Lo mbhalo uvela kufayela le- Ukukhishwa kukaDisemba 2021 Umtshali Wamazambane.
Izifo zamazambane ezifana nechashazi elimnyama (Amakhodi we-Colletotrichum) kanye ne-silver scurf (I-Helminthosporium solani) kubangela amabala esikhumba, okungaholela ekwehleni kwenani lemakethe lesilimo. Ukutheleleka nge C. amakhodi futhi H. solani akuthinti nje kuphela izinga kanye nesivuno samazambane, kodwa futhi asebenze njengomthombo obalulekile we-inoculum yezitshalo zesikhathi esizayo ngokuhlwanyela izilimo eziyizigaxa zembewu.
Izifo ezifana nechashazi elimnyama kanye ne-silver scurf ngokuvamile azibonakali ngesikhathi sokuvuna noma ukugcinwa kusenesikhathi; ngokuvamile zivela ngemva kwenyanga eyodwa kuya kwezintathu ngemva kokuba izilimo eziyizigaxa zibekwe endaweni yokugcina. Kubaluleke kakhulu ukunquma ukuthi yisiphi isifo esinamabala onaso, njengoba izindlela zokuphatha zokulawula lezi zifo zihluke kakhulu.
Ichashazi elimnyama yisifo esivamile samazambane esivame ukubonwa kuma-tubers, kodwa singathinta zonke izingxenye zesitshalo. Iqanjwe nge-microsclerotia eyakha ezigabeni futhi ngokuvamile ibonakala nje ngeso lenyama. Izimpawu ze-Tuber zivela njengezisihla ezinsundu kuye kwezimpunga engxenyeni enkulu ye-tuber, noma njengeziyingi ukuya ezindaweni ezinokwakheka okungavamile. Ichashazi elimnyama lingase lithuthuke njenge-silvery sheen ngesikhathi sokugcinwa, okungase kudidaniswe ne-silver scurf. Kodwa-ke, ichashazi elimnyama livamise ukukhombisa amapeshi anomumo ongajwayelekile anamamajini angacaciswe kahle kakhulu kune-scurf esiliva. Ukuhlola ngelensi yesandla (10×) kuzohlukanisa ngokushesha amachashazi amnyama anezikhala emicu enqwabelene ye-scurf esiliva.
I-ilver scurf ivela kuphela kuma-tubers. Nakuba amanye ama-tubers etheleleka ensimini, umonakalo omkhulu uvame ukwenzeka ngemva kokuba izilimo eziyizigaxa sezigcinwe isikhathi esingangenyanga noma ngaphezulu. Izilonda ezidalwe endaweni yokugcina ziyindilinga futhi zinamaphethelo aqondile. Kodwa-ke, njengoba lesi sifo siqhubeka endaweni yokugcina, izilonda zomuntu ngamunye zingahlangana, ekugcineni zimboze yonke indawo ye-tuber. Ukubukeka kwezilonda ezisiliva kubonakala kakhulu lapho izigaxa zimanzi futhi ziphuma emaphaketheni omoya kumaseli afile e-periderm (isikhumba). Ngemva kwezinyanga ezimbalwa igcinwe, i-epidermis ngaphansi kwezilonda ze-scurf esiliva iyaqhekeka, futhi izilimo eziyizigaxa ziyashwabana futhi zishwabane ngenxa yokulahlekelwa amanzi kakhulu. Kodwa-ke, izilonda ze-scurf ezisiliva zihlala zikha phezulu, azibangeli monakalo ezicutshini ezingaphansi.
Ukwenza izinto zibe nzima nakakhulu, zombili izifo zingaba khona ku-tuber efanayo. Ngechashazi elimnyama, konke ukutheleleka kwezilimo eziyizigaxa kwenzeka ensimini ngaphambi kokuba i-tuber periderm ivuthwe. Uma i-periderm seyakhekile futhi nezilimo eziyizigaxa “sezibekiwe isikhumba,” ukutheleleka ngechashaza elimnyama ngeke kusenzeka. Kodwa-ke, nge-silver scurf, ama-tubers angenwa kalula ukutheleleka ngemva kokuba i-periderm isiqalile ukuvuthwa. Ngakho-ke, uma kukhulunywa nge-silver scurf, isikhathi sezilimo eziyizigaxa esisichitha ensimini ngemuva kokumiswa kwesikhumba kanye nesikhathi esigciniwe siyanqwabelana ukuze kuthuthukiswe izifo. Izilimo eziyizigaxa ezingenwe ichashazi elimnyama ensimini zingase zitheleleke nge-silver scurf endaweni yokugcina.
Zombili lezi zifo zilawulwa ngokuyinhloko kusetshenziswa imikhuba yamasiko kanye nama-fungicides. Ucwaningo luye lwahlobanisa izehlakalo eziphezulu kanye nokuqina kwechashazi elimnyama endaweni yokugcina namazinga aphezulu e-black inoculum emhlabathini ngesikhathi sokutshala. Le miphumela ihlobana kahle nocwaningo lwaseNyuvesi yase-Idaho olwabonisa ukuncipha kwamazinga amachashazi amnyama endaweni yokugcina lapho izilimo eziyizigaxa zivikelekile emiseleni lapho zitshalwa ngama-fungicides.
Imbewu enegciwane iwumthombo oyinhloko we-silver scurf inoculum, futhi ukwelashwa kwembewu kuphumelela ekwehliseni i-silver scurf kodwa ngeke kuvimbele konke ukutheleleka kwezilimo eziyizigaxa zamantombazane. Kodwa-ke, ngokungafani nechashazi elimnyama, kunezibulala-fungi eziningana zangemva kokuvuna, ngaphambi kokugcinwa ezingalawula i-scurf esiliva endaweni yokugcina. Ucwaningo luye lwabonisa ukuthi ukusetshenziswa kwemikhiqizo ye-phosphorus acid (isb., Resist 57, Phostrol) kanye ne-fungicide Stadium ukuze kuphumelele ekulawuleni i-scurf esiliva endaweni yokugcina, ikakhulukazi uma amazinga okutheleleka ephansi ukuya kokulinganisela.
Ngokungafani ne-silver scurf, ichashazi elimnyama alisakazeki endaweni yokugcina. Kodwa-ke, ukuqina kwesifo kuzokwanda ezigabeni ezinegciwane endaweni yokugcina uma izimo zivuma. Izilimo eziyizigaxa ezinamachashazi amnyama ezingena endaweni yokubeka zingase zibukeke zingenazo izifo ngokuphelele. Kodwa-ke, ngaphansi kwezimo ezivumayo, i-fungal mycelia izokhula ku-microsclerotia futhi iqoqe indawo yamazambane, ibangele izilonda ezikhulayo ngemva kwezinyanga ezimbili kuya kwezintathu zokugcinwa. Lokhu kungaholela kumbono wokuthi ukutheleleka nesifo kwenzeka endaweni yokugcina. Ukuphatha izinga lokushisa nomswakama endaweni yokugcina kungabambezela noma kuvimbele ukuqala kokukhula kwamachashazi amnyama.
Ukutheleleka okukhulu kwe-silver scurf kungenzeka endaweni yokugcina, ngezinye izikhathi kuthinte zonke izilimo eziyizigaxa endaweni yokugcina. Ukuthi singakanani isifo esikhula kuncike enanini lezilimo eziyizigaxa ezinegciwane ezizogcinwa, izimo zemvelo lapho zigcinwa khona, nokuthi zigcinwa isikhathi esingakanani izilimo eziyizigaxa. Njengasechashazi elimnyama, amazinga okushisa apholile, umswakama ophansi kanye nokukhipha umoya okwanele kusiza ukunciphisa ukukhula kwe-scurf esiliva endaweni yokugcina. Ukushintsha indawo yokugcina izinto ngeke kuqede ukuthuthukiswa kwe-silver scurf, kodwa kuzonciphisa ukukhiqizwa kwezinhlamvu kanye nokutheleleka kwesibili kwezilimo eziyizigaxa ezinempilo.
Uma kuhlelwa ukugcinwa kwesikhathi eside, indawo yokugcina akufanele ivulwe ukuze kupakishwe futhi kuthunyelwe ingxenye yendawo bese ivalwa kabusha. Ukulahlekelwa okukhulu kuye kwenzeka ezimweni ezinjalo, ngenxa yokuxoshwa kwezinhlamvu ngokusetshenziswa kwemishini kanye nokwehluka kwengcindezi lapho kuvulwa isitoreji, uhlelo lomoya bese lusakaza ama-pathogen spores kuyo yonke inqwaba.
Kafushane, uma uqala ukuqaphela amazinga akhulayo ezifo ezingcolile kumazambane akho agciniwe, kubalulekile ukunquma ukuthi une-silver scurf noma ukutheleleka kwamachashazi amnyama. I-Silver scurf ingaholela kwesinye isifo ngenxa yokutheleleka kwesibili endaweni yokugcina. Ichashazi elimnyama ngeke liholele ekuthelelekeni okwengeziwe kwezilimo eziyizigaxa ezinempilo, kodwa izimpawu ezengeziwe zingase zivele ezigabeni esezithelelekile kakade. Kunoma yikuphi, kungcono kakhulu ukupakisha futhi uthumele izigaxa emakethe entsha ngokushesha okukhulu. Uma kuhlelwe ukugcinwa isikhathi eside, ungayivuli indawo yokugcina, futhi ugcine amazinga okushisa esezingeni eliphansi lokusebenzisa amazambane ukuvimbela ukukhula kwezifo.