Izitshalo zizivikela kanjani kuma-microorganisms we-pathogenic? Lena iphazili eyinkimbinkimbi, lapho ithimba lezazi zebhayoloji laseNyuvesi yase-Amsterdam lixazulule ucezu olusha. Ithimba, eliholwa ngu-Harrold van den Burg, lithole ukuthi nakuba izimbotshana zamanzi (ama-hydathodes) emaqabunga zinikeza indawo yokungena kumagciwane, nazo ziyingxenye esebenzayo yokuzivikela kulaba bahlaseli. Ucwaningo lwethimba manje selushicilelwe kujenali Biology yamanje.
Noma ubani ojwayele ukunikeza izitshalo amanzi amaningi angase ayazi le nto: amaconsi amancane obisi lwezitshalo ngezinye izikhathi avela emaphethelweni amaqabunga, ikakhulukazi ebusuku. Lapho izitshalo zithatha amanzi amaningi ngezimpande zazo kunokuba zilahleka ngenxa yokuhwamuka, zingasebenzisa izimbotshana zazo zamanzi emaphethelweni eqabunga ukuze zikhiphe amanzi amaningi. Izimbotshana zivimbela ngokoqobo umfutho wamanzi ezimpande ekubeni uphakame kakhulu. Lena indlela ebalulekile, kodwa ngesikhathi esifanayo, eyingozi. Ama-microorganisms we-Pathogenic angangena emithanjeni yesitshalo ngalawa maconsi omuncu ukuze aqoqe izimbotshana zamanzi.
Ngakho-ke izazi zezinto eziphilayo bezilokhu zizibuza isikhathi eside: Izitshalo zizivikela kanjani kule ndawo yokungena evulekile? Ingabe lezo zimbotshana zamanzi, ama-hydathodes, izindlala ezingenakuzivikela ezivumela ukungena okwanele kwezinambuzane eziyingozi? Noma ingabe ziye zavela ngendlela yokuthi zibe yingxenye yokuzivikela kwesitshalo emagciwaneni?
Umugqa wokuzivikela
Ithimba labacwaningi abavela eSwammerdam Institute for Life Sciences eNyuvesi yase-Amsterdam lithole ubufakazi bokuthi lokhu kwakamuva kunjalo. Kujenali Biology yamanje, bachaza ukuhlola kwabo ngesitshalo esiyimodeli i-Arabidopsis nezinhlobo ezimbili eziyingozi amabhaktheriya. I-Arabidopsis, noma i-thale cress, ihlobene nazo zonke izinhlobo zeklabishi nezinye ezidliwayo izitshalo emndenini weBrassicaceae. Izazi zesayensi yezinto eziphilayo zathola ukuthi izimbotshana zamanzi ziyingxenye yomugqa wokuqala nowesibili wesitshalo wokuzivikela emagciwaneni. Ngamanye amazwi, bahileleke kukho kokubili ukusabela kokuqala okusheshayo kanye nezenzo zokulandelela ngokumelene nabahlaseli.
U-Harrold van den Burg, owahola ithimba labacwaningi, uyachaza, “Kulolu cwaningo, sasebenzisa i-Arabidopsis mutants enokushoda emazingeni azo. izivikeli mzimba lokho kwabenza bakwazi ukungenwa kalula yigciwane i-Xanthomonas campestris kanye ne-Pseudomonas syringae. Sikhethe la magciwane ngoba adala izinkinga ezimbi kwezolimo. Lapha zazisetshenziselwa ukukhulula amasosha omzimba ezitshalo.
“Sikwazile ukuthola ukuthi ama-protein complexes amabili (kulabo abanentshisekelo: BAK1 kanye ne-EDS1-PAD4-ADR1) avimbela amabhaktheriya ukuthi angaphindaphindi ezimbotsheni zamanzi. Izimpendulo ezifanayo zokuzivikela komzimba ziphinde zivimbele lawa magciwane ukuthi aqhubekele phambili angene ngaphakathi kwesitshalo. Ngaphezu kwalokho, sathola ukuthi lapho lo mzila wokuqala wokuzivikela uvela, izimbotshana zamanzi zikhiqiza uphawu olubangela ukuthi lesi sitshalo sikhiqize ama-hormone acindezela ukusakazeka okwengeziwe kwamagciwane ahlaselayo esimisweni semithambo.”
Yenza izilimo zezolimo zikwazi ukumelana nezimo
Ngakho-ke leli thimba linikeza ukuqonda okubalulekile okubalulekile kokuthi lezi zindawo zokungena zemvelo zamagciwane ziye zavela kanjani futhi zivikelwe amasosha omzimba esitshalo. Ngokuhamba kwesikhathi, lokhu kungasiza ekwenzeni izitshalo zezolimo zimelane nezifo ezibangelwa amagciwane.
UVan den Burg uyaphawula, “Okwamanje sizoqhubeka nalolu cwaningo. Isibonelo, manje sesiyazi ukuthi yimaphi ama-protein complexes ahilelekile ekuvimbeleni amagciwane ukuthi aphindaphindeke ezimbotsheni zamanzi, kodwa hhayi ukuthi lokhu kwenzeka kanjani. Ingabe ngokwesibonelo alawula ukukhiqizwa kwezinto ezilwa namagciwane kuma-hydathodes avimbela ukukhula kwamagciwane? Lokho kungajabulisa ukwazi. Uma sikuqonda kangcono lokhu, kulapho sisondelana kakhulu nohlelo lokusebenza olusebenzayo lokuvikela okungcono izitshalo zezolimo. "