Evaluation of Cotton Germplasm for the Development of Multipurpose Variety

Abstract

A three years research project, Evaluation of cotton germplasm for the development of multipurpose variety, was initiated in the Department of Plant Breeding and genetics, University of Agriculture, Faisalabad during 1997. The project is funded by Pakistan Science Foundation, Islamabad. Main objective of the programme was to evaluate the available cotton germplasm in Pakistan for seed oil and protein content with the purpose to raise the breeding material for the development of cotton variety having higher oil and protein contents along with acceptable yield and fibre quality traits. During the period of project, 300 lines/varieties of cotton were collected from various cotton research stations/institutes of Punjab and Sindh, CRI and CRS Multan, CRS Bahawalpur, CRS Vehari, CRS Faisalabad PSC farms Khanewal, CRS Rahim Yar Khan, CRS Sahiwal, CRS D.I.Khan and cotton research institute Sakrand (CRIS) as well as some lines developed in the Department of Plant Breeding and Genetics, University of Agriculture, Faisalabad. Of the 300 lines, 250 lines, which were collected during first two years of the project, were planted in the field following a modified RCBD with three replications during May 1998. There were 10 blocks accommodating 25 accessions in each. The crop was harvested during December 1998. Similarly, another lot of 50 lines was collected during the 3rd year of the project, were planted in a similar layout during May 1999 and was harvested during December 1999. The data for various plant characters like, yield of seed cotton, ginning outrun, staple length and fibre fineness were recorded. Data for oil and protein content were recorded using the Soxhlet and kjeldahl techniques. Block wise, as well as pooled analysis of variance was performed, which revealed significant variation for all the characters except for gaining outturn percentage in Blocks 8and 11 non-significant variation was observed. The characters generally indicated non-significant correlation (positive or negative) among them except between yield and staple length and fibre fineness is undesirable though, as lower values (micronaire) indicate greater fibre fineness. Since, the main aim of the project was oil content without sacrificing other yield and quality characters, therefore, for selecting promising accessions a selection index was developed by giving weightage to oil contents. Based upon the selection index three high oil content accessions were selected from each of the 12 blocks. Thus, in total 36 accessions were recognise having high oil contents and an acceptable level of yield other characters.