Maize landraces from the mid and far western hills of Nepal: an evaluation for cultivar development

Of the total 145 landraces tested at Agricultural Research Station, Dailekh (Nepal) in summer 1999 and at The National Maize Research Program, Rampur, Chitwan, in winter 2000, twenty-seven landraces were selected on the basis of the yield performance and their phenotypic characters. The selected landraces were from Darchula, Baitadi, Bajhang, Dailekh, Salyan and Pyuthan districts (Nepal) of the mid and far wersern hills. These landraces were further evaluated in RCB design with the objectives of further studying the over all performance in the hill as well as in terai environments. Besides this, identifying and selecting the outstanding landraces for developing local germplasm based population suitable for the mid and far western hills was also the aim of this study. Four recommended composite varieties were used as checks. Field experiemnts were conducted at ARS, Dailekh in summer, 2002 and at Rampur in winter, 2001. The experimental result revealed highly significant differences in grain yield among the evaluated landraces in the hill environment. Similarly, highly significant differences in grain yield among the evaluated landraces in the hill environment. Similarly, highly significant differences were also found for yield when combined over locations. Non-significant differences in genotypes x environment interactions indicated that the landraces are stable and perform well across the environments. Pyuthan-1 produced the highest grain yield followed by Pyuthan-3, Darchula-18 and Pyuthan-12 respectively. These landraces are identified as outstanding landraces. However, two landraces from Salyan, five from Pyuthan and three from Darchula. In hill environment, grain yield ranged from 3620 kg per hectare in Baitadi-26 to 9909 kg per hectare in Pyuthan-1. Of the evaluated maize landraces, 15 landraces had produced at par yield with recommended checks viz, Manakamana-1, Rampur composite and Arun-2 respectively. Most of the landraces showed earlier in tasseling and silking in terai than in hill environment. In hill, 43 percent of the materials silked later than that of Rampur composite, which is considered as late among the checks. Landraces from Salyan, Pyuthan and Darchula took more days for silking as compared to the materials from Bajhang and Baitadi. This indicated that both early and medium maturing genotypes are of high demanding. ASI was not significant at both the locations. The average palnt height of the landraces in terai was 251 cm where as it was 265 when evaluated in the hill environment. Minimum plant height was recorded in Baitadi-28 where as the highest was observed in Pyuthan-3. Forty-eight percent of the landraces had ear placement in the middle of the plant where as the rest showed above the middle parts. Increased plant and ear height was recorded in most of the landraces when evaluated in the hill than those in terai environment. Reduction of the plant and ear height of these landraces is invetable for minimizing losses due to lodging. Reducing plant height of these landraces leads to make them more fertilizer responsive. Eighty-nine percent of the landraces showed medium maturity days but landraces from Baitadi were early maturing. Higher number of kernels/ear was observed in Darchula-22 followed by Darchula-12, Pyuthan-3 and Darchula-23 respectively. Of the total evaluated, 15 outstanding landraces have been selected on the basis of the agronomic performance, economic value, ecological adaptation and suitabuility of the socio-economic enviroument and locally adapted variability of these landraces. These outstanding landraces are being used for developing local germplasm based white population.