Genotypic and environmental interaction in advanced lines of rice under salt-affected soils of Punjab

Sixteen genotypes developed through hybridization and mutation breeding techniques were evaluated during the year 2003-04 on nine locations covering most of the area of Punjab province including Faisalabad, Toba Tek Singh and Jhang. NIAB-IRRI-9, Jhona-379 salt tolerant genotypes and super Basmati, a salt sensitive variety were included as standard checks. The tested material [six genotypes] was generated by crossing fine varieties of rice viz. Basmati-370 and Basmati-385 with three coarse varieties of rice viz. NIAB-IRRI-9, Jhona-349 and NIAB-Rice-1. The mutants [seven mutants] were derived by gamma irradiation of rice varieties, Basmati-370 and Basmati-385. The nine sets of experiments were conducted in the naturally high saline sodic soils having EC range of 9.2-18.13 d/Sm pH=8.65-9.50, and SAR=20.7-37.15. The seed yield data collected at maturity and stability parameters were computed to know genotypic x environment interaction and varietals performance. The combined analysis of variance showed highly significant variance in case of varieties, locations and varieties x locations interaction. Varieties and varieties x Environment [Lin] also showed highly significant differences. It means that genotypes exhibited different behavior in different locations / environments which is due to their different genetic make up. The behavior may be cross over [in which significant change in ranking occurs from one environment to another] or cross over nature [in which case the ranking of genotype remains constant across environments and the interaction is significant because of change in the magnitude of response] depending upon the ranking order of genotypes performance under different environment. In our study, only super Basmati behavior was of almost non cross over nature, while others had cross over type of interaction. Based on overall mean seed performance, mutant NIAB-Rice-4 and DM-38/88 produced significantly the highest grain yield [5.6 t/ha] followed by mutant line NIAB-Rice-5 [5.4 t/ha] and NIAB-rice-2 [5.3 t/ha]. The lowest performing genotype was super Basmati [3.0 t/ha]. The coarse variety Jhona-349 produced [4.8 t/ha] grain yield. Mutant line DM-38/88 showed significant regression co-efficient differences from unity while mutant line NIAB-Rice-4 showed non significant difference of regression co-efficient from unity. Mutant line, NIAB-Rice-4 also showed non significant difference of standard deviation to regression co-efficient from zero. All the three parameters of stability i.e. overall mean seed yield, regression co-efficient and standard deviation to regression, provided clear evidence that mutant line NIAB-Rice-4 produced maximum stable yield compared to super Basmati

Evaluation of advanced rice germplasm under water stress environment

Thirteen genotypes of rice comprising of approved varieties and elite candidate lines were studied at three different water regimes by supplying 12, 8 and 4 numbers of irrigations at different intervals/ stages. The experiment was conducted at NIAB Farm Faisalabad, Pakistan on a clay loam soil applying normal doses of N and P fertilizers during 2002-2003 keeping varieties in the main plot while treatments in sub plot. The data for twelve morphological characters i.e. days to flower, days to mature, plant height, panicle length, number of productive tillers, number of primary and secondary branches, 1000 grain weight, sterile grains per spike, number of total grains per spike, fertility percentage, grain yield were recorded and subjected to analysis of variance and means were compared following DMR test. Effect of water stress on different morphological attributes in all treatments showed significant differences. Plant height, branches per plant, number of grains and grain yield reduced at less number of irrigations while sterility percentage was increased at less moisture conditions. Maximum grain yield [5349 Kg/ha] was achieved at T1 where 12 number of irrigations were applied at T2 [8 irrigations] and T3 [4 irrigations]. The yield reduction was observed from 30.32% to 42.53%, respectively as compared to T1 [12 irrigations]. Rice variety DM 64198 produced the highest seed yield [4766 Kg/ha] followed by DM-3-89 [4770 Kg/ha].This might be due to different genetic make up of the breeding lines and their behavior and interaction in water stress environment. Furthermore, high irrigation level made possible the appropriate water availability possible at proper time for performing different types of physiochemical processes of development that hindered at less number of irrigation or water stress environment. It may be concluded that for achieving maximum economic yield, at least 12 irrigations were essential otherwise the production will be reduced to a considerable extent

Genotype and environment interaction effect on yield of cotton under naturally salt stress condition

Thirteen genotypes of cotton developed through hybridization and mutation breeding techniques were evaluated during two consecutives years 2002-03-04 on eight locations covering most of the area of Punjab province including Faisalabad, Toba Tek Singh and Jhang. The eight sets of experiments were conducted in the naturally highly saline sodic soils, EC ranges from 7.8-36.1 d/Sm, pH=8.1-8.8, SAR=10.1-40.5, Saturation percentage 31.3-40.8 and texture Sandy Clay loam and Clay loam. The seed yield data was collected at maturity and stability parameters were computed to know genotypic environment interaction and varietals performance. The combined analysis of variance showed highly significant variance in case of varieties, locations and varieties x environment [Lin] also showed highly significant differences. It means that genotypes exhibited different behavior in different locations/environments which is due to their different genetic make up. The behavior may be cross over [in which significant change in ranking order occurs from one environment to another] or cross over nature [in which case the ranking of genotypes remains constant across environments and the interaction is significant because of change in the magnitude of response] depending upon the ranking order of genotypes performance under different environments. In our study only S-12 behavior was of almost non cross over nature, while others had cross over type of interaction. Based on over all seed yield cotton variety NIAB-999 and CIM-707 produced highest seed yield cotton [3.2 t/ha, 3.17t/ha]. The lowest seed yield cotton was noted in S-12 [1.86 t/ha]. All the three parameters of stability i.e. overall mean seed yield cotton, regression coefficient and standard deviation to regression provided clear evidence that variety NIAB-999 and CIM-707 produced maximum stable yield compared to S-12

Genotypic and environmental interaction in advanced lines of wheat under salt-affected soils environment of Punjab

Wheat cultivars of diverse origin including approved varieties of different provinces of Pakistan i.e. Punjab, NWFP and Sindh were tested against different salinity levels in laboratory as well as in naturally saline fields in different ecological zones. Initially, 16 genotypes were studied for germination test at 6 different salinity levels ranging from 0-25 dS/m [2, 5, 10, 15, 20, 25, EC= dS/m]. Then, out of 16 cultivars, 11 were studied for the relative growth rate at different levels of salinity and after their study in the laboratory, 9 genotypes were selected for testing in the naturally saline areas of Punjab province. Under germination percentage study, the varieties viz. Pasban-90, Sarsabz, Bakhtawar, 93032 and 933118 were less affected than other varieties. As regards the relative plant growth, varieties viz. Sarsabz, Bakhtawar, and Pasban-90 were tolerant to salinity at seedling stage while Inqlab was graded as sensitive to salt stress. Regarding field performance, significant differences were observed in the varieties grown under different saline environments and varieties x environment interaction. Varieties x environment [Lin] interaction was non significant while nonlinear interaction [pooled deviation] was significant. Based on overall yield performance, the Sarsabz variety produced the highest seed yield [4.37 T/ha] followed by Bakhtawar [4.24 T/ha] and Pasban-90 [3.93 T/ha]. Regression coefficient values showed non significant differences to unity while standard deviation to regression showed significant differences to zero. These results indicated that the genotypes viz. Sarsabaz, Bakhtawar and Pasban-90 are better tolerant to saline environment as compared to others. The two genotypes, Marvi and 25219 had low regression values and can fit under stress environment

Genotype and environmental interaction in cowpea [Vigna Unguiculata-L] for yield and disease resistance

Twenty-six cowpea cultivars were tested for yellow mosaic virus resistance at NIAB Faisalabad. NCPM-1, Elite, IT-84-552, No.44, P-518, S.A. Dandy, IT-97k-350-4, IT-93K-452, IT-97K-1042-8 and IT-97K-497-2 showed resistant reaction to yellow mosaic virus disease. As the study was aimed to select disease resistant and high yielding cultivars. Five cultivars viz. NCPM-1, Elite. S.A. Dandy, IT-97K-497-2 and IT-97K-1042-8 were chosen and evaluated at five different ecological zones during the year 2003. At each location, the experiment was laid out in a randomized complete block design keeping 7.2 m[2] plot size in three repeats. At maturity the seed yield was collected and subjected to analysis of variance following stability parameters, varieties, environment and varieties x environment showed significant differences. Significant and highest seed yield [880 kg/ha] was observed in NIAB cowpea mutant-1 followed by Elite [729 Kg/ha]. The highest yielding genotypes i.e. NIAB cowpea Mutant-1 and Elite showed non-significant differences of regression coefficient from one. Moreover these genotypes also exhibited non-significant difference of standard deviation to regression from zero. Based on three parameters i.e. high mean seed yield, regression coefficient and standard deviation to regression, these genotypes showed excellent and trustworthy stable performance over different environment. Hopefully these genotypes will definitely be helpful for increasing one local production of cowpea crop

Effect of salinity on chlorophyll concentration, leaf area, yield and yield components of rice genotypes grown under saline environment

Salt tolerance in eighteen advanced rice genotypes was studied under an artificially salinized [EC=8.5 dSm-1] soil conditions after 90 days of transplanting. The results showed that the yield per plant, chlorophyll concentrations, fertility percentage, and number of productive tillers, panicle length and number of primary braches per panicle of all the genotypes were reduced by salinity. However, genotypes viz. Jhona-349 x Basmati- 370, NR-1, DM-59418, DM-63275, DM-64198 and DM-38-88 showed better salinity tolerance than others