Phosphorus mobilization and uptake in mycorrhizal rice
(Oryza sativa L.) plants under flooded and non-flooded conditions
Roghieh HAJIBOLAND, Naser ALIASGHARZAD and Robabeh BARZEGHAR
ABSTRACT
Phosphorus (P) deficiency severely limits rice production in the world. Colonization of
plant root with arbuscular mycorrhizal fungi (AMF) may have a considerable consequence for
P uptake and plant growth. In contrast to other crop species, there is little experimental
evidence about the role of mycorrhizal colonization in lowland rice plants. This study was
undertaken to examine whether inoculation of rice plants can contribute in the
mobilization and uptake of insoluble P form. In addition, an attempt was made to compare
flooded plants with non-flooded ones in their mycorrhizal responsiveness. In one
experiment, insoluble P was supplied for plants inoculated either with Glomus mosseae or
Glomus intraradices, then growth and P uptake was determined. Results showed that
colonization with AMF significantly improved uptake of P derived from insoluble P source.
In other experiment, rice plants were inoculated with Glomus mosseae or Glomus
intraradices in non-flooded nurseries and then transplanted either to flooded or
non-flooded conditions. Root colonization by AMF was decreased due to flooding conditions
from 43% to 27%. Nevertheless, the plant growth responded positively (117% increase) to
inoculation when grown at flooded conditions, while dry matter of non-flooded plants was
diminished up to 64% by inoculation. Mycorrhizal colonization had also a significant
contribution in the uptake of P and K in flooded but not in non-flooded plants.
Key words: Glomus mosseae, Glomus intraradices, lowland rice, Oryza sativa, flooding
IZVLEČEK
MOBILIZACIJA IN PRIVZEM FOSFORJA V RIŽU (Oriza sativa L.) V PRISOTNOSTI
MIKORIZNIH GLIV S POPLAVNIM NAMAKANJEM IN BREZ LE-TEGA
Pomanjkanje fosforja (P) omejuje svetovno pridelavo riža. Naselitev rastlinskih
korenin z arbuskularnimi mikoriznimi glivami (AMF) bi lahko pomembno vplivala na privzem P
in rast rastlin. Poskusni podatki o vlogi mikorizne kolonizacije riževih rastlin so v
primerjavi z nekaterimi drugimi vrstami rastlin redki. Ta raziskava je bila zastavljena,
da bi proučili, ali inokulacija korenin riža z mikoriznimi glivami vpliva na
mobilizacijo in privzem netopne oblike P. Mikorizna odzivnost je bila preizkušena v
razmerah z in brez uporabe poplavnega namakanja. Netopna oblika P je bila dodana
rastlinam, inokuliranim z Glomus mosseae ali Glomus intraradices, opazovana je bila rast
rastlin in privzem P. Naselitev riževih korenin z AMF je vplivala na povečan privzem P
iz netopnega vira tega elementa. V drugem poskusu so bile rastline inokulirane z istima
vrstama mikoriznih gliv v nepoplavnih razmerah in nato presajene v poplavne in nepoplavne
razmere. Naselitev korenin z AMF se je v poplavnih razmerah znižala s 43% na 27%. Kljub
temu je bil odziv rastlin na inokulacijo in izpostavitev poplavnim razmeram pozitiven,
rast se je povečala za 117%, medtem ko se je suha snov rastlin iz nepoplavnih razmer
zmanjšala za 64%. Inokulacija z mikoriznimi glivami je prav tako pomembno vplivala na
privzem P in K v poplavnih razmerah, tega vpliva pa ni bilo mogoče zaznati pri rastlinah
v nepoplavnih razmerah.
Ključne besede: Glomus mosseae, Glomus intraradices, riž, Oryza sativa, poplavljanje
The first record of Aphidius ervi Haliday in Slovenia
Katarina KOS, Željko TOMANOVIĆ, Helena ROJHT, Stanislav TRDAN
ABSTRACT
In 2008, a lucerne aphid parasitoid Aphidius ervi Haliday was first recorded in
Slovenia. This oligophagous parasitoid is used as biological control agent against bigger
aphid species. By sampling aphid mummies on different locations in Slovenia in 2008, we
found parasitoid Aphidius ervi on nine host plants (corn, pea, alfalfa, red clover, winter
wheat, oat, onion, potato and winter barley). Among 1812 primary parasitoids found in
Slovenia in 2008, there were 46 individuals of Aphidius ervi; 21 male and 25 female
parasitoids. In the present paper description of the species, its geographic distribution
and host plant-aphid-parasitoid associations are given.
Keywords: Aphidius ervi, parasitoid, first record, biological control, Slovenia
IZVLEČEK
PRVA NAJDBA PARAZITOIDA Aphidius ervi Haliday V SLOVENIJI
V letu 2008 smo v Sloveniji prvič ugotovili zastopanost parazitoida Aphidius ervi
Haliday, ki parazitira zlasti listne uši na metuljnicah (Fabaceae). Ta oligofagni
parazitoid se uporablja kot biotični agens večjih vrst listnih uši. Parazitoida
Aphidius ervi smo v letu 2008 našli na 9 gostiteljskih rastlinah (koruza, grah, lucerna,
črna detelja, ozimna pšenica, oves, čebula, krompir in ozimni ječmen) v Sloveniji, in
sicer med vzorčenjem ušjih mumij. V letu 2008 smo nabrali 1812 primarnih parazitoidov,
med njimi je bilo 46 osebkov vrste Aphidius ervi; 21 je bilo samcev in 25 samic. V
prispevku je opisana vrsta, njena geografska razširjenost in povezava med gostiteljsko
rastlino, ušjo ter parazitoidom.
Ključne besede: Aphidius ervi, parazitoid, prva najdba, biotično varstvo rastlin,
Slovenija
.
Effect of preceding crops on the winter cereal
productivity and diseases incidence
Regina SKUODIENE, Rita NEKROŠIENE
ABSTRACT
Experiments were carried out in the Vežaičiai Branch of the Lithuanian Institute of
Agriculture (West Lithuania region) in 2002-2005. The aim of this research was to estimate
the ecological significance of perennial legumes used as green manure for the biological
properties of triticale and rye and for diseases resistance. Residues of the perennial
grasses tested and ploughed-in aftermath contributed different contents of nitrogen to the
soil. The highest content of nitrogen was contributed to the soil with red clover residues
and aftermath. Residues of white clover and aftermath ploughed in as green manure
determined more favourable soil properties. This had a positive effect on the formation of
biological parameters of cereals grown after white clover, which made it possible without
mineral and organic fertilisers to produce on average 3.88 t ha-1 of triticale grain and
3.82 t ha-1 of rye grain, or by 1.09 and 0.28 t ha-1 more compared with their growing
after red clover managed in the same way as white clover. Different growing conditions of
winter cereals, i.e. different preceding crops, had a significant effect on the occurrence
of scald and septoriosis.
Key words: preceding crops, winter cereal, productivity, yield forming indicators,
diseases
IZVLEČEK
VPLIV PREDHODNIH POSEVKOV NA PRIDELEK TER POJAVNOST BOLEZNI PRI OZIMNIH
ŽITIH
Poskusi so bili opravljeni v Vežaičiai Branch na Lithuanian Institute of Agriculture
v obdobju od leta 2002 do 2005. Namen raziskave je bil oceniti ekološki pomen trajnih
metuljnic, uporabljenih za zeleno gnojenje, na odpornost proti boleznim ter na biološke
lastnosti tritikale in rži. Zaorani ostanki zelenih delov preizkušanih metuljnic so
imeli različne vplive na vsebnost dušika v tleh. K najvišji vsebnosti dušika so
prispevali ostanki rdeče detelje, zaorani ostanki bele detelje pa so imeli ugodnejše
učinke na lastnosti tal. Izboljšane talne lastnosti so pozitivno vplivale na parametre
rasti, ki so omogočili pridelek 3,88 t ha-1 zrnja tritikale in 3,82 t ha-1 zrnja rži
brez uporabe mineralnih ali drugih organskih gnojil. Ko je bil predhodni posevek rdeča
detelja, je bil pridelek tritikale manjši za 1,09 t ha-1, pridelek rži pa za 0,28 t ha-1
manjši v primerjavi s pridelkom po zelenem gnojenju z belo deteljo. Različni predhodni
posevki so imeli pomemben vpliv na pojavnost ožiga in listne pegavosti.
Ključne besede: predhodni posevki, ozimna žita, pridelek, bolezni
Heterorhabditis bacteriophora (Poinar) - the
first member from Heterorhabditidae family in Slovenia
Žiga LAZNIK, Tímea TÓTH, Tamás LAKATOS, Stanislav TRDAN
ABSTRACT
In August 2008, we examined 95 soil samples for the occurrence of entomopathogenic
nematodes in eastern part of Slovenia. 11 samples from 9 different locations were positive
to entomopathogenic nematodes, but to this time only sample D54 was analysed. This soil
sample was collected in Dravograd. Genetic studies proved that the nematode species in
this sample was Heterorhabditis bacteriophora. This is the first record of Heterorhabditis
nematode in Slovenia. Until now we confirmed the presence of four entomopathogenic
nematode species in Slovenia; Steinernema affine, Steinernema carpocapsae, Steinernema
feltiae and Steinernema kraussei. We expect that in Slovenia the use of these biological
agents against insect pests will become important alternative to insecticides as it is
known in many other countries of the world.
Key words: biological control, entomopathogenic nematodes, indigenous species,
Slovenia, Heterorhabditis bacteriophora, Heterorhabditidae, first record
IZVLEČEK
ENTOMOPATOGENA OGORČICA Heterorhabditis bacteriophora (Poinar) - PRVI
PREDSTAVNIK IZ DRUŽINE HETERORHABDITIDAE, NAJDEN V SLOVENIJI
V avgustu 2008 smo preučili 95 talnih vzorcev, da bi ugotovili zastopanost
entomopatogenih ogorčic v vzhodnem delu Slovenije. 11 vzorcev z devetih različnih
lokacij je bilo pozitivnih na zastopanost entomopatogenih ogorčic. Doslej smo analizirali
le vzorec D54, ki je bil odvzet blizu Dravograda. Genetska analiza je potrdila, da gre za
vrsto Heterorhabditis bacteriophora. Gre za prvo najdbo ogorčice iz rodu Heterorhabditis
v Sloveniji. Doslej smo v Sloveniji potrdili zastopanost 4 vrst entomopatogenih ogorčic,
in sicer: Steinernema affine, Steinernema carpocapsae, Steinernema feltiae in Steinernema
kraussei. Pričakujemo, da bo v Sloveniji uporaba omenjenih naravnih sovražnikov
škodljivih žuželk postala pomembna alternativa insekticidom, kar je sicer že znano v
številnih drugih državah sveta.
Ključne besede: biotično varstvo, entomopatogene ogorčice, domorodna vrsta,
Slovenija, Heterorhabditis bacteriophora, Heterorhabditidae, prva najdba
Aphid population in watermelon (Citrullus lanatus
Thunb.) production
Katja ŽANIĆ, Dean BAN, Marisa ŠKALJAC, Gvozden DUMIČIĆ, Smiljana GORETA BAN,
Dragan ŽNIDARČIČ
ABSTRACT
The aim of this study was to compare the effect of PE black mulch with bare soil and
hay cover against winged aphid number. In order to create management strategy in
watermelon, flight dynamics of aphid population was recorded. The field experiment was set
up as a randomized block design in three replications at Pula in Mediterranean region of
Croatia. Aphids were collected weekly using yellow water metal traps. There were six
sampling dates starting from 19 May until mulch was covered by plant canopy. We found
significant difference in aphid number among the sampling dates as a result of their
population dynamics on watermelon. The catches of two assessments in the second half of
May were more numerous than during assessments in June. The flight maximum was recorded on
26 May and the population density significantly decreased from 9 June. There was not much
effect of mulch on aphid number. However, at the peak of aphid population hay cover
attracted 13% (26 May) and 18% (2 June) more aphids compared to bare soil.
Key words: Aphidae, watermelon, Citrullus lanatus, PE black film, hay mulch
IZVLEČEK
LISTNE UŠI NA LUBENICAH (Citrullus lanatus Thunb.)
Cilj naše raziskave je bil ugotoviti, kako PE črna folija v primerjavi z golimi tlemi
in tlemi, prekritimi s senom, vpliva na razširjenost listnih uši na lubenicah. Tako smo
z ugotavljanjem številčnega stanja uši želeli prilagoditi tehnolgijo gojenja lubenic v
boju proti tem škodljivcem. Poljski poskus, ki je bil leta 2008 zasnovan po metodi
naključnih blokov v treh ponovitvah, je bil postavljen v okolci Pulja v primorskem delu
Hrvaške. Prisotnost uši smo s preštevanjem na rumenih kovinskih vabah ugotavljali vsak
teden. Od 19. maja do trenutka, ko so listi lubenic prekrili tla, smo opravili šest
preštevanj. Med posameznimi datumi smo ugotovili značilno razliko med številom uši na
vabah, ki je bila posledica njihove populacijske dinamike na rastlinah. Število uši v
dveh preštevanjih v drugi polovici maja je bilo znato večje od števila uši naštetih v
juniju. Največji nalet uši je bil ugotovljen 26. maja. Njihova razširjenost pa se je
značilno zmanjšala do 9. junija. Način zastiranja tal ni statistično značilno vplival
na razširjenost uši. Poudariti pa je treba, da je na vrhuncu prisotnosti uši senena
zastirka privabila 13 % (26. maja) oz. 18 % (2. junija) več uši, kot smo jih našteli v
obravnavanjih na golih tleh.
Ključne besede: Aphidae, lubenice, Citrullus lanatus, PE črna folija, senena zastirka
Changes in floristic composition over three years of
Ljubljana marsh grassland in relation to cutting and fertilising management
Matej VIDRIH, Jure ČOP, Stanislav TRDAN, Klemen ELER
ABSTRACT
A research in Ljubljana marsh was conducted from 2004 to 2006 with the aim to determine
how the regime of cutting and fertiliser application over several years influences on the
floristic composition of meadow sward. Field sampling plots in split-plot design with four
replications were set up on two different types of grassland, one belonging to
Arrhenatherion (sampling plot T1), the other to Molinion alliances (sampling plot T2) in
1999. The main plots represented the frequency of 4 cutting regimes (2 cuts with normal
and delayed first one, 3 and 4 cuts per year) and sub-plots represented the fertiliser
regime (no fertiliser, PK and NPK fertiliser with two different amounts of N). After five
years, the cutting, and especially fertiliser application, significantly altered the
floristic composition. In floristic composition of Arrhenatherion plot more frequent
cutting in combination with higher amount of N fertilisation increased the proportion of
grasses (92.7 % on a fresh matter basis). This was mostly observed in 2004. Legumes
proportion (15.4 %) increased mainly on plots where PK fertiliser was used and a first cut
was retarded. When N fertiliser was used on Molinion plot in all treatments with cutting
herbs (forbs) increased their proportion up to 65 % in average. The proportion of legumes
in sward of this plot was neglecteable that's way treatments did not have any special
effect on them.
Key words: Ljubljana marsh, grassland, cutting, fertilising, floristic composition,
biomass
IZVLEČEK
SPREMEMBE V FLORISTIČNI SESTAVI RUŠE LJUBLJANSKEGA BARJA SKOZI TRI
LETA V ODVISNOSTI OD ČASA KOŠNJE IN INTENZIVNOSTI GNOJENJA
Na Ljubljanskem barju smo v obdobju 2004-2006 opravili raziskavo, s katero smo želeli
ugotoviti, kako vplivata število košenj in gnojenje skozi daljše obdobje na
floristično sestavo ruše. Travniška poskusa v split-plot zasnovi s štirimi ponovitvami
sta bila zasnovana na dveh tipih poskusnih ploskev, ki pripadata zvezama Arrhenatherion in
Molinion v letu 1999. Glavne parcele so predstavljale štiri režime pogostnosti košnje
(2-kosna raba z zapoznelo in standardno prvo košnjo, 3-kosna in 4-kosna raba), podparcele
pa način gnojenja (negnojeno, gnojeno z gnojili PK in NPK, gnojeno z dvema različnima
odmerkoma N). Po petih letih sta košnja in predvsem gnojenje zelo spremenili videz
travišča in vplivala na floristične karakteristike travne ruše. V travni ruši
poskusnih ploskev zveze Arrhenatherion je pogostejša košnja v kombinaciji z večjim
odmerkom dušika vplivala na večji delež trav (92,7 % v svežem zelinju). Ta sprememba
je bila najbolj izražena v letu 2004. Delež mase metuljnic (15,4 %) se je najbolj
povečal po gnojenju s PK in zapoznelo prvo košnjo. Na poskusni parceli zveze Molinion se
je najbolj povečal delež zeli (največ 65 %), in sicer v vseh postopkih košnje ter
tedaj, kadar je bil uporabljen dušik. Delež metuljnic v tej ruši je bil zanemarljiv.
Ključne besede: Ljubljansko barje, travinje, košnja, gnojenje, floristična sestava,
biomasa
Fosfor v zemlji in zelinju kraškega pašnika
Matej VIDRIH, Anton VIDRIH, Milan POGAČNIK, Drago KOMPAN
IZVLEČEK
Predstavljeni so rezultati 7-letne raziskave o vplivu dodanega P na njegovo dostopnost
v tleh, na vsebnost P v zelinju kraškega pašnika in na povečanje mase razpoložljivega
zelinja pri stopnjujočem se odmerku uporabljenega gnojila (0, 90, 270 in 540 kg P2O5 ha-1
skupno v 3 letih). Koncentracija dostopnega P v tleh je bila v obravnavanju nizek odmerek
(30 kg P2O5 ha-1 letno) večja za 2,4 mg P2O5 100 g-1 tal od kontrolnega obravnavanja. S
trikrat večjim odmerkom gnojila je bila vsebnost P v tleh povečana za 4,4-krat.
Vzorčenje zemlje do dveh globin (0 - 3 cm in 3 - 6 cm) je pokazalo, da je večji del
razpoložljivega P za rast rastlin v vrhnji, zelo plitvi plasti zemlje. V petih rastnih
sezonah po zadnjem gnojenju s P se je zmanjšala koncentracija dostopnega P v tleh od 0,4
mg do 3,6 mg P2O5 100 g-1 tal, odvisno od skupno uporabljenega gnojila. Zaradi izredne
siromašnosti zemlje kraškega pašnika s P, je tudi njegova vsebnost v zelinju ruše zelo
nizka. Zadošča le za polovično pokritje potreb pašnih živali po tej rudnini, zato je
povečanje vsebnosti P v zelinju pri gnojenju s fosfati pomembnejše od povečanja
pridelovalne zmogljivosti zemljišča. Z letnim odmerkom 90 kg P2O5 ha-1 se je v treh
rastnih sezonah v povprečnem vzorcu zelinja koncentracija P povečala na 2,1 g P kg-1 SS.
Uporabljen P je imel na maso zelinja razpoložljivega za pašo in na delež
izkoriščenosti ruše majhen vpliv, najverjetneje zaradi kisle reakcije tal in počasnega
izboljšanja floristične sestave ruše.
Ključne besede: fosfor, kraški pašnik, gnojenje, tla, zelinje
ABSTRACT
PHOSPHORUS IN THE SOIL AND IN THE HERBAGE OF THE KARST PASTURE
The results of P fertilization on karst pasture in a 7-year study are discussed. The
changes of P availability for plants, the content of P in herbage and the yield increase
at different rates of applied fertilizer (0, 90, 270 and 540 kg P2O5 ha-1 - total in 3
years) were measured. In treatment with low rate of P (30 kg P2O5 ha-1 year-1), the
concentration of available P in soil was increased for 40 %. At three times higher rate of
applied P, the content in soil was increased for 4,4 fold. The most of available P was
found in top layer of soil as show the results of soil sampling at two depths (0 - 3 cm
and 3 - 6 cm). The contentration of P in soil decreased during five growing seasons for
0.4 mg to 3.6 mg P2O5 100 g-1 of soil, depending on rate of applied fertiliser. Because
the soils of karst pasture are very poor on P, the concentration of P in herbage is very
low too. Only one half of the animal's need for P can be covered this way. The increase of
P concentration in herbage as a result of applied P is more important than the increase of
the yield. At annual rate of 90 kg P2O5 ha-1 the average concentration of P in herbage was
2.1 g P kg-1 of DM. The effect of applied P on the yield of available and used herbage by
grazing animals was small, due to low soil pH and slow improvement in floristic
composition of the sward.
Key words: phosphorus, karst pasture, fertilizing, soils, herbage
Primerjava lastnosti polipropilenskih vlaken,
namenjenih za izdelavo vrtnarskih vlaknovin
Andrej DEMŠAR, Dragan ŽNIDARČIČ, Diana GREGOR-SVETEC
IZVLEČEK
V intenzivnem vrtnarstvu se za vzgojo sadik in pridelavo vrtnin v vseh letnih časih
uporablja različne oblike zavarovanega prostora. Najenostavnejša in najcenejša oblika
zavarovanega prostora je neposredno prekrivanje rastlin z agrotekstilijami. Agrotekstilije
so vlaknovine, izdelane iz tekstilnih vlaken, ki so navadno kemičnega izvora. Od
agrotekstilij namenjenih za prekrivanje vrtnin, se zahtevajo primerna trdnost in dobre
prepustne lastnosti, ki se pod vplivom vremenskih sprememb ne smejo bistveno poslabšati.
Lastnosti agrotekstilij so odvisne od vlaken, iz katerih so agrotekstilje izdelane, ter od
postopka in pogojev izdelave. Namen raziskave je bil analizirati dva tipa polipropilenskih
(PP) vlaken (FiberVisionsR HY-Comfort in UV-stabilizirana PP vlakna TrevonR), namenjenih
za izdelavo vrtnarskih vlaknovin, primerjati rezultate z deklariranimi vrednostmi in
predstaviti nekatere metode analize tekstilnih vlaken. Raziskava je pokazala, da prihaja
med izmerjenimi in deklariranimi vrednostmi pri nekaterih lastnostih primerjanih vlaken do
določenih razlik in da sta si preučevana tipa PP vlaken različna v tekstilno-mehanskih
in strukturnih lastnostih.
Ključne besede: agrotekstil, polipropilenska vlakna, vlaknovina, mehanske lastnosti
ABSTRACT
THE COMPARISON OF PROPERTIES OF POLYPROPYLENE FIBRES INTENDED FOR THE
PRODUCTION OF AGROTEXTILES
In the intensive horticulture various ways of protected area are used for the growth of
seedlings and the cultivation of vegetables in all seasons. The easiest and the cheapest
form of protected area is agrotextile which can be laid directly over field crops.
Agrotextiles are nonwovens which are manufactured from textile fibers which are usually of
chemichal origin. Textiles, used as a agrotextiles require suitable tensile strenght, and
good permeability characteristics with no significant deterioration under the influence of
weather changes. Properties of agrotextiles depend on the fibers made of and on the type
and conditions of production. The aim of research was to analyse two types of
polypropylene (PP) fibers (FiberVisionsR HY-Comfort and UV-stabilised PP fibers TrevonR)
which are used for the production of agrotextiles and to compare the results with the
declared properties and to present some methods for the analysis of the textile fibers.
The research showed that there is a difference between measured and declared properties
and that two types of PP fibers are different regarding textile-mechanical and structural
properties.
Key words: agrotextile, polypropylene fibers, nonwovens, mechanical properties
Vpliv agroekoloških razmer na ekonomsko upravičenost
ekološkega pridelovanja solate (Lactuca sativa L.)
Milan OPLANIĆ, Dean BAN, Stanislav TRDAN, Dragan ŽNIDARČIČ
IZVLEČEK
Cilj raziskave je bil primerjati ekonomsko uspešnost gojenja solate v konvencionalnem
in ekološkem načinu pridelave v celinskem in sredozemskem delu Republike Hrvaške. V
letih 2002 in 2003 je bil poskus postavljen na družinskih kmetijah v okolici Pulja
(sredozemsko območje) in v okolici kraja Otočac (celinsko območje). Dobljeni rezultati
kažejo na to, da ima gojenje solate v ekološki pridelavi za posledico manjši pridelek,
kar je še bolj izrazito v celinskem podnebju. Da bi bila pridelava solate iz takega
načina gojenja ekonomsko opravičljiva, je treba zanjo doseči višjo prodajno ceno v
primerjavi s solato iz konvencionalne pridelave. Iz istega razloga bi morala biti tudi
prodajna cena ekološko pridelane solate na celinskem območju višja kot cena solate,
pridelane ob morju.
Ključne besede: konvencionaln pridelava, ekološka pridelava, solata, Lactuca sativa,
Hrvaška
ABSTRACT
THE IMPACT OF AGROECOLOGICAL CONDITIONS ON ECOLOGICALLY SOUND AND
ECONOMICALLY VIABLE PRODUCTION OF LETTUCE (Lactuca sativa L.)
The aim of research was to compare the economic performance of growing lettuce in the
conventional and ecological crop management of production in the mainland and the
Mediterranian part of Croatia. In the years 2002 and 2003 the experiment was carried out
on family farms in the vicinity of Pula (the Mediterranian area) and in the vicinity of
Otočac (the mainland area). The obtained results show that the cultivation of lettuce in
the ecological crop management in lower yields, which is even more apparent in continental
climate. In order to justify the ecological crop management of lettuce economically, it is
essential to achieve a higher sales price in comparison with the lettuce cultivated
according to the conventional system. For that reason, the sales price of ecolgical grown
lettuce in the mainland should be higher than in the Mediterranean.
Key words: conventional crop management, integrated crop management, lettuce, Lactuca
sativa, Croatia
Vsebnost esencialnih maščobnih kislin v zelju (Brassica
oleracea L.)
Dragan ŽNIDARČIČ, Rajko VIDRIH
IZVLEČEK
Namen raziskave je bil preučiti in s prehranskega vidika ovrednotiti
maščobnokislinsko sestavo 12 kultivarjev zelja (Brassica oleraceae L.). Vzorce smo
homogenizirali in jim z liofilizacijo odstranili vodo. Maščobnokislinsko sestavo smo
določili z izolacijo metilnih estrov in z analizo na plinskem kromatografu. Iz rezultatov
je razvidno, da zelje vsebuje malo nasičenih maščobnih kislin. Analiza nenasičenih
maščobnih kislin kaže na to, da zelje v povprečju vsebuje 18,8 mg/100 g SS
?-linolenske, 17,1 mg/100 g SS linolne in 14,8 mg/100 g SS oleinske kisline. Zeljne glave
vsebujejo v največji meri ravno obe najpomembnejši esencialni maščobni kislini (n-6 in
n-3), kar zelju daje visoko prehransko vrednost. Vsebnost posameznih nenasičenih
maščobnih kislin se med kultivarji zelja značilno razlikuje. Največji delež
?-linolenske kisline ima cv. 'Maestro' (29,9 mg/100 g SS), linolna kislina je najbolj
zastopana v cv. 'Holandsko pozno zelje' (30,6 mg/100 g SS) in oleinska v cv. 'Galaxy'
(29,9 mg/100 g SS) in cv. 'Vestri' (26,1 mg/100 g SS).
Ključne besede: zelje, Brassica oleraceae, nasičene maščobne kisline, nenasičene
maščobne kisline
ABSTRACT
CONTENT OF ESSENTIAL FATTY ACIDS IN CABBAGE (Brassica oleracea
L.)
The main objectiv of research was to study and evaluate the composition of essential
fatty acids of 12 cultivars of cabbage (Brassica oleraceae L.). All samples were
homogenised and liophilised. The fatty acids content was determined by the extraction of
fatty acid methyl esters and analyses by means of gas chromatography. The obtained results
show that cabbage is not a good source of saturated fatty acids. The unsaturated fatty
acids in cabbage are composed of ?-linolenic acid (18.8 mg/100 g DW), linoleic acid (17.1
mg/100 g DW) and oleic acid (14.8 mg/100 g DW). The high content of both essential fatty
acids (n-6 and n-3) in cabbage heads contribute to their nutritional value. There are
significant differences between cabbage cultivars in the unsaturated fatty acid pattern.
Cv. 'Maestro' contains the highest part of ?-linolenic acid (29.9 mg/100 g DW). The
highest concentration of linoleic acid contains cv. 'Holandsko pozno zelje' (30.6 mg/100 g
DW) and the highest concentration of oleic acid contain cv. 'Galaxy' (29.9 mg/100 g DW)
and cv. 'Vestri' (26.1 mg/100 g DW).
Key words: cabagge, Brassica oleraceae, saturated fatty acids, unsaturated fatty acids
WOFOST: model za napovedovanje pridelka - 1. del
Tjaša POGAČAR, Lučka KAJFEŽ-BOGATAJ
IZVLEČEK
Model WOFOST je bil odgovor Alterre in centra Plant Research International (oboje
Wageningen, Nizozemska) na potrebe po agrometeorološkem simulacijskem modelu za 10-dnevno
kvantitativno napovedovanje pridelka na državni ali regionalni ravni in kvalitativni
monitoring pogojev za rast različnih poljščin za celotno EU. Celo družino modelov, v
katero spada tudi WOFOST, so razvijali v Wageningnu v šoli C. T. de Wita. Prvič je bil
dokumentiran leta 1986 (Wolf in sod.), njegov prvotni namen je bil preučevanje
potencialnega pridelka različnih poljščin v tropskih državah, s čimer so se ukvarjali
van Keulen, Wolf in van Diepen. Uspešne verzije WOFOST-a se že več kot 10 let
uporabljajo v različnih raziskavah. Različne aplikacije so bile prilagojene za analizo
tveganja pri pridelku, variabilnosti pridelka skozi leto, variabilnosti zaradi različnih
tipov tal ali zaradi raznovrstnih agrohidroloških pogojev in razlik med kultivarji,
relativne pomembnosti faktorjev, ki določajo rast, setvenih strategij, vplivov podnebnih
sprememb, kritičnih period za uporabo agrikulturne mehanizacije in drugega. Trenutno je
dostopna verzija WOFOST 7.1.2.
WOFOST je fizikalni model, ki razlaga rast pridelka na osnovi procesov, ki se dogajajo
v rastlini in upošteva, kako na te procese vplivajo okoljske razmere. Osnova za izračune
produkcije suhe snovi je stopnja asimilacije CO2 v rastlinski odeji, ki je odvisna od
absorbirane energije sevanja in je funkcija vpadajočega sevanja in listne površine
poljščine. Izbiramo lahko med potencialno in dejansko (omejena količina vode)
simulacijo. Meteorološke podatke moramo pripraviti v pravilnem formatu. WOFOST uporablja
vodno bilanco, ki v danem časovnem obdobju primerja količino vode, ki pride v koreninsko
cono, s tisto, ki gre iz nje, ter določi razliko med njima za spremembo vsebnosti vode v
tleh. Upošteva infiltracijo, evaporacijo, transpiracijo, perkolacijo in kapilarni dvig.
Pri tem se moramo zavedati, da model ni namenjen natančni fizični obdelavi gibanja vode
v tleh, temveč le oceni dostopnosti vode za rastlino. Vpiv hranil (dušik, fosfat in
kalij) na pridelek se računa na letnem nivoju na osnovi dela Janssena in sod. iz leta
1990. WOFOST izračuna fenološko fazo iz dnevne temperature in korekcijskega faktorja.
Temperaturne vsote, potrebne za doseganje določene faze, so določene v datotekah, ki
opisujejo posamezne poljščine. V posebnih prilogah k opisu modela si lahko natančno
preberemo vse o enačbah, ki jih model uporablja, o izračunih energije globalnega
obsevanja, Gaussovi integraciji, linearni interpolaciji z AFGEN funkcijo, določanju
datuma setve, CGMS (Crop Growth Monitoring System) bazi podatkov, uporabi meteoroloških
podatkov ter podatkov o poljščinah in tleh v CGMS-u.
Ključne besede: WOFOST, razvoj modela, vhodni podatki, vodna bilanca, pridelek, koruza
ABSTRACT
WOFOST: CROP GROWTH SIMULATION MODEL - 1ST PART
The WOFOST crop growth simulation model was selected, when the JRC (i.e. European
Commission) requested Alterra (formerly SC-DLO) and Plant Research International (formerly
AB-DLO) in Wageningen, The Netherlands, to develop, adapt and calibrate new or existing
agro-meteorological simulation models for 10-day routine quantitative forecasting of
national and regional yields and qualitative monitoring of the growth conditions for the
whole EU for different kinds of crops. WOFOST is a member of the family of crop growth
models developed in Wageningen by the school of C.T. de Wit. The first WOFOST model has
been documented by Wolf et al. (1986) and it was originally developed to assess yield
potential of various annual crops in tropical countries (van Keulen & Wolf, 1986; van
Diepen et al., 1988; van Keulen & van Diepen, 1990). Over the last ten years, the
successive WOFOST versions have been used in many studies. WOFOST has been applied as a
tool for the analysis of yield risk and inter-annual yield variability, of yield
variability over soil types, or over a range of agro hydrological conditions, of
differences between cultivars, of relative importance of growth determining factors, of
sowing strategies, effects of climate change, critical periods for use of agricultural
machinery and others. Recently, the version WOFOST 7.1.2. is in use.
WOFOST is a mechanistic model that explains crop growth on the basis of the underlying
processes, such as photosynthesis, respiration and how these processes are influenced by
environmental conditions. Crop growth depends on the daily net assimilation, which on its
turn depends on the intercepted light. The intercepted light is determined by the level of
incoming radiation and the leaf area of the crop. We can choose between potential and
water-limited simulation. We have to prepare meteorological data in the requested format.
WOFOST uses a water balance, which compares for a given period of time, incoming water
in the rooted zone with outgoing water and quantifies the difference between the two as a
change in the stored soil moisture amount. Several processes are included: infiltration,
evaporation, transpiration, percolation and capillary rise. We have to keep in mind that
the model is not meant to calculate the water balance in first place. The procedure which
calculates the nutrient requirements is based on the work of Janssen et al. (1990).
Phenological phase is calculated from daily temperature and correction factor. Temperature
sums needed for each phase are determined in crop files. Appendices to the model
description include equations, description of the global radiation calculation, Gauss
integration, linear interpolation with AFGEN function, sowing date determination, CGMS
(Crop Growth Monitoring System) data base, use of meteorological, crop and soil data in
CGMS.
Key words: WOFOST, model development, input data, water balance, crop yield, maize
WOFOST: model za napovedovanje pridelka - 2. del
Tjaša POGAČAR, Lučka KAJFEŽ-BOGATAJ
IZVLEČEK
Model WOFOST (WOrld FOod STudy) je precej enostaven za prvo uporabo. Za nastavitve
imamo na voljo pet zavihkov: splošno, poljščina, vreme, tla, ponovitve. Izbiramo med
potencialno simulacijo, dejansko simulacijo pri omejeni količini vode in dejansko
simulacijo pri omejeni količini hranil. Za obravnavo izbrane poljščine moramo dobro
poznati njene karakteristike ali pa si izberemo poljščine, ki so že definirane v
modelu. Določamo tudi datum setve in žetve ali pa prepustimo modelu, da izbere
najprimernejša. Meteorološke podatke moramo za obravnavan kraj pripraviti v zahtevanem
formatu. Tudi podatki o različnih tipih tal so že pripravljeni, lahko pa dodamo svoje.
WOFOST nam med drugim izračuna fenološke faze, suho težo korenin, listov, stebel in
založnih organov, celotno nadzemsko produkcijo, žetveni indeks, evapo(transpi)racijo,
asimilacijo, bazalni metabolizem, globino dejanske koreninske cone, vsebnost vode v tleh
ter sušne in mokre dni.
Naši izračuni za primer koruze kažejo stanje sušnosti, kot je po izbranih letih od
2003 do 2006 tudi pričakovano - izrazito sušno leto 2003, sušnejše 2006, zmerno 2005
in precej mokro leto 2004. Razlike v vsebnosti vode v tleh se kažejo po koncu maja.
Najhitreje je koruza dozorela v najbolj sušnem letu 2003 in najpočasneje v najbolj
namočenem 2004. Vidimo lahko še, da na začetku rasti evaporacija iz tal prevladuje nad
transpiracijo, med glavno rastno sezono prevladuje transpiracija, na koncu pa zopet
evaporacija iz tal. Daleč najmanjša je produkcija leta 2003 zaradi precejšnih težav s
sušo, sledi leto 2006 in praktično enaka pridelka v letih 2004 in 2005, ko večjega
pomanjkanja dežja ni bilo.
Pokazali smo še, da je število sušnih dni precej različno pri različnih tipih tal.
Na tleh s slabo zadrževalno sposobnostjo je več sušnih let, kot na boljših tleh, v
splošnem pa so bila najbolj sušna leta 2001, 1992, 1971, 1988, 2003 in 1993 (izračuni
do leta 2005).
Ključne besede: WOFOST, napovedovanje pridelka, vhodni podatki, suša, rastlinska
produkcija
ABSTRACT
WOFOST: CROP GROWTH SIMULATION MODEL - 2ND PART
WOFOST (WOrld FOod STudy) model is with its user friendly preface very simple to use.
It has five tabs: general, crop, weather, soil and reruns, where we determine the
calculation parameters. The simulation can base on potential, water-limited or
nutrition-limited conditions. Crop parameters have to be quite well known or we can choose
pre-determined crop from the model, similar it is with the soil data. There is also
possible to set the date of sowing and harvesting (maturity), but we can let the model to
choose the more appropriate ones, which are based on meteorological conditions. The format
for meteorological data is determined, so we have to prepare them correctly. WOFOST model
calculates among others phenological stages, dry weight of roots, leaves, stems and
storage organs, total above ground production, harvesting index, evapo(transpi)ration,
assimilation, maintenance respiration, actual root zone depth, soil moisture and dry/wet
days.
Our calculations for maize (pre-defined) give us the estimation of the effect of
drought on crop yield for the period 2003-2006. Year 2003 was extremely dry, dry was also
2006, 2005 was moderate and 2004 was wet. Major differences in soil moisture between years
came out at the end of May. Maize reached maturity the earliest in 2003 and the latest in
2004. At the beginning of the growth season there is higher soil evaporation than
transpiration, in the middle is higher transpiration and at the end again soil
evaporation. Crop production is also depending on water conditions, so it is much smaller
in 2003, a bit bigger in 2006, in 2004 and 2005 it was quite the same - there were no
problems with the water shortage. We have also shown that the number of dry days strongly
depends on the soil type; there are much more dry days on the soil with low water holding
capacity. In general, the driest years were 2001, 1992, 1971, 1988, 2003 in 1993 (until
2005).
Key words: WOFOST, yield prediction, input data, drought, crop production
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