BiotechHiranyagarbha · Class 11-12
Sookha-sahan ka genetics: ABA, stomata aur yield ka trade-off
Sookhe mein paudha apne stomata band kar leta hai. Toh scientists bas 'stomata band rakhne wala' gene daal kar fasal ko sookha-proof kyun nahi bana dete?
Socho pehle… phir dekho jawab
Kyunki wahi stomata CO2 bhi andar laate hain. Band stomata paani bachaate hain par photosynthesis aur upaj ghataate hain. Drought tolerance ek trade-off hai: survival vs yield.
Mechanism: paani ki kami mein paudha abscisic acid (ABA) banata hai, jise NCERT 'stress hormone' kehta hai. ABA stomata band karwata hai, jisse transpiration se paani ka nuksaan ghatata hai. Saath hi kai paudhe cells mein solutes jama karke (osmotic adjustment) paani pakde rehte hain, aur jadein gehri karte hain.
Trade-off: stomata band = CO2 kam = photosynthesis kam = upaj kam. Jo kism har halki kami par stomata band kar de, woh achhe saal mein kam anaaj de sakti hai. Breeding ka lakshya 'har keemat par survival' nahi, balki 'kam paani mein bhi theek upaj' hai.
Teen raaste: (1) conventional breeding aur marker-assisted selection (DNA markers se jaldi chunaav); (2) GM: NCERT Class 12 batata hai ki GM se faslein abiotic stress (thand, sookha, namak, garmi) ke prati zyada sahansheel banaayi ja sakti hain; (3) genome editing (jaise CRISPR) se paudhe ke apne gene mein chhota, sateek badlaav.
Debate dono taraf: samarthak kehte hain ki badalte mausam ke saath tez aur sateek tools chahiye; aalochak biosafety, beej par corporate niyantran aur genetic diversity ghatne ki chinta uthaate hain. Card ka sabak: Rayalaseema mein watershed, recharge aur kam paani wali faslein jaldi asar karti hain. Beej ek tool hai, poora jawab nahi.
Ghar pe try karo
Ek flowchart banao: paani ki kami → ABA → stomata band → (paani bacha) aur (CO2 kam → photosynthesis kam → upaj kam). Phir likho: tum breeder ho toh kaunsi kism chunoge, ek jo jaldi stomata band kare ya ek jo der se, aur kis ilaake ke liye? Ek line mein trade-off batao.
Wow!
Ek hi hormone, ABA, paudhe ko sookhe mein bachaata bhi hai aur beej ko sahi mausam tak 'sula' kar (dormancy) bhi rakhta hai!
3 sawaal
- Sookhe mein stomata band karwaane wala hormone kaunsa hai?
Jawab dekho
Abscisic acid (ABA). ABA stress hormone hai jo stomata band karwata hai.
- Stomata band rehne ka nuksaan kya hai?
Jawab dekho
CO2 kam, isliye photosynthesis aur upaj kam. Stomata se hi CO2 andar aati hai; band hone par photosynthesis ghatta hai.
- NCERT Class 12 ke anusaar GM faslon ka ek sambhavit fayda kya hai?
Jawab dekho
Abiotic stress (jaise sookha) ke prati zyada sahansheelta. NCERT GM faslon ko thand, sookha, namak aur garmi jaise abiotic stress ke prati zyada sahansheel banane ki baat karta hai.
NCERT se jodo: NCERT Class 11 Biology — plant growth regulators (ABA) aur transpiration; Class 12 Biology — biotechnology and its applications (GM crops)