BiotechPushan · Class 9-10
Abiotic stress aur fasal sudhaar: hybridisation se genetic modification tak
Sookha ek 'abiotic stress' hai, yaani bina jeevit kaaran wala dabaav. Fasal ko iske liye taiyaar kaise karein: khet badal kar, ya beej badal kar?
Socho pehle… phir dekho jawab
Dono! NCERT Class 9 batata hai ki crop variety improvement ke lakshya hain: zyada upaj, achhi quality, biotic (keede, rog) aur abiotic (sookha, khaarapan, garmi) stress se resistance, jaldi pakna aur wider adaptability. Beej badalne ke do bade tareeke: hybridisation aur genetic modification.
Hybridisation ke teen prakar: intervarietal (ek hi species ki do kismein), interspecific (ek genus ki do species) aur intergeneric (alag genera). Iske baad selection aur kai saal ke field trials.
Genetic modification: kisi khaas gene ko daal kar khaas khoobi laana. Fark: breeding mein poore genome ka mel hota hai aur chunaav dheere hota hai; GM mein ek chuna hua gene jaata hai, par uske liye kade biosafety niyam hote hain.
Drought escape vs tolerance: escape = chhoti avadhi wali kism jo sookha aane se pehle pak jaaye; tolerance = paani ki kami mein bhi jeevit rehna (gehri jadein, paani bachaana). Bajra-jowar jaise millets kudrati taur par kam paani mein ug jaate hain.
Card ka data: Andhra Pradesh mein June-August baarish 197.6 mm rahi, normal 424.3 mm ke muqable (53.4% kami), El Niño ke chalte. 688 mein se 388 mandal sookhagrast: 283 severe, 105 moderate. So what: kharif bigadne ke baad rabi bowaai se pehle sahi beej ka faisla kisan ke karz ko bhi prabhavit karta hai.
Ghar pe try karo
Ek table banao: 'drought escape' aur 'drought tolerance' — har ek ki paribhasha, ek udaharan khoobi aur kisan ke liye ek fayda. Phir khud kami ka % nikaalo: (424.3 − 197.6) ÷ 424.3 × 100. Kya jawab card ke 53.4% se milta hai?
Wow!
Ek nayi fasal kism ko khet tak pahunchne mein aksar kai saal ke trials lagte hain — biology mein shortcut nahi hota!
3 sawaal
- Sookha kis tarah ka stress hai?
Jawab dekho
Abiotic. Sookha bina jeevit kaaran wala, yaani abiotic stress hai.
- Do alag genera ke paudhon ka cross kya kehlata hai?
Jawab dekho
Intergeneric. Alag genera ke beech cross intergeneric hybridisation hai.
- Drought escape ka matlab kya hai?
Jawab dekho
Chhoti avadhi wali kism jo sookhe se pehle pak jaaye. Escape mein fasal sookha aane se pehle hi apna chakra poora kar leti hai.
NCERT se jodo: NCERT Class 9 Science — improvement in food resources (crop variety improvement, hybridisation, genetic modification)