Effect of Recurrent Selection on Drought Tolerance and Related Morpho-Physiological Traits in Bread Wheat.
Drought is one of the major abiotic stresses affecting wheat yield. A recurrent selection program was conducted to improve the drought tolerance and yield of bread wheat using drought tolerant advanced breeding lines from a drought tolerant x susceptible cross (HI 1500 x HUW 510). The parental lines were evaluated for yield, biomass and harvest index (HI) in addition to the drought adaptive traits like Canopy Temperature (CT), chlorophyll content and Normalized Difference Vegetative Index (NDVI). After three rounds of recurrent selection, the half sib progenies exhibited a marked reduction in CT, chlorophyll content and biomass; whereas improvement was noted for yield, HI and NDVI. Drought tolerance of the half-sib population appeared enhanced as indicated by drought indices and grain yield. Compared to base population, half-sibs showed better HI, grain filling and a significant (17.1%) increase in grain yield under water stress conditions. Cooler canopies and increased early vigour might have contributed to drought tolerance. A favourable combination of gibberellin sensitive and insensitive Rhtalleles was observed in the recombinant progenies. However, increased yield under water stress had a negative trade off in reduction of biomass. The study also identified potential lines with high yield and drought tolerance for subsequent varietal development for water limited areas.
Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, Delhi, India.
Ramya
R
P
Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, Delhi, India.
Gyanendra Pratap
GP
Singh
Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, Delhi, India.
Neelu
N
Jain
Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, Delhi, India.
Pradeep Kumar
PK
Singh
Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, Delhi, India.
Manoj Kumar
MK
Pandey
Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, Delhi, India.
Kavita
K
Sharma
Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, Delhi, India.
Arun
A
Kumar
Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, Delhi, India.
Harikrishna
Division of Genetics, ICAR-Indian Agricultural Research Institute, New Delhi, Delhi, India.
Kumble Vinod
KV
Prabhu
D000064:Acclimatization; D018533:Biomass; D002734:Chlorophyll / Q000032:analysis; D057231:Climate Change; D003433:Crosses, Genetic; D055864:Droughts; D002523:Edible Grain / Q000235:genetics / Q000254:growth & development / Q000502:physiology*; D010641:Phenotype; D000069600:Plant Breeding / Q000379:methods*; D014908:Triticum / Q000235:genetics / Q000254:growth & development / Q000502:physiology*
D002734:Chlorophyll