Kusuka kumagazini: No. 1 2014
Fania Zamalieva, Tatyana Zaitseva, Lyudmila Ryzhikh, Zifa Salikhova, Tatar Research Institute of Agriculture of the Russian Agricultural Academy
I-Fusarium wilt ithinta amazambane eTatarstan ngezikhathi ezithile, kodwa ukusabalala kwe-epiphytotic kwalesi sifo ngo-2011 kanye nokukhula kwayo eminyakeni eyalandela 2012-2013 kwenza kwaba nokwenzeka ukuthola izici ezintsha ekuhambeni kwayo, ulwazi olungasetshenziswa ukunciphisa ukulahleka kwezitshalo. Ukuxilongwa kwenziwa ngesisekelo seqoqo lezimpawu ezibonakalayo ezitshalweni zamazambane, izilimo eziyizigaxa, kanye nokusekelwe emiphumeleni yokuhlaziywa kokutheleleka okufihlekile kwezicubu ezivela ohlelweni lwe-vascular of stems nezilimo eziyizigaxa ngokusho kwendlela (i-Popkova K.V.), Shmyglya V.A., 1980). Isikhunta esisihlukanisile neziqu zamazambane kanye nezilimo eziyizigaxa ziyingxenye yohlobo lwe-Fusarium ngohlobo lwe-spore; ukuhlonzwa kwezinhlobo kuzokwenziwa maduze. Singaqaphela kuphela ukuthi lapho sithola ukutheleleka okucashile, sasivame ukubona ukwakheka kwe-mycelium emhlophe, isici se-Fusarium solana.
Ukuhlukanisa ukubola okomile, okwenzeka ngenxa ye-Fusarium wilt, ekuboleni okomile okuvamile, okwenzeka lapho i-Fusarium itheleleka ngenxeba, lesi sihloko sethula igama elicacisayo lokubola kwe-tuber okubangelwa i-Fusarium wilt - i-vascular fusarium yezilimo eziyizigaxa.
I-Fusarium wilt yamazambane yisifo esiyingozi; ayilimazi kuphela isivuno salo nyaka, kodwa futhi nasekukhiqizeni okulandelayo. Ngenxa yokudluliselwa kokutheleleka ngezilimo eziyizigaxa zembewu ezithintekayo yi-vascular fusarium ngendlela efihlekile, kungabangela ukuncipha kwezithombo kanye nokuvimbela ukukhula kwezitshalo esizukulwaneni esilandelayo. Ukuthuthukiswa kwe-Fusarium wilt, uma i-pathogen isivele yangena esitshalweni, kuncike kakhulu esimweni semvelo. Imithombo ye-fusarium ihlala ikhona enhlabathini futhi ubuthakathaka obuthile bezitshalo kanye nezimo ezivumayo zokukhula kwesikhunta (ukushintshana kwezikhathi ezimanzi nezomile emazingeni okushisa aphezulu) kuyadingeka ukuze ukhunta lungene esitshalweni. Yilezi zimo esizibone ngokwandayo eriphabhulikhi yethu eminyakeni yamuva nje.
Ukuqala kwe-epiphytoty ye-Fusarium wilt kumazambane kwahlotshaniswa nezimo zika-2011: ngemuva kwezimvula ezinamandla zikaJuni, ngenxa yalokho inhlabathi yalahlekelwa ngokuphelele isakhiwo sayo, bese, ngemva kwesikhathi eside sesomiso, ngokumelene nesizinda se amazinga okushisa aphezulu, ukucinana kwenhlabathi eqinile kakhulu kanye nokuncipha kwenzeka ngokwakhiwa kwemifantu. Isikhunta saqala ukungena esimisweni sezimpande zezitshalo ezibuthakathaka; lokhu kwabuye kwenziwa lula ukuqhekeka nokulimala kwezimpande. Ukuthuthukiswa kwesikhunta ohlelweni lwe-vascular of the underground and above-ground parts of the plant kwaholela ekuvinjweni okuphelele kwesistimu yokuqhuba kanye nokubuna kwezitshalo ekuqaleni kukaJulayi-August, ngokwakhiwa okukhulayo kwezilimo eziyizigaxa ezinokubola kwe-stolon (Fig. . 1, ezihlukahlukene Nevsky). Imvula enkulu ngoJuni kanye nesomiso esalandela kanye namazinga okushisa aphezulu kwamboza ingxenye enkulu ye-republic, ngakho-ke i-Fusarium wilt ngo-2011 nayo yaba nomthelela kukho konke ukutshalwa kwamazambane - kokubili ekukhiqizeni okuncane nokukhulu. Imvula ena ngoSepthemba yathambisa inhlabathi, kodwa ngalesi sikhathi izitshalo zase zithinteke ngokuphelele yilesi sifo futhi zibunile.
irayisi 1. I-tuber ehlukahlukene ye-Nevsky ene-stolon rot ngo-2011
Imbewu esetshenziswe ukutshala ngo-2011, etholwe endaweni ngonyaka odlule, ayizange itheleleke nge-vascular fusarium, kusukela ngonyaka ongathandeki ka-2010, i-tuberization yenzeke ngo-September-Okthoba emazingeni aphansi okushisa kanye nezimo ezinomswakama.
Ngo-2011, ukomiswa kwenhlabathi eshumini lesibili noma lesithathu likaJulayi kwaqondana nesikhathi se-tuberization ezinhlobonhlobo zasekuqaleni ze-Nevsky, ngakho-ke lezi zinhlobonhlobo zabonisa izimpawu ezinzima zokukhula kokubola kwe-stolon ezigabeni.
Ngaphansi kwezimo zika-2012, sabona izikhathi ezimbili ezomile, ezazihambisana nokomisa emhlabathini futhi zaziyingozi ekulimazeni i-Fusarium wilt - kusukela ezinsukwini eziyishumi zesithathu zikaJuni kuya ezinsukwini eziyishumi zokuqala zikaJulayi (izinsuku ezingu-20), futhi kusukela ezinsukwini zokuqala kuya kweziyishumi zika-August (izinsuku ezingu-20).
Imbewu esetshenziswe ukutshala ngo-2012 yathinteka kamuva yi-vascular fusarium. Kwamanye amapulazi, kakade ngesikhathi sokugcina, imbewu yezinhlobonhlobo zamazambane ezivuthwa zakuqala i-Vitessa, eyayivela ezindaweni eziseningizimu yeRussian Federation, yabola ngokuphelele. Ekupheleni kukaMeyi - ekuqaleni kukaJuni, ngemuva kokulungiswa okuphindaphindiwe, imbewu yezinhlobonhlobo zamazambane aphakathi nendawo i-Nevsky, ekhule epulazini lesifunda saseTukaevsky eRiphabhulikhi yaseTatarstan, yabola ngokuphelele. Ezinye izinhlobo zamazambane azizange zibonise umonakalo osobala we-vascular fusarium lapho zihlungwa, kodwa ngemva kokutshala zabonisa ukukhula okuqinile nokubuthakathaka (izinhlobonhlobo ze-Zekura ezimaphakathi nesizini epulazini esifundeni sase-Elabuga).
Ngo-2012, amazinga enhlabathi e-Fusarium wilt infection ayephezulu kakhulu emapulazini aphinde atshala amazambane ezindaweni ezifanayo eziniselwa lapho amazambane atshalwa khona ngo-2011. Kwakukule mikhakha lapho kwabonwa khona isithombe esicindezela kakhulu - ukuhluma kwakungekho ngaphezu kwama-50%, futhi izitshalo ezisakhulayo zahluleka ukukhula. Cishe kwakungekho sivuno noma yayingenwe, phakathi kwezinye izinto, ngokubola kwe-stolon futhi yayibole kakhulu ngesikhathi igcinwa.
Ngakho-ke, inhlanganisela yokungcoliswa kwenhlabathi ngenxa yokuntuleka kokushintshaniswa kwezitshalo kanye nokungcoliswa okufihliwe kwezinto zembewu kwaholela emiphumeleni emibi kakhulu.
a) b)
Fig.2. Izimpawu ze-fusarium wilt ohlelweni lokuqhuba (a), ohlelweni lwe-vascular of tuber (b)
Isimo samazambane sasingcono kakhulu emapulazini ayetshala amazambane ngaphansi kokuniselwa nangokushintshaniswa kwezitshalo.Isibonelo, izinhlobonhlobo ze-Arosa zinikeze isivuno esingu-30-35 t/ha emapulazini asesifundeni sase-Arsky naseTukaevsky; ngaphezu kwalokho, la mazambane agcinwa. kahle, naphezu kokuthi ensimini ngo-September kwakukhona ukusabalala okukhulu kwezimpawu ze-Fusarium wilt emaqabunga apical ezitshalo kanye ne-browning yezimpande (Fig. 3).
Kumele kuqashelwe ukuthi imbewu yamazambane yezinhlobo ze-Arosa, Felox, Zekura, ezilethwe ngokuqondile eJalimane, ezingathinteki i-vascular fusarium, lapho zikhule ngaphansi kwezimo eziniselwayo, ngokuhambisana nokushintshaniswa kwezitshalo, nokho, zembula ukusabalala okukhulu kwezimpawu ze-fusarium wilt. , kuhlanganise nezimpande Okungukuthi, izimo ezivumayo - izinga lokushisa eliphezulu, umswakama kanye nokomisa emhlabathini - kwakubaluleke kakhulu, lesi sifo saqala ukukhula ngisho nalapho kungekho ukutheleleka okunamandla kwembewu kanye nenhlabathi.
Ngo-2012, isikhathi sokuma kwenhlabathi ngezinsuku eziyishumi zesithathu zikaJuni kanye nezinsuku eziyishumi zokuqala zikaJulayi saqondana nesikhathi sokuvuthwa kwezinhlobo zokuqala zokuvuthwa, ngakho-ke, amapulazi ezolimo abona ukwanda kokutheleleka kwezilimo eziyizigaxa nge-vascular fusarium ekuvuneni. zalezi zinhlobonhlobo, ikakhulukazi izinhlobonhlobo ze-Udacha (Fig. 2 b).
Ukusabalala kwe-vascular fusarium ngendlela efihlekile nakho kwakuphakeme kakhulu ezinhlotsheni zakuqala iZhukovsky ranniy ne-Rozara, ephansi phakathi nezinhlobo zakudala ze-Nevsky ne-Radonezhsky, futhi zehla ngisho naphakathi nesizini ehlukahlukene i-Ladozhsky.
Ekukhiqizeni okuncane ngo-2012, imbewu yokuzala kancane, esanda kuthinteka yi-Fusarium, kanye nenhlabathi engcolile yaholela ekuvuneni okuncane, ngisho nasemhlabeni ocebile kakhulu wezinto eziphilayo. Ngokusobala, emhlabathini ocindezelayo, ukululama ekuthelelekeni okwaqoqwa ngo-2011 kwakuhamba kancane kunesidingo ngenxa yokuntuleka kwesikhathi sokunciphisa umsebenzi wesikhunta.
Fig.3. Ukuthuthukiswa okukhulu kwe-fusarium wilt ensimini yamazambane (epiphytoty)
Ngaphansi kwezimo zika-2013, imvula yayingalingani kakhulu kunango-2012. Ukuvela kwezithombo nokukhula okuqhubekayo kwamazambane ngenxa yokushisa okuphezulu kanye nesomiso ngoMeyi-Juni kwenzeka ngokubambezeleka okungaba amasonto amabili; ngesikhathi sokukhula, izitshalo zaba buthaka ngenxa yokuntuleka komswakama emhlabathini kanye namazinga okushisa aphezulu emini. Kusukela ezinsukwini eziyishumi zesibili zikaJulayi kuya ezinsukwini eziyishumi zokuqala zika-Okthoba, izikhathi ezinhlanu ezinezinsuku eziyishumi ziphindaphinda ngokulandelana - enye ibe nemvula enkulu futhi enye ngaphandle kwemvula. Izikhathi ezintathu zokuqala zenzeka emazingeni okushisa aphezulu emini futhi zaba nomthelela ekusabalaleni okusebenzayo kwe-Fusarium wilt. Izinkathi ezimbili ezilandelayo zokuna kwemvula enamandla kanye namazinga okushisa aphansi kwabangela ukubola kwemithambo ye-fusarium yezilimo eziyizigaxa ukuba ziguquke zibe ukubola okumanzi emhlabathini ngaphambi kokuba kuqale ukuvunwa.
Izinto zokutshala amazambane ngo-2013 zathinteka kamuva yi-vascular fusarium, kodwa ngamazinga ahlukahlukene, kuye ngezinhlobonhlobo nezimo zokutshalwa kwawo epulazini ngonyaka odlule.
Entwasahlobo ka-2013, sathola esinye isici sokuthuthukiswa kwe-fusarium ye-vascular efihlekile ekutshaleni izilimo eziyizigaxa zamazambane. Ngaphansi kwezimo zokukhiqiza, izinto ezifanayo zahluma entwasahlobo emazingeni okushisa ahlukene futhi kwatholakala imiphumela ehlukene. Amazambane ahluma ezingeni lokushisa elingu-15° C anikeza isivuno esingu-20-25 t/ha, kanti nezigaxa ezihluma emazingeni aphezulu okushisa emini angu-25-30° C abola ngaphambi kokutshala. Lokhu kubuka kwenze kwaba nokwenzeka ukuchaza icala lika-2006: sabe sesithumela ingxenye yamazambane embewu e-Astrakhan ukuze itshalwe ehlobo, kodwa indaba ayizange isetshenziswe ngokuphelele ezinsukwini ezimbalwa nje. Ngesikhathi esifanayo, amazambane eqoqweni elifanayo emasimini e-republic yethu anikeza isivuno esihle.
Ngokusobala, emazingeni okushisa aphezulu, okuye kwabonwa e-republic eminyakeni yamuva nje phakathi nokuhluma kwentwasahlobo, sakha izimo ezivumela ukuthuthukiswa kwe-vascular fusarium kuma-tubers njengase-Astrakhan ngesikhathi sokutshala ehlobo.
Ngakho-ke, amazinga okushisa aphezulu (ngaphezu kuka-20-25 C) ngesikhathi sokuhluma kwentwasahlobo akhuthaza ukukhula kwesikhunta kuma-tubers asanda kuthinteka yi-vascular fusarium.
Ngaphansi kwezimo zokomiswa okuphindaphindiwe kwenhlabathi ngo-2013, zonke izinhlobo zamazambane, ngezinga elilodwa noma elinye, zathinteka yi-Fusarium wilt ensimini, nezilimo eziyizigaxa zathinteka yi-vascular fusarium (Fig. 4).
Ngenxa yokwanda komswakama womoya kanye namazinga okushisa aphansi ngesikhathi sokuvuna, amazambane angena endaweni yokugcina ayengasomile kahle, ngakho-ke kakade ekwindla, ukubola okukhulayo kwezilimo eziyizigaxa kwabonwa ezindaweni zokugcina impahla, imbangela yayo kwakuyi-vascular fusarium, eyathinta ukubola. nezilimo eziyizigaxa ensimini. Ukudlondlobala kwe-vascular fusarium ngendlela efihlekile kumazambane embewu yezinye izinhlobo ezitshalwe endaweni okulinganiselwa ku-2014-15% ngoFebhuwari 20.
a) b)
Ilayisi. Izimpawu ezi-4 ze-fusarium wilt ezitshalweni zamazambane ngo-2013:
a) umbala we-anthocyanin kanye nokugoqa amaqabunga e-apical emkhunjini,
b) ukubola okomile (ukubola) kwengxenye engaphansi kwesiqu.
Isifingqo
Ngemuva kokutheleleka kwe-epiphytotic yamazambane yi-Fusarium wilt ngo-2011, ukusabalala kwalesi sifo e-republic bekulokhu kuqhubeka ngempumelelo enkulu noma encane iminyaka emithathu. Kumele kukhunjulwe ukuthi kulokhu izinqubo ezimbili ze-multidirectional ziyaqhubeka kanyekanye. Okokuqala ukubuyiswa kwenhlabathi namazambane ezifweni. Inqubo yesibili ukutheleleka okusha okubangelwa izimo eziphindaphindayo zaminyaka yonke ezivuna ukuthuthukiswa kwesikhunta.
Ngokubona kwethu, ngemuva kokutheleleka nge-100% nge-fusarium wilt yamazambane ngo-2011, kukhona ukululama kancane kancane kwenhlabathi nembewu kusuka ku-vascular fusarium.
Njengoba ulwazi lwango-2012 lwabonisa, ingozi enkulu inhlabathi lapho ukukhula nokufa kwezitshalo ezithinteke ngenxa ye-Fusarium wilt kwenzeka khona. Ngakho-ke, amazambane kufanele atshalwe ngokushintshaniswa kwezitshalo. Emhlabathini ocindezelayo, imithombo ye-Fusarium wilt iyacindezelwa, kepha ngemuva kwama-epiphytoties aqinile, njengango-2011, umsebenzi we-microflora yenhlabathi ungase unganele ukucindezela i-Fusarium ngonyaka olandelayo; izinyathelo ezengeziwe ziyadingeka.
Isikhunta sohlobo lwe-Fusarium yizilokazane ezisebenzayo noma ama-saprophyte. Babola ngenkuthalo imfucumfucu yezitshalo ezifile ewela emhlabathini, futhi ngaleyo ndlela yenze umsebenzi owusizo. Kodwa uma izimo ezicindezelayo zenzeka, izitshalo ezibuthakathaka (eziphila ingxenye) zingathinteka.
Ezindaweni zomuntu siqu, ukusetshenziswa kwekwindla komanyolo we-organic kungasiza ukuqinisa umsebenzi we-saprophytic we-fungus ekuboleni izinsalela zezinto eziphilayo, futhi ukusetshenziswa kwentwasahlobo, ikakhulukazi entwasahlobo eyomile, kunokuba, ngokuphambene nalokho, kube nomthelela ekomisweni kwenhlabathi. kanye nokwanda komsebenzi we-parasitic we-fungus.
Ukunisela okuhle, okuvamile kungaholela emhlabathini onempilo kanye nezitshalo. Ukunisela ngendlela engafanele, okwenza umhlabathi wome ngemva kokuchelela kanzima, kungandisa isifo se-Fusarium wilt. Ngomswakama ophezulu wenhlabathi, i-Fusarium ikhula kahle, futhi ngemva kokoma, ihlasela izitshalo ezibuthakathaka, njengoba iningi labaphikisi be-fungal ngokusobala lifa ezimeni ezomile.
Imbewu yembewu ehlaselwe yi-vascular fusarium ingaveza isivuno esingathinteki, okungukuthi, ukudluliswa kwe-fusarium enzalweni akuwona amaphesenti ayikhulu futhi kuncike ezimweni zangaphandle ezikhona. Ukunikeza izitshalo ensimini ngomanyolo kanye nomswakama kuzivumela ukuthi zimelane nezifo.
Izinga lembewu libaluleke kakhulu: ukuzala okuphezulu, ngaphandle kwezifo ezibangelwa amagciwane, kukhule ngenkuthalo futhi amelana kakhulu nokulimala kwe-Fusarium wilt.
Kuyadingeka ukulawula ukuthuthukiswa kwe-fusarium lapho ugcina izilimo eziyizigaxa. Amazinga okushisa aphakeme kakhulu lapho kuhluma izilimo eziyizigaxa entwasahlobo kungaholela ekwandeni kokuthuthukiswa kwesikhunta, okungaholela ekuboleni okuphelele kwamazambane.
Kungenzeka ukubikezela ukuthuthukiswa kwe-vascular fusarium ngokuya ngezinhlobonhlobo zamazambane - uma isikhathi sokuqhakaza kwe-tuberization senzeka ezimweni zokushisa okuphezulu kanye nokomisa emhlabathini omanzi, khona-ke ukutheleleka okufihliwe nge-vascular fusarium kuzosakazeka kakhulu.
Lapho ugcina izilimo eziyizigaxa ngomonakalo ofihliwe yi-vascular fusarium, izigaba zokuqala zibaluleke kakhulu - ukomisa, isikhathi sokuphulukisa, ukupholisa. Kuyadingeka ukomisa umswakama ongaphezulu kuma-tubers ngokushesha ngangokunokwenzeka, ngoba ngosizo lwayo ukutheleleka kwanda, bese kuvela amaphakethe okubola okumanzi. Uma izilimo eziyizigaxa zifika endaweni yokugcina zimanzi (njengango-2013), kuyadingeka ukomisa ubusuku nemini kuze kube yilapho umswakama ususwa ngokuphelele ebusweni bezilimo eziyizigaxa.
Ukuze ushintshe kakhulu isimo ngokubola kwezimpande futhi ulwe nokulimala kwe-Fusarium wilt lapho inhlabathi yomile, kuyadingeka ukwandisa ukuvunda kwenhlabathi, ukwethula izitshalo zomquba oluhlaza ekujikelezweni kwezitshalo, futhi kwakhiwe ungqimba lwe-mulch olunciphisa ukushintshwa komswakama emhlabathini.
Imbewu etshalwe ezindaweni eziseningizimu ingaba nesifo esicashile esiphezulu se-vascular fusarium ngenxa yamazinga okushisa aphezulu atholakala kulezi zindawo.
Isibikezelo sika-2014
In 2014 Ngonyaka Izinto zokutshala amazambane ngeke zithinteke kancane yi-vascular fusarium ngenxa yokubonakaliswa okubonakalayo kwalesi sifo kanye nokuqothulwa kwezilimo eziyizigaxa ezithintekile kakade ekwindla ngesikhathi sokuvuna. Ukukhula okuqhubekayo kwalesi sifo ezitshalweni ensimini kuzoncika esimweni sokuhluma kanye nesimo sezulu ngesikhathi sokukhula. Ukuze izitshalo zikwazi ukumelana nezifo, kubalulekile ukuzidalela izimo ezifanele.
Izincomo ezengeziwe zokuvikela amazambane ku-Fusarium wilt:
- sebenzisa ukukhiqiza okuphezulu kokutshala (i-super elite, elite, ukukhiqiza kokuqala), okunamandla okukhula okuphezulu futhi okukwazi ukumelana nezifo;
- khulisa izinhlobo ezinezikhathi ezihlukene zokuvuthwa ukuze kuncishiswe ubungozi benkathi yokukhula kwe-tuberization ehambisana nezikhathi ezivumayo zokukhula kwe-Fusarium wilt;
- izilimo eziyizigaxa kufanele zihlume ngemuva kokuhlungwa ekushiseni okungaphezu kuka-8-15 ° C, ukugwema ukwakheka kwamahlumela amade;
- ungajuli - ukujula okuphezulu kokutshala akufanele kudlule ububanzi bezilimo eziyizigaxa - 5-6 cm;
– qaphela izinga lokushisa lapho utshala - izinga lokushisa elifanele lomhlabathi ekujuleni kokutshala lingu-8° C (izinsuku eziyishumi zesibili zikaMeyi). Uma kunenhlabathi emanzi kanye nokufudumala komoya okungazelelwe ku-25-30 ° C, sincoma ukubambezeleka ukutshala usuku olulodwa noma ezimbili ukuze kugxilwe umsebenzi wesikhunta emsebenzini we-saprotrophic wokucubungula izinsalela eziphilayo emhlabathini;
- tshala amazambane emapulazini amakhulu ngokushintshanisa izitshalo zensimu engu-4-5, nasezindaweni zomuntu siqu - ngokushintshanisa izitshalo nokusebenzisa umanyolo wemvelo;
- qapha isimo songqimba lwenhlabathi engaphezulu - inhlabathi kufanele ikhululeke ekujuleni okungama-20 cm;
- yenza ukwelashwa kwangaphambi kokutshala kwezilimo eziyizigaxa (kwandisa ukuhluma futhi kusheshise ukukhula kwezitshalo, ngakho-ke, kuvikela ezifweni):
- amalungiselelo microbiological - "Fitosporin MF", "Flavobacterin" + "Agrofil", "Extrasol";
- izidakamizwa eziphilayo ezisebenzayo - "Zircon", "Siliplant", "Epin-Extra", "Melafen", "Albit", "humates", njll.;
- sebenzisa umanyolo oyisisekelo ngenani elibaliwe lesivuno esihleliwe, kuye ngokuba khona kokunisela, ukutholakala komhlabathi, kanye nendlela yokufaka isicelo;
- ngesikhathi sokuhluma kanye ne-tuberization ezimweni zokukhiqiza, yenza ukudla okuphindwe kabili kwe-foliar nge-"Aquarin" (Babonisa ukusebenza kahle okuphezulu, futhi, okubaluleke kakhulu lapho izimo zesomiso ezicindezelayo ziqala, umphumela wabonakala emahoreni ambalwa, "I-Aquarin" ingabizwa ngokuthi "i-ambulensi" ); ngaphansi kwezimo zomswakama ojwayelekile kanye nokunisela, ukusebenza kahle kwazo zonke ezinye izidakamizwa ze-biologically kuphezulu;
- ungavumeli inhlabathi yome lapho unisela amazambane;
-sika iziqongo ezinsukwini eziyi-7-10 ngaphambi kokuvuna ukuze ukhokhobe izikhumba ze-tuber;
- qaphela ngokukhethekile izilimo eziyizigaxa lapho uzigcina ngeminyaka enezimo ezimanzi;
- gwema ukujuluka nokugcwala kwamanzi kwezilimo eziyizigaxa ngesikhathi sokugcina.