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Concerted efforts are on in the direction of amalgamating two
positive combinations of yield components present in DL1266 and
DL1280-1, and optimising selection criteria leading to maximization
of productivity. This advanced material in pipeline has passed
through preliminary yield trials and are under testing in replicated
multilocation trials.
The Agropyron elongatum derived leaf rust resistance
gene Lr24 is effective till today in the Indian
subcontinent. This leaf rust resistance gene is linked with stem rust
resistance gene Sr24 which is effective to an array of
virulent and prevalent races in the country. All the newly developed
genotypes in the study carry this combination of leaf and stem rust
resistance genes , introgressed through two released wheats Vaishali
and Vidisha, the carrier of linked genes Lr24 /Sr24. All these
genotypes were found highly resistant to leaf and stem rusts when
tested as seedlings in the glasshouse and as adult plants at hot
spots.
Conclusion
The strategy adopted to design a new plant type has resulted in
the development of wheat varieties having 15.2% more yield than
PBW343, HD2329 and UP2338, the most popular wheat varieties in the
wheat belt of the country. The new plant type possesses moderate
tillering, higher number of grains per spike, high grain weight
(above 45 g/1000 grains) and higher biomass with dark green thick
broad and erect leaves. It also has thick stem having a plant height
between 85 and 100 cm. The newly constituted lines have maturity
duration between 120 and 135 days. Some of the early maturing lines
like DL1266-1 and DL1266-6 also have more per day productivity than
the cheek varieties and fit well in areas planted late after the
harvest of rice. The yield levels of three lines may increase by
20-30% in improved production management so as to harness maximum
yield potential. The second generation material developed by
utilizing the above genotypes (DL1266 group) are more promising as
they combine all the three yield components viz. high number of
grains per spike, high grain weight and high number of tillers per
plant along with resistance to leaf, stem and also to stripe
rust.
Acknowledgments
Authors are highly thankful to Sh. C. Thomas, Editor (English),
IARI, New Delhi for editing the article.
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