REPORT - Search CIMMYT repository

Sonora 64. Like the aforementioned new variety,
it also is a three-gene dwarf. It has high
resistance to stripe and stem rust and adequate
resistance to leaf rust. It is resistant to mildew.
It will diversify the disease resistance now
available in commerc'ial varieties, and therein
lies its greatest value. It is best adapted to
the North-western Plains but is somewhat inferior
to Kalyansona yield in most areas. It
has larger grain. A third variety to 'be known
as Kiran was approved for release. Its parentage
is Frontana x Kenia 58-Newthatch x [(Norin
10-Brevor 21 x P 14) Kentana 54 B.] -This
variety was selected and tested under its introduction
number E 4870, by the Bhowali Station.
It has a very high degree of resistance
to all three species of rust. It is adapted to
the high elevation wheat culture of the Himalayas.
In the more advanced material, two new
durum varieties" known as HI 6-23 and A-2-30-1
are now in the 'final stages of testing. These
varieties are being developed at Indore M.P.
and Arnej in Gujarat and appear promising in
some of the dryland areas.
In the past two years a large number of
newer 3-gene dwarfs have been under test.
In 1968-69 three varieties with wide adaptation
were identified in a nationally grown test. These
three identified as HD 1941, HD 1944 and HD
1949, developed at the Indian Agricultural Research
Institute, yielded more than the principal
commercial variety Kalyansona. It was felt that
this could have been the result of their early
heading and somewhat earlier maturity since
early varieties were favored in the weather
conditions last year. On the basis of tests conducted
at four of the northern stations, however,
an average increase of 22.4, 18.6 and
17.7 percent respectively above Kalyansona
was obtained in all tests except at one location
where heavy yellow rust and mildew attacked
HD 1944 and HD 1949. HD 1941 has good rasistaflce
to stripe and stem rusts and to mildew.
It is moderately susceptible to leaf rust.
HD 1944 is resistant to stem rust but susceptible
to stripe rust, leaf rust and mildew. HD
1949 is resistant to stem rust and moderately
resistant to leaf rust. It is susceptible to stripe
rust and mildew. Aside from its weaknesses
in disease susceptibility HD 1949 is the most
widely adapted of the three. Parentages are
HD 1941 -(Yaktana 54 x Norin 1O-Brevor) x
Sonora 64; HD 1944 -(Yaktana 54 x Norin 10­
BrevOF) XNP 875, and HD 1949-(Yaktana 54 x
Norin 1O-Brevor) XNP 852. These or other lines
when approved for release will further diversify
the disease resistance and will provide additional
protection to the commercial crops.
Among the lines which are showing promise
at an earlier stage of testing, are several
from the CIMMYT-Mexican Bluebird cross
23584 [(Ciano "s") x (Sonora 64-Klein Rendidor)
x 8156]. Many other crosses and selections
aside from those specifically mentioned
have given promis'ing preliminary results.
Agronomic Research
One hundred and five agronomic trials were
sown this year. These included 71 under irrigation,
31 on dryland, one on weed control
and one on dwarf durums.
The folJowing trials were conducted under
irrigated culture:
1. Trials on date arid rate of seeding with
varieties were conducted at ten centers.
2. A rates of nitrogen test at fourteen.
3. A rates x time and method of nitrogen
application at eleven.
4. An optimum time of first irrigation at
nine.
5. One on critical stages of irrigation at
ten.
6. A rates of P 2 0 S application on ten cultivators'
fields.
7. A row spacing by seed rate trial with
three gene dwarfs at seven centers.
On "barani" (rainfed) culture the trials included:
1. Rates of N at ten centers.
2. Rates and methods of application of N
at eight.
3. Row-spacing x seed rate x varieties at
nine.
4. Late sown studies at four.
Two special studies, one' on weed control
at Powarkheda and one on rates of N on dwarf
durums at Rajendianagar, were conducted. Results
from these tests have not yet been compiled.
During the past year, based on favorable
findings in previous years, officers of the
IARll and ICAR2 with financial support from
USAID, supervised an aerial spray application
of 20 and 40 percent llrea mixed with fungicides
and insecticides over 2,000 hectares in south-
1 I.A.R.I. = Indian Agricultural Research Institute.
• I.C.A.R. = Indian Council of Agricultural Research.
86