Fasahar injiniyan noma ta lambun kore An buga a Beijing da ƙarfe 17:30 a ranar 13 ga Janairu, 2023.

Shakar yawancin abubuwan gina jiki tsari ne da ke da alaƙa da ayyukan metabolism na tushen tsirrai. Waɗannan hanyoyin suna buƙatar kuzarin da numfashin ƙwayoyin halitta ke samarwa, kuma shaƙar ruwa kuma ana daidaita shi ta hanyar zafin jiki da numfashi, kuma numfashi yana buƙatar haɗin oxygen, don haka iskar oxygen a cikin yanayin tushen yana da tasiri mai mahimmanci akan ci gaban amfanin gona na yau da kullun. Yawan iskar oxygen da ke narkewa a cikin ruwa yana shafar zafin jiki da gishiri, kuma tsarin substrate yana ƙayyade yawan iska a cikin yanayin tushen. Ban ruwa yana da manyan bambance-bambance a cikin sabuntawa da ƙara yawan iskar oxygen a cikin substrates tare da yanayin ruwa daban-daban. Akwai dalilai da yawa don inganta yawan iskar oxygen a cikin yanayin tushen, amma matakin tasirin kowane abu ya bambanta sosai. Kula da ƙarfin riƙe ruwa mai ma'ana (abin da ke cikin iska) shine jigon kiyaye yawan iskar oxygen a cikin yanayin tushen.

Tasirin zafin jiki da gishiri akan cikakken iskar oxygen a cikin maganin

Iskar oxygen da ta narke a cikin ruwa

Iskar oxygen da ta narke tana narkewa a cikin iskar oxygen mara ɗaurewa ko kuma kyauta a cikin ruwa, kuma yawan iskar oxygen da ta narke a cikin ruwa zai kai matsakaicinsa a wani zafin jiki, wanda shine cikakken adadin iskar oxygen. Yawan iskar oxygen da ke cikin ruwa yana canzawa tare da zafin jiki, kuma lokacin da zafin jiki ya ƙaru, yawan iskar oxygen yana raguwa. Yawan iskar oxygen da ke cikin ruwa mai tsabta ya fi na ruwan teku mai ɗauke da gishiri girma (Hoto na 1), don haka yawan iskar oxygen da ke cikin ruwan sinadaran da ke ɗauke da sinadarai daban-daban zai bambanta.

Jigilar iskar oxygen a cikin matrix

Iskar oxygen da tushen amfanin gona na greenhouse zai iya samu daga ruwan sinadaran gina jiki dole ne ya kasance cikin yanayi na 'yanci, kuma ana jigilar iskar oxygen a cikin substrate ta hanyar iska da ruwa da ruwa a kusa da tushen. Idan yana cikin daidaito da iskar oxygen a cikin iska a wani zafin jiki da aka ƙayyade, iskar oxygen da ke narkewa a cikin ruwa ya kai matsakaicin, kuma canjin iskar oxygen a cikin iska zai haifar da canjin iskar oxygen a cikin ruwa.

Tasirin damuwa game da hypoxia a cikin tushen amfanin gona

Dalilan hypoxia na tushen

Akwai dalilai da dama da suka sa haɗarin hypoxia a cikin tsarin noman hydroponics da substrate ya fi yawa a lokacin rani. Da farko dai, cikakken iskar oxygen a cikin ruwa zai ragu yayin da zafin jiki ya tashi. Na biyu, iskar oxygen da ake buƙata don kula da ci gaban tushe yana ƙaruwa tare da ƙaruwar zafin jiki. Bugu da ƙari, yawan shan sinadarai yana ƙaruwa a lokacin rani, don haka buƙatar iskar oxygen don shan sinadarai ya fi girma. Yana haifar da raguwar yawan oxygen a cikin yanayin tushen da rashin ingantaccen ƙarin abinci, wanda ke haifar da hypoxia a cikin yanayin tushen.

Sha da girma

Shakar mafi yawan muhimman abubuwan gina jiki ya dogara ne akan hanyoyin da suka shafi metabolism na tushen, wanda ke buƙatar kuzarin da numfashin ƙwayoyin tushe ke samarwa, wato, rugujewar samfuran photosynthetic a gaban iskar oxygen. Bincike ya nuna cewa kashi 10% zuwa 20% na jimillar abubuwan da ke cikin shuke-shuken tumatir ana amfani da su a cikin tushen, kashi 50% ana amfani da su don sha ion na gina jiki, kashi 40% don girma da kashi 10% kawai don kulawa. Dole ne tushen ya sami iskar oxygen a cikin yanayin kai tsaye inda suke fitar da CO2.₂A ƙarƙashin yanayin rashin isasshen iska wanda ke haifar da rashin isasshen iska a cikin substrates da hydroponics, rashin isasshen iska zai shafi shan ruwa da abubuwan gina jiki. Rashin isasshen iska yana da saurin amsawa ga shan abubuwan gina jiki, wato nitrate (NO)₃^-), potassium (K) da phosphate (PO2)₄^3-), wanda zai kawo cikas ga shan sinadarin calcium (Ca) da magnesium (Mg) ba tare da aiki ba.

Girman tushen shuka yana buƙatar kuzari, aikin tushen da ya dace yana buƙatar mafi ƙarancin yawan iskar oxygen, kuma yawan iskar oxygen da ke ƙasa da ƙimar COP ya zama abin da ke iyakance metabolism na ƙwayoyin tushe (hypoxia). Lokacin da matakin iskar oxygen ya yi ƙasa, girman zai ragu ko ma ya tsaya. Idan hypoxia na tushen da ya ɗan yi kaɗan yana shafar rassan da ganye kawai, tsarin tushen zai iya rama ɓangaren tsarin tushen da ba ya aiki saboda wani dalili ta hanyar ƙara yawan shan ruwa a cikin gida.

Tsarin metabolism na shuka ya dogara ne akan iskar oxygen a matsayin mai karɓar electron. Idan babu iskar oxygen, samar da ATP zai tsaya. Idan babu ATP, fitar da protons daga tushen zai tsaya, ruwan tantanin halitta na ƙwayoyin tushe zai zama mai acidic, kuma waɗannan ƙwayoyin za su mutu cikin 'yan awanni. Rashin iskar oxygen na wucin gadi da na ɗan gajeren lokaci ba zai haifar da damuwa mai gina jiki ba a cikin tsire-tsire. Saboda tsarin "numfashi na nitrate", yana iya zama daidaitawa na ɗan gajeren lokaci don jure wa rashin iskar oxygen a matsayin wata hanya ta daban yayin rashin iskar oxygen na tushen. Duk da haka, rashin iskar oxygen na dogon lokaci zai haifar da raguwar girma, raguwar yankin ganye da raguwar nauyin sabo da bushewa, wanda zai haifar da raguwar yawan amfanin gona.

Ethylene

Tsire-tsire za su samar da ethylene a wurinsu a ƙarƙashin matsin lamba mai yawa. Yawanci, ana cire ethylene daga tushen ta hanyar yaɗuwa cikin iskar ƙasa. Lokacin da ruwa ya yi ambaliya, samuwar ethylene ba wai kawai zai ƙaru ba, har ma zai ragu sosai saboda tushen yana kewaye da ruwa. Ƙara yawan ethylene zai haifar da samuwar kyallen iska a cikin tushen (Hoto na 2). Ethylene kuma na iya haifar da tsufa ga ganye, kuma hulɗar da ke tsakanin ethylene da auxin zai ƙara samuwar tushen da ke tasowa.

Matsalar iskar oxygen tana haifar da raguwar girman ganye

Ana samar da ABA a cikin saiwoyi da ganye don magance matsalolin muhalli daban-daban. A cikin yanayin tushen, amsawar da aka saba bayarwa ga damuwa ita ce rufewar stomatal, wanda ya haɗa da samuwar ABA. Kafin a rufe stomata, saman shukar yana rasa matsin lamba na kumburi, ganyen sama suna bushewa, kuma ingancin photosynthesis shima yana iya raguwa. Nazari da yawa sun nuna cewa stomata yana amsawa ga karuwar yawan ABA a cikin apoplast ta hanyar rufewa, wato, jimlar abun ciki na ABA a cikin waɗanda ba ganye ba ta hanyar sakin ABA ta cikin ƙwayoyin halitta, tsire-tsire na iya ƙara yawan apoplast ABA da sauri. Lokacin da tsire-tsire ke ƙarƙashin matsin lamba na muhalli, suna fara sakin ABA a cikin ƙwayoyin halitta, kuma ana iya watsa siginar sakin tushen cikin mintuna maimakon awanni. Ƙarar ABA a cikin kyallen ganye na iya rage tsayin bangon tantanin halitta kuma yana haifar da raguwar tsayin ganye. Wani tasirin hypoxia shine tsawon rayuwar ganye yana raguwa, wanda zai shafi dukkan ganye. Hypoxia yawanci yana haifar da raguwar jigilar cytokinin da nitrate. Rashin sinadarin nitrogen ko cytokinin zai rage lokacin kula da yankin ganye kuma ya dakatar da girman rassan da ganye cikin 'yan kwanaki.

Inganta yanayin iskar oxygen na tsarin tushen amfanin gona

Halayen substrate suna da mahimmanci wajen rarraba ruwa da iskar oxygen. Yawan iskar oxygen a cikin yanayin tushen kayan lambu na greenhouse yana da alaƙa da ƙarfin riƙe ruwa na substrate, ban ruwa (girma da mita), tsarin substrate da zafin zaren substrate. Sai lokacin da iskar oxygen a cikin yanayin tushen ya kai aƙalla 10% (4 ~ 5mg/L) ne za a iya kiyaye aikin tushen a cikin mafi kyawun yanayi.

Tsarin tushen amfanin gona yana da matuƙar muhimmanci ga ci gaban shuka da juriya ga cututtukan shuka. Ruwa da abubuwan gina jiki za su sha daidai da buƙatun shuke-shuke. Duk da haka, matakin iskar oxygen a cikin yanayin tushen ya fi ƙayyade ingancin sha na abubuwan gina jiki da ruwa da kuma ingancin tsarin tushen. Isasshen matakin iskar oxygen a cikin yanayin tushen zai iya tabbatar da lafiyar tsarin tushen, don haka shuke-shuke za su sami juriya mafi kyau ga ƙwayoyin cuta masu cutarwa (Hoto na 3). Isasshen matakin iskar oxygen a cikin substrate kuma yana rage haɗarin yanayin rashin lafiyar, don haka rage haɗarin ƙwayoyin cuta masu cutarwa.

Amfani da iskar oxygen a cikin yanayin tushen

Matsakaicin yawan iskar oxygen da amfanin gona zai iya kaiwa har 40mg/m2/h (cin amfanin ya dogara da amfanin gona). Dangane da zafin jiki, ruwan ban ruwa na iya ɗauke da har zuwa 7 ~ 8mg/m2/h na iskar oxygen (Hoto na 4). Don isa 40 mg, dole ne a ba da lita 5 na ruwa kowace awa don biyan buƙatar iskar oxygen, amma a zahiri, adadin ban ruwa a cikin rana ɗaya ba za a iya isa ba. Wannan yana nufin cewa iskar oxygen da ban ruwa ke bayarwa ba ta taka rawa kaɗan ba. Yawancin iskar oxygen da ake samarwa yana kaiwa yankin tushen ta cikin ramuka a cikin matrix, kuma gudummawar da ake bayarwa ta hanyar iskar oxygen ta cikin ramuka tana da yawa har zuwa 90%, ya danganta da lokacin rana. Lokacin da ƙafewar tsirrai ya kai matsakaicin, adadin ban ruwa kuma ya kai matsakaicin, wanda yayi daidai da 1 ~ 1.5L/m2/h. Idan ruwan ban ruwa ya ƙunshi 7mg/L oxygen, zai samar da 7 ~ 11mg/m2/h oxygen ga yankin tushen. Wannan yayi daidai da 17% ~ 25% na buƙata. Hakika, wannan ya shafi yanayin da ruwan ban ruwa da ke cikin substrate ɗin da ba shi da isashshen iskar oxygen, ke maye gurbinsa da ruwan ban ruwa mai kyau.

Baya ga cin tushen, ƙananan halittu a cikin yanayin tushen suma suna shan iskar oxygen. Yana da wuya a auna wannan saboda ba a yi wani ma'auni ba a wannan fanni. Tunda ana maye gurbin sabbin abubuwa kowace shekara, ana iya ɗauka cewa ƙananan halittu ba sa taka rawa sosai wajen amfani da iskar oxygen.

Inganta yanayin zafi na muhalli na tushen

Zafin muhalli na tushen tushe yana da matuƙar muhimmanci ga girma da aikin tushen tushe, kuma yana da matuƙar muhimmanci wajen shafar shan ruwa da abubuwan gina jiki ta hanyar tushen.

Ƙananan zafin substrate (zafin tushen) na iya haifar da matsala wajen shan ruwa. A zafin 5℃, shan yana ƙasa da kashi 70% ~ 80% fiye da 20℃. Idan ƙarancin zafin substrate yana tare da babban zafin jiki, zai haifar da bushewar shuka. Sha ion a bayyane yake ya dogara da zafin jiki, wanda ke hana sha ion a ƙananan zafin jiki, kuma yadda abubuwan gina jiki daban-daban ke shafar zafin jiki ya bambanta.

Yawan zafin substrate shi ma ba shi da amfani, kuma yana iya haifar da babban tsarin tushen. A wata ma'anar, akwai rashin daidaiton rarraba busassun abu a cikin shuke-shuke. Saboda tsarin tushen ya yi yawa, asarar da ba dole ba za ta faru ta hanyar numfashi, kuma wannan ɓangaren makamashin da aka rasa za a iya amfani da shi don amfanin ɓangaren girbi na shuka. A yanayin zafi mafi girma, yawan iskar oxygen da aka narkar ya yi ƙasa, wanda ke da tasiri sosai ga yawan iskar oxygen a cikin yanayin tushen fiye da iskar oxygen da ƙwayoyin cuta ke cinyewa. Tsarin tushen yana cinye iskar oxygen mai yawa, har ma yana haifar da hypoxia idan aka sami rashin kyawun substrate ko tsarin ƙasa, don haka yana rage shan ruwa da ions.

Kiyaye ƙarfin riƙe ruwa mai dacewa na matrix.

Akwai rashin jituwa tsakanin yawan ruwa da kashi na iskar oxygen a cikin matrix. Lokacin da yawan ruwa ya ƙaru, yawan iskar oxygen yana raguwa, akasin haka. Akwai muhimmiyar tazara tsakanin yawan ruwa da iskar oxygen a cikin matrix, wato, kashi 80% ~ 85% na yawan ruwa (Hoto na 5). Kula da yawan ruwa sama da kashi 85% na dogon lokaci a cikin substrate zai shafi wadatar iskar oxygen. Yawancin wadatar iskar oxygen (75% ~ 90%) tana ta cikin ramuka a cikin matrix.

Ƙarin ban ruwa zuwa yawan iskar oxygen a cikin substrate

Hasken rana zai haifar da yawan shan iskar oxygen da ƙarancin yawan iskar oxygen a tushen sa (Hoto na 6), kuma yawan sukari zai sa yawan shan iskar oxygen ya ƙaru da dare. Zubar ruwa yana da ƙarfi, shan ruwa yana da yawa, kuma akwai ƙarin iska da ƙarin iskar oxygen a cikin substrate. Ana iya gani daga gefen hagu na Hoto na 7 cewa yawan iskar oxygen a cikin substrate zai ƙaru kaɗan bayan ban ruwa a ƙarƙashin yanayin cewa ƙarfin riƙe ruwa na substrate yana da yawa kuma yawan iskar yana da ƙasa sosai. Kamar yadda aka nuna a gefen dama na Hoto na 7, a ƙarƙashin yanayin haske mafi kyau, yawan iska a cikin substrate yana ƙaruwa saboda ƙarin shan ruwa (lokacin ban ruwa iri ɗaya). Tasirin ban ruwa akan yawan iskar oxygen a cikin substrate ya yi ƙasa da ƙarfin riƙe ruwa (abun da ke cikin iska) a cikin substrate.

Tattauna

A zahirin samarwa, ana iya yin watsi da iskar oxygen (iska) a cikin yanayin tushen amfanin gona cikin sauƙi, amma muhimmin abu ne don tabbatar da ci gaban amfanin gona yadda ya kamata da kuma ci gaban tushen lafiya.

Domin samun mafi girman yawan amfanin gona yayin samar da amfanin gona, yana da matukar muhimmanci a kare yanayin tushen tsarin a cikin mafi kyawun yanayi gwargwadon iko. Bincike ya nuna cewa O₂Abubuwan da ke cikin yanayin tushen ƙasa da 4mg/L za su yi mummunan tasiri ga ci gaban amfanin gona.₂Abubuwan da ke cikin tushen tushen galibi suna shafar ban ruwa (yawan ban ruwa da yawansa), tsarin substrate, yawan ruwan substrate, zafin greenhouse da substrate, da kuma nau'ikan shuka daban-daban za su bambanta. Algae da ƙananan halittu kuma suna da alaƙa da iskar oxygen a cikin yanayin tushen amfanin gona na hydroponic. Hypoxia ba wai kawai yana haifar da jinkirin ci gaban tsirrai ba, har ma yana ƙara matsin lamba na ƙwayoyin cuta na tushen (pythium, phytophthora, fusarium) akan ci gaban tushe.

Tsarin ban ruwa yana da tasiri mai mahimmanci akan O₂abun da ke cikin substrate, kuma hanya ce mafi kyau ta sarrafa shi a cikin tsarin shuka. Wasu nazarin shukar fure sun gano cewa a hankali ƙara yawan ruwa a cikin substrate (da safe) na iya samun yanayin iskar oxygen mafi kyau. A cikin substrate ɗin da ke da ƙarancin ƙarfin riƙe ruwa, substrate ɗin zai iya kiyaye yawan iskar oxygen, kuma a lokaci guda, ya zama dole a guji bambancin yawan ruwa tsakanin substrate ta hanyar yawan ban ruwa da gajeren tazara. Ƙananan ƙarfin riƙe ruwa na substrate, mafi girman bambanci tsakanin substrate. Danshi mai laushi, ƙarancin yawan ban ruwa da tsawon tazara yana tabbatar da ƙarin maye gurbin iska da yanayin iskar oxygen mai kyau.

Magudanar ruwa ta substrate wani abu ne da ke da babban tasiri ga saurin sabuntawa da kuma saurin yawan iskar oxygen a cikin substrate, ya danganta da nau'in da ƙarfin riƙe ruwa na substrate. Bai kamata ruwan ban ruwa ya daɗe a ƙasan substrate ba, amma ya kamata a fitar da shi da sauri don ruwan ban ruwa mai wadataccen iskar oxygen ya sake isa ƙasan substrate. Saurin magudanar ruwa na iya shafar wasu ma'auni masu sauƙi, kamar saurin magudanar ruwa a cikin kwatancen tsayi da faɗi. Girman magudanar ruwa, saurin magudanar ruwa. Substrate daban-daban suna da ramuka daban-daban kuma adadin wuraren fitar ruwa suma sun bambanta.

ƘARSHE

[bayanin ambato]

Xie Yuanpei. Tasirin iskar oxygen a cikin tushen amfanin gona na kore akan ci gaban amfanin gona [J]. Fasahar Injiniyan Noma, 2022,42(31):21-24.