeke,
Belgium. Tomato seedlings will be transplanted individually in plastic pots containing sterilized soil.
Freshly hatched J2 will be used to infect the susceptible plants for getting the egg masses.
3.2. Collection of egg masses
Egg masses will be collected from 12-16 weeks old tomato plants, after 8-12 weeks after inoculation.
Adhering soil should be discarded from plant roots and egg masses should be collected from roots using
sharp blade.
13
4. Adaptability testing
4.1. Experiment: Determine the survival capability of Meloidogyne spp. at different
generations
Collected egg masses will be put under different temperatures and relative humidities for certain time
where as control treatment will be the egg mass without any temperature treatment and at 100% RH. 1st
generation J2 will be calculated during a hatching experiment and they will be used to inoculate
susceptible tomato host plants. 2nd
generation egg masses will be collected and calculated and kept again
at different temperatures and relative humidities. This cycle will be continued during the time frame of
thesis work. In the glasshouse tomato plants with RKN will be stressed (drought stress) and egg masses
will be collected from these plants (if they are formed). J2 hatching from this egg masses will be
examined for adaptation to drought stress as described above.
14
Part C: References
Abad, P., Gouzy, J., Aury, J.-M., Castagnone-Sereno, P., Danchin, E.G.J., Deleury, E., Perfus-Barbeoch,
L., Anthouard, V., Artiguenave, F., Blok, V.C., Caillaud, M.-C., Coutinho, P.M., Dasilva, C., De
Luca, F., Deau, F., Esquibet, M., Flutre, T., Goldstone, J.V., Hamamouch, N., Hewezi, T., Jaillon,
O., Jubin, C., Leonetti, P., Magliano, M., Maier, T.R., Markov, G.V., Mcveigh, P., Pesole, G.,
Poulain, J., Robinson-Rechavi, M., Sallet, E., Segurens, B., Steinbach, D., Tytgat, T., Ugarte, E.,
Van Ghelder, C., Veronico, P., Baum, T.J., Blaxter, M., Bleve-Zacheo, T., Davis, E.L., Ewbank,
J.J., Favery, B., Grenier, E., Henrissat, B., Jones, J.T., Laudet, V., Maule, A.G., Quesneville, H.,
Rosso, M.-N., Schiex, T., Smant, G., Weissenbach, J. & Wincker, P. (2008). Genome sequence of
the metazoan plant-parasitic nematode Meloidogyne incognita. Nature Biotechnology 26, 909-
915.
Adam, M.A.M., Phillips, M.S. & Blok, V.C. (2007). Molecular diagnostic key for identification of single
juveniles of seven common and economically important species of root-knot nematode
(Meloidogyne spp.). Plant Pathology 56, 190-197.
Anderson, R.V. & Coleman, D.C. (1982). Nematode temperature responses - A niche dimension in
populations of bacterial-feeding nematodes. Journal of Nematology 14, 69-76.
Ash, C.P.J. & Atkinson, H.J. (1983). Evidence for a temperature-dependent conversion of lipid reserves
to carbohydrate in quiescent eggs of the nematode, nematodirus-battus. Comparative
Biochemistry and Physiology B-Biochemistry & Molecular Biology 76, 603-610.
Bartlem, D.G., Jones, M.G.K. & Hammes, U.Z. (2014). Vascularization and nutrient delivery at root-knot
nematode feeding sites in host roots. Journal of Experimental Botany 65, 1789-1798.
Bayly, I.A.E. & Williams, W.D. (1966). Chemical and biological studies on some saline lakes of south-
east australia. Australian Journal of Marine and Freshwater Research 17, 177-228.
Bergeson, G.B. (1959). The Influence of Temperature On the Survival of Some Species of the Genus
Meloidogyne, in the Absence of a Host 1). Nematologica 4, 344-354.
15
Bird, A.F. & Bird, J. (1991). The structure of nematodes. Academic Press, pp 94.
Bird, A.F. & Buttrose, M.S. (1974). Ultrastructural changes in the nematode Anguina tritici associated
with anhydrobiosis. Journal of ultrastructure research 48, 177-189.
Brinkman, H., Goossens, J.J.M. & Vanriel, H.R. (1996). Comparative host suitability of selected crop
plants to Meloidogyne chitwoodi Golden et al. 1980 and M. fallax Karssen 1996. Anzeiger Fur
Schadlingskunde Pflanzenschutz Umweltschutz (German) 69, 127-129.
Brown, I.M. & Gaugler, R. (1996). Cold tolerance of steinernematid and heterorhabditid nematodes.
Journal of Thermal Biology 21, 115-121.
Campos, H.D., Campos, S., Juliana, R., Campos, V.P., Carregal, P.D.S., Luis, H., Abreu, S.C., Lilian, S.,
Rodrigues, D.S. & Willian, J. (2011). Effect of soil temperature on infectivity and reprodution of
Meloidogyne javanica and Heterodera glycines in soybean cultivars. Ciencia E Agrotecnologia
35, 900-907.
Castagnone-Sereno, P. (2006). Genetic variability and adaptive evolution in parthenogenetic root-knot
nematodes. Heredity 96, 282-289.
Choe, K.P. & Strange, K. (2007). Molecular and genetic characterization of osmosensing and signal
transduction in the nematode Caenorhabditis elegans. Febs Journal 274, 5782-5789.
Christner, B.C., Kvitko, B.H. & Reeve, J.N. (2003). Molecular identification of bacteria and eukarya
inhabiting an Antarctic cryoconite hole. Extremophiles 7, 177-183.
Coulson, S.J. & Birkemoe, T. (2000). Long-term cold tolerance in Arctic invertebrates: recovery after 4
years at below-20°C. Canadian Journal of Zoology 78, 2055-2058.
Crowe, J.H. & Madin, K.A.C. (1975). Anhydrobiosis in nematodes: evaporative water loss and survival.
Journal of Experimental Zoology 193, 323-333.
Dahler, S., Gillet, S., Mugniéry, D. & Marzin, H. (1996). Discovery in France and characteristics of the
Dutch variant of Meloidogyne chitwoodi. Nematropica 26, 253.
Daulton, R.A.C. & Nusbaum, C.J. (1961). The Effect of soil temperature On the survival of the root-knot
nematodes Meloidogyne javanica and M. hapla 1. Nematologica 6 (4), 280-294.
16
Davide, R.G. & Triantaphyllou, A.C. (1968). Influence of the environment on development and sex
differentiation of root-knot nematodes. Nematologica 14, 37-46.
De Luca, F., Di Vito, M., Fanelli, E., Reyes, A., Greco, N. & De Giorgi, C. (2009). Characterization of
the heat shock protein 90 gene in the plant parasitic nematode Meloidogyne artiellia and its
expression as related to different developmental stages and temperature. Gene 440, 16-22.
Deckker, D.P. & Geddes, M.C. (1980). Seasonal fauna of ephemeral saline lakes near the Coorong
Lagoon, South Australia. Marine and Freshwater Research 31, 677-699.
Decraemer, W. & Hunt, D.J. (2013). Structure and Classification. In: Perry, R.N. & Moens, M. (Eds).
Plant nematology. 2nd ed. Wallingford, Oxfordshire, UK, CAB International, pp. 3-39.
Devaney, E. (2011). Thermobiotic Survival. In: Perry, R.N. & Wharton, D.A. (Eds). Molecular and
Physiological Basis of Nematode Survival. UK, CAB International, pp. 233-255.
Devine, K.J. (2010). Comparison of the effects of freezing and thawing on the cysts of the two potato cyst
nematode species, Globodera rostochiensis and G. pallida, using differential scanning
calorimetry. Nematology 12, 81-88.
Dimander, S.O., Höglund, J. & Waller, P.J. (1998). The origin and overwintering survival of the free
living stages of cattle parasites in Sweden. Acta Veterinaria Scandinavica 40, 221-230.
Dropkin, V.H. (1969). Necrotic reaction of tomatoes and other hosts resistant to Meloidogyne: reversal by
temperature. Phytopathology.
Ehlers, R.U., Oestergaard, J., Hollmer, S., Wingen, M. & Strauch, O. (2005). Genetic selection for heat
tolerance and low temperature activity of the entomopathogenic nematode–bacterium complex
Heterorhabditis bacteriophora–Photorhabdus luminescens. BioControl 50, 699-716.
Eisenback, J.D. (1985). Detailed morphology and anatomy of second-stage juveniles, males, and females
of the genus Meloidogyne (root-knot nematodes). An advanced treatise on Meloidogyne 1, 47-77.
Eisenback, J.D. & Hirschmann, T.H.H. (1991). Root-knot nematode: Meloidogyne spp. and races. In:
Nickle, W.R. (Ed.) Manual of Agricultural Nematology. New York, Marcel Dekker, pp. 191-274.
17
Ellenby, C. (1946). Nature of the cyst wall of the potato-root eelworm Heterodera rostochiensis,
Wollenweber, and its permeability to water. Nature 157, 302-303.
Ellenby, C. (1968). Desiccation survival in the plant parasitic nematodes, Heterodera rostochiensis
Wollenweber and Ditylenchus dipsaci (Kuhn) Filipjev. Proceedings of the Royal Society of
London. Series B. Biological Sciences 169, 203-213.
Ellenby, C. (1969). Dormancy and survival in nematodes. Symposia of the Society for Experimental
Biology.
EPPO (2004). Diagnostic protocols for regulated pests Meloidogyne chitwoodi and Meloidogyne fallax.
EPPO Bulletin 34.
EPPO (2011). PQR - EPPO database on quarantine pests (available online).
Ferris, H., Bongers, T. & De Goede, R.G.M. (2001). A framework for soil food web diagnostics:
extension of the nematode faunal analysis concept. Applied Soil Ecology 18, 13-29.
Ferris, H., Zheng, L. & Walker, M.A. (2013). Soil temperature effects on the interaction of grape
rootstocks and plant-parasitic nematodes. Journal of Nematology 45, 49-57.
Fielding, M.J. (1951). Observations on the length of dormancy in certain plant infecting nematodes.
Proceedings of the Helminthological Society of Washington 18, 110-112.
Forge, T.A. & Macguidwin, A.E. (1990). Cold hardening of Meloidogyne hapla second-stage juveniles.
Journal of Nematology 22, 101.
Forge, T.A. & Macguidwin, A.E. (1992). Impact of thermal history on tolerance of Meloidogyne hapla
second-stage juveniles to external freezing. Journal of Nematology 24, 262.
Forster, S.J. (1998). Osmotic stress tolerance and osmoregulation of intertidal and subtidal nematodes.
Journal of experimental marine biology and ecology 224, 109-125.
Fourie, H., Zijlstra, C. & Mcdonald, A.H. (2001). Identification of root-knot nematode species occurring
in South Africa using the SCAR-PCR technique. Nematology 3, 675-680.
Fuse, M., Davey, K.G. & Sommerville, R.I. (1993). Osmoregulation in the parasitic nematode
Pseudoterranova decipiens. Journal of experimental biology 175, 127-142.
18
Gaugler, R., Wilson, M. & Shearer, P. (1997). Field release and environmental fate of a transgenic
entomopathogenic nematode. Biological Control 9, 75-80.
Gaur, H.S., Beane, J. & Perry, R.N. (2000). The influence of root diffusate, host age and water regimes on
hatching of the root-knot nematode, Meloidogyne triticoryzae. Nematology 2, 191-199.
Gaur, H.S. & Perry, R.N. (1991). The role of the moulted cuticles in the desiccation survival of adults of
Rotylenchulus reniformis. Revue de Nématologie (French) 14, 491-496.
Golden, A.M., Obannon, J.H., Santo, G.S. & Finley, A.M. (1980). Description and SEM observations of
Meloidogyne chitwoodi n-sp (MELOIDOGYNIDAE), A root-knot nematode on potato in the
pacific northwest. Journal of Nematology 12, 319-327.
Goto, D.B., Miyazawa, H., Mar, J.C. & Sato, M. (2013). Not to be suppressed? Rethinking the host
response at a root-parasite interface. Plant Science 213, 9-17.
Gradinger, R.R. (2001). Adaptation of Arctic and Antarctic ice metazoa to their habitat. Zoology 104,
339-345.
Greco, N. (1981). Hatching of Heterodera carotae and H. avenae. Nematologica 27, 366-371.
Greco, N. & Di Vito, M. (2009). Population dynamics and damage Levels. In: Perry, R.N., Moens, M. &
Starr, J.L. (Eds). Root-knot nematodes. UK, CAB International, pp. 246-274.
Greco, N., Di Vito, M. & Lamberti, F. (1986). Studies on the biology of Heterodera goettingiana in
southern Italy. Nematologia Mediterranea 14, 23-39.
Grewal, P.S., Bornstein-Forst, S., Burnell, A.M., Glazer, I. & Jagdale, G.B. (2006). Physiological,
genetic, and molecular mechanisms of chemoreception, thermobiosis, and anhydrobiosis in
entomopathogenic nematodes. Biological Control 38, 54-65.
Haroon, S.A., Baki, A.A. & Huettel, R.N. (1993). An in vitro test for temperature sensitivity and
resistance to Meloidogyne incognita in tomato. Journal of Nematology 25, 83.
Hassan, M.A., Pham, T.H., Shi, H.L. & Zheng, J.W. (2013). Nematodes threats to global food security.
Acta Agriculturae Scandinavica Section B-Soil and Plant Science 63, 420-425.
19
Hobson, A.D., Stephenson, W. & Eden, A. (1952). Studies on the physiology of Ascaris lumbricoides II.
The inorganic composition of the body fluid in relation to that of the environment. Journal of
experimental biology 29, 22-29.
Hodda, M. (2011 ). Phylum Nematoda Cobb 1932. Animal biodiversity: An outline of higher-level
classification and survey of taxonomic richness. .Magnolia Press, Auckland, New Zealand, 3148,
63–95. pp.
Hodda, M., Ocana, A. & Traunspurcer, W. (2006). Nematodes from extreme freshwater habitats.
Freshwater Nematodes: Ecology and Taxonomy. pp. 179.
Hodson, A., Anesio, A.M., Tranter, M., Fountain, A., Osborn, M., Priscu, J., Laybourn-Parry, J. & Sattler,
B. (2008). Glacial ecosystems. Ecological monographs 78, 41-67.
Holtzman, O.V. (1965). Effect of soil temperature on resistance of tomato to root-knot nematode
(Meloidogyne incognita). Phytopathology 55, 990-&.
Hoschitz, M. & Kaufmann, R. (2004). Soil nematode communities of Alpine summits–site differentiation
and microclimatic influences. Pedobiologia 48, 313-320.
Hunt, D.J.& Handoo, Z.A. (2009). Taxonomy, identification and principal species. In: Perry, R.N., James,
M.M., and Starr., L.J. (Eds). Root-knot nematodes. UK CAB International, pp. 55-97.
Ibrahim, S.K., Perry, R.N., Plowright, R.A. & Rowe, J. (1993). Hatching behaviour of the rice cyst
nematodes Heterodera sacchari and H. oryzicola in relation to age of host plant. Fundamental
and Applied Nematology 16, 23-29.
Ishibashi, N., Kondo, E., Muraoka, M. & Yokoo, T. (1973). Ecological significance of dormancy in plant
parasitic nematodes I. Ecological difference between eggs in gelatinous matrix and cyst of
Hetrodera glycines ICHINOHE (Tylenchida: Heteroderidae). Applied Entomology and Zoology
8, 53-63.
Jagdale, G.B. & Grewal, P.S. (2003). Acclimation of entomopathogenic nematodes to novel temperatures:
trehalose accumulation and the acquisition of thermotolerance. International Journal for
Parasitology 33, 145-152.
20
Jagdale, G.B., Grewal, P.S. & Salminen, S.O. (2005). Both heat-shock and cold-shock influence trehalose
metabolism in an entomopathogenic nematode. Journal of Parasitology 91, 988-994.
Jones, J.T., Haegeman, A., Danchin, E.G.J., Gaur, H.S., Helder, J., Jones, M.G.K., Kikuchi, T.,
Manzanilla-Lopez, R., Palomares-Rius, J.E., Wesemael, W.M.L. & Perry, R.N. (2013). Top 10
plant-parasitic nematodes in molecular plant pathology. Molecular Plant Pathology 14, 946-961.
Jones, M.G.K. & Northcot, D.H. (1972). Multinucleate transfer cells induced in coleus roots by root-knot
nematode, Meloidogyne arenaria. Protoplasma 75, 381-395.
Karssen, G. (1996). Description of Meloidogyne fallax n sp (Nematoda: Heteroderidae), a root-knot
nematode from the Netherlands. Fundamental and Applied Nematology 19, 593-599.
Karssen, G., Bolk, R.J., Van Aelst, A.C., Van Den Beld, I., Kox, L.F.F., Korthals, G., Molendijk, L.,
Zijlstra, C., Van Hoof, R. & Cook, R. (2004). Description of Meloidogyne minor n. sp (Nematoda
: Meloidogynidae), a root-knot nematode associated with yellow patch disease in golf courses.
Nematology 6, 59-72.
Karssen, G., Wesmael, W.M.L. & Moens, M. (2013). Root-knot nematodes. In Perry, R.N. & Moens, M.
(Eds.) Plant nematology. 2nd ed. Wallingford, UK, CAB International.
Kellin, D. (1959). The problem of anabiosis or latent life: history and current concepts. Proc R Soc Lond
B.
Kenyon, C. (1997). Environmental factors and gene activities that influence life span. Cold Spring
Harbor Monograph Archive. pp. 791-813.
Laterrot, H. & Pecaut, P. (1965). Effect of high temperature on the resistance to the ariety Anahu to
Meloidogyne incognita. TGC Report 15, 38-39.
Le Saux, R. & Queneherve, P. (2002). Differential chemotactic responses of two plant-parasitic
nematodes, Meloidogyne incognita and Rotylenchulus reniformis, to some inorganic ions.
Nematology 4, 99-105.
Macguidwin, A.E. & Forge, T.A. (1991). Winter Survival of Pratylenchus scribneri. Journal of
Nematology 23, 198-204.
21
Marshall, J.W., Zijstra, C. & Knight, K.W.L. (2001). First record of Meloidogyne fallax in New Zealand.
Australasian Plant Pathology 30, 283-284.
Mazur, P. (1984). Freezing of living cells - mechanisms and implications. American Journal of
Physiology 247, C125-C142.
Mcclure, M.A., Schmitt, M.E. & Mccullough, M.D. (2008). Distribution, biology and pathology of
Anguina pacificae. Journal of Nematology 40, 226.
Menti, H., Wright, D.J. & Perry, R. (1997). Desiccation survival of populations of the entomopathogenic
nematodes Steinernema feltiae and Heterorhabditis megidis from Greece and the UK.. Journal of
helminthology 71, 41-46.
Moens, M. & Perry, R.N. (2009). Migratory plant endoparasitic nematodes: A group rich in contrasts and
divergence. Annual Review of Phytopathology 47, 313-332.
Mota, M.M. & Vieira, P. (2008). Pine wilt disease: a worldwide threat to forest ecosystems. Heidelberg,
Germany. Springer, pp. 450.
Needham, J.T. (1743). Concerning certain chalky concretions, called malm; with some microscopical
observations on the farina of Red Lilly, and worms discovered in Smutty Corn. Phil Transact
Royal Soc Lond 42, 634.
Nicol, J.M., Turner, S.J., Coyne, D., Den Nijs, L., Hockland, S. & Maafi, Z.T. (2011). Current nematode
threats to world agriculture. In: Jones, J., Gheysen, G. & Fenoll, C. (Eds). Genomics and
Molecular Genetics of Plant-Nematode Interactions. Springer Dordrecht Heidelberg London New
York, Springer Science+Business Media B.V. 2011, pp. 21-43.
Nobbs, J.M., Liu, Q., Hartley, D., Handoo, Z., Williamson, V.M., Taylor, S., Walker, G. & Curran, J.
(2001). First record of Meloidogyne fallax in Australia. Australasian Plant Pathology 30, 373-
373.
Ogura, N. & Nakashima, T. (1997). Cold tolerance and preconditioning of infective juveniles of
Steinernema kushidai (Nematoda: Steinernematidae). Nematologica (Netherlands).
22
Olafsson, E. (1995). Meiobenthos in mangrove areas in eastern Africa with emphasis on assemblage
structure of free-living marine nematodes. Hydrobiologia 312, 47-57.
Onkendi, E.M., Kariuki, G.M., Marais, M. & Moleleki, L.N. (2014). The threat of root-knot nematodes
(Meloidogyne spp.) in Africa: a review. Plant Pathology 63, 727-737.
Orion, D. & Kritzman, G. (2001). A role of the gelatinous matrix in the resistance of root-knot nematode
(Meloidogyne spp.) eggs to microorganisms. Journal of Nematology 33, 203.
Perry, R.N. (1989). Dormancy and hatching of nematode eggs. Parasitology Today 5, 377-383.
Perry, R.N. (2002). Hatching. The biology of nematodes 6, 147-169.
Perry, R.N. (2011). Understanding the survival strategies of nematodes. Animal science reviews, 99-104.
Perry, R.N., Ehlers, R.U. & Glazer, I. (2012). A realistic appraisal of methods to enhance desiccation
tolerance of entomopathogenic nematodes. Journal of Nematology 44, 185-190.
Perry, R.N. & Moens, M. (2011). Survival of parasitic nematodes outside the host. In: Perry, R.N. &
Wharton, D.A. (Eds). Molecular and Physiolgical Basis of Nematode Survival. UK, CAB
International, pp. 1-27.
Ploeg, A.T. & Maris, P.C. (1999). Effects of temperature on the duration of the life cycle of a
Meloidogyne incognita population. Nematology 1, 389-393.
Preston, C.M. & Bird, A.F. (1987). Physiological and morphological changes associated with recovery
from anabiosis in the dauer larva of the nematode Anguina agrotis. Parasitology 95, 125-133.
Prot, J.C. (1978). Influence of concentration gradients of salts on the movement of second stage juveniles
of Meloidogyne javanica. Revue de Nématologie (French) 1, 21-26.
Pye, A.E. & Burman, M. (1981). Neoaplectana carpocapsae: Nematode accumulations on chemical and
bacterial gradients. Experimental Parasitology 51, 13-20.
Qiu, L. & Bedding, R. (1999). Low temperature induced cryoprotectant synthesis by the infective
juvenniles of Steinernema carpocapsae: biological significance and mechanisms involved. Cryo-
letters 20, 393-404.
23
Raymond, M.R. & Wharton, D.A. (2013). The ability of the Antarctic nematode Panagrolaimus davidi to
survive intracellular freezing is dependent upon nutritional status. Journal of Comparative
Physiology B-Biochemical Systemic and Environmental Physiology 183, 181-188.
Riddle, D.L. & Bird, A.F. (1985). Responses of the plant parasitic nematodes Rotylenchulus reniformis,
Anguina agrostis and Meloidogyne javanica to chemical attractants. Parasitology 91, 185-195.
Salinas-Flores, L., Adams, S.L., Wharton, D.A., Downes, M.F. & Lim, M.H. (2008). Survival of Pacific
oyster, Crassostrea gigas oocytes in relation to intracellular ice formation. Cryobiology 56, 28-
35.
Schmitz, B., Burgermeister, W. & Braasch, H. (1998). Molecular genetic classification of central
european Meloidogyne chitwoodi and M. fallax populations. Nachrichtenblatt des Deutschen
Pflanzenschutzdienstes 50, 310-317.
Searcy, D.G., Kisiel, M.J. & Zuckerman, B.M. (1976). Age-related increase of cuticle permeability in the
nematode Caenorhabditis briggsae. Experimental aging research 2, 293-301.
Steiner, G. & Albin, F.E. (1946). Resuscitation of the nematode Tylenchus polyhypnus n. sp., after almost
39 years' dormancy. Journal of the Washington Academy of Sciences 36, 97-99.
Stiernagle, T. (2006). Maintenance of C. elegans (February 11, 2006), WormBook, ed. The C. elegans
Research Community, WormBook, doi/10.1895/wormbook. 1.101. 1. The C. elegans Research
Community, .
Thompson, J.M. & Tylka, G.L. (1997). Differences in hatching of Heterodera glycines egg-mass and
encysted eggs in vitro. Journal of Nematology 29, 315.
Turner, S.J. & Rowe, J.A. (2006). Cyst nematodes. In: Perry, R. & Moens, M. (Eds). Plant nematology.
UK, CAB International, pp. 91-122.
Tzortzakakis, E.A. & Trudgill, D.L. (2005). A comparative study of the thermal time requirements for
embryogenesis in Meloidogyne javanica and M. incognita. Nematology 7, 313-316.
Viaene, N., Wiseborn, D.B. & Karssen, G. (2007). First report of the root-knot nematode Meloidogyne
minor on turfgrass in Belgium. Plant Disease 91, 908-908.
24
Viglierchio, D.R., Croli, N.A. & Gortz, J.H. (1969). The physiological response of nematodes to osmotic
stress and an osmotic treatment for separating nematodes. Nematologica 15, 15-21.
Waeyenberge, L. & Moens, M. (2001). Meloidogyne chilwoodi and M. fallax in Belgium. Nematologia
Mediterranea 29, 91-98.
Wallace, H.R. (1971). The influence of temperature on embryonic development and hatch in Meloidogyne
javanica. Nematologica 17, 179-186.
Wesemael, W.M.L. & Moens, M. (2008). Quality damage on carrots (Daucus carota L.) caused by the
root-knot nematode Meloidogyne chitwoodi. Nematology 10, 261-270.
Wesemael, W.M.L., Perry, R.N. & Moens, M. (2006). The influence of root diffusate and host age on
hatching of the root-knot nematodes, Meloidogyne chitwoodi and M. fallax. Nematology 8, 895-
902.
Wesemael, W.M.L., Viaene, N. & Moens, M. (2011). Root-knot nematodes (Meloidogyne spp.) in
Europe. Nematology 13, 3-16.
Wharton, D. & Ferns, D. (1995). Survival of intracellular freezing by the Antarctic nematode
Panagrolaimus davidi. Journal of experimental biology 198, 1381-1387.
Wharton, D.A. (1980). Nematode egg-shells. Parasitology 81, 447-463.
Wharton, D.A. (1994). Freezing avoidance in the eggs of the Antarctic nematode Panagrolaimus davidi.
Fundam. Appl. Nematol 17, 239-243.
Wharton, D.A. (2002). Life at the limits: organisms in extreme environments. Cambridge university press
Cambridge 14, 427-431.
Wharton, D.A. (2003). The environmental physiology of Antarctic terrestrial nematodes: a review.
Journal of Comparative Physiology B 173, 621-628.
Wharton, D.A. (2004). Survival strategies. In: Gaugler, R. & Bilgrami, A.L. (Eds). Nematode behaviour.
Oxfordshire & Cambridge, CAB International, pp. 371-399.
25
Wharton, D.A. (2011). Cold tolerance. In: Perry, R.N. & Wharton, D.A. (Eds). Molecular and
physiological basis of nematode survival. CABI Publishing, Wallingford. UK, CAB International,
pp. 182-204.
Wharton, D.A. & Barclay, S. (1993). Anhydrobiosis in the free-living antarctic nematode Panagrolaimus
davidi (Nematoda: Rhabditida). Fundamental and Applied Nematology 16, 17-22.
Wharton, D.A., Downes, M.F., Goodall, G. & Marshall, C.J. (2005). Freezing and cryoprotective
dehydration in an Antarctic nematode (Panagrolaimus davidi) visualised using a freeze
substitution technique. Cryobiology 50, 21-28.
Wharton, D.A., Goodall, G. & Marshall, C.J. (2003). Freezing survival and cryoprotective dehydration as
cold tolerance mechanisms in the Antarctic nematode Panagrolaimus davidi. Journal of
experimental biology 206, 215-221.
Wharton, D.A., Judge, K.F. & Worland, M.R. (2000). Cold acclimation and cryoprotectants in a freeze-
tolerant Antarctic nematode Panagrolaimus davidi. Journal of Comparative Physiology B 170,
321-327.
Wharton, D.A., Perry, R.N. & Beane, J. (1993). The role of the eggshell in the cold tolerance mechanisms
of the unhatched juveniles of Globodera rostochiensis. Fundamental and Applied Nematology 16,
425-431.
Wharton, D.A., Preston, C.M., Barrett, J. & Perry, R.N. (1988). Changes in cuticular permeability
associated with recovery from anhydrobiosis in the plant parasitic nematode, Ditylenchus dipsaci.
Parasitology 97, 317-330.
Wharton, D.A. & Ramløv, H. (1995). Differential scanning calorimetry studies on the cysts of the potato-
cyst nematode Globodera rostochiensis during freezing and melting. The Journal of experimental
biology 198, 2551-2555.
Wieczorek, K., Elashry, A., Quentin, M., Grundler, F.M.W., Favery, B., Seifert, G.J. & Bohlmann, H.
(2014). A distinct role of pectate lyases in the formation of feeding structures induced by cyst and
root-knot nematodes. Molecular Plant-Microbe Interactions 27, 901-912.
26
Willmer, P., Stone, G. & Johnston, I. (2005). Environmental physiology of animals. John Wiley & Sons,
pp. 727.
Womersley, C. (1978). A comparison of the rate of drying of four nematode species using a liquid
paraffin technique. Annals of Applied Biology 90, 401-405.
Wright, D.J. (2004). Osmoregulatory and excretory behaviour. In: Gaugler, R. & Bilgrami, A.L. (Eds).
Nematode behaviour. UK, CAB International, pp. 177-196.
Wright, D.J. & Perry, R.N. (2006). Reproduction, physiology and biochemistry. In: Perry, R.N. & Moens,
M. (Eds). Plant nematology. 1st ed. UK, CAB International, pp. 187-209.
Wyss, U., Grundler, F.M.W. & Munch, A. (1992). The Parasitic Behavior of 2nd Stage Juveniles of
Meloidogyne incognita in Roots of Arabidopsis thaliana. Nematologica 38, 98-111.
Yeon, I.K., Kim, D.G. & Park, S.D. (2003). Soil temperature and egg mass formation by Meloidogyne
arenaria on oriental melon (Cucumis melo L.). Nematology 5, 721-725.
27
Part D: Addendum
Table 1. Time schedule and expected deliverables
Tasks Sept Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep
Collection,
reading and writing of
relevant
literatures on
research topics
Submission
of literatures
Lab works: Nematode
culture
Egg mass
collection
Adaptability testing
Data
analysis
Thesis
writing
Thesis defence