Hiki ke hoʻohana ʻia ka haʻalulu pahū laiki ʻo Kosakonia oryziphila NP19 ma ke ʻano he mea hoʻoulu ulu mea kanu a me kahi pesticide biological e kāohi i ka pahū laiki o ka ʻano KDML105.

Hōʻike kēia haʻawina ʻo ka haʻi rhizosphere symbiotic *Kosakonia oryziphila* NP19 i hoʻokaʻawale ʻia mai nā aʻa laiki he biopesticide hoʻolaha ulu a me ka biopesticide no ka kaohi ʻana i ka pahū laiki i hoʻokumu ʻia e *Pyricularia oryzae*. Ua hana ʻia nā hoʻokolohua in vitro ma nā lau hou o nā mea kanu laiki jasmine o ke ʻano Khao Dawk Mali 105 (KDML105). Ua hōʻike nā hopena ua kāohi pono ʻo NP19 i ka ulu ʻana o nā conidia *Pyricularia oryzae*. Ua kāohi ʻia ka maʻi *Pyricularia oryzae* ma lalo o ʻekolu mau kūlana lapaʻau like ʻole: ʻo ka mua, ua hoʻopili ʻia ka laiki me NP19 a ua hoʻokomo ʻia me nā conidia *Pyricularia oryzae*; ʻo ka lua, ua hoʻopili ʻia kahi hui ʻana o NP19 a me *Pyricularia oryzae* conidia i nā lau;
ʻO ka bacteria rhizosphere *Kosakonia oryziphila* NP19¹⁴ua hoʻokaʻawale ʻia mai nā aʻa laiki (*Oryza sativa* L. cv. RD6). Loaʻa iā *Kosakonia oryziphila* NP19 nā waiwai hoʻoulu ulu mea kanu, me ka hoʻopaʻa ʻana o ka nitrogen, ka hana ʻana o ka waikawa indoleacetic (IAA), a me ka hoʻoheheʻe ʻana o ka phosphate. ʻO ka mea hoihoi, hana ʻo *Kosakonia oryziphila* NP19 i ka chitinase^14.Ua hoʻomaikaʻi ka hoʻopili ʻana o *Kosakonia oryziphila* NP19 i nā hua laiki KDML105 i ke ola ʻana o ka laiki ma hope o ka maʻi ʻana o ka pahū laiki. ʻO ka pahuhopu o kēia noiʻi, ʻo ia ka (i) wehewehe ʻana i ke ʻano pale o *Kosakonia oryziphila* NP19 e kūʻē i ka pahū laiki a (ii) noiʻi i ka hopena o *Kosakonia oryziphila* NP19 i ka kaohi ʻana i ka pahū laiki.

He kuleana koʻikoʻi ko nā meaʻai i ka ulu ʻana a me ka ulu ʻana o nā mea kanu, e lawelawe ana ma ke ʻano he mau mea e kāohi ai i nā maʻi microbial like ʻole. ʻO ka meaʻai mineral o ka mea kanu e hoʻoholo ai i kona kūpaʻa ʻana i nā maʻi, nā ʻano morphological a i ʻole nā ​​​​ʻiʻo, a me ka virulence, a i ʻole ka hiki ke ola i nā pathogens. Hiki i ka Phosphorus ke hoʻolohi i ka ulu ʻana a hōʻemi i ke koʻikoʻi o ka pahū laiki ma ka hoʻonui ʻana i ka synthesis o nā hui phenolic. Hoʻemi pinepine ka Potassium i ka hanana o nā maʻi laiki he nui, e like me ka pahū laiki, ka bacterial leaf spot, ka leaf sheath spot, ka pala kumu, a me ka leaf spot. Ua hōʻike ʻia kahi noiʻi na Perrenoud hiki i nā mea hoʻouluulu potassium kiʻekiʻe ke hōʻemi i ka hanana o nā maʻi fungal o ka laiki a hoʻonui i ka hua. Ua hōʻike ʻia nā noiʻi he nui e hiki i nā mea hoʻouluulu sulfur ke hoʻomaikaʻi i ke kūpaʻa o nā mea kanu i nā pathogens fungal.²⁷ʻO ka nui o ka magnesium (kahi ʻāpana o ka chlorophyll) hiki ke alakaʻi i ka pahū ʻana o ka laiki.²¹Hiki i ka zinc ke pepehi pololei i nā pathogens, a laila e hōʻemi ana i ke koʻikoʻi o ka maʻi.²²Ua hōʻike ʻia nā hoʻokolohua kahua ʻoiai ʻoi aku ka nui o ka phosphorus, potassium, sulfur, a me ka zinc ma ka lepo kula ma mua o ka hoʻokolohua ipuhao, ua laha mau ka pahū laiki ma o nā lau laiki. ʻAʻole paha e kūpono loa nā meaʻai o ka lepo i ka kaohi ʻana i ka pahū laiki, no ka mea, ʻaʻole kūpono ka haʻahaʻa a me ka mahana no ka hoʻouka kaua ʻana o nā pathogens ikaika.
Ma nā hoʻokolohua kahua, ua ʻike ʻia ʻo Stenotrophomonas maltophilia, P. dispersa, Xanthomonas sacchari, Burkholderia multivorans, Burkholderia diffusa, Burkholderia vietnamiensis a me C. gleum i nā lāʻau āpau. Ua hoʻokaʻawale ʻia ʻo Stenotrophomonas maltophilia mai ka rhizosphere o ka palaoa, ka ʻoka, ka kukama, ka kulina, a me ka ʻuala a ua hōʻike i ka biocontrol.^hanae kūʻē iā Colletotrichum nymphaeae.28 Eia kekahi, ua hōʻike ʻia ʻo P. dispersa he kūpono ia e kūʻē i ka ʻeleʻele^{pala o}ʻuala.29 Eia kekahi, ua hōʻike ka ʻano R1 o Xanthomonas sacchari i ka hana kūʻē i ka pahū laiki a me ka pala panicle i hoʻokumu ʻia e Burkholderia^glumae.30Hiki iā Burkholderia oryzae NP19 ke hoʻokumu i kahi pilina symbiotic me nā ʻiʻo laiki i ka wā o ka germination a lilo i fungus symbiotic endemic no kekahi mau ʻano laiki. ʻOiai hiki i nā bacteria lepo ʻē aʻe ke noho i ka laiki ma hope o ke kāpili ʻana, ʻo ka fungus blast NP19, i ka wā i noho ʻia ai, e hoʻohuli i nā kumu he nui i ke ʻano pale o ka laiki e kūʻē i kēia maʻi. ʻAʻole wale ʻo NP19 e kāohi i ka ulu ʻana o P. oryzae ma mua o 50% (e ʻike i ka Papa Hoʻohui S1 ma ka appendix pūnaewele), akā hoʻemi pū i ka helu o nā lesions blast ma nā lau a hoʻonui i ka hua o ka laiki i hoʻopili ʻia a i hoʻopili ʻia me NP19 (RBf, RFf-B, a me RBFf-B) i nā hoʻokolohua kahua (Kiʻi S3).
ʻO ka haʻiki Pyricularia oryzae, ka mea e hoʻoulu ai i ka pahū ʻana o nā mea kanu, he haʻiki hemittrophic ia e pono ai nā meaʻai mai ka mea kanu kikowaena i ka wā o ka maʻi. Hoʻopuka nā mea kanu i nā ʻano oxygen reactive (ROS) e kāohi i ka maʻi fungal; akā naʻe, hoʻohana ʻo Pyricularia oryzae i nā ʻano hana like ʻole e pale aku i ka ROS i hana ʻia e ka mea kikowaena.³¹Me he mea lā he kuleana ko nā peroxidases i ke kū'ē ʻana i nā pathogens, me ka hoʻopili ʻana o nā protein paia cell, ka mānoanoa o nā paia xylem, ka hana ʻana o ROS, a me ka neutralization o ka hydrogen peroxide.³²Hiki i nā enzymes antioxidant ke lawelawe ma ke ʻano he ʻōnaehana scavenging ROS kikoʻī. Ma o ko lākou mau waiwai antioxidant, kōkua ka superoxide dismutase (SOD) a me ka peroxidase (POD) i ka hoʻomaka ʻana i nā pane pale, me ka lawelawe ʻana o SOD ma ke ʻano he laina pale mua.³³I ka laiki, hoʻoulu ʻia ka hana peroxidase mea kanu ma hope o ka maʻi ʻana me nā pathogens mea kanu e like me *Pyricularia oryzae* a me *Xanthomonas oryzae pv. Oryzae*.³²Ma kēia haʻawina, ua hoʻonui ʻia ka hana peroxidase i ka laiki i hoʻoulu ʻia a/a i hoʻokomo ʻia me *Magnaporthe oryzae* NP19; akā naʻe, ʻaʻole i hoʻopilikia ʻo *Magnaporthe oryzae* i ka hana peroxidase. ʻO Superoxide dismutase (SOD), ma ke ʻano he H₂O₂ synthase, e hoʻoulu ai i ka hōʻemi ʻana o O₂⁻ i H₂O₂. He kuleana koʻikoʻi ko SOD i ke kūʻē ʻana o nā mea kanu i nā pilikia like ʻole ma ke kaulike ʻana i ka nui o H₂O₂ i loko o ka mea kanu, no laila e hoʻonui ai i ka hoʻomanawanui o nā mea kanu i nā pilikia like ʻole³⁴. Ma kēia haʻawina, ma ka hoʻokolohua ipuhao, 30 mau lā ma hope o ka hoʻokomo ʻana o *Magnaporthe oryzae* (30 DAT), ʻo nā hana SOD i nā hui RF a me RBF he 121.9% a me 104.5% kiʻekiʻe ma mua o nā mea i loko o ka hui R, kēlā me kēia, e hōʻike ana i kahi pane SOD i ka maʻi *Magnaporthe oryzae*. Ma nā hoʻokolohua ipuhao a me ke kula, ʻo nā hana SOD i loko o ka laiki i hoʻopili ʻia me *Magnaporthe oryzae* NP19 he 67.7% a me 28.8% kiʻekiʻe ma mua o nā mea i loko o ka laiki i hoʻopili ʻole ʻia he 30 mau lā ma hope o ka hoʻopili ʻana. Hoʻopilikia ʻia nā pane biochemical o nā mea kanu e ke kaiapuni, ke kumu o ke kaumaha, a me ke ʻano o nā mea kanu³⁵. Hoʻopilikia pololei ʻia nā hana enzyme antioxidant o nā mea kanu e nā mea kaiapuni, kahi e hoʻopilikia ai i nā hana enzyme antioxidant o nā mea kanu ma ka hoʻololi ʻana i ke kaiāulu microbial o nā mea kanu.
ʻO ka maʻi fungus pahū laiki (Kosakonia oryziphila NP19, helu komo NCBI PP861312) i hoʻohana ʻia ma kēia noiʻi he ʻano¹³i hoʻokaʻawale ʻia mai nā aʻa o ka laiki RD6 ma ka moku ʻo Nakhon Phanom, Thailand (16° 59′ 42.9″ N 104° 22′ 17.9″ E). Ua mahi ʻia kēia ʻano i loko o ka wai momona (NB) ma 30°C a me 150 rpm no 18 hola. No ka helu ʻana i ka nui o ka bacteria, ua ana ʻia ka absorbance o ka hoʻokuʻu bacteria ma 600 nm. Ua hoʻoponopono ʻia ka nui o ka hoʻokuʻu bacteria i^10⁶CFU/mL me ka wai deionized sterile (_dH₂O). Ua hoʻokomo ʻia ka haʻalulu laiki (Pyricularia oryzae) ma kahi kiko ma luna o ka agar dextrose potato (PDA) a hoʻomoʻa ʻia ma 25°C no 7 mau lā. Ua hoʻoili ʻia ka mycelium fungal i ka medium agar bran laiki (2% (w/v) bran laiki, 0.5% (w/v) sucrose, a me 2% (w/v) agar i hoʻoheheʻe ʻia i loko o ka wai deionized, pH 7) a hoʻomoʻa ʻia ma 25°C no 7 mau lā. Ua kau ʻia kahi lau sterilized o kahi cultivar laiki susceptible (KDML105) ma luna o ka mycelium e hoʻoulu i nā conidia a hoʻomoʻa ʻia ma 25°C no 5 mau lā ma lalo o ka hui pū ʻana o UV a me ke kukui keʻokeʻo. Ua hōʻiliʻili ʻia nā conidia ma ka holoi mālie ʻana i ka mycelium a me ka ʻili lau i hoʻopilikia ʻia me 10 ml o ka hopena sterilized 0.025% (v/v) Tween 20. Ua kānana ʻia ka hopena fungal ma o ʻewalu mau papa o ka cheesecloth e wehe i ka mycelium, agar, a me nā lau laiki. Ua hoʻoponopono ʻia ka nui o nā conidia i loko o ka hoʻokuʻu ʻia i 5 × 10⁵ conidia/ml no ka nānā hou aku.
Ua hoʻomākaukau ʻia nā moʻomeheu hou o nā pūnaewele Kosakonia oryziphila NP19 ma ka hoʻoulu ʻana i loko o ka medium NB ma 37 °C no 24 hola. Ma hope o ka centrifugation (3047 × g, 10 min), ua hōʻiliʻili ʻia ka pellet cell, holoi ʻia i ʻelua manawa me ka 10 mM phosphate-buffered saline (PBS, pH 7.2), a hoʻokuʻu hou ʻia i loko o ka buffer like. Ua ana ʻia ka optical density o ka cell suspension ma 600 nm, e loaʻa ana kahi waiwai o kahi 1.0 (like me 1.0 × 10⁷ CFU/μl i hoʻoholo ʻia e ka plating ma nā papa agar nutrient). Ua loaʻa nā Conidia o P. oryzae ma ke kau ʻana iā lākou i loko o ka hopena PBS a me ka helu ʻana iā lākou me ka hoʻohana ʻana i kahi hemocytometer. Nā hoʻokuʻu ʻana o *K. oryziphila* NP19 a me *P. No nā hoʻokolohua hoʻoheheʻe lau, ua hoʻomākaukau ʻia nā conidia K. oryziphila* ma luna o nā lau laiki hou ma nā ʻano he 1.0 × 10⁷ CFU/μL a me 5.0 × 10² conidia/μL, kēlā me kēia. Penei ke ʻano hoʻomākaukau laiki: ua ʻoki ʻia nā lau 5 cm ka lōʻihi mai nā mea kanu laiki a waiho ʻia i loko o nā kīʻaha Petri i hoʻouhi ʻia me ka pepa omo i hoʻomaʻū ʻia. Ua hoʻokumu ʻia ʻelima mau hui lapaʻau: (i) R: nā lau laiki me ka ʻole o ka hoʻopili ʻana o ka bacteria ma ke ʻano he kaohi, i hoʻohui ʻia me ka 0.025% (v/v) Tween 20 solution; (ii) RB + F: laiki i hoʻopili ʻia me K. oryziphila NP19, i hoʻohui ʻia me 2 μL o ka conidia hoʻokuʻu ʻia o ka fungus e hoʻoulu ai i ka pahū laiki; (iii) R + BF: Laiki ma ka hui R i hoʻohui ʻia me 4 μl o ka hui ʻana o ka hoʻokuʻu ʻia ʻana o ka conidia fungal blast a me K. oryziphila NP19 (lakio nui 1:1); (iv) R + F: ʻO ka laiki ma ka hui R i hoʻohui ʻia me 2 μl o ka hoʻokuʻu ʻana o ka conidia fungal blast; (v) RF + B: ʻO ka laiki ma ka hui R i hoʻohui ʻia me 2 μl o ka hoʻokuʻu ʻana o ka conidia fungal blast ua hoʻomoʻa ʻia no 30 hola, a laila ua hoʻohui ʻia he 2 μl o K. oryziphila NP19 ma kahi hoʻokahi. Ua hoʻomoʻa ʻia nā kīʻaha Petri āpau ma 25°C i ka pōʻeleʻele no 30 hola a laila ua kau ʻia ma lalo o ka mālamalama mau. Ua hoʻokumu ʻia kēlā me kēia hui ma ke ʻano he ʻekolu. Ma hope o 72 hola o ka moʻomeheu, ua nānā ʻia a kālailai ʻia nā ʻiʻo mea kanu e ka microscopy electron scanning (SEM). I ka pōkole, ua hoʻopaʻa ʻia nā ʻiʻo mea kanu i loko o ka buffer phosphate e loaʻa ana he 2.5% (v/v) glutaraldehyde a ua hoʻomaloʻo ʻia ma o kahi moʻo o nā hopena ethanol. Ma hope o ka hoʻomaloʻo ʻana i ke kiko koʻikoʻi me ke kalapona ʻokikene, ua uhi ʻia nā laʻana me ke gula a ua nānā hope ʻia me ka hoʻohana ʻana i kahi microscope electron scanning.¹⁵