A Developmentally Regulated Deletion Element with Long Terminal Repeats Has \u3cem\u3eCis\u3c/em\u3e-Acting Sequences in the Flanking DNA

Approximately 6000 specific DNA deletion events occur during development of the somatic macronucleus of the ciliate Tetrahymena. The eliminated Tlr1 element is 13 kb or more in length and has an 825 bp inverted repeat near the rearrangement junctions. A functional analysis of the cis-acting sequences required for Tlr1 rearrangement was performed. A construct consisting of the entire inverted repeat and several hundred base pairs of flanking DNA on each side was rearranged accurately in vivo and displayed junctional variability similar to the chromosomal Tlr1 rearrangement. Thus, 11 kb or more of internal element DNA is not required in cis for DNA rearrangement. A second construct with only 51 bp of Tetrahymena DNA flanking the right junction underwent aberrant rearrangement. Thus, a signal for determination of the Tlr1 junction is located in the flanking DNA, 51 bp or more from the right junction. Within the Tlr1 inverted repeat are 19 bp tandem repeats. A construct with the 19mer repeat region deleted from the right half of the inverted repeat utilized normal rearrangement junctions. Thus, despite its transposon-like structure, Tlr1 is similar to other DNA rearrangements in Tetrahymena in possessing cis-acting sequences outside the deleted DNA

Participatory cotton breeding for organic and low input farming in Central India

Up to 80% of world’s organic cotton is produced in India. However, involved producers are facing increased difficulties to find suitable cultivars. Few hybrids selected for high input farming and genetically-modified (GM) cotton, which is explicitly excluded in organic farming, are presently dominating the Indian seed market. In addition farmers have lost their traditional knowledge on seed production and hybrid seed needs to be purchased each season

Comparative economics of rural and periurban dairy farming in Kalaburagi district of Karnataka

Cost of milk production is an important economic indicator in assessing the farm household efficiency in milk production as well as basis for price fixation. The study was undertaken to analyse the cost and returns of milk production in rural and periurban dairy farms of Kalaburagi district of Karnataka. The per day maintenance cost in periurban dairy farms (` 150.64) was highest compared to rural dairy farms (` 91.29)for local cows, crossbred cows and buffaloes. Among total maintenance costs of periurban dairy farming, feed and fodder costs accounted major share (73.49%) followed by labour cost (15.53%) and total fixed cost (7.73%). The return per litre of milk was highest (` 8.91) for crossbred cows followed by buffalo (` 4.82) and local cows (` 0.14). The net return from crossbred cow was more than that of buffalo and local cows indicating higher profitability in rearing crossbred cow in the study area